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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
981.
锰硅合金生产中入炉锰矿的优化搭配 总被引:1,自引:1,他引:0
通过对以往配矿思路的缺陷分析,引入炉料含锰的概念和与配方思路,相应补充和推导部分配矿参数,浅谈了这些参数的应用方法及步骤,以达到合理与矿和优化配化的目的及效果。 相似文献
982.
983.
本文通过实验,利用微机在线测量系统对旋涡流化床悬浮空间颗粒浓度场进行了测试和分析,得出了有利于稳定燃烧的几点结论。 相似文献
984.
Georg Koschek 《Journal of microscopy》1992,168(1):79-84
The suitability of cathodoluminescence (CL) measurements for differentiating between different paint pigments is demonstrated with an example of a combined energy-dispersive X-ray (EDX) and CL analysis of different zinc oxide (ZnO) pigments in a paint fragment where the EDX spectra are virtually identical, but where the CL spectra show significant differences. Consequently, it is possible to distinguish different pigments on the basis of CL spectra and monochromatic CL micrographs. 相似文献
985.
Guillermo R. Villalobos Shyam S. Bayya Jasbinder S. Sanghera Robert E. Miklos Frederic Kung Ishwar D. Aggarwal 《Journal of the American Ceramic Society》2002,85(8):2128-2130
A spray drying approach was used to apply 15-nm-thick SiO2 continuous coatings onto ZnS:Ag phosphor particles. A prehydrolyzed TEOS dip coating formula was used as the SiO2 precursor. The phosphor was mixed together with the precursor then atomized without allowing gelation to occur until the droplets containing the particles were in flight. The coating gelled and dried while falling through a graded heat zone. The dried coated particles were captured in a cyclone separator and heat-treated to further densify the SiO2 coating. The coatings protected the phosphors while in service in field emission display (FED) devices. 相似文献
986.
S. H. Lin 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1991,51(4):473-482
A physical model is given in the present report for representing a three-phase biological fluidized bed reaction system which consists of microorganism-coated particles, waste water and air. The system is assumed to be well fluidized. The physical model can be represented by two differential equations describing, respectively, the substrate axial dispersion and diffusion/reaction. Numerical values of the physical parameters are selected from the literature or estimated from semi-empirical equations. The governing system equations are solved by an iterative finite-difference scheme. The theoretical predictions are compared with several experimental measurements and the agreement between them found to be very good, validating the physical model reported here. 相似文献
987.
988.
989.
990.
Jaroslav Stejskal Pavel Kratochvíl Josef Urban G. S. Kapur Y. Lakshminarayana 《Polymer International》1993,30(1):81-87
Methyl methacrylate was polymerized in an aqueous medium in the presence of gelatin using potassium persulfate as initiator. The dispersion mode of polymerization, when the monomer is completely miscible with water, was investigated and compared with an emulsion process, which proceeds at higher monomer concentration. Spherical and relatively uniform polymer particles were formed. Macroscopic precipitation of polymer is prevented by combination of the steric stabilization by grafted gelatin and of repulsive electrostatic interactions from the initiator residues attached to the particle surface. Static and dynamic light scattering have been used to determine the molar mass (molar mass of the whole dispersion particle, MwD ~ 108-109 g mol?1) and hydrodynamic radius (RhD ~ 50-120 nm) of the particles. The number of particles per unit volume does not depend on overall monomer concentration, and it is higher, and therefore the particle size is smaller, than that observed for the soapless emulsion polymerization. The addition of gelatin may be thus used to modify the particle size. Acrylonitrile dispersions were prepared under similar conditions. Unlike methyl methacrylate, this monomer does not swell the polymer particles. While poly(methyl methacrylate) particles are spherical and relatively uniform, the polyacrylonitrile dispersions consist of polydisperse aggregates of tiny polymer particles. 相似文献