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31.
32.
本文旨在通过对石墨防爆片的变形、应力分布及爆破压力的试验研究,探讨以石墨电极为原材料加工石墨防爆片的可行性。文中运用有限单元法及薄板理论对该防爆破片的应力分布做了初步分析,并以电测和爆破试验验证了以薄板理论为基础的爆破压力计算公式,可供进一步研究时参考。 相似文献
33.
34.
Wei Wu 《Chemical engineering science》2003,58(15):3565-3570
Experiment was conducted on the threshold pressure for atmospheric air through unconsolidated narrow size distributed mini sphere and sand particles at low flow rates. The threshold diameter calculated from measured threshold pressure showed that it does not follow the traditional similarity theory. This is consistent with our experiment on accurate permeability measurement, and can be explained as a result of gas slip flow within such micro pore structure. Our current work tend to find the method to predict the permeability-threshold pressure relationship for unconsolidated porous structures. 相似文献
35.
In a recent communication it was shown that the pressure losses during the solid phase compaction of a polymeric powder could be predicted from a simple relationship of the form: where is a function of the geometry of the compact. This has now been explored in more detail and it has been found that for PVdC and PVC the factor K is dependent on the rate of compaction and the die surface finish but is independent of compaction pressure and die diameter. To illustrate the effect of the pressure losses on the structural uniformity of the compacts, microhardness measurements were taken at a large number of points across a section of each sample. A computer plot of hardness contours provided a picture of the homogeneity of the sample which could be related to the compaction conditions and average density of the compact. 相似文献
36.
High temperature, high pressure e.s.r. measurements of the hydrogenation reaction of Taiheiyo coal in the presence of catalysts were carried out to understand the stabilization of thermally and/or catalytically induced free radicals. A decrease in free radical concentration with increasing temperature was observed for ZnCl2 and SnCl2 · 2H2O catalysts at 10MPa under hydrogen gas. High pressure modified single-cell d.t.a. and p.d.a. equipment augmented the uniquely designed high temperature, high pressure e.s.r. cell. The hydrogenation reaction was monitored under the same experimental conditions as for e.s.r. From the results of the combination of high temperature, high pressure e.s.r. with high pressure d.t.a. and p.d.a., it was established that H2 molecules can react efficiently with free radicals from coal molecules created by the presence of ZnCl2 and SnCl2 · 2H2O catalysts. 相似文献
37.
The characteristics of gas bubbles in a 5 cm diameter bubble column equipped with a single orifice of 1,3 or 5 mm diameter were investigated under system pressure of 0.1-15 MPa. The formation of gas bubbles was strongly affected by the system pressure. Under high pressures a dispersed gas jet was formed at gas velocities where spherical gas bubbles would have been formed at atmospheric pressure. The critical gas velocity between the bubbling regime and the jetting regime was correlated with the liquid phase Weber number and the gas phase Reynolds number based on the gas velocity at the orifice. Bubble size and gas holdup in the main part of the bubble column were also affected by the bubble formation pattern at the distributor 相似文献
38.
Taisuke Ito 《Polymer》1982,23(10):1412-1434
Results for the compressibilities of a wide range of polymer crystals along the fibre- and the transverse crystal axes are presented. Good agreement is found between the theoretical and the experimental results of different authors. 相似文献
39.
阐述了在D级压力容器制造许可证取换证鉴定评审过程中,取换证制造企业存在的较为普遍的问题。 相似文献
40.
大压差减温减压是能的严重贬值。根据公司供热现状,分析了热电联产的可行性,利用蒸汽余压发电后,再供生产系统各热用户,这样既节约了能源又缓解了集团公司用电紧张的局面,而且有相当可观的经济效益。 相似文献