bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of glycidyl methacrylate containing diethanol amine and its binary copolymers with ethyl methacrylate and butyl methacrylate as nano‐size chelating resins for removal of heavy metal ions
Authors: Abd El‐Ghaffar M. A. , El‐Halawany N. R. , Ahmed S. A. 
Published: November 2009

AbstractOne of the most important applications of chelating and functional polymers is their capability to recover metal ions from their solutions. This study concerns the synthesis of a hydrophilic glycidyl methacrylate (GMA) monomer‐bearing diethanol amine (DEA) chelating group from the reaction of GMA and DEA. The formed adduct (A) was characterized via FTIR and mass spectra and subjected to homopolymerization and binary copolymerization with ethyl methacrylate and butyl methacrylate. The copolymerization process was carried out via a semi‐batch emulsion polymerization technique by using potassium persulphate/sodium bisulphite as a redox pair initiation system and sodium dodecyl benzene sulphonate as an emulsifier at 65°C. The obtained polymers were characterized via FTIR, thermal gravimetric analysis, and UV–VIS. Volume‐average diameters (Dv) in nanoscale range for the prepared polymers were confirmed by transmission electron microscope investigation. It was shown that the obtained nano‐size chelating polymers have a powerful adsorption character toward transition metal ions (Cu+2, Cr+3, Ni+2, and Co+2) and efficient selectivity for Cu+2 and Ni+2 ions at normal pH. The effects of pH, time, and different comonomer feed compositions on the uptake of metal ions were studied. The reaction between the obtained chelating resins and different metal ions was confirmed to be a second‐order reaction. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Biodegradable polyurethane elastomers prepared from isocyanate‐terminated poly(ethylene adipate), castor oil, and glycerol
Authors: Teramoto Naozumi , Saitoh Yuichi , Takahashi Atsuo , Shibata Mitsuhiro 
Published: November 2009

AbstractThe curing reaction of tolylene‐2,4‐diisocyanate‐terminated poly(ethylene adipate) (PEA‐TDI) with a mixture of castor oil (CO) and glycerol (GO) with a NCO/OH ratio of 1.0 at 150°C gave crosslinked polyurethane (CO/GO‐PU). All the polyurethanes were elastomeric materials at room temperature. The glass‐transition temperature of the CO/GO‐PU increased with decreasing CO/GO ratio. All the cured polyurethanes had a higher 5% weight loss temperature than PEA‐TDI. The tensile strength and modulus of the polyurethanes increased with decreasing CO/GO ratio, and tensile residual strain after 300% elongation for all the CO/GO‐PUs was almost 0. All the polyurethanes had biodegradability, when measured by a biochemical oxygen demand method in an aqueous medium using activated sludge. The rate of the biodegradation of the polyurethanes increased with an increase of CO/GO ratio. The crosslinked CO‐PU showed much higher biodegradability than the linear PEA‐TDI. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and characterization of pH‐ and salt‐responsive hydrogels based on etherificated sodium alginate
Authors: Lin Hailin , Zhou Jinjin , Yingde Cui , Gunasekaran Sundaram 
Published: November 2009

AbstractHydrogels composed of etherificated sodium alginate (ESA), sodium acrylic acid (NaAA), and poly (vinyl alcohol) (PVA) were synthesized by aqueous solution polymerization. The effects of reaction variables such as terminal pH, ions, and ionic strength on hydrogel swelling ratio (SR) were determined and compared. SR was influenced strongly by pH and ionic strength. SR increased with increasing pH but tended to decrease with PVA content. At a given ionic strength, SR of ESA/NaAA/PVA hydrogel was dependent on the valence of anion; SR was higher in multivalent anion salt solution than in monovalent anion salt solution, i.e., SRK2SO4 > SRKCl and SRNa2SO4 > SRNaCl. The swelling kinetic of the hydrogels showed Fickian kinetic diffusion in acidic media and non‐Fickian behavior in alkaline media. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Reactivity ratios and copolymer composition evolution during styrene/dimethacrylate free‐radical crosslinking copolymerization
Authors: Schroeder Walter F. , Aranguren Mirta I. , Borrajo Julio 
Published: November 2009

AbstractIn this article, experimental and simulated results are presented for the evolution of the copolymer composition as unsaturations are consumed in the free‐radical cross‐linking copolymerization of Styrene(St) and BisphenolA glycerolate dimethacrylate (BDMA). Real time FTIR measurements were performed to monitor the depletion of each comonomer double bond during the isothermal curing reaction at 80°C. From the experimental data corresponding to different feed compositions, the initial reactivity ratios and their evolution with conversion were determined via a nonlinear least squares optimization of the integrated form of the copolymerization equation. The reactivity ratio of St increases continuously and exponentially with the overall reaction conversion, while that of BDMA decreases linearly. A modified terminal copolymerization model including the dependence of the reactivity ratios with the overall conversion was proposed. The application of this model provides a consistent fitting for the conversion of each comonomer during all reaction stages, even at high conversion values where large diffusion and topological restrictions for chain movements are present. Simulations show that the concentration of styrene units added to the copolymer increases with the overall reaction conversion, while that for the BDMA double bonds diminishes. Structures rich in homopolymerized styrene are predicted at later stages of the reaction.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Highly crosslinked micron‐sized, monodispersed polystyrene particles by semicontinuous dispersion polymerization. II. Semicontinuous, delayed addition and seeded semicontinuous processes
Authors: Lee Ki‐Chang , Wi Han‐Ah 
Published: November 2009

AbstractA highly crosslinked, monodispersed polystyrene (PS) particle was prepared by the seeded semicontinuous dispersion polymerization using ready‐made monodispersed PS seed particles. The effects of Styrene (in 2nd stage)/Styrene (in PS seed) ratio, addition point and feeding time of divinylbenzene (DVB), concentration of DVB and polymerization temperature on the particle size, size distribution and morphology of the resulting particles were investigated. Monodispersed PS particles with 15 wt % of the DVB were prepared at 1/1 in St/St ratio, In comparison, highly crosslinked monodispersed and smooth‐surfaced PS particles containing up to 70 wt % of the DVB were effectively prepared at 0/1. 5% weight loss of the PS particles determined by TGA occurred from 353.3 to 389.6°C and the degree of swellability in toluene decreased from 113 to 101% as the DVB concentration increased from 10 to 70 wt %, implying increased thermal stability and solvent resistance due to the increase of the crosslink density. This study demonstrates that the seeded semicontinuous process, primarily with the starved condition at the second stage, is an efficient way to obtain highly crosslinked, monodispersed PS particles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of structural feature of aluminum coatings on mechanical and water barrier properties of metallized PET films
Authors: Garnier Géraldine , Yrieix Bernard , Brechet Yves , Flandin Lionel 
Published: November 2009

AbstractThis article focuses on description and evaluation of multilayer films, which are used for vacuum insulation panels (VIP). The materials investigated include a neat polyethylene terephthalate (PET) and PET films coated by chemical vapor deposition with different aluminum thicknesses. The aim of these investigations was to evaluate the influence of structural features on the physical properties of Al/PET systems. The morphological analyzes associated to water vapor permeability measurements showed that the metallized surface exhibited defects through which a small amount of water vapor can permeate. It is shown that the permeance varies linearly with the surface fraction occupied by pinholes which in turn changes linearly with the aluminum thickness. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Study of the biodegradable poly(ε‐caprolactone)/clay nanocomposite foams
Authors: Liu Hao , Han Changyu , Dong Lisong 
Published: November 2009

AbstractIn this article, biodegradable poly(ε‐caprolactone)/layered silicate nanocomposites were prepared and characterized. The dispersion state of modified clay in PCL matrix and its effect on thermal, rheological and mechanical properties of PCL were studied. The PCL/clay nanocomposites were then foamed using chemical foaming method. Cellular parameters such as mean cell size, cell wall thickness and cell densities of nanocomposite foams with different clay loading were collected. Effect of layered silicate on the structure and mechanical properties of PCL foams were evaluated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The influence of electrospinning parameters on the structural morphology and diameter of electrospun nanofibers
Authors: Jacobs Valencia , Anandjiwala Rajesh D. , Maaza Malik 
Published: November 2009

AbstractElectrospinning is a simple method of producing nanofibers by introducing electric field into the polymer solutions. We report an experimental investigation on the influence of processing parameters and solution properties on the structural morphology and average fiber diameter of electrospun poly ethylene oxide (PEO) polymer solution. Experimental trials have been conducted to investigate the effect of solution parameters, such as concentration, molecular weight, addition of polyelectrolyte in PEO solution, solvent effect, as well as governing parameter, such as applied voltage. The concentration of the aqueous PEO solution has shown noteworthy influence on the fiber diameter and structural morphology of electrospun nanofibers. At lower concentrations of PEO polymer solution, the fibers showed irregular morphology with large variations in fiber diameter, whereas at higher concentrations, the nanofibers with regular morphology and on average uniform fiber diameter were obtained. We find that the addition of polyelectrolytes, such as sodium salt of Poly acrylic acid (PAA) and Poly allylamine hydrochloride (PAH), increases the conductivity of PEO solutions and thereby decreases the bead formation in electrospun nanofibers. The increase in applied voltage has been found to affect the structural morphology of nanofiber while the addition of ethanol in PEO solution diminishes the bead defects. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
New sets of solubility parameters of linear and crosslinked aromatic polyamides
Authors: Fiori Stefano , Monticelli Orietta , Alzari Valeria , Mariani Alberto 
Published: November 2009

AbstractAs generally accepted, also in the case of polyamides linear and crosslinked polymeric materials are believed to be characterized by the same solution properties and, consequently, by the same solubility parameters. However, despite their great practical importance, a thorough study aimed to determine the best solvent media able to dissolve linear aromatic polyamides has not been performed yet or, at least, has not been published. In this study, we report on our study on the solubility parameters of linear and crosslinked aromatic polyamides. We demonstrate that the assumption of considering these two classes as having the same solubility properties can lead to dramatically erroneous results. Two new different sets for linear and crosslinked aromatic polyamides are proposed. Namely, linear poly(p‐phenylene terephthalamide) is characterized by δp, δd, and δH equal to 8.6, 18.4, and 11.3, respectively; by contrast, the corresponding values of the crosslinked aromatic polyamides taken into consideration are: 11.5, 16.8, and 10.2. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and characterization of copolymers based on poly(butylene terephthalate) and ethylene oxide‐poly(dimethylsiloxane)‐ethylene oxide
Authors: Vučković Marija V. , Antić Vesna V. , Govedarica Milutin N. , Djonlagić Jasna 
Published: November 2009

AbstractA series of thermoplastic elastomers based on ethylene oxide‐poly(dimethylsiloxane)‐ethylene oxide (EO‐PDMS‐EO), as the soft segment, and poly(butylene terephthalate) (PBT), as the hard segment, were synthesized by catalyzed two‐step, melt transesterification reaction of dimethyl terephthalate (DMT) with 1,4‐butanediol (BD) and α,ω‐dihydroxy‐(EO‐PDMS‐EO). Copolymers with a content of hard PBT segments between 40 and 90 mass % and a constant length of the soft EO‐PDMS‐EO segments were prepared. The siloxane prepolymer with hydrophilic terminal EO units was used to improve the miscibility between the polar comonomers, DMT and BD, and the nonpolar PDMS. The molecular structure and composition of the copolymers were determined by 1H‐NMR spectroscopy, whereas the effectiveness of the incorporation of α,ω‐dihydroxy‐(EO‐PDMS‐EO) into the copolymer chains was verified by chloroform extraction. The effects of the structure and composition of the copolymers on the melting temperatures and the degree of crystallinity, as well as on the thermal degradation stability and some rheological properties, were studied. It was demonstrated that the degree of crystallinity, the melting and crystallization temperatures of the copolymers increased with increasing mass fraction of the PBT segments. The thermal stability of the copolymers was lower than that of PBT homopolymer, because of the presence of thermoliable ether bonds in the soft segments. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Self synthesize of silver nanoparticles in/on polyurethane nanofibers: Nano‐biotechnological approach
Authors: Sheikh Faheem A. , Barakat Nasser A. M. , Kanjwal Muzafar A. , Jeon Seol‐Hee , Kang Hyung‐Sub , Kim Hak‐Yong 
Published: November 2009

AbstractIn this study, we are introducing a new class of Polyurethane (PU) nanofibers containing silver nanoparticles (NPs) by electrospinning. A simple method not depending on the addition of foreign chemicals has been used to self‐synthesize of silver NPs in/on PU nanofibers. Typically, a sol−gel consisting of AgNO3/PU/N,N‐dimethylformamide (DMF) has been electrospun and aged for a week, so silver NPs have been created in/on PU nanofibers. Syntheses of silver NPs were carried out by exploiting the reduction ability of the DMF solvent which is the main constituent to obtain PU electrospun nanofibers in decomposition of silver nitrate precursor into silver NPs. Physiochemical characterizations confirmed well oriented nanofibers and good dispersing of pure silver NPs. Various parameters affecting utilizing of the prepared nanofibers on various nano‐biotechnological fields have been studied. For instance, the obtained nanofiber mats were checked for mechanical properties which showed the improvement of the tensile strength upon increase in silver NPs content. Moreover, the nanofibers were subjected to 10 times successive washing experiments with using solid to liquid ratio of 3 : 5000 for 25 h, UV spectroscopy analysis reveals no losses of silver NPs from the PU nanofibers. 3T3‐L1 fibroblasts were cultured in presence of the designed nanofibers. The morphological features of the cells attached on nanofibers were examined by BIO‐SEM, which showed well attachment of cells to fibrous mats. The cytotoxicity results indicated absence of toxic effect on the 3T3‐L1 cells after cell culturing. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A comprehensive volumetric analysis of the cerebellum in children and adolescents with autism spectrum disorder
Authors: Scott Julia A. , Schumann Cynthia Mills , Goodlin‐Jones Beth L. , Amaral David G. 
Published: November 2009

AbstractMagnetic resonance imaging (MRI) and postmortem neuropathological studies have implicated the cerebellum in the pathophysiology of autism. Controversy remains, however, concerning the nature and the consistency of cerebellar alterations. MRI studies of the cross‐sectional area of the vermis have found both decreases and no difference in autism groups. Volumetric analysis of the vermis, which is less prone to “plane of section artifacts” may provide a more reliable assessment of size differences but few such studies exist in the literature. Here we present the results of a volumetric analysis of the structure of the whole cerebellum and its components in children and adolescents with autism spectrum disorders. Structural MRI's were acquired from 62 male participants (7.5 to 18.5 years‐old) who met criteria for the following age‐matched diagnostic groups: low functioning autism, high functioning autism (HFA), Asperger syndrome, and typically developing children. When compared to controls, the midsagittal area of the vermis, or of subgroups of lobules, was not reduced in any of the autism groups. However, we did find that total vermis volume was decreased in the combined autism group. When examined separately, the vermis of only the HFA group was significantly reduced compared to typically developing controls. Neither IQ nor age predicted the size of the vermis within the autism groups. There were no differences in the volume of individual vermal lobules or cerebellar hemispheres. These findings are discussed in relation to the pathology of autism and to the fairly common alterations of vermal morphology in various neurodevelopmental disorders.
Does EMDR reduce post‐traumatic stress disorder symptomatology in combat veterans?
Authors: Albright David L. , Thyer Bruce 
Published: November 2009

AbstractPrior meta‐analyses have suggested that eye‐movement desensitization and reprocessing (EMDR) may be effective in alleviating the symptoms of post‐traumatic stress disorder (PTSD). EMDR is now being recommended as a treatment for military combat veterans who suffer from PTSD. We provide a review of published outcome studies that appeared in print from 1987 – April, 2008 which examined the specific effects of EMDR on PTSD among military combat veterans. Studies were identified through electronic bibliographic databases, web sites, and manual searches of article reference lists. A total of six randomized controlled trials (RCTs) and three quasi‐experimental studies met our inclusionary criteria and are reviewed. The evidence supporting the use of EMDR to treat combat veterans suffering from PTSD is sparse and equivocal, and does not rise to the threshold of labeling the therapy as an empirically supported treatment. It is premature to incorporate EMDR into routine care for veterans to alleviate combat‐related PTSD. EMDR needs a considerably stronger evidentiary foundation which includes large‐scale RCTs involving credible placebo controlled treatment conditions. Copyright © 2009 John Wiley & Sons, Ltd.
Importance of the spatial display of charged residues in heparin–peptide interactions
Authors: Rullo Anthony , Nitz Mark 
Published: November 2009

AbstractMany studies have examined consensus sequences required for protein‐glycosaminoglycan interactions. Through the synthesis of helical heparin binding peptides, this study probes the relationship between spatial arrangement of positive charge and heparin binding affinity. Peptides with a linear distribution of positive charge along one face of the α‐helix had the highest affinity for heparin. Moving the basic residues away from a single face resulted in drastic changes in heparin binding affinity of up to three orders of magnitude. These findings demonstrate that amino acid sequences, different from the known heparin binding consensus sequences, will form high affinity protein‐heparin binding interactions when the charged residues are aligned linearly. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 290–298, 2010.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Development of a liquid chromatography–isotope dilution mass spectrometry method for quantification of fentanyl in human plasma
Authors: Lu Chuan , Jia Jing‐ying , Gui Yu‐zhou , Liu Gang‐yi , Shi Xiao‐jin , Li Shui‐jun , Yu Chen 
Published: November 2009

AbstractFentanyl is a potent analgesic drug in relieving chronic pain in patients. In this report, we present a simple, reliable and sensitive LC–ID/MS method for the quantification of fentanyl in human plasma. LC‐ID/MS analysis was carried out on a triple quadrupole mass spectrometer operated in positive electrospray ionization multiple‐reaction‐monitoring using the transitions m/z 337.6 → 187.9 for fentanyl and m/z 342.6 → 187.9 for the internal standard (D5‐fentanyl). The calibration curve covered the range 0.02–10 ng/mL. The intra‐ and inter‐batch precision were less than 6.739 and 3.126% for fentanyl and IS, with accuracy from 94.16 to 102.0%. The lower limit of quantification was identifiable and reproducible at 0.02 ng/mL. The validated method offered increased sensitivity and wide linear concentration range. This method was successfully adopted for the evaluation of bioequivalence of two fentanyl transdermal preparations after single dose administration to 20 Chinese pain‐patients. Copyright © 2009 John Wiley & Sons, Ltd.
Isothiocyanates as derivatization reagents for amines in liquid chromatography/electrospray ionization–tandem mass spectrometry
Authors: Santa Tomofumi 
Published: November 2009

AbstractThe applicability of 3‐pyridyl isothiocyanate, p‐(dimethylamino)phenyl isothiocyanate and m‐nitrophenyl isothiocyanate as the derivatization reagents for amines in high‐performance liquid chromatography/electrospray ionization–tandem mass spectrometry (LC/ESI‐MS/MS) was examined. The generated derivatives of amines with these reagents were favorably separated on the reversed‐phase column and detected by ESI‐MS/MS. The C–N bond of the generated thiourea structure was efficiently cleaved by collision‐induced dissociation and gave the single and intense product ion. Among the three reagents, 3‐pyridyl isothiocyanate was the most suitable as the derivatization reagent with regard to the reactivity to amines and the detection sensitivity. Copyright © 2009 John Wiley & Sons, Ltd.
A sensitive and specific liquid chromatography/tandem mass spectrometry method for quantification of nevirapine and its five metabolites and their pharmacokinetics in baboons
Authors: Ren Chen , Fan‐Havard Patty , Schlabritz‐Loutsevitch Natalia , Ling Yonghua , Chan Kenneth K. , Liu Zhongfa 
Published: November 2009

AbstractA highly sensitive and specific LC‐MS/MS assay was developed and validated to quantify nevirapine (NVP) and its five metabolites [2‐, 3‐, 8‐, 12‐hydroxyl NVP (OHNVP) and 4‐carboxyl NVP (CANVP)] simultaneously in baboon serum and the assay was used to characterize their pharmacokinetic studies of an oral‐dose escalation study in baboon. The lower limit of quantification (LLOQ) for NVP and its four hydroxyl nevirapine metabolites was 1.0 ng/mL and for 4‐CANVP was 5.0 ng/mL. The between‐run and within‐run precisions and accuracies at four quality control concentrations (1, 5, 50 and 500 ng/mL) were evaluated in baboon serum with less than 14% variation and 93–114% accuracies (n= 6), except for the LLOQ for 2‐OHNVP, which had an accuracy of 115.8% for between‐run validation. The pharmacokinetics of NVP and its five metabolites in non‐pregnant baboons by a single‐dose escalation study were also profiled. The major metabolites detected were 4‐CANVP and 12‐OHNVP. 3‐OHNVP and 2‐OHNVP were the minor metabolites with only a trace amount of 2‐OHNVP detected in some pharmacokinetic samples. No 8‐OHNVP was observed in all of the pharmacokinetic samples. In addition, the fragmentation for the four hydroxyl metabolite isomers is also discussed. Copyright © 2009 John Wiley & Sons, Ltd.