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991.
LA Xiao- shuai ZHANG Zhen- feng CHEN Shu- jun LIU Xiao- jie LI Fu- min L�� Qing 《钢铁研究学报》2015,27(7):20-25
高炉冶炼钒钛矿时炉缸会产生大量的沉积物,影响高炉正常生产。对炉缸沉积物进行了检测,对高炉渣的冶金性能进行了试验研究,结果表明:沉积物的成分复杂,其中一些沉积物的铝、硅含量较大;沉积物形成的主要来源为TiC包裹金属铁的沉降聚集,渣铁对耐火材料的侵蚀,含高熔点物质的高黏度炉渣在炉底堆积。高铝中钛渣的黏度过大,炉渣碳含量较高是导致沉积物形成的主要原因,因此,改善高铝中钛渣的冶金性能可以有效抑制沉积物的形成。 相似文献
992.
《Egyptian Journal of Petroleum》2015,24(4):493-503
Here in, cationic surfactants namely (1-octyl, decyl, and dodecyl-4-mercaptopyridine-1-ium bromide) I, II and III, respectively, were synthesized. The inhibition effect of these surfactants on the corrosion of carbon steel in 1 M HCl was studied by polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. Polarization curves revealed that the used inhibitors represent mixed-type inhibitors. Adsorption of used inhibitors led to a reduction in the double layer capacitance and an increase in the charge transfer resistance. Adsorption of used compounds was found to obey Langmuir isotherm. 相似文献
993.
994.
995.
Khomgris ChaiyoPhadungsak Rattanadecho Somchart Chantasiriwan 《International Communications in Heat and Mass Transfer》2011,38(2):249-254
The problem of seepage flow through a dam is free boundary problem that is more conveniently solved by a meshless method than a mesh-based method such as finite element method (FEM) and finite difference method (FDM). This paper presents method of fundamental solutions, which is one kind of meshless methods, to solve a dam problem using the fundamental solution to the Laplace's equation. Solutions on free boundary are determined by iteration and cubic spline interpolation. The numerical solutions then are compared with the boundary element method (BEM), FDM and FEM to display the performance of present method. 相似文献
996.
997.
The present study introduces the expression of the radiative source term in an absorbing and emitting medium, which is caused by the collimated incidence of radiation on boundary surfaces. Three different optical characteristics of the boundary surfaces are considered: (1) both opaque, (2) both semitransparent, and (3) one opaque and the other semitransparent. The study conducted numerical simulation for the excess temperature responses at the incident surface and the nonincident one of a semitransparent medium, which is irradiated by a short‐time laser pulse. The variables affecting the temperature response include the wavelength of the irradiating laser pulse, the spectral properties of the medium, the optical characteristics of the boundary surfaces, a reference temperature, and a thermal diffusivity. The results show that considerable deviations may be produced if the Planck or Rosseland mean‐absorption coefficient is employed to treat a nongray medium. Thus, it is suggested that spectral band models be used. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(5): 331–343, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10040 相似文献
998.
A micro‐CT scanner was employed to investigate inner characteristics of porous media, and particular cakes were taken as samples. By obtaining the inner pore structure and inner structure reconstruction, porosity and its variation in the samples, water distribution in pores, and other inner characteristics were determined and explored. When the sample was dried after immersion in water, the solid frame shrank, some pores became larger and the porosity increased, while the sample not immersed in water did not change much after being dried. The experiments indicate that micro‐CT scanning is an effective technology to study the inner structure of porous materials with pores larger than tens of microns and also can be used to explore some important transport performance. ©2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(4): 208– 214, 2007; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/htj.20155 Copyright © 2004 Wiley Periodicals, Inc. 相似文献
999.
1000.
李智丽 《理化检验(物理分册)》2011,(1):53-56
通过低倍检验、金相检验和断口分析等方法分析了Q345E热轧中厚板探伤不合格的原因。结果表明:探伤不合格的原因是在热轧板中心区域偏析带存在硫化锰和碳氮化铌夹杂物,并通过控制和调整工艺解决了该问题。 相似文献