bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of the mixed external donors on the sequence length distribution of polypropylene
Authors: Chang Hefei , Ren Shitong , Dang Xiaofei , Zhang Liaoyun , Li Huayi , Hu Youliang 
Published: November 2012

AbstractThe effects of different mixed external donors on the crystallization behavior and sequence length distribution of polypropylene prepared by MgCl2‐supported TiCl4 Ziegler–Natta catalyst were studied through successive self‐nucleation and annealing (SSA) technique. The SSA results show that the crystallization ability and the relative contents of long isotactic sequence length gradually increase with the increase of the relative component of Donor‐1 (cyclohexylmethyldimethoxysilane, dicyclohexyl(dimethoxy)silane, and dipiperidinedimethoxysilane) in the different mixed external donors when the ratio of the mixed external donors/Ti (Si/Ti) is unchanged. The thickness distribution of lamellar also becomes broader, indicating the sequence length distribution of polypropylene gets broader. The crystallization ability and the relative contents of long isotactic sequence length of polypropylene prepared by the mixed cyclohexylmethyldimethoxysilane and n‐propyltriethoxysilane (CN) external donors are lowest. However, the effect of the mixed dicyclohexyl(dimethoxy)silane and n‐propyltriethoxysilane (HN) and the mixed dipiperidinedimethoxysilane and n‐propyltriethoxysilane (PyN) external donors on the crystallization ability and sequence length of polypropylene are more significantly. Especially, the relative content of long isotactic sequence length increases sharply from 0.2 to 27.5% in the polypropylene chain of sample prepared by the mixed PyN external donors when the proportion of Donor 1 is running up to 90%. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Enhancement of mechanical and tribological properties in ring‐opening metathesis polymerization functionalized molybdenum disulfide/polydicyclopentadiene nanocomposites
Authors: Peng Shuge , Niu Yongping , Fan Xinjie 
Published: November 2012

AbstractThis study focuses on the possibility of improving performance properties of polydicyclopentadiene (PDCPD) nanocomposites for engineering applications using nanoparticles. In this article, molybdenum disulfide/polydicyclopentadiene (MoS2/PDCPD) nanocomposites have been prepared by in situ ring‐opening metathesis polymerization using reaction injecting molding (RIM) process. To enhance the interfacial adhesion between the fillers and PDCPD matrix, the surface modified MoS2 nanoparticles hybridized with dialkyldithiophosphate (PyDDP) were successfully prepared by in situ surface grafting method. The effect of low MoS2 loadings (<3 wt %) on the mechanical and tribological behaviors of PDCPD was evaluated. The results indicated that the friction coefficient of the MoS2/PDCPD nanocomposites was obviously decreased and the wear resistance of nanocomposites was greatly improved by the addition of PyDDP‐hybridized MoS2 nanoparticles; meanwhile, the mechanical properties were also enhanced. The MoS2/PDCPD nanocomposites filled with 1 wt % PyDDP‐hybridized MoS2 exhibited the best mechanical and anti‐wear properties. The friction coefficient was shown to decrease by more than 40% compared to pure PDCPD by incorporating just 1 wt % hybridized MoS2 nanoparticles, and modest increase in modulus and strength was also observed. The reinforcing and wear‐resistant mechanisms of MoS2/PDCPD nanocomposites were investigated and discussed by scanning electron microscopy. The well interfacial compatibility between the particle/matrix interfaces played an important role for the improved mechanical and tribological properties of MoS2/PDCPD nanocomposites in very low MoS2 loadings. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Transgenic quail as a model for research in the avian nervous system: A comparative study of the auditory brainstem
Authors: Seidl Armin H. , Sanchez Jason Tait , Schecterson Leslayann , Tabor Kathryn M. , Wang Yuan , Kashima Daniel T. , Poynter Greg , Huss David , Fraser Scott E. , Lansford Rusty , Rubel Edwin W. 
Published: November 2012

AbstractResearch performed on transgenic animals has led to numerous advances in biological research. However, using traditional retroviral methods to generate transgenic avian research models has proved problematic. As a result, experiments aimed at genetic manipulations on birds have remained difficult for this popular research tool. Recently, lentiviral methods have allowed the production of transgenic birds, including a transgenic Japanese quail (Coturnix coturnix japonica) line showing neuronal specificity and stable expression of enhanced green fluorescent protein (eGFP) across generations (termed here GFP quail). To test whether the GFP quail may serve as a viable alternative to the popular chicken model system, with the additional benefit of genetic manipulation, we compared the development, organization, structure, and function of a specific neuronal circuit in chicken (Gallus gallus domesticus) with that of the GFP quail. This study focuses on a well‐defined avian brain region, the principal nuclei of the sound localization circuit in the auditory brainstem, nucleus magnocellularis (NM), and nucleus laminaris (NL). Our results demonstrate that structural and functional properties of NM and NL neurons in the GFP quail, as well as their dynamic properties in response to changes in the environment, are nearly identical to those in chickens. These similarities demonstrate that the GFP quail, as well as other transgenic quail lines, can serve as an attractive avian model system, with the advantage of being able to build on the wealth of information already available from the chicken. J. Comp. Neurol.5–23, 2013. © 2012 Wiley Periodicals, Inc.
Editorial
Authors: Remick Carolyn , Hunt James , Javid Harold 
Published: November 2012

SUMMARYScientific discovery is increasingly driven by the collection, analysis, and comprehension of digital data. Collaborations between domain scientists and computer scientists can accelerate both the investigation and applications processes. The Microsoft eScience Workshop is a recognized venue for showcasing such collaborations and serves as a forum for exchanging both domain and computational researches. This editorial provides an overview of the papers that resulted from selected research collaboration presented at the 2010 Microsoft eScience workshop. Copyright © 2012 John Wiley & Sons, Ltd.
Metal‐Free Benzodithiophene‐Containing Organic Dyes for Dye‐Sensitized Solar Cells
Authors: Longhi Elena , Bossi Alberto , Di Carlo Gabriele , Maiorana Stefano , De Angelis Filippo , Salvatori Paolo , Petrozza Annamaria , Binda Maddalena , Roiati Vittoria , Mussini Patrizia Romana , Baldoli Clara , Licandro Emanuela 
Published: November 2012

AbstractTwo new metal‐free organic dyes, CR29 and CR52, with high extinction coefficients in the visible spectral region between 400–650 nm, have been synthesized. The donor–acceptor structure of the dyes feature benzodithiophene moieties BDT1 and BDT as rigid π‐conjugated spacers, which have so far been very little studied for dye‐sensitized solar cell (DSSC) applications. DFT/TDDFT calculations have been employed to guide the design of the chromophores as well as to shed light on their electronic and optical properties. Photophysical and electrochemical characterization studies have been carried out to gather information on the charge transfer processes occurring at the dye–semiconductor interfaces. Under standard AM 1.5 conditions, DSSC sensitized with CR29 showed good conversion efficiencies: 5.14 % in the liquid electrolyte cell setup and 2.47 % in the solid‐state DSSC.
SAR analysis and bioactive potentials of freshwater and terrestrial cyanobacterial compounds: a review
Authors: Nagarajan M. , Maruthanayagam V. , Sundararaman M. 
Published: November 2012

ABSTRACTFreshwater and terrestrial cyanobacteria resemble the marine forms in producing divergent chemicals such as linear, cyclic and azole containing peptides, alkaloids, cyclophanes, terpenes, lactones, etc. These metabolites have wider biomedical potentials in targeting proteases, cancers, parasites, pathogens and other cyanobacteria and algae (allelopathy). Among the various families of non‐marine cyanobacterial peptides reported, many of them are acting as serine protease inhibitors. While the micropeptin family has a preference for chymotrypsin inhibition rather than other serine proteases, the aeruginosin family targets trypsin and thrombin. In addition, cyanobacterial compounds such as scytonemide A, lyngbyazothrins C and D and cylindrocyclophanes were found to inhibit 20S proteosome. Apart from proteases, metabolites blocking the other targets of cancer pathways may exhibit cytotoxic effect. Colon and rectum, breast, lung and prostate are the worst affecting cancers in humans and are deduced to be inhibited by both peptidic and non‐peptidic compounds. Moreover, the growth of infections causing parasites such as Plasmodium, Leishmania and Trypanosoma are well controlled by peptides: aerucyclamides A‐D, tychonamides and alkaloids: nostocarboline and calothrixins. Likewise, varieties of cyanobacterial compounds tend to inhibit serious infectious disease causing bacterial, fungal and viral agents. Interestingly, portoamides, spiroidesin, nostocyclamide and kasumigamide are the allelopathic peptides determined to suppress the growth of toxic cyanobacteria and nuisance algae. Thus cyanobacterial compounds have a broad bioactive spectrum; the analysis of SAR studies will not only assist to find out the mode of action but also reveal bioactive key components. Thereby, developing the drugs bearing these bioactive skeletons to treat various illnesses is wide open. Copyright © 2012 John Wiley & Sons, Ltd.
Facile Synthesis of Well‐Defined Telechelic Alkyne‐Terminated Polystyrene in Polar Media Using ATRP With Mixed Fe/Cu Transition Metal Catalyst
Authors: Rocha Nuno , Mendonça Patrícia V. , Mendes Joana P. , Simões Pedro N. , Popov Anatoliy V. , Guliashvili Tamaz , Serra Arménio C. , Coelho Jorge F. J. 
Published: November 2012

AbstractThe synthesis of polystyrene (PS) by atom transfer radical polymerization using the Fe(0)/CuBr2 catalytic system in dimethylformamide is reported. The effects of temperature, ligand, initiator structure, and monomer to solvent ratio on the polymerization kinetics are evaluated. PS with high molecular weight, low polydispersity, and telechelic structure are achieved and successfully used for further reinitiation or the copper(I)‐catalyzed Huisgen 1,3‐dipolar cycloaddition click reaction between alkyne‐ and azide‐terminated PS. For the first time, suitable styrene polymerization rates are achieved using this cost‐effective and environmentally attractive catalytic system. This method can be very useful in macromolecular engineering to afford PS‐based materials with well‐controlled structure.
Tensile testing of “Quenching and Partitioning” microstructures with contact‐free strain measurement
Authors: Nikolei N. , Rieger T. , Bleck W. , Schenuit E. 
Published: November 2012

AbstractDas “Quenching and Partitioning” (“Q&P”)‐Konzept hat sich als ein vielversprechender Ansatz zur Realisierung der dritten Generation der Advanced High Strength Steels etabliert. Bei diesem Konzept wird ein Gefüge aus Restaustenit in einer Matrix aus angelassenem Martensit eingestellt. Die Idee ist, dass der Martensit die Festigkeit erhöht und der Restaustenit auf Grund des TRIP‐Effekts weiterhin gute Dehnungseigenschaften gewährleistet. In dieser Arbeit werden die mechanischen Eigenschaften nach der “Quenching und Partitioning”‐Behandlung von einem Nickel und Silizium legierten TRIP‐Stahl untersucht. Es werden Wärmebehandlungen durchgeführt und die mechanischen Kennwerte in Zugversuchen mit berührungsloser Dehnungsmessung ermittelt. Um den TRIP‐Effekt nachzuweisen, werden zusätzlich Zugversuche bei einer definierten plastischen Verformung unterbrochen und der verbleibende Restaustenitanteil im Bereich der Versuchslänge magnetisch ermittelt. Zudem werden die mechanischen Eigenschaften des “Quenching und Partitioning”‐Gefüges mit einem vollständig martensitischen Referenzgefüge und Literaturdaten verglichen. Die untersuchten “Quenching und Partitioning”‐Gefüge zeigen Festigkeiten von 1300 MPa bei Bruchdehnungen in der Größenordnung von über 10 %. Im Vergleich zum Abschreckmartensit werden niedrigere Festigkeiten und höhere Dehnungen erreicht. Die magnetische Restaustenitmessung als Funktion der plastischen Dehnung weist dabei eine Beteiligung des TRIP‐Effekts nach. Vergleichbare Legierungen aus der Literatur weisen ähnliche Kombinationen von Zugfestigkeit und Bruchdehnung auf. Die vorgestellte Methodik aus Glühung und Zugversuchen mit berührungsloser Dehnungsmessung mit dem Laser‐Speckle‐Verfahren hat sich für die Untersuchung anspruchsvoller Wärmebehandlungsverfahren mit kleinen Probengeometrien bewährt.
Effect of heat treatment on microstructure and property of Fe‐Cr‐B alloy
Authors: Zhang H. , Fu H. , Jiang Y. , Yu Z. , Guo H. , Lei Y. , Zhou R. , Cen Q. 
Published: November 2012

AbstractIn this article, the effect of heat treatment in different quenching temperature on microstructure and hardness of Fe‐Cr‐B alloy was studied, by contrast with boron‐free Fe‐Cr alloy. The results indicated that microstructure of boron‐free Fe‐Cr alloy consisted of the martensite and a few (Cr, Fe)7C3 type carbide. The microstructures had no obvious change with the increase of quenching temperature, but its hardness increased from 51.5 HRC to 60.8 HRC. When boron element was added into the Fe‐Cr alloy, the netlike eutectic structure began to break and spheroidizing after quenching, in which the borocarbide turned into spherical groups and network Fe2B phase was broken. Moreover, the portion of martensite increased, and the amount of secondary carbide decreased, and the size of secondary carbide began to largen after quenching. When the quenching temperature reached 1100°C, secondary carbide particles dissolved in the matrix wholly. The hardness of Fe‐Cr‐B alloy increased with the increase of quenching temperature below 1050°C. The hardness of sample containing 2.0% B and quenching at 1050°C reached 66.7 HRC. The hardness of Fe‐Cr‐B alloy had no obvious change when quenching temperature continued to increase. After tempered at 200°C, the microstructure of Fe‐Cr‐B alloy had no significant change and its hardness had slight decrease. The hardness of sample containing 2.0% B tempered at 200°C reached 63.9 HRC.
Modeling the shape of flat deposits during spray forming using a scanning gas atomizer
Authors: Cui C. , Schulz A. , Uhlenwinkel V. 
Published: November 2012

AbstractA three‐dimensional shape model, tracing the coordinates of the moving surface of a growing flat deposit spray‐formed using a scanning gas atomizer, has been developed in this study. Mass flux distributions in the spray cones generated by the scanning atomizer under a typical spray forming condition have been revealed for the shape modeling. Geometrical evolution of flat deposits in spray forming has been investigated based on analysis of the scanning mechanism of the atomizer. The influence of processing conditions on the shape and dimensions of flat deposits have been simulated and discussed. Finally, the shape modeling has been validated by experimental investigations.
A Unified Framework for the Prioritization of Organ Transplant Patients: Analytic Hierarchy Process, Sensitivity and Multifactor Robustness Study
Authors: Lin Carol S. , Harris Shannon L. 
Published: November 2012

ABSTRACTFair and equitable allocation of donor organs in the USA is a daunting yet necessary task, which can mean the difference between life and death for patients on transplant waiting lists. This paper proposes a multi‐criterion decision‐making model using the analytic hierarchy process to allow for an allocation decision to be made on the basis of urgency, efficiency, benefit and equity. These four perspectives and objectives can be broken down into both quantitative and qualitative measures, which can be easily combined and weighted through group consensus. The proposed model overcomes the limitations of a single type of system, integrates the views of many organ allocation philosophies, improves the decision maker's ability to collaborate, helps justify the decision and reaches the optimal result. In addition, the proposed profile matrix allows decision makers to graphically trade off criteria against each other and to clearly articulate the decision rationale. Our computational study suggests that the proposed model not only satisfactorily serves the objectives of many constituents, but also remains noticeably robust under various criteria‐weight‐change scenarios. It improves stakeholder confidence in the organ allocation procedure, maximizes the usefulness of the organ and enhances welfare to society. Copyright © 2012 John Wiley & Sons, Ltd.
Early radial digital neuropathy of the thumb due to flexor pollicis longus tendinitis: Value of ultrasound in an uncommon mild neuropathy
Authors: Yalcin Elif , Akyuz Mufit , Onder Burcu 
Published: November 2012

ABSTRACTIntroductionA 50‐year‐old man developed intermittent paresthesia of the outer portion of the right thumb. Paresthesia increased with thumb abduction and flexion. The remainder of the physical examination was normal.MethodsRoutine motor and sensory examinations of the median and ulnar nerves were within normal ranges.ResultsUltrasonographic studies revealed that a tenosynovitis of the flexor pollicis longus of the right thumb was compressing the radial digital nerve of the thumb.ConclusionsUltrasonographic evaluation was used in conjunction with nerve conduction studies to diagnose digital neuropathy. Ultrasound is a beneficial, complementary tool to electrodiagnostic studies, especially for uncommon focal neuropathies. Muscle Nerve 47: 772–775, 2013
Phenolic Profiling of Portuguese Propolis by LC–MS Spectrometry: Uncommon Propolis Rich in Flavonoid Glycosides
Authors: Falcão Soraia I. , Vale Nuno , Gomes Paula , Domingues Maria R. M. , Freire Cristina , Cardoso Susana M. , Vilas‐Boas Miguel 
Published: November 2012

ABSTRACTIntroductionPropolis is a chemically complex resinous substance collected by honeybees (Apis mellifera) from tree buds, comprising plant exudates, secreted substances from bee metabolism, pollen and waxes. Its chemical composition depends strongly on the plant sources available around the beehive, which have a direct impact in the quality and bioactivity of the propolis. Being as Portugal is a country of botanical diversity, the phenolic characterisation of propolis from the different regions is a priority.ObjectiveExtensive characterisation of the phenolic composition of Portuguese propolis from different continental regions and islands.MethodForty propolis ethanolic extracts were analysed extensively by liquid chromatography with diode‐array detection coupled to electrospray ionisation tandem mass spectrometry (LC–DAD–ESI–MSn).ResultsSeventy‐six polyphenols were detected in the samples and two groups of propolis were established: the common temperate propolis, which contained the typical poplar phenolic compounds such as flavonoids and their methylated/esterified forms, phenylpropanoid acids and their esters, and an uncommon propolis type with an unusual composition in quercetin and kaempferol glycosides – some of them never described in propolis.ConclusionThe method allowed the establishment of the phenolic profile of Portuguese propolis from different geographical locations, and the possibility to use some phenolic compounds, such as kaempferol‐dimethylether, as geographical markers. Data suggest that other botanical species in addition to poplar trees can be important sources of resins for Portuguese propolis. Copyright © 2012 John Wiley & Sons, Ltd.
A Colourful University Life? Transnational Higher Education and the Spatial Dimensions of Institutional Social Capital in Hong Kong
Authors: Waters Johanna , Leung Maggi 
Published: November 2012

ABSTRACTTransnational higher education represents a lesser‐known aspect of the international education industry. In relation to the UK, transnational education is a booming business. British qualifications are offered in 217 countries outside the UK, representing in excess of 388,000 students in total. These students are fascinating precisely because they are acquiring an ‘international education’ in situ, raising a number of pertinent questions relating to the ‘capital’ young people are developing. How valuable is a British degree delivered entirely overseas? What does it actually represent – both conceptually, in terms of students' (im)mobilities, and in relation to individuals' embodied experiences of transnational higher education? This paper draws on the findings of a qualitative project examining British degree programmes offered in Hong Kong and their implications for young people locally. We focus on the experiences of students and graduates and the intentions of a number of UK ‘providers’ (representing different British higher education institutions). We explore the social capital accessible to students undertaking transnational educational programmes and focus in particular upon the spatial availability of ‘institutional social capital’. We argue that the ability of young people to cultivate social capital in the context of transnational higher education is circumscribed in various ways, with implications for subsequent employment opportunities and social mobility. Our paper furthermore responds to recent calls to spatialise the conversion of social capital. Copyright © 2012 John Wiley & Sons, Ltd.
Atomic scale modeling of edge a‐type dislocations in InN
Authors: Kioseoglou Joseph 
Published: November 2012

AbstractThe atomic geometry and electronic structure of a‐edge threading dislocations (TDs) in InN are investigated by combined interatomic potential and ab initio calculations. Initially isolated dislocation cores are included in supercells of ∼30 000 atoms and relaxed by Tersoff potentials and the III‐species environment approach. The relaxed core structures are then extracted in the form of cluster‐hybrids and total energy as well as electronic structure calculations are performed under both the generalized gradient approximation (GGA) and the local density approximation implementing modified pseudopotentials (MPP‐LDA). Interatomic potentials identify the 5/7‐atom core as the most energetically stable while ab initio calculations under both implemented approaches point to the 8‐atom ring as most energetically stable. In the present contribution, results of density functional theory (DFT) calculations on a novel dislocation core model comprising a 10‐atom ring are presented and compared to those of commonly considered cores. It is found that all considered dislocation cores modify the band structure of InN in a distinct manner due to their distinct structural features. Especially the 4‐ and 5/7‐atom cores are identified as sources of higher electron concentrations in InN, enhancing its n‐type conductivity.