TY - ER - TY - JOUR TI - Apparent latent heat of evaporation from clothing AU - Nocker, W. AU - DenHartog, E.A. AU - Holmér, I. AU - Kuklane, K. AU - Meinander, H. AU - Havenith, G. AU - Richards, M.G. AU - Wang, X. AU - Bröde, P. AU - Candas, V. T2 - Textile Research Journal DA - 2012/// PY - 2012/// VL - 82 IS - 4 SP - 374–384 ER - TY - JOUR TI - Profiles of Liquid Drops at the Bottom of Cylindrical Fibers Standing on Flat Substrates AU - Du, J. M. AU - Michielsen, S. AU - Lee, H. J. T2 - Langmuir AB - Based on Carroll’s derivation that describes a symmetric liquid drop sitting on an infinite cylindrical fiber and the shape of the drop, we have extended the derivation to describe a drop located at the bottom of cylindrical fibers standing on flat substrates. According to our derivation, the shape of the drop forms a bell as predicted by Carroll but is cut off by the flat substrate. This theoretical prediction was verified experimentally using water, ethylene glycol, and Kaydol drops on glass, nylon and polypropylene cylindrical fibers, and on polytetrafluoroethylene (PTFE) and polyester (PET) flat substrates. We found that only four parameters are required to obtain agreement between the theoretical shape and the observed shape: the drop volume, the fiber radius, the liquid–fiber contact angle, and liquid–flat substrate contact angle. DA - 2012/// PY - 2012/// DO - 10.1021/la2036407 VL - 28 IS - 1 SP - 722-728 UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000298904900091&KeyUID=WOS:000298904900091 ER - TY - JOUR TI - An N-Heterocyclic Carbene/Lewis Acid Strategy for the Stereoselective Synthesis of Spirooxindole Lactones AU - Dugal-Tessier, Julien AU - O’Bryan, Elizabeth A AU - Schroeder, Thomas BH AU - Cohen, Daniel T AU - Scheidt, Karl A T2 - Angewandte Chemie International Edition AB - A cooperative catalysis approach for the enantioselective formal [3+2] addition of α,β-unsaturated aldehydes to isatins has been developed. Homoenolate annulations of β-aryl enals catalyzed by an N-heterocyclic carbene (NHC) require the addition of lithium chloride for high levels of enantioselectivity. This NHC-catalyzed annulation has been used for the total synthesis of maremycin B. DA - 2012/// PY - 2012/// DO - 10.1002/anie.201201643 VL - 51 IS - 20 SP - 4963-4967 KW - asymmetric synthesis KW - homoenolates KW - homogeneous catalysis KW - Lewis acids KW - total synthesis ER - TY - JOUR TI - Effects of a Hydroxyl Substituent on the Reactivity of the 2,4,6-Tridehydropyridinium Cation, an Aromatic σ,σ,σ-Triradical AU - Jankiewicz, Bartłomiej J. AU - Vinueza, Nelson R. AU - Reece, Jennifer N. AU - Lee, Young C. AU - Williams, Peggy AU - Nash, John J. AU - Kenttämaa, Hilkka I. T2 - Chemistry - A European Journal AB - Abstract The reactivity of 3‐hydroxy‐2,4,6‐tridehydropyridinium cation was found to be drastically different from the reactivity of 2,4,6‐tridehydropyridinium cation. While the latter triradical reacts with tetrahydrofuran, dimethyl disulfide and ally iodide via three consecutive atom or group abstractions, the former triradical exhibits this behavior only with tetrahydrofuran. Only a single atom or group abstraction was observed for the 3‐hydroxy‐2,4,6‐tridehydropyridinium cation upon interaction with dimethyl disulfide and allyl iodide. This change in reactivity is caused by the hydroxyl group that strengthens the interactions between the two radical sites adjacent to it, thus reducing their reactivity. This explanation is supported by the observation of similar behavior for related biradicals. DA - 2012/1/16/ PY - 2012/1/16/ DO - 10.1002/chem.201102641 VL - 18 IS - 3 SP - 969–974 SN - 0947-6539 UR - http://dx.doi.org/10.1002/chem.201102641 KW - FT-ICR KW - ion-molecule reactions KW - reactivity KW - substituent effects KW - triradicals ER - TY - RPRT TI - High surface area fiber and textiles made from the same AU - Pourdeyhimi, B. AU - Chappas, W. DA - 2012/3/6/ PY - 2012/3/6/ M1 - US8129019B2 M3 - Patent SN - US8129019B2 ER - TY - RPRT TI - Staple fiber durable nonwoven fabrics AU - Anantharamaiah, N. AU - Pourdeyhimi, B. DA - 2012/4/3/ PY - 2012/4/3/ M1 - US8148279B2 M3 - Patent SN - US8148279B2 ER - TY - RPRT TI - Non-woven textile microwave patch antennas and components AU - Deaett, MA AU - Weedon, WH, III AU - Pourdeyhimi, Behnam DA - 2012/5/8/ PY - 2012/5/8/ M1 - US8174449B2 M3 - Patent SN - US8174449B2 ER - TY - BOOK TI - Introduction to Nonwovens Technology AU - Batra, S.K. AU - Pourdeyhimi, B. DA - 2012/// PY - 2012/// PB - Destech Publishing SN - 9781605950372 ER - TY - CONF TI - Green Materials: Strength of Soy Protein Nanofiber Mats AU - Khansari, S. AU - Sinha-Ray, S. AU - Yarin, A. AU - Pourdeyhimi, B. T2 - National Science Foundation, Division of Civil, Mechanical and Manufacturing Innovation (NSF CMMI) Engineering Research and Innovation Conference C2 - 2012/// CY - Northeastern University, Boston, MA DA - 2012/// PY - 2012/7/9/ ER - TY - CONF TI - Use of Additives to Enhance Electrostatic Charge in Filters AU - Kilic, A. AU - Shim, E. AU - Pourdeyhimi, B. T2 - Filtrex C2 - 2012/10// CY - Cologne, Germany DA - 2012/10// PY - 2012/10// ER - TY - CONF TI - Stretch and Recovery, Stretch Nonwovens AU - Pourdeyhimi, B. T2 - TechTextil C2 - 2012/4// CY - Atlanta, Georgia DA - 2012/4// PY - 2012/4// ER - TY - CONF TI - Pulsatile Fluid Flow Increases RUNX2 Expression in Human Adipose Derived Stem Cells Cultured on Novel Three-Dimensional High Surface Area Poly(L-Lactic Acid) Scaffolds AU - Tuin, S.A. AU - Miller, S.M. AU - Ganesh, V. AU - Cunningham, D.J. AU - Pfeiler, W.T. AU - Bernacki, S.H. AU - Pourdeyhimi, B. AU - Loboa, E.G. T2 - 14th Annual North Carolina Tissue Engineering and Regenerative Medicine Society Conference C2 - 2012/9// C3 - Proceedings of the 14th Annual North Carolina Tissue Engineering and Regenerative Medicine Society Conference CY - Raleigh, NC DA - 2012/9// PY - 2012/9// ER - TY - CONF TI - Biomimetic Forces and Scaffolds to Control Human Stem Cell Fate AU - Loboa, E.G. AU - Bodle, J. AU - Charoenpanich, A. AU - Mathieu, P. AU - Mohiti-Asli, M. AU - Tuin, S.A. AU - Williams, J. T2 - 11th Annual Meeting of the New Jersey Symposium on Biomaterials Science C2 - 2012/10// C3 - Proceedings of the 11th Annual Meeting of the New Jersey Symposium on Biomaterials Science CY - New Brunswick, NJ DA - 2012/10// PY - 2012/10// ER - TY - CONF TI - Novel High Surface Area Poly(L-Lactic Acid) Winged Fiber Scaffolds Increase RUNX2 Expression of Human Adipose Derive Stem Cells Exposed to Shear Stress AU - Tuin, S.A. AU - Miller, S.M. AU - Ganesh, V. AU - Cunningham, D.J. AU - Pfeiler, W.T. AU - Bernacki, S.H. AU - Pourdeyhimi, B. AU - Loboa, E.G. T2 - Annual Joint Meeting of the Materials Research Society and the Materials Information Society C2 - 2012/11// C3 - Proceedings of the Annual Joint Meeting of the Materials Research Society and the Materials Information Society CY - Raleigh, NC DA - 2012/11// PY - 2012/11// ER - TY - CONF TI - Durable Nonwovens with Stretch and Recovery AU - Pourdeyhimi, B. T2 - Man Made Fiber Conference C2 - 2012/9// CY - Dornbirn, Austria DA - 2012/9// PY - 2012/9// ER - TY - CONF TI - Stretch and Recovery, Stretch Nonwovens AU - Pourdeyhimi, B. T2 - Man Made Fiber Conference C2 - 2012/9// CY - Dornbirn, Austria DA - 2012/9// PY - 2012/9// ER - TY - CONF TI - A New Generation of Micro-Nano Fiber Nonwovens AU - Pourdeyhimi, B. T2 - Nonwovens Research Academy C2 - 2012/4// CY - Gothenburg, Sweden DA - 2012/4// PY - 2012/4// ER - TY - RPRT TI - Mixed Fiber and Nonwoven Fabrics Made from the Same AU - Pourdeyhimi, Behnam DA - 2012/7/4/ PY - 2012/7/4/ M1 - 101939469 M3 - China Patent SN - 101939469 ER - TY - RPRT TI - High Strength Durable Micro and Nano-Fiber Fabrics Produced by Fibrillating Islands in the Sea Fibers AU - Pourdeyhimi, Behnam DA - 2012/10/10/ PY - 2012/10/10/ M1 - 101641469 M3 - China Patent SN - 101641469 ER - TY - RPRT TI - Mixed Fiber and Nonwoven Fabrics Made from the Same AU - Pourdeyhimi, Behnam DA - 2012/5/1/ PY - 2012/5/1/ M1 - 2179081 M3 - Germany Patent SN - 2179081 ER - TY - RPRT TI - Mixed Fiber and Nonwoven Fabrics Made from the Same AU - Pourdeyhimi, Behnam DA - 2012/12/12/ PY - 2012/12/12/ M1 - 10-1210973 M3 - Korea Patent SN - 10-1210973 ER - TY - RPRT TI - An Improved Composite Filter Media with High Surface Area Fibers AU - Pourdeyhimi, Behnam DA - 2012/12/30/ PY - 2012/12/30/ M1 - 101617072 M3 - China Patent SN - 101617072 ER - TY - JOUR TI - Synthesis of S-doped graphene by liquid precursor AU - Gao, Hui AU - Liu, Zheng AU - Song, Li AU - Guo, Wenhua AU - Gao, Wei AU - Ci, Lijie AU - Rao, Amrita AU - Quan, Weijin AU - Vajtai, Robert AU - Ajayan, Pulickel M T2 - Nanotechnology AB - Doping is a common and effective approach to tailor semiconductor properties. Here, we demonstrate the growth of large-area sulfur (S)-doped graphene sheets on copper substrate via the chemical vapor deposition technique by using liquid organics (hexane in the presence of S) as the precursor. We found that S could be doped into graphene's lattice and mainly formed linear nanodomains, which was proved by elemental analysis, high resolution transmission microscopy and Raman spectra. Measurements on S-doped graphene field-effect transistors (G-FETs) revealed that S-doped graphene exhibited lower conductivity and distinctive p-type semiconductor properties compared with those of pristine graphene. Our approach has produced a new member in the family of graphene based materials and is promising for producing graphene based devices for multiple applications. DA - 2012/6/19/ PY - 2012/6/19/ DO - 10.1088/0957-4484/23/27/275605 VL - 23 IS - 27 SP - 275605 J2 - Nanotechnology OP - SN - 0957-4484 1361-6528 UR - http://dx.doi.org/10.1088/0957-4484/23/27/275605 DB - Crossref ER - TY - JOUR TI - Paintable Battery AU - Singh, Neelam AU - Galande, Charudatta AU - Miranda, Andrea AU - Mathkar, Akshay AU - Gao, Wei AU - Reddy, Arava Leela Mohana AU - Vlad, Alexandru AU - Ajayan, Pulickel M. T2 - Scientific Reports AB - If the components of a battery, including electrodes, separator, electrolyte and the current collectors can be designed as paints and applied sequentially to build a complete battery, on any arbitrary surface, it would have significant impact on the design, implementation and integration of energy storage devices. Here, we establish a paradigm change in battery assembly by fabricating rechargeable Li-ion batteries solely by multi-step spray painting of its components on a variety of materials such as metals, glass, glazed ceramics and flexible polymer substrates. We also demonstrate the possibility of interconnected modular spray painted battery units to be coupled to energy conversion devices such as solar cells, with possibilities of building standalone energy capture-storage hybrid devices in different configurations. DA - 2012/6/28/ PY - 2012/6/28/ DO - 10.1038/srep00481 VL - 2 IS - 1 J2 - Sci Rep LA - en OP - SN - 2045-2322 UR - http://dx.doi.org/10.1038/srep00481 DB - Crossref ER - TY - JOUR TI - Nitrogen-Doped Graphene-Rich Catalysts Derived from Heteroatom Polymers for Oxygen Reduction in Nonaqueous Lithium–O2 Battery Cathodes AU - Wu, Gang AU - Mack, Nathan H. AU - Gao, Wei AU - Ma, Shuguo AU - Zhong, Ruiqin AU - Han, Jiantao AU - Baldwin, Jon K. AU - Zelenay, Piotr T2 - ACS Nano AB - In this work, we present a synthesis approach for nitrogen-doped graphene-sheet-like nanostructures via the graphitization of a heteroatom polymer, in particular, polyaniline, under the catalysis of a cobalt species using multiwalled carbon nanotubes (MWNTs) as a supporting template. The graphene-rich composite catalysts (Co-N-MWNTs) exhibit substantially improved activity for oxygen reduction in nonaqueous lithium-ion electrolyte as compared to those of currently used carbon blacks and Pt/carbon catalysts, evidenced by both rotating disk electrode and Li–O2 battery experiments. The synthesis–structure–activity correlations for the graphene nanostructures were explored by tuning their synthetic chemistry (support, nitrogen precursor, heating temperature, and transition metal type and content) to investigate how the resulting morphology and nitrogen-doping functionalities (e.g., pyridinic, pyrrolic, and quaternary) influence the catalyst activity. In particular, an optimal temperature for heat treatment during synthesis is critical to creating a high-surface-area catalyst with favorable nitrogen doping. The sole Co phase, Co9S8, was present in the catalyst but plays a negligible role in ORR. Nevertheless, the addition of Co species in the synthesis is indispensable for achieving high activity, due to its effects on the final catalyst morphology and structure, including surface area, nitrogen doping, and graphene formation. This new route for the preparation of a nitrogen-doped graphene nanocomposite with carbon nanotube offers synthetic control of morphology and nitrogen functionality and shows promise for applications in nonaqueous oxygen reduction electrocatalysis for Li–O2 battery cathodes. DA - 2012/10/10/ PY - 2012/10/10/ DO - 10.1021/nn303275d VL - 6 IS - 11 SP - 9764-9776 J2 - ACS Nano LA - en OP - SN - 1936-0851 1936-086X UR - http://dx.doi.org/10.1021/nn303275d DB - Crossref KW - graphene KW - nitrogen doping KW - heteroatom polymer KW - non-precious-metal catalysts KW - oxygen reduction KW - Li-O-2 battery ER - TY - JOUR TI - Artificially Stacked Atomic Layers: Toward New van der Waals Solids AU - Gao, Guanhui AU - Gao, Wei AU - Cannuccia, E. AU - Taha-Tijerina, Jaime AU - Balicas, Luis AU - Mathkar, Akshay AU - Narayanan, T. N. AU - Liu, Zhen AU - Gupta, Bipin K. AU - Peng, Juan AU - Yin, Yansheng AU - Rubio, Angel AU - Ajayan, Pulickel M. T2 - Nano Letters AB - Strong in-plane bonding and weak van der Waals interplanar interactions characterize a large number of layered materials, as epitomized by graphite. The advent of graphene (G), individual layers from graphite, and atomic layers isolated from a few other van der Waals bonded layered compounds has enabled the ability to pick, place, and stack atomic layers of arbitrary compositions and build unique layered materials, which would be otherwise impossible to synthesize via other known techniques. Here we demonstrate this concept for solids consisting of randomly stacked layers of graphene and hexagonal boron nitride (h-BN). Dispersions of exfoliated h-BN layers and graphene have been prepared by liquid phase exfoliation methods and mixed, in various concentrations, to create artificially stacked h-BN/G solids. These van der Waals stacked hybrid solid materials show interesting electrical, mechanical, and optical properties distinctly different from their starting parent layers. From extensive first principle calculations we identify (i) a novel approach to control the dipole at the h-BN/G interface by properly sandwiching or sliding layers of h-BN and graphene, and (ii) a way to inject carriers in graphene upon UV excitations of the Frenkell-like excitons of the h-BN layer(s). Our combined approach could be used to create artificial materials, made predominantly from inter planar van der Waals stacking of robust bond saturated atomic layers of different solids with vastly different properties. DA - 2012/7/2/ PY - 2012/7/2/ DO - 10.1021/nl301061b VL - 12 IS - 7 SP - 3518-3525 J2 - Nano Lett. LA - en OP - SN - 1530-6984 1530-6992 UR - http://dx.doi.org/10.1021/nl301061b DB - Crossref KW - van der Waal solids KW - hexagonal boron nitride (h-BN): graphene KW - exfoliation KW - artificial stacking: misfit layer KW - ab-initio KW - dipole KW - exciton ER - TY - JOUR TI - Graphene Quantum Dots Derived from Carbon Fibers AU - Peng, Juan AU - Gao, Wei AU - Gupta, Bipin Kumar AU - Liu, Zheng AU - Romero-Aburto, Rebeca AU - Ge, Liehui AU - Song, Li AU - Alemany, Lawrence B. AU - Zhan, Xiaobo AU - Gao, Guanhui AU - Vithayathil, Sajna Antony AU - Kaipparettu, Benny Abraham AU - Marti, Angel A. AU - Hayashi, Takuya AU - Zhu, Jun-Jie AU - Ajayan, Pulickel M. T2 - Nano Letters AB - Graphene quantum dots (GQDs), which are edge-bound nanometer-size graphene pieces, have fascinating optical and electronic properties. These have been synthesized either by nanolithography or from starting materials such as graphene oxide (GO) by the chemical breakdown of their extended planar structure, both of which are multistep tedious processes. Here, we report that during the acid treatment and chemical exfoliation of traditional pitch-based carbon fibers, that are both cheap and commercially available, the stacked graphitic submicrometer domains of the fibers are easily broken down, leading to the creation of GQDs with different size distribution in scalable amounts. The as-produced GQDs, in the size range of 1–4 nm, show two-dimensional morphology, most of which present zigzag edge structure, and are 1–3 atomic layers thick. The photoluminescence of the GQDs can be tailored through varying the size of the GQDs by changing process parameters. Due to the luminescence stability, nanosecond lifetime, biocompatibility, low toxicity, and high water solubility, these GQDs are demonstrated to be excellent probes for high contrast bioimaging and biosensing applications. DA - 2012/1/6/ PY - 2012/1/6/ DO - 10.1021/nl2038979 VL - 12 IS - 2 SP - 844-849 J2 - Nano Lett. LA - en OP - SN - 1530-6984 1530-6992 UR - http://dx.doi.org/10.1021/nl2038979 DB - Crossref KW - Graphene quantum dots KW - carbon fibers KW - zigzag edge KW - luminescence KW - imaging ER - TY - JOUR TI - A simple method to synthesize continuous large area nitrogen-doped graphene AU - Gao, Hui AU - Song, Li AU - Guo, Wenhua AU - Huang, Liang AU - Yang, Dezheng AU - Wang, Fangcong AU - Zuo, Yalu AU - Fan, Xiaolong AU - Liu, Zheng AU - Gao, Wei AU - Vajtai, Robert AU - Hackenberg, Ken AU - Ajayan, Pulickel M. T2 - Carbon AB - Large area nitrogen (N)-doped graphene films were grown on copper foil by chemical vapor deposition. The as-grown films consisted of a single atomic layer that was continuous across the copper surface steps and grain boundaries, and could be easily transferred to a variety of substrates. N-doping was confirmed by X-ray photoelectron spectroscopy, Raman spectroscopy, and elemental mapping. N atoms were suggested to mainly form a “pyrrolic” nitrogen structure, and the doping level of N reached up to 3.4 at.%. The N-doped graphene exhibited an n-type behavior, and nitrogen doping would open a band gap in the graphene. This study presents use of a new liquid precursor to obtain large area, continuous and mostly single atom layer N-doped graphene films. DA - 2012/10// PY - 2012/10// DO - 10.1016/j.carbon.2012.05.026 VL - 50 IS - 12 SP - 4476-4482 J2 - Carbon LA - en OP - SN - 0008-6223 UR - http://dx.doi.org/10.1016/j.carbon.2012.05.026 DB - Crossref ER - TY - JOUR TI - Studies on atmospheric pressure glow discharge of helium-oxygen plasma treatment on polyester/cotton blended fabric AU - Kale, K. AU - Palaskar, S. AU - Hauser, P.J. AU - El-Shafei, A. T2 - BTRA Scan DA - 2012/// PY - 2012/// VL - 42 IS - 1 SP - 1-11 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84864772668&partnerID=MN8TOARS ER - TY - JOUR TI - Cotton bleaching optimization using a butyrolactam-based cationic bleach activator AU - Xu, C. AU - Shamey, R. AU - Hinks, D. AU - El-Shafei, A. T2 - AATCC Review DA - 2012/// PY - 2012/// VL - 12 IS - 1 SP - 66-70 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84855978049&partnerID=MN8TOARS ER - TY - JOUR TI - The effect of hue on the perception of blackness using munsell samples AU - Haslup, J.R.C. AU - Shamey, Renzo AU - Hinks, D. T2 - Color Research and Application AB - Although black is an important color, the perception of black objects has not been systematically examined. The purpose of this work was to determine the influence of hue on the perception of preferred blackness. A set of 20 glossy low chroma Munsell sheets were purchased comprising a complete hue circle with a value and chroma of two and one, respectively (L* = 19.3–20.75, and C* = 3.66–6.58). The Munsell samples were divided into two interleaved groups: (5R, 5YR, 5Y, 5GY, 5G, 5BG, 5B, 5PB, 5P, and 5RP) and (10R, 10YR, 10Y, 10GY, 10G, 10BG, 10B, 10PB, 10P, and 10RP). Fifty color‐normal observers force‐ranked the two sets of 10 samples from “most like black” to “least like black.” Observers then assessed a set of six samples that represented the three samples from each set of 10 that the observer chose to be “most like black.” The 50 observers were found to have fairly good autoconcordance and concordance values. In repeat experiments observers agreed with themselves in 81% of the pairwise decisions, and they agreed with the grand mean rank 76% of the time. The blue–green samples (with Munsell hue notations 10G, 5BG, and 10BG) were most selected (and were considered blackest), followed by green, blue, and purple–blue. The samples selected the fewest times by any observer as being most black were the red samples. The grand mean rankings demonstrate that greenish to bluish blacks are perceived by the observers as “blacker” than yellowish and reddish blacks. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 423–428, 2013 DA - 2012/// PY - 2012/// DO - 10.1002/col.21744 VL - 38 IS - 6 SP - 423–428 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84860215230&partnerID=MN8TOARS KW - blackness KW - blackness preference KW - psychophysical assessment of blackness KW - blackness in Munsell system ER - TY - JOUR TI - How do major color-difference formulae perform in the high chroma blue region? AU - Shamey, R. AU - Cao, R. AU - Zaidy, S.S.H. AU - Lin, J. AU - Lee, S.G. T2 - Final Program and Proceedings - IS and T/SID Color Imaging Conference DA - 2012/// PY - 2012/// SP - 242-247 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84876734604&partnerID=MN8TOARS ER - TY - JOUR TI - Evaluation of performance of several color-difference formulae using a new NCSU black experimental dataset AU - Shamey, R. AU - Lin, J. AU - Sawatwarakul, W. AU - Fang, G. T2 - Final Program and Proceedings - IS and T/SID Color Imaging Conference DA - 2012/// PY - 2012/// SP - 185-190 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84876744156&partnerID=MN8TOARS ER - TY - JOUR TI - A novel carbazole-based dye outperformed the benchmark dye N719 for high efficiency dye-sensitized solar cells (DSSCs) AU - El-Shafei, Ahmed AU - Hussain, Maqbool AU - Atiq, Aasim AU - Islam, Ashraful AU - Han, Liyuan T2 - Journal of Materials Chemistry AB - Two novel high molar extinction coefficient heteroleptic Ru(II) isomers, NCSU-10 and NCSU-10′, based on carbazole antenna were synthesized with the aid of Knoevenagel reaction, to study the influence of the carbazole antenna and anchoring group (COOH) isomerization on the light harvesting efficiency (LHE), ground and excited state oxidation potentials, incident-photon-to-current conversion efficiency (IPCE), short-circuit photocurrent density (JSC), and total solar-to-electric conversion efficiency (η) for DSSCs, and their device performances were compared to the benchmark dye N719. The photophysical and photoelectrochemical properties discussed herein addressed the significant impact of the carbazole antenna and the position of the anchoring group on JSC and η in DSSCs. Tetrabutylammonium (TBA) substituted NCSU-10 achieved efficient sensitization of nanocrystalline TiO2 over the whole visible range, extending into the near IR region (ca. 870 nm) with an excellent power conversion efficiency (η) of 9.37% under an irradiation of full sunlight (100 mW cm−2) with mask compared to 8.17% of N719 under optimized conditions. NCSU-10 outperformed N719 by 45% in molar absorptivity, 18.8% in JSC, and 14.6% in the total conversion efficiency. Molecular modeling studies (DFT/TD-DFT) of NCSU-10 and NCSU-10′ showed that the HOMO is delocalized not only on Ru and NCS but also on the carbazole with a large coefficient, indicating that the second charge generation transfer in the visible region at ∼400 nm is a mixture of metal-to-ligand charge transfer (MLCT) and strong ligand–ligand charge transfer (LLCT) with a significant HOMO coefficient originating from the carbazole antenna (π) to the bipyridyl electron acceptor (π*). Moreover, DFT calculations showed that the 4,4′-isomer (NCSU-10) is a significantly stronger electron acceptor than the 5,5′-isomer (NCSU-10′), which explained the inferior electron injection and significantly lower JSC of the 5,5′-isomer. DA - 2012/// PY - 2012/// DO - 10.1039/c2jm35267b VL - 22 IS - 45 SP - 24048 J2 - J. Mater. Chem. LA - en OP - SN - 0959-9428 1364-5501 UR - http://dx.doi.org/10.1039/c2jm35267b DB - Crossref ER - TY - JOUR TI - Functional Military Textile: Plasma-Induced Graft Polymerization of DADMAC for Antimicrobial Treatment on Nylon-Cotton Blend Fabric AU - Malshe, Priya AU - Mazloumpour, Maryam AU - El-Shafei, Ahmed AU - Hauser, Peter T2 - Plasma Chemistry and Plasma Processing DA - 2012/5/8/ PY - 2012/5/8/ DO - 10.1007/S11090-012-9380-1 VL - 32 IS - 4 SP - 833-843 J2 - Plasma Chem Plasma Process LA - en OP - SN - 0272-4324 1572-8986 UR - http://dx.doi.org/10.1007/S11090-012-9380-1 DB - Crossref KW - Antimicrobial KW - Plasma KW - DADMAC KW - Crosslinkers ER - TY - JOUR TI - Surface nanostructuring of kevlar fibers by atmospheric pressure plasma-induced graft polymerization for multifunctional protective clothing AU - Widodo, Mohamad AU - El-Shafei, Ahmed AU - Hauser, Peter J. T2 - Journal of Polymer Science Part B: Polymer Physics AB - Abstract Atmospheric plasma‐induced graft polymerization was employed successfully to generate free radical on the surface of Kevlar® (poly‐( p ‐phenylene terephthalamide or PPTA), and to initiate and control graft polymerization of cationic antimicrobial precursors diallyldimethylammonium chloride (DADMAC) or 3‐(trimethoxysilyl)propyl‐dimethyloctadecyl ammonium chloride (TMS) onto the fabric surface, which eliminates the need for separate processes that may involve thermal energy or UV irradiation. It was demonstrated that when the radiofrequency of the plasma power was 400 W, the radical density generated on the surface was 10 15 to 10 16 radicals cm −2 , which were enough to generate a poly‐DADMAC or poly‐TMS with surface charge of at least 2 × 10 17 N + /cm 2 , which is the minimum threshold for an effective cationic biocidal surface. In both cases, the grafted polymers were characterized and confirmed using SEM, FTIR, and XPS. The antimicrobial activity was measured using the AATCC Test Method 100, which showed that at least 3‐log reduction of bacteria colonies was achieved in the case of grafted poly‐DADMAC or grafted poly‐TMS on Kevlar®. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 DA - 2012/5/21/ PY - 2012/5/21/ DO - 10.1002/polb.23098 VL - 50 IS - 16 SP - 1165-1172 J2 - J. Polym. Sci. B Polym. Phys. LA - en OP - SN - 0887-6266 UR - http://dx.doi.org/10.1002/polb.23098 DB - Crossref KW - antimicrobial KW - atmospheric pressure plasma KW - diallyldimethylammonium chloride KW - Kevlar (R) KW - plasma-induced graft polymerization ER - TY - JOUR TI - Macromol. Rapid Commun. 1/2012 AU - Vargantwar, Pruthesh H. AU - Roskov, Kristen E. AU - Ghosh, Tushar K. AU - Spontak, Richard J. T2 - Macromolecular Rapid Communications AB - Back Cover: Ionic polymer-metal composites which bend in response to electric potential are fabricated using selectively-solvated block ionomers possessing a sulfonated midblock and hydrophobic endblocks. The electroactuation performance is comparable or superior to existing systems. Further details can be found in the article by P. H. Vargantwar, K. E. Roskov, T. K. Ghosh, and R. J. Spontak* on page 61. DA - 2012/1/3/ PY - 2012/1/3/ DO - 10.1002/marc.201290003 VL - 33 IS - 1 SP - 100-100 J2 - Macromol. Rapid Commun. LA - en OP - SN - 1022-1336 UR - http://dx.doi.org/10.1002/marc.201290003 DB - Crossref ER - TY - JOUR TI - Effect of acid value on the esterification mechanism of maleinized soybean oil with cotton AU - Ford, Ericka N. J. AU - Rawlins, James W. AU - Mendon, Sharathkumar K. AU - Thames, Shelby F. T2 - Journal of Coatings Technology and Research DA - 2012/5/30/ PY - 2012/5/30/ DO - 10.1007/S11998-012-9420-Z VL - 9 IS - 5 SP - 637-641 J2 - J Coat Technol Res LA - en OP - SN - 1547-0091 1935-3804 UR - http://dx.doi.org/10.1007/S11998-012-9420-Z DB - Crossref KW - Anhydride group KW - Amide group KW - Cellulose KW - Cotton KW - Infrared spectroscopy KW - Soybean oil ER - TY - JOUR TI - Influence of SWNTs on the Preferential Alignment of Molecular Moieties in PVA Fibers AU - Ford, Ericka Nicole Johnson AU - Minusa, Marilyn Lillith AU - Liu, Tao AU - Choi, Ji Il AU - Jang, Seung Soon AU - Kumar, Satish T2 - Macromolecular Chemistry and Physics AB - Abstract The alignment of electron‐donating moieties in SWNT‐embedded PVA fibers is characterized using infrared dichroism and polarized Raman spectroscopy. The SWNT alignment is found to influence the preferential alignment of PVA functional groups and solvent molecules with respect to the fiber axis. Furthermore, the fraction of oriented functional moieties depends more on the SWNT alignment than on the PVA chain orientation. Charge transfer between functional moieties and SWNTs results in molecular adhesion between the SWNTs and interacting groups, as confirmed by DFT calculations. DA - 2012/2/23/ PY - 2012/2/23/ DO - 10.1002/macp.201100534 VL - 213 IS - 6 SP - 617-626 J2 - Macromol. Chem. Phys. LA - en OP - SN - 1022-1352 UR - http://dx.doi.org/10.1002/macp.201100534 DB - Crossref KW - alignment KW - charge transfer KW - drawing KW - infrared spectroscopy KW - single-walled carbon nanotubes (SWNTs) ER - TY - JOUR TI - Ultrastrong, Stiff and Multifunctional Carbon Nanotube Composites AU - Wang, X. AU - Yong, Z.Z. AU - Li, Q.W. AU - Bradford, P.D. AU - Liu, W. AU - Tucker, D.S. AU - Cai, W. AU - Wang, H. AU - Yuan, F.G. AU - Zhu, Y.T. T2 - Materials Research Letters AB - Carbon nanotubes (CNTs) are an order of magnitude stronger than any other current engineering fiber. However, for the past two decades, it has been a challenge to utilize their reinforcement potential in composites. Here, we report CNT composites with unprecedented multifunctionalities, including record high strength (3.8 GPa), high Young's modulus (293 GPa), electrical conductivity (1230 S·cm −1), and thermal conductivity (41 W m −1 K −1). These superior properties are derived from the long length, high volume fraction, good alignment and reduced waviness of the CNTs, which were produced by a novel-processing approach that can be easily scaled up for industrial production. DA - 2012/10/11/ PY - 2012/10/11/ DO - 10.1080/21663831.2012.686586 VL - 1 IS - 1 SP - 19-25 J2 - Materials Research Letters LA - en OP - SN - 2166-3831 UR - http://dx.doi.org/10.1080/21663831.2012.686586 DB - Crossref KW - Carbon Nanotubes KW - Composite Materials KW - Tensile Strength KW - Multifunctional KW - Alignment ER - TY - JOUR TI - Effect of accelerated point distribution on sliver irregularity. Part Ι: characterization of accelerated point distribution AU - Lin, Qian AU - Oxenham, William AU - Yu, Chongwen T2 - Journal of the Textile Institute AB - Abstract This paper introduces a new approach to characterize the accelerated point distribution in roller drafting. The approach uses 2-parameter Weibull distribution and Log-normal distribution to estimate the probability density function of the fiber accelerated point by including the influence of draft ratio and ratch, as well as fiber lengths. The coefficient of variation (CV) of accelerated points is then derived by employing conditional probability. The model was applied to a group of simulated data from literature and newly obtained experimental data of accelerated point distribution. The CV of the fiber accelerated points was compared with the CV from other published accelerated point distributions and the data derived from measurements of sliver irregularity. The model based on Log-normal distribution was proved to adequately characterize the probability density function of the fiber accelerated point. The accelerated point distribution would be a plausible variable to be utilized in the optimization of the draft settings. Keywords: roller draftaccelerated point distributionWeibull distributionLog-normal distributionconditional probabilitysliver irregularity Acknowledgements We’d like to thank Timothy Pleasants, Dzung Nguyen, and Teresa White from College of Textiles in North Carolina State University for supplying the materials and for assisting with our experiments. This research is supported by Shu Guang project of Shanghai Municipal Education Commission and Shanghai Education Development Foundation (Grant No. 10GG17). DA - 2012/5// PY - 2012/5// DO - 10.1080/00405000.2011.590008 VL - 103 IS - 5 SP - 549-557 J2 - Journal of The Textile Institute LA - en OP - SN - 0040-5000 1754-2340 UR - http://dx.doi.org/10.1080/00405000.2011.590008 DB - Crossref KW - roller draft KW - accelerated point distribution KW - Weibull distribution KW - Log-normal distribution KW - conditional probability KW - sliver irregularity ER - TY - JOUR TI - Review of Cost Estimation Techniques and Their Strategic Importance in the New Product Development Process of Textile Products AU - Ievtushenko, O. AU - Hodge, G.L. T2 - Research Journal of Textile and Apparel AB - Today, the strategy of innovation is perhaps the most pervasive strategy for textile companies to achieve a competitive advantage while facing severe competition in the global textile market. To be successful a company must bring new products to the market which can completely satisfy customers' expectations, as well as the company's desire to increase its profitability. Because product price is an important decisive factor which influences customers' purchase behavior, and it is generally established independently as a result of pure competition, the only way to get a higher profit margin is to reduce product costs. The product costs are committed as the product goes through new product development stages and it is therefore critical for the company to manage costs in every phase of this process. The main focus of this paper is to review current cost techniques and methods which can be successfully applied during the development of new textile products. This work builds a foundation for future research in the field of cost engineering of textile products and can be used by company's executives to become familiar with current cost estimating tools. DA - 2012/// PY - 2012/// DO - 10.1108/RJTA-16-01-2012-B012 VL - 16 IS - 1 SP - 103-124 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84912128794&partnerID=MN8TOARS ER - TY - JOUR TI - Postponement and supply chain structure: Cases from the textile and apparel industry AU - Chaudhry, H. AU - Hodge, G. T2 - Journal of Fashion Marketing and Management AB - Purpose The purpose of this paper is to explore the applications of postponement strategy in the textile and apparel industry, with a particular focus on the supply chain structure, relationships and enabling activities supporting postponement strategy across the supply chain. Design/methodology/approach For this research, a case study approach, supported by structured interviews, was adopted. The purpose was to explore the application of postponement with the objective of gathering considerable data from an organization or multiple organizations to develop the clearest possible picture of the phenomenon. Findings The nature of product, downstream demand and the supply chain structure impacts the choice of postponement strategy. Companies operating with manufacturing and logistics postponement share data across their supply chain extensively, while companies adopting purchasing postponement work towards enhancing suppliers’ capabilities and fostering relationships across their supply chains. Research limitations/implications The case study method limitations include lack of rigor and statistical generalization, small sample size and convenience sampling and lack of establishment of causal relationship. However a thorough study design and process can make case‐based research more rigorous and reliable, but caution still needs to be exercised while applying findings on differing scenarios. Originality/value The case studies depict the application of postponement and the enabling supply chain structures. Previous studies have either looked on the organizational perspective or supply chain perspective with regards to the power and dependence attributes. These cases look at the interaction routines and structures among the supply chains. DA - 2012/// PY - 2012/// DO - 10.1108/13612021211203032 VL - 16 IS - 1 SP - 64-80 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84857558548&partnerID=MN8TOARS KW - United States of America KW - Supply chain management KW - Buyer-seller relationships KW - Partnership KW - Textile industry KW - Garment industry KW - Textile/clothing supply chains ER - TY - JOUR TI - Evaluation of the Food Day School Curriculum to Teach Children Why and How to EAT REAL AU - Porter, K. AU - Koch, P. AU - Kotek, R. AU - Hays, M. AU - Contento, I. T2 - Journal of Nutrition Education and Behavior AB - To access how the Food Day School Curriculum (FDSC) affected students’ understandings and behaviors. DA - 2012/7// PY - 2012/7// DO - 10.1016/j.jneb.2012.03.166 VL - 44 IS - 4 SP - S71 J2 - Journal of Nutrition Education and Behavior LA - en OP - SN - 1499-4046 UR - http://dx.doi.org/10.1016/j.jneb.2012.03.166 DB - Crossref ER - TY - JOUR TI - Vortex spinning technology AU - Erdumlu, Nazan AU - Ozipek, Bulent AU - Oxenham, William T2 - Textile Progress AB - The latest development in air jet spinning technology is the Murata Vortex Spinner (MVS), which was firstly introduced at Osaka International Textile Machinery Show OTEMAS '97 by Murata Machinery Ltd. targeting the regular wear and casual fashion markets. Besides the main characteristics of modern spinning technologies, such as elimination of processing stages and ease of automation, distinctive features of the system are claimed to be the capability of spinning 100% carded cotton yarn and obtaining ring-like yarn structure at extremely high production speeds of up to 500 m/min. This paper outlines the historical background of vortex spinning technology, the spinning principle and the structure of the yarn spun on this system, as well as the factors having impacts on the yarn quality and hence on the end use properties. In addition, the properties of the vortex yarns and fabrics are evaluated in comparison to other spun yarns and fabrics. Finally, the paper deals with the economics of this novel system. DA - 2012/9// PY - 2012/9// DO - 10.1080/00405167.2012.739345 VL - 44 IS - 3-4 SP - 141-174 J2 - Textile Progress LA - en OP - SN - 0040-5167 1754-2278 UR - http://dx.doi.org/10.1080/00405167.2012.739345 DB - Crossref KW - vortex spun yarn KW - air-jet KW - spinning KW - MVS ER - TY - JOUR TI - Effect of accelerated point distribution on sliver irregularity. Part II: optimization of draft settings in two-zone roller drafting system AU - Lin, Qian AU - Oxenham, William AU - Yu, Chongwen T2 - Journal of the Textile Institute AB - Abstract Accelerated point distribution plays a dominant role in discussing sliver irregularity in drafting. This paper, which is based on a theory developed in an earlier publication, proposes a new method to optimize the draft settings using the minimum coefficient of variation (CV) of fiber accelerated point. The new approach offers advantages over the traditional regressed optimal drafted settings (to yield the least weight variation in drafted slivers) and does not need extensive laboratory trials. Keywords: roller draftaccelerated point distributiondraft settingsliver weight variation Acknowledgements We would like to thank Timothy Pleasants, Dzung Nguyen, and Teresa White from College of Textiles in North Carolina State University for supplying the materials and for assisting with our experiments. This research was supported by Shu Guang project of Shanghai Municipal Education Commission and Shanghai Education Development Foundation (Grant No. 10GG17). DA - 2012/5// PY - 2012/5// DO - 10.1080/00405000.2011.590009 VL - 103 IS - 5 SP - 558-564 J2 - Journal of The Textile Institute LA - en OP - SN - 0040-5000 1754-2340 UR - http://dx.doi.org/10.1080/00405000.2011.590009 DB - Crossref KW - roller draft KW - accelerated point distribution KW - draft setting KW - sliver weight variation ER - TY - JOUR TI - Generation of cotton fiber length probability density function with length measures AU - Lin, Qian AU - Xing, Mingjie AU - Oxenham, William AU - Yu, Chongwen T2 - Journal of the Textile Institute AB - This report describes an investigation into the generation of fiber length distributional function using a limited number of length measurements. Based on the experimental data, the correlation between fiber length statistics (the calculated mean value and variance) and length measures (tested short fiber content, span lengths, etc.) was identified by employing the stepwise regression analysis, and this was necessary to describe the location and dispersion of the fiber length distribution. Then, a finite mixture model was adopted to generate the probability density function of fiber length. This paper concludes with a presentation of the approach to determine the probability density function of cotton fiber length. It is shown that the calculated short fiber contents and upper‐quartile length from the probability density function fit the experimental values well. DA - 2012/2// PY - 2012/2// DO - 10.1080/00405000.2011.566005 VL - 103 IS - 2 SP - 225-230 J2 - Journal of the Textile Institute LA - en OP - SN - 0040-5000 1754-2340 UR - http://dx.doi.org/10.1080/00405000.2011.566005 DB - Crossref KW - fiber length measures KW - length statistics KW - probability density function KW - stepwise regression KW - finite mixture model ER - TY - JOUR TI - Effect of Chemical and Physical Cross-Linking on Tensile Characteristics of Solution-Blown Soy Protein Nanofiber Mats AU - Sinha-Ray, S. AU - Khansari, S. AU - Yarin, A. L. AU - Pourdeyhimi, B. T2 - Industrial & Engineering Chemistry Research AB - Solution-blown soy protein/nylon 6 nanofibers, 40/60 and 50/50 wt/wt %, were collected on a rotating aluminum drum in order to form a mat. The collected fiber mats were bonded both chemically (using aldehydes and ionic cross-linkers) and physically (by means of wet and thermal treatment) to increase the tensile strength to increase the range of application of such green nonwovens. Chemical cross-linkers bond different amino groups, primary amides, and sulfhydryl groups in protein structure. This is beneficial for the enhancement of tensile strength. Such mechanical properties of soy-protein-containing nanofiber mats as Young’s modulus, yield stress, and maximum stress and strain at rupture were measured for different cross-linkers at different contents. Overall, higher contents of cross-linking agents in soy protein nanofiber mats resulted in nanofibers with higher strength which was accompanied by a less plastic behavior. Treatment with ionic cross-linkers resulted in nanofiber mats with higher Young’s modulus of the mats. Covalent bonds formed by aldehyde groups had a smaller effect on the mat strength. As cross-linked nanofibers were exposed to heat, the bonds formed between amino groups in the fibers were broken and they became less aggregated. The overall increase of about 50% in tensile strength as a result of thermal bonding under compression was observed. In addition, wet conglutination of soy protein/nylon 6 nanofiber mats for 24 h under 6 kPa pressure led to partial physical cross-linking of nanofibers and, consequently, to a 65% increase in Young’s modulus. Solution-blown soy protein/nylon 6 nanofiber mats were also subjected to aging in water for 1 h at 80 °C. An enhancement in the tensile strength of soy protein nanofiber mats was revealed after the exposure to water, as well as a slight plasticizing effect. DA - 2012/11/9/ PY - 2012/11/9/ DO - 10.1021/ie302359x VL - 51 IS - 46 SP - 15109-15121 J2 - Ind. Eng. Chem. Res. LA - en OP - SN - 0888-5885 1520-5045 UR - http://dx.doi.org/10.1021/ie302359x DB - Crossref ER - TY - JOUR TI - A macroscale model for simulating pressure drop and collection efficiency of pleated filters over time AU - Fotovati, S. AU - Tafreshi, H. Vahedi AU - Pourdeyhimi, B. T2 - Separation and Purification Technology AB - In this work, a computationally affordable macroscale model is developed to simulate the instantaneous collection efficiency and pressure drop of pleated depth filters. The numerical scheme presented here allows for the deposition of particles inside the fibrous fabric of a pleated filter, and accordingly varies its permeability and capture efficiency to simulate aging of the filter over time. This has been accomplished by developing a series of in-house subroutines that remarkably enhance the capabilities of the commercially available computational fluid dynamics code from ANSYS. This model is used to quantify the influence of pleat count, particle diameter, and flow velocity on the instantaneous performance of pleated filters with V-shaped pleats. Our results indicate that increasing the number of pleats reduces the rate of increase of a filter’s pressure drop and capture efficiency. Predictions of our model have been compared against available experimental data, and good agreement has been observed. DA - 2012/9// PY - 2012/9// DO - 10.1016/j.seppur.2012.07.009 VL - 98 SP - 344-355 J2 - Separation and Purification Technology LA - en OP - SN - 1383-5866 UR - http://dx.doi.org/10.1016/j.seppur.2012.07.009 DB - Crossref KW - Modeling filtration KW - Pleated filters KW - Dust-load simulation ER - TY - JOUR TI - Computation of mechanical anisotropy in thermally bonded bicomponent fibre nonwovens AU - Demirci, Emrah AU - Acar, Memiş AU - Pourdeyhimi, Behnam AU - Silberschmidt, Vadim V. T2 - Computational Materials Science AB - Having a unique microstructure composed of randomly-oriented polymer-based fibres, nonwovens exhibit complex deformation characteristics. The most prominent one is the mechanical anisotropy leading to their direction-dependent deformation behaviour. This paper focuses on mechanical anisotropy of thermally bonded bicomponent fibre nonwovens with polymer-based bicomponent core/sheath fibres. A relation between mechanical anisotropy of these nonwovens and random orientation of their fibres is developed in this study. Random orientation of individual fibres is quantified in terms of the orientation distribution function (ODF) in order to determine the material’s anisotropy. The ODF is obtained by analysing the data acquired with scanning electron microscopy or X-ray micro-computed tomography using digital image processing techniques based on the Hough transform. A numerical tool is developed to perform this analysis and determine the anisotropic parameters in order to define direction-dependency of the structure’s mechanical properties. Finally, anisotropic parameters of various nonwovens computed with the introduced numerical approach are compared with those obtained from tensile tests applied in machine and cross directions of nonwovens. DA - 2012/2// PY - 2012/2// DO - 10.1016/j.commatsci.2011.01.033 VL - 52 IS - 1 SP - 157-163 J2 - Computational Materials Science LA - en OP - SN - 0927-0256 UR - http://dx.doi.org/10.1016/j.commatsci.2011.01.033 DB - Crossref KW - Thermally bonded nonwoven KW - Bicomponent fibre KW - Orientation distribution function KW - Mechanical anisotropy KW - Digital image processing KW - Hough transform ER - TY - JOUR TI - 基于经验模态分解的并列双圆柱绕流信号处理 T2 - 实验室研究与探索 DA - 2012/6// PY - 2012/6// DO - 10.3969/j.issn.1006-7167.2012.06.002 ER - TY - JOUR TI - Nanofiber-based energy-storage materials T2 - Abstracts of Papers of the American Chemical Society DA - 2012/// PY - 2012/// UR - https://publons.com/publon/7178358/ ER - TY - JOUR TI - The effect of vitronectin on the differentiation of embryonic stem cells in a 3D culture system AU - Heydarkhan-Hagvall, S. AU - Gluck, J.M. AU - Delman, C. AU - Jung, M. AU - Ehsani, N. AU - Full, S. AU - Shemin, R.J. T2 - Biomaterials AB - While stem cell niches in vivo are complex three-dimensional (3D) microenvironments, the relationship between the dimensionality of the niche to its function is unknown. We have created a 3D microenvironment through electrospinning to study the impact of geometry and different extracellular proteins on the development of cardiac progenitor cells (Flk-1(+)) from resident stem cells and their differentiation into functional cardiovascular cells. We have investigated the effect of collagen IV, fibronectin, laminin and vitronectin on the adhesion and proliferation of murine ES cells as well as the effects of these proteins on the number of Flk-1(+) cells cultured in 2D conditions compared to 3D system in a feeder free condition. We found that the number of Flk-1(+) cells was significantly higher in 3D scaffolds coated with laminin or vitronectin compared to colIV-coated scaffolds. Our results show the importance of defined culture systems in vitro for studying the guided differentiation of pluripotent embryonic stem cells in the field of cardiovascular tissue engineering and regenerative medicine. DA - 2012/// PY - 2012/// DO - 10.1016/j.biomaterials.2011.11.065 VL - 33 IS - 7 SP - 2032-2040 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84855723930&partnerID=MN8TOARS KW - Extracellular matrix KW - Niche KW - Cardiovascular tissue engineering KW - Stem cell KW - Scaffold ER - TY - JOUR TI - Stem Cell Extracellular Matrix Interactions in Three- Dimensional System via Integrins T2 - Journal of Regenerative Medicine AB - Stem Cell Extracellular Matrix Interactions in Three- Dimensional System via Integrins Cells of all types interact with the extracellular matrix (ECM) through integrin-mediated interactions. Adhesion of embryonic stem (ES) cells is necessary for differentiation. We have characterized integrin expression of undifferentiated mES cells and established a system of evaluating the ECM-integrin interactions in three-dimension (3D) using electrospun scaffolds. We observed a higher proliferation rate at early time points in conventional 2D culture with various ECM proteins (collagen IV, laminin, fibronectin, vitronectin) as compared to 3D conditions. At later time points, we observed higher proliferations in 3D culture conditions compared to 2D culture conditions. We also detected the importance of α5, αV, β1, β5 and αVβ5 integrin subunits for cellular adhesion in 3D conditions using a cellular adhesion assay. DA - 2012/// PY - 2012/// DO - 10.4172/2325-9620.1000107 UR - http://dx.doi.org/10.4172/2325-9620.1000107 ER - TY - JOUR TI - alpha-Fe2O3 nanoparticle-loaded carbon nanofibers as stable and high-capacity anodes for rechargeable lithium-ion batteries AU - Ji, L. W. AU - Toprakci, O. AU - Alcoutlabi, M. AU - Yao, Y. F. AU - Li, Y. AU - Zhang, S. AU - Guo, B. K. AU - Lin, Z. AU - Zhang, X. W. T2 - ACS Applied Materials & Interfaces DA - 2012/// PY - 2012/// VL - 4 ER - TY - JOUR TI - Carbon nanotube-loaded electrospun LiFePO4/carbon composite nanofibers as stable and binder-free cathodes for rechargeable lithium-ion batteries AU - Toprakci, O. AU - Toprakci, H. A. K. AU - Ji, L. W. AU - Xu, G. J. AU - Lin, Z. AU - Zhang, X. W. T2 - ACS Applied Materials & Interfaces DA - 2012/// PY - 2012/// VL - 4 ER - TY - JOUR TI - Reactivity of a σ,σ,σ,σ-Tetraradical: The 2,4,6-Tridehydropyridine Radical Cation AU - Gallardo, Vanessa A. AU - Jankiewicz, Bartłomiej J. AU - Vinueza, Nelson R. AU - Nash, John J. AU - Kenttämaa, Hilkka I. T2 - Journal of the American Chemical Society AB - The 2,4,6-tridehydropyridine radical cation, an analogue of the elusive 1,2,3,5-tetradehydrobenzene, was generated in the gas phase and its reactivity examined. Surprisingly, the tetraradical was found not to undergo radical reactions. This behavior is rationalized by resonance structures hindering fast radical reactions. This makes the cation highly electrophilic, and it rapidly reacts with many nucleophiles by quenching the N–C ortho-benzyne moiety, thereby generating a relatively unreactive meta-benzyne analogue. DA - 2012/1/23/ PY - 2012/1/23/ DO - 10.1021/ja209068z VL - 134 IS - 4 SP - 1926-1929 J2 - J. Am. Chem. Soc. LA - en OP - SN - 0002-7863 1520-5126 UR - http://dx.doi.org/10.1021/ja209068z DB - Crossref ER - TY - JOUR TI - Substituent Effects on the Nonradical Reactivity of 4-Dehydropyridinium Cation AU - Jankiewicz, Bartłomiej J. AU - Gao, Jinshan AU - Reece, Jennifer N. AU - Vinueza, Nelson R. AU - Narra, Padmaja AU - Nash, John J. AU - Kenttämaa, Hilkka I. T2 - The Journal of Physical Chemistry A AB - Recent studies have shown that the reactivity of the 4-dehydropyridinium cation significantly differs from the reactivities of its isomers toward tetrahydrofuran. While only hydrogen atom abstraction was observed for the 2- and 3-dehydropyridinium cations, nonradical reactions were observed for the 4-isomer. In order to learn more about these reactions, the gas-phase reactivities of the 4-dehydropyridinium cation and several of its derivatives toward tetrahydrofuran were investigated in a Fourier transform ion electron resonance mass spectrometer. Both radical and nonradical reactions were observed for most of these positively charged radicals. The major parameter determining whether nonradical reactions occur was found to be the electron affinity of the radicals—only those with relatively high electron affinities underwent nonradical reactions. The reactivities of the monoradicals are also affected by hydrogen bonding and steric effects. DA - 2012/3/15/ PY - 2012/3/15/ DO - 10.1021/jp2101557 VL - 116 IS - 12 SP - 3089-3093 J2 - J. Phys. Chem. A LA - en OP - SN - 1089-5639 1520-5215 UR - http://dx.doi.org/10.1021/jp2101557 DB - Crossref ER - TY - JOUR TI - Identification and Counting of Oxygen Functionalities and Alkyl Groups of Aromatic Analytes in Mixtures by Positive-Mode Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry Coupled with High-Performance Liquid Chromatography AU - Amundson, Lucas M. AU - Gallardo, Vanessa A. AU - Vinueza, Nelson R. AU - Owen, Benjamin C. AU - Reece, Jennifer N. AU - Habicht, Steven C. AU - Fu, Mingkun AU - Shea, Ryan C. AU - Mossman, Allen B. AU - Kenttämaa, Hilkka I. T2 - Energy & Fuels AB - A tandem mass spectrometric method using a commercial linear quadrupole ion trap (LQIT) mass spectrometer and another LQIT coupled with a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer is described for the identification and counting of different oxygen-containing functionalities and alkyl groups in unknown aromatic analytes. A total of 64 aromatic model compounds were evaporated and ionized via positive-mode atmospheric pressure chemical ionization (APCI). Ionization of the model compounds primarily results in the formation of protonated molecules, [M + H]+. In some cases, the molecular radical cation, [M]+ •, and/or a fragment ion, [M – H]+, are formed instead. Only in one case, no ions were observed near the m/z value of the molecular ion, and the ion with the greatest m/z value is a fragment ion, [M + H – H2O]+. Once ionized, the ions were subjected to multiple isolation and collision-activated dissociation (CAD) events until no more fragmentation was observed (up to MS5). In most cases, all functionalities were sequentially cleaved, one or more at a time, by the CAD events. The type of neutral molecule cleaved and the number of times that it was cleaved facilitate the identification and counting of the functionalities. The method was successfully used in concert with high-performance liquid chromatography (HPLC). The HPLC retention times offer further structural information for the analytes. This methodology benefits the chemical, pharmaceutical, and biofuels industries by facilitating the identification of previously unknown compounds directly in complex mixtures, such as crude products of chemical processes, drug metabolites, and lignin degradation products. DA - 2012/4/26/ PY - 2012/4/26/ DO - 10.1021/ef2019098 VL - 26 IS - 5 SP - 2975-2989 J2 - Energy Fuels LA - en OP - SN - 0887-0624 1520-5029 UR - http://dx.doi.org/10.1021/ef2019098 DB - Crossref ER - TY - JOUR TI - Reactivity of the 4,5-Didehydroisoquinolinium Cation AU - Vinueza, Nelson R. AU - Archibold, Enada F. AU - Jankiewicz, Bartłomiej J. AU - Gallardo, Vanessa A. AU - Habicht, Steven C. AU - Aqueel, Mohammad Sabir AU - Nash, John J. AU - Kenttämaa, Hilkka I. T2 - Chemistry - A European Journal AB - Abstract The chemical properties of a 1,8‐didehydronaphthalene derivative, the 4,5‐didehydroisoquinolinium cation, were examined in the gas phase in a dual‐cell Fourier‐transform ion cyclotron resonance (FT‐ICR) mass spectrometer. This is an interesting biradical because it has two radical sites in close proximity, yet their coupling is very weak. In fact, the biradical is calculated to have approximately degenerate singlet and triplet states. This biradical was found to exclusively undergo radical reactions, as opposed to other related biradicals with nearby radical sites. The first bond formation occurs at the radical site in the 4‐position, followed by that in the 5‐position. The proximity of the radical sites leads to reactions that have not been observed for related mono‐ or biradicals. Interestingly, some ortho ‐benzynes have been found to yield similar products. Since ortho ‐benzynes do not react via radical mechanisms, these products must be especially favorable thermodynamically. DA - 2012/6/12/ PY - 2012/6/12/ DO - 10.1002/chem.201103628 VL - 18 IS - 28 SP - 8692-8698 J2 - Chem. Eur. J. LA - en OP - SN - 0947-6539 UR - http://dx.doi.org/10.1002/chem.201103628 DB - Crossref KW - biradicals KW - didehydronaphthalene KW - FT-ICR KW - ion-molecule reactions KW - reactive intermediates ER - TY - JOUR TI - Multifunctional and durable nanofiber-fabric-layered composite for protective application AU - Shi, Quan AU - Vitchuli, Narendiran AU - Nowak, Joshua AU - Jiang, Shan AU - Caldwell, Jane M. AU - Breidt, Frederick AU - Bourham, Mohamed AU - Zhang, Xiangwu AU - McCord, Marian T2 - Journal of Applied Polymer Science AB - A multifunctional and durable nanofiber-fabric-layered composite (NFLC) material was prepared by depositing electrospun Ag/PAN hybrid nanofibers onto a Nylon/cotton 50: 50 fabric substrate. The NFLCs showed excellent aerosol barrier efficiency and good air/moisture permeability. In addition, they showed excellent antibacterial efficiency by completely inhibiting the growth of both Gram-negative E. coli and Gram-positive S. aureus. The interfacial adhesion between the nanofiber layer and fabric substrate was significantly improved by atmospheric plasma pretreatment of the substrate. The resultant NFLCs showed excellent resistance to peeling, twisting, and flexing forces. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 DA - 2012/9/1/ PY - 2012/9/1/ DO - 10.1002/app.38465 VL - 128 IS - 2 SP - 1219-1226 J2 - J. Appl. Polym. Sci. LA - en OP - SN - 0021-8995 UR - http://dx.doi.org/10.1002/app.38465 DB - Crossref KW - nanostructured polymers KW - textiles KW - biomedical applications ER - TY - CONF TI - Multiscale simulations of the adsorption of aqueous PEOnPPOmPEOn triblock copolymers onto hydrophobic and hydrophilic polymer surfaces AU - Pasquinelli, Melissa A AU - He, Feng AU - Liu, Hongyi AU - Rojas, Orlando J T2 - AMER CHEMICAL SOC 1155 16TH ST, NW, WASHINGTON, DC 20036 USA C2 - 2012/// C3 - ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY DA - 2012/// VL - 244 ER - TY - CONF TI - Molecular dynamics simulations of the thermal stability of oleic acid films on a crystalline cellulose surface AU - Quddus, Mir AAR AU - Rojas, Orlando J AU - Pasquinelli, Melissa A T2 - AMER CHEMICAL SOC 1155 16TH ST, NW, WASHINGTON, DC 20036 USA C2 - 2012/// C3 - ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY DA - 2012/// VL - 243 ER - TY - BOOK TI - Molecular dynamics simulations of the thermal stability of crystalline cellulose surfaces coated with oleic acid AU - Quddus, Mir A. A. R. AU - Rojas, Orlando J. AU - Pasquinelli, Melissa A. AB - The thermal stability of different types of oleic acid films on a crystalline cellulose surface has been investigated through molecular dynamics simulations. The thin film was observed to become disordered upon heating, resulting in the evaporation of oleic acid molecules. This effect is expected to contribute to the performance of cellulose, for example in packaging, where food contamination can be facilitated. In contrast, double layers and annealed coatings remained stable over the temperature range tested in this simulation. DA - 2012/// PY - 2012/// DO - 10.1021/bk-2012-1107.ch010 VL - 1107 PB - na SE - 191-208 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84898630112&partnerID=MN8TOARS ER - TY - CHAP TI - Molecular Dynamics Simulations of Nano-Bio Materials AU - Pasquinelli, Melissa A AU - Yingling, Yaroslava G T2 - Encyclopedia of Nanotechnology PY - 2012/// SP - 1454-1463 PB - Springer, Dordrecht ER - TY - CONF TI - Characteristics of interfaces in ABA triblock copolymer/homopolymer systems from simulations and theory AU - Tallury, Syamal S AU - Pasquinelli, Melissa A AU - Spontak, Richard J T2 - AMER CHEMICAL SOC 1155 16TH ST, NW, WASHINGTON, DC 20036 USA C2 - 2012/// C3 - ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY DA - 2012/// VL - 244 ER - TY - JOUR TI - Carbon Nanotube and Polyimide Interactions: A Molecular Dynamics Study AU - Jiang, Q. AU - Tallury, S. AU - Pasquinelli, M. T2 - Polymer Preprints DA - 2012/// PY - 2012/// VL - 53 IS - 2 SP - 71 ER - TY - JOUR TI - COMPARATIVE THREADING OF GUEST POLYMERS BY HOST CYCLODEXTRINS: MODELING AND EXPERIMENTAL OBSERVATIONS AU - Gurarslan, Alper AU - Pasquinelli, Melissa A AU - Tonelli, Alan E T2 - Polymer Preprints DA - 2012/// PY - 2012/// VL - 53 IS - 1 SP - 406 ER - TY - BOOK TI - In silico strategies for modeling stereoselective metabolism of pyrethroids AU - Chang, Daniel T. AU - Goldsmith, Michael-Rock AU - Tornero-Velez, Rogelio AU - Tan, Yu-Mei AU - Grulke, Christopher M. AU - Chen, Ling-Jen AU - Ulrich, Elin M. AU - Lindstrom, Andrew B. AU - Pasquinelli, Melissa A. AU - Rabinowitz, James R. AU - Dary, Curtis C. AB - In silico methods are invaluable tools to researchers seeking to understand and predict metabolic processes within PBPK models. Even though these methods have been successfully utilized to predict and quantify metabolic processes, there are many challenges involved. Stereochemical processes are a particular challenge since they require computational methods that can elucidate 3D structures and their inherent conformational dependence within a biological context. Developed methods to estimate stereoselective metabolic hydrolysis in mammals are presented to aid PBPK modelers in determining qualitative as well as quantitative relationships among the chiral pyrethroid pesticides. We illustrate a case example of rat serum carboxylesterase (rsCE)-mediated hydrolysis of 27 pyrethroid stereisomers elucidated through a proposed three-step in silico workflow. The methodology involves (i) a pharmacophore structural qualifier/filter to determine whether or not a particular stereoisomer is indeed a viable substrate, and (ii) a mechanism-specific quantitative structure activity relationship (QSAR) to predict metabolic rate constants. Our strategy extends the utility of pharmacophore filters in the reduction of misclassification of mechanistically competent substrates, while strengthening the utility of QSAR models within PK/PD model development. DA - 2012/// PY - 2012/// DO - 10.1021/bk-2012-1099.ch016 VL - 1099 PB - American Chemical Society (ACS) SE - 245-269 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84905658108&partnerID=MN8TOARS ER - TY - JOUR TI - The Soft-Confined Method for Creating Molecular Models of Amorphous Polymer Surfaces AU - Liu, Hongyi AU - Li, Yan AU - Krause, Wendy E. AU - Rojas, Orlando J. AU - Pasquinelli, Melissa A. T2 - The Journal of Physical Chemistry B AB - ADVERTISEMENT RETURN TO ISSUEPREVAddition/CorrectionNEXTORIGINAL ARTICLEThis notice is a correctionThe Soft-Confined Method for Creating Molecular Models of Amorphous Polymer SurfacesHongyi Liu, Yan Li, Wendy E. Krause, Orlando J. Rojas*, and Melissa A. Pasquinelli*Cite this: J. Phys. Chem. B 2012, 116, 8, 2633Publication Date (Web):February 16, 2012Publication History Published online16 February 2012Published inissue 1 March 2012https://doi.org/10.1021/jp301233xCopyright © 2012 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views290Altmetric-Citations1LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (96 KB) Get e-Alerts Get e-Alerts DA - 2012/2/16/ PY - 2012/2/16/ DO - 10.1021/jp301233x VL - 116 IS - 8 SP - 2633-2633 J2 - J. Phys. Chem. B LA - en OP - SN - 1520-6106 1520-5207 UR - http://dx.doi.org/10.1021/jp301233x DB - Crossref ER - TY - JOUR TI - Experimental and computational study of the effect of alcohols on the solution and adsorption properties of a nonionic symmetric triblock copolymer AU - Liu, Xiaomeng AU - He, Feng AU - Salas, Carlos AU - Pasquinelli, Melissa A. AU - Genzer, Jan AU - Rojas, Orlando J. T2 - Journal of Physical Chemistry B AB - This study investigates the effect of alcohols on the solution and adsorption properties of symmetric triblock nonionic copolymers comprising blocks of ethylene oxide (EO) and propylene oxide (PO) (EO(37)PO(56)EO(37)). The cloud point, surface tension, critical micelle concentration (CMC), and maximum packing at the air-water interface are determined, and the latter is compared to the amount of polymer that adsorbs from solution onto polypropylene (PP) and cellulose surfaces. The interaction energy and radius of micelles are calculated by using molecular dynamics (MD) simulations. Equivalent MD bead parameters were used in dynamic density functional theory (DDFT) simulations to study the influence of alcohols on the phase behavior of EO(37)PO(56)EO(37) and its adsorption on PP from aqueous solutions. The simulation results agree qualitatively with the experimental observations. Ethanol acts as a good cosolvent for EO(37)PO(56)EO(37) and reduces the amount of EO(37)PO(56)EO(37) that adsorbs on PP surfaces; however, little or no influence is observed on the adsorption on cellulose. Interestingly, longer chain alcohols, such as 1-pentanol, produce the opposite effect. Overall, the solution and adsorption properties of nonionic symmetric triblock copolymers in the presence of alcohols are rationalized by changes in solvency and the hydrophobic effect. DA - 2012/// PY - 2012/// DO - 10.1021/jp207190c VL - 116 IS - 4 SP - 1289-1298 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84863015015&partnerID=MN8TOARS ER - TY - JOUR TI - Nanofiber-based energy-storage materials AU - Zhang, Xiangwu T2 - Abstracts of Papers of the American Chemical Society DA - 2012/// PY - 2012/// VL - 243 ER - TY - JOUR TI - Li₂MnSiO₄ Carbon Composite Nanofibers as a High-Capacity Cathode Material for Li-Ion Batteries AU - Zhang, Shu AU - Li, Ying AU - Xu, Guanjie AU - Li, Shuli AU - Lu, Yao AU - Topracki, Ozan AU - Zhang, Xiangwu T2 - Soft Nanoscience Letters AB - Li2MnSiO4 has an extremely high theoretical capacity of 332 mAh?g?1. However, only around half of this capacity has been realized in practice and the capacity retention during cycling is also low. In this study, Li2MnSiO4/carbon composite nanofibers were prepared by a combination of electrospinning and heat treatment. The one-dimensional continuous carbon nanofiber matrix serves as long-distance conductive pathways for both electrons and ions. The composite nanofiber structure avoids the aggregation of Li2MnSiO4 particles, which in turn enhances the electrode conductivity and promotes the reaction kinetics. The resultant Li2MnSiO4/carbon composite nanofibers were used as the cathode material for Li-ion batteries, and they delivered high charge and discharge capacities of 218 and 185 mAh?g?1, respectively, at the second cycle. In addition, the capacity retention of Li2MnSiO4 at the first 20th cycles increased from 37% to 54% in composite nanofibers. DA - 2012/// PY - 2012/// DO - 10.4236/snl.2012.23010 VL - 02 IS - 03 SP - 54-57 ER - TY - JOUR TI - High-rate capability of LiFePO(4) cathode materials containing Fe(2)P and trace carbon AU - Yin, Y. H. AU - Gao, M. X. AU - Pan, H. G. AU - Shen, L. K. AU - Ye, X. AU - Liu, Y. F. AU - Fedkiw, P. S. AU - Zhang, X. W. T2 - Journal of Power Sources AB - Carbon coating and nano-scale particle size are two impactful factors in improving the rate capability of LiFePO4 cathode materials for lithium-ion batteries. However, both factors decrease the tap density of the materials and are possibly causing unfavorable effect on the volumetric capacity of the cathode materials and thus the batteries, which is undesirable in commercial application. In the present study, LiFePO4 materials with moderate particle size of sub-micron and trace carbon content (0.5–0.9 wt.%) are synthesized by a mechanical activation method. High-electronic conductivity iron phosphides (Fe2P/FeP) are in situ introduced into the LiFePO4 materials and the amount is modified by the calcination temperature. Electrochemical testing shows that Fe2P/FeP plays an important role in improving the high-rate capability of LiFePO4 with moderate particle size. The product calcined at 700 °C, which has a high-tap density of 1.37 g cm−3 correlating to a specific surface area approximately of 4 m2 g−1, possesses discharge capacities of 110 and 100 mAh g−1 at discharge rates of 5 C and 10 C, respectively. The introduction of Fe2P/FeP in an amount of ca. 5 wt.% rather than carbon coating and the moderate particle size of LiFePO4 are promising approaches to obtain LiFePO4 cathode material of high-rate capability without unduly compromising its volumetric capacity. DA - 2012/// PY - 2012/// DO - https://doi.org/10.1016/j.jpowsour.2011.10.042 VL - 199 ER - TY - JOUR TI - High-capacity Li2Mn0.8Fe0.2SiO4/carbon composite nanofiber cathodes for lithium-ion batteries AU - Zhang, S. AU - Li, Y. AU - Xu, G. J. AU - Li, S. L. AU - Lu, Y. AU - Toprakci, O. AU - Zhang, X. W. T2 - Journal of Power Sources AB - Li2MnSiO4 has been considered as a promising cathode material with an extremely high theoretically capacity of 332 mAh g−1. However, due to its low intrinsic conductivity and poor structural stability, only about half of the theoretical capacity has been realized in practice and the capacity decays rapidly during cycling. To realize the high capacity and improve the cycling performance, Li2Mn0.8Fe0.2SiO4/carbon composite nanofibers were prepared by the combination of iron doping and electrospinning. X-ray diffraction, scanning electron microscope, and transmission electronic microscope were applied to characterize the Li2Mn0.8Fe0.2SiO4/carbon nanofibers. It was found that Li2Mn0.8Fe0.2SiO4 nanoparticles were embedded into continuous carbon nanofiber matrices, which formed free-standing porous mats that could be used as binder-free cathodes. The iron doping improved the conductivity and purity of the active material, and the carbon nanofiber matrix facilitated ion transfer and charge diffusion. As a result, Li2Mn0.8Fe0.2SiO4/carbon nanofiber cathodes showed promising improvement on reversible capacity and cycling performance. DA - 2012/// PY - 2012/// DO - https://doi.org/10.1016/j.jpowsour.2012.04.011 VL - 213 ER - TY - JOUR TI - Cr-doped Li2MnSiO4/carbon composite nanofibers as high-energy cathodes for Li-ion batteries AU - Zhang, Shu AU - Lin, Zhan AU - Ji, Liwen AU - Li, Ying AU - Xu, Guanjie AU - Xue, Leigang AU - Li, Shuli AU - Lu, Yao AU - Toprakci, Ozan AU - Zhang, Xiangwu T2 - Journal of Materials Chemistry AB - Li2MnSiO4 with an extremely high theoretical capacity of 332 mA h g−1 has recently gained tremendous interest. However, only around half of this capacity has been realized in practice and the cycling performance is also poor due to the low intrinsic conductivity and unsatisfactory structure stability. In this study, Li2Mn(1−x)CrxSiO4/carbon composite nanofibers are prepared by the combination of electrospinning and Cr doping. The electrospinning process leads to the formation of a conductive carbon nanofiber matrix, which provides fast ion transport and charge transfer. Cr doping further improves crystal structure stability by increasing the unit cell volume and inducing defects in the lattice. The resultant Li2Mn(1−x)CrxSiO4/carbon composite nanofibers exhibit a high discharge capacity of 314 mA h g−1 at the 5th cycle and stable cycling performance. DA - 2012/// PY - 2012/// DO - 10.1039/c2jm32213g VL - 22 IS - 29 SP - 14661-14666 UR - https://publons.com/publon/674389/ ER - TY - JOUR TI - Polyvinylidene fluoride-co-chlorotrifluoroethylene and polyvinylidene fluoride-co-hexafluoropropylene nanofiber-coated polypropylene microporous battery separator membranes AU - Lee, Hun AU - Alcoutlabi, Mataz AU - Watson, Jill V. AU - Zhang, Xiangwu T2 - Journal of Polymer Science Part B: Polymer Physics AB - Abstract Nanofiber‐coated polypropylene (PP) separator membranes were prepared by coating a Celgard® microporous PP membrane with electrospun polyvinylidene fluoride‐ co ‐chlorotrifluoroethylene (PVDF‐ co ‐CTFE) and PVDF‐ co ‐CTFE/polyvinylidene fluoride‐ co ‐hexafluoropropylene (PVDF‐ co ‐HFP) nanofibers. Three PVDF polymer solutions of varying compositions were used in the preparation of the nanofiber coatings. Two of the polymer solutions were PVDF‐ co ‐CTFE blends made using different types of PVDF‐ co ‐HFP copolymers. The PVDF‐ co ‐CTFE and PVDF‐ co ‐CTFE/PVDF‐ co ‐HFP blend nanofiber coatings have been found to have comparable adhesion to the PP microporous membrane substrate. The electrolyte uptakes and separator–electrode adhesion properties of nanofiber‐coated membranes were evaluated. Both the electrolyte uptake and the separator–electrode adhesion were improved by the nanofiber coatings. The improvement in electrolyte update capacity is not only related to the gelation capability of the PVDF copolymer nanofibers, but also attributed to the increased porosity and capillary effect on nanofibrous structure of the electrospun nanofiber coatings. Enhancement of the separator–electrode adhesion was owing to the adhesion properties of the copolymer nanofiber coatings. Compared with the PVDF‐ co ‐CTFE/PVDF‐ co ‐HFP blend nanofiber coatings studied, the PVDF‐ co ‐CTFE coating was more effective in improving the electrolyte uptake and separator–electrode adhesion. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 DA - 2012/11// PY - 2012/11// DO - 10.1002/polb.23216 VL - 51 IS - 5 SP - 349-357 KW - Adhesion KW - Coatings KW - Electrospinning KW - Lithium-ion batteries KW - Nanofibers KW - PVDF-co-CTFE KW - PVDF-co-HFP KW - Separators ER - TY - JOUR TI - Novel Atmospheric Plasma Enhanced Silk Fibroin Nanofiber/Gauze Composite Wound Dressings AU - Nawalakhe, R. AU - Vitchuli, N. AU - Shi, Q. AU - Bourham, M.A. AU - Zhang, X. AU - McCord, M.G. T2 - Journal of Fiber Bioengineering and Informatics DA - 2012/6// PY - 2012/6// DO - 10.3993/jfbi09201201 VL - 5 IS - 3 SP - 227-242 SN - 1940-8676 2617-8699 UR - http://dx.doi.org/10.3993/jfbi09201201 ER - TY - JOUR TI - Multifunctional and durable nanofiber-fabric-layered composite for protective application AU - Shi, Quan AU - Vitchuli, Narendiran AU - Nowak, Joshua AU - Jiang, Shan AU - Caldwell, Jane M. AU - Breidt, Frederick AU - Bourham, Mohamed AU - Zhang, Xiangwu AU - McCord, Marian T2 - Journal of Applied Polymer Science AB - Abstract The effect of filler surface treatment on the dynamic rheological behaviors of polystyrene filled with Sn–Pb alloy particles was tested below and above the melting temperature ( T m ) of the alloy. The mechanical relaxation relevant to the T m of the alloy in the composite was diminished by the filler surface pretreatment. In the whole temperature range of interest, there existed a secondary plateau of the storage modulus at low frequencies. The effect of alloy particle surface treatment on the plateau was related to the matter‐state change (from solid to liquid) of the alloy. Above the T m of the alloy, the surface treatment of the alloy affected the secondary plateau, but below the T m , it did not. The analyses of Cole–Cole diagrams of the systems suggested that untreated and pretreated alloy fillers all retarded the relaxation processes in the molten state of polystyrene below the T m of the alloy and that the relaxation process was separated into the high‐frequency relaxation of the phases and the low‐frequency relaxation of the droplets above the T m . The surface treatments of the alloy filler further enhanced this action. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3173–3179, 2002 DA - 2012/9/1/ PY - 2012/9/1/ DO - 10.1002/app.11352 VL - 128 IS - 2 SP - 1219-1226 KW - surfaces KW - rheology KW - composites KW - alloys KW - melting point ER - TY - CONF TI - Lithium-Ion Batteries: Amorphous Carbon Coating of Silicon-Carbon Nanofibers as Anode Materials C2 - 2012/8// C3 - 11th Annual NC State Summer Undergraduate Research Symposium DA - 2012/8// ER - TY - JOUR TI - The effect speed and replenishment flexibility has on overall costs of sourcing apparel products AU - Hartman, Lisa AU - Joines, Jeffrey A. AU - Thoney, Kristin A. AU - King, Russell E. T2 - Journal of the Textile Institute AB - This research investigates the sourcing of basic and seasonal garments as a function of lead time as well as the ability that providing in-season replenishment orders has on overall costs. Most sourcing decisions are made on the basis of the first cost of the garment with little regard to the potential impact of large hidden costs (i.e. lost sales, inventory costs, markdowns, etc.). A small survey administered to apparel manufacturers and retailers is used to gather perspectives on sourcing from various regions of the world. However, its primary purpose is to gather information and data to drive a variety of case studies. The Sourcing Simulator™ is used to determine the effect that lead times, forecasting error, product drift and seasonality have on retail performance (i.e. service levels, gross margins and inventory levels) for these case studies. Analysis is performed to attempt to quantify some of these hidden costs. Results show that choosing suppliers with shorter lead times provides significant advantages for basic goods as well as seasonal goods, which in some instances justify using more expensive suppliers in terms of first cost. These advantages take on the form of smaller inventory levels for achieving the same service, as well as minimizing the impact of errors in forecast and product mix for basic goods while increasing margins by using in-season replenishments for seasonal products. DA - 2012/6// PY - 2012/6// DO - 10.1080/00405000.2011.595106 VL - 103 IS - 6 SP - 604-621 KW - supply chain KW - sourcing decision KW - inventory models KW - lead time ER - TY - JOUR TI - Literature review on superhydrophobic self-cleaning surfaces produced by electrospinning AU - Sas, Iurii AU - Gorga, Russell E. AU - Joines, Jeff A. AU - Thoney, Kristin A. T2 - JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS AB - Abstract Self‐cleaning surface is potentially a very useful addition for many commercial products due to economic, aesthetic, and environmental reasons. Super‐hydrophobic self‐cleaning, also called Lotus effect, utilizes right combination of surface chemistry and roughness to force water droplets to form high contact angle on a surface, easily roll off a surface and pick up dirt particles on its way. Electrospinning is a promising technique for creation of superhydrophobic self‐cleaning surfaces owing to a wide set of parameters that allow effectively controlling roughness of resulted webs. This article gives a brief introduction to the theory of super‐hydrophobic self‐cleaning and basic principles of the electrospinning process and reviews the scientific literature where electrospinning was used to create superhydrophobic surfaces. The article reviewed are categorized into several groups and their results are compared in terms of superhydrophobic properties. Several issues with current state of the art and highlights of important areas for future research are discussed in the conclusion. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 DA - 2012/6/15/ PY - 2012/6/15/ DO - 10.1002/polb.23070 VL - 50 IS - 12 SP - 824-845 SN - 1099-0488 KW - biomimetic KW - electrospinning KW - fibers KW - functionalization of polymers KW - lotus effects KW - microstructure KW - nanotechnology KW - self-cleaning KW - superhydrophobic KW - surfaces KW - textiles ER - TY - BOOK TI - Simulation Modeling with SIMIO: A Workbook AU - Joines, J.A. AU - Roberts, S.D. DA - 2012/// PY - 2012/// ET - 2nd PB - Sewickley, PA: SIMIO LLC ER - TY - JOUR TI - Translation between Heat Loss Measured Using Guarded Sweating Hot Plate, Sweating Manikin, and Physiologically Assessed Heat Stress of Firefighter Turnout Ensembles AU - Ross, Kevin AU - Barker, Roger AU - Deaton, A. Shawn T2 - PERFORMANCE OF PROTECTIVE CLOTHING AND EQUIPMENT, 9TH VOL: EMERGING ISSUES AND TECHNOLOGIES DA - 2012/// PY - 2012/// DO - 10.1520/stp104510 VL - 1544 SP - 27-47 SN - 0066-0558 KW - sweating manikin KW - heat stress KW - sweating hot plate KW - thermal manikin KW - total heat loss KW - thermal resistance KW - evaporative resistance KW - THL KW - physiological response ER - TY - JOUR TI - Interlaboratory Study of ASTM F2731, Standard Test Method for Measuring the Transmitted and Stored Energy of Firefighter Protective Clothing Systems AU - Deuser, L. AU - Barker, R. AU - Deaton, A. S. AU - Shepherd, A. T2 - PERFORMANCE OF PROTECTIVE CLOTHING AND EQUIPMENT, 9TH VOL: EMERGING ISSUES AND TECHNOLOGIES DA - 2012/// PY - 2012/// DO - 10.1520/stp104211 VL - 1544 SP - 188-201 SN - 0066-0558 KW - firefighting KW - interlaboratory study KW - protective clothing KW - textiles KW - turnout gear KW - stored energy ER - TY - JOUR TI - Factors Influencing the Uptake Rate of Passive Adsorbent Dosimeters Used in the Man-in-Simulant-Test AU - Ormond, R. Bryan AU - Barker, Roger AU - Beck, Keith AU - Thompson, Donald AU - Deaton, Shawn T2 - PERFORMANCE OF PROTECTIVE CLOTHING AND EQUIPMENT, 9TH VOL: EMERGING ISSUES AND TECHNOLOGIES DA - 2012/// PY - 2012/// DO - 10.1520/stp104205 VL - 1544 SP - 247-265 SN - 0066-0558 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84873388951&partnerID=MN8TOARS KW - passive adsorbent dosimeters KW - PADs KW - man-in-simulant-test KW - MIST KW - chem-/bio-ensemble KW - methyl salicylate KW - uptake rate KW - simulant concentration KW - adhesive KW - ASTM F2588 ER - TY - CONF TI - Extraction and utilization of hemicelluloses for new biomaterial applications AU - Salam, A. AU - Venditti, R. A. AU - Pawlak, J. J. AU - El-tahlawy, K. AU - Ayoub, A. C2 - 2012/// C3 - Proceeding of the 4th International Conference on Pulping, Papermaking and Biotechnology (ICPPB '12), vols. I and II DA - 2012/// SP - 885-890 ER - TY - JOUR TI - Developing a Thermal Sensor for Use in the Fingers of the PyroHands Fire Test System AU - Hummel, Alexander AU - Barker, Roger AU - Lyons, Kevin AU - Deaton, A. Shawn AU - Morton-Aslanis, John T2 - PERFORMANCE OF PROTECTIVE CLOTHING AND EQUIPMENT, 9TH VOL: EMERGING ISSUES AND TECHNOLOGIES DA - 2012/// PY - 2012/// DO - 10.1520/stp104207 VL - 1544 SP - 176-187 SN - 0066-0558 KW - fire test manikins KW - thermal sensors KW - flash fires KW - heat transfer KW - fire resistant gloves KW - thermal protective performance ER - TY - CONF TI - Moisture vapor barrier properties of biopolymers for packaging materials AU - Grewal, R. AU - Sweesy, W. AU - Jur, J. S. AU - Willoughby, J. AB - We present a review of current research focused on the use of biopolymers as viable packaging materials. We discuss polysaccharides, proteins, lipids, materials systems comprising edible coatings, and inorganic surface modification processes as they impact moisture barrier permeability properties. We give an overview of the fundamental factors that affect moisture vapor permeability (MVP), provide an overview of barrier properties for typical packaging materials on a common unit basis, and the MVP improvements made with evolving techniques. We explore some challenges and unknowns with surface modifications specific to altering the barrier properties of polymers derived from renewable resources. We provide some of the future directions in our own work to improve materials with inherently poor moisture vapor properties using the insights from this review as a road map. C2 - 2012/// C3 - Functional materials from renewable sources DA - 2012/// DO - 10.1021/bk-2012-1107.ch015 VL - 1107 SP - 271-296 ER - TY - JOUR TI - Three-Dimensional Structural Characterization of Nonwoven Fabrics AU - Venu, Lalith B. Suragani AU - Shim, Eunkyoung AU - Anantharamaiah, Nagendra AU - Pourdeyhimi, Behnam T2 - MICROSCOPY AND MICROANALYSIS AB - Nonwoven materials are found in a gamut of critical applications. This is partly due to the fact that these structures can be produced at high speed and engineered to deliver unique functionality at low cost. The behavior of these materials is highly dependent on alignment of fibers within the structure. The ability to characterize and also to control the structure is important, but very challenging due to the complex nature of the structures. Thus, to date, focus has been placed mainly on two-dimensional analysis techniques for describing the behavior of nonwovens. This article demonstrates the utility of three-dimensional (3D) digital volumetric imaging technique for visualizing and characterizing a complex 3D class of nonwoven structures produced by hydroentanglement. DA - 2012/12// PY - 2012/12// DO - 10.1017/s143192761201375x VL - 18 IS - 6 SP - 1368-1379 SN - 1435-8115 KW - fibrous structures KW - three-dimensional (3D) visualization KW - nonwovens KW - hydroentangling KW - fiber orientation KW - solid volume fraction ER - TY - JOUR TI - The effect of texture on perception and measurement of whiteness AU - Lin, J. AU - Shamey, R. AU - Trussell, J. T2 - AATCC Review DA - 2012/// PY - 2012/// VL - 12 IS - 2 SP - 61-68 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84858960808&partnerID=MN8TOARS ER - TY - JOUR TI - Temperature and Exposure Dependence of Hybrid Organic-Inorganic Layer Formation by Sequential Vapor Infiltration into Polymer Fibers AU - Akyildiz, Halil I. AU - Padbury, Richard P. AU - Parsons, Gregory N. AU - Jur, Jesse S. T2 - LANGMUIR AB - The characteristic processing behavior for growth of a conformal nanoscale hybrid organic–inorganic modification to polyamide 6 (PA6) by sequential vapor infiltration (SVI) is demonstrated. The SVI process is a materials growth technique by which exposure of organometallic vapors to a polymeric material promotes the formation of a hybrid organic–inorganic modification at the near surface region of the polymer. This work investigates the SVI exposure temperature and cycling times of sequential exposures of trimethylaluminum (TMA) on PA6 fiber mats. The result of TMA exposure is the preferential subsurface organic–inorganic growth by diffusion into the polymer and reaction with the carbonyl in PA6. Mass gain, infrared spectroscopy, and transmission electron microscopy analysis indicate enhanced materials growth and uniformity at lower processing temperatures. The inverse relationship between mass gain and exposure temperature is explained by the formation of a hybrid layer that prevents the diffusion of TMA into the polymer to react with the PA6 upon subsequent exposure cycles. As few as 10 SVI exposure cycles are observed to saturate the growth, yielding a modified thickness of ∼75 nm and mass increase of ∼14 wt %. Removal of the inherent PA6 moisture content reduces the mass gain by ∼4 wt % at low temperature exposures. The ability to understand the characteristic growth process is critical for the development of the hybrid materials fabrication and modification techniques. DA - 2012/11/6/ PY - 2012/11/6/ DO - 10.1021/la302991c VL - 28 IS - 44 SP - 15697-15704 SN - 0743-7463 ER - TY - JOUR TI - Liquid chromatographic and mass spectrometric analysis of dyes for forensic purposes AU - Beck, K. R. AU - Hinks, D. AU - Crawford, A. AU - Weisner, N. T2 - AATCC Review DA - 2012/// PY - 2012/// VL - 12 IS - 1 SP - 60-65 ER - TY - JOUR TI - Effect of liquor to goods ratio variation on sorption of reactive dye recipe components on cellulose AU - Ozturk, M. AU - Dayioglu, H. AU - Shamey, R. T2 - AATCC Review DA - 2012/// PY - 2012/// VL - 12 IS - 1 SP - 48-53 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84855959107&partnerID=MN8TOARS ER - TY - JOUR TI - Cotton bleaching optimization using a butyrolactam-based cationic bleach activator AU - Xu, C. AU - Shamey, R. AU - Hinks, D. AU - El-Shafei, A. T2 - AATCC Review DA - 2012/// PY - 2012/// VL - 12 IS - 1 SP - 66-70 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84855978049&partnerID=MN8TOARS ER - TY - JOUR TI - An environmentally benign approach to cotton preparation: One-bath enzymatic desizing, scouring, and activated bleaching AU - Li, M. AU - Hinks, D. T2 - AATCC Review DA - 2012/// PY - 2012/// VL - 12 IS - 5 SP - 46-51 ER - TY - JOUR TI - Electrochemical Performance of Carbon Nanofibers Containing an Enhanced Dispersion of Silicon Nanoparticles for Lithium-Ion Batteries by Employing Surfactants AU - Li, Ying AU - Lin, Zhan AU - Xu, Guanjie AU - Yao, Yingfang AU - Zhang, Shu AU - Toprakci, Ozan AU - Alcoutlabi, Mataz AU - Zhang, Xiangwu T2 - ECS ELECTROCHEMISTRY LETTERS AB - Si/C composite nanofibers were prepared by electrospinning and carbonization. Two surfactants: cetyl trimethyl ammonium bromide (CTAB) and sodium dodecanoate (SD), were used to improve the dispersion of Si nanoparticles and the electrochemical performance. Results show that after 50 cycles, the discharge capacity of Si/C nanofibers does not have significant change after the addition of CTAB surfactant, however, the discharge capacity of Si/C nanofibers with SD surfactant is more than 20% higher than that without surfactant. It is demonstrated that employing SD surfactant is a simple and effective way to obtain Si/C nanofibers with large capacities and good cycling stability. DA - 2012/// PY - 2012/// DO - 10.1149/2.002202eel VL - 1 IS - 2 SP - A31-A33 SN - 2162-8734 UR - https://publons.com/publon/674390/ ER - TY - JOUR TI - Surface modifications of polypropylene with nonylphenol ethoxylates melt additives AU - Datla, V. AU - Shim, E. AU - Pourdeyhimi, B. T2 - POLYMER ENGINEERING AND SCIENCE AB - Abstract Nonylphenol ethoxylated (NPE) additives were melt blended in polypropylene (PP) films and characteristics of the modified films were investigated. It was found that melt blending of NPE additives improved hydrophilicity of PP films through additive surface segregation. Surface specific techniques, such as X‐ray photoelectron spectroscopy (XPS) and Time‐of‐Flight Secondary Ion Mass Spectrometry (ToF‐SIMS) were used to study surface compositions of samples modified with NPE additives at different aging time after extrusion. We found that surface enrichment of additives lead to hydrophilic surfaces. Hydrophilic chain length in NPE affected surface composition and hydrophilicity of NPE containing PP polymer. The effect of water immersion and aging were also reported. POLYM. ENG. SCI., 52:1920–1927, 2012. © 2012 Society of Plastics Engineers DA - 2012/9// PY - 2012/9// DO - 10.1002/pen.23153 VL - 52 IS - 9 SP - 1920-1927 SN - 1548-2634 ER - TY - JOUR TI - Stable anatase TiO2 coating on quartz fibers by atomic layer deposition for photoactive light-scattering in dye-sensitized solar cells AU - Kim, Do Han AU - Koo, Hyung-Jun AU - Jur, Jesse S. AU - Woodroof, Mariah AU - Kalanyan, Berc AU - Lee, Kyoungmi AU - Devine, Christina K. AU - Parsons, Gregory N. T2 - NANOSCALE AB - Quartz fibers provide a unique high surface-area substrate suitable for conformal coating using atomic layer deposition (ALD), and are compatible with high temperature annealing. This paper shows that the quartz fiber composition stabilizes ALD TiO(2) in the anatase phase through TiO(2)-SiO(2) interface formation, even after annealing at 1050 °C. When integrated into a dye-sensitized solar cell, the TiO(2)-coated quartz fiber mat improves light scattering performance. Results also confirm that annealing at high temperature is necessary for better photoactivity of ALD TiO(2), which highlights the significance of quartz fibers as a substrate. The ALD TiO(2) coating on quartz fibers also boosts dye adsorption and photocurrent response, pushing the overall efficiency of the dye-cells from 6.5 to 7.4%. The mechanisms for improved cell performance are confirmed using wavelength-dependent incident photon to current efficiency and diffuse light scattering results. The combination of ALD and thermal processing on quartz fibers may enable other device structures for energy conversion and catalytic reaction applications. DA - 2012/// PY - 2012/// DO - 10.1039/c2nr30939d VL - 4 IS - 15 SP - 4731-4738 SN - 2040-3372 ER - TY - JOUR TI - Restructuring polymers via nanoconfinement and subsequent release AU - Tonelli, Alan E. T2 - BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY AB - During the past several years my students and I have been utilizing certain small-molecule hosts to create nanostructured polymers. This is accomplished by first forming noncovalently bonded inclusion complexes (ICs) between these small-molecule hosts and guest polymers, followed by the careful removal of the host crystalline lattice to obtain a coalesced bulk polymer. We have repeatedly observed that such coalesced polymer samples behave distinctly from those produced from their solutions or melts. Coalesced amorphous homopolymers exhibit higher glass-transition temperatures, while crystallizable homopolymers coalesced from their ICs display higher melting and crystallization temperatures, and sometimes different crystalline polymorphs. When ICs are formed with block copolymers or with two or more different homopolymers, the resulting coalesced samples can exhibit intimate mixing between the copolymer blocks, or between entire homopolymer chains. Each of the distinct behaviors observed for polymers coalesced from their ICs is a consequence of the structural organization of the polymer-host-ICs. Polymer chains in host-IC crystals are confined to occupy narrow channels (diameter ~0.5-1.0 nm) formed by the small-molecule hosts around the included guest polymers during IC crystallization. This results in the separation and high extension of the included guest polymer chains, which leads, following the careful removal of the host molecule lattice, to unique behaviors for the bulk coalesced polymer samples. Apparently, substantial degrees of the extended and unentangled natures of the IC-included chains are retained upon coalescence. In this review we summarize the behaviors and uses of coalesced polymers, and attempt to draw conclusions on the relationship between their behavior and the organization/structures/conformations of the constituent polymer chains achieved upon coalescence from their ICs. DA - 2012/8/16/ PY - 2012/8/16/ DO - 10.3762/bjoc.8.151 VL - 8 SP - 1318-1332 SN - 1860-5397 KW - cyclodextrins KW - inclusion compounds KW - nanoconfinement KW - organization KW - polymers KW - properties KW - release KW - urea ER - TY - JOUR TI - Release Profiles of Tricalcium Phosphate Nanoparticles from Poly(L-lactic acid) Electrospun Scaffolds with Single Component, Core-Sheath, or Porous Fiber Morphologies: Effects on hASC Viability and Osteogenic Differentiation AU - Asli, Mahsa Mohiti AU - Pourdeyhimi, Behnam AU - Loboa, Elizabeth G. T2 - MACROMOLECULAR BIOSCIENCE AB - Abstract Functional PLA scaffolds are created with single component, core–sheath, or porous fiber morphology and doped with TCP nanoparticles to study the release profiles for use in bone tissue engineering applications. Pharmacokinetic analyses are performed for the three different nanofibrous structures after doping with TCP. Results indicate that single component and porous fiber scaffolds exhibit an initial‐burst release profile whereas core–sheath fibers show a steady release. All scaffolds are then seeded with human adipose‐derived stem cells (hASC), which remain viable and continue proliferation on all nanofibrous morphologies for up to 21 d. Osteogenic differentiation of hASC and cell‐mediated calcium accretion are largest on porous fibers. magnified image DA - 2012/7// PY - 2012/7// DO - 10.1002/mabi.201100470 VL - 12 IS - 7 SP - 893-900 SN - 1616-5195 KW - biomaterials KW - controlled release scaffolds KW - human adipose derived stem cells KW - nanoparticles KW - osteogenesis ER - TY - JOUR TI - High-capacity Li2Mn0.8Fe0.2SiO4/carbon composite nanofiber cathodes for lithium-ion batteries AU - Zhang, Shu AU - Li, Ying AU - Xu, Guanjie AU - Li, Shuli AU - Lu, Yao AU - Toprakci, Ozan AU - Zhang, Xiangwu T2 - JOURNAL OF POWER SOURCES AB - Li2MnSiO4 has been considered as a promising cathode material with an extremely high theoretically capacity of 332 mAh g−1. However, due to its low intrinsic conductivity and poor structural stability, only about half of the theoretical capacity has been realized in practice and the capacity decays rapidly during cycling. To realize the high capacity and improve the cycling performance, Li2Mn0.8Fe0.2SiO4/carbon composite nanofibers were prepared by the combination of iron doping and electrospinning. X-ray diffraction, scanning electron microscope, and transmission electronic microscope were applied to characterize the Li2Mn0.8Fe0.2SiO4/carbon nanofibers. It was found that Li2Mn0.8Fe0.2SiO4 nanoparticles were embedded into continuous carbon nanofiber matrices, which formed free-standing porous mats that could be used as binder-free cathodes. The iron doping improved the conductivity and purity of the active material, and the carbon nanofiber matrix facilitated ion transfer and charge diffusion. As a result, Li2Mn0.8Fe0.2SiO4/carbon nanofiber cathodes showed promising improvement on reversible capacity and cycling performance. DA - 2012/9/1/ PY - 2012/9/1/ DO - 10.1016/j.jpowsour.2012.04.011 VL - 213 SP - 10-15 SN - 1873-2755 UR - https://publons.com/publon/674394/ KW - Li2MnSiO4 KW - Iron doping KW - Cathode KW - Electrospinning KW - Carbon nanofibers ER - TY - JOUR TI - Hemp-fiber Based Nonwoven Composites: Effects of Alkalization on Sound Absorption Performance AU - Yilmaz, Nazire Deniz AU - Powell, Nancy B. AU - Banks-Lee, Pamela AU - Michielsen, Stephen T2 - FIBERS AND POLYMERS DA - 2012/9// PY - 2012/9// DO - 10.1007/s12221-012-0915-0 VL - 13 IS - 7 SP - 915-922 SN - 1875-0052 UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000309249900015&KeyUID=WOS:000309249900015 KW - Sound absorption KW - Alkalization KW - Nonwoven KW - Composite KW - Biodegradable ER - TY - JOUR TI - Direct coloration of textiles with photochromic dyes. Part 3: dyeing of wool with photochromic acid dyes AU - Billah, Shah M. Reduwan AU - Christie, Robert M. AU - Shamey, Renzo T2 - COLORATION TECHNOLOGY AB - Wool dyed with two isomeric water‐soluble spirooxazine‐based photochromic acid dyes, which were specifically designed and synthesised for direct application to protein and polyamide substrates, showed reversible change from a pale yellowish colour to blue when exposed to sunlight or UV light. With the first dye, significantly higher photochromic colour change was obtained when the wool was bleached, a feature attributed to a more open fibre structure which may facilitate penetration of the non‐planar dye anion and also the photocoloration reaction which requires a change in molecular geometry. Experimentation demonstrated that the optimum conditions for application of this dye to wool was from an aqueous dyebath at neutral pH and a temperature of 60 °C. An investigation using HPLC demonstrated that the dye was susceptible to decomposition in aqueous solution at higher temperatures and at lower pH values. The second dye was also applied to wool fabric to give a fabric with similar photochromic properties. The technical performance of the dyed fabrics, in terms of washfastness and photostability, was assessed. DA - 2012/12// PY - 2012/12// DO - 10.1111/j.1478-4408.2012.00406.x VL - 128 IS - 6 SP - 488-492 SN - 1478-4408 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84867441760&partnerID=MN8TOARS ER - TY - JOUR TI - Development of Active Porous Medium Filters Based on Plasma Textiles AU - Kuznetsov, Ivan A. AU - Saveliev, Alexei V. AU - Rasipuram, Srinivasan AU - Kuznetsov, Andrey V. AU - Brown, Alan AU - Jasper, Warren T2 - POROUS MEDIA AND ITS APPLICATIONS IN SCIENCE, ENGINEERING, AND INDUSTRY AB - Inexpensive, flexible, washable, and durable materials that serve as antimicrobial filters and self-decontaminating fabrics are needed to provide active protection to people in areas regularly exposed to various biohazards, such as hospitals and bio research labs working with pathogens. Airlines and cruise lines need such material to combat the spread of infections. In households these materials can be used in HVAC filters to fight indoor pollution, which is especially dangerous to people suffering from asthma. Efficient filtering materials are also required in areas contaminated by other types of hazardous dust particulates, such as nuclear dust. The primary idea that guided the undertaken study is that a microplasma-generating structure can be embedded in a textile fabric to generate a plasma sheath (“plasma shield”) that kills bacterial agents coming in contact with the fabric. The research resulted in the development of a plasma textile that can be used for producing new types of self-decontaminating garments, fabrics, and filter materials, capable of activating a plasma sheath that would filter, capture, and destroy any bacteriological agent deposited on its surface. This new material relies on the unique antimicrobial and catalytic properties of cold (room temperature) plasma that is benign to people and does not cause thermal damage to many polymer textiles, such as Nomex and polypropylene. The uniqueness of cold plasma as a disinfecting agent lies in the inability of bacteria to develop resistance to plasma exposure, as they can for antibiotics. Plasma textiles could thus be utilized for microbial destruction in active antimicrobial filters (for continuous decontamination and disinfection of large amounts of air) as well as in self-decontaminating surfaces and antibacterial barriers (for example, for creating local antiseptic or sterile environments around wounds and burns). DA - 2012/// PY - 2012/// DO - 10.1063/1.4711186 VL - 1453 SP - 265-270 SN - 0094-243X KW - Plasma textiles KW - bacteria deactivation KW - cold plasma KW - corona discharge ER - TY - JOUR TI - Determining the Regioregularity in Alkyne Polycarbodiimides and Their Orthogonal Modification of Side Chains To Yield Perfectly Alternating Functional Polymers AU - Budhathoki-Uprety, Januka AU - Reuther, James F. AU - Novak, Bruce M. T2 - MACROMOLECULES AB - To understand the structure–property relationship in functional macromolecules through side chain modulation, both the accurate determination of the position of modifiable groups along the polymer chain and their subsequent modifications using high fidelity methods are crucial. In this report, the polymer microstructure of a helical alkyne polycarbodiimide has directly been probed through 15N NMR spectroscopy on isotopic labeled poly(N-(3-ethynylphenyl)-15N′-hexyl)carbodiimide and found to be a highly regioregular polymer structure. This polymer undergoes facile and quantitative CuAAC “click” chemistry, yielding perfectly alternating functional polymers. Advances have been made through the synthesis of new optically active alkyne polycarbodiimides with two independently modifiable pendant groups per repeat unit of polymers. Orthogonal postmodifications of the pendant groups were then performed to incorporate two different sets of small molecules in the repeat unit of polymers in a controlled manner and under mild reaction conditions using either sequential CuAAC “click” reactions when two dissimilar alkyne groups are present or a combination of CuAAC and thiol–ene click chemistries when pendant groups bear alkyne and vinyl moieties. DA - 2012/10/23/ PY - 2012/10/23/ DO - 10.1021/ma301639m VL - 45 IS - 20 SP - 8155-8165 SN - 1520-5835 UR - http://dx.doi.org/10.1021/ma301639m ER - TY - JOUR TI - Dependence of the liquid absorption behavior of nonwovens on their material and structural characteristics: Modeling and experiments AU - Das, Dipayan AU - Pradhan, Arun Kumar AU - Pourdeyhimi, Behnam T2 - JOURNAL OF APPLIED POLYMER SCIENCE AB - Abstract Nonwovens are widely used as liquid absorbent products. Baby diapers, sanitary napkins, adult incontinence pads, oil sorbents, wet wipes, and wound dressings, to name a few, are excellent examples of the use of nonwovens as absorbent media. The performance of nonwoven absorbent media is determined by its liquid absorption behavior, which is characterized by the capacity of absorption and the rate of absorption. In this article, we report on the effects of the physical characteristics of the constituent fibers and the internal structure of the nonwovens on their liquid absorption behavior. A theoretical model of liquid absorption behavior of nonwovens was developed, and this model was verified with a set of experimental results obtained on real nonwoven materials. The nonwoven materials were prepared with polyester fibers with different cross‐sectional sizes and their liquid absorption properties were measured with the gravimetric absorbency testing system. We observed that the size of fiber cross sections and the porosity of the nonwovens played very important roles in determining their absorbent capacity and rate of absorption. The results of the experiments were discussed in light of the theoretical model. The theoretical results were found to be in good agreement with the experimental results. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 DA - 2012/11/5/ PY - 2012/11/5/ DO - 10.1002/app.36635 VL - 126 IS - 3 SP - 1053-1060 SN - 1097-4628 KW - absorption KW - fibers KW - modeling KW - nonwoven KW - structure ER - TY - JOUR TI - Assessing the validity of a niche strategy model in predicting the potential and success of niche markets and products AU - Allen, Reece AU - Parrish, Erin AU - Cassill, Nancy L. AU - Oxenham, William T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - Companies can increase market share and profitability through the use of a niche market strategy. Parrish examined how companies use a niche market strategy and developed the Parrish Niche Strategy Model. This paper presents results of a study testing the model in terms of: (1) predicting the potential of a niche market and/or product and (2) predicting the success of a niche market and/or product. In order to test the model, deductive logic was used to develop questions that would gather quantitative data related to market potential strategies and success variables. In order to determine the importance of variables in relation to predicting the potential and success of a niche market and/or product, instrument questions were developed that utilized rank order scales. In addition, three-point Likert scales were used in order to determine the level of importance for each of the market potential and success variables. The sample consisted of fiber and yarn manufacturers, fabric manufacturers, apparel manufacturers and marketers, and retailers. Results indicate that the Parrish Niche Strategy Model was useful for gaging the potential and success of niche strategies, in terms of both product and market. This research was significant in that it tested the only existing model of niche strategies developed specifically for the textile industry. In addition, this study focused on bottomweights, which represents a significant domestic consumption market for the US textile supply chain. DA - 2012/// PY - 2012/// DO - 10.1080/00405000.2011.627156 VL - 103 IS - 8 SP - 900-911 SN - 0040-5000 KW - niche marketing KW - Parrish Niche Strategy Model KW - bottomweights ER - TY - JOUR TI - Templating Quantum Dot to Phase-Transformed Electrospun TiO2 Nanofibers for Enhanced Photo-Excited Electron Injection AU - Aykut, Yakup AU - Saquing, Carl D. AU - Pourdeyhimi, Behnam AU - Parsons, Gregory N. AU - Khan, Saad A. T2 - ACS APPLIED MATERIALS & INTERFACES AB - We report on the microstructural crystal phase transformation of electrospun TiO2 nanofibers generated via sol–gel electrospinning technique, and the incorporation of as-synthesized CdSe quantum dots (QDs) to different phases of TiO2 nanofibers (NFs) via bifunctional surface modification. The effect of different phases of TiO2 on photo-excited electron injection from CdSe QDs to TiO2 NFs, as measured by photoluminescence spectroscopy (PL) is also discussed. Nanofiber diameter and crystal structures are dramatically affected by different calcination temperatures due to removal of polymer carrier, conversion of ceramic precursor into ceramic nanofibers, and formation of different TiO2 phases in the fibers. At a low calcination temperature of 400 oC only anatase TiO2 nanofiber are obtained; with increasing calcination temperature (up to 500 oC) these anatase crystals became larger. Crystal transformation from the anatase to the rutile phase is observed above 500oC, with most of the crystals transforming into the rutile phase at 800oC. Bi-functional surface modification of calcined TiO2 nanofibers with 3-mercaptopropionic acid (3-MPA) is used to incorporate as-synthesized CdSe QD nanoparticles on to TiO2 nanofibers. Evidence of formation of CdSe/TiO2 composite nanofibers is obtained from elemental analysis using Energy Dispersive X-ray spectroscopy (EDS) and TEM microscopy that reveal templated quantum dots on TiO2 nanofibers. Photoluminescence emission intensities increase considerably with the addition of QDs to all TiO2 nanofiber samples, with fibers containing small amount of rutile crystals with anatase crystals showing the most enhanced effect. DA - 2012/8// PY - 2012/8// DO - 10.1021/am300524a VL - 4 IS - 8 SP - 3837-3845 SN - 1944-8252 KW - quantum dot KW - sol-gel electrospinning KW - nanofibers KW - photoluminescence ER - TY - JOUR TI - Sustainable Cotton Dyeing AU - Hauser, Peter J. T2 - ECO-DYEING, FINISHING AND GREEN CHEMISTRY AB - Conventional methods of dyeing cotton with direct and fiber reactive dyes involve large amounts of water and salt and generate significant amounts of highly colored effluent that is difficult to treat in waste water treatment facilities. Cationization of cotton with 3-chloro-2-hydroxypropyltrimethylammonium chloride allows dyeing with direct and fiber reactive dyes with less water and energy usage as well as the eliminating the need for salt. This paper summarizes work to date on the benefits of using cationized cotton. DA - 2012/// PY - 2012/// DO - 10.4028/www.scientific.net/amr.441.1 VL - 441 SP - 1-4 SN - 1022-6680 KW - Cationized cotton KW - Direct dyes KW - Fiber reactive dyes KW - Sustainable cotton dyeing KW - 3-chloro-2-hydroxypropyltrimethylammonium chloride ER - TY - JOUR TI - Structure-photovoltaic performance relationships for DSSC sensitizers having heterocyclic and benzene spacers AU - Kim, Bo Hyung AU - Freeman, Harold S. T2 - JOURNAL OF MATERIALS CHEMISTRY AB - Five new sensitizers based on different spacer groups were designed and synthesized in order to facilitate investigation of the effects of heterocyclic spacers on photovoltaic parameters in DSSCs. It was found that generic issues arising from the electronic nature of heterocyclic units affected voltage parameters, with DP-P giving the highest voltage. On the other hand, higher electron transfer yield across a wide range of the solar spectrum played an important role in enhanced current densities. Best performance was achieved by the thiophene based sensitizer DP-T, resulting in an efficiency of 3.5% with Jsc = 8.19 mA cm−2, Voc = 0.618 V, ff = 0.697. DA - 2012/// PY - 2012/// DO - 10.1039/c2jm33228k VL - 22 IS - 38 SP - 20403-20409 SN - 1364-5501 ER - TY - JOUR TI - Numerical modelling of damage initiation in low-density thermally bonded nonwovens AU - Farukh, Farukh AU - Demirci, Emrah AU - Sabuncuoglu, Baris AU - Acar, Memis AU - Pourdeyhimi, Behnam AU - Silberschmidt, Vadim V. T2 - COMPUTATIONAL MATERIALS SCIENCE AB - Due to random orientation of fibres and presence of voids in their microstructure, low-density thermally bonded polymer-based nonwovens demonstrate complex processes of deformation and damage initiation and evolution. This paper aims to introduce a micro-scale discontinuous finite element model to simulate an onset of damage in low-density nonwovens. In the model, structural randomness of a nonwoven fabric was introduced in terms of orientation distribution function (ODF) obtained by an algorithm based on the Hough Transform. Fibres were represented in the model with truss elements with orientations defined according to the computed ODF. Another structural element of nonwovens – bond points – were modelled with shell elements having isotropic mechanical properties. The numerical scheme employed direct modelling of fibres at micro level, naturally introducing the presence of voids into the model and thus making it suitable for simulations of low-density nonwovens. The obtained results of FE simulations were compared with our data of tensile tests performed in principal directions until the onset of damage in the specimens. DA - 2012/11// PY - 2012/11// DO - 10.1016/j.commatsci.2012.05.038 VL - 64 SP - 112-115 SN - 1879-0801 KW - Nonwoven KW - Anisotropy KW - Finite element KW - Damage ER - TY - JOUR TI - Modeling of Cross-Flow Across an Electrostatically Charged Monolith Filter AU - Gangadharan, S. AU - Kuznetsov, A. V. AU - Zhu, H. AU - Hinestroza, J. AU - Jasper, W. J. T2 - PARTICULATE SCIENCE AND TECHNOLOGY AB - The flow field and filtration efficiency of electrostatically charged micro-channel filters under cross-flow conditions were modeled. In our simulations, the fluid flows tangentially to the filter face (cross-flow). Particles with diameters larger than 2 μm were considered in this study, hence, the effects of Brownian motion were not included in the simulations. The influence of particle size, pressure drop, and electrostatic charge on the filtration efficiency was investigated. Measurements from performing electrostatic force microscopy (EFM) on the monolith sample confirmed the presence of charge and gave a qualitative measurement of the charge distribution. Results from the flow simulations indicate that the electrostatic forces increased the particle capture efficiency only at lower pressure drop. At higher pressure drops, electrostatic forces did not significantly increase the capture efficiency of the particles. Also, the capture efficiency of relatively small particles is found to be more dependent on the pressure drop across the filter than that of larger particles. DA - 2012/// PY - 2012/// DO - 10.1080/02726351.2011.604394 VL - 30 IS - 5 SP - 461-473 SN - 0272-6351 KW - cross-flow KW - filtration efficiency KW - monolith filter ER - TY - JOUR TI - Factors affecting the whiteness of optically brightened material AU - Lin, Juan AU - Shamey, Renzo AU - Hinks, David T2 - JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION AB - The whiteness of fluorescent white materials is in part due to the absorption of ultraviolet (UV) light and subsequent emission of visible blue light. The UV content of light sources in viewing booths and in spectrophotometers can thus significantly affect the perceived whiteness (PW) and measured sum of reflected and emitted light of fluorescent materials. The effect of UV content on the spectral radiance factor of fluorescent white materials containing different amounts of a fluorescent brightening agent and the subsequent assessment of their PW were evaluated. The UV content of sources in two calibrated viewing booths that simulated D65 and D75 illuminants, separately, was changed by selectively blocking UV emission of the source by approximately 0%, 25%, 50%, 75%, and 100%. The radiance spectra of a series of white fabrics were also obtained using a reflectance spectrophotometer at 0%, 25%, 50%, 75%, and 100% UV transmittance. The CIE and Uchida whiteness indices (WIs) were calculated for white samples and compared to perceptual results under varying illumination and UV conditions. Results indicate relatively modest agreement between perceptual assessments of fluorescent samples and whiteness metrics examined. Results also show that when the UV content of sources used in the viewing booths is adjusted to be similar to that used in measurements, improved correlations between perceptual and calculated results are obtained. The CIE WI was found to outperform the Uchida index under both sources. DA - 2012/11// PY - 2012/11// DO - 10.1364/josaa.29.002289 VL - 29 IS - 11 SP - 2289-2299 SN - 1520-8532 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84869782509&partnerID=MN8TOARS ER - TY - JOUR TI - Effect of Solution Parameters on Spontaneous Jet Formation and Throughput in Edge Electrospinning from a Fluid-Filled Bowl AU - Thoppey, Nagarajan M. AU - Gorga, Russell E. AU - Bochinski, Jason R. AU - Clarke, Laura I. T2 - MACROMOLECULES AB - The process of edge electrospinning relies on forming electric-field-induced instabilities (i.e., jets) in a polymer solution bath which act as sources for nanofiber production. As such, it depends on the fundamental interactions between the fluid and the electric field, which are studied in this report as a function of solution parameters (viscosity, surface tension, and conductivity). Over a wide range of conditions, experimental observations including time required for initial jet formation, total number of jets, feed rate per jet, and resultant fiber diameter are reported and compared with theoretical predictions. The presently realized fiber throughput is 40× a single needle approach while maintaining similar high fiber quality. Two distinct voltage intervals are utilized to generate many fiber-forming instabilities: a high level for jet creation and then reduced amplitude for fiber production. This dual-stage approach relies on hysteresis in Taylor cone-jet formation, wherein a larger voltage is required to create a jet-emitting cone than to maintain it. DA - 2012/8/28/ PY - 2012/8/28/ DO - 10.1021/ma301207t VL - 45 IS - 16 SP - 6527-6537 SN - 1520-5835 ER - TY - JOUR TI - Designing Energy-Storage Devices from Textile Materials AU - Zhang, Xiangwu AU - Ji, Liwen AU - Lin, Zhan AU - Li, Ying AU - Shao, JH AU - Fan, QG T2 - ECO-DYEING, FINISHING AND GREEN CHEMISTRY AB - Research and development in textiles have gone beyond the conventional applications as clothing and furnishing materials; for example, the convergence of textiles, nanotechnologies, and energy science opens up the opportunity to take on one of the major challenges in the 21st century energy. This presentation addresses the development of high-energy lithium-ion batteries using electrospun nanofibers. DA - 2012/// PY - 2012/// DO - 10.4028/www.scientific.net/amr.441.231 VL - 441 SP - 231-234 SN - 1022-6680 UR - https://publons.com/publon/6540103/ KW - Fibers KW - Electrospinning KW - Energy Storage KW - Lithium-Ion Battery ER - TY - JOUR TI - Cardiac tissue development for delivery of embryonic stem cell-derived endothelial and cardiac cells in natural matrices AU - Turner, William S. AU - Wang, Xiaoling AU - Johnson, Scott AU - Medberry, Christopher AU - Mendez, Jose AU - Badylak, Stephen F. AU - McCord, Marian G. AU - McCloskey, Kara E. T2 - JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS AB - Abstract The packaging and delivery of cells for cardiac regeneration has been explored using a variety biomaterials and delivery methods, but these studies often ignore one or more important design factors critical for rebuilding cardiac tissue. These include the biomaterial architecture, strength and stiffness, cell alignment, and/or incorporation of multiple cell types. In this article, we explore the combinatorial use of decellularized tissues, moldable hydrogels, patterned cell‐seeding, and cell‐sheet engineering and find that a combination of these methods is optimal in the recreation of transplantable cardiac‐like tissue in vivo . We show that decellularized urinary bladder matrix (UBM), that is compliant and suturable, supports the survival of cell cultures but does not allow maintenance of cell‐to‐cell contacts of transferred cell‐sheets (presumably, due to its rough surface). Moreover, the UBM material must be filled with hyaluronan (HA) hydrogels for smoothing rough surfaces and allowing the delivery of greater cell numbers. We additionally incorporated our previously developed “wrinkled” microchip for inducing alignment of cardiac cells with a laser‐etched mask for co‐seeding patterned “channels” of cells. This article also introduces a novel method of plasma coating for cell‐sheet engineering that compares well with electron bean irradiation methods and may be combined with our “wrinkled” surfaces to facilitate the alignment of cardiac cells into sheets. Our data shows that an optimal design for generating cardiac tissue would include (1) decellularized matrix seeded with endothelial cells in a HA layered with (2) prealigned cardiac cell‐sheets fabricated using our “wrinkled” microchips and thermo‐responsive polymer [poly( N ‐isopropylacrylamide)] cell sheet transfer system. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012. DA - 2012/11// PY - 2012/11// DO - 10.1002/jbm.b.32770 VL - 100B IS - 8 SP - 2060-2072 SN - 1552-4981 KW - cell delivery KW - decellularized tissues KW - urinary bladder matrix KW - cardiac tissue KW - hyaluronan hydrogel KW - cell sheet engineering KW - embryonic stem cells ER - TY - JOUR TI - Towards flame retardant cotton fabrics by atmospheric pressure plasma-induced graft polymerization: Synthesis and application of novel phosphoramidate monomers AU - Edwards, Brian AU - El-Shafei, Ahmed AU - Hauser, Peter AU - Malshe, Priya T2 - SURFACE & COATINGS TECHNOLOGY AB - The synthesis of two novel phosphoramidate flame retardant monomers for application to cotton textiles using atmospheric pressure dielectric barrier discharge (DBD) plasma was achieved and the molecular structures were characterized using +ESI-MS and FT-IR. The effects of plasma exposure time, monomer concentration, crosslinker chemistry, crosslinker concentration and photoinitiator concentration on grafting yield were investigated and the process was optimized for highest grafting yield. SEM images of the treated fabrics showed a grafted polymer layer covalently bonded to the polymer structure of cotton that survived a lengthy extraction process to remove ungrafted homopolymer and/or unreacted monomer. Thermogravimetric analysis showed that fabrics treated with the monomers demonstrated an increased thermal stability relative to untreated cotton. Vertical burn testing demonstrated the effectiveness of the grafted phosphorus-containing polymer at promoting char formation even though the fabrics were not self-extinguishing. Measurement of the amount of phosphorus present on the treated samples confirmed that the add-on using this application strategy was too low for self-extinguishing properties, but the rest of the evidence suggested that these compounds have the potential for use in generating flame retardant cotton substrates provided that a more suitable application strategy is developed to further improve grafting yield. DA - 2012/9/25/ PY - 2012/9/25/ DO - 10.1016/j.surfcoat.2012.08.031 VL - 209 SP - 73-79 SN - 0257-8972 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84866846185&partnerID=MN8TOARS KW - Flame retardant KW - Atmospheric pressure alasma KW - Graft polymerization ER - TY - JOUR TI - LiF/Fe/C nanofibres as a high-capacity cathode material for Li-ion batteries AU - Zhang, Shu AU - Lu, Yao AU - Xu, Guanjie AU - Li, Ying AU - Zhang, Xiangwu T2 - JOURNAL OF PHYSICS D-APPLIED PHYSICS AB - Abstract LiF/Fe/C composite nanofibres with different morphologies were prepared by electrospinning and heat treatment of LiF/ferrocene/polyacrylonitrile (PAN) precursors. X-ray diffraction and scanning electron microscopy were employed to study the structural variations of these composite nanofibres. It was found that Fe nanoparticles and carbon nanofibres were obtained from the thermal decomposition of ferrocene and PAN precursors, respectively. The electrochemical performance was evaluated using the prepared composite nanofibres as the cathode material in lithium half-cells. With uniformly embedded active particles in the carbon nanofibre matrix, the resultant cathode materials presented highly reversible discharge capacities of over 472 mA h g −1 . DA - 2012/10/3/ PY - 2012/10/3/ DO - 10.1088/0022-3727/45/39/395301 VL - 45 IS - 39 SP - SN - 1361-6463 UR - https://publons.com/publon/7178351/ ER - TY - JOUR TI - Development of electrospun iminochitosan for improved wound healing application AU - Nawalakhe, R. G. AU - Hudson, S. M. AU - Seyam, A. F. M. AU - Waly, A. I. AU - Abou-Zeid, N. Y. AU - Ibrahim, H. M. T2 - Journal of Engineered Fibers and Fabrics DA - 2012/// PY - 2012/// VL - 7 IS - 2 SP - 47-55 ER - TY - JOUR TI - Time-of-Flight-Secondary Ion Mass Spectrometry Method Development for High-Sensitivity Analysis of Acid Dyes in Nylon Fibers AU - Zhou, Chuanzhen AU - Li, Min AU - Garcia, Roberto AU - Crawford, Anne AU - Beck, Keith AU - Hinks, David AU - Griffis, Dieter P. T2 - ANALYTICAL CHEMISTRY AB - A minimally destructive technique for the determination of dyes in finished fibers provides an important tool for crime scene and other forensic investigations. The analytical power and the minimal sample consumption of time-of-flight-secondary ion mass spectrometric (TOF-SIMS) analysis provides the ability to obtain definitive molecular and elemental information relevant to fiber identification, including identification of dyes, from a very small volume of sample. For both fiber surface analysis and, with the aid of cryomicrotomy, fiber cross-section analysis, TOF-SIMS was used to identify various dyes in finished textile fibers. The analysis of C.I. Acid Blue 25 in nylon is presented as a representative example. The molecular ion of C.I. Acid Blue 25 with lower than 3% on weight-of-fiber (owf) dye loading cannot be identified on dyed nylon surfaces by TOF-SIMS using a Bi3+ primary ion beam. Sputtering with C60+ provided the ability to remove surface contamination as well as at least partially remove Bi-induced damage, resulting in a greatly improved signal-to-noise ratio for the Acid Blue 25 molecular ion. The use of C60+ for damage removal in a cyclic manner along with Bi for data acquisition provided the ability to unambiguously identify Acid Blue 25 via its molecular ion at a concentration of 0.1% owf from both fiber surfaces and cross sections. DA - 2012/11/20/ PY - 2012/11/20/ DO - 10.1021/ac3025569 VL - 84 IS - 22 SP - 10085-10090 SN - 1520-6882 ER - TY - JOUR TI - Structure-property relationship of naphthalene based donor-pi-acceptor organic dyes for dye-sensitized solar cells: remarkable improvement of open-circuit photovoltage AU - Yang, Fan AU - Akhtaruzzaman, Md. AU - Islam, Ashraful AU - Jin, Tienan AU - El-Shafei, Ahined AU - Qin, Chuanjiang AU - Han, Liyuan AU - Alamry, Khalid A. AU - Kosa, Samia A. AU - Hussein, Mahmoud A. AU - Asiri, Abdullah Mohamed AU - Yamamoto, Yoshinori T2 - JOURNAL OF MATERIALS CHEMISTRY AB - Four new donor–π–acceptor organic dyes (YF01–04), containing naphthalene-substituted amines as an electron donor and cyanoacrylic acid as an electron acceptor, were designed and synthesized, and their photophysical properties and dye-sensitized solar cells (DSCs) performances were characterized. Dyes YF02 and YF04, with 2,6-disubstituted naphthalene frameworks, were superior than their analog dyes YF03 and YF01, having 1,2-disubstituted naphthalene moiety, in incident-photo-to-current conversion efficiency (IPCE) and total solar-to-electric conversion efficiency (η). The DSCs based on YF02, comprised of diphenylamine moiety as the donor, produced the highest η of 5.29% compared to 4.03% of the analog dye YF04, which has pyrrolidine as the donor. Remarkably, a high open-circuit photovoltage (Voc) of 0.799–0.807 V was achieved in the cases of YF02–03, which have diphenylamine-donors. To better understand the structure–property relationship for DSCs application, molecular modelling was performed on YF01–04 and vertical electronic excitations were calculated using long-range corrected energy functional WB97XD and CAM-B3LYP at the basis set level DGDZVP, which were in excellent agreement with the experimental results. Moreover, the equilibrium molecular geometries of dyes YF01–04 were calculated at the density function theory (DFT) level using the hybrid energy functional B3LYP and basis set DGDZVP. The torsion angles (θ) between the naphthalene moiety and diphenylamine donor in YF02 and YF03 were more twisted than that of the pyrrolidine-donor dyes YF01 and YF04, precluding efficient intermolecular π–π charge transfer, which translated into high Voc. Compared to the reference dye TA-St-CA, which is based on diphenylamine as an electron donor linked to a phenyl ring, YF02 achieved higher Voc, which indicated that naphthalene substituted with diphenylamine is more efficient in retarding charge recombinations. DA - 2012/11/14/ PY - 2012/11/14/ DO - 10.1039/c2jm34363k VL - 22 IS - 42 SP - 22550-22557 SN - 0959-9428 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84867347533&partnerID=MN8TOARS ER - TY - JOUR TI - In Situ TEM Study of Lithiation Behavior of Silicon Nanoparticles Attached to and Embedded in a Carbon Matrix AU - Gu, Meng AU - Li, Ying AU - Li, Xiaolin AU - Hu, Shenyang AU - Zhang, Xiangwu AU - Xu, Wu AU - Thevuthasan, Suntharampillai AU - Baer, Donald R. AU - Zhang, Ji-Guang AU - Liu, Jun AU - Wang, Chongmin T2 - ACS NANO AB - Rational design of silicon and carbon nanocomposite with a special topological feature has been demonstrated to be a feasible way for mitigating the capacity fading associated with the large volume change of silicon anode in lithium ion batteries. Although the lithiation behavior of silicon and carbon as individual components has been well understood, lithium ion transport behavior across a network of silicon and carbon is still lacking. In this paper, we probe the lithiation behavior of silicon nanoparticles attached to and embedded in a carbon nanofiber using in situ TEM and continuum mechanical calculation. We found that aggregated silicon nanoparticles show contact flattening upon initial lithiation, which is characteristically analogous to the classic sintering of powder particles by a neck-growth mechanism. As compared with the surface-attached silicon particles, particles embedded in the carbon matrix show delayed lithiation. Depending on the strength of the carbon matrix, lithiation of the embedded silicon nanoparticles can lead to the fracture of the carbon fiber. These observations provide insights on lithium ion transport in the network-structured composite of silicon and carbon and ultimately provide fundamental guidance for mitigating the failure of batteries due to the large volume change of silicon anodes. DA - 2012/9// PY - 2012/9// DO - 10.1021/nn303312m VL - 6 IS - 9 SP - 8439-8447 SN - 1936-086X UR - https://publons.com/publon/7178349/ KW - Si nanoparticle KW - carbon fiber KW - Li-ion battery KW - in situ TEM KW - lithiation KW - fracture ER - TY - JOUR TI - Enhanced field electron emission from electrospun co-loaded activated porous carbon nanofibers AU - Aykut, Y. T2 - ACS Applied Materials & Interfaces DA - 2012/// PY - 2012/// VL - 4 IS - 7 SP - 3405-3415 ER - TY - JOUR TI - Cellulosic substrates for removal of pollutants from aqueous systems: A review. 2. dyes AU - Hubbe, M. A. AU - Beck, K. R. AU - O'Neal, W. G. AU - Sharma, Y. C. T2 - BioResources AB - Dyes used in the coloration of textiles, paper, and other products are highly visible, sometimes toxic, and sometimes resistant to biological breakdown; thus it is important to minimize their release into aqueous environments. This review article considers how biosorption of dyes onto cellulose-related materials has the potential to address such concerns. Numerous publications have described how a variety of biomass-derived substrates can be used to absorb different classes of dyestuff from dilute aqueous solutions. Progress also has been achieved in understanding the thermodynamics, kinetics, and chemical factors that control the uptake of dyes. Important questions remain to be more fully investigated, such as those involving the full life-cycle of cellulosic substrates that are used for the collection of dyes. Also, more work needs to be done in order to establish whether biosorption should be implemented as a separate unit operation, or whether it ought to be integrated with other water treatment technologies, including the enzymatic breakdown of chromophores. DA - 2012/// PY - 2012/// DO - 10.15376/biores.7.2.2592-2687 VL - 7 IS - 2 SP - 2592- ER - TY - JOUR TI - Prestrain-Free Dielectric Elastomers Based on Acrylic Thermoplastic Elastomer Gels: A Morphological and (Electro)Mechanical Property Study AU - Vargantwar, Pruthesh H. AU - Oezcam, A. Evren AU - Ghosh, Tushar K. AU - Spontak, Richard J. T2 - ADVANCED FUNCTIONAL MATERIALS AB - Abstract Recent efforts have established that thermoplastic elastomer gels (TPEGs) composed of styrenic triblock copolymers swollen with a midblock‐selective solvent exhibit remarkable electromechanical properties as high‐performance dielectric elastomers. This class of electroactive polymers typically requires high electric fields for actuation, and a shortcoming that continues to thwart the widespread commercialization of such materials in general is the need to apply mechanical prestrain prior to electroactuation to decrease film thickness and, thus, the electric potential required to promote actuation. To alleviate this requirement, TPEGs consisting of acrylic triblock copolymers differing in molecular weight and composition, and swollen with a high dielectric, midblock‐selective solvent are investigated. Synchrotron small‐angle x‐ray scattering is used to probe the nanoscale morphologies of the resultant materials, and analysis of quasi‐static and cyclic tensile properties provides additional insight into both blend morphologies and electroactuation efficacy. Actuation strains measured in the absence of mechanical prestrain exceed 100% on an area basis, and electric fields capable of inducing actuation are as low as ∼20 kV/mm. Failure occurs by either electromechanical instability or dielectric breakdown, depending on the copolymer and TPEG composition employed. The electromechanical properties of these acrylic‐based TPEGs match or exceed those of skeletal muscle, in which case they constitute an attractive and unexplored alternative to existing dielectric elastomers. DA - 2012/5/23/ PY - 2012/5/23/ DO - 10.1002/adfm.201101985 VL - 22 IS - 10 SP - 2100-2113 SN - 1616-301X ER - TY - JOUR TI - Plasma-Electrospinning Hybrid Process and Plasma Pretreatment to Improve Adhesive Properties of Nanofibers on Fabric Surface AU - Vitchuli, Narendiran AU - Shi, Quan AU - Nowak, Joshua AU - Nawalakhe, Rupesh AU - Sieber, Michael AU - Bourham, Mohamed AU - McCord, Marian AU - Zhang, Xiangwu T2 - PLASMA CHEMISTRY AND PLASMA PROCESSING DA - 2012/4// PY - 2012/4// DO - 10.1007/s11090-011-9341-0 VL - 32 IS - 2 SP - 275-291 SN - 1572-8986 UR - https://publons.com/publon/7178354/ KW - Adhesion KW - Plasma KW - Electrospinning KW - Surface KW - Nanofibers ER - TY - JOUR TI - Nanoscale ceramic surface modification of textiles by atomic layer deposition AU - Jur, J. S. AU - Parsons, G. N. T2 - American Ceramic Society Bulletin DA - 2012/// PY - 2012/// VL - 91 IS - 6 SP - 24-27 ER - TY - JOUR TI - LiFePO4 nanoparticles encapsulated in graphene-containing carbon nanofibers for use as energy storage materials AU - Toprakci, Ozan AU - Toprakci, Hatice A. K. AU - Ji, Liwen AU - Lin, Zhan AU - Gu, Renpeng AU - Zhang, Xiangwu T2 - JOURNAL OF RENEWABLE AND SUSTAINABLE ENERGY AB - LiFePO4/graphene/C composite nanofibers, in which LiFePO4 nanoparticles were encapsulated in graphene-containing carbon nanofiber matrix, were synthesized by using a combination of electrospinning and sol-gel techniques. Polyacrylonitrile (PAN) was used as the electrospinning media and the carbon source. Graphene was incorporated in order to increase the conductivity of the composite. PAN was dissolved in N,N–dimethylformamide (DMF). LiFePO4 precursor and graphene were dispersed in DMF separately and were mixed with PAN solution before electrospinning. Electrospun fibers were heat-treated to obtain LiFePO4/graphene/C composite nanofibers. The structure of LiFePO4/graphene/C composite nanofibers was determined by X–ray diffraction analysis. The surface morphology and microstructure of LiFePO4/graphene/C composite nanofibers were characterized using scanning electron microscopy and transmission electron microscopy. Electrochemical performance of LiFePO4/graphene/C composite nanofibers was evaluated in coin-type cells. Graphene flakes were found to be well-dispersed in the carbonaceous matrix and increased the electrochemical performance of the composite nanofibers. As a result, cells containing LiFePO4/graphene/C composite nanofiber cathodes showed good electrochemical performance, in terms of capacity, cycle life, and rate capability. DA - 2012/1/1/ PY - 2012/1/1/ DO - 10.1063/1.3690936 VL - 4 IS - 1 SP - SN - 1941-7012 UR - https://publons.com/publon/674392/ KW - crystal microstructure KW - electrical conductivity KW - electrochemistry KW - electrospinning KW - graphene KW - iron compounds KW - lithium compounds KW - nanocomposites KW - nanofabrication KW - nanofibres KW - nanoparticles KW - scanning electron microscopy KW - sol-gel processing KW - surface morphology KW - transmission electron microscopy KW - X-ray diffraction ER - TY - JOUR TI - Drop impacts on electrospun nanofiber membranes AU - Sahu, R. P. AU - Sinha-Ray, S. AU - Yarin, A. L. AU - Pourdeyhimi, B. T2 - SOFT MATTER AB - This work reports a systematic study of drop impacts of polar and non-polar liquids onto different electrospun nanofiber membranes (of 8–10 μm thickness and pore sizes of 3–6 μm) with an increasing degree of hydrophobicity. The liquids studied were water, FC 7500 (Fluorinert fluid) and hexane. The nanofibers used were electrospun from polyacrylonitrile (PAN), nylon 6/6, polycaprolactone (PCL) and Teflon. It was found that for any liquid/fiber pair there exists a threshold impact velocity (∼1.5 to 3 m s−1) above which water penetrates membranes irrespective of their hydrophobicity. The other liquids (FC 7500 and hexane) penetrate the membranes even more easily. The low surface tension liquid, FC 7500, left the rear side of sufficiently thin membranes as a millipede-like system of tiny jets protruding through a number of pores. For such a high surface tension liquid as water, jets immediately merged into a single bigger jet, which formed secondary spherical drops due to capillary instability. No mechanical damage to the nanofiber mats after liquid perforation was observed. A theoretical estimate of the critical membrane thickness sufficient for complete viscous dissipation of the kinetic energy of penetrating liquid is given and corroborated by the experimental data. DA - 2012/// PY - 2012/// DO - 10.1039/c2sm06744g VL - 8 IS - 14 SP - 3957-3970 SN - 1744-683X ER - TY - JOUR TI - Donor-acceptor dyes incorporating a stable dibenzosilole pi-conjugated spacer for dye-sensitized solar cells AU - Akhtaruzzaman, Md. AU - Seya, Yohei AU - Asao, Naoki AU - Islam, Ashraful AU - Kwon, Eunsang AU - El-Shafei, Ahmed AU - Han, Liyuan AU - Yamamoto, Yoshinori T2 - JOURNAL OF MATERIALS CHEMISTRY AB - Four novel organic dyes including three based on dibenzosilole (YS01–03) and one based on fluorene (YS04) were synthesized, and their photophysical properties and dye-sensitized solar cell (DSC) performances were characterized. The silicon-containing dibenzosilole-based dyes (YS01–03) were superior to the carbon analogue fluorene-based dye YS04 in incident-photon-to-current conversion efficiency (IPCE), and total solar-to-electric conversion efficiency (η), with YS03, which has the bulkiest and most branched electron donor group, achieving the highest η of 5.07% compared to 2.88% of YS04. To better understand how silicon influences the excited state oxidation potentials (S+/*) and absorption maxima (λmax), the equilibrium molecular geometries of dyes YS01–04 were calculated using density functional theory (DFT) utilizing B3LYP energy functional and DGDZVP basis set. It was shown that the torsion angles (θ1 and θ2) across the biphenyl linkages of dyes containing silicon (YS01–03) were less twisted than that of the silicon-free dye (YS04), which enhanced the π–π* overlap, and that translated into photocurrent enhancements in the silicon-containing dyes YS01–03. Moreover, the vertical electronic excitations and S+/* of dyes YS01–04 were studied using different long-range corrected time-dependent DFT methods, including CAM-B3LYP, LC-BLYP, WB97XD, and LC-wPBE at the basis set level DGDZVP. Excellent agreement between the calculated, using CAM-B3LYP/DGDZVP, and experimental results was found. DA - 2012/// PY - 2012/// DO - 10.1039/c2jm30978e VL - 22 IS - 21 SP - 10771-10778 SN - 0959-9428 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84862671049&partnerID=MN8TOARS ER - TY - JOUR TI - A compact dielectric elastomer tubular actuator for refreshable Braille displays AU - Chakraborti, P. AU - Toprakci, H. A. Karahan AU - Yang, P. AU - Di Spigna, N. AU - Franzon, P. AU - Ghosh, T. T2 - SENSORS AND ACTUATORS A-PHYSICAL AB - Electroactive polymer actuators stimulated by appropriate levels of electric field are particularly attractive for human-assist devices such as Braille. The development of a full page refreshable Braille display is very important for the integration of the visually impaired into the new era of communication. In this paper, development of a compact dielectric elastomer actuator suitable for Braille application is reported. The actuators are fabricated from commercially available silicone tubes. The tube has been rendered mechanically anisotropic through asymmetric levels of applied pretension in circumferential and axial directions in order to direct the actuation strain in the axial direction of the actuator. Key performance parameters, such as displacement, force, and response time of the actuator are investigated. The test results demonstrate the potential of the compact, lightweight, and low cost dielectric elastomer as actuators for a refreshable full page Braille display. DA - 2012/6// PY - 2012/6// DO - 10.1016/j.sna.2012.02.004 VL - 179 SP - 151-157 SN - 0924-4247 KW - Electroactive polymers KW - Dielectric elastomer actuator KW - Braille display actuators KW - Refreshable Braille display ER - TY - JOUR TI - Study on the blend irregularity in blended yarns AU - Lin, Qian AU - Oxenham, William AU - Yu, Chongwen T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - A new model is developed to evaluate the theoretical blend irregularity of a two‐component blended yarn. By introducing the variation of the number of fibers per cross‐section along the yarn, the obtained expression can offer insight into the cause of blend irregularity. Two experiments show that the results from the new model have essentially the same changing tendency as experimental values. The value of the blend irregularity of one component is shown to decrease with the increase of its proportion and the blend irregularity also decreases in the case of finer fibers. DA - 2012/// PY - 2012/// DO - 10.1080/00405000.2010.542014 VL - 103 IS - 1 SP - 28-33 SN - 0040-5000 KW - blend irregularity KW - two-component blended yarn KW - variation of number of fibers KW - yarn unevenness ER - TY - JOUR TI - Quantification of cesium surface contamination on silicon resulting from SIMS analysis AU - Penley, C. AU - Stevie, F. A. AU - Griffis, D. P. T2 - JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B AB - In order to improve the understanding of unintended cesium (Cs) contamination that occurs during SIMS depth profiling, Cs concentrations on sample surfaces were measured before analysis and at various distances from a depth profile crater after analysis. Cs concentrations in excess of 1 at. % were found directly adjacent to the depth profile analysis site. Cs was also detected at significant concentrations hundreds of micrometers from the depth profile measurement location. This Cs contamination can originate from a number of sources including Cs beam tails, Cs neutral beam, and secondary sputtering from instrument optics and other structures. Since the presence of cesium significantly affects the secondary ion yield of electronegative elements (e.g., phosphorus) in silicon, the unintended presence of cesium on the surface of a previously analyzed sample can strongly affect the reproducibility and accuracy of low dose electronegative element measurements, especially at the surface. DA - 2012/// PY - 2012/// DO - 10.1116/1.3698400 VL - 30 IS - 3 SP - SN - 2166-2746 ER - TY - JOUR TI - Novel yellow azo-anthraquinone dyes for polylactide fibres: effects of alkyl chain length AU - Lu, Lihua AU - He, Liang AU - Zhang, Shufen AU - Freeman, Harold S. T2 - COLORATION TECHNOLOGY AB - 1‐(4′‐Alkylaminosulphurylphenyl)‐3‐methyl‐5‐pyrazolonyl azo–anthraquinone dyes were prepared in four steps from 1‐aminoanthraquinone, as an approach to enhancing the exhaustion levels of disperse dyes on polylactide fibres. Their structures were confirmed from combustion analysis and mass spectrometry, infrared and proton nuclear magnetic resonance spectroscopy. Results from artificial intelligence‐based molecular modelling studies showed that increasing alkyl chain length gave an increase in LogP, molecular volume and aplanar shape. Their application to polylactide fibres led to both good per cent exhaustion values and good light fastness ratings. It was also found that the nature of the alkyl chains attached to the phenyl ring had little influence on dye colour, but clearly influenced per cent exhaustion and wash fastness. DA - 2012/4// PY - 2012/4// DO - 10.1111/j.1478-4408.2011.00354.x VL - 128 IS - 2 SP - 121-126 SN - 1472-3581 ER - TY - JOUR TI - Modification of beta-cyclodextrin with itaconic acid and application of the new derivative to cotton fabrics AU - Nazi, Malihe AU - Malek, Reza Mohammad Ali AU - Kotek, Richard T2 - CARBOHYDRATE POLYMERS AB - β-Cyclodextrin (β-CD) is capable of forming inclusion complexes but cannot form a direct covalent bond with textile materials; hence, some cyclodextrin derivatives have been synthesised with reactive groups to allow them to chemically bind to various substrates. In this study, β-CD was modified with itaconic acid containing carboxyl and vinyl groups because this bifunctional compound can be attached to β-CD via the esterification reaction and because its vinyl group can perform free-radical polymerisation. The synthesised cyclodextrin itaconate was characterised using elemental and thermal analyses, solubility testing and NMR, FTIR and Raman spectroscopy. In addition, the impact of the grafting of this vinyl monomer on the performance of cotton fabric was investigated. The presence of anchored CD nanoparticles on the surface of the fibres was demonstrated by using SEM and FTIR as well as the ability of the attached CDs to form inclusion complexes. DA - 2012/4/15/ PY - 2012/4/15/ DO - 10.1016/j.carbpol.2012.01.047 VL - 88 IS - 3 SP - 950-958 SN - 0144-8617 KW - beta-Cyclodextrin itaconate KW - Cotton fabrics KW - Esterification KW - Graft copolymerisation ER - TY - JOUR TI - Electrification of antistatic-treated polymeric surface AU - Liu, L. AU - Theyson, T. AU - Oxenham, W. AU - Seyam, A. M. T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - Nylon and polypropylene surfaces were treated with three different finishes (nonionic, cationic, and anionic) at four different solution concentrations (weight percentage of active finish to solution), 0.025%, 0.05%, 0.075%, and 0.1%. Contact electrification tests showed that charge accumulated on polypropylene decreased as the concentration of nonionic and anionic solutions increased, and charge could be controlled when the concentration reached 0.1%. The same effect was realized when the concentration of the cationic solution was only 0.025%. No contact charging was observed on nylon after treating with any solutions. Rubbing electrification (tribo‐charging) of nylon treated with the nonionic solution showed that charge decreased as the solution concentration increased, and no charge was observed as the solution concentration reached 0.1%. Furthermore, no tribo‐charging of nylon was observed at any level of the cationic or anionic agents applied to the surface. DA - 2012/// PY - 2012/// DO - 10.1080/00405000.2011.564798 VL - 103 IS - 2 SP - 215-224 SN - 0040-5000 KW - contact charging KW - tribo-charging KW - nonionic agent KW - cationic agent KW - anionic agent ER - TY - JOUR TI - Carbon Nanotube-Loaded Electrospun LiFePO4/Carbon Composite Nanofibers As Stable and Binder-Free Cathodes for Rechargeable Lithium-Ion Batteries AU - Toprakci, Ozan AU - Toprakci, Hatice A. K. AU - Ji, Liwen AU - Xu, Guanjie AU - Lin, Zhan AU - Zhang, Xiangwu T2 - ACS APPLIED MATERIALS & INTERFACES AB - LiFePO4/CNT/C composite nanofibers were synthesized by using a combination of electrospinning and sol–gel techniques. Polyacrylonitrile (PAN) was used as the electrospinning media and carbon source. Functionalized CNTs were used to increase the conductivity of the composite. LiFePO4 precursor materials, PAN and functionalized CNTs were dissolved or dispersed in N,N–dimethylformamide separately and they were mixed before electrospinning. LiFePO4 precursor/CNT/PAN composite nanofibers were then heat-treated to obtain LiFePO4/CNT/C composite nanofibers. Fourier transform infrared spectroscopy measurements were done to demonstrate the functionalization of CNTs. The structure of LiFePO4/CNT/C composite nanofibers was determined by X–ray diffraction analysis. The surface morphology and microstructure of LiFePO4/CNT/C composite nanofibers were characterized using scanning electron microscopy and transmission electron microscopy. Electrochemical performance of LiFePO4/CNT/C composite nanofibers was evaluated in coin-type cells. Functionalized CNTs were found to be well-dispersed in the carbonaceous matrix and increased the electrochemical performance of the composite nanofibers. As a result, cells using LiFePO4/CNT/C composite nanofibers have good performance, in terms of large capacity, extended cycle life, and good rate capability. DA - 2012/3// PY - 2012/3// DO - 10.1021/am201527r VL - 4 IS - 3 SP - 1273-1280 SN - 1944-8252 UR - https://publons.com/publon/674388/ KW - lithium-ion batteries KW - cathodes KW - LiFePO4 KW - carbon nanofibers KW - carbon nanotubes ER - TY - JOUR TI - A bilayer prototype woven vascular prosthesis with improved radial compliance AU - Chen, Ying AU - Ding, Xin AU - Li, Yuling AU - King, Martin W. AU - Gao, Jie AU - Zhao, Xueqian T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - To minimize radial compliance mismatch between native arteries and vascular prostheses over the entire blood pressure range, a biomimetic woven prosthesis sample with a bilayer wall has been developed. Poly(trimethylene terephthalate) (PTT) filaments were used as the circumferential yarns in the inner layer to increase the radial compliance of the inner wall, and poly(ethylene terephthalate) (PET) filaments formed the outer layer to provide a strong and more rigid external prosthesis wall. The two layers were joined together axially along the sample's length by a stitched weave. By means of a special weave design, the cross‐section of the tubular sample included a circumferentially crimped outer layer woven around the inner layer. This bilayer wall structure allowed only the inner layer of the sample to deform radially under small loads equivalent to low normal physiological (diastolic) blood pressures. As the load increased, the inner layer stretched until it came into contact with the outer layer. At higher (systolic) pressures, further loading caused both layers of the wall to deform together. As a result, the prosthesis showed high pressure‐induced compliance when the load was within the normal diastolic pressure range and lower compliance at higher systolic pressures. DA - 2012/// PY - 2012/// DO - 10.1080/00405000.2011.552956 VL - 103 IS - 1 SP - 106-111 SN - 0040-5000 KW - bilayer KW - vascular prosthesis KW - compliance KW - poly(trimethylene terephthalate) KW - polyester KW - poly(ethylene terephthalate) ER - TY - JOUR TI - Nonlinear modeling of equilibrium sorption of selected anionic adsorbates from aqueous solutions on cellulosic substrates: part 2: experimental validation AU - Xu, Changhai AU - Shamey, Renzo T2 - CELLULOSE DA - 2012/6// PY - 2012/6// DO - 10.1007/s10570-012-9676-6 VL - 19 IS - 3 SP - 627-633 SN - 0969-0239 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84860354724&partnerID=MN8TOARS KW - Thermodynamics of equilibrium sorption KW - Sorption isotherm KW - Anionic adsorbate KW - Cellulose KW - Internal accessible volume KW - Nonlinear modeling ER - TY - JOUR TI - Nonlinear modeling of equilibrium sorption of selected anionic adsorbates from aqueous solutions on cellulosic substrates. Part 1: model development AU - Xu, Changhai AU - Shamey, Renzo T2 - CELLULOSE DA - 2012/6// PY - 2012/6// DO - 10.1007/s10570-012-9675-7 VL - 19 IS - 3 SP - 615-625 SN - 0969-0239 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84860387974&partnerID=MN8TOARS KW - Nonlinear modeling and analysis KW - Equilibrium sorption KW - Sorption isotherm KW - Anionic adsorbate KW - Cellulose KW - Internal accessible volume ER - TY - JOUR TI - Durable hydrophobic cotton surfaces prepared using silica nanoparticles and multifunctional silanes AU - Roe, Barry AU - Kotek, Richard AU - Zhang, Xiangwu T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - Durable non-fluorine hydrophobic cotton surfaces were obtained by treating woven cotton fabrics using combinations of silica nanoparticles and multifunctional silanes. Both the hydrophobicity and durability of treated cotton surfaces were controlled by selectively adjusting the alkyl chain length of silane hydrophobes and the surface chemistry, surface area, and content of silica nanoparticles. It was found that with an increase in the alkyl chain length of the silane hydrophobes, the hydrophobicity of treated cotton surfaces increased: the maximum surface durability was obtained at an alkyl chain length of 12 carbon atoms. Hydrophilic silica nanoparticles significantly improved the hydrophobicity and durability of treated cotton surfaces, whereas the hydrophobic silica nanoparticles were found to reduce them. The surface area of the silica nanoparticles did not have a significant impact on the cotton fabric hydrophobicity, however, a larger silica surface area resulted in better durability. The highest hydrophobicity (a contact angle of 142°) and the best durability (a 95.7% recovery of contact angle after heavy-duty industrial laundering) were achieved when treating cotton surfaces with the silane tetramethoxysilane crosslink enhancer, silane n-dodecyltrimethoxysilane hydrophobe (alkyl chain length = 12 carbon atoms), and 0.2% hydrophilic silica nanoparticles with a diameter of 12 nm. DA - 2012/// PY - 2012/// DO - 10.1080/00405000.2011.580540 VL - 103 IS - 4 SP - 385-393 SN - 0040-5000 UR - https://publons.com/publon/7178356/ KW - cotton KW - silica nanoparticles KW - silane KW - surface treatment KW - hydrophobicity ER - TY - JOUR TI - Behavior of Poly(epsilon-caprolactone)s (PCLs) Coalesced from Their Stoichiometric Urea Inclusion Compounds and Their Use as Nucleants for Crystallizing PCL Melts: Dependence on PCL Molecular Weights AU - Gurarslan, Alper AU - Shen, Jialong AU - Tonelli, Alan E. T2 - MACROMOLECULES AB - We have formed noncovalent inclusion compounds (ICs) between guest poly(ε-caprolactone) (PCL) chains, with molecular weights ranging from ∼2000 to 80 000 g/mol, and host urea (U). Upon careful removal of the U host, each of the guest PCL chains were coalesced from their U-IC crystals to produce coalesced samples (c-PCLs). As previously observed for PCL and other polymer guests when coalesced from their ICs formed with host cyclodextrins (CDs), upon cooling from their melts, PCLs coalesced from their U-ICs also show enhanced abilities to crystallize, regardless of their molecular weight. Also consistent with polymer guests, including PCL, that were coalesced from their CD-ICs, c-PCLs obtained from their U-ICs retain their enhanced abilities to crystallize even after spending long times (weeks or more) in the melt. Because, unlike CD hosts, U does not thread over guest polymer chains in their ICs, we conclude that the enhanced ability of c-PCLs to crystallize from their melts upon removal of either host from their ICs is solely a consequence of their coalesced conformations/structures/morphologies, which are stable to prolonged melt-annealing. Furthermore, because c-PCLs with chain lengths well below and well above those corresponding to the entanglement molecular weight of PCL behave similarly, we conclude that their enhanced ability to crystallize from the melt is likely an exclusive consequence of the extended and unentangled arrangement of their coalesced chains. In addition, c-PCLs obtained from their U-ICs are observed to effectively act as self-nucleants, when added in small amounts to as-received PCLs, to produce nuc-PCLs, which like neat c-PCLs exhibit an enhanced ability to melt-crystallize. DA - 2012/3/27/ PY - 2012/3/27/ DO - 10.1021/ma300270g VL - 45 IS - 6 SP - 2835-2840 SN - 1520-5835 ER - TY - JOUR TI - Synthesis of Guanidinium Functionalized Polycarbodiimides and Their Antibacterial Activities AU - Budhathoki-Uprety, Januka AU - Peng, LingLing AU - Melander, Christian AU - Novak, Bruce M. T2 - ACS MACRO LETTERS AB - A family of guanidinium-side-chain functionalized polycarbodiimides has been synthesized by allowing an azido guanidinium salt to react with alkyne polycarbodiimides via the copper catalyzed [3 + 2] cycloaddition (Click) reaction. Poly-2(a-d) are cationic/amphiphilic polymers in which the global hydrophilic/hydrophobic balance has been tailored by local alteration of the length of alkyl side chain in the repeat unit of polymers prior to polymerization. The shorter alkyl chains yield water-soluble polymers, Poly-2c, -2d, and -2e. Antibacterial activities of these cationic polycarbodiimides have been investigated for Gram-positive and Gram-negative bacteria that include Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Acinetobacter baumannii. It was observed that the influence of hydrophobic-hydrophilic balance per repeat unit of these polymers have profound effects for both antimicrobial and hemolytic activities. In addition, these polycarbodiimide-guanidinium-triazole conjugates offered moderate to significant antibacterial activity and rapid interaction with red blood cells causing blood precipitation without significant hemolysis in case of Poly-2(b-e). This latter property has the potential to be exploited in the polymer coatings or wound protection. DA - 2012/3// PY - 2012/3// DO - 10.1021/mz200116k VL - 1 IS - 3 SP - 370-374 SN - 2161-1653 UR - http://dx.doi.org/10.1021/mz200116k ER - TY - JOUR TI - Relationship between tensile properties and ballistic performance of poly(ethylene naphthalate) woven and nonwoven fabrics AU - Afshari, Mehdi AU - Chen, Peng AU - Kotek, Richard T2 - JOURNAL OF APPLIED POLYMER SCIENCE AB - Abstract In this study, we investigated the effect of tensile properties of poly(ethylene naphthalate) (PEN) yarns on the ballistic performance of woven and nonwoven soft and composite armors. The results of ballistic tests of PEN armors were compared with Kevlar 49 armors as a reference. Based on these results, the Cunniff's equation was revised by removing the fiber elongation at break to predict the relationship between tensile properties and ballistic performances of PEN fibers. The calculations showed that by increasing tenacity of PEN fibers from 8.5 g/den (commercial product) to 12.5 g/den (strongest up to date PEN fibers produced by a novel melt spinning process discovered by our research group), the weight ratio of PEN to Kevlar 49 decreased from 1.8 to 1.35 with the same ballistic performance. Contrary to the results of the soft armors, composite armors made of high modulus PEN woven fabric showed a 17% lower ballistic resistance compared to the composite armor made of low modulus PEN woven fabric. The results of ballistic tests indicated that high tenacity PEN fibers produced in this research could have potential in soft and composite armors, and high velocity impact applications or improve performance of PEN in its current applications. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 DA - 2012/8/5/ PY - 2012/8/5/ DO - 10.1002/app.36442 VL - 125 IS - 3 SP - 2271-2280 SN - 1097-4628 KW - poly(ethylene naphthalate) KW - ballistic performance KW - woven fabric KW - nonwoven fabric KW - tensile properties ER - TY - JOUR TI - Polymers coalesced from their cyclodextrin inclusion complexes: What can they tell us about the morphology of melt-crystallized polymers? AU - Gurarslan, Alper AU - Joijode, Abhay S. AU - Tonelli, Alan E. T2 - JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS AB - Abstract Cyclodextrins (CDs) are cyclic polysaccharides with nano‐size, largely hydrophobic cavities, and exteriors covered with hydrophilic hydroxyl groups, making them water soluble. Threading and filling their cavities with polymer chains produces noncovalently bonded crystalline inclusion compounds (ICs). In this study, we formed fully covered, stoichiometric ICs between guest poly( L ‐lactic acid), poly(ε‐caprolactone), and nylon‐6 chains and host α‐CD. Coalesced samples of all three polymers were obtained after appropriately removing the stacked α‐CD host channels from their ICs. Distinct differential scanning calorimetriy (DSC) thermograms were observed for as‐received and coalesced samples, with the coalesced samples crystallizing faster at higher temperatures from their melts, and this distinction was maintained even after extensive, long‐time melt‐annealing (hours, days, and weeks). We believe this is due to the largely unentangled chains with extended conformations that are more densely packed in the initially coalesced samples. When small amounts (∼2 wt %) of the coalesced polymers are used as self‐nucleating agents for their as‐received samples, the resulting self‐nucleated samples show DSC thermograms similar to those of the neat coalesced polymers, including their long‐time stability to melt‐annealing. Coalesced polymers, whether neat or in samples they self‐nucleate, may conserve their organization in the melt (largely extended and unentangled chains) for long periods, because the process of entangling the many chains influenced by a single initially extended unentangled coalesced chain, after it randomly coils, is extremely sluggish. By contrast, in melt‐crystallized or solution‐cast samples, polymer chains generally become fully randomly coiled, interpenetrate, and entangle after being heated and held in their melts for comparatively much shorter times. For example, we have recently observed (DSC) that ultra high molecular weight, gel‐spun spectra polyethylene (PE) fibers ® did not conserve or retain any memory of their as‐spun and highly drawn semicrystalline morphology even after spending as little as 2 min in the melt. As a consequence of the comparison to the behavior of coalesced polymer melts, we believe that polyethylene chains in Spectra fibers ® must be at least intimately dispersed within their crystalline regions, and likely partially coiled and entangled in their noncrystalline regions, thereby facilitating their rapid transformation into a full entanglement network of randomly coiling chains in the melt. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 DA - 2012/6/15/ PY - 2012/6/15/ DO - 10.1002/polb.23074 VL - 50 IS - 12 SP - 813-823 SN - 0887-6266 KW - cyclodextrin KW - inclusion chemistry KW - morphology KW - solid-state structure KW - thermal stability ER - TY - JOUR TI - Poly(vinyl alcohol) reinforced with large-diameter carbon nanotubes via spray winding AU - Liu, Wei AU - Zhao, Haibo AU - Inoue, Yoku AU - Wang, Xin AU - Bradford, Philip D. AU - Kim, Hyungsup AU - Qiu, Yiping AU - Zhu, Yuntian T2 - COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING AB - For practical application of carbon nanotube (CNT)/polymer composites, it is critical to produce the composites at high speed and large scale. In this study, multi-walled carbon nanotubes (MWNTs) with large diameter (∼45 nm) and polyvinyl alcohol (PVA) were used to increase the processing speed of a recently developed spraying winding technique. The effect of the different winding speed and sprayed solution concentration to the performance of the composite films were investigated. The CNT/PVA composites exhibit tensile strength of up to 1 GPa, and modulus of up to 70 GPa, with a CNT weight fraction of 53%. In addition, an electrical conductivity of 747 S/cm was obtained for the CNT/PVA composites. The good mechanical and electrical properties are attributed to the uniform CNTs and PVA matrix integration and the high degree of tube alignment. DA - 2012/4// PY - 2012/4// DO - 10.1016/j.compositesa.2011.12.029 VL - 43 IS - 4 SP - 587-592 SN - 1878-5840 KW - Discontinuous reinforcement KW - Polymer-matrix composites (PMCs) KW - Mechanical properties KW - Electrical properties ER - TY - JOUR TI - Optimal data use in staple yarn manufacturing AU - Hamilton, B. J. AU - Oxenham, W. AU - Hodge, G. L. AU - Thoney, K. A. T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - The contemporary cotton spinning mill is home to modern machinery capable of generating a plethora of data. This data comes in the form of online data, which is real-time data created by the processing machinery, and offline data, which is created via laboratory testing of samples. This paper describes a study which applied statistical techniques to the two data sets. One came from an actual open-end spinning plant. The other was created in a laboratory environment. This analysis served to discover trends within this data sample and to determine the optimal data use for the cotton spinning industry. In addition, the paper presents a perspective into the current state of data management in the cotton spinning industry obtained by visiting an assortment of active spinning mills. DA - 2012/// PY - 2012/// DO - 10.1080/00405000.2011.588837 VL - 103 IS - 5 SP - 499-507 SN - 0040-5000 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84860203802&partnerID=MN8TOARS KW - product data management KW - yarn manufacturing ER - TY - JOUR TI - alpha-Fe2O3 Nanoparticle-Loaded Carbon Nanofibers as Stable and High-Capacity Anodes for Rechargeable Lithium-Ion Batteries AU - Ji, Liwen AU - Toprakci, Ozan AU - Alcoutlabi, Mataz AU - Yao, Yingfang AU - Li, Ying AU - Zhang, Shu AU - Guo, Bingkun AU - Lin, Zhan AU - Zhang, Xiangwu T2 - ACS APPLIED MATERIALS & INTERFACES AB - α-Fe(2)O(3) nanoparticle-loaded carbon nanofiber composites were fabricated via electrospinning FeCl(3)·6H(2)O salt-polyacrylonitrile precursors in N,N-dimethylformamide solvent and the subsequent carbonization in inert gas. Scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and elemental analysis were used to study the morphology and composition of α-Fe(2)O(3)-carbon nanofiber composites. It was indicated that α-Fe(2)O(3) nanoparticles with an average size of about 20 nm have a homogeneous dispersion along the carbon nanofiber surface. The resultant α-Fe(2)O(3)-carbon nanofiber composites were used directly as the anode material in rechargeable lithium half cells, and their electrochemical performance was evaluated. The results indicated that these α-Fe(2)O(3)-carbon nanofiber composites have high reversible capacity, good capacity retention, and acceptable rate capability when used as anode materials for rechargeable lithium-ion batteries. DA - 2012/5// PY - 2012/5// DO - 10.1021/am300333s VL - 4 IS - 5 SP - 2672-2679 SN - 1944-8244 UR - https://publons.com/publon/674393/ KW - lithium-ion batteries KW - anodes KW - nanofibers KW - carbon KW - alpha-Fe2O3 ER - TY - JOUR TI - Stress-strain dependence for soy-protein nanofiber mats AU - Khansari, S. AU - Sinha-Ray, S. AU - Yarin, A. L. AU - Pourdeyhimi, B. T2 - JOURNAL OF APPLIED PHYSICS AB - Soy protein/nylon 6 monolithic and core-shell nanofibers were solution-blown and collected on a rotating drum as fiber mats. Tensile tests of rectangular strips of these mats revealed their stress-strain dependences. These dependences were linear at low strains which correspond to their elastic behavior. Then, a plastic-like nonlinearity sets in, which is followed by catastrophic rupture. Parameters such as Young’s modulus, yield stress, and specific strain energy were measured. The results were rationalized in the framework of the phenomenological elastic-plastic model, as well as a novel micromechanical model (the latter attributes plasticity to bond rapture between the individual overstressed fibers in the mat). Besides, the effects of stretching history, rate of stretching, and winding velocity of the collector drum on the strength-related parameters are studied. The results for soy protein/nylon 6 nanofiber mats are also compared to those for solution blown pure nylon 6 mats, which were produced and tested in the same way. DA - 2012/2/15/ PY - 2012/2/15/ DO - 10.1063/1.3682757 VL - 111 IS - 4 SP - SN - 0021-8979 ER - TY - JOUR TI - Influence of polymer type, composition, and interface on the structural and mechanical properties of core/sheath type bicomponent nonwoven fibers AU - Dasdemir, Mehmet AU - Maze, Benoit AU - Anantharamaiah, Nagendra AU - Pourdeyhimi, Behnam T2 - JOURNAL OF MATERIALS SCIENCE DA - 2012/8// PY - 2012/8// DO - 10.1007/s10853-012-6499-7 VL - 47 IS - 16 SP - 5955-5969 SN - 0022-2461 ER - TY - JOUR TI - Simultaneous study of cure kinetics and rheology of montmorillonite/vinyl ester resin nanocomposites AU - Akhlaghi, Shahin AU - Kalaee, Mohammadreza AU - Jowdar, Effat AU - Nouri, Ali AU - Mazinani, Saeedeh AU - Afshari, Mehdi AU - Famili, Mohamadhosein Navid AU - Amini, Navid AU - Behrouz, Toktam T2 - POLYMERS FOR ADVANCED TECHNOLOGIES AB - Abstract In this work, the effect of quaternary ammonium salt containing nanoclay content (1–5 wt%) on phase morphology, rheology, cure kinetics, and mechanical properties of the vinyl ester resin (VER)‐based nanocomposites was studied. The morphological characterization including d‐spacing measurement, microscopy observation and phase‐height image processing were performed on the prepared nanocomposites using small angel X‐ray scattering (SAXS), transmission electron microscopy (TEM) and atomic force microscopy (AFM). According to the results obtained from these techniques, it was concluded that an intercalated morphology existed for all the nanocomposites. The kinetic analyses of the isothermal curing followed by storage modulus obtained from the rheometry experiments are shown to be an affective rheological characteristic to investigate the cure behavior of VER/clay nanocomposites. In addition, the most important finding regarding the effect of nanoclay on the cross‐linking behavior of VER systems lays on the chemisorption and physisorption of the reacting monomers and initiator molecules on the nanoclay platelets surface which is found to be responsible for the retardation of the cure reaction caused by organoclay. Eventually, the mechanical characterizations were performed through the tensile, flexural and impact analysis tests. In this case, a considerable improvement of the bulk mechanical responses such as tensile and flexural strengths and also the corresponding moduli were observed for the nanocomposites. Copyright © 2011 John Wiley & Sons, Ltd. DA - 2012/3// PY - 2012/3// DO - 10.1002/pat.1912 VL - 23 IS - 3 SP - 534-544 SN - 1099-1581 KW - nanocomposite KW - vinyl ester resin KW - rheology KW - cure kinetics KW - morphology KW - mechanical properties ER - TY - JOUR TI - Mesoscopic Simulations of the Phase Behavior of Aqueous EO19PO29EO19 Solutions Confined and Sheared by Hydrophobic and Hydrophilic Surfaces AU - Liu, Hongyi AU - Li, Yan AU - Krause, Wendy E. AU - Pasquinelli, Melissa A. AU - Rojas, Orlando J. T2 - ACS APPLIED MATERIALS & INTERFACES AB - The MesoDyn method is used to investigate associative structures in aqueous solution of a nonionic triblock copolymer consisting of poly(propylene oxide) capped on both ends with poly(ethylene oxide) chains. The effect of adsorbing (hydrophobic) and nonadsorbing (hydrophilic) solid surfaces in contact with aqueous solutions of the polymer is elucidated. The macromolecules form self-assembled structures in solution. Confinement under shear forces is investigated in terms of interfacial behavior and association. The formation of micelles under confinement between hydrophilic surfaces occurs faster than in bulk aqueous solution while layered structures assemble when the polymers are confined between hydrophobic surfaces. Micelles are deformed under shear rates of 1 μs(-1) and eventually break to form persistent, adsorbed layered structures. As a result, surface damage under frictional forces is prevented. Overall, this study indicates that aqueous triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) (Pluronics, EO(m)PO(n)EO(m)) act as a boundary lubricant for hydrophobic surfaces but not for hydrophilic ones. DA - 2012/1// PY - 2012/1// DO - 10.1021/am200917h VL - 4 IS - 1 SP - 87-95 SN - 1944-8252 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84863067883&partnerID=MN8TOARS KW - triblock nonionic polymers KW - pluronics KW - MesoDyn KW - lubrication KW - boundary layer KW - spherical micelles KW - cylindrical micelles KW - wormlike micelles ER - TY - JOUR TI - Electrospun carbon nanofibers decorated with various amounts of electrochemically-inert nickel nanoparticles for use as high-performance energy storage materials AU - Ji, Liwen AU - Lin, Zhan AU - Alcoutlabi, Mataz AU - Toprakci, Ozan AU - Yao, Yingfang AU - Xu, Guanjie AU - Li, Shuli AU - Zhang, Xiangwu T2 - RSC ADVANCES AB - Carbon nanofibers decorated with various amounts of electrochemically-inert metallic nickel nanoparticles are synthesized through electrospinning and carbonization processes. The morphology and composition of Ni nanoparticles in carbon nanofibers are controlled by preparing different nanofiber precursors. The lithium-ion battery performance evaluations indicated that the content of electrochemically-inert Ni nanoparticles in carbon nanofibers has a great influence on the final electrochemical performance. For example, at certain Ni contents, these composite nanofibers display excellent electrochemical performance, such as high reversible capacities, good capacity retention, and excellent rate performance, when directly used as binder-free anodes for rechargeable lithium-ion batteries. However, when the Ni content is too low or too high, the corresponding electrodes show low reversible capacities although they still have good reversibility and rate performance. DA - 2012/// PY - 2012/// DO - 10.1039/c1ra00676b VL - 2 IS - 1 SP - 192-198 SN - 2046-2069 UR - https://publons.com/publon/674391/ ER - TY - JOUR TI - Synthesis of novel stilbene-alkoxysilane fluorescent brighteners, and their performance on cotton fiber as fluorescent brightening and ultraviolet absorbing agents AU - Hussain, Maqbool AU - Shamey, Renzo AU - Hinks, David AU - El-Shafei, Ahmed AU - Ali, Syed Ishrat T2 - DYES AND PIGMENTS AB - Two novel fluorescent brightening agents (compounds 3a–b shown in Figure 1) were synthesized, using a facile three-step synthetic route, from 4,4′-diamino-2,2′-disulfonic-stilbene, cyanuric chloride, and a readily cross-linkable 3-aminopropyltrimethoxy silane. The products contain hydrolytically active trimethoxysilyl, (–Si(OCH)3), functional groups that readily hydrolyze in the presence of water, and subsequently generate a water insoluble silicon cross-linked-network (Si–O–Si) via a condensation process. The cross-linked product hydrolyzes on treatment with hot aqueous sodium hydroxide to silanols (–Si(OH)3) to form compounds 4a–b which are readily water soluble and produce a clear fluorescent solution. The silanol forms of compounds 4a–b were used for further characterization and performance evaluation. The structures of compounds 4a–b were characterized by 1H-NMR, Fourier-Transform infrared (FT-IR) spectroscopy and negative electrospray ionization mass (−ESI-MS) spectroscopy. Compounds were applied to cotton fiber as fluorescent brightening agents and their performance was evaluated by measuring the degree of whiteness, ultraviolet protection factor (UPF), fluorescence and acid fastness. Results showed that application of 0.25% (o.w.f) of compounds 4a–b impart a high degree of whiteness (CIE WI = 144, 139) as well as good ultraviolet protection factor (UPF = 29, 27) on cotton fiber exhibiting a significant increase in whiteness and UV blocking properties compared to untreated substrate (CIE WI = 81, UPF = 5). Acid fastness tests of both compounds showed a slight change in fluorescence emission intensities as a function of pH. In acidic solutions, a shift in emission maximum occurs at pH 3 from 434 to 453 nm and from 435 to 457 nm, due to the protonation of amino and sulfonic groups of stilbene fluorophore which substantially reduces the quenching process. DA - 2012/3// PY - 2012/3// DO - 10.1016/j.dyepig.2011.06.034 VL - 92 IS - 3 SP - 1231-1240 SN - 1873-3743 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-80053923377&partnerID=MN8TOARS KW - Fluorescent brightening agent KW - Ultraviolet absorbing agents KW - Stilbene KW - Alkoxysilane KW - Whiteness KW - Ultraviolet protection factor ER - TY - JOUR TI - Modification of Melt-Spun Isotactic Polypropylene and Poly(lactic acid) Bicomponent Filaments with a Premade Block Copolymer AU - Arvidson, Sara A. AU - Roskov, Kristen E. AU - Pate, Jaimin J. AU - Spontak, Richard J. AU - Khan, Saad A. AU - Gorga, Russell E. T2 - MACROMOLECULES AB - While numerous studies have investigated the effect of adding a block copolymer as a macromolecular surfactant to immiscible polymer blends, no such efforts have sought to alter the properties of melt-spun bicomponent core–sheath filaments with a nonreactive compatibilizing agent. In this study, we examine the effect of adding poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS) triblock copolymer to core–sheath filaments consisting of isotactic polypropylene (iPP) and poly(lactic acid) (PLA). Incorporation of the copolymer into blends of iPP/PLA is observed to reduce the size scale of phase separation. Interfacial slip between molten iPP and PLA layers is evaluated by rheology under steady-shear conditions. Addition of SEBS to the PLA sheath during filament formation reduces the tendency of PLA sheaths to crack prior to iPP core failure during tensile testing. In reversed filament configurations, the copolymer does not hinder the development of molecular orientation, related to fiber strength, during fiber spinning. Electron microscopy reveals that the copolymer molecules form unique, highly nonequilibrium morphologies under the spinning conditions employed here. DA - 2012/1/24/ PY - 2012/1/24/ DO - 10.1021/ma202246h VL - 45 IS - 2 SP - 913-925 SN - 1520-5835 ER - TY - JOUR TI - Mechanisms for hydrophilic/hydrophobic wetting transitions on cellulose cotton fibers coated using Al2O3 atomic layer deposition AU - Lee, Kyoungmi AU - Jur, Jesse S. AU - Kim, Do Han AU - Parsons, Gregory N. T2 - JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A AB - This report explores reactions that proceed during the first few cycles of inorganic film atomic layer deposition (ALD) on natural cellulose cotton fibers, and how surface reactions can explain the previously observed transitions in surface wetting upon ALD on cotton fibers. Atomic layer deposition of aluminum oxide and zinc oxide onto natural cotton cellulose produces a transition from hydrophilic to hydrophobic, then from hydrophobic back to hydrophilic, and we describe here the main factors that bring about. Interestingly, we show that air exposure and related adventitious carbon adsorption also affects the subsequent reactions and wetting properties obtained after subsequent ALD cycles. X-ray photoelectron spectroscopy and in situ Fourier transform infrared spectroscopy data indicate Al-(O-C-)3 bonding units form when trimethylaluminum interacts with surface –OH units during the first precursor doses, producing a hydrophobic finish on the cotton that remains for only a few ALD cycles. Also, field-emission scanning electron microscopy results show that some surface roughening may occur in the first few ALD cycles, and the roughening of the hydrophobic-finished surface can also promote an increase in measured hydrophobicity. DA - 2012/1// PY - 2012/1// DO - 10.1116/1.3671942 VL - 30 IS - 1 SP - SN - 0734-2101 ER - TY - JOUR TI - Enhanced Biomimetic Performance of Ionic Polymer-Metal Composite Actuators Prepared with Nanostructured Block Ionomers AU - Vargantwar, Pruthesh H. AU - Roskov, Kristen E. AU - Ghosh, Tushar K. AU - Spontak, Richard J. T2 - MACROMOLECULAR RAPID COMMUNICATIONS AB - Abstract Ionic polymer–metal composites (IPMCs) represent an important class of stimuli‐responsive polymers that are capable of bending upon application of an electric potential. Conventional IPMCs, prepared with Nafion and related polyelectrolytes, often suffer from processing challenges, relatively low actuation levels and back relaxation during actuation. In this study, we examine and compare the effects of fabrication and solvent on the actuation behavior of a block ionomer with a sulfonated midblock and glassy endblocks that are capable of self‐organizing and thus stabilizing a molecular network in the presence of a polar solvent. Unlike Nafion, this material can be readily dissolved and cast from solution to yield films that vary in thickness and exhibit enormous solvent uptake. Cycling the initial chemical deposition of Pt on the surfaces of swollen films (the compositing process) increases the extent to which the electrodes penetrate the films, thereby improving contact along the polymer/electrode interface. The maximum bending actuation measured from IPMCs prepared with different solvents is at least comparable, but is often superior, to that reported for conventional IPMCs, without evidence of back relaxation. An unexpected characteristic observed here is that the actuation direction can be solvent regulated. Our results confirm that this block ionomer constitutes an attractive alternative for use in IPMCs and their associated applications. DA - 2012/1/16/ PY - 2012/1/16/ DO - 10.1002/marc.201100535 VL - 33 IS - 1 SP - 61-68 SN - 1022-1336 KW - block ionomer KW - electroactive polymer KW - ionic polymer-metal composite KW - ion transport KW - polyelectrolyte KW - stimulti-responsive polymer ER - TY - JOUR TI - Effect of temperature and gas velocity on growth per cycle during Al2O3 and ZnO atomic layer deposition at atmospheric pressure AU - Mousa, Moataz Bellah M. AU - Oldham, Christopher J. AU - Jur, Jesse S. AU - Parsons, Gregory N. T2 - JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A AB - The growth per cycle as a function of temperature during atomic layer deposition (ALD) of Al2O3 and ZnO at atmospheric pressure follows very closely the trend measured at typical (∼2 Torr) process pressure. However, the overall growth rate is found to be nearly 2 × larger at higher pressure and the magnitude of the growth increase can be adjusted by controlling the gas velocity near the growth surface. The growth increase at high pressure is approximately independent of process temperature at T < 200 °C for Al2O3 and ZnO, but the effect begins to become less pronounced at T > 150 °C, especially for Al2O3. The relatively high growth/cycle measured at 760 Torr and T < 150 °C suggests that excess physisorbed water remains on the alumina or zinc oxide surface after the water purge step. Increasing the gas velocity in the growth zone reduces the growth rate, consistent with more efficient removal of excess water. To better understand the observed trends, we present analytical expressions for the boundary layer thickness and species diffusivity and describe how these parameters are affected by reactor pressure and bulk gas velocity in the low temperature regime. To optimize ALD films and products, new ALD schemes at ambient pressure will need to understand the interaction between reactor pressure, gas velocity near the growth surface, fluid boundary layer thickness, and product desorption and diffusivity to achieve controlled growth. DA - 2012/1// PY - 2012/1// DO - 10.1116/1.3670961 VL - 30 IS - 1 SP - SN - 1520-8559 ER - TY - JOUR TI - Effect of stabilizer on the mechanical, morphological and thermal properties of compatibilized high density polyethylene/ethylene vinyl acetate copolymer/organoclay nanocomposites AU - Akhlaghi, Shahin AU - Sharif, Alireza AU - Kalaee, Mohammadreza AU - Elahi, Alireza AU - Pirzadeh, Mohammadhadi AU - Mazinani, Saeedeh AU - Afshari, Mehdi T2 - MATERIALS & DESIGN AB - In this work, the effects of a phosphate containing stabilizer on the mechanical, morphological and thermal properties of a compatibilized high density polyethylene (HDPE)/ethylene vinyl acetate (EVA) blend containing an ammonium quaternary salts modified montmorillonite were studied from both statistical and experimental aspects. According to the results obtained from simultaneous implementation of analysis of variance (ANOVA) and mean effect assessment, the formulations designed based on the optimized coupling of stabilizer into organoclay/compatibilizer system exhibited the highest tensile properties among the prepared samples. From experimental point of view, the d-spacing measurements and microscopy observations through X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively, revealed that the stabilizer not only favored the penetration of the polymeric chains between the silicate layers but also contributed to provide finer dispersion of the minor phase in the matrix. Thermal characterizations using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) showed that the stabilizer could play a role in prevention of the organic modifier of the nanoclay to undergo thermo-oxidative degradation by hindering the SN2 nucleophilic substitution reactions between alkyl ammonium chains and oxygen molecules. This, we believe, is responsible for the properties enhancement, since the protective role of stabilizer might inhibit the formation of destructive degradation products which could collapse the organoclay tactoids and also deactivate the anhydride groups of the compatibilizer. DA - 2012/1// PY - 2012/1// DO - 10.1016/j.matdes.2011.07.044 VL - 33 SP - 273-283 SN - 0261-3069 KW - Nanomaterials KW - Mechanical KW - Selection for material properties ER - TY - JOUR TI - The Soft-Confined Method for Creating Molecular Models of Amorphous Polymer Surfaces AU - Liu, Hongyi AU - Li, Yan AU - Krause, Wendy E. AU - Rojas, Orlando J. AU - Pasquinelli, Melissa A. T2 - JOURNAL OF PHYSICAL CHEMISTRY B AB - The goal of this work was to use molecular dynamics (MD) simulations to build amorphous surface layers of polypropylene (PP) and cellulose and to inspect their physical and interfacial properties. A new method to produce molecular models for these surfaces was developed, which involved the use of a "soft" confining layer comprised of a xenon crystal. This method compacts the polymers into a density distribution and a degree of molecular surface roughness that corresponds well to experimental values. In addition, calculated properties such as density, cohesive energy density, coefficient of thermal expansion, and the surface energy agree with experimental values and thus validate the use of soft confining layers. The method can be applied to polymers with a linear backbone such as PP as well as those whose backbones contain rings, such as cellulose. The developed PP and cellulose surfaces were characterized by their interactions with water. It was found that a water nanodroplet spreads on the amorphous cellulose surfaces, but there was no significant change in the dimension of the droplet on the PP surface; the resulting MD water contact angles on PP and amorphous cellulose surfaces were determined to be 106 and 33°, respectively. DA - 2012/2/9/ PY - 2012/2/9/ DO - 10.1021/jp209024r VL - 116 IS - 5 SP - 1570-1578 SN - 1520-6106 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84863136276&partnerID=MN8TOARS ER - TY - JOUR TI - High-rate capability of LiFePO4 cathode materials containing Fe2P and trace carbon AU - Yin, Yuehui AU - Gao, Mingxia AU - Pan, Hongge AU - Shen, Lukai AU - Ye, Xin AU - Liu, Yongfeng AU - Fedkiw, Peter S. AU - Zhang, Xiangwu T2 - JOURNAL OF POWER SOURCES AB - Carbon coating and nano-scale particle size are two impactful factors in improving the rate capability of LiFePO4 cathode materials for lithium-ion batteries. However, both factors decrease the tap density of the materials and are possibly causing unfavorable effect on the volumetric capacity of the cathode materials and thus the batteries, which is undesirable in commercial application. In the present study, LiFePO4 materials with moderate particle size of sub-micron and trace carbon content (0.5–0.9 wt.%) are synthesized by a mechanical activation method. High-electronic conductivity iron phosphides (Fe2P/FeP) are in situ introduced into the LiFePO4 materials and the amount is modified by the calcination temperature. Electrochemical testing shows that Fe2P/FeP plays an important role in improving the high-rate capability of LiFePO4 with moderate particle size. The product calcined at 700 °C, which has a high-tap density of 1.37 g cm−3 correlating to a specific surface area approximately of 4 m2 g−1, possesses discharge capacities of 110 and 100 mAh g−1 at discharge rates of 5 C and 10 C, respectively. The introduction of Fe2P/FeP in an amount of ca. 5 wt.% rather than carbon coating and the moderate particle size of LiFePO4 are promising approaches to obtain LiFePO4 cathode material of high-rate capability without unduly compromising its volumetric capacity. DA - 2012/2/1/ PY - 2012/2/1/ DO - 10.1016/j.jpowsour.2011.10.042 VL - 199 SP - 256-262 SN - 0378-7753 UR - https://publons.com/publon/4984276/ KW - Lithium-ion battery KW - Lithium iron phosphate KW - Particle size KW - Rate capability KW - Mechanical activation ER - TY - JOUR TI - Constrained polymer chain behavior observed in their non-stoichiometric cyclodextrin inclusion complexes AU - Williamson, B. R. AU - Tonelli, A. E. T2 - Journal of Inclusion Phenomena and Macrocyclic Chemistry DA - 2012/// PY - 2012/// DO - 10.1007/s10847-011-9940-7 VL - 72 IS - 1-2 SP - 71-78 ER - TY - JOUR TI - Selective Permeation of Cross-Linked Polyelectrolyte and Polyelectrolyte-Filled Nonwoven Membranes AU - Jung, Kyung-Hye AU - Pourdeyhimi, Behnam AU - Zhang, Xiangwu T2 - JOURNAL OF APPLIED POLYMER SCIENCE AB - Abstract Selective permeation, driven by ionic attraction, is one of the most important properties of polyelectrolyte membranes. In this study, selective permeation behaviors of different polyelectrolytes, poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) (PAMPS), poly(styrene sulfonic acid) (PSS), and poly(methacrylic acid) (PMA), were studied via solution‐diffusion mechanism. Among these three polyelectrolytes, PSS membranes showed the highest permeabilities for both water and dimethyl methylphophonate vapors due to their high diffusion coefficients caused by the high flexibility of PSS chains. It was also found that the cross‐linking of polymer chains increased membrane permeabilities by weakening the physical network formed by ionic attraction. However, the type and cross‐linking of polyelectrolytes did not have significant effect on the membrane selectivities. Nonwoven fabric was employed to control the selective permeation of polyelectrolyte membranes. It was found that filling the nonwoven fabric with polyelectrolytes led to composite membranes with reduced permeabilities and increased selectivities. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011. DA - 2012/1/5/ PY - 2012/1/5/ DO - 10.1002/app.34453 VL - 123 IS - 1 SP - 227-233 SN - 0021-8995 UR - https://publons.com/publon/7178357/ KW - membranes KW - crosslinking KW - diffusion ER - TY - JOUR TI - Molecular dynamics simulations of interactions between polyanilines in their inclusion complexes with β-cyclodextrins AU - Tallury, Syamal S. AU - Smyth, Margaret B. AU - Cakmak, Enes AU - Pasquinelli, Melissa A. T2 - Journal of Physical Chemistry B AB - Conductive polymers have several applications such as in flexible displays, solar cells, and biomedical sensors. An inclusion complex of a conductive polymer and cyclodextrin is desired for some applications such as for molecular wires. In this study, different orientations of β-cyclodextrin rings on a single polyaniline (PANI) chain in an alternating emeraldine form were simulated using molecular dynamics. The simulations were performed in an implicit solvent environment that corresponds to experimental conditions. When the larger opening of the β-cyclodextrin toroids face the same direction, the cyclodextrins tend to repel each other. Alternating the orientation of the β-cyclodextrins on the chain causes the β-cyclodextrin rings to be more attractive to one another and form pairs or stacks of rings. These simulations explain how the β-cyclodextrins can be used to shield the polyaniline from outside chemical action by analyzing the PANI/cyclodextrin interactions from a molecular perspective. DA - 2012/// PY - 2012/// DO - 10.1021/jp206745q VL - 116 IS - 7 SP - 2023-2030 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84857387776&partnerID=MN8TOARS ER - TY - JOUR TI - Effects of Material and Treatment Parameters on Noise-Control Performance of Compressed Three-Layered Multifiber Needle-Punched Nonwovens AU - Yilmaz, Nazire Deniz AU - Michielsen, Stephen AU - Banks-Lee, Pamela AU - Powell, Nancy B. T2 - JOURNAL OF APPLIED POLYMER SCIENCE AB - Abstract The effects of material and treatment parameters on airflow resistivity and normal‐incidence sound absorption coefficient (NAC) of compressed three‐layer nonwoven composites have been studied. Material parameters included fiber size and porosity, and treatment factors included applied pressure and duration of compression. Fibers used included poly(lactic acid) (PLA), polypropylene (PP), glassfiber, and hemp. Three‐layered nonwoven composites were classified based on material content and fiber blend. LHL and PGP were sandwiched structures consisting of PLA/Hemp/PLA and PP/glassfiber/PP layers, respectively. PGI consisted of three layers of an intimate blend of PP and glassfiber. Statistical models were developed to predict air flow resistivity from material parameters and the change in air flow resistivity from compression parameters. Independent variables in the first model were porosity and fiber size and, in the latter model, were compressibility, pressure, and initial material parameters. An increase in air flow resistivity was found with increased compression. No significant effect of compression duration was detected. Two additional statistical models were developed for the prediction of sound absorption coefficient based on material and treatment parameters. The independent variables of the first model were air flow resistivity, thickness, and frequency, and those of the second model were compressibility, initial thickness, and initial density of the composite, diameter and density of the fiber, compression pressure, and frequency. A decrease in sound absorption coefficient was detected with increasing compression, while no effect of duration was detected. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 DA - 2012/2/15/ PY - 2012/2/15/ DO - 10.1002/app.34712 VL - 123 IS - 4 SP - 2095-2106 SN - 1097-4628 UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000297932300024&KeyUID=WOS:000297932300024 KW - sound absorption KW - compression KW - nonwoven KW - layered composites KW - biodegradable ER - TY - JOUR TI - Structure, molecular orientation, and resultant mechanical properties in core/sheath poly(lactic acid)/polypropylene composites AU - Arvidson, Sara A. AU - Wong, Ka C. AU - Gorga, Russell E. AU - Khan, Saad A. T2 - POLYMER AB - We study the coaxial spinning of poly(lactic acid) (PLA) with polypropylene (PP) in a core/sheath configuration. PPcore/PLAsheath and PLAcore/PPsheath fibers maintain the high breaking strength that PP and PLA exhibit individually, showing marked improvement in strength over previous reports of PP/PLA blend fibers. Crystalline morphologies are greatly affected by the location within the fiber (i.e., core, sheath, or spun individually), and hence, co-spinning provides a route to tailor the morphology and fiber diameter beyond that available with single component fibers. A new approach to estimate molecular orientation of core sheath fibers based on the tensile response of the fiber is developed, and indicates that co-spinning PP with PLA results in a synergistic effect with increases in the molecular orientation above that which is possible with spinning either PP or PLA individually. DA - 2012/2// PY - 2012/2// DO - 10.1016/j.polymer.2011.12.042 VL - 53 IS - 3 SP - 791-800 SN - 0032-3861 KW - Polypropylene KW - Poly(lactic acid) KW - Core/sheath fiber ER -