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41.
列出了2000年以来发布的部分供暖供热、空调制冷、节能、通风除尘、洁净技术、计算机及网络技术、防火排烟、给水排水、减振降噪、环境保护、室内空气品质、材料与设备等标准.以及有关设计、验收规范和一些综合类标准。 相似文献
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Shaojie Xu Yong He Biyi Huang Yanwei Zhang Zhihua Wang Kefa Cen 《International Journal of Hydrogen Energy》2018,43(7):3597-3604
Although several technologies, such as reactive distillation and catalytic membrane reactor, have been proposed to improve HI conversion efficiency, they still experience several challenges for the application in HI section. In this study, an electrochemical cell was employed for hydriodic acid decomposition under the presence of iodine. Several commercial proton-exchange membranes (PEMs), namely, Nafion 117 and Nafion 115, were used as separators for the electrochemical cell. Anodization of iodide anion occurred at the graphite electrode in the anode compartment. Hydrogen was generated by the reduction reaction of hydrogen cations, which migrated from anolyte to catholyte. In electrolysis experiments, PEM showed good performance in terms of high transport number of proton and low iodine permeation. Several parameters, such as operating temperature, HI molarity, and I2 molarity in anolyte, which affected current efficiency, iodine permeance, and electric resistance of test cell, were investigated. High operating temperature and I2 molarity in anolyte enhanced the permeability of iodine, which had several negative influences on electrochemical cell performance. Although current efficiency was negatively affected by increasing temperature and I2 molarity, it still remained above 0.85 in the range of 30 °C–75 °C. Ohmic resistance, which is a component of cell resistance, offered by PEM was investigated with Nafion 117 and 115. Apart from graphite plates, activated carbon papers were adopted as electrodes to reduce the overpotentials due to their high specific surface characteristic. 相似文献
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Carbonization experiments were conducted on four kinds of sub‐bituminous coal particles at a temperature range of 450–1200 °C. The effect of treating temperature on the grindability of produced carbonaceous materials was investigated, and its mechanism was analyzed through various means. Results show that the grindability of all coals, whether caking or slightly‐caking, exhibit the same variation trend with an increase in carbonization temperature. Moreover, the entire process can be divided into four stages. (1) After the most intense devolatilization stage, the grindability of carbonaceous material exhibited different degrees of increase compared with that of raw coal because of the development of a pore structure. (2) The first significant decrease in the grindability occurred from the plastic stage to the complete resolidification of the coal matrix. (3) After the aromatic polycondensation stage accompanied by a large amount of H2 release, the coal molecular structure became compact, such that the grindability of semi‐coke considerably decreased again. (4) At high temperatures, the coal matrix underwent graphitization, which changed semi‐coke to coke. The molecular structure of coal became ordered, and the grindability decreased again. The analysis shows that a change in the internal chemical structure of carbonaceous material has a much more pronounced effect on grindability than a change in its pore structure, except in the first stage. The constant compaction and regularization of the coal molecular structure continued happening throughout the entire process and play a decisive role in the change in grindability. 相似文献
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中条山胡—蓖型铜矿床成因新认识 总被引:1,自引:0,他引:1
讨论了剥离断层与成矿物质来源,矿体空间分布型式以及矿化特征等方面联系,从而提出胡-蓖型铜矿床是一个受剥离断层控制的“热液型(断)层状矿床”。 相似文献
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以钛酸四丁酯与醋酸钡为钛酸钡前驱体,PEG为分散剂,硝酸钐为掺杂物种给体,采用溶胶-凝胶法制备改性的Sm掺杂BaTiO3纳米粉体。样品经X射线衍射(XRD)与差热-热重联用(DSC-TGA)的方法对其进行了表征。研究了煅烧温度与分散剂对BaTiO3粉体粒径与相的影响。结果表明:立方相在700~850℃生成,前驱体经950℃热处理制得后呈四方相BaTiO3。分散剂PEG可抑制BaTiO3晶粒增长;随煅烧温度升高,粉体粒径增大。适量Sm掺杂可以抑制杂质BaCO3相的形成。 相似文献
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