bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a General and Practical Iron Nitrate/TEMPO‐Catalyzed Aerobic Oxidation of Alcohols to Aldehydes/Ketones: Catalysis with Table Salt
Authors: Ma Shengming , Liu Jinxian , Li Suhua , Chen Bo , Cheng Jiajia , Kuang Jinqiang , Liu Yu , Wan Baoqiang , Wang Yuli , Ye Juntao , Yu Qiong , Yuan Weiming , Yu Shichao 
Published: April 2011

AbstractOxidation of alcohols is a fundamental transformation related to our daily life. Traditional approaches with at least one stoichiometric amount of oxidants are expensive and cause serious environmental burdens. There are many reports on the aerobic oxidation of simple alcohols such as alkyl or phenyl carbinols and allylic alcohols, which used oxygen or air as the environmentally benign oxidant forming water as the only by‐product. However, no such protocol has been reported for allenols and propargylic alcohols. Thus, it still highly desirable to develop efficient room temperature oxidations of alcohols with a wide scope including allenols and propargylic alcohols. In this paper, an efficient and clean aerobic oxidation of so far the widest spectrum of alcohols using 1 atm of oxygen or air, producing aldehydes/ketones at room temperature in fairly high isolated yields mostly within a couple of hours is described. It is interesting to observe that the reaction has been efficiently expedited by a catalytic amount of sodium chloride in easily recoverable 1,2‐dichloroethane. A mechanism involving NO and NO2 has been proposed based on the results of the control experiments and GC‐MS studies of the in‐situ formed gas phase of the reaction mixture.
An Easy Entry to Optically Active Spiroindolinones: Chiral Brønsted Acid‐Catalysed Pictet–Spengler Reactions of Isatins
Authors: Duce Sara , Pesciaioli Fabio , Gramigna Lucia , Bernardi Luca , Mazzanti Andrea , Ricci Alfredo , Bartoli Giuseppe , Bencivenni Giorgio 
Published: April 2011

AbstractThe first catalytic asymmetric Pictet–Spengler reaction of isatins is presented. BINOL‐derived phosphoric acids were found to be competent catalysts for this transformation, giving challenging spirooxindole structures bearing a quaternary stereocentre with generally good results. The 1,2,3,4‐tetrahydro‐β‐carboline products (spiroindolinones) are the core of some newly discovered anti‐malarial agents.
Improved nonlinear process monitoring using KPCA with sample vector selection and combined index
Authors: Sumana C. , Bhushan Mani , Venkateswarlu Ch. , Gudi Ravindra D. 
Published: April 2011

AbstractKernel principal component analysis (KPCA) has been found to be one of the promising methods for nonlinear process monitoring in recent years. It effectively captures the data nonlinearities by transforming the original data using nonlinear kernel functions and then performs linear PCA in high‐dimensional feature space F. However, KPCA is computationally intense, as it needs the solution of the eigenvalue decomposition problem involving a high‐dimensional kernel matrix. The present work addresses this issue by adopting a sample vector selection (SVS) scheme that facilitates the analysis in a lower dimensional kernel space formed by a set of optimally selected transformed samples in F. These sample vectors are selected through an iterative sequential forward selection procedure based on a geometric consideration. Furthermore, the efficiency of the KPCA methodology is improved by proposing a combined index‐based process monitoring in the reduced kernel space. The performance of the proposed methodology is evaluated by applying it to a complex nonlinear Tennessee Eastman process. The results demonstrate the better fault detection ability of the proposed methodology in terms of lower computational effort and reduced false alarm and missed detection rates. Copyright © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.
Preparation of core–shell microcapsules using nanodispersed fibroin
Authors: Kim Eun Jong , Lee Shin Young , Hur Won 
Published: April 2011

AbstractAn elaborate control of fibroin self‐assembly is critical in determining the size, structure, and release properties of a microcapsule. This report describes the preparation of microspheres in the submicron range using an aqueous fibroin solution nanoemulsified in decane with a mixed detergent solution of Tween 80 and Span 80. Nanodispersed water droplets containing fibroin molecules were dried under vacuum to facilitate the coalescence of fibroin and then transformed to suspended particles in the range of 200–1200 nm in diameter. The method was also applied to encapsulate dextran and fluorescein isothiocyanate‐dextran (FITC‐dextran), producing core–shell structured microcapsules as identified by scanning electron microscopy and confocal scanning laser microscopy. The microcapsule yield was in the range of 82–85% per fibroin consumed. The encapsulation efficiency was 64% for the microcapsules fabricated from a nanoemulsion containing 0.1 mg of FITC‐dextran per mg fibroin. Approximately 70.5% of the core material was released within 2 weeks. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Influence of morphology effects on electrical properties in XLPE
Authors: Nilsson S. , Hjertberg T. , Smedberg A. , Sonerud B. 
Published: April 2011

AbstractThis study elucidates the influence of differences in crosslink structure and crosslink density on water tree growth, electrical tree growth, and electrical breakdown strength. One reference LDPE was compared with a LDPE containing a higher number of vinyl groups, introduced via the copolymerisation with a diene. Because of the chemical difference, the initially formed crosslink structure will be different for the materials. A range of various crosslink densities was considered for the two materials. It was found that along with a noticeable change in morphology after crosslinking, significant changes in particularly water tree growth, electrical tree growth, and electrical breakdown strength could be observed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Improvement of impact properties of polypropylene by modification with very low‐density polyethylene
Authors: Kim Eung Soo , Shim Jae Hun , Woo Ji Yoon , Lee Keun Young , Yoon Jin‐San 
Published: April 2011

AbstractVery low‐density polyethylene (VLDPE) was compounded with polypropylene (PP) to improve its impact strength. VLDPE was modified by grafting 3‐(trimethoxysilyl) propyl methacrylate silane (MS) to VLDPE to prepare mVLDPE. PP was melt‐mixed either with VLDPE or mVLDPE together with Cloisite®20A (C20A). The composites exhibited a phase‐separated morphology, irrespective of whether the VLDPE had been modified with the silane compounds or not. Incorporation of C20A decreased the domain size of the dispersed phases of both PP/VLDPE and PP/mVLDPE blends. The tensile strength and elongation at break of PP/VLDPE and PP/mVLDPE were improved by the addition of C20A. In contrast, their impact strengths were reduced by the clay. However, the decrease in impact strength was less significant in PP/mVLDPE/C20A than in PP/VLDPE/C20A. The superior mechanical properties of PP/mVLDPE/C20A over PP/VLDPE/C20A were attributed to enhanced interfacial interactions originating from chemical reactions between silane residues on mVLDPE and the silanol groups of C20A. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Thermal properties of polyurethane binder with 2‐(ferrocenylpropyl)dimethylsilane‐grafted hydroxyl‐terminated polybutadiene
Authors: Cho Bong‐Sang , Noh Si‐Tae 
Published: April 2011

AbstractWe synthesized a ferrocene‐based burning rate catalyst, 2‐(ferrocenylpropyl) dimethylsilane (FPDS). FPDS‐grafted hydroxyl‐terminated polybutadiene (FPDS‐g‐HTPB) was synthesized using hydrosilylation with a Pt catalyst. The structures of FPDS and FPDS‐g‐HTPB were investigated by Fourier transform infrared spectroscopy and nuclear magnetic resonance. HTPB‐based polyurethanes were prepared from HTPB, 6‐hexamethylenediisocyanate (HDI), and HDI‐trimer. Polyurethane network was prepared with an (NCO)/(OH) ratio of 1.05 and an [isocyanate trimer]/[total NCO] ratio of 0.3 then subjected to accelerated aging at 80°C. The thermal behaviors of the polyurethane network were compared using differential scanning calorimetry and thermal gravity analysis. The glass transition temperatures (Tg) of HTPB and FPDS‐g‐HTPB were −76°C and −47°C, respectively. The value of Tg for the networked polyurethane was not influenced by HDI‐trimer content but by FPDS content. The decomposition temperature of the neat HTPB‐based polyurethane network was lower than that of the FPDS‐g‐HTPB‐based polyurethane networks. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Chemorheology and thermomechanical characteristics of benzoxazine‐urethane copolymers
Authors: Rimdusit Sarawut , Bangsen Wanchat , Kasemsiri Pornnapa 
Published: April 2011

AbstractIn this research, processability and some important thermomechanical properties of polybenzoxazine (BA‐a) modified with a highly flexible urethane elastomer (PU) are discussed. This copolymer has been reported to show synergy in its glass transition temperature and some mechanical properties thus provides a fascinating group of high temperature polymers with enhanced flexibility. The results reveal that a processing window of the BA‐a/PU mixtures is widened with the increasing urethane prepolymer fraction, that is, the liquefying temperature is lowered and the gel point shifted to higher temperature with the amount of the PU. Synergism in glass transition temperature (Tg) of this copolymer was clearly confirmed, i.e., Tg's of the BA‐a/PU alloys were significantly greater than those of the parent resins, i.e., BA‐a (Tg = 166°C) and PU (Tg = − 70°C). In addition, flexural modulus was found to systemically decrease from 5.4 GPa of the neat polybenzoxazine to 2.1 GPa at 40% by weight of the PU. Flexural strength of the alloys also shows a synergistic behavior at the BA‐a/PU ratio of 90/10. Coefficient of thermal expansion of the polymer alloys were also found to show a minimum value at BA‐a/PU = 90/10. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Design of an ammonium dinitramide compatible polymer matrix
Authors: Rahm Martin , Malmström Eva , Eldsäter Carina 
Published: April 2011

AbstractTo enable future environmentally friendly access to space by means of solid rocket propulsion a viable replacement to the toxic ammonium perchlorate (AP) oxidizer is needed. Ammonium dinitramide (ADN) holds great promise as a green replacement. Unfortunately compatibility issues with many polymer binder systems have hampered the development of ADN‐based formulations. Herein we present proof‐of‐concept of a polymer cure system based on hyperbranched copolymers of 3‐ethyl‐3‐(hydroxymethyl)oxetane (TMPO) and tetrahydrofuran (THF). The partly alkyne‐functionalized macromolecules were synthesized in a one‐pot procedure. TMPO and THF are found to polymerize in exact ratios, indicating a kinetically controlled buildup of nonrandom composition copolymers. Several of the materials show excellent compatibility with ADN, and rapid curing of the energetic polyglycidyl azide polymer (GAP) have been demonstrated through 1,3‐dipolar cycloaddition at 75°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Mechanical properties of (poly(L‐lactide‐co‐glycolide))‐based fibers coated with hydroxyapatite layer
Authors: Buczynska Joanna , Pamula Elzbieta , Blazewicz Stanislaw 
Published: April 2011

AbstractThis article presents the results of the experimental study on manufacturing and mechanical evaluation of poly(L‐lactide‐co‐glycolide) (PLGA)‐based fibers modified with ceramic nanoparticles. Study was conducted to establish the effect of biomimetic formation of apatite layers on polymeric fibers on their mechanical properties. The tensile tests were performed to determine the influence of polymer crystallinity and the presence of hydroxyapatite nanoparticles (nanoHAp) on mechanical properties of PLGA fibers coated with hydroxyapatite (HAp) layer. HAp deposits on the surfaces of the fibers precipitated from simulated body fluid (SBF). Three types of fibers coated with HAp layers were compared in mechanical tests. The results indicated that by using a biomimetic fiber coating method the mechanical properties of the fibers are affected by their crystallinity. The nanoHAp modified polymer fibers after incubation in SBF were found to have a continuous HAp layer. The layer affected the mechanical behavior (force–strain function) of the fibers from nonlinear to linear, typical of ceramic materials. The tensile modulus of the fibers with a continuous layer was found to increase with the apatite layer thickness, whereas the tensile strength decreases. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
No evidence for IL1RAPL1 involvement in selected high‐risk autism pedigrees from the AGRE data set
Authors: Allen‐Brady Kristina , Cai Guiqing , Cannon Dale , Robison Reid , McMahon William M. , Coon Hilary , Buxbaum Joseph D. 
Published: April 2011

AbstractFinding predisposition genes for Autism Spectrum Disorder (ASD) has proven challenging, and new methods are needed to aid the process. Using pedigree structure as a strategy to identify ASD predisposition genes, we previously performed a genome‐wide linkage scan of 86 selected families from the Autism Resource Exchange (AGRE) that appeared to inherit ASD in a dominant manner. We identified a suggestive linkage peak on chromosome Xp22.11‐p21.2 that encompasses the IL1RAPL1 gene, a strong candidate gene for ASD. In this follow‐up study, we sequenced the coding regions of the IL1RAPL1 gene in 14 male cases representing one case from each pedigree that showed at least nominal linkage evidence on per pedigree basis to the chromosome X region. We observed no deleterious mutations or deletions in the IL1RAPL1 gene in these 14 ASD cases. A SNP was identified in exon 2 in five cases and a variant of unknown significance was identified in intron 6 in a single case. In conclusion, coding changes of the IL1RAPL1 gene do not appear to be associated with ASD in selected AGRE families with linkage evidence to the chromosome Xp22.11‐p21.2 region. Autism Res 2011,4:293–296. © 2011 International Society for Autism Research, Wiley Periodicals, Inc.
Glyoxalase I polymorphism rs2736654 causing the Ala111Glu substitution modulates enzyme activity—implications for autism
Authors: Barua Madhabi , Jenkins Edmund C. , Chen Wenqiang , Kuizon Salomon , Pullarkat Raju K. , Junaid Mohammed A. 
Published: April 2011

AbstractAutism is a pervasive, heterogeneous, neurodevelopmental disability characterized by impairments in verbal communications, reciprocal social interactions, and restricted repetitive stereotyped behaviors. Evidence suggests the involvement of multiple genetic factors in the etiology of autism, and extensive genome‐wide association studies have revealed several candidate genes that bear single nucleotide polymorphisms (SNPs) in non‐coding and coding regions. We have shown that a non‐conservative, non‐synonymous SNP in the glyoxalase I gene, GLOI, may be an autism susceptibility factor. The GLOI rs2736654 SNP is a C→A change that causes an Ala111Glu change in the Glo1 enzyme. To identify the significance of the SNP, we have conducted functional assays for Glo1. We now present evidence that the presence of the A‐allele at rs2736654 results in reduced enzyme activity. Glo1 activity is decreased in lymphoblastoid cells that are homozygous for the A allele. The Glu‐isoform of Glo1 in these cells is hyperphosphorylated. Direct HPLC measurements of the glyoxalase I substrate, methylglyoxal (MG), show an increase in MG in these cells. Western blot analysis revealed elevated levels of the receptor for advanced glycation end products (RAGEs). We also show that MG is toxic to the developing neuronal cells. We suggest that accumulation of MG results in the formation of AGEs, which induce expression of the RAGE that during crucial neuronal development may be a factor in the pathology of autism. Autism Res 2011,4:262–270. © 2011 International Society for Autism Research, Wiley Periodicals, Inc.
Measuring the persistence length of MCF7 cell microtubules in vitro
Authors: Feizabadi Mitra Shojania , Mutafopulos Kiryako S. , Behr Adam 
Published: April 2011

AbstractThe dynamic and mechanical properties of mammalian neural microtubules have been widely studied; however, similar knowledge about these properties is limited for non‐neural microtubules, which, unlike neural microtubules, consist of different β‐tubulin isotypes. In this study, we report, for the first time, an estimated value for the persistence length of a single non‐neural microtubule polymerized from purified tubulin from human breast cancer cell lines (MCF7 tubulin). The method of measurement is based on an analysis of the local curvature of a microtubule as a result of thermal fluctuations. In parallel, we measured the persistence length of a single bovine brain microtubule under similar conditions. The results of our measurements indicate a higher value for the persistence length of MCF7 microtubules in vitro as compared to the persistence length of a neural microtubule. The difference can be associated with different β‐tubulin isotypes in the structure of MCF7 microtubules.
Ternary Cobalt–Iron Phosphide Nanocrystals with Controlled Compositions, Properties, and Morphologies from Nanorods and Nanorice to Split Nanostructures
Authors: Ye Enyi , Zhang Shuang‐Yuan , Lim Suo Hon , Bosman Michel , Zhang Zhihua , Win Khin Yin , Han Ming‐Yong 
Published: April 2011

AbstractStructural phase‐controlled formation of binary Co2P and CoP nanocrystals is achieved by reacting cobalt(II) oleate with trioctylphosphine. In the absence of oleylamine, Co2P nanowires are formed at both 290 and 320 °C. In the presence of oleylamine, Co2P nanorods are formed at 290 °C, and CoP nanorods are formed at 320 °C. With the simultaneous reaction of iron(III) oleate and cobalt(II) oleate with trioctylphosphine in the presence of oleylamine, ternary Co2P‐type cobalt–iron phosphide nanostructures are produced at both 290 and 320 °C, corresponding to rice‐shaped Co1.5Fe0.5P nanorods and split Co1.7Fe0.3P nanostructures, respectively. The controlled incorporation of iron into cobalt phosphide can alter the magnetic properties from paramagnetic binary Co2P to ferromagnetic Co2P‐type ternary cobalt–iron phosphide nanostructures. Meanwhile, the time‐dependent morphological evolution from small nanodots/nanorods, through seeded growth to unique split nanostructures is demonstrated in one‐pot reaction at 320 °C.
Identification of retinotectal projection pathway in the deep tectal laminae in the chick
Authors: Omi Minoru , Harada Hidekiyo , Nakamura Harukazu 
Published: April 2011

AbstractThe optic tectum is a visual center of nonmammalian vertebrates that receives retinal fibers in a retinotopic manner. It has been accepted that retinal fibers project to some superficial laminae of the tectum, but do not go through lamina g of stratum griseum et fibrosum superficiale (SGFS). By a novel fiber‐tracing method, we found a novel pathway of retinal fibers that run through deep laminae of the tectum. The retinal fibers that would run through the newly identified pathway first run caudally along the medial edge after invading the tectum, turn laterally, and extend toward the lateral side through the deep pathway. The deep pathway runs through stratum album centrale and stratum fibrosum periventriculare. The fibers that run through the deep pathway do not enter the stratum opticum, where the conventional retinal fibers run. As development proceeds, these fibers decrease and disappear by the adult stage. By the new method, we found that some of the conventional retinal fibers transiently run through lamina g of SGFS and invade laminae h/i. In conclusion, we found distinct but transient retinal fiber pathway in the deep tectal laminae, which have not been thought to be retinorecipient. J. Comp. Neurol. 519:2615–2621, 2011. © 2011 Wiley‐Liss, Inc.
Phenotypic changes in calbindin D28K immunoreactivity in the hippocampus of Fmr1 knockout mice
Authors: Real M. Angeles , Simón M. Pilar , Heredia Raúl , de Diego Yolanda , Guirado Salvador 
Published: April 2011

AbstractFragile X syndrome (FXS), the most prevalent form of inherited mental retardation, is caused by the lack of FMRP (fragile mental retardation protein) as a result of the transcriptional silencing of the FMR1 gene. Here we analyze the immunohistochemical expression of the calbindin D28K protein in the hippocampus of Fmr1 knockout (KO) mice and compare it with that of their wildtype (WT) littermates. The spatial distribution pattern of calbindin‐immunoreactive cells in the hippocampus was similar in WT and KO mice but for each age studied (ranging from 3.5–8 months) the dentate gyrus of Fmr1‐KO mice showed a significant reduction in calbindin‐immunoreactive granule cells. Also, the number of calbindin‐immunoreactive cells was reduced in the CA1 pyramidal layer in KO mice compared to their WT littermates. In addition, Frm1‐KO mice showed a group of calbindin‐immunoreactive cells located only in the left CA3b subregion that was only sometimes observed in WT mice. Overall, the absence of FMRP results in a dysregulation of the calbindin protein expression in the hippocampus. This dysregulation is cell type‐ and time‐dependent and as a consequence key elements of the hippocampal trisynaptic circuitry may lack calbindin in critical periods for normal memory/learning abilities to be achieved and may explain some of the FXS symptoms observed in the Fmr1‐KO mouse model. J. Comp. Neurol. 519:2622–2636, 2011. © 2011 Wiley‐Liss, Inc.
The Evolution of Bonding and Thermodynamic Properties of Boron‐Doped Small Carbon Clusters: An Ab Initio Study
Authors: Saloni Julia , Kadłubański Paweł , Roszak Szczepan , Majumdar D. , Hill Glake , Leszczynski Jerzy 
Published: April 2011

AbstractTheoretical studies on BCn (n=1–6) clusters are carried out using density functional theory, Møller–Plesset second‐order perturbation theory (MP2), coupled‐cluster calculations including up to triple excitations (CCSD(T)), and higher‐level approaches. All possible isomers depending on the positions of the boron atom are generated and the lowest‐energy isomers are determined for doublet and quartet electronic states. The three potential evolution paths of the clusters are determined as a function of their size. The energetic and electronic consequences for the increased size of structures differ significantly, which leads to representatives of the ground electronic state from different structural groups. The ab initio calculated thermal functions allow enhancements to the available atomization energies and improve the agreement between the calculated and experimental heat content.