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51.
胜科1井钻井事故的预防与处理 总被引:2,自引:1,他引:1
胜科1井设计井深7 000 m,完钻井深7 026 m。在该井钻井过程中,针对上部大尺寸钻头破岩效率低、大井眼井壁稳定性差、大段盐膏层、膏岩层的塑性蠕变和塑性流动造成井眼复杂、超深井高温高压给钻井液性能的控制和水泥浆调控等带来的一系列技术难题,制定了一整套预防井下事故和复杂情况的技术措施,从而确保了该井的钻探成功。该井在钻井过程发生了2次断钻具事故和1次卡钻事故,根据超深井的特点,采取了较为稳妥的处理措施,同时,有针对性地研制了高效铣环和PDC钻头专用打捞器,3次事故处理均获得了成功,共耗时38.5 d。详细介绍了该井所采取的预防和处理钻井事故的技术措施,可为其他超深井的钻井施工提供一定的借鉴。 相似文献
52.
53.
L. V. El’nikova 《Journal of Superconductivity and Novel Magnetism》2007,20(2):197-199
We describe the lyotropic liquid crystalline phase transitions in the lipid mixture dipalmitoil-PC/dilauroy-PC/cholesterol
by 3D spin-1 lattice model. The formation of nanoscale domains with the characteristic size about 300 nm was studied in experiments
on confocal fluorescence microscopy (CFM) (G. V. Feigenson and J. T. Buboltz, Biophys. J.
80, 2775 (2001)). The structure parameters of the lamellar vesicle in dipalmitoil-PC-rich phase, corresponding to these regions,
are verified by numerical Monte Carlo simulations on the lattice. We point its superconductivity analogy properties at the
region of phase stability for composition-dependent nanoscopic region. 相似文献
54.
采用SE 3 0为固定液进行色谱柱分离 ,用外标定量法测定泥土中的微量六氯环戊二烯 ,结果最小检知量为 0 .18× 10 - 6 ,相关系数为 0 .99992。 相似文献
55.
通过适当的工艺措施,采用Bridgman法生长了直径为30mm的X射线及γ射线探测器级的Cd.9Zn0.1Te晶锭.测试结果表明:该晶锭结晶质量良好,位错密度低,成分均匀,杂质含量低,红外透过率和电阻率都十分接近本征Cd.9Zn0.1Te的值.并从晶体的生长特性、缺陷和杂质的角度,分析了生长高性能晶体的条件,研究了生长Cdl-xZnxTe晶体的x值与缺陷和杂质浓度之间的关系. 相似文献
56.
A ternary blend system comprising poly(cyclohexyl methacrylate) (PCHMA), poly(α‐methyl styrene) (PαMS) and poly(4‐methyl styrene) (P4MS) was investigated by thermal analysis, optical and scanning electron microscopy. Ternary phase behaviour was compared with the behaviour for the three constituent binary pairs. This study showed that the ternary blends of PCHMA/PαMS/P4MS in most compositions were miscible, with an apparent glass transition temperature (Tg) and distinct cloud‐point transitions, which were located at lower temperatures than their binary counterparts. However, in a closed‐loop range of compositions roughly near the centre of the triangular phase diagram, some ternary blends displayed phase separation with heterogeneity domains of about 1 µm. Therefore, it is properly concluded that ternary PCHMA/PαMS/P4M is partially miscible with a small closed‐loop immisciblity range, even though all the constituent binary pairs are fully miscible. Thermodynamic backgrounds leading to decreased miscibility and greater heterogeneity in a ternary polymer system in comparison with the binary counterparts are discussed. © 2003 Society of Chemical Industry 相似文献
57.
Five new salts based on 1-alkyl-2-methyl pyrrolinium ion are reported, two involving the iodide ion and three involving the bis(trifluoromethanesulfonyl) amide ion. The iodide salts have melting points around 100 °C, while the amide salts have melting points around room temperature. Two of the amide salts can be easily quenched into the glassy state and exhibit glass transition temperatures around −70 °C. The 2-methyl pyrrolinium cation bears structural similarities to the aromatic imidazolium cations on one hand and the cyclic ammonium cation family based on the pyrrolidinium cation on the other. The properties of the salts reported here are compared within these two related families of salts. 相似文献
58.
K. Y. Cheah T. S. Tang Fujio Mizukami Shu-ichi Niwa Makoto Toba Y. M. Choo 《Journal of the American Oil Chemists' Society》1992,69(5):410-416
A new catalyst, ruthenium-tin-alumina is found to selectively hydrogenate oleic acid to 9-octadecen-1-ol (oleyl + elaidyl
alcohol) at low pressure with high yield. Catalyst preparation methods, catalyst raw materials and activation conditions have
a significant effect on the activity of the catalyst. The optimum atomic ratio of ruthenium to tin is about 1:2. Catalyst
prepared by an improved sol-gel method shows higher activity and selectivity than catalysts prepared by impregnation and coprecipitation
methods. Chloride is found to have a negative effect on catalytic activity. The best catalyst is prepared from chloride-free
ruthenium and tin raw materials. Under the optimum reaction conditions of 250°C and 5.6 MPa, the selectivities for 9-octadecen-1-ol
and total alcohol (9-octadecen-1-ol + stearyl alcohol) formation are 80.9% and 97%, respectively, at a conversion of 81.3%. 相似文献
59.
J. Gegner Priv.‐Doz. Dr. W. Nierlich M. Brückner 《Materialwissenschaft und Werkstofftechnik》2007,38(8):613-623
Due to clearly distinguishable damage symptoms, it is differentiated between the surface and sub‐surface failure mode of rolling bearings. Material states red out by X‐ray diffraction (XRD) residual stress measurements point to a variety of loading conditions especially at raceway surfaces that are associated with several competing failure mechanisms. The corresponding lifetime reduction can range from the lower fatigue strength region to material ratcheting in extreme cases. Relevant position of the microstructural changes and nature of the failure mechanisms are characterized. The time alteration of the XRD material parameters measured at or near the surface and at the depth of the maximum equivalent stress correlates, in a different manner, with the statistical parameter of the 10 % bearing life. Both failure modes are illustrated by concrete examples. Contaminated lubricant and boundary lubrication, which represent practically important surface‐induced failures, are discussed in more detail. Gray staining, i.e. shallow pitting, often occurs without distinct indication of global material aging by means of XRD characteristics. Here, scanning electron microscopy observations and electron microprobe analyses point to corrosion fatigue as acting surface failure mechanism. The interaction between material and lubricant under complex loading regimes particularly of mixed friction and corrosion opens further failure research areas in the field of tribology. 相似文献
60.
The thermal expansion of a titanium modified, swelling resistant austenitic stainless steel designated as D9 is studied by measuring the lattice parameter as a function of temperature in the range 300-1300 K by high-temperature X-ray diffraction technique. The thermal expansion data thus obtained is in reasonable agreement with the typical thermal expansion values reported for similar nuclear grade austenitic stainless steels. However, at temperatures exceeding 900 K, the measured thermal expansivity exhibits a pronounced non-linear increase due partly to the precipitation of complex carbide and intermetallic phases. The high-temperature thermal expansion data obtained in the present study are augmented by modelling the low-temperature thermal expansion behaviour by Grüneisen formalism. 相似文献