bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pt‐IrO2nanorod array electrode for oxygen evolution in PEM water electrolysis cell
Authors: Ye Feng , Hu Weiwei , Liu Hui , Liu Jiangshan , Li Jianling , Wang Xindong , Yang Jun 
Published: August 2012

ABSTRACTPt‐IrO2nanorod arrays supported on the carbon paper were fabricated directly using the dip‐coating/calcination method. The nanorod arrays and ordering were characterized by scanning electron microscope. Pt‐IrO2/carbon paper directly used as catalyst layer and support layer with the united structure on the anode side is demonstrated to have excellent electrocatalytic activity for oxygen evolution in proton exchange membrane (PEM) water electrolysis cell. By employing the Pt‐IrO2(Pt:Ir = 3:7) at anode and commercial 20% Pt/C catalysts at cathode, a cell voltage as low as 1.86 V was achieved under high current density with the total noble metal loading of 0.8 mg cm−2. The Pt‐IrO2electrocatalysts with uniform nanorod arrays structure, good conductivity are supposed to play a key role for their enhanced catalytic activity toward oxygen evolution reaction. The study in this work might open an opportunity for the efficient utilization of valuable catalytic materials in PEM water electrolysis by decreasing the catalyst loading and provide a facile route to fabricate electrode based on direct calcination of noble metal and metal oxide nanoparticles onto carbon paper. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Properties of melt processable PTFE/PEEK blends: The effect of reactive compatibilization using electron beam irradiated melt processable PTFE
Authors: Frick Achim , Sich Dorota , Heinrich Gert , Lehmann D. , Gohs U. , Stern Claudia 
Published: August 2012

AbstractFor the first time, blends of melt processable polytetrafluoroethylene (MP PTFE) with polyetheretherketone (PEEK) in the MP PTFE/PEEK ratio of 100/0, 80/20, 50/50, 20/80, and 0/100 w/w were prepared and characterized. MP PTFE/PEEK blends are attractive materials due to the combination of low coefficient of friction and universal chemical resistance of MP PTFE with good wear resistance and mechanical strength of PEEK while maintaining high thermal stability of both. Miscibility, phase morphology, and mechanical properties of the new MP PTFE/PEEK blends were investigated. To improve their end‐use properties, an attempt of reactive compounding with the electron beam irradiated MP PTFE (e‐beam MP PTFE) was made. The reactive compounding was done in two steps, that is, the preparation of a masterbatch (MB) consisting of e‐beam MP PTFE/PEEK (50/50 w/w) and subsequent melt blending of MP PTFE/PEEK with varying concentrations of MB. The e‐beam irradiation of MP PTFE carried out in air atmosphere and at room temperature with a dose of 50 kGy results in its chain scission associated with formation of COF and COOH functional groups. Such modified MP PTFE can be used to compatibilize MP PTFE/PEEK blends. Reactive compatibilized blends exhibit improved phase morphology and mechanical properties. Especially for MP PTFE/PEEK 50/50 blends, a great improvement of almost 250% in strain at break, 40% in stress at break, and more than 600% in toughness was achieved. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Study on thermal and biodegradation resistance of tropical wood material composites
Authors: Hamdan Sinin , Islam Md. Saiful , Ahmed Abu Saleh , Rahman Md. Rezaur , Rusop Mohamad 
Published: August 2012

AbstractThermal stability and decay resistance properties of tropical wood polymer composites (WPCs) were investigated in this study. WPCs were prepared from several selected tropical wood species by impregnating the woods with methyl methacrylate (MMA) which was combined with a crosslinker, hexamethylene diisocyanate (HMDIC). The impregnation of wood with the monomer systems and polymerization were accomplished by vacuum‐pressure method. Thermal properties of manufactured WPC in terms of thermogravimetric analysis and differential scanning calorimetry were evaluated, and an improvement in thermal stability was found for fabricated WPC. The wood was then exposed to two types of fungi; white‐rot (polyporous versicolor) and brown‐rot (postia placenta), for 12 weeks. Decay was assessed through percentage (%) of weight loss. A significant improvement was found in the treated woods compared to the untreated ones. The improvement in properties was observed as more potential with the MMA/HMDIC combination. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Crystallization behavior of polybutadiene containing silica particles
Authors: Doan Vu Anh , Nobukawa Shogo , Ohtsubo Shigeki , Tada Toshio , Yamaguchi Masayuki 
Published: August 2012

AbstractThe effect of silica particles (silica), which are petroleum‐free products, on the isothermal and nonisothermal crystallizations of cis‐1,4‐poly(butadiene) rubber (BR) is investigated. DSC measurements reveal that silica accelerates the crystallization of BR. As a result, BR‐containing silica shows crystallization even after crosslinking reaction. Because of the enhanced crystallization, the tensile modulus is much higher than that without silica in the range between the glass transition temperature and the melting point. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Overview of loggerhead turtles coastal nets interactions in the Mediterranean Sea
Authors: Echwikhi Khaled , Jribi Imed , Bradai Mohamed Nejmeddine , Bouain Abderrahmen 
Published: August 2012

ABSTRACT

In the Mediterranean Sea, trawl nets and drifting longlines have been recognized as methods that capture thousands or tens of thousands of turtles. However, the possible impact of other fishing methods has not been adequately addressed, especially for artisanal and amateur fisheries that use coastal nets.
Coastal net fisheries, including driftnets and set nets, used at a much shallower depth (<40 m) in the Mediterranean, result in a large bycatch of loggerhead turtles in the neritic zone. The mortality rate with these fisheries seems to be higher than with other commercial fisheries.
In the Mediterranean context, additional assessments on fishery characteristics and fishing gear parameters to: (i) develop a simple and unanimous definition of an artisanal fishery; and (ii) standardize units for reporting sea turtle bycatch with coastal nets, are needed to provide an understanding of the current relative degree of risk coastal net fisheries pose to turtle populations.
Mitigation measures based on (a) gear‐technology approaches, (b) fisheries closures, and (c) increased awareness and education of fishermen, must be considered as priorities and should be implemented without further delay. Copyright © 2012 John Wiley & Sons, Ltd.
Heterochronic Protein Expression Patterns in the Developing Embryonic Chick Cerebellum
Authors: Gilbert Ea , Lim Yh , Vickaryous Mk , Armstrong CL 
Published: August 2012

AbstractThe advantages of the embryonic chick as a model for studying neural development range from the relatively low cost of fertilized eggs to the rapid rate of development. We investigatedin ovocerebellar development in the chick, which has a nearly identical embryonic period as the mouse (19–22 days). We focused on three antigens: Calbindin (CB), Zebrin II (ZII), and Calretinin (CR), and our results demonstrate asynchronous expression patterns during cerebellar development. Presumptive CB+ Purkinje cells are first observed at embryonic day (E)10 in clusters in posterior cerebellum. At E12, corresponding with global expression of CB across the cerebellum, Purkinje cells began to express ZII. By E14–E16, Purkinje cells disperse into a monolayer and develop a pattern of alternating immunopositive and immunonegative ZII stripes. CR is initially expressed by clusters of presumptive Purkinje cells in the nodular zone at E8. However, this expression is transient and at later stages, CR is largely confined to the granule and molecular layers. Before hatch (E18–E20), Purkinje cells adopt a morphologically mature phenotype with complex dendritic arborizations. Comparing this data to that seen in mice, we found that the sequence of Purkinje cell formation, protein expression, and development is similar in both species, but these events consistently begin ∼5–7 days earlier in the precocial chick cerebellum, suggesting an important role for heterochrony in neurodevelopment. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
Ölpflanzen in Europa
Authors: Bickel Susanne 
Published: August 2012

AbstractNachwachsende Rohstoffe erhalten zunehmende Bedeutung in Industrie und Technik. Ölpflanzen liefern Pflanzenöle, die für unsere Ernährung wichtig sind und gleichzeitig als Industrierohstoff eingesetzt werden können. Sie werden mittlerweile nicht nur als Treibstoff verwendet, sondern auch zur Herstellung von Schmierstoffen, Hydraulikölen, Waschmitteln, Farben und Lacken und zahlreichen weiteren Produkten. In Europa ist Raps die vorherrschende Ölpflanze, gefolgt von der Sonnenblume und der Olive. Rapsöl wird für die Säuglingsernährung empfohlen, weil es eine hohe Konzentration an α‐Linolensäure enthält, die einen wichtigen Baustein für die Gehirnentwicklung liefert.
Coregonen: Umkehrung der Artbildung
Authors: Kronberg Inge 
Published: August 2012

AbstractArten entstehen und vergehen – dieser Wandel der Diversität lässt sich nicht nur in erdgeschichtlichen Maßstäben beobachten. Diversitätsverluste durch den Einfluss des Menschen zeigen sich bereits innerhalb weniger Jahrzehnte. Arten verschwinden nicht nur, weil ihre Dichte schrittweise zurückgeht, sondern auch, weil sie sich mit nahe verwandten Arten vermischen. Das gilt besonders, wenn ein Lebensraum beispielsweise durch Eutrophierung so eintönig wird, dass Möglichkeiten zur spezifischen Einnischung schließlich fehlen.
Die Herstellung von Agarplatten für mikrobiologische Versuche
Authors: Schrödel Andrea 
Published: August 2012

AbstractBakterienkulturen können auf verschiedene Art und Weise gezüchtet werden. Setzt man dem flüssigen Nährmedium ein Geliermittel zu und gießt dieses noch heiß in Petrischalen, so erhält man nach dem Abkühlen Platten mit festem Nährboden von gelatineähnlicher Konsistenz. Auf diesen können Bakteriensuspensionen ausplattiert und bebrütet werden, bis einzelne Kolonien zu sehen sind.
Bernhard Rensch – biologischer Universalist im 20. Jahrhundert
Authors: Hoßfeld Uwe , Levit Georgy S. , Simunek Michal 
Published: August 2012

AbstractBernhard Rensch war ein ausgesprochen vielseitiger Biologe. Er gilt nicht nur im deutschen Sprachraum als einer der bedeutendsten (Evolutions‐)Biologen des 20. Jahrhunderts. Seine wissenschaftlichen Interessengebiete umfassten die Art‐ und Rassenbildung, Zoogeografie, Tierökologie, Tierpsychologie und die Synthetische Theorie der Evolution bis hin zur Biophilosophie und Kunst.
Lys53 of Ribosomal Protein L36AL and the CCA End of a tRNA at the P/E Hybrid Site Are in Close Proximity on the Human Ribosome
Authors: Hountondji Codjo , Bulygin Konstantin , Woisard Anne , Tuffery Pierre , Créchet Jean‐Bernard , Pech Markus , Nierhaus Knud H. , Karpova Galina , Baouz Soria 
Published: August 2012

AbstractPreviously we have shown that the CCA end of a P‐tRNA can be crosslinked with the RPL36AL protein of the large subunit of mammalian ribosomes; it belongs to the L44e protein family present in all eukaryotic and archaeal ribosomes. Here we confirm and extend this finding and demonstrate that: 1) this crosslink is specific for a tRNA at the P/E hybrid site, as a tRNA in all other tRNA positions of pre‐translocational ribosomes could not be crosslinked with a ribosomal protein, 2) the crosslink was formed most efficiently with C74 and C75 of P/E‐tRNA, but could also connect the ultimate A of this tRNA with Lys53 of protein RPL36AL, 3) this protein contains seven monomethylated residues (three lysyl and three arginyl residues, as well as glutaminyl residue 51), 4) Q51 is part of a conserved GGQ motif in the L44e proteins in eukaryotic 80S ribosomes that is identical to the universally conserved motif of release factors implicated in promoting peptidyl‐tRNA hydrolysis, and 5) the large number of modifications, in which some of the residues were methylated to about 50 %, might indicate that protein RPL36AL is a preferential target for regulation.
A Raman Spectroscopic Study of the Speciation of Vanadia Supported on Ceria Nanocrystals with Defined Surface Planes
Authors: Wu Zili , Li Meijun , Overbury Steven H. 
Published: August 2012

AbstractVanadia (VOx) supported on ceria (CeO2) nanocrystals with defined surface planes, which includes rods, cubes and octahedra, was synthesized and used to explore the effect of support surface structure on the speciation of surface vanadia. The vanadia structures on these ceria “nanoshapes” were identified by in situ visible and UV Raman spectroscopy as a function of loading and calcination temperature, and they include monomeric, dimeric, trimeric, polymeric vanadia, and eventually crystalline V2O5 and CeVO4 as vanadia loading increases. As expected, the faceted ceria nanocrystals provide a rather homogeneous platform for anchoring the vanadia. At low vanadia surface density, only monomeric vanadia exists on the ceria nanoshapes, in contrast to vanadia supported on polycrystalline CeO2 in which multiple vanadia species coexist. Formation of CeVO4 from the reaction between surface vanadia and ceria upon high temperature calcination was compared for the three ceria nanoshapes with similar surface vanadia density (≈1/4 monolayer). It was found that both the surface structure and the amount of defect sites on the ceria nanoshapes play major roles in the production of CeVO4. The easier formation of CeVO4 on ceria rods, compared with cubes or octahedra, is attributed to the rods’ lowest surface oxygen vacancy formation energy and largest amount of defect sites.
Aromaticity‐Controlled Thermal Stability of Photochromic Systems Based on a Six‐Membered Ring as Ethene Bridges: Photochemical and Kinetic Studies
Authors: Yang Yuheng , Xie Yongshu , Zhang Qiong , Nakatani Keitaro , Tian He , Zhu Weihong 
Published: August 2012

AbstractThree photochromic compounds—2‐butyl‐5,6‐bis[5‐(4‐methoxyphenyl)‐2‐methylthiophen‐3‐yl]‐1 H‐benzo[de]isoquinoline‐1,3(2 H)‐dione (BTE‐NA), 4,5‐bis[5‐(4‐methoxyphenyl)‐2‐methylthiophen‐3‐yl]benzo[c][1,2,5]thiadiazole (BTA), and BTTA, which contain naphthalimide, benzothiadiazole, and benzobisthiadiazole as six‐membered ethene bridges with different aromaticities—were systematically studied in solution, sol–gel, and single‐crystal states. They exhibit typical photochromic performance with considerably high cyclization quantum yields. BTE‐NA, BTA, and BTTA form a typical donor–π–acceptor (D–π–A) system with significant intramolecular charge transfer (ICT) between HOMO and LUMO upon excitation, thus realizing the fluorescence modulation by both photochromism and solvatochromism. The three ethene bridges with different degrees of aromaticity can provide a systematic comparison of the thermal stability evolution for their corresponding closed forms (c‐BTE‐NA, c‐BTA, and c‐BTTA). c‐BTE‐NA shows first‐order decay in various solvents from cyclohexane to acetonitrile. c‐BTA only shows first‐order decay in polar solvents such as chloroform, whereas it is stable in nonpolar solvents like toluene. In contrast, the less aromatic property of BTTA gives rise to its unprecedented thermal stability in various solvents even at elevated temperatures in toluene (328 K). Moreover, the small energy barrier between the parallel and antiparallel conformers allows the full conversion from BTTA to c‐BTTA. In well‐ordered crystal states, all three compounds adopt a parallel conformation. Interestingly, BTTA forms a twin crystal of asymmetric nature with interactions between the electron‐rich oxygen atom of the methoxy group and the carbon atom of the electron‐deficient benzobisthiadiazole moiety. This work contributes to the understanding of aromaticity‐controlled thermal stability of photochromic systems based on a six‐membered ring as an ethene bridge, and a broadening of the novel building blocks for photochromic bisthienylethene systems.
New Multifunctional Porous Materials Based on Inorganic–Organic Hybrid Single‐Walled Carbon Nanotubes: Gas Storage and High‐Sensitive Detection of Pesticides
Authors: Wang Feng , Zhao Jinbo , Gong Jingming , Wen Lili , Zhou Li , Li Dongfeng 
Published: August 2012

AbstractSingle‐walled carbon nanotubes (SWNTs) that are covalently functionalized with benzoic acid (SWNT‐PhCOOH) can be integrated with transition‐metal ions to form 3D porous inorganic–organic hybrid frameworks (SWNT‐Zn). In particular, N2‐adsorption analysis shows that the BET surface area increases notably from 645.3 to 1209.9 m2 g−1 for SWNTs and SWNT‐Zn, respectively. This remarkable enhancement in the surface area of SWNT‐Zn is presumably due to the microporous motifs from benzoates coordinated to intercalated zinc ions between the functionalized SWNTs; this assignment was also corroborated by NLDFT pore‐size distributions. In addition, the excess‐H2‐uptake maximum of SWNT‐Zn reaches about 3.1 wt. % (12 bar, 77 K), which is almost three times that of the original SWNTs (1.2 wt. % at 12 bar, 77 K). Owing to its inherent conductivity and pore structure, as well as good dispersibility, SWNT‐Zn is an effective candidate as a sensitive electrochemical stripping voltammetric sensor for organophosphate pesticides (OPs): By using solid‐phase extraction (SPE) with SWNT‐Zn‐modified glassy carbon electrode, the detection limit of methyl parathion (MP) is 2.3 ng mL−1.
Local Coordination Geometry and Spin State in Novel FeII Complexes with 2,6‐Bis(pyrazol‐3‐yl)pyridine‐Type Ligands as Controlled by Packing Forces: Structural Correlations
Authors: Craig Gavin A. , Costa José Sánchez , Roubeau Olivier , Teat Simon J. , Aromí Guillem 
Published: August 2012

AbstractA substituted 2,6‐bis(pyrazol‐3‐yl)pyridine (3‐bpp) ligand, H4L, created to facilitate intermolecular interactions in the solid, has been used to obtain four novel FeII complexes: [Fe(H4L)2](ClO4)2⋅2 CH3NO2⋅2 H2O, [Fe(H4L)(H2LBF2)](BF4)⋅5 C3H6O (H2LBF2 is an in situ modified version of H4L), [Fe(H4L)2](ClO4)2⋅2 C3H7OH and [Fe(H4L)2](ClO4)2⋅4 C2H5OH. Changing of spin‐inactive components (solvents, anions or distant ligand substituents) causes differences to the coordination geometry of the metal that are key to the magnetic proper‐ ties. Magnetic measurements show that, contrary to the previously published complex [Fe(H4L)2](ClO4)2⋅H2O⋅2 CH3COCH3, the newly synthesised compounds remain in the high‐spin (HS) state at all temperatures (5–300 K). A member of the known family of FeII/3‐bpp complexes, [Fe(3‐bpp)2](ClO4)2⋅1.75 CH3COCH3⋅1.5 Et2O, has also been prepared and characterised structurally. In the bulk, this compound exhibits a gradual and incomplete spin transition near 205 K. The single‐crystal structure is consistent with it being HS at 250 K and partially low spin at 90 K. Structural analysis of all these compounds reveals that the exact configuration of intermolecular interactions affects dramatically the local geometry at the metal, which ultimately has a strong influence on the magnetic properties. Along this line, the geometry of FeII in all published 3‐bpp compounds of known structure has been examined, both by calculating various distortion indices (Σ, Θ, θ and Φ) and by continuous shape measures (CShMs). The results reveal correlations between some of these parameters and indicate that the distortions from octahedral geometry observed on HS systems are mainly due to strains arising from intermolecular interactions. As previously suggested with other related compounds, we observe here that strongly HS‐distorted systems have a larger tendency to remain in that state.
Hydrogen Bonding Directed Supramolecular Polymerisation of Oligo(Phenylene‐Ethynylene)s: Cooperative Mechanism, Core Symmetry Effect and Chiral Amplification
Authors: Wang Feng , Gillissen Martijn A. J. , Stals Patrick J. M. , Palmans Anja R. A. , Meijer E. W. 
Published: August 2012

AbstractThe design of supramolecular motifs with tuneable stability and adjustable supramolecular polymerisation mechanisms is of crucial importance to precisely control the properties of supramolecular assemblies. This report focuses on constructing π‐conjugated oligo(phenylene ethynylene) (OPE)‐based one‐dimensional helical supramolecular polymers that show a cooperative growth mechanism. Thus, a novel set of discotic molecules comprising a rigid OPE core, three amide groups, and peripheral solubilising wedge groups featuring C3 and C2 core symmetry was designed and synthesised. All of the discotic molecules are crystalline compounds and lack a columnar mesophase in the solid state. In dilute methylcyclohexane solution, one‐dimensional supramolecular polymers are formed stabilised by threefold intermolecular hydrogen bonding and π–π interactions, as evidenced by 1H NMR measurements. Small‐angle X‐ray and light scattering measurements reveal significant size differences between the columnar aggregates of C3‐ and C2‐symmetrical discotics, that is, the core symmetry strongly influences the nature of the supramolecular polymerisation process. Temperature‐dependent CD measurements show a highly cooperative polymerisation process for the C3‐symmetrical discotics. In contrast, the self‐assembly of C2‐symmetrical discotics shows a smaller enthalpy release upon aggregation and decreased cooperativity. In all cases, the peripheral stereogenic centres induce a preferred handedness in the columnar helical aggregates. Moreover, one stereogenic centre suffices to fully bias the helicity in the C2‐symmetrical discotics. Finally, chiral amplification studies with the C3‐symmetrical discotics were performed by mixing chiral and achiral discotics (sergeants‐and‐soldiers experiment) and discotics of opposite chirality (majority‐rules experiment). The results demonstrate a very strong sergeants‐and‐soldiers effect and a rather weak majority‐rules effect.
Donor‐π‐Acceptors Containing the 10‐(1,3‐Dithiol‐2‐ylidene)anthracene Unit for Dye‐Sensitized Solar Cells
Authors: Bouit Pierre‐Antoine , Marszalek Magdalena , Humphry‐Baker Robin , Viruela Rafael , Ortí Enrique , Zakeeruddin Shaik M. , Grätzel Michael , Delgado Juan Luis , Martín Nazario 
Published: August 2012

AbstractTwo donor–acceptor molecular tweezers incorporating the 10‐(1,3‐dithiol‐2‐ylidene)anthracene unit as donor group and two cyanoacrylic units as accepting/anchoring groups are reported as metal‐free sensitizers for dye‐sensitized solar cells. By changing the phenyl spacer with 3,4‐ethylenedioxythiophene (EDOT) units, the absorption spectrum of the sensitizer is red‐shifted with a corresponding increase in the molar absorptivity. Density functional calculations confirmed the intramolecular charge‐transfer nature of the lowest‐energy absorption bands. The new dyes are highly distorted from planarity and are bound to the TiO2 surface through the two anchoring groups in a unidentate binding form. A power‐conversion efficiency of 3.7 % was obtained with a volatile CH3CN‐based electrolyte, under air mass 1.5 global sunlight. Photovoltage decay transients and ATR‐FTIR measurements allowed us to understand the photovoltaic performance, as well as the surface binding, of these new sensitizers.
ChemInform Abstract: Metallic Properties of Ba2Cu3P4 and BaCu2Pn2 (Pn: As, Sb).
Authors: Saparov Bayrammurad , Sefat Athena S. 
Published: August 2012

AbstractNeedle‐shaped crystals of Ba2Cu3P4 and plate‐like crystals of BaCu2As2 and α‐BaCu2Sb2, a new polymorph of BaCu2Sb2, are prepared from the elements in a molten Sn or Pb flux (950 °C, 20—24 h).
ChemInform Abstract: K2NaOsO5.5 and K3NaOs2O9: The First Osmium Perovskites Containing Alkali Cations at the “A” Site.
Authors: Mogare Kailash M. , Klein Wilhelm , Jansen Martin 
Published: August 2012

AbstractK2NaOsO5.5 (I) and K3NaOs2O9 (II) are synthesized by solid state reaction of mixtures of KO2, Na2O2, and Os powder in the ratio 2:0.5:1 and 2:1:2, resp.