@article{karaaslan_kadla_ko_2016, title={Lignin-based aerogels}, journal={Lignin in Polymer Composites}, author={Karaaslan, M. A. and Kadla, J. F. and Ko, F. K.}, year={2016}, pages={67–93} }
 @article{ko_goudarzi_lin_li_kadla_2016, title={Lignin-based composite carbon nanofibers}, journal={Lignin in Polymer Composites}, author={Ko, F. K. and Goudarzi, A. and Lin, L. T. and Li, Y. J. and Kadla, J. F.}, year={2016}, pages={167–194} }
 @article{dodd_kadla_straus_2015, title={Characterization of Fractions Obtained from Two Industrial Softwood Kraft Lignins}, volume={3}, ISSN={["2168-0485"]}, DOI={10.1021/sc500601b}, abstractNote={With increasing interest in using lignin as an alternative material to petroleum-based chemicals (e.g., in the manufacture of carbon fibers or adhesives), it is becoming important to understand what properties of lignin are required to impart key features in the final product. Commercial lignins are complex, heterogeneous, macromolecular mixtures. To obtain maximum value, lignins will require classification and possibly fractionation or modification to improve properties and enable their utilization in high-value applications. To this end, the physicochemical properties of fractions derived from two industrial softwood Kraft lignins (New Bern Mill, Weyerhaeuser, U.S.A., and Backhammar Mill in Kristinehamn, Sweden) have been determined and compared to previously published data on commercially available Indulin AT lignin from MeadWestvaco.1,2 The fractions were obtained by successive extraction with organic solvents and analyzed using a range of techniques (e.g., DSC, 13C NMR, 31P NMR). The results showed t...}, number={1}, journal={ACS SUSTAINABLE CHEMISTRY & ENGINEERING}, author={Dodd, Angela P. and Kadla, John F. and Straus, Suzana K.}, year={2015}, month={Jan}, pages={103–110} }
 @article{korehei_olson_ko_kadla_2015, title={Influence of the solvent and nonsolvent composition on the electrospinning of a cellulose acetate ternary system}, volume={132}, ISSN={["1097-4628"]}, DOI={10.1002/app.42819}, abstractNote={ABSTRACT}, number={47}, journal={JOURNAL OF APPLIED POLYMER SCIENCE}, author={Korehei, Reza and Olson, James and Ko, Frank and Kadla, John}, year={2015}, month={Dec} }
 @article{gao_ko_kadla_2015, title={Synthesis of Noble Monometal and Bimetal-Modified Lignin Nanofibers and Carbon Nanofibers Through Surface-Grafted Poly(2-(Dimethylamino)Ethyl Methacrylate) Brushes}, volume={300}, ISSN={["1439-2054"]}, DOI={10.1002/mame.201500006}, abstractNote={Various noble monometallic and bimetallic nanoparticles, including Pd, Pt, Au, Pd/Pt, Pd/Au, and Pt/Au, deposited lignin nanofiber mats (LFMs), and lignin carbon nanofiber mats (LCFMs) were fabricated using a novel lignin fiber surface PDMAEMA brush‐guided strategy. PDMAEMA brushes were immobilized on lignin nanofiber mat surfaces by surface‐initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET‐ATRP) in an aqueous solution followed by monometallic nanoparticle deposition. For the Pd and Pt nanoparticle‐immobilized LFMs, the metallic ions were reduced using citric acid and ascorbic acid, respectively; however, for the Au nanoparticle‐immobilized LFMs, in‐situ reduction occurred via the reducing potential of the PDMAEMA. The process was repeated to produce the bimetallic, Pd/Pt, Pd/Au, and Pt/Au‐immobilized lignin nanofiber mats. The resultant mono and bimetallic nanoparticle‐immobilized LFMs were then carbonized to the corresponding metallic‐modified carbon nanofibers. XPS, XRD, and SEM were used to confirm the uniformity of nanoparticle deposition and the metallic state on the lignin fiber and carbon nanofiber surfaces.}, number={8}, journal={MACROMOLECULAR MATERIALS AND ENGINEERING}, author={Gao, Guangzheng and Ko, Frank and Kadla, John F.}, year={2015}, month={Aug}, pages={836–847} }
 @article{gao_karaaslan_kadla_ko_2014, title={Enzymatic synthesis of ionic responsive lignin nanofibres through surface poly(N-isopropylacrylamide) immobilization}, volume={16}, ISSN={["1463-9270"]}, DOI={10.1039/c4gc00757c}, abstractNote={Surface modification of electrospun lignin nanofibres with poly(N-isopropylacrylamide) (PNIPAM) was conducted through surface-initiated atom transfer radical polymerization (ATRPase) using various biocatalysts under aqueous conditions.}, number={8}, journal={GREEN CHEMISTRY}, author={Gao, Guangzheng and Karaaslan, Muzaffer A. and Kadla, John F. and Ko, Frank}, year={2014}, month={Aug}, pages={3890–3898} }
 @article{kim_chang_kadla_2008, title={Polyoxometalate (POM) oxidation of lignin model compounds}, volume={62}, ISSN={["0018-3830"]}, DOI={10.1515/HF.2008.006}, abstractNote={Abstract}, number={1}, journal={HOLZFORSCHUNG}, author={Kim, Yong Sik and Chang, Hou-min and Kadla, John F.}, year={2008}, pages={38–49} }
 @article{kadla_jameel_2008, title={Professor Hou-Min Chang 2007 ISWFPC Notable Achievement Award}, volume={28}, ISSN={["0277-3813"]}, DOI={10.1080/02773810802124753}, number={2}, journal={JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY}, author={Kadla, John F. and Jameel, Hasan}, year={2008}, pages={67–68} }
 @article{holtman_chang_kadla_2007, title={An NMR comparison of the whole lignin from milled wood, MWL, and REL dissolved by the DMSO/NMI procedure}, volume={27}, ISSN={["1532-2319"]}, DOI={10.1080/02773810701700828}, abstractNote={Abstract Lignins isolated from pine milled wood, milled wood lignin (MWL), and residual enzyme lignin (REL) were compared using modified thioacidolysis, modified DFRC, gel permeation chromatography (GPC), two‐dimensional Heteronuclear Multiple Quantum Coherence (HMQC) NMR, and quantitative 13C NMR. Dissolution of the lignin for solution‐state NMR was accomplished by utilizing the recently reported DMSO/N‐methylimidazole/acetic anhydride solvent system. Contrary to previous reports, comparison of the lignin preparations by thioacidolysis indicated that REL was more structurally similar to the lignin in the milled wood and Wiley wood meal than MWL. Total monomer yields indicated that the MWL was lower in β‐aryl ether content than the other preparations, and this was verified by quantitative 13C NMR. NMR analysis indicated that the inter‐unit linkages present in all the lignin preparations are consistent with the present knowledge about lignin biosynthesis. The contribution of minor end group structures in the MWL are further decreased in the milled wood, indicating that they are preferentially isolated as low molecular weight material, possibly generated during the milling process. All other structural moieties were similar in all preparations. GPC data indicated that the milled wood and REL both contain a portion of lignin with a molecular weight of 55,000 g/mol. Data indicate that the inefficiency of the DFRC method may be related to molecular mobility or accessibility in higher molecular weight portions of the lignin polymer.}, number={3-4}, journal={JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY}, author={Holtman, Kevin M. and Chang, Hou-Min and Kadla, John F.}, year={2007}, pages={179–200} }
 @article{kim_chang_kadla_2007, title={Polyoxometalate (POM) oxidation of milled wood lignin (MWL)}, volume={27}, ISSN={["0277-3813"]}, DOI={10.1080/02773810701702188}, abstractNote={Abstract The chemical structural changes of Lodgepole pine milled wood lignin (MWL) before and after polyoxometalate (POM) oxidation were investigated using gel permeation chromatography (GPC), Fourier Transform infrared spectroscopy (FTIR), and solution‐state nuclear magnetic resonance spectroscopy (NMR). 13C NMR spectroscopic data revealed an approximately 28% decrease in α‐OH/β‐O‐4 inter‐unit linkages after POM treatment. This was accompanied by an increase in carbonyl and phenolic hydroxyl content. These results suggest POM oxidation involved side chain (such as α‐OH/β‐O‐4) oxidation and/or degradation of some of the inter‐unit linkages. Quantitative 13C NMR along with GPC analysis revealed an increase in the degree of condensation of the MWL as a result of POM treatment, suggesting radical coupling as a major reaction pathway.}, number={3-4}, journal={JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY}, author={Kim, Yong Sik and Chang, Hou-min and Kadla, John F.}, year={2007}, pages={225–241} }
 @article{mao_holtman_scott_kadla_schmidt-rohr_2006, title={Differences between lignin in unprocessed wood, milled wood, mutant wood, and extracted lignin detected by C-13 solid-state NMR}, volume={54}, ISSN={["1520-5118"]}, DOI={10.1021/jf062199q}, abstractNote={Solid-state 13C nuclear magnetic resonance (NMR) spectroscopy was applied to intact and isolated loblolly pine wood samples to identify potential structural changes induced by tree age, milling, lignin extraction, or naturally occurring mutations. Special attention was paid to ketone and aldehyde as well as nonpolar alkyl groups, which could be observed at low concentrations (<2 in 1000 C) using improved spinning-sideband suppression with gated decoupling. Carbonyl structures were present in intact wood, and there are more keto groups than aldehydes. Their concentrations increased from juvenile to mature wood and with milling time, whereas extraction did not alter the C=O fraction. Significant amounts of aldehyde and dihydroconiferyl alcohol residues were present in coniferyl aldehyde dehydrogenase-deficient wood, confirming solution-state NMR spectra of the corresponding lignin. These results demonstrate the utility of solid-state NMR as an assay for changes in the lignin structure of genetically modified plants.}, number={26}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Mao, Jingdong and Holtman, Kevin M. and Scott, Jay T. and Kadla, John F. and Schmidt-Rohr, Klaus}, year={2006}, month={Dec}, pages={9677–9686} }
 @article{hu_yeh_chang_matsumoto_kadla_2006, title={Elucidation of the structure of cellulolytic enzyme lignin}, volume={60}, ISSN={["1437-434X"]}, DOI={10.1515/HF.2006.061}, abstractNote={Abstract}, number={4}, journal={HOLZFORSCHUNG}, author={Hu, Zhoujian and Yeh, Ting-Feng and Chang, Hou-min and Matsumoto, Yuji and Kadla, John F.}, year={2006}, month={Jul}, pages={389–397} }
 @article{sykes_li_isik_kadla_chang_2006, title={Genetic variation and genotype by environment interactions of juvenile wood chemical properties in Pinus taeda L.}, volume={63}, ISSN={["1286-4560"]}, DOI={10.1051/forest:2006073}, abstractNote={Genetic variation and genotype by environment interaction (G×E) were studied in several juvenile wood traits of 11 year-old loblolly pine trees (Pinus taeda L.). Wafer thin (200 µm) samples from juvenile (ring 3) and transition (ring 8) wood of 12 mm increment cores were analyzed. Transition wood had higher α-cellulose content (46.1%), longer fiber (1.98 mm), and higher coarseness (0.34), but lower lignin (29.7%) than juvenile wood (cellulose 40.9%, fiber length 1.4 mm, coarseness 0.28 and lignin 30.3%). General combining ability variance for the traits explained 2% to 10% of the total variance, whereas the specific combining ability variance was negligible, except for α-cellulose content in transition wood (2%). Specific combining ability by site interaction variance explained from 5% (fiber length) to 37% (lignin) of the total variance. Weak individual-tree heritabilities were found for all the traits, except coarseness, which was moderately high in both juvenile (0.39) and transition wood (0.30). Full-sib and half-sib family heritabilities of traits ranged 0.29 to 0.72. Genetic correlations of wood quality traits with volume and stem straightness were weak, while favorable genetic correlations of lignin with cellulose, coarseness and fiber length were observed. Implications on forest tree improvement programs were discussed. heritability / genetic correlation / α-cellulose / coarseness / lignin}, number={8}, journal={ANNALS OF FOREST SCIENCE}, publisher={EDP Sciences}, author={Sykes, Robert and Li, Bailian and Isik, Fikret and Kadla, John and Chang, H. -M.}, year={2006}, month={Dec}, pages={897–904} }
 @article{berlin_balakshin_gilkes_kadla_maximenko_kubo_saddler_2006, title={Inhibition of cellulase, xylanase and beta-glucosidase activities by softwood lignin preparations}, volume={125}, ISSN={["0168-1656"]}, DOI={10.1016/j.jbiotec.2006.02.021}, abstractNote={The conversion of lignocellulosic biomass to fuel ethanol typically involves a disruptive pretreatment process followed by enzyme-catalyzed hydrolysis of the cellulose and hemicellulose components to fermentable sugars. Attempts to improve process economics include protein engineering of cellulases, xylanases and related hydrolases to improve their specific activity or stability. However, it is recognized that enzyme performance is reduced during lignocellulose hydrolysis by interaction with lignin or lignin-carbohydrate complex (LCC), so the selection or engineering of enzymes with reduced lignin interaction offers an alternative means of enzyme improvement. This study examines the inhibition of seven cellulase preparations, three xylanase preparations and a beta-glucosidase preparation by two purified, particulate lignin preparations derived from softwood using an organosolv pretreatment process followed by enzymatic hydrolysis. The two lignin preparations had similar particle sizes and surface areas but differed significantly in other physical properties and in their chemical compositions determined by a 2D correlation HSQC NMR technique and quantitative 13C NMR spectroscopy. The various cellulases differed by up to 3.5-fold in their inhibition by lignin, while the xylanases showed less variability (< or = 1.7-fold). Of all the enzymes tested, beta-glucosidase was least affected by lignin.}, number={2}, journal={JOURNAL OF BIOTECHNOLOGY}, author={Berlin, Alex and Balakshin, Mikhail and Gilkes, Neil and Kadla, John and Maximenko, Vera and Kubo, Satoshi and Saddler, Jack}, year={2006}, month={Sep}, pages={198–209} }
 @article{svenson_jameel_chang_kadla_2006, title={Inorganic reactions in chlorine dioxide bleaching of softwood kraft pulp}, volume={26}, ISSN={["0277-3813"]}, DOI={10.1080/02773810601023255}, abstractNote={Abstract A softwood kraft pulp (27 kappa) was bleached with chlorine dioxide to various end pH values. The formation of chlorite, chlorate, and chloride was measured to quantify the amount of chlorine dioxide wasted as a function of pH during a Do (pre‐bleaching) stage. Chlorate formation increased with a decrease in final pH. Conversely, residual chlorite increased with an increase in the final pH. After 120 min of bleaching the total residual chlorite and chlorate showed that no substantial increase in residual oxidant occurs when bleaching to an end pH below 3.4. As a result, the brightness and permanganate numbers for low pH chlorine dioxide bleached pulps did not differ when bleaching to an end pH between 3.4 and 1.8. However, decreasing the pH below 3.4 did result in increased organic chloride formation. The results are contrary to previous studies where the maximum bleaching efficiency for a D1 stage was reported to occur when the end pH was between 3 and 4.}, number={3}, journal={JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY}, author={Svenson, Douglas R. and Jameel, Hasan and Chang, Hou-min and Kadla, John F.}, year={2006}, pages={201–213} }
 @article{yeh_braun_goldfarb_chang_kadla_2006, title={Morphological and chemical variations between juvenile wood, mature wood, and compression wood of loblolly pine (Pinus taeda L.)}, volume={60}, ISSN={["1437-434X"]}, DOI={10.1515/HF.2006.001}, abstractNote={Abstract}, number={1}, journal={HOLZFORSCHUNG}, author={Yeh, TF and Braun, JL and Goldfarb, B and Chang, HM and Kadla, JF}, year={2006}, month={Jan}, pages={1–8} }
 @article{yeh_morris_goldfarb_chang_kadla_2006, title={Utilization of polar metabolite profiling in the comparison of juvenile wood and compression wood in loblolly pine (Pinus taeda)}, volume={26}, ISSN={["0829-318X"]}, DOI={10.1093/treephys/26.11.1497}, abstractNote={Juvenile wood (JW) of conifers is often associated with compression wood (CW), with which it is sometimes believed to be identical. To determine whether JW and CW can be distinguished metabolically, we compared gas chromatographic profiles of 25 polar metabolites from rooted cuttings of a single loblolly pine (Pinus taeda L.) clone raised in controlled environment chambers and subject to three treatments: (1) grown erect with minimal wind sway (control); (2) swayed by wind from oscillating fans; and (3) with 30-cm growth increments successively bent at an angle of 45 degrees to the vertical. Profiles were compared by principal component analysis. Substantial increases in abundances of coniferin and p-glucocoumaryl alcohol separated immature JW-forming xylem tissues of the control trees from the CW-forming xylem of the bent and swayed trees.}, number={11}, journal={TREE PHYSIOLOGY}, author={Yeh, Ting-Feng and Morris, Cameron R. and Goldfarb, Barry and Chang, Hou-Min and Kadla, John F.}, year={2006}, month={Nov}, pages={1497–1503} }
 @article{balakshin_capanema_goldfarb_frampton_kadla_2005, title={NMR studies on Fraser fir Abies fraseri (Pursh) Poir. Lignins (vol 59, 488, 2005)}, volume={59}, ISSN={["1437-434X"]}, DOI={10.1515/hf.2005.112}, abstractNote={Abstracting & Indexing}, number={6}, journal={HOLZFORSCHUNG}, author={Balakshin, MY and Capanema, EA and Goldfarb, B and Frampton, J and Kadla, JF}, year={2005}, pages={706–706} }
 @article{sykes_li_hodge_goldfarb_kadla_chang_2005, title={Prediction of loblolly pine wood properties using transmittance near-infrared spectroscopy}, volume={35}, ISSN={["1208-6037"]}, DOI={10.1139/X05-161}, abstractNote={ Near-infrared (NIR) spectroscopy is a rapid nondestructive technique that has been used to characterize chemical and physical properties of a wide range of materials. In this study, transmittance NIR spectra from thin wood wafers cut from increment cores were used to develop calibration models for the estimation of α-cellulose content, average fiber length, fiber coarseness, and lignin content in the laboratory. Eleven-year-old trees from two sites were sampled using 12-mm increment cores. Earlywood and latewood of ring 3 and ring 8 from these samples were analyzed in the laboratory using microanalytical methods for α-cellulose content, average fiber length, fiber coarseness, and lignin content. NIR calibrations and laboratory measurements based on one site were generally reliable, with coefficients of determination (R2) ranging from 0.54 to 0.88 for average fiber length and α-cellulose content, respectively. Predicting ring 8 properties using ring 3 calibration equations showed potential for predicting α-cellulose content and fiber coarseness, with R2 values of approximately 0.60, indicating the potential for early selection. Predicting the wood properties using the calibration equations from one site to predict another showed moderate success for α-cellulose content (R2 = 0.64) and fiber coarseness (R2 = 0.63), but predictions for fiber length were relatively poor (R2 = 0.43). Prediction of lignin content using transmittance NIR spectroscopy was not as reliable in this study, partially because of low variation in lignin content in these wood samples and large errors in measuring lignin content in the laboratory. }, number={10}, journal={CANADIAN JOURNAL OF FOREST RESEARCH}, author={Sykes, R and Li, BL and Hodge, G and Goldfarb, B and Kadla, J and Chang, HM}, year={2005}, month={Oct}, pages={2423–2431} }
 @article{svenson_chang_jameel_kadla_2005, title={The role of non-phenolic lignin in chlorate-forming reactions during chlorine dioxide bleaching of softwood kraft pulp}, volume={59}, ISSN={["1437-434X"]}, DOI={10.1515/HF.2005.017}, abstractNote={Abstract}, number={2}, journal={HOLZFORSCHUNG}, author={Svenson, DR and Chang, HM and Jameel, H and Kadla, JF}, year={2005}, pages={110–115} }
 @inproceedings{morris_goldfarb_isik_li_chang_sederoff_kadla_2005, title={Variation of a-cellulose content and related metabolites during wood formation in loblolly pine}, volume={13}, booktitle={13th ISWFPC Proceedings}, author={Morris, C. R. and Goldfarb, B. and Isik, F. and Li, C. S. and Chang, H.-M. and Sederoff, R. and Kadla, J. F.}, year={2005} }
 @article{capanema_balakshin_kadla_2004, title={A comprehensive approach for quantitative lignin characterization by NMR spectroscopy}, volume={52}, ISSN={["1520-5118"]}, DOI={10.1021/jf035282b}, abstractNote={A detailed approach for the quantification of different lignin structures in milled wood lignin (MWL) has been suggested using a combination of NMR techniques. 1H-13C heteronuclear multiple quantum coherence and quantitative 13C NMR of nonacetylated and acetylated spruce MWL have been found to have a synergetic effect, resulting in significant progress in the characterization of lignin moieties by NMR. About 80% of side chain moieties, such as different beta-O-4, dibenzodioxocin, phenylcoumaran, pinoresinol, and others, have been identified on the structural level. The presence of appreciable amounts of alpha-O-alkyl and gamma-O-alkyl ethers has been suggested. Although the quantification of various condensed moieties was less precise than for side chain structures, reliable information can be obtained. Comparison of the calculated results with known databases on spruce MWL structure shows that the suggested approach is rather informative and comparable with the information obtained from the combination of various wet chemistry methods. Discrepancies between the results obtained in this study and those previously published are discussed.}, number={7}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Capanema, EA and Balakshin, MY and Kadla, JF}, year={2004}, month={Apr}, pages={1850–1860} }
 @article{lemeune_jameel_chang_kadla_2004, title={Effects of ozone and chlorine dioxide on the chemical properties of cellulose fibers}, volume={93}, ISSN={["1097-4628"]}, DOI={10.1002/app.20509}, abstractNote={Abstract}, number={3}, journal={JOURNAL OF APPLIED POLYMER SCIENCE}, author={Lemeune, S and Jameel, H and Chang, HM and Kadla, JF}, year={2004}, month={Aug}, pages={1219–1223} }
 @article{sykes_isik_li_kadla_chang_2004, title={Genetic variation in physiochemical wood properties in loblolly pine (Pinus taeda L.)}, volume={2}, number={12}, journal={TAPPI Journal}, author={Sykes, R. and Isik, F. and Li, B. and Kadla, J. and Chang, H.-M.}, year={2004}, pages={3–8} }
 @article{kadla_kubo_2004, title={Lignin-based polymer blends: analysis of intermolecular interactions in lignin-synthetic polymer blends}, volume={35}, ISSN={["1878-5840"]}, DOI={10.1016/j.compositesa.2003.09.019}, abstractNote={The development of lignin-based thermoplastics relies on altering the viscoelastic properties of lignin through chemical modification or polymer blending. In polymer blends, miscibility is dependent on the occurrence of exothermic reactions such as hydrogen-bonding, acid–base interactions and the like. The effects of polymer–polymer interactions, specifically hydrogen-bonding, on lignin-based thermoplastics was studied in a series of lignin/synthetic polymer blends prepared by melt extrusion. Thermal analysis revealed miscible blend behavior in the lignin blends containing PEO and PET, whereas the PVA and PP lignin blends appeared immiscible. The glass transition (Tg) of the lignin/PEO and lignin/PET blends showed a negative deviation from a linear mixing rule, indicative of specific intermolecular interactions. DRFT-IR analysis revealed the formation of a strong intermolecular hydrogen bond between lignin and PEO, but not with PET.}, number={3}, journal={COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING}, author={Kadla, JF and Kubo, S}, year={2004}, pages={395–400} }
 @article{yokoyama_chang_reiner_atalla_weinstock_kadla_2004, title={Polyoxometalate oxidation of nonphenolic lignin subunits in water: Effect of substrate structure on reaction kinetics}, volume={58}, ISSN={["1437-434X"]}, DOI={10.1515/HF.2004.016}, abstractNote={Summary}, number={2}, journal={HOLZFORSCHUNG}, author={Yokoyama, T and Chang, HM and Reiner, RS and Atalla, RH and Weinstock, IA and Kadla, JF}, year={2004}, pages={116–121} }
 @book{kadla_gilbert_venditti_kubo_2004, place={Washington, DC}, title={Porous fibers from natural/synthetic polymer blends}, volume={6,765,028}, number={2004 July 20US6765028B2}, institution={U.S. Patent and Trademark Office}, author={Kadla, J. F. and Gilbert, R. D. and Venditti, R. A. and Kubo, S.}, year={2004}, month={Jul} }
 @article{holtman_chang_kadla_2004, title={Solution-state nuclear magnetic resonance study of the similarities between milled wood lignin and cellulolytic enzyme lignin}, volume={52}, ISSN={["1520-5118"]}, DOI={10.1021/jf035084k}, abstractNote={The structures of milled wood lignin (MWL) and cellulolytic enzyme lignin (CEL) have been analyzed using traditional chemical methods and solution-state NMR techniques. Comparisons of the results obtained reveal that subtle differences exist between the two lignin preparations. Thioacidolysis produced higher monomer yields from CEL than MWL, suggesting MWL has a more condensed structure. Quantitative (13)C NMR determined the degree of condensation in MWL to be 0.43 unit per aromatic moiety as compared to 0.36 in CEL. The MWL also contained a lower amount of beta-O-4' substructures per aromatic ring than CEL, 0.41 versus 0.47, respectively. Carbohydrate analysis revealed that the MWL may contain a higher proportion of middle lamella material as compared to the CEL. Because the middle lamella is considered to have a more condensed lignin structure, on the basis of the bulk polymerization theory, these results could explain the differences in beta-O-4' and degree of condensation.}, number={4}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Holtman, KM and Chang, HM and Kadla, JF}, year={2004}, month={Feb}, pages={720–726} }
 @article{dai_gilbert_kadla_2004, title={Synthesis, characterization, and mesophase formation of phenylacetoxy cellulose and its halogenated derivatives}, volume={5}, ISSN={["1526-4602"]}, DOI={10.1021/bm034245q}, abstractNote={A series of phenylacetoxy cellulosics with degrees of substitution (DS) between 1.4 and 3.0 and different halogenation (2-chloro, 3-chloro, 4-chloro, 2,4-dichloro, 3,4-dichloro, and 4-bromo) were synthesized. All the prepared phenylacetoxy cellulosics were soluble in dimethylformamide (DMF) and DMAc. The solubility increased with increasing DS. Mesophases were observed for all of the phenylacetoxy cellulosics with low to medium DS (DS < 2.5) in DMF and DMAc. Non- or mono-halogeneated phenylacetoxy cellulosics with high DS (DS > 1.9) were soluble in methylene chloride (CH2Cl2), whereas those with very low DS or di-halogenation on the phenyl ring were only slightly swollen or partially soluble in CH2Cl2. Non- and mono-halogenated phenylacetoxy cellulosics were soluble in DMSO and formed liquid crystals regardless of the DS, in contrast to CH2Cl2 solutions which display liquid crystalline behavior at medium to high DS (DS > 1.9) only. The solubility of the di-halogenated phenylacetoxy cellulosics in DMSO was limited to approximately 40 wt %.}, number={1}, journal={BIOMACROMOLECULES}, author={Dai, QZ and Gilbert, RD and Kadla, JF}, year={2004}, pages={74–80} }
 @inproceedings{yu_capanema_batista_josserand_johnson_nelson_mckeand_mackay_kadla_li_et al._2004, title={Tracking down the effects of a rare mutant gene in loblolly pine: a first report}, booktitle={2004 Paper Summit, Spring Technical and International Environmental Conference}, publisher={CD-ROM published by TAPPI,  Norcross, GA}, author={Yu, Q. and Capanema, E. and Batista, V. B. and Josserand, S. and Johnson, G. and Nelson, C. D. and McKeand, S. E. and MacKay, J. J. and Kadla, J. F. and Li, B. and et al.}, year={2004} }
 @article{zhu_chang_kadla_2003, title={A new method for the preparation of peroxymonophosphoric acid}, volume={81}, ISSN={["1480-3291"]}, DOI={10.1139/V03-010}, abstractNote={ A new method for the preparation of peroxymonophosphoric acid (H3PO5) has been developed. It utilizes a biphasic solution to moderate the vigorous reaction between phosphorous pentoxide (P2O5) and hydrogen peroxide (H2O2). P2O5 is suspended in carbon tetrachloride (CCl4), and concentrated H2O2 is slowly added while being vigorously stirred at low temperature. Careful control of the reaction temperature through the slow addition of H2O2 is critical. Using typical preparation conditions (P2O5:H2O2 = 0.5:1, H2O2 70 wt %, 2°C, 120–180 min), ~70% of the H2O2 is effectively converted to H3PO5. Increasing the concentration of H2O2, as well as the mole ratio of P2O5:H2O2, leads to an even higher % conversion of H2O2 to H3PO5. The addition of glacial acetic acid to the P2O5:H2O2 suspension at the end of the 120–180 min reaction (P2O5:H2O2:CH3COOH = 0.5:1:0.3) leads to the formation of peracetic acid in addition to H3PO5, and to an overall increase in the conversion ratio of total peroxy acids based on H2O2 (>95%).Key words: peroxymonophosphoric acid, synthesis, stability, conversion ratio. }, number={2}, journal={CANADIAN JOURNAL OF CHEMISTRY}, author={Zhu, T and Chang, HM and Kadla, JF}, year={2003}, month={Feb}, pages={156–160} }
 @article{stasolla_scott_egertsdotter_kadla_d o'malley_sederoff_zyl_2003, title={Analysis of lignin produced by cinnamyl alcohol dehydrogenase-deficient Pinus taeda cultured cells}, volume={41}, ISSN={["0981-9428"]}, DOI={10.1016/S0981-9428(03)00051-2}, abstractNote={Comparative studies were conducted on composition of lignin produced both in vivo and in vitro by cinnamyl alcohol dehydrogenase (CAD)-deficient mutant loblolly pine (Pinus taeda L.). In vivo studies were performed using differentiating xylem obtained from two genotypes of heterozygous (CAD/cad) and two genotypes of homozygous (cad/cad) CAD-deficient mutant trees. In vitro studies were performed using a culture system in which cells, generated from the same genotypes, were induced to produce lignin in culture. Steady state RNA levels and enzyme activity of CAD were dramatically reduced in both xylem and cultured cells obtained from homozygous mutant trees, compared to their heterozygous counterparts. Light microscopic studies showed pronounced differences during the lignin formation between homozygous and heterozygous cells. Phenolic compounds in the heterozygous (CAD/cad) cells were deposited around the cell wall, accumulated preferentially in vacuoles of the homozygous (cad/cad) cells. Differences in lignin composition as revealed by thioacidolysis were also observed. Lignin of both xylem tissue and cultured cells obtained from CAD-deficient homozygotes showed lower levels of coniferyl alcohols and significant enrichments in dihydroconiferyl alcohol (DHCA) and coniferyl aldehyde, compared to their heterozygous counterparts. The striking similarities in lignin composition observed both in vivo and in vitro, open new possibilities for the use of culture systems aimed at revealing the mechanisms controlling lignin biosynthesis, and the formation of DHCA subunits.}, number={5}, journal={PLANT PHYSIOLOGY AND BIOCHEMISTRY}, author={Stasolla, C and Scott, J and Egertsdotter, U and Kadla, J and D O'Malley and Sederoff, R and Zyl, L}, year={2003}, month={May}, pages={439–445} }
 @article{holtman_chang_jameel_kadla_2003, title={Elucidation of lignin structure through degradative methods: Comparison of modified DFRC and thioacidolysis}, volume={51}, ISSN={["0021-8561"]}, DOI={10.1021/jf0340411}, abstractNote={Milled wood and milled wood lignin (MWL) samples were subjected to DFRC and thioacidolysis. Despite the fact that both methods selectively cleave aryl ether bonds, substantial differences in results were obtained. Lignin thioacidolysis gave total molar yields of degradation monomer products in the range of 3.5-7 mol % higher than DFRC. GPC analysis showed that the thioacidolysis-treated lignin was degraded to a lower average molecular weight than that treated by DFRC. Contrary to results reported for lignin model compounds, these results indicate that the DFRC method does not completely or efficiently degrade the lignin polymer. In fact, the DFRC-degraded lignin retained much of the characteristics of the original MWL. Elemental analysis revealed the presence of bromine in the DFRC-treated lignin, and two-dimensional (1)H-(13)C HMQC NMR spectroscopy showed the presence of beta-O-4 linkages in the DFRC-treated lignin. No beta-O-4 interunit linkages were detected in the thioacidolysis-treated lignin. These results are consistent with the lower monomer yields and the higher average molecular weight of the DFRC-treated lignin and indicate inefficiency in the chemistry of the method, probably due to steric constraints of the polymeric nature of lignin.}, number={12}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Holtman, KM and Chang, HM and Jameel, H and Kadla, JF}, year={2003}, month={Jun}, pages={3535–3540} }
 @article{sykes_isik_li_kadla_chang_2003, title={Genetic variation of juvenile wood properties in a loblolly pine progeny test}, volume={2}, number={12}, journal={TAPPI Journal}, author={Sykes, R. and Isik, F. and Li, B. L. and Kadla, J. and Chang, H. M.}, year={2003}, pages={08-} }
 @article{sykes_isik_li_kadla_chang_2003, title={Genetic variation of juvenile wood properties in loblolly pine diallel test}, volume={27}, journal={Proc. 27th Biennial Southern Forest Tree Improvement Conference}, author={Sykes, R. and Isik, F. and Li, B. and Kadla, J. and Chang, H-M.}, year={2003}, pages={27} }
 @article{kadla_kubo_2003, title={Miscibility and hydrogen bonding in blends of poly(ethylene oxide) and kraft lignin}, volume={36}, DOI={10.1021/ma0348371d}, number={20}, journal={Macromolecules}, author={Kadla, J. F. and Kubo, S.}, year={2003}, pages={7803–7811} }
 @article{zhu_kadla_chang_jameel_2003, title={Reactions of lignin with peroxymonophosphoric acid: The degradation of lignin model compounds}, volume={57}, ISSN={["0018-3830"]}, DOI={10.1515/HF.2003.007}, abstractNote={Summary}, number={1}, journal={HOLZFORSCHUNG}, author={Zhu, T and Kadla, JF and Chang, HM and Jameel, H}, year={2003}, pages={44–51} }
 @article{kubo_kadla_2003, title={The formation of strong intermolecular interactions in immiscible blends of poly(vinyl alcohol) (PVA) and lignin}, volume={4}, ISSN={["1526-4602"]}, DOI={10.1021/bm025727p}, abstractNote={The intermolecular interactions of lignin with a hydrophilic polymer, poly(vinyl alcohol) (PVA), were studied using thermal analyses and FT-IR spectroscopy of a series of PVA/hardwood kraft lignin blend fibers prepared by thermal extrusion. Although two phases are observed in this blend system, some of the lignin was closely associated with the PVA in the PVA-rich phase. The crystallinity of the PVA fraction was reduced with increasing lignin content. An interaction energy density of -9.34 cal cm(-1), calculated from melting point depression data, suggests that strong intermolecular interactions exist between PVA and lignin. FT-IR analysis indicates the formation of strong intermolecular hydrogen bonds between the hydroxyl groups of PVA and lignin. Although the PVA/lignin blend system is immiscible in the bulk, the results herein show the existence of some specific intermolecular interaction between PVA and lignin.}, number={3}, journal={BIOMACROMOLECULES}, author={Kubo, S and Kadla, JF}, year={2003}, pages={561–567} }
 @article{kishimoto_kadla_chang_jameel_2003, title={The reactions of lignin model compounds with hydrogen peroxide at low pH}, volume={57}, ISSN={["1437-434X"]}, DOI={10.1515/HF.2003.008}, abstractNote={Summary}, number={1}, journal={HOLZFORSCHUNG}, author={Kishimoto, T and Kadla, JF and Chang, HM and Jameel, H}, year={2003}, pages={52–58} }
 @article{svenson_kadla_chang_jameel_2002, title={Effect of pH on the inorganic species involved in a chlorine dioxide reaction system}, volume={41}, DOI={10.1021/ie020191}, number={24}, journal={Industrial & Engineering Chemistry Research}, author={Svenson, D. R. and Kadla, J. F. and Chang, H. M. and Jameel, H.}, year={2002}, pages={5927–5933} }
 @article{svenson_kadla_chang_jameel_2002, title={Effect of pH on the mechanism of OClO center dot oxidation of aromatic compounds}, volume={80}, ISSN={["0008-4042"]}, DOI={10.1139/V02-089}, abstractNote={ Contrary to previous reports, the reaction mechanism of chlorine dioxide (OClO·) with benzyl alcohols involves both radical cation and benzyl radical mechanisms dependent on pH. The primary reaction product between OClO· and 1-(3,4-dimethoxy-phenyl) ethanol at pH 8 is 3,4-dimethoxyacetophenone. At pH 4 no acetophenone was observed; the majority of the degradation products were chlorinated and aromatic ring-oxidized compounds. A primary kinetic isotope effect (kH/kD = 2.05) was observed in the reaction of OClO· with 1-(3,4-dimethoxy-phenyl)-(1-2H) ethanol at pH 8, but was absent at pH 4 (kH/kD [Formula: see text] 1). Similarly, the corresponding methyl ether (4-(1-methoxy)ethyl-1,2-dimethoxybenzene) was substantially less reactive at pH > 6. On the basis of these results, competing pH-dependent reaction mechanisms have been proposed, where at high pH OClO· reacts with benzyl alcohols via a OClO·–benzyl alcohol complex.Key words: chlorine dioxide, mechanism, kinetic isotope effect, aromatic radical cation, benzyl radical. }, number={7}, journal={CANADIAN JOURNAL OF CHEMISTRY-REVUE CANADIENNE DE CHIMIE}, author={Svenson, D and Kadla, JF and Chang, HM and Jameel, H}, year={2002}, month={Jul}, pages={761–766} }
 @article{kadla_kubo_venditti_gilbert_compere_griffith_2002, title={Lignin-based carbon fibers for composite fiber applications}, volume={40}, ISSN={0008-6223}, url={http://dx.doi.org/10.1016/S0008-6223(02)00248-8}, DOI={10.1016/S0008-6223(02)00248-8}, abstractNote={Carbon fibers have been produced for the first time from a commercially available kraft lignin, without any chemical modification, by thermal spinning followed by carbonization. A fusible lignin with excellent spinnability to form a fine filament was produced with a thermal pretreatment under vacuum. Blending the lignin with poly(ethylene oxide) (PEO) further facilitated fiber spinning, but at PEO levels greater than 5%, the blends could not be stabilized without the individual fibers fusing together. Carbon fibers produced had an over-all yield of 45%. The tensile strength and modulus increased with decreasing fiber diameter, and are comparable to those of much smaller diameter carbon fibers produced from phenolated exploded lignins. In view of the mechanical properties, tensile 400–550 MPa and modulus 30–60 GPa, kraft lignin should be further investigated as a precursor for general grade carbon fibers.}, number={15}, journal={Carbon}, publisher={Elsevier BV}, author={Kadla, J.F and Kubo, S and Venditti, R.A and Gilbert, R.D and Compere, A.L and Griffith, W}, year={2002}, pages={2913–2920} }
 @article{yokoyama_kadla_chang_2002, title={Microanalytical method for the characterization of fiber components and morphology of woody plants}, volume={50}, ISSN={["0021-8561"]}, DOI={10.1021/jf011173q}, abstractNote={Microanalytical techniques were developed which allow the rapid characterization of fiber components and morphology of loblolly pine in a large number of samples. These techniques consist of extractives removal, holocellulose preparation, alpha-cellulose and lignin content determination, and fiber length and coarseness analyses. Greater than 95% of the nonvolatile extractives from an increment core sample of loblolly pine was removed by four successive two-day acetone extractions. Fiber morphology and alpha-cellulose content was determined from holocellulose prepared from only 100 mg of wood. Similarly, a microanalytical acetyl bromide method was developed that enabled the accurate determination of lignin content from less than 50 mg of wood. Through the development of these microanlytical methods, it is possible to accurately and rapidly analyze fiber morphology and chemical components in a large number of increment core samples.}, number={5}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Yokoyama, T and Kadla, JF and Chang, HM}, year={2002}, month={Feb}, pages={1040–1044} }
 @article{kadla_kubo_venditti_gilbert_2002, title={Novel hollow core fibers prepared from lignin polypropylene blends}, volume={85}, ISSN={["0021-8995"]}, DOI={10.1002/app.10640}, abstractNote={Polymer blending is a convenient method to develop products with desirable properties. The chemical and physical properties of the polymer blends are dependent on monomer type(s), molecular weight, and distribution of the respective polymers. 1 Most polymers are immiscible due to a low entropy of mixing.1-3 Only through specific intermolecular interactions can favorable polymer blending occur and composite materials with desirable properties be produced. Nonetheless, a large number of technologically interesting polymers are multiphase inhomogeneous materials.4 Properties such as prevention and control of gas and liquid permeation, gas and liquid adsorption/desorption and transmission, and reflection of light are dependent on phase behavior, and more specifically on the size of the domains within the material. Lignin, second only to cellulose in natural abundance, is an amorphous natural polymer existing in the cell wall of plants. 5 Its utilization in solid material systems is constrained by the extensive crosslinking, strong intramolecular interactions, and high molecular weight of most lignins, which upon heating decompose rather than soften and flow. However, through polymer blending6-13 or lignin derivatization13-19 these interactions are disrupted, thus altering the lignin's viscoelastic properties and allowing for flow. Recently, we have developed lignin fibers for carbon fiber applications through thermal spinning of lignin-synthetic polymer blends. 20 Through careful control of processing conditions, miscible continuous fibers are produced.21 However, fibers with core-shell morphology can be formed through manipulation of processing conditions and/or blend composition. The premise behind this method for the production of porous hollow-core lignin fibers is based on the differences in thermal stabilities of polymers (Scheme 1).22 This method uses selected polymers with different thermal stabilities, i.e., one tends to crosslink at high temperatures while the other one melts and flows from within the fiber. If the affinities of the two polymers are weak enough, they will form an immiscible two phase material. Thermal treatment will produce pores because of the melting or pyrolysis of the low melting polymer. At high levels of the low melting polymer, hollow fibers may be formed. Controlling the structure of the polymer blends will provide a way to obtain fibers with tailored porous hollow core morphology. Production of porous hollow-core fibers from the thermal treatment of immiscible polymer blended fibers containing a meltable polymer and a thermally stable polymer. In this study we have selected a commercial technical lignin and polypropylene as the thermally stable polymer and thermally unstable one, respectively. Here we report a preliminary study on the porous hollow-core fibers produced from this method. Hardwood Kraft lignin, HWKL (Indulin® AT—Westvaco Corp.) was desalted and thermally processed prior to fiber blending using a previously published method, 20 and mechanically blended with polypropylene (PP, syndiotactic, M̄w ∼127,000, Aldrich). The blend ratios were set at 87.5/12.5, 75/25, 50/50 (HWKL/PP) by weight. Control fibers were made with no PP and no lignin. The samples were then extruded in an Atlas mixer/extruder with a 1/32-inch spinneret to produce fine fibers. The optimal temperatures for fiber production were obtained by slowly increasing the temperature until fiber formation occurred. Fiber spinning was then performed isothermally at that temperature. The spinning temperature is closely related to the molten viscosity of the sample; a low spinning temperature is indicative of a low molten viscosity. The spinning temperature was 220°C for the HWKL and did not change with increasing PP content. Phase immiscibility in the lignin-PP blend is shown in Figure 1, in which a melting point (Tm) and glass transition point (Tg) of the PP phase and a Tg of the lignin phase are distinctly observed at all ratios of lignin/PP. Further, the Tg of the lignin and PP phases appear independent of the lignin/PP ratio, further indicating negligible mixing of the two polymers. Differential scanning calorimetry profiles of lignin-PP fibers of varying lignin/PP ratios. The spun fibers were heated to 250°C to remove the polypropylene and induce crosslinking of the lignin phase. Upon heating, the PP flowed from the fiber and was visually observed to pool outside of the fiber. Fiber stability was dependent on heating rate and PP blend content. Increasing the heating rate above 1.5°C min−1 resulted in the fibers in contact with one another fusing together. As the temperature increased at a heating rate below 1.5°C min−1 the Tg of the lignin increases faster than the temperature, maintaining the material in the glassy state (Tg > T): nontacky. At heating rates above 1.5°C min−1, the crosslinking reactions are not able to maintain Tg > T, and the material devitrifies entering the liquid rubbery state, tacky, and thus fuse together. Gillham and coworkers have described such phenomena in continuous heating transformation (CHT) diagrams. 23 Thus, the thermoplastic character of the lignin is changed to thermosetting, enabling the lignin fibers to maintain fiber form while the PP is removed. Figure 2 shows the HWKL/PP (75/25) fibers before (green fibers) and after (crosslinked fibers) thermal treatment. Stretching of the green fibers (magnified inset) reveals the polypropylene phase as distinct “strings” dispersed throughout the lignin fiber. In the corresponding thermally treated fibers the removal of the polypropylene phase(s) produces the observed porous microstructure. Scanning electron micrographs of HWKL/PP (75/25) fibers. The fiber to the left is prior to thermal treatment. It has been stretched to produce fractures along the fiber. The inset shows the “stringy” polypropylene phase dispersed throughout the lignin phase at a point of fracture. The fiber to the right is after thermal treatment. It has been cut at a 30° angle with respect to the fiber axis to show the extent of the porous structure and the hollow-core nature of the fiber. In this article, we described the production of porous hollow fibers made from a wood-based biopolymer and a recyclable petrochemical polymer. It is expected that these fibers relative to solid lignin fibers will have high specific surface area and a high flexural strength/mass ratio due to the lignin shell/hollow core morphology. We are now studying the effect of the mixing ratio, molecular weight and temperature on the dispersion of PP in the lignin matrix, and the relation of the initial dispersion and the pore size distribution in the final product fibers. Production of activated porous carbon fibers is also a current subject and research is underway. The authors would like to thank Oak Ridge National Laboratories and NC State University for the financial support. SEM photographs were courtesy of Oak Ridge National Laboratories.}, number={6}, journal={JOURNAL OF APPLIED POLYMER SCIENCE}, author={Kadla, JF and Kubo, S and Venditti, RA and Gilbert, RD}, year={2002}, month={Aug}, pages={1353–1355} }
 @article{dimmel_mackay_courchene_kadla_scott_dm o'malley_mckeand_2002, title={Pulping and bleaching of partially CAD-deficient wood}, volume={22}, ISSN={["0277-3813"]}, DOI={10.1081/WCT-120016260}, abstractNote={ABSTRACT Mutant loblolly pine trees that are partially deficient in cinnamyl alcohol dehydrogenase (CAD) have been studied as a possible new source of pulpwood. Young (4- and 6-year-old) partially CAD-deficient pine trees are ˜20% more easily delignified (pulping and bleaching) and provide similar pulp yields to that of similarly aged normal pines grown on the same plots. Bleached pulp from a 6-year-old partially CAD-deficient pine tree displayed better strength properties than the same age normal pine tree; this probably reflects the milder pulping conditions needed in the case of the partially CAD-deficient tree. Studies also were conducted on a limited number of 14-year-old trees from a different genetic background. In contrast to the results with young trees, no real differences in ease of delignification, pulp yields, bleached pulp strength properties, and wood specific gravities were observed with the 14-year-old trees. There would likely be no penalty if partially CAD-deficient trees were used for lumber products. The rapid growth of partially CAD-deficient trees could make them a valuable pulpwood.}, number={4}, journal={JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY}, author={Dimmel, DR and MacKay, JJ and Courchene, CE and Kadla, JF and Scott, JT and DM O'Malley and McKeand, SE}, year={2002}, pages={235–248} }
 @article{kadla_chang_2002, title={Reactions of lignin with cyanamide activated hydrogen peroxide Part 3. The degradation of pine kraft lignin}, volume={56}, ISSN={["1437-434X"]}, DOI={10.1515/HF.2002.013}, abstractNote={Summary}, number={1}, journal={HOLZFORSCHUNG}, author={Kadla, JF and Chang, HM}, year={2002}, pages={76–84} }
 @article{stauffer_venditti_gilbert_kadla_2002, title={Removing paraffin-based wax coatings from old corrugated containers using supercritical carbon dioxide}, volume={83}, ISSN={0021-8995 1097-4628}, url={http://dx.doi.org/10.1002/app.10248}, DOI={10.1002/app.10248}, abstractNote={Abstract}, number={12}, journal={Journal of Applied Polymer Science}, publisher={Wiley}, author={Stauffer, Thad C. and Venditti, Richard A. and Gilbert, Richard D. and Kadla, John F.}, year={2002}, month={Jan}, pages={2699–2704} }
 @article{ikeda_holtman_kadla_chang_jameel_2002, title={Studies on the effect of ball milling on lignin structure using a modified DFRC method}, volume={50}, ISSN={["0021-8561"]}, DOI={10.1021/jf010870f}, abstractNote={The structures of milled wood lignin (MWL), cellulolytic enzyme lignin (CEL), and residual lignin (REL) from a loblolly pine were analyzed using a modified derivatization followed by reductive cleavage (DFRC) method developed to allow the quantitative determination of three different structural monomeric products originating in lignin: phenolic beta-O-4, alpha-O-4, and etherified beta-O-4 structures. Results show that MWL and CEL are structurally identical, with an increased phenolic beta-O-4 content compared to that of the original Wiley milled wood. These results indicate that the portion of lignin linked to carbohydrates and that not linked to carbohydrates are structurally the same. Modified DFRC analysis of the effect of ball milling on the structure of lignin in wood, MWL, CEL, and REL indicate that vibratory ball milling does not change the lignin structure provided certain precautions are taken. Specifically, dry vibratory ball milling under a nitrogen atmosphere causes substantial structural changes including condensation, whereas vibratory ball milling in toluene had little effect on the lignin structure. This indicates that the structural differences observed in MWL and CEL arise because of the extraction procedure, which preferentially extracts phenolic lignin structures. MWL and CEL are representative of the total lignin in wood; however, due primarily to the solvent extraction process, higher phenolic hydroxyl contents are observed. Nitrobenzene oxidation showed structural results similar to those from the modified DFRC method.}, number={1}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Ikeda, T and Holtman, K and Kadla, JF and Chang, HM and Jameel, H}, year={2002}, month={Jan}, pages={129–135} }
 @inproceedings{o'malley_scott_harkins_kadia_mckeand_chang_2001, title={Cinnamyl alcohol dehydrogenase (cad) and genomic approaches to manipulating wood properties in loblolly pine}, booktitle={7th Brazilian Symposium on the Chemistry of Lignins and Other Wood Components}, author={O'Malley, D. and Scott, J. and Harkins, D. and Kadia, J. and McKeand, S. and Chang, H-M}, year={2001}, pages={19–24} }
 @article{stauffer_venditti_gilbert_kadla_chernyak_montero_2001, title={Supercritical carbon dioxide dewaxing of old corrugated containers}, volume={81}, ISSN={["0021-8995"]}, DOI={10.1002/app.1533}, abstractNote={Abstract}, number={5}, journal={JOURNAL OF APPLIED POLYMER SCIENCE}, author={Stauffer, TC and Venditti, RA and Gilbert, RD and Kadla, JF and Chernyak, Y and Montero, GA}, year={2001}, month={Aug}, pages={1107–1114} }
 @article{bunyard_kadla_desimone_2001, title={Viscosity effects on the thermal decomposition of bis(perfluoro-2-N-propoxypropionyl) peroxide in dense carbon dioxide and fluorinated solvents}, volume={123}, ISSN={["0002-7863"]}, DOI={10.1021/ja0103344}, abstractNote={The thermal decomposition of the free-radical initiator bis(perfluoro-2-N-propoxyprionyl) peroxide (BPPP) was studied in dense carbon dioxide and a series of fluorinated solvents. For the fluorinated solvents, the observed first-order decomposition rate constants, k(obs), increased with decreasing solvent viscosity, suggesting a single-bond decomposition mechanism. The k(obs) values are comparatively larger in dense carbon dioxide and similar to the "zero-viscosity" rate constants extrapolated from the decomposition kinetics in the fluorinated solvents. The decomposition activation parameters demonstrate a compensation behavior of the activation enthalpy with the activation entropy upon change in solvent viscosity. Comparison of the change in activation parameter values upon change in solvent viscosity for BPPP with two additional initiators, acetyl peroxide (AP) and trifluoroacetyl peroxide (TFAP), further suggests that carbon dioxide exerts a very minimal influence on the decomposition mechanism of these initiators through solvent-cage effects.}, number={30}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Bunyard, WC and Kadla, JF and DeSimone, JM}, year={2001}, month={Aug}, pages={7199–7206} }
 @article{kadla_gilbert_2000, title={Cellulose structure: A review}, volume={34}, number={3-4}, journal={Cellulose Chemistry and Technology}, author={Kadla, J. F. and Gilbert, R. D.}, year={2000}, pages={197–216} }
 @inbook{gilbert_kadla_1999, title={Polysaccharides-cellulose in biopolymers from renewable resources}, booktitle={Biopolymers from renewable resources}, publisher={New York: Springer-Verlag}, author={Gilbert, R. D. and Kadla, J. F.}, year={1999}, pages={47–90} }
 @article{kadla_chang_jameel_1999, title={The reactions of lignins with high temperature hydrogen peroxide - Part 2. The oxidation of kraft lignin}, volume={53}, ISSN={["0018-3830"]}, DOI={10.1515/HF.1999.047}, abstractNote={Summary}, number={3}, journal={HOLZFORSCHUNG}, author={Kadla, JF and Chang, HM and Jameel, H}, year={1999}, pages={277–284} }
 @article{kadla_cornman_1998, title={An EPR investigation into the reactions of alkaline hydrogen peroxide with cyanamide}, ISSN={["0300-9580"]}, DOI={10.1039/a801251b}, abstractNote={Free-radical involvement in an alkaline hydrogen peroxide/cyanamide system has been demonstrated using electron paramagnetic resonance (EPR) spectroscopy. A stable free radical is formed which shows coupling to two pairs of equivalent 14N nuclei (a14N1 = 7.30, a14N2 = 2.13 G). Both hydroxyl and carbon-centered radicals have been trapped with 5,5-dimethyl-4,5-dihydro-3H-pyrrole N-oxide (DMPO) (DMPO–OH: aH = aN = 14.9 G, DMPO–C: aH = 24.0, aN = 16.4 G). The presence of HOO˙ has been inferred based on the absence of reactivity in the presence of superoxide dismutase. Involvement of superoxide and cyanamide radicals has been demonstrated by the formation of ring-opened and cyanamide coupled products obtained from reactions of alkaline hydrogen peroxide–cyanamide with substituted aromatic compounds.}, number={10}, journal={JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2}, author={Kadla, JF and Cornman, CR}, year={1998}, month={Oct}, pages={2309–2313} }
 @article{kadla_chang_chen_gratzl_1998, title={Reactions of lignin with cyanamide activated hydrogen peroxide Part 1. The degradation of lignin model compounds}, volume={52}, ISSN={["1437-434X"]}, DOI={10.1515/hfsg.1998.52.5.506}, abstractNote={Monomeric lignin model compounds representing various functional groups found in residual lignins were reacted with cyanamide activated hydrogen peroxide. Non-phenolic lignin model compounds failed to react even under extreme reaction conditions (90°C), while phenolic lignin model compounds underwent rapid oxidation. Reaction optimization studies reveal that these reactions are strongly dependent on pH and the cyanamide-to-peroxide ratio, while temperature is not a factor. Through the use of electron paramagnetic resonance (EPR) spectroscopy free radical involvement has been demonstrated. In contrast to previous literature, a predominately free-radical mechanism exists, and on the basis of the reactions carried out in the presence of superoxide dismutase, the presence of .O 2 - has been determined.}, number={5}, journal={HOLZFORSCHUNG}, author={Kadla, JF and Chang, PM and Chen, CL and Gratzl, JS}, year={1998}, pages={506–512} }
 @article{kadla_chang_chen_gratzl_1998, title={Reactions of lignin with cyanamide activated hydrogen peroxide Part 2. The degradation mechanism of phenolic lignin model compounds}, volume={52}, ISSN={["0018-3830"]}, DOI={10.1515/hfsg.1998.52.5.513}, abstractNote={The reactions of monomeric phenolic lignin model compounds with cyanamide activated hydrogen peroxide were studied. Analyses of the various reaction products indicate four main reactions occur : aromatic hydroxylation, demethoxylation, radical coupling and oxidative ring opening. The predominate products from apocynol and acetoguaiacone were dicarboxylic acid compounds, maleic/fumaric, oxalic and succinic acid derivatives, consistent with degradation by superoxide. In the degradation of creosol, 3-hydroxy-4-methoxy-6-methyl-N-methylaniline was the major compound isolated, providing evidence of a cyanamide radical. Finally, plausible pathways to the formation of superoxide anion and cyanamide oxidation products from alkaline hydrogen peroxide and cyanamide are proposed and their impact on delignification is discussed.}, number={5}, journal={HOLZFORSCHUNG}, author={Kadla, JF and Chang, HM and Chen, CL and Gratzl, JS}, year={1998}, pages={513–520} }
 @article{kadla_chang_jameel_1997, title={The reactions of lignins with hydrogen peroxide at high temperature .1. The oxidation of lignin model compounds}, volume={51}, ISSN={["0018-3830"]}, DOI={10.1515/hfsg.1997.51.5.428}, abstractNote={This work deals with hydrogen peroxide bleaching at high temperature (90°) using simple phenolic and non-phenolic model compounds of the benzyl alcohol and benzaldehyde types. In addition to the reactions of the phenolic representatives, proceeding via the well known Dakin and Dakin-like mechanisms, the non-phenolic compounds are shown to react at these higher temperatures via an S N 2 mechanism to give ultimately the corresponding benzoic acids and a dimeric ether compound.}, number={5}, journal={HOLZFORSCHUNG}, author={Kadla, JF and Chang, HM and Jameel, H}, year={1997}, pages={428–434} }