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Numerical Algorithms - Our aim in this paper is to introduce an extragradient-type method for solving variational inequality with uniformly continuous pseudomonotone operator. The strong... 相似文献
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Ratnadip De Sabrina Gonglach Shounik Paul Michael Haas S. S. Sreejith Philipp Gerschel Ulf‐Peter Apfel Thanh Huyen Vuong Jabor Rabeah Soumyajit Roy Wolfgang Schfberger 《Angewandte Chemie (International ed. in English)》2020,59(26):10527-10534
The controlled electrochemical reduction of carbon dioxide to value added chemicals is an important strategy in terms of renewable energy technologies. Therefore, the development of efficient and stable catalysts in an aqueous environment is of great importance. In this context, we focused on synthesizing and studying a molecular MnIII‐corrole complex, which is modified on the three meso‐positions with polyethylene glycol moieties for direct and selective production of acetic acid from CO2. Electrochemical reduction of MnIII leads to an electroactive MnII species, which binds CO2 and stabilizes the reduced intermediates. This catalyst allows to electrochemically reduce CO2 to acetic acid in a moderate acidic aqueous medium (pH 6) with a selectivity of 63 % and a turn over frequency (TOF) of 8.25 h?1, when immobilized on a carbon paper (CP) electrode. In terms of high selectivity towards acetate, we propose the formation and reduction of an oxalate type intermediate, stabilized at the MnIII‐corrole center. 相似文献
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Continuous positive airway pressure (CPAP) devices are popularly used for obstructive sleep apnoea (OSA) treatment. However, the noise level emission from these devices has been identified as a potential factor for patient’s discomfort and rejection. There is a need to obtain information on the noise characteristics and source locations in order to tackle the most serious noise source within these devices. A typical CPAP device was used for the investigation and its sound characteristics and sound power levels were determined. The noise generated from a centrifugal fan was also independently investigated to address its contribution to the overall noise of the device. Frequency analysis suggested that the noise generated from both the CPAP device and the fan is broadband in nature with discrete peaks containing rotational and non-rotational components. The broadband components were then studied in detail using numerical simulation approach. Computational aeroacoustics (CAA) method with hybrid approach was used to a three-dimensional (3-D) CPAP fluid model to predict the aerodynamic and aeroacoustics behaviours of the device. This showed a complicated flow structure involving flow separation, rotation, and vortices in several locations which resulted in high level of flow turbulence inside the device. The turbulent components were used to estimate the broadband noise level at source using the broadband noise source (BNS) models. It shows the most critical location is at the fan region and at the fan inlet. 相似文献
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Thanh Binh Nguyen Thi Minh Ha Vuong Arnaud Martel Robert Dhal Gilles Dujardin 《Tetrahedron: Asymmetry》2008,19(17):2084-2087
A new practical approach to enantioenriched carboxy-differentiated aspartate derivatives was achieved in three steps via the 1,3-dipolar cycloaddition of N-benzyl-α-carbonyloxyethylnitrone with (R)-4-ethyl-N-vinyloxazolidin-2-one and chemoselective nucleophilic displacement of aspartimide under appropriate conditions (racemization less than 3%). 相似文献
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Over the past years a lot of attention was devoted to the investigation of isogeometric analysis, which integrates simulation techniques with computer aided design. In this article we focus on the ingredients for adaptive simulation with isogeometric methods. Local mesh refinement is realized by the usage of hierarchical B-splines, and different error estimation techniques are discussed. Promising numerical examples are shown in the end. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Chemistry of Natural Compounds - 相似文献
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