bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sonochemical deposition of silver nanoparticles on wool fibers
Authors: Hadad Liraz , Perkas Nina , Gofer Yosef , Calderon‐Moreno Jose , Ghule Anil , Gedanken Aharon 
Published: February 2007

AbstractSilver nanoparticles were deposited on the surface of natural wool with the aid of powered ultrasound. The average particle size was 5–10 nm, but larger aggregates of 50–100 nm were also observed. The sonochemical irradiation of a slurry containing wool fibers, silver nitrate, and ammonia in an aqueous medium for 120 min under an argon atmosphere yielded a silver–wool nanocomposite. By varying the gas and reaction conditions, we could achieve control over the deposition of the metallic silver particles on the surface of the wool fibers. The resulting silver‐deposited wool samples were characterized with X‐ray diffraction, transmission electron microscopy, high‐resolution transmission electron microscopy, high‐resolution scanning electron microscopy, electron‐dispersive X‐ray analysis, Brunauer, Emmett, and Teller physical adsorption method, X‐ray photoelectron spectroscopy, and Raman and diffused reflection optical spectroscopy. The results showed that the strong adhesion of the silver to the wool was a result of the adsorption and interaction of silver with sulfur moieties related to the cysteine group. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1732–1737, 2007
Antimicrobial activity of cotton fabrics containing immobilized enzymes
Authors: Ibrahim N. A. , Gouda M. , El‐shafei A. M. , Abdel‐Fatah O. M. 
Published: February 2007

AbstractImmobilization of α‐amylase, alkaline pectinase, and laccase enzymes onto ester‐crosslinked as well as Cu‐chelated cotton fabrics were carried out. Factors affecting the extent of enzyme‐loading and retention activities of immobilized enzymes were studied. Proper conditions for attaining higher extent of fixation along with better retained activity were studied. The degree of antimicrobial activity of treated fabric samples against gram‐negative and gram‐positive bacteria, filamentous, and nonfilamentous fungi were evaluated. The antimicrobial activity is determined by the type of substrate, i.e., Cu‐chelated > ester‐crosslinked and activated cotton substrate, and the nature of immobilized enzyme, i.e., alkaline pectinase > α‐amylase > laccase, irrespective of the used microorganism. The antimicrobial activities of the treated fabrics are completely maintained after laundering at least ten consecutive wash cycles. Further consecutive wash cycles, i.e., 20 or 30 cycles, has practically negative impact on the retained antimicrobial efficacy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1754–1761, 2007
Comparison of the kinetics of conventional and microwave methyl methacrylate polymerization
Authors: Jovanovic Jelena , Adnadjevic Borivoj 
Published: February 2007

AbstractA comparative investigation of the conventional and microwaves kinetics of methyl methacrylate (MMA) polymerization was performed. A method for determining the increase of the reaction rate in the microwave field (β) was presented. It was found that at all of the investigated temperatures and powers the polymerization rates increased in the presence of microwave energy by up to 8.9 times compared with conventional polymerization. Isothermal kinetics of the conventional MMA polymerization was investigated and its parameters were determined using isoconversion method. It was found that the calculated kinetics parameters changes complexly with degree of MMA conversion (α) and are in the mutual linear functional relationship, which is so called “compensation effect.” The complex changes of the kinetics parameters with α are explained with the postulated model for the mechanism of the MMA polymerization. The kinetics of the MMA polymerization under the microwave field (MWF) with different input power was investigated and its parameters were determined on the basis of the conversion‐temperature curves and Arrhenius equation. The values of the kinetics parameters for MMA polymerization in the MWF are dependent on α and are from 1.2 to 12 times lower than that for conventional MMA polymerization. A new method for the determination of activation energy (Ea) of the investigated process in the MWF was described. Decreased Ea value of the polymerization process in the MWF compared with the conventional polymerization is explained with the formation of the nonequilibrium energetic distribution of the reactants due to the rapid transfer of energy in the reaction system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1775–1782, 2007
Application of enzymatically gelled chitosan solutions to water‐resistant adhesives
Authors: Yamada Kazunori , Aoki Toshihiro , Ikeda Naoya , Hirata Mitsuo 
Published: February 2007

AbstractAn investigation was undertaken on the application of dilute chitosan solutions gelled by tyrosinase‐catalyzed reaction with 3,4‐dihydroxyphenethylamine (dopamine). The tyrosinase‐catalyzed reaction with dopamine conferred water‐resistant adhesive properties to the semidilute chitosan solutions. The viscosity of the chitosan solutions increased highly by the tyrosinase‐catalyzed reaction and the subsequent reactions between o‐quinone compounds and chitosan. These highly viscous, gel‐like modified chitosan materials were allowed to spread onto the surfaces of the glass slides, which were tightly lapped together and held them in water. Tensile shear adhesive strength of over 400 kPa was observed for the modified chitosan samples. The increase in the amino group concentration of the chitosan solutions and the molecular mass of the chitosan used effectively led to the increase in adhesive strength of the glass slides. In addition, in the case where the chitosan solution was gelled by the enzymatic reaction with dopamine in the presence of poly(ethylene glycol), adhesive strength sharply increased at shorter reaction times concomitantly with the increase in the viscosity of the chitosan solutions because the tyrosinase activity effectively was retained by poly(ethylene glycol). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1818–1827, 2007
Microencapsulation of intumescent flame‐retardant agent: Application to flame‐retardant natural rubber composite
Authors: Wang Jincheng , Chen Yuehui 
Published: February 2007

AbstractThe first part of this investigation focused on the synthesis and characterization of a microencapsulated intumescent flame retardant (MIFR) agent. Two steps were used in the synthesis process. The structure was characterized by scanning electron microscopy, thermogravimetric anaylysis, and Fourier transform infrared spectroscopy. The addition of this MIFR agent into natural rubber (NR) led to an improvement in its physicomechanical and flame‐retardant (FR) properties. The second part focused on the evaluation of such characteristics as cure characteristics, FR property, tensile properties, abrasion resistance, and dynamic mechanical analysis of MIFR filled NR composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1828–1838, 2007
Synthesis and characterization of ethylene vinyl acetate/Mg–Al layered double hydroxide nanocomposites
Authors: Kuila T. , Acharya H. , Srivastava S. K. , Bhowmick A. K. 
Published: February 2007

AbstractMg–Al layered double hydroxide (LDH)/Ethylene vinyl acetate (EVA‐28) nanocomposites were prepared through solution intercalation method using organically modified layered double hydroxide (DS‐LDH). DS‐LDH was made by the intercalation of sodium dodecyl sulfate (SDS) ion. The structure of DS‐LDH and its nanocomposites with EVA‐28 was determined by X‐ray diffraction (XRD) and transmission electron microscope (TEM) analysis. XRD analysis shows that the original peak of DS‐LDH shifted to lower 2θ range and supports the formation of intercalated nanocomposites while, TEM micrograph shows the presence of partially exfoliated LDH nanolayers in addition to orderly stacked LDH crystallites in the polymer matrix. The presence of LDH in the nanocomposites has been confirmed by Fourier transform infrared (FTIR) analysis. The mechanical properties show significant improvement for the nanocomposite with respect to neat EVA‐28. Thermogravimetric (TGA) analysis shows that thermal stability of the nanocomposites is higher than that of EVA‐28. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1845–1851, 2007
Synthesis, characterization, and properties of poly(vinyl acetate)‐ and poly(vinyl alcohol)‐grafted chitosan
Authors: Radhakumary C. , Nair Prabha D. , Mathew Suresh , Reghunadhan Nair C. P. 
Published: February 2007

AbstractGraft copolymers of chitosan and vinyl acetate were synthesized by free radical technique using cerium (IV) as the initiator. Under controlled conditions, as much as 92% grafting with a grafting yield of 30–40% could be achieved. Chitosan‐g‐poly(vinyl alcohol) copolymers were derived by the alkaline hydrolysis of the chitosan‐g‐poly(vinyl acetate) precursor. Thermogravimetric, FTIR, and X‐ray diffraction analyses of chitosan and the copolymers confirmed the grafting reaction between chitosan and vinyl acetate and also the subsequent hydrolysis. Both the copolymers possessed very good film‐forming properties. Grafting resulted in a significant increase in mechanical strength of both the copolymers in the dry condition. Chitosan‐g‐poly(vinyl acetate) (CH‐PVAc) proved more hydrophobic than did pure chitosan, whereas chitosan‐g‐poly(vinyl alcohol) (CH‐PVOH) exhibited enhanced hydrophilicity as evident from their swelling characteristics and contact angle measurements. The enhanced swelling of CH‐PVOH was ascribed to the presence of the pendant poly(vinyl alcohol) group. At pH 1.98, the CH‐PVAc copolymer films showed greater stability than do pure chitosan films, which is highly beneficial for specific biomedical applications. Both the copolymers showed lower glass transition temperature than do pure chitosan. Grafting did not affect the overall thermal stability, and the differential thermogram substantiated the grafting. The investigations indicate that the synthetic–natural hybrid copolymers having desirable mechanical properties and tailored hydrophilic/hydrophobic characteristics are realizable. These polymers could be exploited for varied biomedical applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1852–1859, 2007
Chiral separation of D,L‐serine racemate using a molecularly imprinted polymer composite membrane
Authors: Son Seung‐Hee , Jegal Jonggeon 
Published: February 2007

AbstractMolecularly imprinted (MIP) composite membranes were prepared using conventional interfacial polymerization technique that has been often used for the preparation of reverse osmosis (RO) membrane. Target molecules (D‐serine) were used together with the piperazine (PIP) and Trimesoyl chloride (TMC) for the interfacial polymerization of the active layer with chiral spaces in it on the surface of the polysulfone ultrafiltration membranes. After formation of the polyamide composite membranes, the target molecules in the active layers were removed and MIP composite membranes were prepared. The MIP membranes prepared so were then characterized with analytical methods and proved to be effective for the selective permeation of D‐serine. When serine racemate was used for optical resolution, the diffusion rate of the D‐serine appeared to be faster than that of the L‐serine and in permeates, the concentration of the D‐serine increased with operation time. When the operating time reached 60 h, enantiomeric excess (% ee) of the serine mixture in permeates became about 80%. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1866–1872, 2007
Preparation of granular crosslinkable medium‐density polyethylene
Authors: Madani Mohammad , Sharifi‐Sanjani Naser , Rezaei‐Zare Ehsan , Faridi‐Majidi Reza 
Published: February 2007

AbstractGranular crosslinkable medium‐density polyethylene (XLPE) without scorch inhibitor was prepared adding organic peroxide [2, 5‐dimethyl‐ 2, 5‐ di‐ (t‐butyl‐peroxy) hexyne‐3] through extrution process, in industrial scale. Twin screw extruder was used to mix the polyethylene and the peroxide. The temperature zones of the extruder were controlled very carefully to prevent unwanted crosslinking during extrusion. Compression molding, rotational molding, and injection molding of XLPE at 155°C made no crosslinking in PE, and then they were exposed to higher temperatures at which the organic peroxide decomposed to provide free radicals which led to the crosslinking of the MDPE. The thermal properties (using dynamic mechanical analysis, DMA, differential scanning calorimetric analysis, DSC, and thermogravimetric analysis, TGA, techniques) and mechanical properties (including strain at break and stress at break) of virgin PE, crosslinkable PE, and crosslinked PE have been compared. The crossliked PE and virgin PE were also studied by X‐ray diffraction (XRD) technique. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1873–1879, 2007
Dispersion and mechanical properties of polypropylene/multiwall carbon nanotubes composites obtained via dynamic packing injection molding
Authors: Xiao Yan , Zhang Xiaoqing , Cao Wen , Wang Ke , Tan Hong , Zhang Qin , Du Rongni , Fu Qiang 
Published: February 2007

AbstractIn this article, polypropylene (PP)/multiwall carbon nanotubes (MWNTs) composites were prepared through dynamic packing injection molding, in which the oscillatory shear was exerted on the molten composite during packing and solidification stage of injection‐molding. A simultaneous increase of tensile strength and impact strength has been achieved for PP/MWNTs composites containing only 0.6 wt % MWNTs. Particularly, the impact strength was found increased by almost 50% at such low MWNTs content. These improvements in properties were attributed to uniform dispersion and possible orientation of nanotube induced by shear stress. It was suggested that the dynamic packing injection molding could provide much strong shear force for better dispersion of MWNTs in PP matrix, on one hand, but breakdown the aspect ratio of MWNTs, on the other. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1880–1886, 2007
Characterization and aging of biotreated kraft bagasse pulp
Authors: Adel Abeer M. 
Published: February 2007

AbstractStrains of bacteria [Pseudomonas flurescens (Pf1 and Pf2); Bacillus subtilis (B)] were used for treatment of kraft bagasse pulp. Both of the bacterial treated kraft bagasse pulp (BKBP) and control (C) pulp samples were chelated with EDTA and then bleached with hydrogen peroxide. The effect of aging on paper brightness was investigated. The brightness change due to aging for both control sample and bleached bacterial treated (BBKBP) pulp are 19.38% and (5.99%–15.35%), respectively. The crystallinity index (CrI) is calculated for both control sample (C) and BBKBP via X‐ray diffraction patterns. It was found that the CrI for BBKBP was increased by 4.46% compared with the control (C) sample. The relative intensity and assignment of absorption bands for BKBP) were studied via FTIR spectra. Pyrolytic behavior of the different samples was investigated by thermal gravimetric analysis and derivative thermogravimetric techniques. Calculations of the mass loss were used to elucidate the rate constant of decomposition and the activation energy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1887–1894, 2007
PCL/poloxamer 188 blend microsphere for paclitaxel delivery: Influence of poloxamer 188 on morphology and drug release
Authors: Ma Guilei , Song Cunxian 
Published: February 2007

AbstractA novel controlled release system, paclitaxel‐loaded poly (ε‐caprolactone) (PCL)/poloxamer 188 (Pluronic F68, F68) blend microspheres is proposed in the present work. F68 was incorporated into PCL matrices as both a pore‐forming agent and a drug releasing enhancer. Paclitaxel‐loaded PCL/F68 blend microspheres with different amounts of F68 were prepared by the oil‐in water (O/W) emulsion/solvent evaporation method. Characterization of the microspheres followed to examine the particle size, the drug encapsulation efficiency, the surface morphology, and in vitro release behavior. The influences of F68 on microsphere morphology and paclitaxel release are discussed. The porosity of the surface of PCL/F68 blend microspheres and the release rate of paclitaxel from the PCL/F68 blend microspheres increased as the initial amount of blended F68 increased. Faster and controlled release was achieved in comparison with the PCL microspheres. Through this study, the developed microporous PCL/F68 blend microspheres could be used as a drug delivery system to enhance and control drug release in the future. © 2007 Wiley Periodicals, Inc. JAppl Polym Sci 104: 1895–1899, 2007
Grafting poly(t‐butyl acrylate) to poly(allylamine) by inverse microemulsion radical polymerization: From comb‐polymer to amphiphilic shell crosslinked polymer nanocapsule
Authors: Sarkar Debanjan , El Khoury Jouliana M. , Lopina Stephanie T. , Hu Jun 
Published: February 2007

AbstractAn interfacial grafting radical polymerization method for amphiphilic comb copolymer and shell crosslinked polymer nanocapsules was reported. Macropolyradicals on a water soluble long chain polyamine were generated with hydrogen peroxide in the water phase and subsequent grafting radical polymerization of a vinylic monomer at the water/oil interface proceeded at 65°C. In the presence of a crosslinker, the resulting graft copolymer formed a defined core‐shell structure with hydrophilic aqueous core functionalized by the polyamine and a hydrophobic crosslinked polymer shell. The structure of the core‐shell material was characterized by NMR, FTIR, DSC, TGA, SEM, TEM, and the mechanism of the graft polymerization is proposed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1905–1911, 2007
Thermal, mechanical, and dielectric behaviors of crosslinked linear low density polyethylene/polyolefin elastomers blends
Authors: Ke Qing Quan , Huang Xing Yi , Wei Ping , Wang Gen Lin , Jiang Ping Kai 
Published: February 2007

AbstractCrosslinked linear low density polyethylene (XLPE) containing polyolefin elastomers (POE) has been evaluated. The blends with different dicumyl peroxide (DCP) and POE contents have been prepared and processed by compression molding. A series of the samples obtained have been investigated by gel content determination, scanning electron microscopy (SEM), different scanning calorimetry (DSC), mechanical, and dielectric behaviors measurements. The results obtained clearly show the relevant influence of the POE content, as well as of the DCP content, which tends to enhance crosslinking. As expected, the toughness of XLPE is improved by using adequate content of POE, and the blends exhibit a much more similar tensile behavior to that of elastomer. In addition, the results indicate that the blends possess the excellent dielectric behaviors, such as dielectric constant and dissipation factor. The crystallinity of the blends decreases as the DCP and POE contents increase. The melting temperature of the blends also decreases with the increase of DCP content, while POE content has few influences on the melting temperature of the blends. The SEM images strongly reveal that the blends are partially compatible, and the POE can be dispersed well in the matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1920–1927, 2007
Controlled‐release formulations for hydroxy urea and rifampicin using polyphosphate‐anion‐crosslinked chitosan microspheres
Authors: Gupta K. C. , Jabrail Fawzi Habeeb 
Published: February 2007

AbstractPhysically crosslinked microspheres for the controlled delivery of rifampicin and hydroxy urea have been prepared with sodium tripolyphosphate (STPP) and sodium hexametaphosphate (SHMP) anion crosslinkers. Chitosan with a constant degree of deacetylation (75 wt %) and a constant molecular weight (1134 kg/mol) has been found to be useful for the controlled release of selected drugs. The microspheres prepared with the SHMP anion crosslinker are more hydrophobic and compact in their shape and size than the microspheres prepared with the STPP anion crosslinker. The SHMP‐anion‐crosslinked microspheres show optimum loading at pH 3, whereas the STPP‐anion‐crosslinked microspheres show optimum loading at pH 4. The STPP‐anion‐crosslinked microspheres are suitable for the controlled release of rifampicin, but the SHMP‐anion‐crosslinked microspheres are suitable for the controlled release of hydroxy urea. The drug‐release characteristics of the physically crosslinked chitosan microspheres are explained with respect to their size and the ionic interactions of the encapsulated drugs with the polymer matrices and anion crosslinkers. The initial burst release of the loaded drugs is Fickian in nature and follows first‐order kinetics, but the controlled step of the drug release shows a non‐Fickian nature and follows zero‐order kinetics. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1942–1956, 2007
A new map of mangroves for Kakadu National Park, Northern Australia, based on stereo aerial photography
Authors: Mitchell Anthea L. , Lucas Richard M. , Donnelly Brian E. , Pfitzner Kirrilly , Milne Anthony K. , Finlayson Max 
Published: February 2007

Abstract
Using colour aerial photography, a set of fine (∼1 m) spatial resolution orthomosaics and accompanying Digital Elevation Models (DEMs) were generated for the majority of mangroves in Kakadu National Park, Northern Australia, from which their extent and canopy height have been mapped.
The orthomosaics and DEMs, which were based on 68 stereo pairs acquired in 1991, cover an area of approximately 742 km2 and a coastal distance of 86 km. The DEMs have a height resolution of approximately ± 1 m.
The entire mosaic represents a key historical baseline data set of the extent and height of mangroves within the Park against which to observe and quantify changes in response to, for example, sea‐level rise.
The data sets will be available to assist management of the coastal environment and also to provide a unique insight into the distribution, dynamics and condition of mangroves. The techniques used are applicable to mangroves and other forested wetlands in other regions of Australia and elsewhere.

Copyright © 2007 John Wiley & Sons, Ltd.
Nonhuman anthropoid primate femoral neck trabecular architecture and its relationship to locomotor mode
Authors: Fajardo Roberto J. , Müller Ralph , Ketcham Rich A. , Colbert Matthew 
Published: February 2007

AbstractFunctional analyses of human and nonhuman anthropoid primate femoral neck structure have largely ignored the trabecular bone. We tested hypotheses regarding differences in the relative distribution and structural anisotropy of trabecular bone in the femoral neck of quadrupedal and climbing/suspensory anthropoids. We used high‐resolution X‐ray computed tomography to analyze quantitatively the femoral neck trabecular structure of Ateles geoffroyi, Symphalangus syndactylus, Alouatta seniculus, Colobus guereza, Macaca fascicularis, and Papio cynocephalus (n = 46). We analyzed a size‐scaled superior and inferior volume of interest (VOI) in the femoral neck. The ratio of the superior to inferior VOI bone volume fraction indicated that the distribution of trabecular bone was inferiorly skewed in most (but not all) quadrupeds and evenly distributed the climbing/suspensory species, but interspecific comparisons indicated that all taxa overlapped in these measurements. Degree of anisotropy values were generally higher in the inferior VOI of all species and the results for the two climbing/suspensory taxa, A. geoffroyi (1.71 ± 0.30) and S. syndactylus (1.55 ± 0.04), were similar to the results for the quadrupedal anthropoids, C. guereza (male = 1.64 ± 0.13; female = 1.68 ± 0.07) and P. cynocephalus (1.47 ± 0.13). These results suggest strong trabecular architecture similarity across body sizes, anthropoid phylogenetic backgrounds, and locomotor mode. This structural similarity might be explained by greater similarity in anthropoid hip joint loading mechanics than previously considered. It is likely that our current models of anthropoid hip joint mechanics are overly simplistic. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.