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排序方式: 共有1410条查询结果,搜索用时 15 毫秒
991.
Chien‐Pin Chou Aditya Wibawa Sakti Yoshifumi Nishimura Hiromi Nakai 《Chemical record (New York, N.Y.)》2019,19(4):746-757
The density‐functional tight‐binding (DFTB) method is one of the useful quantum chemical methods, which provides a good balance between accuracy and computational efficiency. In this account, we reviewed the basis of the DFTB method, the linear‐scaling divide‐and‐conquer (DC) technique, as well as the parameterization process. We also provide some refinement, modifications, and extension of the existing parameters that can be applicable for lithium‐ion battery systems. The diffusion constants of common electrolyte molecules and LiTFSA salt in solution have been estimated using DC‐DFTB molecular dynamics simulation with our new parameters. The resulting diffusion constants have good agreement to the experimental diffusion constants. 相似文献
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994.
We report the long-term results of 2 1/2-dimensional particle-in-cell simulations of the relativistic expansion of strongly magnetized electron-positron plasmas. When the simulation is carried to >150 light-crossing time of the initial plasma, the plasma pulse exhibits a number of remarkable properties. These include the repeated bifurcation of the pulse profile, development of a power-law momentum distribution with low-energy cutoff, and a simple scaling law for the peak Lorentz factor. 相似文献
995.
Batani D Strati F Stabile H Tomasini M Lucchini G Ravasio A Koenig M Benuzzi-Mounaix A Nishimura H Ochi Y Ullschmied J Skala J Kralikova B Pfeifer M Kadlec Ch Mocek T Präg A Hall T Milani P Barborini E Piseri P 《Physical review letters》2004,92(6):065503
We present an experimental point for the carbon equation of state (EOS) at megabar pressures, obtained by laser-driven shock waves. The rear side emissivity of "two-materials two-steps" targets (Al-C) was recorded with space and time resolution and, by applying the impedance mismatch method, allowed a direct determination of relative EOS points. Experiments were performed at the PALS and LULI laboratories using carbon samples with two different values of initial density, in order to explore a wider region of the phase diagram. Previously unreached pressures were obtained. The results are compared with previous experiments and with available theoretical models and seem to show a high compressibility of carbon at megabar pressures. 相似文献
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998.
Synthesis of [60]fullerene adducts bearing carbazole moieties by Bingel reaction and their properties 总被引:1,自引:0,他引:1
Carbazole-linked [60]fullerene adducts were successfully prepared by the Bingel reactions using carbazole derivatives bearing one or two ethyl malonate moieties. In the latter cases, specific bisadduct regioisomers were obtained, depending on the spacer unit between two ethyl malonate moieties. [reaction: see text] 相似文献
999.
A hydrofluoric acid (HF) bonding technique for multilayer thin films was studied to fabricate dielectric multilayer interference filters. The effects of pressure, HF concentration and annealing treatment on bonding strength were studied. Bonding strength of multilayer thin films of more than 5 MPa were obtained. In addition, a new type edge filter of 47 layers (47L) and a band-pass filter of 63 layers (63L), with their films sandwiched between glass substrates, were fabricated using this method. The measured transmittance spectra agreed well with the designed ones. 相似文献
1000.
Yoshikai K Hayama T Nishimura K Yamada K Tomioka K 《Chemical & pharmaceutical bulletin》2005,53(5):586-588
Treatment of formylalkenoates 1 and 7 with 2,2'-azobis(2-methylpropanenitrile) (AIBN) in the presence of dioxygen gave oxygenated carboxylic acids 5, 6, 8, 9 instead of acyl radical cyclization products, through preferential reaction of the corresponding acyl radicals with dioxygen rather than intramolecular attack to an enoate moiety. The reaction of 1 with AIBN in the absence of dioxygen recovered starting 1 in 98% yield. 相似文献