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101.
碳化硅加热元件的电性能和使用 总被引:2,自引:0,他引:2
本文介绍碳化硅加热元件的电特性、表面负荷以及工作气氛对它的影响,并对它设计和使用要点举例予以说明。 相似文献
102.
103.
桑帅 《有色冶金设计与研究》2006,27(3):33-35
浅议多层住宅砖混房屋中构造柱的作用及设置方法;探讨了砖混结构墙下条形基础底面积重复利用问题及其解决方法。 相似文献
104.
M. O. Al-Hunaidi 《Journal of Nondestructive Evaluation》1996,15(2):71-82
The potential of using Spectral analysis of surface waves (SASW) for nondestructive testing of pavement and soil sites has been demonstrated in several publications. The usual SASW field testing and data analysis procedures and the assumption of a single propagation mode yield accurate results when there are no sharp changes in the stiffness of the site with depth. When this is not the case, however, difficulties arise in the interpretation of experimental data due to the participation of more than one mode in the wave field. In an earlier study, the multiple filter/crosscorrelation technique was suggested for analyzing multi-mode SASW signals. This technique, however, may not yield accurate results when propagation modes are closely spaced. A more general method using spectral analysis in the frequency wave-number domain is presented in this paper. Formulas are presented for determining a reasonably small number of surface measurements, and the accuracy of this method in resolving experimental dispersion curves is demonstrated for a pavement site. 相似文献
105.
106.
介绍了用CO_2堆焊35CrMo钢钻井泵阀箱密封面磨损修复工作,通过试验表明,采用Φ1.2mm的H08Mn2Si焊丝,以短路过渡CO_2焊法施焊,可以获得致密、耐磨的堆焊金属层。该法已成功地用于生产,取得了良好的经济效益。 相似文献
107.
108.
Leonardo Setti Pier Giorgio Pifferi Gaetano Lanzarini 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,64(1):41-48
A new mathematical model for n-alkane biodegradation in crude oil, heavy oil and paraffinic mixtures is described. The pattern of n-alkane degradation as a function of the inverse of hydrocarbon chain length reported in this paper can be considered as general behaviour for many aerobic n-alkane biodegradation processes. A new interpretation of n-alkane biodegradation as a function of surface tension, is given. A mathematical expression was obtained starting from the degradation values of n-alkane and relative surface tension, which is a parameter independent of fermentation conditions. An interesting parameter, b, was identified which represented the accelerating conversion factor for n-alkane biodegradation. The findings suggested that the n-alkane biodegradation. The findings suggested that he n-alkane biodegradation rate may be affected by the fermentation condition (agitation, aeration, etc.) and by the strain of microorganism, while the behaviour pattern of n-alkane degradation was essentially linked to the substrate characteristics (molecular structure, molecular weight and density). 相似文献
109.
The evolution of surface defects during shape rolling of high‐speed steel billets is studied using longitudinal surface defects prepared by machining and welding. The reduction of the defects during rolling in a production mill is compared to the total area reduction of the billets. Samples are collected after pass 4, 6, 8, 14, 19 and the final pass, 28, representing the finished 5.5mm wire. By inspecting the cross sections, the rotation of the billets from pass to pass is evaluated. Results from FE simulations on solid billets are compared to the experimental results. Generally, simulations predict less reduction than observed experimentally. In most cases cracks reduce most effectively followed by carbon steel welds and stainless steel welds. 相似文献
110.
A. N. Palagushkin S. A. Prokopenko A. P. Sergeev A. N. Arlamenkov 《Optical Memory & Neural Networks》2007,16(4):288-294
The results of experimental definition of optical parameters of silver nanolayers by the method of surface plasmon resonance
(SPR) are described. The goniometric installation for measurement of angular dependences of reflection of light by layered
nanosructures at the attenuated internal reflection (angular spectrum of reflection) is designed. Calculation of optical parameters
of nanolayers is executed taking into account the form of a curve of tin angular spectrum of reflection.
The text was submitted by the authors in English. 相似文献