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Numerical simulation of lithium‐ion battery performance considering electrode microstructure 下载免费PDF全文
A spatially resolved three‐dimensional microscale model of a lithium‐ion battery half‐cell is developed and applied to periodic electrode microstructures made up of spherical particles following a bidisperse particle size distribution. The geometries of the periodic unit cells are derived from discrete element simulations using periodic boundary conditions. Three different particle arrangements, which consist of two layered structures and one mixed particle array, as well as three different compression rates, are considered. In the study, the cathode is assumed to consist of LiMn2O4 as active material. Layered particle arrangements comprising the particle fraction of the smaller particle size in the region close to the separator are found to be beneficial especially for high‐rate applications. According to the simulation results, the high‐rate capability is reduced upon compression of the electrode microstructures. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Changjun Li Changjie Ji Ronnier Luo Manuel Melgosa Michael H. Brill 《Color research and application》2015,40(1):30-39
Here, we investigated the CAT02 and HPE triangles in both x,y and u′,v′ spaces. It was found that in u′,v′ space, the HPE triangle is separated into two regions by the line 3u′ ? 8v′ + 6 = 0, which is the u′,v′ image of X + Y + Z = 0 under the mapping from (X,Y,Z) to (u′,v′). One of these two regions admits all‐positive R,G,B triplets and the other all‐negative R,G,B triplets, under the case of (X + Y + Z) > 0. The findings of this study explained the computation problems of CAT02 and provided methods for solving the Yellow‐Blue and Purple problems simultaneously. © 2013 Wiley Periodicals, Inc. Col Res Appl, 40, 30–39, 2015 相似文献
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Variations of Incomplete Open Cubes is the major project by the twentieth-century conceptual artist Sol LeWitt. In this paper we interpret the enumerative component of the project as embeddings of graphs. This formulation permits use of an algorithm to check the completeness of the list of the structures produced by the artist. Our conclusion is that the artist found the correct number of structures (that is, 122), but that his list contains a mistake in the presentation of a pair of incomplete cubes, a discovery that appears not to have been noted before. 相似文献
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Long Zhang Yichao Huang Fengjiang Sun Da Chen Michael Netzel Heather E. Smyth Yasmina Sultanbawa Yongfeng Deng Mingliang Fang Daniel Cozzolino 《International Journal of Food Science & Technology》2021,56(6):2621-2627
The objective of this study was to evaluate the effect of sample presentation (tissue type) and maturity (ripe and unripe) on the classification of banana (Musa Cavendish) samples sourced from two different geographical regions and analysed using mid infrared (MIR) spectroscopy. The coefficient of determination (R2) and the standard error of cross-validation (SECV) obtained using partial least squares discriminant analysis were 0.83 (0.33), 0.75 (0.25) and 0.94 (0.19) for the prediction of maturity, geographical origin and tissue type, respectively. No effect of either of type of tissue (e.g. pulp or peel) or maturity was observed. The results of this study demonstrated that MIR spectroscopy might be used to classify the origin of the banana samples at different degrees of ripeness. However, one of the limitations of this study is on the number of samples analysed and further validation must be recommended using samples from other sources, regions and harvest seasons. 相似文献
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Qiuping Wang Bojan Šarkanj Jasna Jurasovic Yusuf Chisti Michael Sulyok Jiashun Gong Sarote Sirisansaneeyakul Draženka Komes 《International Journal of Food Science & Technology》2019,54(5):1541-1549
Theabrownins (TB) are polymeric phenolic compounds associated with the multiple bioactivities of Pu-erh tea, a post-fermented Chinese dark tea. High-TB instant Pu-erh tea was produced via a novel submerged fermentation (SF) using Aspergillus tubingensis and compared with samples produced commercially via the conventional solid-state fermentation (SSF). Viable microorganisms and microbial toxins, especially aflatoxins B1, G1, B2, G2, cyclopiazonic acid, fumonisins B1, B2, B3 and ochratoxin A, were below the detection limit in all samples. Fewer microbial metabolites were found in SF instant tea compared with the SSF teas. Based on an adult consuming 1 g of instant Pu-erh tea daily, the dietary intake of investigated elements was below the safe limits recommended by various authorities. Tasters viewed the instant tea infusions as very mild, smooth, mellow and full. This suggested that submerged fermentation using A. tubingensis offers a speedy and safe alternative to commercial production of instant Pu-erh tea. 相似文献
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Wibke Exner Robert Hein Thorsten Mahrholz Peter Wierach Hans Peter Monner Michael Sinapius 《应用聚合物科学杂志》2019,136(5):47031
This article investigates the potential of aluminum oxide nanoparticles for the reduction of process-induced distortions of carbon fiber reinforced plastics (CFRP). Therefore the matrix properties, which affect the distortions, are experimentally and mechanistically analyzed in detail at various particle contents. The results clearly show an increasing impact of raised particle content on gelation, chemical and thermal shrinkage, on Young's modulus, as well as on Poisson's ratio. These alterations can be successfully transferred to reduce spring-in of L-shaped CFRP brackets, which are manufactured by infusion technology. However, it is found that particle contents higher than 5 wt % are needed to influence these parameters. For further understanding of the parameters controlling spring-in, a numerical sensitivity analysis is performed by the correlation of various matrix parameters and the induced distortions. The results from a structural simulation reveal that changes in thermal and chemical shrinkage as well as in gelation have a major impact on the distortions, but the modes of action of the particles also have to be taken into consideration. These mechanistical insights about nanoparticle impacts might be a valuable approach to lower or overcome distortions in composite materials in the future. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47031. 相似文献