@article{smith_gehring_riviere_yeatts_baynes_2004, title={Elimination kinetics of ceftiofur hydrochloride after intramammary administration in lactating dairy cows}, volume={224}, ISSN={0003-1488}, url={http://dx.doi.org/10.2460/javma.2004.224.1827}, DOI={10.2460/javma.2004.224.1827}, abstractNote={Abstract}, number={11}, journal={Journal of the American Veterinary Medical Association}, publisher={American Veterinary Medical Association (AVMA)}, author={Smith, Geof W. and Gehring, Ronette and Riviere, Jim E. and Yeatts, James L. and Baynes, Ronald E.}, year={2004}, month={Jun}, pages={1827–1830} }
 @article{winesett_ade_smith_urquhart_dias_stevens_2003, title={Application of scanning transmission X-ray microscopy to the rubber industry}, volume={76}, ISSN={["1943-4804"]}, DOI={10.5254/1.3547773}, abstractNote={Abstract}, number={4}, journal={RUBBER CHEMISTRY AND TECHNOLOGY}, author={Winesett, DA and Ade, H and Smith, AP and Urquhart, SG and Dias, AJ and Stevens, P}, year={2003}, pages={803–811} }
 @article{rightor_urquhart_hitchcock_ade_smith_mitchell_priester_aneja_appel_wilkes_et al._2002, title={Identification and quantitation of urea precipitates in flexible polyurethane foam formulations by X-ray spectromicroscopy}, volume={35}, ISSN={["1520-5835"]}, DOI={10.1021/ma0122627}, abstractNote={Scanning transmission X-ray microscopy (STXM) and atomic force microscopy have been used to study the morphology and chemical composition of macrophase-segregated block copolymers in plaque formulations based on water-blown flexible polyurethane foams. Although there has been a large body of indirect evidence indicating that the observed macrophase-segregated features in water-rich polyurethane foams are due principally to urea components, this work provides the first direct, spatially resolved spectroscopic proof to support this hypothesis. The STXM results are consistent with a segregation model where urea segments segregate, forming enriched phases with the majority of the polyether- polyol and urethane groups at the chain ends of the urea hard segments. Chemical mapping of the urea, urethane, and polyether distribution about the urea-rich segregated phases showed that the urea concentration changes gradually (across several hundred nanometers) in a butylene oxide-based foam. This mapping also showed the urea-rich segregated phases present as a partial network in an ethylene oxide/propylene oxide sample.}, number={15}, journal={MACROMOLECULES}, author={Rightor, EG and Urquhart, SG and Hitchcock, AP and Ade, H and Smith, AP and Mitchell, GE and Priester, RD and Aneja, A and Appel, G and Wilkes, G and et al.}, year={2002}, month={Jul}, pages={5873–5882} }
 @article{smith_ade_smith_koch_spontak_2001, title={Anomalous phase inversion in polymer blends prepared by cryogenic mechanical alloying}, volume={34}, ISSN={["1520-5835"]}, DOI={10.1021/ma001151p}, abstractNote={offer alternative strategies for producing highly dis-persed multicomponent polymer blends. By their verynature, these processes yield fine powders, which mustbe subsequently consolidated or melt-processed to formobjects. While nanoscale dispersion of one polymerwithin the matrix of another has been achieved withoutcompatibilizing agents in binary blends produced byCMA,}, number={6}, journal={MACROMOLECULES}, author={Smith, AP and Ade, H and Smith, SD and Koch, CC and Spontak, RJ}, year={2001}, month={Mar}, pages={1536–1538} }
 @article{smith_ade_koch_spontak_2001, title={Cryogenic mechanical alloying as an alternative strategy for the recycling of tires}, volume={42}, ISSN={["0032-3861"]}, DOI={10.1016/S0032-3861(00)00804-1}, abstractNote={Cryogenic mechanical alloying (CMA) is investigated as a viable strategy by which to produce highly dispersed blends composed of thermoplastics and tire, thereby providing a potentially new route by which to recycle discarded tires. Morphological characterization of these blends by near-edge X-ray absorption fine structure (NEXAFS) microscopy demonstrates that, upon CMA, ground tire is highly dispersed within poly(methyl methacrylate) (PMMA) and poly(ethylene terephthalate) (PET) matrices at sub-micron size scales. Incorpo-ration of polyisoprene (PI) homopolymer into the blends to improve dispersion efficacy is also examined. Neither PI nor the tire is found to interact chemically with PMMA or PET under the milling conditions employed here.}, number={9}, journal={POLYMER}, author={Smith, AP and Ade, H and Koch, CC and Spontak, RJ}, year={2001}, month={Apr}, pages={4453–4457} }
 @article{sloop_ade_fornes_gilbert_smith_2001, title={Near-edge X-ray absorption fine structure (NEXAFS) microscopy of a polycarbonate/poly (acrylonitrile/butadiene/styrene) blend}, volume={39}, ISSN={["1099-0488"]}, DOI={10.1002/1099-0488(20010301)39:5<531::AID-POLB1026>3.0.CO;2-Q}, abstractNote={Blends of polycarbonate (PC), poly(styrene/acrylonitrile) (SAN), and polybutadiene (PB), commonly called PC/acrylonitrile–butadiene–styrene (ABS) blends, are complex mixtures. The ABS component consists of free SAN copolymer and SAN grafted onto PB (SAN-g-PB). PC/ABS blends are materials that typically require heavy metal staining to differentiate the separate phases at a high spatial resolution in an electron microscope. Our eventual goal is the characterization of blends of PC and ABS as a function of increasing thermomechanical cycles. Because heavy metal staining is not directly sensitive to potential compositional changes in these polymers, we explored the characterization of PC/ABS blends with a directly sensitive imaging technique: near-edge X-ray absorption fine structure (NEXAFS) microscopy. Here we report NEXAFS spectra of the carbon K shell of PC, SAN, and SAN-gPB, and we evaluate the contrast in a PC/ABS blend across an energy range of 280–295 eV in the presence of TiO2 additives. We unambiguously observed free SAN in the PC matrix. NEXAFS spectroscopy exhibits spectral variations that are sensitive to numerous chemical functionalities and permits the characterization of the composition of organic materials. The information is analogous to what can be obtained in the near edge of core loss features in electron energy loss spectroscopy. During the last few years, the combination of NEXAFS and a high spatial resolution of about 50 nm has been achieved. The resolution has not reached a fundamental limit and is expected to approach 10 nm in the future. NEXAFS microscopy has already been used to image biological systems and examine the morphology and orientation of polymer systems near the K-shell absorption edge of carbon, oxygen, and nitrogen. NEXAFS spectroscopy without spatial resolution has also been successfully used to investigate various polymer surfaces (see refs. 19–26). One advantage of NEXAFS microscopy in imaging polymer systems is that materials of similar electron density and elemental chemistry can be differentiated and complex compositions can be quantified at much higher spatial resolutions than are possible with IR or Raman microscopy. In addition, organic materials can be differentiated directly on the basis of differences in chemical composition rather than through the indirect and aggressive Correspondence to: C. C. Sloop (E-mail: ccsloop@us. ibm.com) Present Address: National Institute of Standards and Technology, Gaithersburg, MD *Present Address: IBM Corporation, Research Triangle Park, NC}, number={5}, journal={JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS}, author={Sloop, CC and Ade, H and Fornes, RE and Gilbert, RD and Smith, AP}, year={2001}, month={Mar}, pages={531–535} }
 @article{smith_spontak_ade_2001, title={On the similarity of macromolecular responses to high-energy processes: mechanical milling vs. irradiation}, volume={72}, ISSN={["0141-3910"]}, DOI={10.1016/S0141-3910(01)00055-6}, abstractNote={Recent efforts to blend and compatibilize intrinsically immiscible polymers in the solid state by high-energy methods have shown that macromolecules may undergo scission, crosslinking or amorphization, depending on the chemical nature of the repeat unit, the processing temperature and the initial degree of polymer crystallinity. Identical process-induced molecular and structural modifications have been previously observed in polymers exposed to large doses of electron and γ radiation, suggesting that the responses of polymers to high-energy processes may be mechanistically similar. In this work, we explore a variety of similarities between mechanically-milled and irradiated polymers in terms of molecular characteristics, process temperature and polymer crystallinity, and we demonstrate that these similarities provide predictive guidance for the selection of polymers to be subjected to solid-state processing.}, number={3}, journal={POLYMER DEGRADATION AND STABILITY}, author={Smith, AP and Spontak, RJ and Ade, H}, year={2001}, pages={519–524} }
 @article{hitchcock_koprinarov_tyliszczak_rightor_mitchell_dineen_hayes_lidy_priester_urquhart_et al._2001, title={Optimization of scanning transmission X-ray microscopy for the identification and quantitation of reinforcing particles in polyurethanes}, volume={88}, ISSN={["1879-2723"]}, DOI={10.1016/S0304-3991(00)00113-3}, abstractNote={The morphology, size distributions, spatial distributions, and quantitative chemical compositions of co-polymer polyol-reinforcing particles in a polyurethane have been investigated with scanning transmission X-ray microscopy (STXM). A detailed discussion of microscope operating procedures is presented and ways to avoid potential artifacts are discussed. Images at selected photon energies in the C 1s, N 1s and O 1s regions allow unambiguous identification of styrene-acrylonitrile-based (SAN) copolymer and polyisocyanate polyaddition product-based (PIPA) reinforcing particles down to particle sizes at the limit of the spatial resolution (50 nm). Quantitative analysis of the chemical composition of individual reinforcing particles is achieved by fitting C 1s spectra to linear combinations of reference spectra. Regression analyses of sequences of images recorded through the chemically sensitive ranges of the C 1s, N 1s and O 1s spectra are used to generate quantitative compositional maps, which provide a fast and effective means of investigating compositional distributions over a large number of reinforcing particles. The size distribution of all particles determined by STXM is shown to be similar to that determined by TEM. The size distributions of each type of reinforcing particle, which differ considerably, were obtained by analysis of STXM images at chemically selective energies.}, number={1}, journal={ULTRAMICROSCOPY}, author={Hitchcock, AP and Koprinarov, I and Tyliszczak, T and Rightor, EG and Mitchell, GE and Dineen, MT and Hayes, F and Lidy, W and Priester, RD and Urquhart, SG and et al.}, year={2001}, month={Jun}, pages={33–49} }
 @article{smith_shay_spontak_balik_ade_smith_koch_2000, title={High-energy mechanical milling of poly(methyl methacrylate), polyisoprene and poly(ethylene-alt-propylene)}, volume={41}, ISSN={["0032-3861"]}, DOI={10.1016/S0032-3861(99)00830-7}, abstractNote={High-energy mechanical milling has been performed on poly(methyl methacrylate) (PMMA) at ambient and cryogenic temperatures, as well as on polyisoprene (PI) and poly(ethylene-alt-propylene) (PEP) at cryogenic conditions only. Milling conducted at ambient temperature has a substantially greater impact on the molecular characteristics of PMMA than milling at cryogenic temperatures. An increase in the milling time is accompanied by substantial reductions in PMMA molecular weight and, hence, glass transition temperature and impact strength under both sets of experimental conditions. An unexpected trend identified here is that the PMMA molecular weight distribution initially broadens and subsequently narrows with increasing milling time. Solid-state mechanical milling promotes comparable decreases in molecular weight and glass transition temperature in PEP (at a slower rate relative to PMMA), but induces chemical crosslinking in PI, as confirmed by FTIR spectroscopy. Charlesby–Pinner analysis yields not only the degree of PI crosslinking, but also the relative crosslinking and scission rates of PI, during cryogenic milling.}, number={16}, journal={POLYMER}, author={Smith, AP and Shay, JS and Spontak, RJ and Balik, CM and Ade, H and Smith, SD and Koch, CC}, year={2000}, month={Jul}, pages={6271–6283} }
 @inproceedings{koch_smith_bai_spontak_balik_2000, title={Nonequilibrium processing of polymeric materials by mechanical attrition}, volume={343/346}, number={pts.1&2}, booktitle={International Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials (1999: Dresden, Germany)}, publisher={Utikon-Zurich, Switz.; Enfield, NH: Trans Tech Publications}, author={Koch, C. C. and Smith, A. P. and Bai, C. and Spontak, R. J. and Balik, C. M.}, editor={J. Eckert, H. Schlorb and Schultz, L.Editors}, year={2000}, pages={49–561} }
 @article{smith_spontak_koch_smith_ade_2000, title={Temperature-induced morphological evolution in polymer blends produced by cryogenic mechanical alloying}, volume={274}, DOI={10.1002/(sici)1439-2054(20000101)274:1<1::aid-mame1>3.3.co;2-r}, number={1}, journal={Macromolecular Materials and Engineering}, author={Smith, A. P. and Spontak, Richard and Koch, C. C. and Smith, S. D. and Ade, H.}, year={2000}, pages={1–12} }
 @article{ade_smith_zhang_zhuang_kirz_rightor_hitchcock_1997, title={X-ray spectromicroscopy of polymers and tribological surfaces at beamline X1A at the NSLS}, volume={84}, ISSN={["1873-2526"]}, DOI={10.1016/S0368-2048(97)00013-3}, abstractNote={We provide a general overview of microspectroscopy and spectromicroscopy for materials characterization at beamline X1A at the national synchrotron light source (NSLS). Two instruments, the scanning transmission X-ray microscope (STXM) and scanning photoemission microscope (SPEM), are available. The STXM has been able to provide a spatial resolution of better than 50 nm for several years and near edge X-ray absorption fine structure (NEXAFS) spectroscopy is performed in transmission from thin samples at an energy resolution of typically 0.3 eV at the carbon K-edge. Numerous applications in polymer science and biology have been performed to date. We restrict our review to polymer science applications and present new results of several polymer systems. The SPEM has a spatial resolution of about 250 nm in routine operation and was recently upgraded with a hemispherical sector analyzer to improve the data throughput. We present the latest SPEM results, which were generated from a tribological sample.}, number={1-3}, journal={JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA}, author={Ade, H and Smith, AP and Zhang, H and Zhuang, GR and Kirz, J and Rightor, E and Hitchcock, A}, year={1997}, month={Mar}, pages={53–71} }