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排序方式: 共有226条查询结果,搜索用时 31 毫秒
111.
应用电化学阻抗法测定了不同荷电状态 (SOC)和不同温度下MlNi3.75Co0 .65Mn0 .4 Al0 .2 金属氢化物电极中氢的扩散系数 .结果表明 :室温下该电极中氢的扩散系数随其荷电量的增大而减小 ,SOC为 5 0 %时氢的扩散系数随温度的升高而增大 ,相应的氢扩散活化能为 35kJ/mo 相似文献
112.
本文用恒电位阶跃法研究了不同放电深度 (DOD)和不同温度下贮氢合金MlNi3.75Co0 .6 5Mn0 .4 Al0 .2 中氢的扩散行为 .结果表明 :室温下该合金中氢的扩散系数随DOD的增大而增大 ,在5 0 %DOD的该合金中 ,氢的扩散系数随温度的升高而增大 ,扩散活化能为 19.87kJ/mol 相似文献
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114.
Jun Xia Zheng Nai Li Wang Hao Gao Hong Wei Liu Hai Feng Chen Ming Fan Xin Sheng Yao 《中国化学快报》2008,19(9):1093-1095
6-(5-Carboxyl-2-methoxyphenyl)-apigenin (1), a new flavonoid, was isolated from the 60% ethanol extract of Selaginella uncinata (Desv.) Spring. Its structure was established by spectroscopic methods. Compound 1 represents the first example of the flavonoids possessing a benzoic acid substituent at C-6. 相似文献
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A new kind of nano‐chitosan Schiff‐base Cu complexes with particle sizes of 350 nm were prepared by combination of nano‐chitosan, Cu and Schiff‐base, and characterized by FT‐IR spectra, TEM, DLS and elemental analysis. The modes and mechanism of interaction of the copper complexes with DNA were studied by the fluorescent probe method and electrophoresis analysis. The results suggest that the Cu complexes bound to DNA by electrostatic and intercalation modes. The anticancer activity of the Cu complexes was evaluated by Sulforhodamine B (SRB) assay in vitro. Nano‐chitosan and their Schiff‐base Cu complexes inhibited the growth of the liver cancer cell lines SMMC‐7721 in vitro. The inhibition rate of Schiff‐base Cu complexes was higher than that of nano‐chitosan. Nano‐chitosan combining with Schiff‐base and Cu improved their anticancer activity, which ascribed to the synergistic effect between the chitosan matrix and the planar construction of the Cu complexes. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
117.
Xin Liu Wu Li Xueying Nai Shaoju Bian Qingfen Meng Dandan Gao Ming Wei 《Crystal Research and Technology》2012,47(4):455-460
4ZnO·B2O3·H2O whiskers were prepared from 2ZnO·3B2O3·3.5H2O under hydrothermal process at 160 °C for 10 h. The synthesized product was characterized by XRD, SEM, TG‐DSC and FT‐IR. SEM results showed that the synthesized 4ZnO·B2O3·H2O whiskers' length was about 3–10 μm and the diameter was 0.2–0.3 μm. Further study on the whiskers' growth process and mechanism showed that the formation of the whiskers went through three stages and the morphology of 4ZnO·B2O3·H2O changed from irregular particles to rod‐like structures and finally to whiskers. The variation of the morphology of the 4ZnO·B2O3·H2O whisker with the concentration of the starting material was investigated. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
118.
Nai Fei HU* Hong Yun LIU Li Wen WANG Department of Chemistry Beijing Normal University Beijing 《中国化学快报》2001,(3)
Some synthetic surfactants can form ordered films featuring stacked bilayer by self-assembling. Direct electrochemistry of redox proteins in these biomembrane-like films can provide a good model for the study of redox process in biological system1. Surfactant-polymer composite films possess similar multibilayer structure to surfactant films alone, and have better stability over the latter because of introduction of polymer backbones in the films2-4. In this work, a new type of polyionic comple… 相似文献
119.
Yan Ma Jian Lin Shuang Qin Nai Zhou Qi Bian Hengyong Wei Zhaobin Feng 《Solid State Sciences》2010,12(8):1413-1418
Ag nanocrystals embedded silicate glass was successfully prepared by solid-state field-assisted diffusion, combined with post-annealing process. The changes of glass structure, the chemical states of Ag and O species, the microstructures of Ag nanocrystals, as well as the properties of optical absorption were studied for the as-diffused and post-annealed samples. The result showed that after the field-assisted diffusion process, some Ag+ ions replaced the alkaline ions in the glass matrix. Meanwhile, other Ag+ ions were reduced to Ag0 atoms occupying the interspaces of the network and Ag0 atoms clusters with small size were formed. This caused the relaxation of the glass network and the deceasing of force constant for Si–O linkage. After post-annealing process, bigger size of Ag nanoparticles were formed, which caused the peak corresponding to the surface plasmon resonance (SPR) observed. 相似文献
120.
正交投影列的强收敛准则与广义逆的Galerkin逼近 总被引:1,自引:1,他引:0
对Hilbert空间上的正交投影算子列,给出其强收敛的判别准则.设{Pn}是定义在某个Hilbert空间上的一列正交投影,此准则可描述为:{Pn}是强收敛的,当且仅当{R(Pn)}满足某种适当的条件(见文中的定理2.1),这里{R(Pn)}是与{Pn}相应的值域列.作为上述准则的应用,对有界线性算子,研究其正交广义逆的Galerkin逼近方法;这一研究给出了两条一般性结果(见文中的定理3.1和定理3.2),它们可应用于第一类算子方程的近似求解问题中. 相似文献