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41.
可膨胀波纹管技术在韦15-19井的应用 总被引:10,自引:4,他引:6
可膨胀管包括可膨胀实体管和可膨胀波纹管,主要用于在不减小井眼尺寸的情况下封堵各种复杂地层,对损坏套管进行补贴修复,作为各种井筒封隔器以及延长技术套管长度。实体管和波纹管两者膨胀机理不一样,相比之下,可膨胀波纹管技术具有膨胀工艺简单,作业周期短的优点,该技术一直由俄罗斯掌握。中国石化勘探开发研究院经过多年的潜心研究,终于形成了具有自主知识产权的可膨胀波纹管产品及其配套的工艺技术,新研制的可膨胀波纹管壁厚8mm,抗内压强度35MPa,抗外挤强度10MPa,并在江苏油田韦15—19井进行了漏层封堵现场试验,经过扩眼、管串下入、水力膨胀、机械膨胀等工艺后获得圆满成功,标志着我国已经打破了国外公司对该技术的垄断,填补了国内在该领域的技术空白。 相似文献
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The evaporation kinetics of Zn and Pb from liquid iron at 1600°C were studied under argon pressure 0.1 to 50 bar in an induction furnace. It was found that the limiting step of evaporation under pAr < 1 bar is diffusion in the melt. Diffusion in the gas phase becomes rate-determining with increasing argon pressure. The phase boundary reaction has no effect on the evaporation of Zn and Pb. The evaporation of Zn can evidently be reduced by increasing argon pressure above 1 bar, while the evaporation of Pb is not significantly effected by changes of argon pressure. 相似文献
45.
在浸泡、阴极极化、阴极极化同时迭加拉伸变形、添加As2O3毒化剂等常见致氢条件下,通过慢应变速率拉伸试验研究了SiCp/2024复合材料的力学性能,考察了断口形貌.测定了该材料在按几种常用充氢条件充氢后的氢含量.发现虽然强烈阴极极化使材料力学性能下降,但其原因在于阴极极化引起的碱性腐蚀,与氢脆无关.获得了不同于前人研究的新结论:在本文试验条件下SiCp/2024材料不发生氢脆,也不发生不可逆氢损伤,其原因与该材料难以充入氢有关. 相似文献
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Phospholipid transfer protein (PLTP) was purified from lipoprotein-free human plasma, obtained upon treatment of plasma with dextran sulfate and Ca2+, by employing a series of column chromatography. Upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the purified PLTP showed a single main band, corresponding to the molecular mass of 78 kDa. However, isoelectric focusing of the purified preparation gave multiple bands with pI ranging from 4.3 to 5.1, indicative of microheterogeneity. Purified PLTP was shown to possess not only phospholipid transfer activity, but also high density lipoprotein (HDL) conversion activity (Tu, A.-Y., Nishida, H. I., and Nishida, T. (1990), FASEB J. 4, A2148; Jauhiainen, M., Metso, J., Pahlman, R., Blomqvist, S., van Tol, A., and Ehnholm, C. (1993) J. Biol. Chem. 268, 4032-4036). Isolated HDL3 was enlarged to the size of HDL2b upon incubation with purified PLTP for 6 h at 37 degrees C at the PLTP/HDL3 molar ratio of approximately 1:45. Both the HDL conversion and the phosphatidylcholine transfer activities of purified PLTP were effectively inhibited by rabbit anti-PLTP immunoglobulin G. The primary importance of PLTP in the HDL enlargement that occurs in human plasma upon incubation at 37 degrees C was shown by the strong inhibitory effect of the anti-PLTP immunoglobulin G. The process of PLTP-mediated HDL enlargement was accompanied by the release of apoproteins, primarily apoA-I. HDL3 enlargement mediated by PLTP was effectively inhibited by the addition of free fatty acids. 相似文献
50.
Effect of stress triaxiality levels in crack tip regions on the characteristics of void growth and fracture criteria 总被引:1,自引:0,他引:1
The behaviour of void growth in the crack tip regions of four specimen geometries with different stress triaxiality levels have been investigated by the FEM method and experimental observations in plane strain and plane stress cases respectively. It was found that the shape change of growing voids, the configurations of a blunting crack tip and the sizes of decreasing ligament between the void and the crack tip are strongly dependent upon the stress triaxiality levels. Under the condition of plane stress, the stress triaxiality on the ligaments of cracks are nearly the same for different specimen geometries, also the void growth, crack tip blunting asnd decreasing of ligament size are identical for various specimens with increasing load levels, which lead to the conclusion that the Ji-value is independent of specimen geometries. However, in the plain strain case, different void growth, crack tip blunting and decreasing in ligament size for various stress triaxiality levels directly caused the Ji-value to be dependent on the specimen geometries. It was found that when the void is linked to the blunting crack tip by the extrapolation to the zero ligament from FEM calculations, the Ji values, measured experimentally, are underestimated slightly. 相似文献