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951.
以围护结构的耗热量指标、传热系数限值和门窗空气渗透耗热量为重点,对严寒地区居住建筑实施节能65%进行了分析,提出围护结构各部分的传热系数限值.对围护结构如何实现节能65%的要求,从围护结构构造和技术角度进行了讨论;并阐述降低门窗部位的空气渗透耗热量是下一步节能的关键. 相似文献
952.
XU Xing-Ling TANG Zong-Xun GUO Zhi-Zheng CHEN Yun-ShengDepartment of Chemistry Northwest University Xi''''an Shanxi ChinaSHI Ni-Cheng MA Zhe-Sheng China University of Geoscience Beijin ChinaHAN Yu-Zhen Department of Chemistry Beijin University Beijin China 《中国化学》1995,(1)
Based on the phase equilibrium study of the system Sm(ClO4)3-4-monochloroace-tylantipyrine (C13H13ClN2O2)-H2O at 30℃, we have synthesized the title complex [Sm(C13H13Cl. N2O2)3(H2O)4](C1O4)3.4H2O. The single crystal structure analysis on RASA-IIS Rigaku diffrac-tometer shows that the coordination number of the metal ion is nine and the geometry of the complex is tricapped trigonal prism. Two of the three molecules of organic ligand act as bidentate chelated through both carbonyl oxygens to the metal ion, but the other one as a monodentate coordinated only through the ring carbonyl oxygen, the side chain carbonyl is far away from the central ion. The crystal is monoclinic, space group P21, a = 18.013(4), 6 = 14.709(3), c = 10.536(3) A, β=94.69(2)°, V=2782(1) A3, Z=2. 相似文献
953.
中国古代趣味物理实验十摘 总被引:1,自引:0,他引:1
从中国若干典籍中采撷了10个趣味性较浓的物理实验。这些实验构思奇特,设计巧妙,且大多可用于课堂演示,对了解中国古代物理实验发展的历程具有一定参考价值。 相似文献
954.
WANG Jingping LI Zhixia ZHANG Gencheng FEI Zhenghao TANG Shuhe Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources Environmental Protection Yancheng China The department of Yancheng Teachers College Yancheng China 《Chinese Journal of Reactive Polymers》2006,(2)
1. INTRODUCTION Chlorophenolic compounds are very toxic, and many are known or suspected human carcinogens. They have been widely used for many industrial purposes. The removals of chlorophenols are of high industrial and environmental interest [1~2]. The adsorption resin is another adsorbent widely employed for isolation and purification of organic substances, treatment of wastewaters, solid phase extraction, and so on. A variety of materials has been developed and tested, such as Amber… 相似文献
955.
Behaviour of Self-Standing CVD Diamond Film with Different Dominant Crystalline Surfaces in Thermal-Iron Plate Polishing 下载免费PDF全文
Self-standing CVD diamond films with different dominant crystalline surfaces are polished by the thermal-iron plate polishing method. The influence of the dominant crystalline surfaces on polishing etfficiency is investigated by measuring the removal rate and final roughness. The smallest rms roughness of 0.14 μm is measured with smallest removal rate in the films with the initial (220) dominant crystalline surface. Activation energy for the polishing is analysed by the Arrhenius relation. It is found that the values are 170kJ/mol, 222kJ/mol and 214kJ/mol for the film with three different dominant crystalline surfaces. Based on these values, the polishing cause is regarded as the graphitization-controlling process. In the experiment, we find that transformation of the dominant crystalline surfaces from (111) to (220) always appears in the polishing process when we polish the (111) dominant surface. 相似文献
956.
研究了测度链上的柯西不等式,给出测度链上柯西不等式的具体形式.此外,还对测度链上的柯西不等式作了推广. 相似文献
957.
A method for investigating the azimuthal correlations between directed and elliptic flow in heavy ion collisions is described.The transverse anisotropy of particle emission at AGS energies is investigated within the RQMD model.It is found that the azimuthal correlations between directed and elliptic flow are sensitive to the incident energy and impact parameter.The fluctuations in the initial stage and dynamical evolution of heavy ion collisions are not negligible. 相似文献
958.
利用夏普里值来识别导致顾客不满意的质量属性.因为夏普里值差异很小的质量属性具有高度的相关性,所以可以把具有相同或者类似的夏普里值的质量属性划分为同类属性,从而能够识别导致顾客不满意的质量属性.算例进一步验证该方法的可行性和正确性. 相似文献
959.
960.