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51.
The research on the electrodes of Li-ion batteries aims to increase the energy density and the power density, improve the calendar and the cycling life, without sacrificing the safety issues. A constant progress through the years has been obtained owing to the surface treatment of the particles, in particular the coating of the particles with a layer that protects the core region from side reactions with the electrolyte, prevents the loss of oxygen, and the dissolution of the metal ions in the electrolyte, or simply improve the conductivity of the powder. The purpose of the present work is to review the different surface modifications that have been tried in the past for the different electrodes that are currently commercialized, or considered as promising, including the three families of positive electrodes (lamellar, spinel, and olivine families) and the three negative electrodes (carbon, Li4Ti5O12, and silicon). The role of the different coats used to improve either the surface conductivity, or the thermal stability, or the structural integrity is discussed. The limits in the efficiency of these different coats are also analyzed along with the understanding of the surface modifications that have been proposed. 相似文献
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Rupert L. Frank Elliott H. Lieb Julien Sabin 《Geometric And Functional Analysis》2016,26(4):1095-1134
We give a necessary and sufficient condition for the precompactness of all optimizing sequences for the Stein–Tomas inequality. In particular, if a well-known conjecture about the optimal constant in the Strichartz inequality is true, we obtain the existence of an optimizer in the Stein–Tomas inequality. Our result is valid in any dimension. 相似文献
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Triangle centers such as the center of gravity, the circumcenter, the orthocenter are well studied by geometers. Recently, under the guidance of Clark Kimberling, an electronic encyclopedia of triangle centers (ETC) has been developed, it contains more than 7000 centers and many properties of these points. In this paper, we describe how we created a certified version of ETC such that some of the properties described come along with a computer checked proof of its validity. 相似文献
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Detrimental Ni(0) transfer in Kumada catalyst transfer polycondensation of benzo[2,1‐b:3,4‐b']dithiophene 下载免费PDF全文
Anjan Bedi Julien De Winter Pascal Gerbaux Guy Koeckelberghs 《Journal of polymer science. Part A, Polymer chemistry》2016,54(12):1706-1712
This article deals with the Kumada Catalyst Transfer Polycondensation (KCTP) of 4,7‐dioctylbenzo[2,1‐b:3,4‐b']dithiophene ( BDP‐Oct ) using Ni(II) catalyst or In/cat combination. A combination of MALDI MS, GPC, and 31P NMR spectroscopy is used to reveal the failure of the KCTP of this particular monomer. Intermolecular transfer reactions to monomer appeared to prevent the formation of polymer. This result is remarkable, since isomeric benzo[1,2‐b:4,5‐b']dithiophene polymerizes in a controlled way. The presence of a “non‐aromatic double bond” in annulated monomers is discussed. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1706–1712 相似文献
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Corrigendum: An NMR‐Driven Crystallography Strategy to Overcome the Computability Limit of Powder Structure Determination: A Layered Aluminophosphate Case 下载免费PDF全文
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We study the properties of the ergosurface of the Pomeransky–Senkov black rings, and show that it splits into an “inner” and
an “outer” region. As for the singular set, the topology of the “outer ergosurface” depends upon the value of parameters. 相似文献
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Momodu Damilola Madito Moshawe Barzegar Farshad Bello Abdulhakeem Khaleed Abubakar Olaniyan Okikiola Dangbegnon Julien Manyala Ncholu 《Journal of Solid State Electrochemistry》2017,21(3):859-872
Journal of Solid State Electrochemistry - Activated carbon from tree bark (ACB) has been synthesized by a facile and environmentally friendly activation and carbonization process at different... 相似文献