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101.
This paper discusses the seafloor thermalwater spout sedimentary activity in South Yongmei Depression according to the following
evidences: the Yongmei region was in an extended tectonic environment of metaplateform and locally developed intracontinental
rift aulacogen in company with the activity of rich alkali, high potassium volcanics of double-peak type. Several kinds of
hydrothermal sedimentary rocks and the ore-bearing sedimentary formations of copper-polymetals, iron and manganese exist in
this region with a zoning feature of the seafloor thermalwater spout sedimentation.
Project supported by the Science Foundation of NECC for Returns
Synopsis of the first author Wu Chengjian, associated professor, born in 1957, majoring in ore deposit and mineralgraphy. 相似文献
102.
Convection promotion within a tubular ceramic membrane by using the kenics static mixer is studied. The experiments were carried out with aqueous solutions of pectin and sodium carboxymethylcellulose (CMC), for Reynolds number in the range of 60-5000. From the results of these experiments it can be concluded that the presence of convection promotor decreasing the concentration of the gel layer. The experimental data are correlated satisfactorily by the equation of the general form Sh=A ReaScb. 相似文献
103.
Rates of coke formation during steam pyrolysis of naphtha have been investigated in a jet-stirred reactor both for sodium silicate coated and uncoated Inconel 600 surfaces in the temperature range of 1078–1108 K. Coke formation rates were significantly reduced on sodium silicate coated plates due to the passivation of the metal surface. However, the coking rates gradually increased with successive decokings of the coated surface. 相似文献
104.
本文简要介绍了国外在开发超酸性气体过程中遇到的材料选择、腐蚀监测、水化物堵塞、超酸性气的处理和加工等问题所采取的措施和办法。 相似文献
105.
106.
107.
黄运平 《武汉理工大学学报(材料科学英文版)》2002,17(1)
The topological index F* is defined and obtained by the method of a non-dimensional unit calculation in which three matrices multiply with each other. These matrices represent the connective cases of atoms in a molecule, the structural features of atoms on top and the bonded cases of the adjacent atoms respectively. The standard formation enthalpies of ABn(g) molecules were correlated with F'* (A = C, Al, Si, Ti, Zr, B = F, Cl, Br, I, H, n=1 -4) and these correlation coefficients are all more than 0.96. Some molecules (e.g CH4, SiH4,etc. )can be preferably handled by F* but can not be dealt with by other topological indices. By contrast to traditional hydrogen suppressed graph, the contribution of hydrogen atoms to structures and properties of molecules is considered. 相似文献
108.
109.
Frederick Bloom 《Chemical engineering science》2003,58(2):353-365
A model for a semi-batch flotation separation process has been developed, based on available microprocess probabilities, and compared to experimental data obtained using a WEMCO laboratory flotation cell. In general, the model predicts the correct experimental trends. In many cases, the model also predicts removal efficiency very well. Parametric studies reveal that the model predictions are sensitive to a stability parameter, the turbulent energy density in the flotation cell, the contact angle between the solid particle and fluid, and the ratio of initial-to-critical film thickness. 相似文献
110.
高含酸性气碳酸盐岩气藏流体敏感性实验研究 总被引:2,自引:0,他引:2
对川东北雷口坡组、嘉陵江组、飞仙关组、长兴组高含H,S及032的碳酸盐岩储层流体敏感性进行了实验研究,结果表明岩样速敏损害弱~强,水敏和盐敏损害中偏弱~极强,碱敏损害严重。岩石学分析揭示,川东北高含酸性气碳酸盐岩储层发育伊利石、微晶石英、白云石、方解石、硫化钙等潜在损害物质。钻井完井液侵入会破坏储层各物质间的原始动态平衡,诱发储层损害。主要损害机理为:①储层流体pH增加引起黏土矿物以及微晶石英失稳;②碱液与微晶石英、长石、白云石反应生成硅酸盐、高岭石、水镁石等新矿相;③流体矿化度改变可降低伊利石微粒间的连接力;④硫化钙水解产生OH^-,过量的OH-与Ca^2+结合形成氢氧化钙沉淀;⑤储层含水饱和度和流体离子浓度改变,致使焦沥青脱附并在储层深部沉积;⑥硬石膏水化膨胀、分散运移。针对该气藏损害机理,可采用屏蔽暂堵技术以形成优质滤饼,有效降低储层流体敏感性损害。图5表2参10。 相似文献