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1.
Srivastava  Vivek 《Catalysis Letters》2021,151(12):3704-3720
Catalysis Letters - We gave an effective protocol to support Ru NPs on amine-functionalized SBA-15 mesoporous silica to catalyze the CO2 hydrogenation reaction. The amine groups present in the...  相似文献   
2.

ResearchGate has emerged as a popular professional network for scientists and researchers in a very short span. Similar to Google Scholar, the ResearchGate indexing uses an automatic crawling algorithm that extracts bibliographic data, citations, and other information about scholarly articles from various sources. However, it has been observed that the two platforms often show different publication and citation data for the same institutions, journals, and authors. While several previous studies analysed different aspects of ResearchGate and Google Scholar, the quantum of differences in publications, citations, and metrics between the two and the probable reasons for the same are not explored much. This article, therefore, attempts to bridge this research gap by analysing and measuring the differences in publications, citations, and different metrics of the two platforms for a large data set of highly cited authors. The results indicate that there are significantly high differences in publications and citations for the same authors captured by the two platforms, with Google Scholar having higher counts for a vast majority of the cases. The different metrics computed by the two platforms also differ in their values, showing different degrees of correlation. The coverage policy, indexing errors, author attribution mechanism, and strategy to deal with predatory publishing are found to be the main probable reasons for the differences in the two platforms.

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3.
Scaling down to deep submicrometer (DSM) technology has made noise a metric of equal importance as compared to power, speed, and area. Smaller feature size, lower supply voltage, and higher frequency are some of the characteristics for DSM circuits that make them more vulnerable to noise. New designs and circuit techniques are required in order to achieve robustness in presence of noise. Novel methodologies for designing energy-efficient noise-tolerant exclusive-OR-exclusive- NOR circuits that can operate at low-supply voltages with good signal integrity and driving capability are proposed. The circuits designed, after applying the proposed methodologies, are characterized and compared with previously published circuits for reliability, speed and energy efficiency. To test the driving capability of the proposed circuits, they are embedded in an existing 5-2 compressor design. The average noise threshold energy (ANTE) is used for quantifying the noise immunity of the proposed circuits. Simulation results show that, compared with the best available circuit in literature, the proposed circuits exhibit better noise-immunity, lower power-delay product (PDP) and good driving capability. All of the proposed circuits prove to be faster and successfully work at all ranges of supply voltage starting from 3.3 V down to 0.6 V. The savings in the PDP range from 94% to 21% for the given supply voltage range respectively and the average improvement in the ANTE is 2.67X.  相似文献   
4.
Building useful systems with an ability to understand "real" natural language input has long been an elusive goal for Artificial Intelligence. Well-known problems such as ambiguity, indirectness, and incompleteness of natural language inputs have thwarted efforts to build natural language interfaces to intelligent systems. In this article, we report on our work on a model of understanding natural language design specifications of physical devices such as simple electrical circuits. Our system, called KA, solves the classical problems of ambiguity, incompleteness and indirectness by exploiting the knowledge and problem-solving processes in the situation of designing simple physical devices. In addition, KA acquires its knowledge structures (apart from a basic ontology of devices) from the results of its problem-solving processes. Thus, KA can be bootstrapped to understand design specifications and user feedback about new devices using the knowledge structures it acquired from similar devices designed previously.In this paper, we report on three investigations in the KA project. Our first investigation demonstrates that KA can resolve ambiguities in design specifications as well as infer unarticulated requirements using the ontology, the knowledge structures, and the problem-solving processes provided by its design situation. The second investigation shows that KA's problem-solving capabilities help ascertain the relevance of indirect design specifications, and identify unspecified relations between detailed requirements. The third investigation demonstrates the extensibility of KA's theory of natural language understanding by showing that KA can interpret user feedback as well as design requirements. Our results demonstrate that situating language understanding in problem solving, such as device design in KA, provides effective solutions to unresolved problems in natural language processing.  相似文献   
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Advanced high-energy plasma systems are being used to achieve the benefits of the high-velocity oxy-fuel (HVOF) system without losing the inherent advantages of plasma for coating of gas turbine parts. MCrAlY coatings play a very important role in the performance and reliability of gas turbine components. One of the important considerations for next generation of gas turbines, which have more demanding conditions and need to withstand ever increasing operating temperatures, is that they should possess very low oxygen content levels in the coating. Low oxygen content coatings are applied by the expensive low-pressure plasma spray (LPPS)/vacuum plasma spray (VPS) technique for critical components in aero- and land-based gas turbines. This work deals with the development of low-cost LPPS equivalent coatings (having low oxygen content) using the high-energy high-velocity plasma spray (HEHVPS) gun and inert gas shroud. A comparison has also been made with CoNiCrAlY coatings by HVOF.  相似文献   
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The aim of this study is to determine the effect of Nb5+ doping on PZT (65/35) based bulk materials in their structure, micro structure and electrical properties. The Nb content was chosen 0-9 mole%. These materials were prepared by conventional mixed oxide method. X ray diffraction studies suggest the compound to be of rhombohedral perovskite phase. Excess addition of Nb result in pyrochlore and fluorite phase develops in PZT (65/35) sample. Detailed studies of dielectric constant as a function of temperature (40degC to 500degC) and frequency (100 Hz to 1 MHz) suggest that the compounds undergo diffuse type of phase transition. Maximum dielectric constant and resistivity were found to be strongly dependent on doping and measuring frequencies. Using complex impedance analysis micro structural parameters such as bulk and grain boundary resistance, bulk charge carrier concentration and relaxation time were determined  相似文献   
9.
Poly(vinylbenzyltrimethylammonium chloride)‐graft‐cotton cellulose, an anion‐exchange matrix, was synthesized by a mutual radiation‐induced grafting technique with a 60Co γ‐radiation source. The grafted matrix was characterized by grafting yield estimation, elemental analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The grafting yield decreased with the increase in the dose rate. However, the grafting yield and nitrogen content of grafted samples increased almost linearly with an increase in the total irradiation dose. To evaluate the performance of the grafted anion‐exchange matrix, the protein adsorption and elution behavior were investigated in a continuous column process under various experimental conditions, with bovine serum albumin used as a model protein. The binding and elution behavior of the anion‐exchange matrix depended on different experimental parameters, such as the grafting yield, ionic strength, pH of the medium, and amount of protein loaded. From a breakthrough curve, the equilibrium binding capacity and elution percentage of the grafted anion‐exchange matrix were estimated to be 40 mg/g and 94%, respectively. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5512–5521, 2006  相似文献   
10.
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