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31.
MOS控制晶闸管的三重扩散工艺研究 总被引:1,自引:0,他引:1
本文对MCT的核心工艺-三重扩散工艺进行了详细研究。通过SUPREM-Ⅲ计算机工艺仿真,获得了三重扩散的工艺条件。 相似文献
32.
Al-Li alloys being developed as lighter, substitutes for conventional high strength Al alloys are to be processed by routine
methods. During extrusion of a 8090 Al-Li alloy, the extrusion die container failed causing some alarm. This failed die container
was analysed to examine if the failure was caused by interaction of Li diffusing out of Al-Li alloy with the carbides of die
steel. The evidence, although not conclusive, is sufficient to exercise caution during such processing. 相似文献
33.
Riley William T.; Schumann Mary F.; Forman-Hoffman Valerie L.; Mihm Patricia; Applegate Bradford W.; Asif Ofer 《Canadian Metallurgical Quarterly》2007,38(1):44
Increased adoption of empirically supported treatments (ESTs) has been hindered in part by inadequate and inconvenient access to EST information and training. To improve diffusion of ESTs, the authors developed a Web application to provide practitioners with concise information by disorder on ESTs. The resulting site, therapyadvisor.com, was evaluated by 239 practicing psychologists to assess the usefulness of the site and explore possible interactions of EST attitudes on ratings of usefulness and impact. Two thirds of participants indicated using ESTs in practice, and limited time and resources were cited as primary barriers to EST adoption. The Web application was rated positively by most participants and was reported to increase awareness of and commitment to try ESTs among approximately 60% of participants. The results of this project support the feasibility of a Web application to increase diffusion and promote further adoption of ESTs. Technological and e-learning advances are promising directions for encouraging the adoption of ESTs specifically and evidence-based practice generally, particularly among busy practitioners who have inadequate time and resources for more traditional forms of dissemination and training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Nourh ne Boudhrioua Bertrand Broyart Catherine Bonazzi Jean-Dominique Daudin 《Drying Technology》2005,23(12):2313-2335
A method is presented for computing the values of apparent diffusivity in solids with respect to the concentration of the diffusing substance (water or sodium chloride). This method does not require any assumption upon the mathematical relationship between diffusivity and concentration. It can be applied to experimental measurements of local concentration versus position within the solid (profiles) with relatively few measurements (circa 10) and a mathematical smoothing of the experimental data by using an artificial neural network model. The method was first validated on simulated data obtained by using a constant diffusivity value and on experimental profiles when the relation between diffusivity and concentration was given. It was then applied to original experimental moisture profiles obtained by putting gelatin gels with different initial moisture contents into contact for up to 14 days. The method was also successfully applied to five sets of experimental moisture and sodium chloride profiles taken from the literature and obtained from different food products. Apparent diffusivities calculated by our method were found in agreement with those obtained by authors using different numerical methods to compute the diffusivity values. 相似文献
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通过高炉鼓风机扩压叶片断裂事故,从化学分析、物理检验,结合使用情况对扩压叶片断裂原因进行了详细分析,并提出了改进措施。 相似文献
38.
Al-Cu双金属复合结构的扩散连接试验研究 总被引:16,自引:0,他引:16
应用扩散连方法进行了Al-Cu双金属复合结构的试验研究,比较了不同的焊接工艺,材料组合以及母材状态情况Al合金与Cu的连接性,观察了接头区域的微观组织结构,研究表明,固相扩散连接是一种适用于异种材料连接的有效方法,通过在连接区域形成Al-Cu金属间化合物,达到Al和Cu的有效连接,材料组合,母材原始状态以及连接工艺参数对Al合金与Cu的扩散连接存在着明显的影响。表面镀Ni工艺不但能够有效阻止Al和Cu之间形成脆性相,而且Al和Ni之间形成了良好的扩散连接,改善了接头性能。 相似文献
39.
The removal of Cu(II) by adsorption on fly ash has been found to be concentration, pH and temperature dependent. The kinetics of adsorption indicates the process to be diffusion controlled. The Langmuir constants have been calculated at different temperatures, and the adsorption has been found to be endothermic (ΔH = 15.652 kcal mol?1). The maximum removal is observed at pH 8.0, and variation in adsorption with pH has been explained on the basis of surface ionisation and complexation. 相似文献
40.
Fan Jing yu Wang Dao zeng Zhong Bao chang Shanghai Institute of Applied Mathematics Mechanics Shanghai University Shanghai China 《水动力学研究与进展(B辑)》2003,15(2)
1 . INTRODUCTIONUndertheinfluenceofnaturaltides,theinterac tionsbetweenflowfeaturesandpollutantlongitudinaldiffusionintidalriversareimportantforwaterenvi ronmentrectificationinestuarineregions.Thediffu sionandtransportofpollutantinnaturalriversfallin tom… 相似文献