bluuebunny/crossref_metadata_2025_split huggingface dataset:
Iodine diffusion during iodine‐vapor curing and its effects on the morphology of polycarbosilane/silicon carbide fibers
Authors: Hong Junsung , Cho Kwang‐Youn , Shin Dong‐Geun , Kim Jung‐Il , Riu Doh‐Hyung 
Published: July 2015

ABSTRACTIodine‐vapor curing is used to produce continuous SiC fibers from polycarbosilane (PCS), but attempts to limit the uptake of oxygen during the curing process result in SiC fibers with different morphologies and pore types. The cause of this distinct transformation in the morphology of the fibers is determined in this study by tracing the distribution of iodine in PCS fibers cured either at a set temperature or for a given period. The results reveal that the final morphology of the fibers is dependent on the degree of iodine diffusion, or on the extent of their cross‐linked area. Using this knowledge, fibers with three distinct morphologies are produced by controlling the curing conditions. Optimization of this curing process is shown to inhibit the formation of pores and retard the incorporation of oxygen, while still allowing the fibers to retain their cylindrical shape. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42687.
Simultaneous quantitation of acetylsalicylic acid and clopidogrel along with their metabolites in human plasma using liquid chromatography tandem mass spectrometry
Authors: Chhonker Yashpal S. , Pandey Chandra P. , Chandasana Hardik , Laxman Tulsankar Sachin , Prasad Yarra Durga , Narain V. S. , Dikshit Madhu , Bhatta Rabi S. 
Published: July 2015

AbstractThe interest in therapeutic drug monitoring has increased over the last few years. Inter‐ and intra‐patient variability in pharmacokinetics, plasma concentration related toxicity and success of therapy have stressed the need of frequent therapeutic drug monitoring of the drugs. A sensitive, selective and rapid liquid chromatography coupled with tandem mass spectrometry (LC‐MS/MS) method was developed for the simultaneous quantification of acetylsalicylic acid (aspirin), salicylic acid, clopidogrel and carboxylic acid metabolite of clopidogrel in human plasma. The chromatographic separations were achieved on Waters Symmetry ShieldTM C18 column (150 × 4.6 mm, 5 µm) using 3.5 mm ammonium acetate (pH 3.5)–acetonitrile (10:90, v/v) as mobile phase at a flow rate of 0.75 mL/min. The present method was successfully applied for therapeutic drug monitoring of aspirin and clopidogrel in 67 patients with coronary artery disease. Copyright © 2015 John Wiley & Sons, Ltd.
An Empirical Study of Phosphine Ligands for the Methoxycarbonylation of Medium‐Chain Alkenes
Authors: Holzapfel Cedric , Bredenkamp Tyler 
Published: July 2015

AbstractThe methoxycarbonylation reaction provides a route to the synthesis of esters from medium‐chain alkenes that may be used as fuel supplements. However, the known productive catalytic systems are expensive and/or unstable at elevated temperatures. Most of the data available on the methoxycarbonylation of alkenes is derived from ethylene and styrene as substrates. To broaden the scope, we conducted a comparative study of a range of phosphine ligands under comparable conditions for the methoxycarbonylation of 1‐octene. The results demonstrate that a number of ligand structural motifs facilitate the process effectually. Furthermore, the critical importance of alkene isomerization and the acid/ligand and Pd/ligand ratios are presented.
Digital Image Processing Technique to Investigate the Hydrodynamics of an Airlift Reactor with Double Downcomer
Authors: Behin Jamshid , Farhadian Negin 
Published: July 2015

AbstractDigital image processing, an innovative cost‐effective technique, was employed to investigate the hydrodynamics of a rectangular internal loop airlift reactor with double downcomer. The whole reactor was divided into two downcomers and a riser by means of two vertical blades to achieve a new geometry. Air and water served as gas and liquid media. Experimental measurements were performed by visualizing the concentration of a colored tracer by a digital camera. The captured successive images at specified time intervals were analyzed by the ImageJ software to turn images into quantifiable data. For four reactor geometries, the residence time distribution curves in individual sections and the liquid mixing performance were determined by this noninvasive method. The speed of this technique to capture real‐time data of flow patterns may be one of the most important concerns for imaging multiphase flows in process industries.
Homogenous Core–Shell Nitrogen‐Doped Carbon Nanotubes for the Oxygen Reduction Reaction
Authors: Liu Jiehua , Shen Anli , Wei Xiangfeng , Wang Shuangyin , Zhou Kuan , Xu Jiaqi 
Published: July 2015

AbstractNanoarchitectures provide a new impulse to develop highly efficient electrocatalysts for the oxygen reduction reaction (ORR). Nitrogen‐doped 1D or 2D carbon‐based catalysts exhibit highly catalytic performances, owing to their distinctive features. Of great interest is the fabrication of novel nanostructures combining the advantages of 1D and 2D materials. To achieve this challenge, homogenous core–shell nitrogen‐doped carbon nanotubes were successfully prepared by using a simple one‐pot method. The unique structure possesses the features of common carbon nanotubes (core) and standing graphite (shell). The novel structure with a synergistic effect of 1D and 2D materials contributes to enhanced ORR activity. Moreover, the core–shell catalysts exhibit long‐term stability and high tolerance to methanol‐poisoning effects, which are shortfalls for commercial Pt/C electrocatalysts.
Corrosion Prevention Mechanism of Aluminum Metal in Superconcentrated Electrolytes
Authors: Yamada Yuki , Chiang Ching Hua , Sodeyama Keitaro , Wang Jianhui , Tateyama Yoshitaka , Yamada Atsuo 
Published: July 2015

AbstractMetal corrosion is a serious problem that has beset various electrochemical systems. For lithium‐ion batteries, oxidative corrosion of an Al current collector has been a great challenge in designing new electrolyte materials, and only a few lithium salts (e.g. LiPF6) are in practical use. The present work shows effective suppression of Al corrosion up to 4.5 V versus Li+/Li by using a highly concentrated electrolyte of lithium bis(fluorosulfonyl)amide (LiFSA). The corrosion prevention mechanism can be interpreted in relation to a remarkable change in solution structures at a certain threshold concentration. It is demonstrated that highly concentrated LiFSA/acetonitrile electrolyte enables highly reversible charge–discharge cycling of a 4 V‐class LiMn2O4/Li cell at a higher rate (ca. 50 % capacity retention at 20 C compared to C/2) than a state‐of‐the‐art commercial electrolyte (<20 %), thus providing a new design strategy for electrolyte materials in high‐rate lithium‐ion batteries.
Lanthanide Complexes with Multidentate Oxime Ligands as Single‐Molecule Magnets and Atmospheric Carbon Dioxide Fixation Systems
Authors: Hołyńska Małgorzata , Clérac Rodolphe , Rouzières Mathieu 
Published: July 2015

AbstractThe synthesis, structure, and magnetic properties of five lanthanide complexes with multidentate oxime ligands are described. Complexes 1 and 2 (1: [La2(pop)2(acac)4(CH3OH)], 2: [Dy2(pop)(acac)5]) are synthesized from the 2‐hydroxyimino‐N‐[1‐(2‐pyridyl)ethylidene]propanohydrazone (Hpop) ligand, while 3, 4, and 5 (3: [Dy2(naphthsaoH)2(acac)4H(OH)]⋅0.85 CH3CN⋅1.58 H2O; 4: [Tb2(naphthsaoH)2(acac)4H(OH)]⋅0.52 CH3CN⋅1.71 H2O; 5: [La6(CO3)2(naphthsao)5 (naphthsaoH)0.5(acac)8(CO3)0.5(CH3OH)2.76H5.5(H2O)1.24]⋅2.39 CH3CN⋅0.12 H2O) contain 1‐(1‐hydroxynaphthalen‐2‐yl)‐ethanone oxime (naphthsaoH2). In 1–4, dinuclear [Ln2] complexes crystallize, whereas hexanuclear LaIII complex 5 is formed after fixation of atmospheric carbon dioxide. DyIII‐based complexes 2 and 3 display single‐molecule‐magnet properties with energy barriers of 27 and 98 K, respectively. The presence of a broad and unsymmetrical relaxation mode observed in the ac susceptibility data for 3 suggest two different dynamics of the magnetization which might be a consequence of independent relaxation processes of the two different Dy3+ ions.
Formal Asymmetric (4+1) Annulation Reaction between Sulfur Ylides and 1,3‐Dienes
Authors: Rousseau Olivier , Delaunay Thierry , Dequirez Geoffroy , Trieu‐Van Tran , Robeyns Koen , Robiette Raphaël 
Published: July 2015

AbstractA highly enantioselective synthesis of functionalized cyclopentanoids by a formal asymmetric (4+1) annulation strategy was developed. The methodology consists of a stereoselective cyclopropanation reaction between chiral sulfur ylides and 1,3‐dienes followed by a, in situ, stereospecific MgI2‐catalyzed rearrangement of vinylcyclopropanes. This method is distinguished by a remarkable compatibility with functional groups and a high stereocontrol.
Lehr‐ und Lernmaterialien zur Einführung naturwissenschaftlicher Arbeits‐ und Denkweisen bei Schülerinnen und Schülern mit Hörbeeinträchtigung
Authors: Adesokan Adejoke , Reiners Christiane S. 
Published: July 2015

AbstractDie Forderung nach einem differenzierten Umgang mit heterogenen Lerngruppen und einem inklusiven Schulsystem hat insbesondere durch die zunehmende Pluralität in deutschen Schulklassen und die Unterzeichnung der Behindertenrechtskonvention an Bedeutung gewonnen. Deutschland befindet sich derzeit auf dem Weg in ein inklusives Schulsystem, in dem alle Lernenden unabhängig von ihren individuellen Fähigkeiten und Begabungen gemeinsam beschult werden sollen. Um eine angemessene Förderung aller Lernenden ermöglichen zu können, ist eine differenzierte Kenntnis über individuelle Lernvoraussetzungen zur Gestaltung entsprechender Lernarrangements notwendig. Vor welchen Herausforderungen allerdings Lernende mit Förderbedarf beim Lernen von Chemie stehen und welche konkreten Konzepte in einem inklusiven Unterricht eingesetzt werden könnten, dazu liegen in der Chemiedidaktik bisher nur wenige Studien vor. Der vorliegende Beitrag beschreibt ein Projekt, dessen kurzfristiges Ziel es ist, spezifische Lernschwierigkeiten von Lernenden mit Förderbedarf im Chemieunterricht zu diagnostizieren. Um einen Einstieg in diese bisher kaum untersuchte Thematik zu finden, werden die Untersuchungen zunächst am Beispiel von Lernenden mit Hörbeeinträchtigung durchgeführt, um möglichst detaillierte und spezifische Erkenntnisse über diesen Förderschwerpunkt zu erzielen. Weiterhin zielt das Projekt auf die Entwicklung eines Förderkonzeptes zur Einführung naturwissenschaftlicher Arbeits‐ und Denkweisen ab, das auf die Bedürfnisse von Lernenden mit Hörbeeinträchtigung abgestimmt ist. Es steht zu erwarten, dass die entwickelte Konzeption langfristig einen Beitrag zur Entwicklung eines inklusiven Chemieunterrichtes leisten kann.
HPV DNA testing with cytology triage in cervical cancer screening: Influence of revealing HPV infection status
Authors: Richardson Lyndsay Ann , El‐Zein Mariam , Ramanakumar Agnihotram V. , Ratnam Samuel , Sangwa‐Lugoma Ghislain , Longatto‐Filho Adhemar , Cardoso Marly Augusto , Coutlée Francois , Franco Eduardo L. ,   The PEACHS (Pap Efficacy After Cervical HPV Status) Study Consortium
Published: July 2015

BACKGROUNDKnowledge of cervical human papillomavirus (HPV) status might influence a cytotechnician's assessment of cellular abnormalities. The authors compared original cytotechnicians' Papanicolaou (Pap) readings for which HPV status was concealed with Pap rereads for which HPV status was revealed separately for 3 screening populations.METHODSPreviously collected cervical Pap smears and clinical data were obtained from the Canadian Cervical Cancer Screening Trial (study A), the Democratic Republic of Congo Community‐Based Screening Study (study B), and the Brazilian Investigation into Nutrition and Cervical Cancer Prevention (study C). Smears were reread with knowledge of HPV status for all HPV‐positive women as well as a sample of HPV‐negative women. Diagnostic performance of Pap cytology was compared between original readings and rereads.RESULTSA total of 1767 Pap tests were reread. Among 915 rereads for HPV‐positive women, the contrast between “revealed” and “concealed” Pap readings demonstrated revisions from negative to positive results for 109 women (cutoff was atypical squamous cells of undetermined significance or worse) and 124 women (cutoff was low‐grade squamous intraepithelial lesions [LSIL] or worse). For a disease threshold of cervical intraepithelial neoplasia of grade 2 or worse, specificity significantly declined at the atypical squamous cells of undetermined significance cutoff for studies A (86.6% to 75.3%) and C (42.5% to 15.5%), and at the LSIL cutoff for study C (61.9% to 37.6%). Sensitivity remained nearly unchanged between readings, except in study C, in which reread performance was superior (91.3% vs 71.9% for the LSIL cutoff).CONCLUSIONSA reduction in the diagnostic accuracy of Pap cytology was observed when revealing patients' cervical HPV status, possibly due to a heightened awareness of potential abnormalities, which led to more false‐positive results. Cancer (Cancer Cytopathol) 2015;123:745–754. © 2015 American Cancer Society.
Faithful performance prediction of a dynamic task‐based runtime system for heterogeneous multi‐core architectures
Authors: Stanisic Luka , Thibault Samuel , Legrand Arnaud , Videau Brice , Méhaut Jean‐François 
Published: July 2015

SummaryMulti‐core architectures comprising several graphics processing units (GPUs) have become mainstream in the field of high‐performance computing. However, obtaining the maximum performance of such heterogeneous machines is challenging as it requires to carefully off‐load computations and manage data movements between the different processing units. The most promising and successful approaches so far build on task‐based runtimes that abstract the machine and rely on opportunistic scheduling algorithms. As a consequence, the problem gets shifted to choosing the task granularity, task graph structure, and optimizing the scheduling strategies. Trying different combinations of these different alternatives is also itself a challenge. Indeed, obtaining accurate measurements requires reserving the target system for the whole duration of experiments. Furthermore, observations are limited to the few available systems at hand and may be difficult to generalize. In this article, we show how we crafted a coarse‐grain hybrid simulation/emulation of StarPU, a dynamic runtime for hybrid architectures, over SimGrid, a versatile simulator of distributed systems. This approach allows to obtain performance predictions of classical dense linear algebra kernels accurate within a few percents and in a matter of seconds, which allows both runtime and application designers to quickly decide which optimization to enable or whether it is worth investing in higher‐end graphics processing units or not. Additionally, it allows to conduct robust and extensive scheduling studies in a controlled environment whose characteristics are very close to real platforms while having reproducible behavior. Copyright © 2015 John Wiley & Sons, Ltd.
An Acid/Base‐Regulated Recyclable Strategy for Homogeneous Cinchona Alkaloid‐Derived Primary Amine Organocatalysts in Aldol, Vinylogous Michael and Double‐Michael Cascade Reactions
Authors: Wan Jingwei , Zhao Zhiwei , Wang Falu , Ma Xuebing 
Published: July 2015

AbstractA practical, recyclable strategy for homogeneous cinchona alkaloid‐derived primary amine organocatalysts was developed by controlling the solubilities in an aqueous/organic biphasic system through regulating the pH of the aqueous phase, effecting the protonation and deprotonation of primary amino, tertiary amino and pyridyl groups. By means of model aldol, vinylogous Michael and double‐Michael cascade reactions, the reusability of the organocatalysts epi‐CDNH2, DeMe‐QNNH2 and H‐CDNH2 over three cycles was investigated in detail. It was found that the organocatalysts were highly effective with respect to catalytic performance, including the yields and stereoselectivities. Furthermore, the recovered organocatalysts in the tenth cycle retained similar excellent enantioselectivities to fresh organocatalysts. However, the formation of inactive intermediates between organocatalyst and reactants resulted in decreased yields.
Insights into the Synthesis and the Solution Behavior of meso‐Aryloxy‐ and Alkoxy‐Substituted Porphyrins
Authors: Birin Kirill P. , Gorbunova Yulia G. , Tsivadze Aslan Yu. , Bessmertnykh‐Lemeune Alla G. , Guilard Roger 
Published: July 2015

Abstractmeso‐RO‐appended (R = alkyl, aryl) porphyrins bearing one or two OR substituents at the tetrapyrrolic macrocycle were synthesized in good yields from 5,15‐dibromo‐10,20‐diphenylporphyrins 2H(Br2DPP), Ni(Br2DPP) and Zn(Br2DPP) using an SNAr reaction. By varying the solvent, the base, the temperature, and the time of the reaction, the optimum conditions were established, and the selective introduction of one or two meso‐RO substituents at the periphery of the macrocycle was achieved. Moreover, monofunctionalization of Ni(Br2DPP) according to an SNAr reaction was used as a key step for the synthesis of rarely explored unsymmetrical porphyrinyl alkyl ethers. 1H NMR studies of these ethers in CDCl3 revealed concentration‐dependent aggregation of the zinc derivative through coordination of the central metal ion of one molecule to the peripheral oxygen atom of a second tetrapyrrolic macrocycle.
Iron‐Catalyzed Acylative Dealkylation of N‐Alkylsulfoximines
Authors: Lamers Philip , Priebbenow Daniel L. , Bolm Carsten 
Published: July 2015

AbstractAs a result of our recent investigations into the N‐functionalization of sulfoximines, an iron‐catalyzed dealkylative acylation of N‐alkylsulfoximines has been developed. This process involves a Polonovski‐type dealkylation of an N‐alkylated sulfoximine to afford a reactive intermediate that is trapped in the presence of a suitable aldehyde or anhydride to afford N‐acyl‐ and N‐aroylsulfoximine derivatives in one pot. Subsequent cleavage of the acyl or aroyl group under acidic conditions generates a synthetically valuable NH‐sulfoximine.
Coupled Gas–Liquid Two‐Phase Model in Perforated Vertical Wells for Petroleum and Natural Gas
Authors: Hu Jiancheng 
Published: July 2015

AbstractA reservoir wellbore model that couples pressure drop and flow rate is developed based on a homogeneous model for a gas–liquid two‐phase flow in a perforated vertical well. The perforation pressure drop, liquid holdup, and inflow along the depth of the perforated vertical well are studied. The total pressure drop in a perforated vertical wellbore is made up of acceleration, wall friction, and gravity pressure drop. The model is applied to a high‐pressure, high‐temperature infinite and finite conductivity gas well, and an iterative scheme is employed to solve the coupling mode.
Fabrication of Carbon Nanotube/Indium Tin Oxide “Inverse Tandem” Absorbing Coatings with Tunable Spectral Selectivity for Solar–Thermal Applications
Authors: Bera Raj Kumar , Azoubel Suzanna , Mhaisalkar Subodh Gautam , Magdassi Shlomo , Mandler Daniel 
Published: July 2015

AbstractWe report the fabrication of a new selective “inverse tandem” absorbing coating based on carbon nanotube (CNT)/indium‐tin oxide (ITO) on aluminium (Al) for mid‐temperature solar–thermal application. The CNT layer is formed by spraying and functions as an excellent solar absorber whereas the ITO layer produced on top of the CNTs by sputtering serves as an IR reflector. The effect of the thickness of the ITO on the spectral selectivity of the absorbing coating was investigated. Controlling the thickness of ITO allowed the spectral selectivity of the coating to be tuned. The CNT/ITO solar coatings with optimized thickness of ITO showed excellent spectral selectivity values of absorptance (α) of 0.927 and emittance (ε) of 0.2. The performance of the coatings at high temperature after heating in air in the range of 25–300 °C for different durations was also investigated. The performance and structure of the CNT/ITO coating was also compared with the wet deposition method in which the ITO coating was formed by spraying.
The fluvial flux of particulate organic matter from the UK: the emission factor of soil erosion
Authors: Worrall Fred , Burt Tim P. , Howden Nicholas J.K. 
Published: July 2015

AbstractSoil erosion has been identified as a potential global carbon sink since eroded organic matter is replaced at source and eroded material is readily buried. However, this argument has relied on poor estimates of the total fate of in‐transit particulates and could erroneously imply soil erosion could be encouraged to generate carbon stores. These previous estimates have not considered that organic matter can also be released to the atmosphere as a range of greenhouse gases, not only carbon dioxide (CO2), but also the more powerful greenhouse gases methane (CH4) and nitrous oxide (N2O). As soil carbon lost by erosion is only replaced by uptake of CO2, this could represent a considerable imbalance in greenhouse gas warming potential, even if it is not significant in terms of overall carbon flux. This work therefore considers the flux of particulate organic matter through UK rivers with respect to both carbon fluxes and greenhouse gas emissions. The results show that, although emissions to the atmosphere are dominated by CO2, there are also considerable fluxes of CH4 and N2O. The results suggest that soil erosion is a net source of greenhouse gases with median emission factors of 5.5, 4.4 and 0.3 tonnes CO2eq/yr for one tonne of fluvial carbon, gross carbon erosion and gross soil erosion, respectively. This study concludes that gross soil erosion would therefore only be a net sink of both carbon and greenhouse gases if all the following criteria are met: the gross soil erosion rate were very low (<91 tonnes/km2/yr); the eroded carbon were completely replaced by new soil organic matter; and if less than half of the gross erosion made it into the stream network. By establishing the emission factor for soil erosion, it becomes possible to properly account for the benefits of good soil management in minimizing losses of greenhouse gases to the atmosphere as a by‐product of soil erosion. Copyright © 2015 John Wiley & Sons, Ltd.
Lenalidomide and secondary acute lymphoblastic leukemia: a case series
Authors: Tan Marisela , Fong Richard , Lo Mimi , Young Rebecca 
Published: July 2015

AbstractLenalidomide is often used in the maintenance setting for multiple myeloma and has been linked to the development of secondary primary malignancies. The mechanism of lenalidomide causing secondary malignancies has not been fully elucidated, but case reports and phase 3 trials have captured this uncommon occurrence. A case series describing development of secondary acute lymphoblastic leukemia in patients receiving lenalidomide maintenance therapy is presented. Based on data published in the literature thus far and commonalities among patients in this case series, secondary acute lymphoblastic leukemia is likely duration related rather than dose related. Increased cognizance of this secondary malignancy will allow for a more accurate characterization of its true incidence. Regimens for acute lymphoblastic leukemia can be used for management of secondary acute lymphoblastic leukemia with plan for stem cell transplantation. Further studies are needed to identify risk factors for development of secondary malignancy and the best management approach for these patients. Copyright © 2015 John Wiley & Sons, Ltd.