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141.
《印度化学会志》2023,100(4):100959
The polymer-ceramic composite electrolytes have great application potential for next-generation solid state lithium batteries, as they have the merits to eliminate the problem of liquid organic electrolytes and enhancing chemical/electrochemical stability. However, polymer-ceramic composite electrolytes show poor ionic conductivity, which greatly hinders their practical applications. In this work, the addition of plasticizer ethylene carbonate (EC) into polymer-ceramic composite electrolyte for lithium batteries effectively promotes the ionic conductivity. A high ionic conductivity can be attained by adding 40 wt% EC to the polyethylene oxide (PEO)/polyvinylidene fluoride (PVDF)-Li7La3Zr2O12 (LLZO) based polymer-ceramic composite electrolytes, which is 2.64 × 10−4 S cm−1 (tested at room temperature). Furthermore, the cell assembled with lithium metal anode, this composite electrolyte, and LiFePO4 cathode can work more than 80 cycles at room temperature (tested at 0.2 C). The battery delivers a high reversible specific capacity after 89 cycles, which is 119 mAh g−1. 相似文献
142.
The human X chromosome contains a large number of inverted repeat DNA palindromes. Although arbitrary substitutions destroyed the inverted repeat structure of MAGEA/CSAG-palindrome during the evolutionary process of the primates, most of the substitutions are compensatory. Using maximum parsimony, it is demonstrated that the compensatory substitutions are prone to occur between bases with similar structures on the human, chimpanzee and orangutan MAGEA/CSAG-palindromes. Furthermore, it is found that MAGEA/CSAG genes also exist in orangutan and rhesus monkey palindromes by homologous searching. This suggests that the MAGEA/CSAG-palindrome might predate the divergence of human and other primate lineages. Comparative sequence analysis of the arms and genes on the primate MAGEA/CSAG-palindromes provides possible evidence of subsequently arm to arm gene conversion. These compensatory substitutions on the MAGEA/CSAG-palindrome of the primate X chromosomes play an important role in maintaining their structural symmetry during the process of formation. 相似文献
143.
Guojian Li Fuyong Xu Aning Ma Yinqin Cheng 《International Journal of Infrared and Millimeter Waves》2007,28(9):725-732
A new kind of V-ridge waveguide is presented in this paper. The transmission problem is solved by edge element for the first
time. The field patterns of the waveguide with single, double and triple V-ridge for different values of dielectric constant
have been presented. Variations of the cutoff wavelength, single-mode bandwidth with the ridge dimensions for different values
of dielectric constant are investigated in detail. The results will be of practical significance in designing ridge waveguide
components in microwave and millimeter wave engineering. 相似文献
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145.
利用临界点理论研究带阻尼项的二阶Hamilton系统周期解的存在性.在具有部分周期位势和线性增长非线性项时,根据广义鞍点定理定理,得到了系统多重周期解存在的充分条件. 相似文献
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合成了2种新型锌卟啉并与金属Mn构建配位聚合物(CPsx,x=1,2)。2种配位聚合物与锚定卟啉(ZnPA)通过金属-配体轴向配位自组装染料敏化太阳能电池(DSSC)。测试结果表明自组装电池具有较好的光电转换效率,特别是基于CPs2的装置具有较高的短路电流和转换效率。我们还对其光学、电化学及光电性能进行了研究,并通过透射电镜(TEM)对自组装体有效敏化在TiO_2电极上进行验证。 相似文献
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