bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accelerating the degradation of polyolefins through additives and blending
Authors: Liu Xingxun , Gao Chengcheng , Sangwan Parveen , Yu Long , Tong Zhen 
Published: April 2014

ABSTRACTPolyolefins are popular because of their low price, useful properties, broad supply chains, and mature processing facilities, but they do not easily degrade in the natural environment, and hence, the development of degradable polyolefins has attracted increasing interest. Oxidative degradation and blending with natural polymers can accelerate the degradation of polyolefins in natural environments. In this article, we review the research and developments in the acceleration of the degradation of polyolefin blends and composites, including both the fundamental science, such as the degradation mechanisms and characterizations, and application techniques, such as the processing conditions and formulations. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40750.
Synthesis and aqueous solution properties of hydrophobically modified polyacrylamide
Authors: Lu Cuige , Li Wenbo , Tan Ying , Liu Chang , Li Pengchong , Xu Kun , Wang Pixin 
Published: April 2014

ABSTRACTHydrophobically modified polyacrylamide (HMPAM) is synthesized by a free radical micellar polymerization method with low amounts of anionic long‐chain alkyl, sodium 9‐(and 10)‐acrylamidostearate (NaAAS), which is derived from a renewable resource material, oleic acid. In this progress, the molar ratio of Sodium dodecyl sulfate (SDS) to NaAAS is adjusted, so polymers with different lengths of the hydrophobic blocks (NH = 3 and NH = 6) are obtained. The copolymers are characterized by 1H NMR, and the polymer weight and polydispersity are determined by gel permeation chromatography. The solution behaviors of the copolymers are studied as functions of concentrations, pH, and added electrolytes by steady‐flow and oscillatory experiments. The viscosities of these HMPAMs increase enormously above the critical concentration (c*). The sample with longer hydrophobic blocks exhibits better thickening effect. The rheological behaviors of aqueous solutions of HMPAMs are also investigated at different pH and brine environments. Low pH or the presence of brine promotes the intramolecular associating of hydrophobes for the both copolymers in semidilute solutions. The introduction of ionizable carboxylic group on the long hydrophobic side chain significantly influences the aggregation behaviors of the copolymers, leading to unique solution behaviors of the poly(AAm/NaAAS) copolymers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40754.
Mechanical properties of PLA/PBS foamed composites reinforced by organophilic montmorillonite
Authors: Zhou Jintang , Yao Zhengjun , Zhou Chang , Wei Dongbo , Li Shuqin 
Published: April 2014

ABSTRACTPorous materials have specific properties, such as high surface area, high permeability, lightweight, and low thermal conductivity. In foaming process of thermoplastics, high melt viscosity is indispensable. Neither poly(lactic acid) (PLA) nor poly(butylene succinate) (PBS) has sufficient melt viscosity. In this manuscript, Organophilic montmorillonite (OMMT) was employed to improve the foaming performance PLA/PBS blends. Mechanical tests were undertaken to compare the performance change of PLA/PBS foams before and after reinforcement of OMMT. The compression feature of PLA/PBS foams was discussed. X‐ray diffraction (XRD) and scanning electron microscopes were performed to investigate the interaction between OMMT and PLA/PBS foams and the influence of OMMT on cell structure. The results indicated that OMMT can improve the effect of foaming markedly. With 3 wt % OMMT, The compressive strength, flexural strength, and impact strength raised up to 9.2 MPa, 14.0 MPa, and 31.2 kJ/m2, respectively, and the average size of cells changed from 475.6 to 261.4 µm. FT‐IR, TGA, and XRD analysis suggested that CTAC has inserted into the Na‐MMT platelets and OMMT platelets are more likely to be intercalated or completely separated in PLA/PBS matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40773.
Preparation of thiourea functionalized polyvinyl alcohol‐coated magnetic nanoparticles and their application in Pb2+ ions adsorption
Authors: Xiong Wubin , Guan Yueping , Guo Chen , Yang Mingzhu , Xia Tingting , Zhao Shen 
Published: April 2014

ABSTRACTWe have prepared a novel kind of magnetic nanoparticle with high adsorption capacity and good selectivity for Pb2+ ions by modifying the magnetic nanoparticles with polyvinyl alcohol (PVA) and thiourea. The resultant magnetic nanoparticles were used to adsorb Pb2+ ions from aqueous solution. The influence of the solution pH, the adsorption time, the adsorption temperature, coexisting ions, and the initial concentration of Pb2+ ions on the adsorption of Pb2+ ions were investigated. The results indicated that Pb2+ ions adsorption was an endothermic reaction, and adsorption equilibrium was achieved within 30 min. The optimal pH for the adsorption of Pb2+ ions was pH 5.5, and the maximum adsorption capacity of Pb2+ ions was found to be 220 mg/g. Moreover, the coexisting cations such as Ca2+, Co2+, and Ni2+ had little effect on adsorption of Pb2+ ions. The regeneration studies showed that thiourea functionalized PVA‐coated magnetic nanoparticles could be reused for the adsorption of Pb2+ ions from aqueous solutions over five cycles without remarkable change in the adsorption capacity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40777.
On allocating redundancies to k‐out‐of‐ n reliability systems
Authors: You Yinping , Li Xiaohu 
Published: April 2014

AbstractFor two components in series and one redundancy with their lifetimes following the proportional hazard models, we build the likelihood ratio order and the hazard rate order for lifetimes of the redundant systems. Also, for k‐out‐of‐ n system with components’ lifetimes having the arrangement increasing joint density and the redundancies having identically distributed lifetimes, allocating more redundancies to weaker components is shown to help improve the system's reliability. Copyright © 2014 John Wiley & Sons, Ltd.
A new and highly sensitive resonance Rayleigh scattering assay for lysozyme using aptamer–nanogold as a probe
Authors: Ma Lu , Zhang Xinghui , Liang Aihui , Liu Qingye , Jiang Zhiliang 
Published: April 2014

ABSTRACTGold nanoparticles (GN), 10 nm in size, were modified by using lysozyme aptamer (Apt) to obtain a stable Apt–GN probe in pH 8.05 Tris/HCl buffer solutions containing 0.04 mol/L NaCl. Upon addition of lysozyme (LYS), it reacted with the Apt of the probe to form a very stable Apt–LYS complex and to release GNs, which aggregated to form large clusters with a resonance Rayleigh scattering (RRS) peak at 368 nm. The enhanced peak intensity, ΔI, was linear to the LYS concentration in the range 0.2–5.2 nmol/L, with a detection limit of 0.05 nmol/L. The influence of foreign substance was tested, and the results showed that this RRS method has high selectivity. This Apt–GN RRS method was applied to the analysis of LYS in a real sample, with satisfactory results. Copyright © 2014 John Wiley & Sons, Ltd.
Evaluation of trapping parameters of γ‐rays irradiated Dy3+‐doped LaPO4 phosphors
Authors: Pimpalshende D. M. , Dhoble S. J. 
Published: April 2014

ABSTRACTThermoluminescence (TL) materials are widely used in radiation measurements. The best‐known applications of TL materials are in the dosimetry of ionizing radiation, and in CTV screen phosphors, scintillators, X‐ray laser materials, etc. The TL glow curve and its kinetic parameters for annealed LaPO4 at different constant temperatures and for Dy3+‐doped LaPO4 phosphors irradiated by gamma‐rays are reported here. The samples were irradiated using a 60Co gamma‐ray source at a dose of 10 Gy and the heating rate used for TL measurements was 5ºC/s. The samples were characterized using X‐ray diffraction (XRD), Fourier transform infrared, transmission electron microscopy and TL techniques. The XRD pattern shows that the prepared phosphor has a good crystalline structure with an average crystallite size of ~ 18 nm. The samples show good TL peaks for 0.05, 0.1 and 0.2 mole % doping concentrations of Dy3+ ions and anneal above 400ºC. The TL glow curve characteristics of annealed LaPO4 and Dy3+‐doped LaPO4 were analyzed and trapping parameters calculated using various methods. All TL glow curves obey the second‐order kinetics with a single glow peak, which reveals that only one set of trapping parameter is set for a particular temperature. The TL sensitivity was found to depend upon the annealing temperature and Dy3+ doping concentration. The prepared sample may be a new nano phosphor and be useful in TL dosimetry. Copyright © 2014 John Wiley & Sons, Ltd.
Spectrofluorimetric determination of amisulpride and bumidazone in raw materials and tablets
Authors: Walash M. I. , Belal F. , Tolba M. M. , Halawa M. I. 
Published: April 2014

ABSTRACTA highly sensitive, simple and rapid spectrofluorimetric method was developed for the determination of amisulpride (AMS) and bumidazone (BUM) in tablet form. The proposed method is based on measuring the native fluorescence of the studied drugs in methanol at 360 and 344 nm after excitation at 276 and 232 nm for AMS and BUM, respectively. The fluorescence–concentration plots were rectilinear over the ranges of 5.0–60.0 ng/mL for AMS and 0.5–5.0 µg/mL for BUM. The lower detection limits were 0.70 ng/mL and 0.06 µg/mL, and the lower quantification limits were 2.0 ng/mL and 0.18 µg/mL for AMS and BUM, respectively. The method was successfully applied for the analysis of AMS and BUM in commercial tablets. Statistical evaluation and comparison of the data obtained using the proposed and comparison methods revealed good accuracy and precision for the proposed method. Copyright © 2014 John Wiley & Sons, Ltd.
A New Bifunctional Chelator Enables Facile Biocoupling and Radiolabeling as the Basis for a Bioconjugation Kit
Authors: Barandov Ali , Grünstein Dan , Apostolova Ivalaya , Buchert Ralph , Roger Michel , Brenner Winfried , Abram Ulrich , Seeberger Peter H. 
Published: April 2014

AbstractA new tridentate bifunctional chelator, N‐(‐2‐picolyl)(‐4‐hydroxy)(‐3‐amino)benzoic acid (PHAB), was designed to efficiently coordinate the [99mTc(CO)3]+ core and facilitate coupling reactions to biomolecules. The chelator can be procured in the form of the corresponding benzotriazole ester (PHAB‐OBT), which can be stored and used as a bioconjugation kit. PHAB‐OBT reacts with modified carbohydrates with high selectivity and efficiency in a single step in both aqueous and organic media. As is desirable for a kit, no complicated chemical bench work is required. Glycoconjugate postlabeling resulted in neutral radiolabeled glycans with high radiochemical yields. Prelabeling approaches were assessed by successive reaction of PHAB‐OBT with the [99mTc(CO)3]+ core and a modified galactose model. The radiolabeled galactose was obtained in 84 % yield as defined by HPLC analysis. Biodistribution of the radioactive 99mTc‐labeled chelator, as well as the glycoconjugates, were examined in mice. Noticeably different biodistribution patterns were observed that reflect trends in the uptake of carbohydrate analogues by various organs.
How to Modulate Catalytic Properties in Nanosystems: The Case of Iron–Ruthenium Nanoparticles
Authors: Kelsen Vinciane , Meffre Anca , Fazzini Pier‐Francesco , Lecante Pierre , Chaudret Bruno 
Published: April 2014

AbstractUltrasmall FeRu bimetallic nanoparticles were prepared by co‐decomposition of two organometallic precursors, {Fe[N(Si(CH3)3)2]2}2 and (η4‐1,5‐cyclooctadiene)(η6‐1,3,5‐cyclooctatriene)ruthenium(0) (Ru(COD)(COT)), under dihydrogen at 150 °C in mesitylene. A series of FeRu nanoparticles of sizes of approximately 1.8 nm and incorporating different ratios of iron to ruthenium were synthesized by varying the quantity of the ruthenium complex introduced (Fe/Ru=1:1, 1:0.5, 1:0.2, and 1:0.1). FeRu nanoparticles were characterized by TEM, high‐resolution TEM, and wide‐angle X‐ray scattering analyses. Their surface was studied by hydride titration and IR spectroscopy after CO adsorption and their magnetic properties were analyzed by using a superconducting quantum interference device (SQUID). The FeRu nanoparticles were used as catalysts in the hydrogenation of styrene and 2‐butanone. The results indicate that the selectivity of the nanoparticle catalysts can be modulated according to their composition and therefore represent a case study on fine‐tuning the reactivity of nanocatalysts and adjusting their selectivity in a given reaction.
A Copper‐Catalyzed Variant of the Michaelis–Arbuzov Reaction
Authors: Ballester Jorge , Gatignol Jérémie , Schmidt Guntram , Alayrac Carole , Gaumont Annie‐Claude , Taillefer Marc 
Published: April 2014

AbstractAs part of our studies on copper‐catalyzed arylation of nucleophiles, we report on Michaelis–Arbuzov reactions with a novel catalytic system, featuring a copper(I) salt as precatalyst without any additional ligand. This procedure is an interesting alternative to the use of expensive and toxic transition metals (nickel, palladium) traditionally used as catalysts in Michaelis–Arbuzov reactions. Our approach allows the synthesis from triethylphosphite, diethyl aryl phosphonite, and diaryl ethylphosphinite of various aryl phosphonates, aryl phosphinates, and aryl phosphine oxides, respectively. These families of compounds are essential owing to their respective importance in bioorganic and medical chemistry, their applicability as flame retardants, and their usability in coordination chemistry and catalysis.
Design of Maleimide‐Functionalised Electrodes for Covalent Attachment of Proteins through Free Surface Cysteine Groups
Authors: Wright Emma J. , Sosna Maciej , Bloodworth Sally , Kilburn Jeremy D. , Bartlett Philip N. 
Published: April 2014

AbstractMixed two‐component monolayers on glassy carbon are prepared by electrochemical oxidation of N‐(2‐aminoethyl)acetamide and mono‐N‐Boc‐hexamethylenediamine in mixed solution. Subsequent N‐deprotection, amide coupling and solid‐phase synthetic steps lead to electrode‐surface functionalisation with maleimide, with controlled partial coverage of this cysteine‐binding group at appropriate dilution for covalent immobilisation of a model redox‐active protein, cytochrome c, with high coverage (≈7.5 pmol cm−2).
Harnessing neurogenesis for the possible treatment of Parkinson's disease
Authors: Lamm Omri , Ganz Javier , Melamed Eldad , Offen Daniel 
Published: April 2014

ABSTRACTThe discovery of neurogenesis in the adult brain has created new possibilities for therapeutics in neurodegenerative diseases. Neural precursor cells, which have been found in various parts of the brain, e.g., the subventricular zone (SVZ) and substantia nigra (SN), have promising potential to replace the extensive loss of neurons occurring in neurodegenerative disorders. In Parkinson's disease (PD) the degeneration of nigral dopaminergic neurons and consequently the nigrostriatal pathway, which has been found to innervate proximally to the SVZ, causes motor and cognitive impairments. There is strong evidence that neurogenesis is impaired in PD, which has been related to the nonmotor symptoms of the disease. Recent evidence supports that this impairment in neurogenesis is partially caused by the lack of dopamine in one of the adult neurogenic niches, the SVZ. Thus, restoring the dopaminergic pathway in PD patients may have implications not only for motor function improvement, but for other cognitive and autonomic symptoms. Currently, there are no effective treatments that can stop or reverse the neurodegeneration process in the brain. Here we review the neurogenic process and observed alterations found in PD animal models and postmortem brains of PD patients. Finally, we review several attempts to stimulate the neurogenic process for nigral and/or striatal dopaminergic restoration by transgenic expression, exercise, or cell therapy. J. Comp. Neurol. 522:2817–2830, 2014. © 2014 Wiley Periodicals, Inc.
Creating a gateway that enables large‐scale science coopetition
Authors: Crivelli Silvia , Dooley Rion , Holmes Raquell , Mock Stephen ,   The WeFold Community
Published: April 2014

SummaryThis paper describes the WeFold gateway that provides a social and technical environment for the first large‐scale attempt at collaboration within the context of the Critical Assessment of techniques for protein Structure Prediction (CASP) competition. CASP is a biennial worldwide experiment created 20 years ago to advance the field of protein folding, one of the grand challenges in modern science. The WeFold experiment was started in CASP10 (the 10th CASP) to bring together scientists from different disciplines to brainstorm online, share ideas and codes, and synergistically develop new methodologies. The goal is to positively shake up the field to stimulate breakthrough advances. Copyright © 2014 John Wiley & Sons, Ltd.
Spatial genetic features of eastern oysters (Crassostrea virginica Gmelin) in the Gulf of Mexico: northward movement of a secondary contact zone
Authors: Anderson Joel D. , Karel William J. , Mace Christopher E. , Bartram Brian L. , Hare Matthew P. 
Published: April 2014

AbstractThe eastern oyster (Crassostrea virginica Gmelin) is an economically and ecologically valuable marine bivalve occurring in the Gulf of Mexico. This study builds upon previous research that identified two divergent populations of eastern oysters in the western Gulf of Mexico. Allelic and genotypic patterns from 11 microsatellite markers were used to assess genetic structure and migration between the previously described oyster populations in Texas. The main findings are as follows: (1) there are two distinct populations (FST = 0.392, P < 0.001) of oysters that overlap in the Corpus Christi/Aransas Bay estuarine complex in Texas, (2) the distribution of genotypes among individuals in the contact zone suggests limited hybridization between populations, (3) the variables of salinity, temperature, dissolved oxygen, turbidity and depth are not correlated with allele frequencies on reefs in the contact zone or when analyzed across Texas, and (4) there is little evidence of directional selection acting on the loci assayed here, although patterns at four markers suggested the influence of balancing selection based on outlier analyses. These results are consistent with long‐term historical isolation between populations, followed by secondary contact. Recent hydrological changes in the area of secondary contact may be promoting migration in areas that were previously inhospitable to eastern oysters, and observed differences in the timing of spawning may limit hybridization between populations. Comparison of these findings with the results of an earlier study of oysters in Texas suggests that the secondary contact zone has shifted approximately 27 km north, in as little as a 23‐year span.
One‐Pot Transformation of Methylarenes into Aromatic Aldehydes under Metal‐Free Conditions
Authors: Tabata Masayuki , Moriyama Katsuhiko , Togo Hideo 
Published: April 2014

AbstractOn the basis of studies of the transformation of benzylic bromides into the corresponding aromatic aldehydes by treatment with N‐methylmorpholine N‐oxide, various methylarenes were treated either with DBDMH in the presence of AIBN in acetonitrile at reflux (Method A) or with NBS in CCl4 under irradiation with a tungsten lamp at 30 °C (Method B), followed by treatment with N‐methylmorpholine N‐oxide to provide aromatic aldehydes in good yields. These methods could be adopted in one‐pot transformations of methylarenes into aromatic aldehydes under conditions free of less toxic reagents and transition metals.
Neighboring ortho‐Hydroxy Group Directed Catalytic Asymmetric Triple Domino Reactions of Acetaldehyde with (E)‐2‐(2‐Nitrovinyl)phenols
Authors: Ramachary Dhevalapally B. , Reddy P. Srinivasa , Prasad M. Shiva 
Published: April 2014

AbstractHerein we demonstrate the utilization of neighboring ortho‐hydroxy group participation in the pretransition state of enamine‐ and iminium‐based triple domino reactions for high reactions rates and asymmetric induction. Enantiomerically pure, drug‐like chromanes and tetrahydro‐6H‐benzo[c]chromenes having three to four contiguous stereocenters are synthesized through triple domino Michael/aldol/oxa‐Michael reactions catalyzed by (R)‐2‐{diphenyl[(trimethylsilyl)oxy]methyl}pyrrolidine followed by Wittig and Michael/Wittig–Horner reactions from simple precursors under mild conditions.
Mortality salience and evaluations of in‐group versus out‐group critics: The role of criticism legitimacy and perceived threat
Authors: Khoo Bernice L. Z. , See Ya Hui Michelle 
Published: April 2014

AbstractSignificant terror management research has examined the impact of mortality salience on evaluations toward in‐group versus out‐group and attitudinally similar versus dissimilar others. However, relatively little research has examined evaluations when group membership is disentangled from attitude similarity. The current research examined the impact of mortality salience on evaluations toward in‐group and out‐group critics when people are less likely to rely on group membership as a heuristic. In Experiment 1, the results showed that in the control condition, participants rated an in‐group member who provided unjustified criticism more positively than an out‐group member who provided the same criticism. Under mortality salience, the reverse occurred: An in‐group member who provided unjustified criticism was rated more negatively than an out‐group member. Experiment 2 showed that under mortality salience, the derogation of an in‐group critic who provided unjustified criticism was mediated by perceptions of threat. Implications for reactions to group‐directed criticism as well as mortality salience effects are discussed. Copyright © 2014 John Wiley & Sons, Ltd.
The ultra‐social animal
Authors: Tomasello Michael 
Published: April 2014

AbstractIn evolutionary perspective, what is most remarkable about human sociality is its many and diverse forms of cooperation. Here, I provide an overview of some recent research, mostly from our laboratory, comparing human children with their nearest living relatives, the great apes, in various tests of collaboration, prosocial behavior, conformity, and group‐mindedness (e.g., following and enforcing social norms). This is done in the context of a hypothetical evolutionary scenario comprising two ordered steps: a first step in which early humans began collaborating with others in unique ways in their everyday foraging and a second step in which modern humans began forming cultural groups. Humans' unique forms of sociality help to explain their unique forms of cognition and morality. © 2014. The Authors. European Journal of Social Psychology published by John Wiley & Sons, Ltd.