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91.
92.
西部地区深井井身结构设计技术探讨 总被引:3,自引:2,他引:1
科学合理地确定井身结构及钻井液密度是深井超深井钻井的关键环节之一,其基础是准确建立地层孔隙压力、地应力、破裂压力、坍塌压力的钻前预测剖面。分析了西部地区目前深井井身结构的缺点和进行井身结构应考虑的问题,介绍了深探井井身结构的设计方法,并针对西部复杂地区的地层特点,建议采用3种增加技术套管的井身结构方案。塔河油田钻井实践表明,采用这3种井身结构方案后,深井机械钻速得到提高,钻井周期缩短,而且降低了钻井成本。 相似文献
93.
The phase behavior and volumetric properties of polyethylene (PE) in solutions of n‐pentane and n‐pentane/CO2 were studied in a temperature (T) range of 370–440 K at pressures up to 60 MPa. Measurements were conducted with a variable‐volume view‐cell system equipped with optical sensors to monitor the changes in the transmitted light intensity as the P or the T of the system was changed. Lower‐critical‐solution‐temperature‐type behavior was observed for all of the liquid–liquid (L–L) phase boundaries, which shifted to higher pressures in solutions containing CO2. The solid–fluid (S–F) phase boundaries were investigated over a P range of 8–54 MPa and took place in a narrow T range, from 374 to 378 K in this P interval. The S–F phase boundary showed a unique feature in that the demixing temperatures showed both increasing and decreasing trends with P depending on the P range. This was observed in both the PE/n‐pentane and PE/n‐pentane/CO2 mixtures. The density of these solutions were measured as a function of P at selected temperatures or as a function of T at selected pressures that corresponded to the paths followed in approaching the phase boundaries (S–F or L–L) starting from a homogeneous one‐phase condition. The data showed a smooth variation of the overall mixture density along these paths. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2201–2209, 2003 相似文献
94.
吐哈油田部分区块地层压力系数小于0.9,常规水基压井液对储层伤害大,若使用油基压井液成本高,环境污染严重。通过实验优选出了一种低密度水基微泡沫压井液。该压井液具有密度低、泡沫强度高、稳定性好、携砂能力强等优点。现场应用表明,低密度微泡沫压井液稳定时间大于48 h,密度在0.70~0.99 g/cm3之间可调,抗油污染能力强,抗油大于8%,抗温在100℃以上,岩心污染后渗透率恢复值大于80%;并且施工方便,成本低,具有储层保护能力,使用微泡沫压井液的井表皮系数在0.20~2.34之间。 相似文献
95.
The motional transition and heterogeneity of semi‐interpenetrating networks (SIPNs) based on polyurethane (PU) with carboxylic groups and methacrylic copolymer (PM) with tertiary amine groups were studied by the electron spin resonance (ESR) spin probe method. The concentration of functional groups in both prepolymers varied from 0 to 0.45 mmol g?1. Spin‐probed SIPNs show that the temperature‐dependent spectra are sensitive to polymer interactions imposed by functional groups. These interactions determine the free volume distribution in the matrix and temperature at which motional transition takes place. The fraction of free volume increases with functional group concentration and reaches its maximum at 0.25 mmol g?1. Further increases in the functional group concentration reduce the free volume. The results of the networks with strong interactions are discussed in terms of the interference of the plasticizing effect of the PU component and the formation of possible cluster cross‐links, which restricts segmental motions. Copyright © 2003 Society of Chemical Industry 相似文献
96.
Recent years have witnessed a rapid growth of interest in the study of the dynamic behavior of replenishment rules of bullwhip effect. We prove that bullwhip effect and butterfly effect share a same the self-oscillation amplifying mechanism that is the ordering decisions the supplier self-oscillation amplify the perturbations brought by the errors in the processing of retailers' demand information. This results as an explicit self-similar structure of the sensitivity of the system to the initial values duty to the nonlinear mechanism. In this paper, the causes process of the bullwhip effect is described as the internal nonlinear mechanism and study on the complexity of bullwhip effect for order-up-to policy under demand signal processing. The methodology is based on fractal and chaotic theory and allows important insights to be gained about the complexity behavior of bullwhip effect. 相似文献
97.
Reviews the book by Baruss (see record 2003-02669-000), which reviews the experimental and phenomenological research on alterations of consciousness, ranging from sleep and dreaming to mystical and near-death experience. The reviewer suggests there is a clear agenda announced by the book's subtitle, "An Empirical Analysis for Social Scientists." In the view of Baruss, all too often in states of consciousness research a preoccupation with theory has kept investigators from full engagement with the actual data. The book provides readable and at times appropriately controversial discussions of empirical literature on dreaming and lucid dreams, daydreaming and fantasy proneness, hypnosis, dissociative identity disorder, shamanism and possession states, psychedelic drug research, parapsychology, trance-chanelling and mediumship, the alien abduction syndrome, classical mystical experience, out-of-body and near-death experiences, and recent attempts by MacDonald and others to assess individual differences in spirituality through multifactor questionnaires. However, the reviewer believes that the breadth of coverage of both recent and past research is too often highly selective, and that the author's rejection of theory is both questionable in itself and more illusion than reality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
99.
HDPE/PS/HDPE-g-PS合金的相容性和力学性能研究 总被引:1,自引:0,他引:1
用自制接枝共聚物GR-Ⅰ、GR-Ⅱ相容剂研究其对HDPE/PS共混物相容性和力学性能的影响。通过SEM、DMA、DSC和力学性能测试表征,表明在HDPE/PS共混中加入这些相容剂其相容性和力学性能有一定提高 相似文献
100.
This article deals with the kinetics of two-step anionic polymerization by way of a non-steady state method. Several molecular parameters can be evaluated using the formulae developed. A bimodal molecular weight distribution function for the resulting polymer is derived from the set of kinetic differential equations, which is in agreement with the experimental data reported. 相似文献