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1.
分析了控制冷却技术对中厚板性能的影响,介绍了几种常用控冷方式的特点、国内各厂家对控冷方式的选择、以及安钢炉卷轧机应用控冷技术后所取得的效果. 相似文献
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The flame‐retardant and smoke‐suppressant properties of inorganic tin compounds such as zinc hydroxystannate (ZHS) and zinc stannate (ZS) were investigated in a comparison with alumina trihydrate, magnesium hydroxide, and Sb2O3 through the limiting oxygen index test and smoke density test. The flame‐retardant mechanisms were studied through the char yield test, SEM, quantitative analysis, thermogravimetry and differential thermal analysis. The thermal degradation in air of flexible PVC treated with the above compounds was studied by thermal analysis from ambient temperature to 800°C. The results showed that tin compounds such as ZHS and ZS could be used as a highly effective flame retardant for flexible PVC, and it appears that the tin compound may exert its action in both the condensed and vapor phases, but mainly in condensed phases as a Lewis acid. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1469–1475, 2005 相似文献
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宋子健 《武汉理工大学学报(材料科学英文版)》2014,29(2):329-333
The applicability of the rapid iodide migration test was systematically studied. Comparative experimental tests of different test conditions, including several external voltages, test durations, concrete ages and mixing proportions, were carried out to make clear the transport behaviors of iodide under parallel electric fields. Numerical simulations were also done using the finite element method to found the correlation between chloride and iodide transport behaviors. The test and numerical results show that the chloride transport behaviors of RIM and RCM tests have a good correlation under the several conditions used in the present paper. Moreover, the influence of external conditions (external voltages, test durations) on the test results is small. Thus, it can be concluded that the RIM method is available to determine the chloride penetration resistance of the chloride-eroded structural concrete. 相似文献
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Upflow anaerobic sludge bed reactors fed on glucose were used to investigate the effects of Ce(3+) on soluble microbial products (SMP) production, which is the majority of the residual chemical oxygen demand present in the effluent. It was found that Ce(3+) concentration of 0.05 mg/L had no significant effect on the amount of SMP production, whereas that of 1 mg/L led to the increase in SMP production. The molecular-weight distribution and carbohydrate analysis indicated that an increase in SMP production may be partly attributed to the release of extracellular polymeric substances (EPS) into the bulk solution resulted from cerium toxicity, and the nucleic acids analysis suggested that increased cell lysis also contributed to SMP accumulation in the presence of Ce(3+). The increase in SMP production in the presence of Ce(3+) is possibly a consequence of the release of EPS and increased cell lysis due to cerium toxicity. 相似文献
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地下管线被视为城市的生命线。分析了地下管线定位仪的基本原理,并在此基础上详细介绍了基于ATmega 128单片机的数字化地下管线定位仪的硬件实现和软件实现,重点分析了基于磁保持继电器的分时供电电源电路。ATmega 128单片机实现了地下管线定位仪的数字化,使得定位仪能快速、准确地对地下管线进行水平定位和垂直定深。 相似文献
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Design of a 2-DOF-PID controller using an improved sine–cosine algorithm for load frequency control of a three-area system with nonlinearities 下载免费PDF全文
This paper proposes an improved sine–cosine algorithm (ISCA) based 2-DOF-PID controller for load frequency control. A three-area test system is built for study, while some physical constraints (nonlinearities) are considered for the investigation of a realistic power system. The proposed method is used as the parameter optimizer of the LFC controller in different scenarios. The 2-DOF-PID controllers are used because of their capability of fast disturbance rejection without significant increase of overshoot in set-point tracking. The 2-DOF-PID controllers’ efficacy is observed by examining the responses with the outcomes obtained with PID and FOPID controllers. The simulation results with the suggested scheme are correlated with some of the existing algorithms, such as SCA, SSA, ALO, and PSO in three different scenarios, i.e., a disturbance in two areas, in three areas, and in the presence of physical constraints. In addition, the study is extended to a four-area power system. Statistical analysis is performed using the Wilcoxon Sign Rank Test (WSRT) on 20 independent runs. This confirms the supremacy of the proposed method. 相似文献
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With the development of nuclear energy, how todispose of the nuclear wastes especially high level liq uid wastes (HLLW) is the world′s subject. One strat egy for reducing the main long term hazard of radioac tive waste is to separate actinides from high level liq uid waste (HLLW) and transmute them into short lived or stable nuclides by nuclear reactions in nuclearreactors or accelerator driven transmutation systems.For this subject, many countries have brought forwardmany p… 相似文献
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贾年 《西华大学学报(自然科学版)》2004,23(3):51-53
现在,关于移动Agent的理论和技术应用正变得越来越广泛。本文作者介绍了移动Agent系统的体系结构和特性,以及需要解决的主要问题,目前的发展状况和研究热点,发展方向及应用前景。 相似文献
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