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111.
112.
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
113.
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
114.
Guo Ya-kun Wen Xian-yun Institute of Hydraulic Research Chengdu University of Science Technology Chengdu P.R.China 《水动力学研究与进展(B辑)》1993,(1)
In this paper,using complex functional theory,the authors turn the potentialflow around the surface irregularities in a pressure conduit and semi-infinite platforms intoDirichlet problem.Based on Schwarz formula and by the application of Plemelj's formula,theauthors change the problem into the integration of a Cauchy boundary integral equation in theflow plane through the substitution of variables.Using numerical integration,the authors obtainthe velocity distribution and pressure coefficient along surface irregularities and platforms.Thephysical concept of this method is clear,the convergent speed is rapid and the computative effi-ciency is high.The calculated values agree well with the measured results.It is an effective andsimple method in solving potential flow. 相似文献
115.
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
116.
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
117.
118.
119.
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
120.
In this paper we propose a new method to extract the vortices, sources, and sinks from the dense motion field preliminary estimated between two images of a fluid video. This problem is essential in meteorology for instance to identify and track depressions or convective clouds in satellite images. The knowledge of such points allows in addition a compact representation of the flow which is very useful in both experimental and theoretical fluid mechanics. The method we propose here is based on an analytic representation of the flow. This approach has the advantage of being robust, simple, fast and requires few parameters. 相似文献