bluuebunny/crossref_metadata_2025_split huggingface dataset:
IN SITU POLYMERIZATION OF FE3O4/POLYURETHANE NANOCOMPOSITES WITH HIGH PERFORMANCE
Authors: Yao Junru , Hou Chunling , Yu Hailin , Sun Youyi , Gao Li , Liu Yaqing 
Published: May 2016

ABSTRACT
The stable Fe3O4 magnetorheological fluids were first prepared by coprecipitation method without using any surfactants and characterized by X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer. The polyurethane elastomers were further polymerized in the presence of stable Fe3O4 magnetorheological fluids. Furthermore, the effect of Fe3O4 loading on mechanical, magnetic, thermal, electrical, and microwave-absorbing properties of the polyurethane elastomers were systematically investigated. The results indicated that the synthesis process and Fe3O4 loading had great effects on the properties of polyurethane elastomers. A synthesis-based in situ polymerization method using Fe3O4 magnetorheological fluids instead of dry powder could improve the dispersion of Fe3O4 nanoparticles in the polyurethane matrix. The Fe3O4/polyurethane nanocomposites showed high mechanical, magnetic, thermal, electrical, and microwave-absorbing properties at a low loading of 2 wt%, and could potentially be used for a wide range of applications.
TOWARD REPLACEMENT OF PETROLEUM OILS BY MODIFIED SOYBEAN OILS IN ELASTOMERS
Authors: Li Jiaxi , Isayev Avraam I. , Ren Xiaofeng , Soucek Mark D. 
Published: May 2016

ABSTRACT
Precipitated silica- and carbon black (CB)-filled styrene-butadiene rubber (SBR) compounds and vulcanizates containing naphthenic oil (NO), soybean oil (SO), and modified soybean oil (MSO) were studied. Gel fraction; crosslink density; bound rubber fraction; curing behavior; and thermal, mechanical, and dynamic properties were compared. Interaction between SO, MSO, and silane coupling agent was also studied. It was shown that the incorporation of SO and MSO had similar effects in both silica- and CB-filled SBR compounds and vulcanizates. SO and MSO were found to consume curatives leading to a lower crosslink density and improved thermal stability of compounds and vulcanizates. In comparison with NO, MSO was found to increase the elongation at break and tensile strength, and the values of tan δ at 10 °C and 60 °C predict an increase of the wet traction performance and the rolling resistance to decrease the modulus and abrasion resistance. After adjusting the recipe, the modulus and abrasion resistance of the silica- and CB-filled SBR/MSO vulcanizates were tremendously increased, and the silica-filled SBR/MSO vulcanizates exhibited a better wet traction performance, a lower rolling resistance, and a better abrasion resistance simultaneously than the silica-filled SBR/NO vulcanizate.
Aperçu de la pratique de la science ouverte dans les universités francophones au Québec
Authors: Emond Nancy 
Published: May 2016

Participer à l’avènement de sociétés du savoir fait désormais partie des missions que se donnent plusieurs institutions scientifiques dans le monde. Pour ce faire, l’une des nouvelles tendances qui se dessinent est celle de la pratique de la science ouverte, à savoir une science collaborative, participative, voire interdisciplinaire. Cette pratique s’effectue par divers moyens : recherche axée sur les besoins des communautés, partenariats avec des acteurs des sphères publique et privée, diffusion et accessibilité gratuite aux connaissances scientifiques et interconnexion entre des chercheuses et chercheurs de différentes universités et disciplines. Comment le Québec s’inscrit-il dans ce nouveau mouvement ? Cet article a pour objectif de dresser un portrait de la situation qui prévaut au Québec dans huit universités francophones et d’amorcer une réflexion sur les forces et les faiblesses du système scientifique universitaire québécois dans sa participation à l’émergence de sociétés du savoir.
Un poids décisif? L’influence du Québec sur les interventions militaires canadiennes
Authors: Massie Justin , Haglund David G. 
Published: May 2016

Parmi les débats les plus persistants dans l’étude de la politique étrangère et de sécurité du Canada se trouve l’influence du Québec sur son élaboration et son exécution. Certains estiment que la minorité nationale francophone jouit d’une influence disproportionnée, alors que d’autres jugent plutôt que les valeurs et les intérêts du Québec sont marginalisés. Qu’en est-il exactement ? Cet article offre une analyse contrefactuelle de la question en s’attardant plus spécifiquement à la participation militaire canadienne aux coalitions d’États volontaires dirigées par les États-Unis. Nous examinons deux études de cas qui ont largement dominé les relations canado-américaines contemporaines, c’est-à-dire la guerre en Afghanistan et l’invasion anglo-américaine de l’Irak. Il ressort de notre analyse que, si le Québec peut se vanter de sa spécificité en matière de sécurité internationale, il est loin d’être avéré qu’une fédération canadienne sans le Québec aurait adopté des positions fondamentalement différentes de celles qui furent adoptées.
Evaluation of disorder introduced by electrolyte gating through transport measurements in graphene
Authors: Browning Andrew , Kumada Norio , Sekine Yoshiaki , Irie Hiroshi , Muraki Koji , Yamamoto Hideki 
Published: May 2016

Abstract
We evaluate the degree of disorder in electrolyte-gating devices through transport measurements in graphene. By comparing the mobility in ion- and standard metal-gated devices, we show that the deposition of the ionic liquid introduces charged impurities that limit the mobility in graphene to 3 × 103 cm2 V−1 s−1. At higher temperatures (>50 K), phonons in the ionic liquid further reduce the mobility, making its upper limit 2 × 103 cm2 V−1 s−1 at room temperature. Since the degree of disorder is independent of the base material, these results are valuable for understanding disorder effects in general devices using electrolyte gating.
CO2 non‐LTE limb emissions in Mars' atmosphere as observed by OMEGA/Mars Express
Authors: Piccialli A. , López‐Valverde M. A. , Määttänen A. , González‐Galindo F. , Audouard J. , Altieri F. , Forget F. , Drossart P. , Gondet B. , Bibring J. P. 
Published: May 2016

AbstractWe report on daytime limb observations of Mars upper atmosphere acquired by the OMEGA instrument on board the European spacecraft Mars Express. The strong emission observed at 4.3 μm is interpreted as due to CO2 fluorescence of solar radiation and is detected at a tangent altitude in between 60 and 110 km. The main value of OMEGA observations is that they provide simultaneously spectral information and good spatial sampling of the CO2 emission. In this study we analyzed 98 dayside limb observations spanning over more than 3 Martian years, with a very good latitudinal and longitudinal coverage. Thanks to the precise altitude sounding capabilities of OMEGA, we extracted vertical profiles of the non‐local thermodynamic equilibrium (non‐LTE) emission at each wavelength and we studied their dependence on several geophysical parameters, such as the solar illumination and the tangent altitude. The dependence of the non‐LTE emission on solar zenith angle and altitude follows a similar behavior to that predicted by the non‐LTE model. According to our non‐LTE model, the tangent altitude of the peak of the CO2 emission varies with the thermal structure, but the pressure level where the peak of the emission is found remains constant at ∼0.03 ± 0.01 Pa, . This non‐LTE model prediction has been corroborated by comparing SPICAM and OMEGA observations. We have shown that the seasonal variations of the altitude of constant pressure levels in SPICAM stellar occultation retrievals correlate well with the variations of the OMEGA peak emission altitudes, although the exact pressure level cannot be defined with the spectroscopy for the investigation of the characteristics of the atmosphere of Venus (SPICAM) nighttime data. Thus, observed changes in the altitude of the peak emission provide us information on the altitude of the 0.03 Pa pressure level. Since the pressure at a given altitude is dictated by the thermal structure below, the tangent altitude of the peak emission represents then an important piece of information of the atmosphere, of great value for validating general circulation models. We thus compared the altitude of OMEGA peak emission with the altitude of the 0.03 Pa level predicted by the Laboratoire de météorologie dynamique (LMD)‐Mars global circulation model and found that the peak emission altitudes from OMEGA present a much larger variability than the tangent altitude of the 0.03 Pa level predicted by the general circulation model. This variability could be possibly due to unresolved atmospheric waves. Further studies using this strong CO2 limb emission data are proposed.
Increased rates of large‐magnitude explosive eruptions in Japan in the late Neogene and Quaternary
Authors: Mahony S. H. , Sparks R. S. J. , Wallace L. M. , Engwell S. L. , Scourse E. M. , Barnard N. H. , Kandlbauer J. , Brown S. K. 
Published: May 2016

AbstractTephra layers in marine sediment cores from scientific ocean drilling largely record high‐magnitude silicic explosive eruptions in the Japan arc for up to the last 20 million years. Analysis of the thickness variation with distance of 180 tephra layers from a global data set suggests that the majority of the visible tephra layers used in this study are the products of caldera‐forming eruptions with magnitude (M) > 6, considering their distances at the respective drilling sites to their likely volcanic sources. Frequency of visible tephra layers in cores indicates a marked increase in rates of large magnitude explosive eruptions at ∼8 Ma, 6–4 Ma, and further increase after ∼2 Ma. These changes are attributed to major changes in tectonic plate interactions. Lower rates of large magnitude explosive volcanism in the Miocene are related to a strike‐slip‐dominated boundary (and temporary cessation or deceleration of subduction) between the Philippine Sea Plate and southwest Japan, combined with the possibility that much of the arc in northern Japan was submerged beneath sea level partly due to previous tectonic extension of northern Honshu related to formation of the Sea of Japan. Changes in plate motions and subduction dynamics during the ∼8 Ma to present period led to (1) increased arc‐normal subduction in southwest Japan (and resumption of arc volcanism) and (2) shift from extension to compression of the upper plate in northeast Japan, leading to uplift, crustal thickening and favorable conditions for accumulation of the large volumes of silicic magma needed for explosive caldera‐forming eruptions.
Morphology and possible origins of near‐range oblique HF backscatter at high and midlatitudes
Authors: Ponomarenko Pavlo, V. , Iserhienrhien Blessing , St.‐Maurice Jean‐Pierre 
Published: May 2016

AbstractHigh‐frequency radars (HF, ∼10–20 MHz) forming the Super Dual Auroral Radar Network (SuperDARN) regularly observe returns from very close ranges of ≤300–400 km (near‐range echoes, NREs). These echoes are conventionally attributed to backscatter from meteor trails, but other sources of NRE have been invoked, including polar mesospheric summer echoes (PMSE), and non‐field‐aligned E region irregularities leading to high‐aspect ionospheric returns. In order to relate NRE to a particular mechanism, it is essential to establish beforehand their spatiotemporal trends with respect to season, local time, and latitude. Systematic information of this kind is generally lacking from the literature, so we attempt to fill the gap by performing a statistical analysis of such echoes observed by five radars covering midlatitudes to polar latitudes over all seasons and local times. We detected two major echo populations which were observed at each radar site: (i) a nightside‐early morning returns representing the well‐known meteor backscatter and (ii) a midsummer population centered near the local noon. At high latitudes the summer daytime echoes are usually interpreted as PMSE, but the observed population extends to much lower latitudes and is centered well above the conventional PMSE height range. We hypothesize that this population could be related to neutral turbulence in the lower E region. In addition, there was a pronounced evening population restricted to the auroral region which we provisionally attribute to irregularities generated by the precipitating energetic particles and strong electric fields.
Transesterification Reactions Catalyzed by a Recyclable Heterogeneous Zinc/Imidazole Catalyst
Authors: Nakatake Daiki , Yazaki Ryo , Matsushima Yoshimasa , Ohshima Takashi 
Published: May 2016

AbstractWe report the development of a universal and recyclable heterogeneous zinc/imidazole catalyst. The catalyst is recoverable through simple filtration and can be reused at least five times, retaining its catalytic activity. Leached zinc species were not responsible for the observed catalysis based on the hot filtration test and ICP‐MS analysis. The heterogeneous zinc catalyst also promotes chemoselective transesterification over amidation.magnified image
Of Poisons and Antidotes in Polypropylene Catalysis
Authors: Yu Yue , Busico Vincenzo , Budzelaar Peter H. M. , Vittoria Antonio , Cipullo Roberta 
Published: May 2016

AbstractQuenched‐flow studies of MgCl2‐supported Ziegler–Natta catalysts were combined for the first time with 13C NMR fingerprinting of the nascent polymer and conclusively proved that, depending on the catalyst formulation, propene polymerization can be slowed down significantly by the occurrence of the few regiodefects (2,1 monomer insertions), changing active sites into dormant sites. Catalysts modified with ethylbenzoate show little dormancy. The more industrially relevant phthalate based catalysts, instead, are highly dormant and require the presence of H2 to counteract the deleterious effect of this self‐poisoning on productivity and stereoselectivity.
Elucidation of the Covalent and Tertiary Structures of Biologically Active Ts3 Toxin
Authors: Dang Bobo , Kubota Tomoya , Mandal Kalyaneswar , Correa Ana M. , Bezanilla Francisco , Kent Stephen B. H. 
Published: May 2016

AbstractTs3 is an alpha scorpion toxin from the venom of the Brazilian scorpion Tityus serrulatus. Ts3 binds to the domain IV voltage sensor of voltage‐gated sodium channels (Nav) and slows down their fast inactivation. The covalent structure of the Ts3 toxin is uncertain, and the structure of the folded protein molecule is unknown. Herein, we report the total chemical synthesis of four candidate Ts3 toxin protein molecules and the results of structure–activity studies that enabled us to establish the covalent structure of biologically active Ts3 toxin. We also report the synthesis of the mirror image form of the Ts3 protein molecule, and the use of racemic protein crystallography to determine the folded (tertiary) structure of biologically active Ts3 toxin by X‐ray diffraction.
A Highly Efficient Sandwich‐Like Symmetrical Dual‐Phase Oxygen‐Transporting Membrane Reactor for Hydrogen Production by Water Splitting
Authors: Fang Wei , Steinbach Frank , Cao Zhongwei , Zhu Xuefeng , Feldhoff Armin 
Published: May 2016

AbstractWater splitting coupled with partial oxidation of methane (POM) using an oxygen‐transporting membrane (OTM) would be a potentially ideal way to produce high‐purity hydrogen as well as syngas. Over the past decades, substantial efforts have been devoted to the development of supported membranes with appropriate configurations to achieve considerable performance improvements. Herein, we describe the design of a novel symmetrical membrane reactor with a sandwich‐like structure, whereby a largescale production (>10 mL min−1 cm−2) of hydrogen and syngas can be obtained simultaneously on opposite sides of the OTM. Furthermore, this special membrane reactor could regenerate the coke‐deactivated catalyst in situ by water steam in a single unit. These results represent an important first step in the development of membrane separation technologies for the integration of multiple chemical processes.
Improvement of mechanical characteristics of glycidyl azide polymer binder system by addition of flexible polyether
Authors: Deng Jingke , Li Guoping , Xia Min , Lan Yuanfei , Luo Yunjun 
Published: May 2016

ABSTRACTTwo kinds of flexible chain polymer, poly(ethylene oxide‐co‐tetrahydrofuran) (P(EO‐co‐THF)) and polyalkylene oxide (PAO), were chosen to improve the mechanical properties of the network of glycidyl azide polymer (GAP)–based elastomers. The mechanical properties of the GAP binder system at 25 and −40 °C can be improved effectively. The effects of P(EO‐co‐THF) and PAO on the network parameters, hydrogen bonding effect, and crystallization property were studied to determine the enhancement mechanism. Based on the results, it can be concluded that for copolyurethane elastomers prepared with PAO content less than 15 wt % and P(EO‐co‐THF), the mechanical properties were enhanced by the reduction of bulk side groups in GAP, which improved the chemical crosslinking density, hydrogen bonding effect in elastomers, and the motility of the molecular chains, while for elastomers prepared with more than 15 wt % PAO, the crystallization of the PAO segments played a major role in the improvement of mechanical properties. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43840.
Preparation of poly(methyl methacrylate‐co‐butyl methacrylate) nanoparticles and their reinforcing effect on natural rubber
Authors: Liu Jin , Tian Xiaohui , Sun Jinyu , Yuan Yizhong 
Published: May 2016

ABSTRACTPoly(methyl methacrylate‐co‐butyl methacrylate) [P(MMA‐co‐BMA)] nanoparticles were synthesized via emulsion polymerization, and incorporated into natural rubber (NR) by latex compounding. Monodispersed, core‐shell P(MMA‐co‐BMA)/casein nanoparticles (abbreviated as PMBMA‐CA) were produced with casein (CA) as surfactant. The chemical structure of P(MMA‐co‐BMA) copolymers were confirmed by 1H‐NMR and FTIR analyses. Transmission electron microscopy demonstrated the core–shell structure of PMBMA‐CA, and PMBMA‐CA homogenously distributed around NR particles, indicating the interaction between PMBMA‐CA and NR. As a result, the tensile strength and modulus of NR/PMBMA‐CA films were significantly enhanced. The tensile strength was increased by 100% with 10% copolymer addition, when the molar ratio of MMA:BMA was 8:2. In addition, scanning electron microscopy and atomic force microscopy results presented that the NR/PMBMA‐CA films exhibited smooth surfaces with low roughness, and PMBMA‐CA was compatible with NR. FTIR‐ATR analyses also suggested fewer PMBMA‐CA nanoparticles migrated out of NR. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43843.
Antibacterial polycaprolactone electrospun fiber mats prepared by soluble eggshell membrane protein–assisted adsorption of silver nanoparticles
Authors: Liu Huan‐Huan , Li Qiang , Liang Xiao , Xiong Xi , Yu Jian , Guo Zhao‐Xia 
Published: May 2016

ABSTRACTAntibacterial polycaprolactone (PCL) electrospun fiber mats were prepared by coelectrospinning PCL with soluble eggshell membrane protein (SEP) in 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP), followed by adsorption of silver nanoparticles (Ag NPs) through hydrogen‐bonding interaction between the amide groups of SEP and the carboxylic acid groups capped on the surfaces of Ag NPs. The PCL/SEP fiber mat was characterized by X‐ray photoelectron spectroscopy, indicating the presence of some SEP on the fiber surface. The adsorption of Ag NPs was confirmed by transmission electron microscopy and quantitatively characterized by thermogravimetric analysis. The pH value of the silver sol used for adsorption is very important in view of the amount and dispersion state of Ag NPs adsorbed on the fibers. The Ag NP–decorated PCL/SEP fiber mats prepared at pH 3–5 exhibit strong antibacterial activity against both gram‐negative Escherichia coli and gram‐positive Bacillus subtilis. Antibacterial PCL fiber mats were also obtained similarly with the assistance of collagen (another protein) instead of SEP, showing that protein‐assisted adsorption of Ag NPs is a versatile method to prepare antibacterial electrospun fiber mats. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43850.
Effects of poloxamer 407‐induced hyperlipidemia on hepatic multidrug resistance protein 2 (Mrp2/Abcc2) and the pharmacokinetics of mycophenolic acid in rats
Authors: Kwon Mi Hye , Yoon Ji Na , Baek Yu Jin , Kim Yu Chul , Cho Yong Yeon , Kang Hee Eun 
Published: May 2016

AbstractHepatic multidrug resistance‐associated protein 2 (Mrp2) is responsible for the majority of the biliary elimination of endogenous and exogenous substances, therefore it is important to evaluate possible functional changes in Mrp2 activity under conditions of hyperlipidemia (HL). Thus, the present study assessed the protein expression and transporting activity of hepatic Mrp2 based on the in vivo biliary excretion of phenolsulfonphthalein (PSP) as a model anionic substrate for Mrp2 in poloxamer 407‐induced hyperlipidemic rats (HL rats) and compared these values with those for control rats. The pharmacokinetics of mycophenolic acid (MPA) and mycophenolic acid‐7‐O‐glucuronide (MPAG) were evaluated after the intravenous (5 mg/kg) and oral (10 mg/kg) administration of MPA to control and HL rats. In HL rats, the protein expression of hepatic Mrp2 and its biliary transporting activity exhibited significant reductions (by 24.3% and 24.6%, respectively) in the absence of a change in bile flow rate. Unexpectedly, HL and control rats showed comparable biliary excretion rates of MPAG due to the counter effects of the reduced expression and activity of Mrp2 and a 484% increase in the free fraction of MPAG in HL rats. The estimated biliary clearance value of free MPAG in HL rats was considerably slower (by 77.1%) than that in control rats. Although significant pharmacokinetic changes in total MPA and MPAG levels were not observed in HL rats, there was a marked increase in free MPA and MPAG levels. Clinically relevant pharmacokinetic changes in subjects with HL that are related to MRP2 could not be ruled out. Copyright © 2016 John Wiley & Sons, Ltd.
The Spreading of Alternatives: Is it the Perceived Choice or Actual Choice that Changes our Preference?
Authors: Luo Jiayi , Yu Rongjun 
Published: May 2016

AbstractAfter making a difficult choice, the preference rating of a chosen alternative tends to increase, and the rating of the rejected one tends to decrease. Such a change of preference is called spreading of alternatives. It is unclear whether it is the choice itself, or the choice one believes one has made that leads to preference change. Using a facial attractiveness task, we addressed this question by setting up an experiment to measure how the actual choice and perceived choice changed the preference. In the current study, participants first rated the attractiveness of female faces, and then made a choice between two faces that they had rated the same, after which, they re‐rated the female faces. Notably, in the re‐rating session, participants were given either veridical, false, or no feedback about their prior choice. This way, we were able to measure the functions of actual choice and perceived choice in rating changes. Results showed that both actual action and perceived action exert significant influence in shaping preference. The veridical feedback enhanced the spreading of alternatives effect whereas the false feedback weakened this effect, indicating that preference can be modulated by explicit manipulation. Copyright © 2016 John Wiley & Sons, Ltd.