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151.
百49油藏属典型的低渗透复杂断块油藏,地层倾角较大,开发难度大,含水上升快,目前已进入高含水期。针对影响油田开发生产的不利因素,充分利用新理论、新技术、新方法,油藏先后经历了压裂、酸化、补孔以及注水等措施,在高含水期实施了大修扶躺、封堵换层、周期注水等措施。现场实践取得了较好的效果,对油田增产、稳产发挥了较大作用。实现了低渗透复杂断块油藏高含水期的增储上产,有效控制了含水上升率,增加了可采储量,改善了油田开发效果。对其它同类低渗复杂断块油藏高含水期开发具有一定的借鉴作用。 相似文献
152.
传统的弹性地基系数"m”法在计算抗滑桩或其他横向受荷桩内力时,由于需查表手算,不但计算过程繁琐,容易出错,而且受查用表格中各系数误差的影响,常使计算结果出现不同程度的误差.为此,作者基于"m”法的原理,提出了进行抗滑桩全桩内力计算的有限差分法.同时,编写了该法计算和图形处理程序,与传统方法进行了验证和对比.实例计算结果表明只要等量差分段取得足够小,虽然所耗机时稍长,但可获得高精度数值解,其精度高于采用传统手算法所得解的精度,而且程序图形处理结果可优化抗滑桩的结构设计;该方法也可用来分析其他横向受荷桩,如桥梁桩基、海洋石油钻井平台桩基等的内力. 相似文献
153.
田晓青 《科技情报开发与经济》2006,16(4):293-294
根据文峪河水库右岸山体的地形地质特点、所处位置的重要性及稳定分析成果,提出了右岸山体稳定的关键是降低地下水位、防止软弱夹层泥化,并针对地下水的来水途径提出了相应的加固措施。 相似文献
154.
Doga Kavaz Amina Lawan Abubakar Nahit Rizaner Huzaifa Umar 《Molecules (Basel, Switzerland)》2021,26(13)
Nano-based particles synthesized via green routes have a particular structure that is useful in biomedical applications as they provide cheap, eco-friendly, and non-toxic nanoparticles. In the present study, we reported the effect of various concentrations of Zinc oxide nanoparticles synthesized using A. lebbeck stem bark extract (ZnO NPsAL) as stabilizing agent on rat biochemical profiles and tissue morphology. Adult Wistar rats weighing 170 ± 5 g were randomly classified into eight groups of five rats each; Group A served as a control fed with normal diet and water. Groups B1, B2, C1, C2, D1, D2, and E were treated with 40 mg/kg and 80 mg/kg of the 0.01, 0.05, and 0.1 M biosynthesized ZnO NPsAL and zinc nitrate daily by the gavage method, respectively. The rats were anesthetized 24 h after the last treatment, blood samples, kidney, heart, and liver tissues were collected for biochemical and histopathological analysis. The rats mean body weight, serum alkaline phosphatase, alanine aminotransferase, creatinine, urea, bilirubin, protein, albumin, globulin, total cholesterol, triacylglycerol, and high-density lipoprotein were significantly altered with an increased concentration of biosynthesized ZnO NPsAL when compared with the control group (p < 0.05; n ≥ 5). Furthermore, histopathological analysis of treated rats’ kidney, heart, and liver tissue revealed vascular congestion, tubular necrosis, inflammation, and cytoplasmic vacuolation. Biosynthesized ZnO NPsAL showed significant alteration in biochemical parameters and tissue morphology in rats with increasing concentrations of the nanoparticles. 相似文献
155.
《光谱学快报》2012,45(10):677-686
AbstractCobalt oxide nanoparticles were synthesized using a facile and convenient sonochemical method, followed by a calcination process. For the synthesis, cobalt nitrate, and sodium borohydride were used as precursors. Polyvinyl alcohol, 3-mercaptopropionic acid, and styrene were used as a stabilizing agent. To identify the structure, optical properties and morphology, the synthesized nanoparticles were characterized using X-ray diffraction, Ultraviolet-Visible Spectroscopy, Fourier-transform infrared spectroscopy, transmission electron microscopy, and scanning electron microscopy. To explain the formation mechanism of cobalt oxide nanoparticles, some investigations were carried out before thermal annealing. In addition, the particle size was tuned by variation of the concentration of 3-mercaptopropionic acid. 相似文献
156.
R. Sathyamoorthy P. Sudhagar R. Saravana Kumar T. M. Sathyadevan 《Crystal Research and Technology》2010,45(1):99-103
In recent years thiol‐functionalized cadmium telluride nanoparticles act as a core layers for obtaining high photovoltaic efficiency in conjugated polymer/inorganic nanocrystal solar cells and also provide easy tuning of quantum size effect by varying thiol groups and processing temperature. In this work, thiol functionalized CdTe nanoclusters were prepared for different tellurium concentrations at low temperature and its impact has been discussed. Structural parameters estimated by X‐ray diffraction revealed hexagonal phases at lower tellurium concentration and cubic phase at higher tellurium concentrations. Surface morphology of the samples analyzed by transmission electron microscopy, exhibited cluster type of morphology. Optical band gap energy estimated by diffused electron microscopy showed an increase with Te content and band edge emission has been observed in the photoluminescence spectra of CdTe nanoclusters around 620 nm. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
157.
高分子土壤结构改良材料的研究及应用 总被引:11,自引:0,他引:11
介绍了高分子土壤结构改良材料的发展简史、主要种类及其作用机理,提出了这种材料在沙漠化治理、防治水土流失、以及在水利和道路工程建设等方面的应用前景。 相似文献
158.