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591.
Nae-Lih Wu Yu-Ting Weng Fu-Sheng Li Nai-Hsuan Yang Chin-Lung Kuo Dong-Sheng Li 《自然科学进展(英文版)》2015,25(6):563-571
During the operation of Li-ion batteries(LIBs),solvent and electrolyte decomposition takes place at the electrode surface to form a so-called solid-electrode interphase(SEI) passivating-layer.The physical structure and chemical composition of the SEI exert profound effects on various aspects of the electrode performance of the batteries.A new concept of forming polymeric artificial SEIs(A-SEIs) based on rational design of multifunctional polymer-blend coating to achieve favorable electrode/A-SEI/electrolyte interfacial properties is described.Three examples using binary and ternary polymer blends to form mechanically robust and highly Li-ion permeable surface coatings with selected functionalities in the cases of graphite and silicon–graphite composite electrodes have demonstrated greatly enhanced capacity,rate and cycle performance.Given the rich chemistry available from polymer blends,this surface preconditioning approach holds great promise for improving the performance of various negative electrodes to meet the requirements for advanced LIBs. 相似文献
592.
Viral pathogens have threatened human being's health for a long time, from periodically breakout flu epidemics to recent rising Ebola virus disease. Herein, we report a new application of nonstoichiometric Perovskite-type LaxMn O3(x ? 1, 0.95, and 0.9) compounds in spontaneous and continuous disinfection of viruses. Perovskite-type LaxMn O3(x ? 1, 0.95, and 0.9) is well-known for their catalytic properties involving oxidization reactions, which are usually utilized as electrodes in fuel cells. By utilizing superb oxidative ability of LaxMn O3(x ? 1, 0.95, and 0.9),amino acid residues in viral envelope proteins are oxidized, thus envelope proteins are denatured and infectivity of the virus is neutralized. It is of great importance that this process does not require external energy sources like light or heat. The A/PR/8/34H1N1 influenza A virus(PR8) was employed as the sample virus in our demonstration, and high-throughput disinfections were observed. The efficiency of disinfection was correlated to oxidative ability of LaxMn O3(x ? 1, 0.95, and 0.9) by EPR and H2-TPR results that La0.9Mn O3 had the highest oxidative ability and correspondingly gave out the best disinfecting results within three nonstoichiometric compounds. Moreover, denaturation of hemagglutinin and neuraminidase, the two key envelope proteins of influenza A viruses, was demonstrated by HA unit assay with chicken red blood cells and NA fluorescence assay, respectively. This unique disinfecting application of La0.9Mn O3 is considered as a great make up to current sterilizing methods especially to photocatalyst based disinfectants and can be widely applied to cut-off spread routes of viruses, either viral aerosol or contaminated fluid, and help in controlling the possibly upcoming epidemics like flus and hemorrhagic fever. 相似文献
593.
翁莉娟 《北京工商大学学报(自然科学版)》1991,(2)
一个复杂的机械系统,在运行一定时间后进入磨损状态,使失效率增大.为此,考虑系统的寿命分布有两个状态,导出指数——威布尔磨损寿命分布.本文讨论了分布的性质,并推导出一种Bayes自适应方法来估计转折点,给出了递推公式以确定发生转折后的后验概率及其Bayes估计量. 相似文献
594.
具偏差变元的n阶微分方程共轭边值问题的多解性 总被引:1,自引:1,他引:1
研究一类具偏差变元的(k,n-k)共轭边值问题多个正解的存在性,通过把所研究问题转化为相应的全连续算子的不动点问题,利用锥上不动点指数原理和Green函数界的估计,得到了此边值问题存在至少2个正解的两组充分条件.所得结果是没有偏差变元情形下常微分方程边值问题结论的拓广.算例说明所得结果的可应用性. 相似文献
595.
不同氮源对盐生杜氏藻生长和β-胡萝卜素积累的影响 总被引:11,自引:0,他引:11
研究了 Na N O3、 N H4 Cl和脲 3 种不同氮源对盐生杜氏藻生长和 β胡萝卜素积累的影响.结果显示,在0.05~0.5 g/ L 浓度范围内,较高浓度 Na N O3 对杜氏藻生长有利. N H4 Cl对杜氏藻的生长有毒害作用,0.2 g/ L 的浓度即对杜氏藻生长有明显抑制作用,脲在0.1~1.8 g/ L 的浓度范围内对杜氏藻的生长有促进作用.但当脲浓度达到 3.0 g/ L 时,生长速度又有所下降;杜氏藻细胞中β胡萝卜素积累量与培养基中 Na N O3 浓度成反比.在室外强光照下,以 0.1 g/ L 低浓度脲和 Na N O3 作为氮源,杜氏藻细胞均可积累较高的 β胡萝卜素含量.本文的实验结果提示,低浓度脲有利于杜氏藻细胞生长和 β胡萝卜素积累,可作为良好的氮源. 相似文献
596.
本文论述用积分方程法计算复印机磁辊磁场的分布,引入了磁场耦合系数并考虑磁性材料的各向异性,从磁场基本方程出发推导了磁位的积分解式。计算结果与实测的磁场数值符合较好。本文方法可用于磁辊生产中控制加工、装配尺寸误差及材料磁性离散度等影响质量的因素。 相似文献
597.
针对全球导航卫星系统运算量急剧增加的问题,提出一种BDS/GPS双系统快速选星算法.该算法以最佳星座配置法和底座中心法为基础,针对多系统的特点制定选星策略,并对算法进行实验验证.实验结果表明,该算法在保证定位精度基础上有效减少了定位解算的运算量. 相似文献
598.
Sequence and analysis of rice chromosome 4 总被引:1,自引:0,他引:1
Feng Q Zhang Y Hao P Wang S Fu G Huang Y Li Y Zhu J Liu Y Hu X Jia P Zhang Y Zhao Q Ying K Yu S Tang Y Weng Q Zhang L Lu Y Mu J Lu Y Zhang LS Yu Z Fan D Liu X Lu T Li C Wu Y Sun T Lei H Li T Hu H Guan J Wu M Zhang R Zhou B Chen Z Chen L Jin Z Wang R Yin H Cai Z Ren S Lv G Gu W Zhu G Tu Y Jia J Zhang Y Chen J Kang H Chen X Shao C Sun Y Hu Q Zhang X Zhang W Wang L Ding C Sheng H Gu J Chen S Ni L Zhu F Chen W Lan L Lai Y Cheng Z Gu M Jiang J Li J Hong G Xue Y Han B 《Nature》2002,420(6913):316-320
Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O. sativa, one of the first two rice chromosomes to be sequenced completely. The finished sequence spans 34.6 Mb and represents 97.3% of the chromosome. In addition, we report the longest known sequence for a plant centromere, a completely sequenced contig of 1.16 Mb corresponding to the centromeric region of chromosome 4. We predict 4,658 protein coding genes and 70 transfer RNA genes. A total of 1,681 predicted genes match available unique rice expressed sequence tags. Transposable elements have a pronounced bias towards the euchromatic regions, indicating a close correlation of their distributions to genes along the chromosome. Comparative genome analysis between cultivated rice subspecies shows that there is an overall syntenic relationship between the chromosomes and divergence at the level of single-nucleotide polymorphisms and insertions and deletions. By contrast, there is little conservation in gene order between rice and Arabidopsis. 相似文献
599.
首先介绍啤酒发酵工艺过程中温度的控制原理,接着说明系统的基本功能以及硬件结构,最后介绍系统的软件设计,着重介绍应用软件中各模块的基本功能。 相似文献
600.
水环境容量计算方法研究 总被引:18,自引:0,他引:18