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501.
结合MCAI课件的优点,依据教学设计的原理,文中介绍了结构化学电子教案的开发平台、制作过程、总体结构和使用特点。 相似文献
502.
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
503.
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
504.
为深入了解混凝土收缩徐变对钢-混凝土组合梁力学性能的影响,采用随时间变化的换算弹性模量法建立了钢-混凝土组合梁混凝土收缩徐变的增量微分模型,得到了组合梁内力、挠度和钢-混凝土界面滑移的微分控制方程.根据边界条件,给出了内力、变形及钢-混凝土界面滑移等各项力学性能指标的闭合解.为验证增量微分方法的正确性,对试验梁和算例梁进行了跨中挠度-时间曲线、沿梁高应变分布及梁端钢-混凝土界面滑移的计算分析.计算结果表明,所建立的增量微分法与试验值和其他计算方法的计算结果吻合较好,可以有效地预测钢-混凝土组合梁的长期力学性能. 相似文献
505.
506.
苍岭隧道1号通风竖井施工技术 总被引:1,自引:0,他引:1
文章介绍了苍岭隧道1号竖井施工技术方案的设计与施工实践、竖井开挖、提升设备的选型、二次衬砌的施工工艺以及相关的安全措施. 相似文献
507.
本文应用有限元素法求解二维肋片传热问题,为了进行比较,又应用解析法求解一维肋片传热问题,分别得到了沿肋片长度方向上的温度分布曲线,最后将这两种传热模型的结果进行了分析比较,从而得出一维和二维肋片传热模型的适用条件。 相似文献
508.
三维槽道两相湍流的大涡模拟 总被引:1,自引:0,他引:1
利用基于动态粘性亚网格模型的大涡模拟方法,分别模拟计算了Ret=180的三维槽道湍流内的三种颗粒的运动状况.统计得到的流体的平均速度、脉动速度等结果与有关文献中的DNS结果一致,不同的颗粒在流场中(特别是近壁区)表现出不同的行为,并再现了颗粒在壁面附近局部富集的现象. 相似文献
509.
Natural variation in Ghd7 is an important regulator of heading date and yield potential in rice 总被引:22,自引:0,他引:22
Xue W Xing Y Weng X Zhao Y Tang W Wang L Zhou H Yu S Xu C Li X Zhang Q 《Nature genetics》2008,40(6):761-767
Yield potential, plant height and heading date are three classes of traits that determine the productivity of many crop plants. Here we show that the quantitative trait locus (QTL) Ghd7, isolated from an elite rice hybrid and encoding a CCT domain protein, has major effects on an array of traits in rice, including number of grains per panicle, plant height and heading date. Enhanced expression of Ghd7 under long-day conditions delays heading and increases plant height and panicle size. Natural mutants with reduced function enable rice to be cultivated in temperate and cooler regions. Thus, Ghd7 has played crucial roles for increasing productivity and adaptability of rice globally. 相似文献
510.
基于随机优化的工程稳健设计 总被引:10,自引:3,他引:7
根据影响产品质量的因素,讨论了质量设计的准则和设计解的稳健性,并利用随机建模原理提出一种工程稳健设计的新方法。该方法与一般稳健设计不同的是,通过同时调整设计参数与控制其容差来达到稳健设计的最优解。数值分析表明,该方法是十分有效的。 相似文献