bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production and wear property of electroless Ni-plated B4C-AstaloyCr-M composites
Authors: Yonetken Ahmet , Talaş Şükrü , Erol Ayhan , Gökoğlan Ömer , Mersin Taner 
Published: March 2014

AbstractNickel (Ni) matrix reinforced with boron carbide (B4C) has been produced by conventional furnace sintering at various temperatures. A uniform Ni layer on B4C powders was deposited prior to sintering using electroless plating technique, allowing close surface contact between particles. A composite consisting of quaternary additions, a ceramic phase, B4C, within a matrix of Ni and AstaloyCr-M powders has been prepared at a temperature range of 1000°C–1200°C under Ar shroud. X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) study, compressive testing, and hardness measurements were employed to characterize the properties of the composite. Experimental results showed that the best properties as compressive strength σmax and hardness (HB) were obtained at 1150°C. Wear resistance was relatively higher than cast iron.
Quantitative X-Ray Powder Diffraction Analysis of Portland Cements: Proficiency Testing for Laboratory Assessment
Authors: Stutzman Paul 
Published: March 2014

Abstract
Quantitative X-ray powder diffraction analysis (QXRD) is being used within the cement industry for phase characterization of hydraulic cement. The current ASTM standard test method for powder diffraction analysis of cements provides guidance, but not an explicit method, for quantifying phase concentrations. The standard utilizes qualification criteria, where an analysis of a set of certified reference materials must fall within stated precision and bias limits. Validation of X-ray powder diffraction analyses by the Rietveld method is particularly important because the normalization inherent in the mass fraction calculations can obscure accuracy problems. Currently, the only certified reference materials for phase abundance are a set of NIST SRM clinkers, which lack the calcium sulfate and carbonate phases found in portland cements. A set of portland cements was distributed to 29 laboratories for analysis according to each lab’s individual protocols. The objective was to provide each lab with quantitative feedback on its precision and accuracy performance. The results from all the labs are presented graphically with Youden plots that incorporate ranking to illustrate relative lab precision and accuracy based upon a consensus mean for each phase and ASTM C1365 performance qualification criteria. Labs that fall outside of the compliance limits are provided with information via the Youden plots to assess their systematic and random error. Proficiency testing of this sort provides participating laboratories with a quantitative assessment of their performance relative to peers using a wider range of materials encompassing the broad spectrum of modern hydraulic cement production. These newer materials may include, for example, the calcium sulfate phases and the limestone additions that have become commonplace in today’s cements. Such a quantitative assessment could be used to qualify laboratories and may be stipulated in a specification.
Stochastic Demography and the Neutral Substitution Rate in Class-Structured Populations
Authors: Lehmann Laurent 
Published: March 2014

Abstract
The neutral rate of allelic substitution is analyzed for a class-structured population subject to a stationary stochastic demographic process. The substitution rate is shown to be generally equal to the effective mutation rate, and under overlapping generations it can be expressed as the effective mutation rate in newborns when measured in units of average generation time. With uniform mutation rate across classes the substitution rate reduces to the mutation rate.
Randomized, Controlled Clinical Trial to Evaluate a Xenogeneic Collagen Matrix as an Alternative to Free Gingival Grafting for Oral Soft Tissue Augmentation
Authors: McGuire Michael K. , Scheyer E. Todd 
Published: March 2014

Background: The standard of care for increasing keratinized tissue (KT) and vestibular area is an autogenous free gingival graft (FGG) and vestibuloplasty; however, there is morbidity associated with the harvest of autogenous tissue, and supply is limited. The purpose of this study is to determine if a xenogeneic collagen matrix (CM) might be as effective as FGG.Methods: This study is a single‐masked, randomized, controlled, split‐mouth study of 30 patients with insufficient zones of KT (<2 mm). It uses a within‐patient treatment‐comparison design to establish non‐inferiority of the test (CM) versus control (FGG) therapy. The primary efficacy endpoint was change in KT width (∆KT) from surgery to 6 months post‐surgery. Secondary endpoints included traditional periodontal measures, such as clinical attachment level, recession, and bleeding on probing. Patient‐reported pain, discomfort, and esthetic satisfaction were also recorded. Biopsies were obtained at 6 months.Results: Surgery and postoperative sequelae were uneventful, with normal healing observed at both test and control sites. The primary outcome, ∆KT width at 6 months, did not establish non‐inferiority of CM compared to FGG (P = 0.9992), with the FGG sites averaging 1.5 mm more KT width than CM sites. However, the amount of new KT generated for both therapies averaged ≥2 mm. Secondary outcomes were not significantly different between test and control sites. All site biopsies appeared as normal mucoperiosteum with keratinized epithelium. CM sites achieved better texture and color matches, and more than two‐thirds of patients preferred the appearance of their CM sites.Conclusion: With the proviso of sufficient KT (≈2 mm in width) and study goals of lower morbidity, unlimited supply, and patient satisfaction, CM appears to be a suitable substitute for FGG in vestibuloplasty procedures designed to increase KT around teeth.
On ideal equal convergence
Authors: Filipów Rafał , Staniszewski Marcin 
Published: March 2014

AbstractWe consider ideal equal convergence of a sequence of functions. This is a generalization of equal convergence introduced by Császár and Laczkovich [Császár Á., Laczkovich M., Discrete and equal convergence, Studia Sci. Math. Hungar., 1975, 10(3–4), 463–472]. Our definition of ideal equal convergence encompasses two different kinds of ideal equal convergence introduced in [Das P., Dutta S., Pal S.K., On and *-equal convergence and an Egoroff-type theorem, Mat. Vesnik, 2014, 66(2), 165–177]_and [Filipów R., Szuca P., Three kinds of convergence and the associated I-Baire classes, J. Math. Anal. Appl., 2012, 391(1), 1–9]. We also solve a few problems posed in the paper by Das, Dutta and Pal.
Metric products and continuation of isotone functions
Authors: Dovgoshey O. , Petrov E. , Kozub G. 
Published: March 2014

Abstract
Let ℝ+ = [0,∞) and let A ⊆ ℝ+n. We have found the necessary and sufficient conditions under which a function Φ: A → ℝ+ has an isotone subadditive continuation on ℝ+n. It allows us to describe the metrics, defined on the Cartesian product X
1×...×X
n of given metric spaces $$\left( {X_1 ,d_{X_1 } } \right), \ldots ,\left( {X_n ,d_{X_n } } \right)$$, generated by the isotone metric preserving functions on ℝ+n. It is also shown that the isotone metric preserving functions Φ: ℝ+n → ℝ+ coincide with the first moduli of continuity of the nonconstant bornologous functions g: ℝ+n → ℝ+.
L'iconographie du temple de Markula devī au Lahoul
Authors: Diserens Hélène 
Published: March 2014

L'ancienne façade en bois sculpté du sanctuaire, ainsi que les panneaux du maṇḍapa et le plafond du temple de Markuladevī dans la vallée du Candrabhaga au Lahoul (Himachal Pradesh, Inde) comptent parmi les plus belles créations artistiques de la région.
L'absence de sources textuelles ou d'inscriptions est regrettable, car ce temple est un symbole majeur de la présence du vishnouïsme à la frontière nord-ouest du monde indien. H. Goetz a décrit ce temple dans son ouvrage The Early Wooden Temples of Chamba (1955, p. 90-100) illustré de photographies prises par l'ASI en 1904 et 1905. Il a identifié les reliefs de deux divinités sur un char tiré de sept chevaux, qui occupent la partie centrale de la façade, comme étant des images de Sūrya. Grâce aux progrès de nos connaissances sur l'art de l'ouest himalayen, ainsi qu'à l'accès aux photographies du WHAV, H. Diserens propose une autre solution et identifie aussi les autres divinités présentes sur ces reliefs.
L'iconographie de la façade du sanctuaire célèbre le retour victorieux de Vişņu rapportant l'amŗta, qui assure l'immortalité des dieux et leur supériorité sur les démons. Suivi de son fils Sāmba et de son escorte céleste, Vişņu est représenté dans sa double manifestation en tant que dieu suprême et divinité solaire, un aspect typiquement indien de l'āditya Vişņu. Autre témoignage de la présence de Vişņu en tant que dieu suprême : deux panneaux en bois sculptés illustrant l'un les exploits de l'avatāra Vāmana-Trivikrama, l'autre le Barattage de l'océan de lait. Une scène de ce dernier panneau oppose deux joueurs autour d'un damier. Son interprétation reste difficile.
Effect of Biofertilizer Addition on Nitrous Oxide Emission
Authors: Endah Retnaningrum  , Irfan D. Prijambada  , Sukarti Moeljopawiro  , Budi S. Daryono  
Published: March 2014

Application of nitrogen fixing biofertilizer, such as Azotobacter, has a potential for reducing nitrous oxide(N2O) emission. The aim of this study was to examine the effect of nitrogen fixing biofertilizer addition to common practices of urea and fresh cattle manure usages for maize (Zea mays L.) growing on N2O emission. The field experiment was conducted at GunungKidul, Yogyakarta, Indonesia. The treatments were addition of fresh cattle manure (M), fresh cattle manure added with nitrogen fixing biofertilizer (MB), urea (U), urea added with nitrogen fixing biofertilizer (UB), and control (no N fertilizer added). Nitrogen contents of the added urea and fresh cattle manure were adjusted to be equal. Urea and fresh cattle manure were given three times throughout the experiment period, i.e. 12, 30, and 48 days after planting (DAP). Urea was given at a rate of 44, 29, and 15 kg.ha-1, respectively while fresh cattle manure was given at a rate of 6000, 4000, and 2000 kg.ha-1, respectively. The emitted N2O was collected using a closed-chamber method at 24, 42, 60, and 72 DAP and were determined using Gas Chromatograph. Soil properties including available N (NH4+-N and NO3–-N) and organic C contents were also analyzed. On the harvesting time, the harvest index and the grain yield were determined. Biofertilizer addition influence decomposition process of cattle manure and urea that led to mineralization and nitrification of residual organic matterand hence to cause soil NH4+N in the order concentration of M treatment > MB > U > UB>C, and soil NO3–-N of MB treatment > M > U > UB>C. Reduction of NO3–N was resulted in the highest N2O emission of M >U>MB>UB>C(P < 0.01). The grain yield, and harvest index of maize wereresulted in the order value of MB> UB > U > M>C treatments.Available mineral N and soil organic C contents strongly affected N2O emission (P < 0.01).The results suggested that biofertilizer addition to common agricultural practices reduce N2O emission and simultaneusly increased grain yield, and harvest index of maize.
Three‐dimensional GPS ionospheric tomography over Japan using constrained least squares
Authors: Seemala Gopi K. , Yamamoto Mamoru , Saito Akinori , Chen Chia‐Hung 
Published: March 2014

AbstractA new three‐dimensional GPS ionospheric tomography technique is developed that uses total electron content (TEC) data from the dense Global Position System (GPS) receiver network, GPS Earth Observation Network (GEONET) in Japan, and it will not require an ionospheric model as the initial guess that will bias the reconstruction of electron density. The GEONET is operated by Geospatial Information Authority of Japan and consists of more than 1200 receivers; this high density and wide coverage helps to reconstruct the electron density distribution in the ionosphere with high spatial resolution. This tomography technique uses a constrained least squares fit to reconstruct the three‐dimensional electron density distributions. This method is different to most other techniques as they require a background ionospheric model as an initial guess that could bias the reconstructed electron density. It rather uses a prior condition that the electron density should not exceed a certain value that is determined by the restrain parameter, which is derived from the NeQuick model. Its independency of the initial guess from a model will make it useful even in disturbed conditions. This paper presents results that are obtained by using this new tomographic technique. The reconstruction of three‐dimensional ionospheric tomograms is demonstrated using the GPS data, and the reliability and robustness are checked with simulated tomograms obtained using the synthetic GPS‐TEC data produced using NeQuick model.
Transferring Lithium Ions in Nanochannels: A PEO/Li+ Solid Polymer Electrolyte Design
Authors: Yang Ling‐Yun , Wei Da‐Xiu , Xu Min , Yao Ye‐Feng , Chen Qun 
Published: March 2014

AbstractA new category of crystalline polymer electrolyte prepared by the supramolecular self‐assembly of polyethylene oxide (PEO), α‐cyclodextrin (α‐CD), and LiAsF6 is reported. The polymer electrolyte consists of the nanochannels formed by α‐CDs in which the PEO/Li+ complexes are confined. The nanochannels formed by α‐CD provide the pathway for the directional motion of Li+ ions and at the same time prevent the access of the anions by size exclusion, resulting in good separation of the Li+ ions and the anions. The conductivity of the reported material is 30 times higher than that of the comparable PEO/Li+ complex crystal at room temperature. By using state‐of‐art solid‐state NMR spectroscopy, the structure and dynamics of the material were investigated in detail. The dynamics of the Li+ ions was studied and correlated to the ionic conductivity of the material.
Templated Synthesis of Nitrogen‐Enriched Nanoporous Carbon Materials from Porogenic Organic Precursors Prepared by ATRP
Authors: Wu Dingcai , Li Zhenghui , Zhong Mingjiang , Kowalewski Tomasz , Matyjaszewski Krzysztof 
Published: March 2014

AbstractA facile templated synthesis of functional nanocarbon materials with well‐defined spherical mesopores is developed using all‐organic porogenic precursors comprised of hairy nanoparticles with nitrogen‐rich polyacrylonitrile shells grafted from sacrificial cross‐linked poly(methyl methacrylate) cores (xPMMA‐g‐PAN). Such shape‐persistent all‐organic nanostructured precursors, prepared using atom transfer radical polymerization (ATRP), assure robust formation of template nanostructures with continuous PAN precursor matrix over wide range of compositions, and allow for removal of the sacrificial template through simple thermal decomposition. Carbon materials prepared using this method combine nitrogen enrichment with hierarchical nanostructure comprised of microporous carbon matrix interspersed with mesopores originating from sacrificial xPMMA cores, and thus perform well as CO2 adsorbents and as supercapacitor electrodes.
Filaggrin‐Peptide mit β‐Haarnadel‐Struktur binden Rheuma‐Antikörper
Authors: Fischer Sabrina , Geyer Armin 
Published: March 2014

AbstractIn ELISA‐Tests zur Früherkennung von rheumatoider Arthritis (RA) dienen synthetische Filaggrin‐Peptide als Antigene für rheumaspezifische Autoantikörper (“anti‐citrullinated peptide antibody”, ACPA). Hier wird ein Peptid vorgestellt, welches das Bindungsepitop von ACPA in Form einer stabil faltenden β‐Haarnadel‐Struktur präsentiert. NMR‐Spektroskopie belegt die Homogenität der Faltung des Peptids, und so kann erstmals ein Strukturvorschlag für die antikörpergebundene Konformation des Epitops erstellt werden.
Ubiquinone‐Rhodol (UQ‐Rh) for Fluorescence Imaging of NAD(P)H through Intracellular Activation
Authors: Komatsu Hirokazu , Shindo Yutaka , Oka Kotaro , Hill Jonathan P. , Ariga Katsuhiko 
Published: March 2014

AbstractThe nicotinamide adenine dinucleotide (NAD) derivatives NADH and NADPH are critical components of cellular energy metabolism and operate as electron carriers. A novel fluorescent ubiquinone‐rhodol derivative (UQ‐Rh) was developed as a probe for NAD(P)H. By using the artificial promoter [(η5‐C5Me5)Ir(phen)(H2O)]2+, intracellular activation and imaging of NAD(P)H were successfully demonstrated. In contrast to bioorthogonal chemistry, this “bioparallel chemistry” approach involves interactions with native biological processes and could potentially be used to control or investigate cellular systems.
Divergent Total Syntheses of Lyconadins A and C
Authors: Yang Yang , Haskins Christopher W. , Zhang Wandi , Low Pui Leng , Dai Mingji 
Published: March 2014

AbstractDivergent and concise total syntheses of two lycopodium alkaloids, lyconadins A and C have been developed. The synthesis of lyconadin A, having potent neurotrophic activity, features an efficient one‐pot ketal removal and formal aza‐[4+2] cyclization to form the cagelike core structure. A tandem ketal removal/Mannich reaction was developed to build the tricyclic structure of lyconadin C. Both lyconadins A and C were synthesized from a pivotal intermediate.
Electronic Metal–Support Interactions in Single‐Atom Catalysts
Authors: Hu Pingping , Huang Zhiwei , Amghouz Zakariae , Makkee Michiel , Xu Fei , Kapteijn Freek , Dikhtiarenko Alla , Chen Yaxin , Gu Xiao , Tang Xingfu 
Published: March 2014

AbstractThe synthesis of single‐atom catalysts and the control of the electronic properties of catalytic sites to arrive at superior catalysts is a major challenge in heterogeneous catalysis. A stable supported single‐atom silver catalyst with a controllable electronic state was obtained by anti‐Ostwald ripening. An electronic perturbation of the catalytic sites that is induced by a subtle change in the structure of the support has a strong influence on the intrinsic reactivity. The higher depletion of the 4d electronic state of the silver atoms causes stronger electronic metal–support interactions, which leads to easier reducibility and higher catalytic activity. These results may improve our understanding of the nature of electronic metal–support interactions and lead to structure–activity correlations.
Supramolecular Complexes of Multivalent Cholesterol‐Containing Polymers to Solubilize Carbon Nanotubes in Apolar Organic Solvents
Authors: Nguendia Jules Zeuna , Zhong Weiheng , Fleury Alexandre , De Grandpré Guillaume , Soldera Armand , Sabat Ribal Georges , Claverie Jerome P. 
Published: March 2014

AbstractCopolymers of 2‐ethylhexyl acrylate (EHA) and cholesteryloxycarbonyl‐2‐hydroxymethacrylate (CEM) were prepared by reversible addition–fragmentation chain‐transfer (RAFT) polymerization. Supramolecular complexes of these copolymers with carbon nanotubes (CNTs) were soluble in THF, toluene, and isooctane. The colloidal solutions remained stable for months without aggregation. The rationale for the choice of CEM was based on the high adsorption energy of cholesterol on the CNT surface, as computed by DFT calculations. Adsorption isotherms were experimentally measured for copolymers of various architectures (statistical, diblock, and star copolymers), thereby demonstrating that 2–5 cholesterol groups were adsorbed per polymer chain. Once the supramolecular complex had dried, the CNTs could be easily resolubilized in isooctane without the need for high‐power sonication and in the absence of added polymer. Analysis by atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) indicated that the CNTs were devoid of bundles. The supramolecular complexes could also be employed in an inverse emulsion polymerization of 2‐hydroxyethylmethacrylate (HEMA) in isooctane and dodecane, thereby leading to the formation of a continuous polymeric sheath around the CNTs. Thus, this technique leads to the formation of very stable dispersions in non‐polar organic solvents, without altering the fundamental properties of the CNTs.
Base‐Catalyzed NN Bond Cleavage of Hydrazones: Synthesis of α‐Amino Ketones
Authors: Tang Hai‐Tao , Zhou Yun‐Bing , Zhu Yu , Sun Hong‐Chao , Lin Min , Zhan Zhuang‐Ping 
Published: March 2014

AbstractAn efficient Cs2CO3‐promoted synthesis of α‐amino ketones using hydrazines, aldehydes, and α‐haloketones as starting materials through a cascade condensation/nucleophilic substitution/NN bond cleavage route is developed. The carbonyl group plays a key role in this novel NN bond cleavage process.
Preparation of Nitrogen‐Doped Porous Carbon Nanofibers and the Effect of Porosity, Electrical Conductivity, and Nitrogen Content on Their Oxygen Reduction Performance
Authors: Yang Dae‐Soo , Chaudhari Sudeshna , Rajesh Kizhakke Palleeri , Yu Jong‐Sung 
Published: March 2014

AbstractNitrogen‐doped carbon nanostructures are considered as a possible alternative to platinum‐based catalysts for fuel cells. The surface density of catalytic sites, electrical conductivity, and nitrogen content play important roles in designing electrode materials for fuel cells. Herein, N‐doped carbon fibers are prepared by electrospinning the poly(acrylonitrile) (PAN) solution followed by carbonization. Some of the key issues of the oxygen reduction reaction (ORR) are addressed in terms of nitrogen content, porosity, and electrical conductivity in the N‐containing carbon nanofibrous system. Nitrogen content and the amount of the graphitic phase are varied by changing the carbonization temperature. In addition, N‐doped carbon fibers with high porosity are prepared by electrospinning the solution mixture of poly(ethylene oxide) (PEO)/PAN followed by carbonization, and the porosity is tuned by varying the ratio of PEO to PAN. The effect of porosity or the surface density of catalytic sites on the ORR is studied. A medium porous sample prepared from the PEO/PAN mixture in a 1:1 ratio by carbonization at 1000 °C is found to be favorable for improved ORR performance for such a system. The observations made herein are explained in terms of trade‐offs between electrical conductivity, nitrogen content, and surface density of active sites.
Numerical Simulation of Oil‐Water Core Annular Flow in a U‐Bend Based on the Eulerian Model
Authors: Jiang Fan , Wang Yijun , Ou Jiajie , Chen Conggui 
Published: March 2014

AbstractThe oil‐water core annular flow through a U‐bend is simulated by computational fluid dynamics based on the Eulerian model. More flow parameters and the effect of annulus thickness on core annular flow are discussed. Conformity between the simulated and experimental data is observed. The development of oil‐water core annular flow in the U‐bend is analyzed, and the distributions of pressure and velocity are discussed. Results of the Eulerian model and volume‐of‐fluid (VOF) model are compared and the influence of oil properties on total pressure gradient is investigated. The suitable range of annulus thickness is identified. The results provide suitable operation conditions for designing the U‐bend pipefitting.
Modelling of Reactive Drying Processes Using the Example of Spray Polymerisation
Authors: Säckel Winfried , Nieken Ulrich 
Published: March 2014

AbstractReaktive Sprühtrocknungsprozesse wie Sprühpolymerisationen sind im Hinblick auf die Prozessintensivierung sehr interessant. Bisherige Forschungsarbeiten dazu basieren allerdings fast ausschließlich auf Experimenten. In diesem Beitrag wird ein Einzeltropfenmodell der Sprühpolymerisation vorgestellt, welches das Reaktions‐Diffusions‐System innerhalb eines Tropfens im Spray eindimensional ortsaufgelöst abbildet. Somit lassen sich Auswirkungen der Prozessparameter und Materialeigenschaften auf das Polymerisationsergebnis und wichtige Kenngrößen wie Zahlen‐ und Massenmittel der Kettenlängenverteilung abschätzen.