bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular mobility of nitroxide spin probes in glassy polymers: Models of the complex motion of spin probes
Authors: Chernova Daria A. , Vorobiev Andrey Kh. 
Published: February 2011

AbstractThe rotational mobility of molecules in glassy polymers was investigated by quantitative simulations of electron spin resonance spectra of nitroxide spin probes with molecules of different sizes. The motional models were determined unambiguously when the experimental and calculated spectra coincided within the level of experimental error. Temperature ranges in which different motional models were applicable were determined. Quasi‐librational movements and the distribution of rotational mobility were found to be necessary for the qualitative description of spin‐probe mobility in glassy polymers. The quantitative and empirical characteristics of rotational mobility were examined. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Catalyst‐free preparation of polyhedral oligomeric silsesquioxanes containing Organic–Inorganic hybrid mesoporous nanocomposites
Authors: Qin Yuancheng , Zhu Fanghua , Luo Meiming , Zhang Lin 
Published: February 2011

AbstractA catalyst‐free, one‐pot method of preparing novel polyhedral oligomeric silsesquioxanes (POSS) containing organic–inorganic hybrid mesoporous nanocomposite at room temperature is reported. Nitrogen sorption analyses gave us a specific surface area of 500.931 m2/g with a pore volume of 0.563 mL/g and an average pore size of 3.84 nm. The combined results of Fourier transform infrared and solid 29Si‐NMR spectroscopy clearly show that the POSS building block was successfully woven into the porous nanostructure without obvious alteration of the characteristics and structure. The material showed good thermal stability. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Blend toughening of poly(vinyl chloride) by chlorinated polyethylene/hydroxy ethyl acrylate graft copolymer
Authors: Du Zhuang , Xu Chao , Zhao Zhiqiang , Zhao Jiruo , Feng Ying 
Published: February 2011

AbstractBlends of poly(vinyl chloride) (PVC) and chlorinated polyethylene‐chlorinating graft‐hydroxy ethyl acrylate copolymer (CPE‐cg‐HEA) were prepared. CPE‐cg‐HEA, as toughening modifier, is a graft copolymer with a backbone of chlorinated polyethylene (CPE) and branched chains of poly(2‐hydroxy ethyl acrylate) (PHEA). Compared with PVC/CPE, CPE‐cg‐HEA demonstrated better toughening effects on the blends in the tensile strength, elongation at break, and impact strength. Particularly, compared to PVC/CPE blends PVC/CPE‐cg‐HEA blends with 5 phr CPE‐cg‐HEA showed an increases in the tensile and notched impact strength by 17.9 and 30% respectively, compared to the PVC/CPE blends. Differential scanning calorimetry analysis indicated that the miscibility of PVC/CPE‐cg‐HEA was better than that of PVC/CPE. An analysis of morphological structure showed that the grafting component of PHEA onto CPE promoted amalgamation between the primary particles of PVC and CPE‐cg‐HEA. Further research suggested that the toughening mechanism of the PVC/CPE‐cg‐HEA blends was different from that of the PVC/CPE blends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Mechanical properties of 1,2,4,5‐benzene tetra carboxylic chitosan‐filled chitosan biocomposites
Authors: Julkapli Nurhidayatullaili Muhd , Ahmad Zulkifli , Akil Hazizan Md 
Published: February 2011

AbstractThe degree of matrix‐filler interaction plays an important role in determining the mechanical properties of biocomposite materials. To produce highly compatible chitosan biocomposites, 1,2,4,5‐benzene tetra carboxylic chitosan (BTC) was used as a filler to reinforce a chitosan matrix (Cs), because the similar backbone structure of Cs and BTC filler is expected to increase the compatibility of the biocomposite. The mechanical properties of these biocomposites were investigated under tension and tearing mode. Introduction of BTC filler (at 0, 2, 4, 6, 8, and 10 wt%) provided dramatic increments in σR and E values, but the observed values of εR and K correlated negatively to similar levels of BTC filler. Morphological results demonstrate that the breaking surfaces of biocomposites form rugged deformation lines, resulting in high σK values of the biocomposites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effects of charge trapping on the electrical conductivity of low‐density Polyethylene–Carbon black composites
Authors: Dudić D. , Škipina B. , Dojčilović J. , Novaković L. , Kostoski D. 
Published: February 2011

AbstractElectrical conductivities of low‐density polyethylene (LDPE)–carbon black (CB) composites were studied using high resistance meter at room temperature (DC conductivity) and dielectric spectroscopy (AC conductivity) in the frequency range between 90 kHz and 13 MHz and temperature range from 120 to 355 K. DC measurements revealed a percolation threshold at about 20 wt % of CB content, whereas AC measurements show two conductivity peaks at about 15% and 23% of CB content. The presence of two percolation thresholds was attributed to different dispersions of CB particles in structural inhomogeneities of LDPE. The experimental data were analyzed using the model of Efros and Shklovskii, which describes the critical behavior of a complex conductivity using critical indexes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Strain‐induced crystallization behavior of polychloroprene rubber
Authors: Zhang Peng , Huang Guangsu , Qu Liangliang , Nie Yijing , Weng Gengsheng , Wu Jinrong 
Published: February 2011

AbstractThe crystallization behavior of polychloroprene rubber (CR) has been studied in this work. Differential scanning calorimetry (DSC) was applied to characterize the crystallization behavior. And X‐ray diffraction was applied to determine the impact of crosslinking on the crystallization of CR. Synchrotron X‐ray diffraction (SXRD) method was applied to study the dynamic crystalline behavior. On the basis of the experimental results, it is found that crosslinking will hamper the crystallization of CR while large strain can restore this course. And this is in accord with the Mooney‐Rivlin analysis result. Detailed discussion was offered circling around this phenomenon. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Evaluation of nonisothermal crystallization kinetic models for linear poly(phenylene sulfide)
Authors: Liu Pengqing , Hu An , Wang Sheng , Shi Meiwu , Ye Guangdou , Xu Jianjun 
Published: February 2011

AbstractThe nonisothermal crystallization kinetics of linear Poly(phenylene sulfide) (PPS) was studied with differential scanning calorimetry. Ozawa theory, Jeziorny model, and Mo equation were applied to describe the crystallization kinetics and to determine the crystallization parameters and mechanism of the linear PPS resin. The crystallization activation energies were also calculated using Kissinger formula and Flynn‐Wall‐Ozawa equation, respectively. According to the Ozawa model, it is found that instantaneous nucleation takes place during crystallization of PPS; the Ozawa exponent m is 3 in initial stage of crystallization; as the crystallization temperature decreases, the value of m reduces, and the growth rate of crystal almost keeps a constant. The Avrami exponent n obtained from Jeziorny model fluctuate around 1.84. Based on the Jeziorny model, the crystallization rate increases with increasing the cooling rate, but it does not change any longer when the cooling rate rise to a certain value. Mo equation also exhibits great advantages in treating the nonisothermal crystallization kinetics of PPS. The activation energy E of nonisothermal crystallization process of PPS is calculated to be −162.73 kJ/mol by the Kissinger formula, and the mean value of E determined by Flynn‐Wall‐Ozawa equation is −152.40 kJ/mol. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis of double silylene‐bridged binuclear metallocenes and their cooperation effect during ethylene polymerization and ethylene/1‐hexene copolymerization
Authors: Mi Puke , Xu Sheng , Qu Liangduan , Deshun Zhang , Qian Chen , Sihan Wang 
Published: February 2011

AbstractNovel double silylene‐bridged binuclear Group 4 metallocene complexes [(η5‐C5H5)MCl2]2[μ, μ‐(SiMe2)2 (η5‐RC5H2)2] [R = Me, M = Zr (1); R = allyl, M = Ti (2); R = allyl, M = Zr (3); R = nBu, M = Ti (5); R = Me3Si, M = Zr (6)] and [(η5‐CH3C5H4)ZrCl2]2[μ, μ‐(SiMe2)2 (η5‐allyl‐C5H2)2, (4)] were synthesized by the reaction of CpMCl3 (M = Ti, Zr) with [μ, μ‐(SiMe2)2 (η5‐RC5H2)2]2‐ (L2‐) in THF, and they were all well characterized by 1H‐NMR, MS, and EA. When activated with methylaluminoxane (MAO), this series complexes are active catalysts for Ethylene polymerization (Complex 3, 3.86 × 106 g‐PE/mol‐M h, Al/Zr = 500) and copolymerization of ethylene with 1‐hexene (Complex 3,30.87 × 105 g‐polymer/mol‐M h, 1‐hexene content in polymer 2.34 mol %, Al/Zr = 1000). The result of polymerization implies that there is a cooperative effect between the two metals in the double‐bridged binuclear molecules. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
New deep blue light emitting copolymer containing fluorene, carbazole, and dialkoxynaphthalene
Authors: Kang Hyun Hee , Kang Moon Seong , Oh Dae Hwan , Lee Dong Hee , Shin Dong‐Cheol , Kwon Soon‐Ki , Kim Yun‐Hi 
Published: February 2011

AbstractWe synthesized the new copolymer, which was composed of dialkoxy naphthalene, N‐alkylcarbazole, and fluorine, by Suzuki coupling reaction. The resulting copolymer was soluble in common organic solvents and showed the weight‐average molecular weight (MW) of 288,000 with a polydispersity index of 2.56. Cyclic voltammetry and UV–vis study revealed that the HOMO energy level and optical band gap of copolymer was 5.66 and 3.03 eV, respectively. The ITO/PEDOT/polymer/LiF/Al device emits bright deep blue light with a maximum peak around 422 nm. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
A Genome‐Wide Linkage Scan for Quantitative Trait Loci Influencing the Craniofacial Complex in Humans (Homo sapiens sapiens)
Authors: Sherwood Richard J. , Duren Dana L. , Mahaney Michael C. , Blangero John , Dyer Thomas D. , Cole Shelley A. , Czerwinski Stefan A. , Chumlea WM. Cameron , Siervogel Roger M. , Choh Audrey C. , Nahhas Ramzi W. , Lee Miryoung , Towne Bradford 
Published: February 2011

AbstractThe genetic architecture of the craniofacial complex has been the subject of intense scrutiny because of the high frequency of congenital malformations. Numerous animal models have been used to document the early development of the craniofacial complex, but few studies have focused directly on the genetic underpinnings of normal variation in the human craniofacial complex. This study examines 80 quantitative traits derived from lateral cephalographs of 981 participants in the Fels Longitudinal Study, Wright State University, Dayton, Ohio. Quantitative genetic analyses were conducted using the Sequential Oligogenic Linkage Analysis Routines analytic platform, a maximum‐likelihood variance components method that incorporates all familial information for parameter estimation. Heritability estimates were significant and of moderate to high magnitude for all craniofacial traits. Additionally, significant quantitative trait loci (QTL) were identified for 10 traits from the three developmental components (basicranium, splanchnocranium, and neurocranium) of the craniofacial complex. These QTL were found on chromosomes 3, 6, 11, 12, and 14. This study of the genetic architecture of the craniofacial complex elucidates fundamental information of the genetic architecture of the craniofacial complex in humans. Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.
Aerobic Oxidations Catalyzed by Colloidal Nanogold
Authors: Tsukuda Tatsuya , Tsunoyama Hironori , Sakurai Hidehiro 
Published: February 2011

AbstractRecently, dispersions of gold nanoclusters in liquid media (colloidal nanogold) have been extensively used as quasi‐homogeneous catalysts for various aerobic oxidation reactions. This review describes recent progress in such reactions, with a focus on our comprehensive studies on gold clusters (<2 nm) stabilized by poly(N‐vinyl‐2‐pyrrolidone) and their participation in oxidation reactions of alcohols, α‐hydroxylation reactions of benzylic ketones, and homocoupling reactions of organoboronates, as well as formal Lewis acidic reactions, such as intramolecular hydroalkoxylation and hydroamination reactions of nonactivated alkenes. Mechanistic studies have shown that a partial electron transfer from the gold clusters to O2 generates superoxide‐ or peroxide‐like species and Lewis acidic centers, both of which play essential roles in the catalytic reactions.
Synthesis, Photophysical, and Two‐Photon Absorption Properties of Elongated Phosphane Oxide and Sulfide Derivatives
Authors: Alain‐Rizzo Valérie , Drouin‐Kucma Delphine , Rouxel Cédric , Samb Issa , Bell Jérémy , Toullec Patrick Y. , Michelet Véronique , Leray Isabelle , Blanchard‐Desce Mireille 
Published: February 2011

AbstractA series of rod‐shaped and related three‐branched push–pull derivatives containing phosphane oxide or phosphane sulfide (PO or PS)—as an electron‐withdrawing group conjugated to electron‐donating groups, such as amino or ether groups, with a conjugated rod consisting of arylene–vinylene or arylene–ethynylene building blocks—were prepared. These compounds were efficiently synthesized by a Grignard reaction followed by Sonogashira coupling. Their photophysical properties including absorption, emission, time‐resolved fluorescence, and two‐photon absorption (TPA) were investigated with special attention to structure–property relationships. These fluorophores show high fluorescence quantum yields and solvent‐dependent experiments reveal that efficient intramolecular charge transfer occurs upon excitation, thereby leading to highly polar excited states, the polarity of which can be significantly enhanced by playing on the end groups and conjugated linker. Rod‐shaped and related three‐branched systems show similar fluorescence properties in agreement with excitation localization on one of the push–pull branches. By using stronger electron donors or replacing the arylene–ethynylene linkers with an arylene–vinylene one induces significant redshifts of both the low‐energy one‐photon absorption and TPA bands. Interestingly, a major enhancement in TPA responses is observed, whereas OPA intensities are only weakly affected. Similarly, phosphane oxide derivatives show similar OPA responses than the corresponding sulfides but their TPA responses are significantly larger. Finally, the electronic coupling between dipolar branches promoted by common PO or PS acceptor moieties induces either slight enhancement of the TPA responses or broadening of the TPA band in the near infrared (NIR) region. Such behavior markedly contrasts with triphenylamine‐core‐mediated coupling, which gives evidence for the different types of interactions between branches.
Opportunities for yeast metabolic engineering: Lessons from synthetic biology
Authors: Krivoruchko Anastasia , Siewers Verena , Nielsen Jens 
Published: February 2011

AbstractConstant progress in genetic engineering has given rise to a number of promising areas of research that facilitated the expansion of industrial biotechnology. The field of metabolic engineering, which utilizes genetic tools to manipulate microbial metabolism to enhance the production of compounds of interest, has had a particularly strong impact by providing new platforms for chemical production. Recent developments in synthetic biology promise to expand the metabolic engineering toolbox further by creating novel biological components for pathway design. The present review addresses some of the recent advances in synthetic biology and how these have the potential to affect metabolic engineering in the yeast Saccharomyces cerevisiae. While S. cerevisiae for years has been a robust industrial organism and the target of multiple metabolic engineering trials, its potential for synthetic biology has remained relatively unexplored and further research in this field could strongly contribute to industrial biotechnology. This review also addresses are general considerations for pathway design, ranging from individual components to regulatory systems, overall pathway considerations and whole‐organism engineering, with an emphasis on potential contributions of synthetic biology to these areas. Some examples of applications for yeast synthetic biology and metabolic engineering are also discussed.
A Strategy for clone selection under different production conditions
Authors: Legmann Rachel , Benoit Brian , Fedechko Ronald W. , Deppeler Cynthia L. , Srinivasan Sriram , Robins Russell H. , McCormick Ellen L. , Ferrick David A. , Rodgers Seth T. , Russo A. Peter 
Published: February 2011

AbstractTop performing clones have failed at the manufacturing scale while the true best performer may have been rejected early in the screening process. Therefore, the ability to screen multiple clones in complex fed‐batch processes using multiple process variations can be used to assess robustness and to identify critical factors. This dynamic ranking of clones' strategy requires the execution of many parallel experiments than traditional approaches. Therefore, this approach is best suited for micro‐bioreactor models which can perform hundreds of experiments quickly and efficiently. In this study, a fully monitored and controlled small scale platform was used to screen eight CHO clones producing a recombinant monoclonal antibody across several process variations, including different feeding strategies, temperature shifts and pH control profiles. The first screen utilized 240 micro‐bioreactors were run for two weeks for this assessment of the scale‐down model as a high‐throughput tool for clone evaluation. The richness of the outcome data enable to clearly identify the best and worst clone as well as process in term of maximum monoclonal antibody titer. The follow‐up comparison study utilized 180 micro‐bioreactors in a full factorial design and a subset of 12 clone/process combinations was selected to be run parallel in duplicate shake flasks. Good correlation between the micro‐bioreactor predictions and those made in shake flasks with a Pearson correlation value of 0.94. The results also demonstrate that this micro‐scale system can perform clone screening and process optimization for gaining significant titer improvements simultaneously. This dynamic ranking strategy can support better choices of production clones. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011
Percutaneous intervention of a thrombotic‐occluded saphenous vein graft successfully treated using the undersized stent approach to prevent distal embolization
Authors: Maluenda Gabriel , Alfonso Fernando , Pichard Augusto D. 
Published: February 2011

AbstractPercutaneous intervention carries a higher risk of distal embolization and poorer outcome in saphenous vein grafts (SVG) than in native coronary vessels. Embolic protection devices (EPD) have demonstrated value in decreasing the risk of embolization and post‐procedural enzymes elevation after SVG intervention. Although there is ample evidence to support the routine use of EPD for SVG interventions, frequently those devices are not utilized or cannot be used because of technical reasons. As we previously reported, the “undersized stenting” approach seems to be an attractive strategy when EPD cannot be used. We present a case with severe SVG degeneration that illustrates the feasibility of this strategy. © 2011 Wiley‐Liss, Inc.
An expression for the voltage response of a current‐excited fractance device based on fractional‐order trigonometric identities
Authors: Radwan A. G. , Elwakil A. S. 
Published: February 2011

SUMMARYWe report a closed‐form expression of the voltage response of a current‐excited fractance device. The derived simple expression is made possible following the introduction of the generalized sine and cosine functions (rmsinα(t) and cosα(t)), which are valid on any fractional‐order surface and tend to the normal sin(t) and cos(t) at α = 1 or asymptotically as t→∞. Copyright © 2011 John Wiley & Sons, Ltd.
Abdichtung erdberührter Bauteile: Kombiabdichtung
Authors: Korff Hans‐Klaus 
Published: February 2011

AbstractJede Abdichtung von Bauteilen oder Bauwerken gegen hydrostatisch drückendes Wasser muss wannenförmig erfolgen. Dies gilt sowohl für Wasser, das von außen als auch für solches, das von innen Druck auf ein Bauwerk ausübt. Der letztgenannte Bereich betrifft Schwimm‐ und sonstige Becken für die Aufnahme von Wasser und anderen Flüssigkeiten. Die nachstehenden Ausführungen beschränken sich aber auf das von außen auf erdberührte Bauteile/Bauwerke drückende Wasser im Hochbau und hier schwerpunktmäßig auf aufstauendes Sickerwasser, das zeitweise einwirkt. Bei diesem Lastfall wird in der Praxis schon heute in den meisten Fällen eine Kombinationslösung (Kombiabdichtung) gewählt, die auch im Mittelpunkt der nachstehenden Betrachtungen steht.Außerdem soll auf ein Problem hingewiesen werden, das besonders bei Schadensfällen immer wieder zu unterschiedlichen Auslegungen führt: die Frage, welche Schichtdicke bei Abdichtungen mit kunststoffmodifizierten Bitumendickbeschichtungen (KMB) noch zulässig ist, wenn die Baugrube bereits mehrere Monate oder gar Jahre verfüllt war und die Abdichtung — meist wegen eines Schadens — freigelegt werden muss. In der Regel wird dabei auch die noch vorhandene Schichtdicke der KMB festzustellen sein. Oder anders ausgedrückt, wie weit darf die Dicke der KMB auch nach Jahren gegenüber der bei dem Einbau erforderlichen Trockenschichtdicke abgenommen haben.
Earthquake fault‐induced surface rupture—A hybrid strong ground motion simulation technique and discussion for structural design
Authors: Tahghighi Hossein 
Published: February 2011

AbstractUnique to the near‐source region of a large earthquake is the occurrence of strong impulsive ground motion and surface faulting referred to as ‘fling‐step’ motion. The objective of this study is to synthesize broad‐band time histories over a wide range of frequencies by characterizing rupture directivity and fling effects from the comprehensive strong motion database of the near‐fault Chi‐Chi event. To aid in the generation of these special types of ground motions, a hybrid modeling technique is introduced based on the stochastic finite‐fault radiation method and an efficient analytical approach to incorporate the observed low‐frequency features in the records close to the ruptured fault. The results show that the overall agreement among the developed hybrid methodology and recorded waveforms and response spectra is quite satisfying. A brief discussion on the design of infrastructures near seismic fault is also included. Copyright © 2011 John Wiley & Sons, Ltd.
A Case Series Investigating Distinct Neuropsychological Profiles in Children and Adolescents with Anorexia Nervosa
Authors: Rose Mark , Frampton Ian , Lask Bryan 
Published: February 2011

AbstractA number of specific deficits in neuropsychological functioning in anorexia nervosa (AN) have been identified. However, it is not known whether these specific deficits cluster together to form one or more clear neuropsychological profiles. We present a case series of nine participants who were recruited as part of a wider, ongoing investigation of the neuropsychological profile of eating disorders (the Ravello Profile). Results show that there was a wide range of different neuropsychological profiles at initial assessment. This suggests a spectrum of neuropsychological strengths and weaknesses that would otherwise be masked in a cohort analysis. It is anticipated that factor and cluster analytic studies will establish one or more common profiles of neuropsychological deficits in AN. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.