1,720,993 research outputs found
Nanosized silver bromide: an efficient catalyst for alcohol oxidation in the presence of a multinuclear silver complex
No full textUpon investigating a silver-based complex for the alcohol oxidation reaction, we found AgBr as a new and efficient catalyst for the reaction in the presence of oxone (2KHSO(5)KHSO(4)K(2)SO(4)). The catalyst was characterized by scanning electron microscopy, energy dispersive spectrometry, transmission electron microscopy, dynamic light scattering, X-ray diffraction, chronoamperometry, X-ray photoelectron spectroscopy, and liquid chromatography-electrospray ionization mass spectrometry. We propose that nanosized silver bromide can be used as a catalyst for the oxidation of alcohol to aldehyde in the presence of oxone (2KHSO(5)KHSO(4)K(2)SO(4)) as an oxidant
Nanosized rhodium oxide for water oxidation: An organometallic precursor for the preparation of rhodium oxide
No full textElectrochemical production of hydrogen from water splitting is a promising process to allow storage of intermittent energies. However, anodic water oxidation, which is a complicated four-proton, four-electron transfer process, affects the efficiency of hydrogen generation due to the need to apply large overpotentials. Herein, we synthesized nanosized rhodium(III) oxide by the thermal decomposition of a known rhodium organometallic precursor and characterized it using scanning and transmission electron microscopies, powder X-ray diffraction, energy-dispersive X-ray, diffuse reflectance infrared and Fourier transform infrared spectroscopies, and electrochemical methods. The results showed that the nanosized rhodium oxide is a promising catalyst for water oxidation
Template free growth of robustly stable nanophotonic structures: broadband light superabsorbers
No full textProducing stable ultra-wideband light absorbers by a simple method is challenging for various applications such as solar energy harvesting, thermal regulation and suppression of stray light. Nanostructured refractory materials possess exceptional features enabling them to manipulate incident photons at the subwavelength scale and withstand against severe conditions. Here, we report a sputtering technique-based route to fabricate robustly stable TiAlN black absorbing coatings with a vertically aligned columnar structure, as a unique approach to produce large area metamaterials. The fabrication process is simple, free of any sophisticated patterning approach, substrate-independent, viable and scalable. Robust stability in adverse environments is an exceptional feature of these superabsorbers. Broadband (200-2500 nm) absorption of 89% is achieved from a single TiAlN layer and is increased to 95% after grading with thin anti-reflecting layers. The proposed sputtering based fabrication process would open a new platform to design, prepare and integrate nanophotonic structures, having applications in energy, electronic and optical sectors
Corrosion behavior of sintered CeNdFeB magnets in different solutions
No full textThe capability of CeNdFeB as a substitute for NdFeB is of considerable interest due to its cost effectiveness and fascinating magnetic properties. In this paper, we have systematically investigated the corrosion behavior of the sintered CeNdFeB magnets in alkaline and acidic media in order to evaluate their commercial viability. Electrochemical and immersion tests have been conducted using sintered CeNdFeB magnets with different amounts of Ce (0.0 wt%, 29.6 wt%, 44.6 wt%, 54.8 wt%) as substitution of Nd in different concentrations of sodium hydroxide (NaOH), nitric acid (HNO3), hydrochloric acid (HCl), sulfuric acid (H2SO4), and oxalic acid (H2C2O4). We have found that the sintered CeNdFeB magnets exhibit passive behavior and the corrosion rate decreases in NaOH and H2C2O4 solutions by comparison with sintered NdFeB magnets. When exposed in strong acids, the sintered CeNdFeB has comparable corrosion properties with sintered NdFeB in HNO3 solution and lower anticorrosion properties in HCl and H2SO4 solutions. (C) 2017 Elsevier B.V. All rights reserved
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Efficient and stable electrocatalyst for hydrogen evolution reaction prepared by hybrid technique in surface engineering: Electrochemical and magnetron sputtering methods
No full textDeveloping low-cost, stable, and robust electrocatalysts is significant for high effective hydrogen evolution reaction (HER). In this work, a coating system with Cu2O/NiMoCu on stainless steel (SS) is employed as a highly active and stable catalyst for HER in acidic solutions. Electrochemical measurements for as-designed system on SS show a low onset overpotential, small Tafel slope of similar to 32 mV/decade and long-term durability over 7 days of HER operation. To further inspections of electrocatalytic behavior of as-prepared system in HER, the EIS measurements are performed at several overpotentials and temperatures. It is found that high hydrogen evolution activity and stability of Cu2O/NiMoCu hybrid is likely due to special morphology of Cu2O which result in large number of active sites for hydrogen adsorption, and a synergetic effect giving electronic structure suitable for the HER. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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