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71.
国内核电厂吸取福岛事故的经验教训,增加了严重事故后应急补水设施,完善了应急补水的相关功能,进一步提高了核电厂的安全水平.对M 310核电机组严重事故状态下的应急补水设施进行技术分析,分析计算结果表明,应急水源到应急补水泵接入点距离过长,水损过大,实际补水压力及流量无法满足设计要求.针对该问题提出一系列设计改进措施,优化改进后的应急补水设施可保证严重事故工况下M 310核电机组应急补水设施的可用性,从而进一步提高核电机组的安全性. 相似文献
73.
ZENG Yanping ZHANG Maicang DONG Jianxin ZHANG Lina XIE Xishan 《稀有金属(英文版)》2005,24(3):298-300
1 IntroductionRecently the key components in advanced aircraftengines are widely made of nickel-base P/M super-alloy. However, non-metallic inclusions are intro-duced into this material during powder metallurgyprocessing. In industry, although many method… 相似文献
74.
Preparation and electrochemical performance of nanosized Co3O4 via hydrothermal method 总被引:1,自引:0,他引:1
The hydrotalcite-type cobalt compounds were prepared through oxidation of Co(OH)2 gel using NH4OH as precipitating agent and H2O2 as oxidant. These hydrotalcite-type cobalt compounds were transformed into Co3O4 through hydrothermal decomposition with nanostructural deformation. The precursor and product were characterized by Fourier-transform infrared(FT-IR) spectrum, X-ray diffractometry(XRD) and transmission electron microscopy(TEM). The electrochemical performances of as-prepared nanosized Co3O4 as anode materials in lithium-ion batteries were tested by charge-discharge test in the voltage range of 0-3.0 V. The influence of morphology of Co3O4 particle on the capacity and cycling performance was studied. The results show that the shape and size of the final product can be controlled by altering cobalt sources. The irregular cubic Co3O4 with the average particle size of about 10 nm shows the best electrochemical performance. After 10 charge-discharge cycles, the specific charge capacity retains 555 mA.h/g. 相似文献
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Polyaniline/Attapugite/PE(PAn-ATTP/PE)composites containing particles with core-shell structure were obtained via the two-step blending processs. The experimental condition is as follows: Organo-attapulgite and PAn was obtained by modifying attapulgite with laury benzenesulfonic acid sodium salt and, then added to PE. The electrical conductivity, structure and properties of the composites were studied. Under the function of shear stress, core-shell structure particles with ATTP as the core and PAn as the shell were formed in the composites. The structure of PAn-ATTP/PE composites were characterized by FTIR,XRD,SEM, etc, respectively. The effects of concentration of doping agent on the conductivity and mechanical property of the composites were investigated. The mechanical properties and impact fracture surface of the ternary composites were studied by means of the tensile tester, SEM, etc. The results show that polyaniline encapsulated ATTP enhances the strength of the PE. And the conductivity of PAn-ATTP/PE composites of is improved effectively when polyaniline encapsulated ATTP is added. The composite have good conductivity when 10% polyaniline encapsulated ATTP is added. 相似文献
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介绍了带钢热连轧过程中电动活套和液压活套各自的张力控制模型,前者以电机电流作为控制对象,后者以液压缸压力作为控制对象。 相似文献
80.
1 INTRODUCTION Mass transfer across free interface of gas-liquid flow is of extensive importance and is encountered in most industrial applications. A close investigation of concentration distribution near the interface is helpful to understand mass transfer phenomena, to guide the development of transport theories, and to optimize the design of gas-liquid contact equipment. Laser holographic interference technique provides a precise and noncontact measurement method for measuring the tran… 相似文献