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排序方式: 共有9693条查询结果,搜索用时 15 毫秒
11.
非对称单筒双井技术在文昌13-2油田的应用 总被引:4,自引:0,他引:4
南海西部文昌13-2油田目前共有开发井12口,油田已经没有空井槽,为充分开发油田,提高采收率,确定在文昌13-2油田A平台内挂4个?762 mm井槽,采用单筒双井技术,利用平台125t修井机,在?762 mm隔水管内下入?339.7 mm套管和?244.5mm套管,并利用?339.7 mm套管进行单筒双井的固井作业,实现了在同一井槽内完成2口不同井身结构的水平井钻完井作业。以同一槽口A16h井和A17h井为例,介绍了非对称单筒双井钻井程序、工艺特点以及钻井期间注意事项。单筒双井技术在文昌13-2平台成功的应用,充分地利用了井口平台的空间,减少了工程造价,降低了开发成本,摸索出了一套成功经验。 相似文献
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滑石质瓷是一种高性能瓷的材料,但由于其泥浆的稠化性及泥料塑性差,阻碍了滑石质瓷的大量生产。实验表明:引入长石作助熔剂并加入适量粘土,可以改进泥料塑性及泥浆流变性能,使烧成变形度小,机械强度提高,能较好地满足制品成型的工艺要求。实验中设计了多组配料,分析比较烧后试样的性能测试结果,确定最佳配方及烧结温度。 相似文献
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以无线通讯方式实现多台PLC之间以及PLC与微机之间的数据交换,在遥控监控站上完成对移动设备的控制与监视。 相似文献
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D Becker Y Razskazovskii MU Callaghan MD Sevilla 《Canadian Metallurgical Quarterly》1996,146(4):361-368
A major problem in the intensive care unit nowadays is the development of multiple organ dysfunction syndrome (MODS), a cumulative sequence of progressive deterioration of organ functions. While the pathogenic pathways of MODS remain to be elucidated, it is assumed that cells of the host defence system, especially the macrophages, are altered in their function. During the development of MODS it is assumed that macrophages are overactivated and that an exaggerated inflammatory response may contribute to its pathogenesis. In order to gain insight into the alterations of the functional status of the macrophage during the development of MODS, a series of macrophage functions was measured in the subsequent phases of zymosan induced generalized inflammation in mice. Male C57BL/6 mice received a single dose of zymosan intraperitoneally and groups of animals were killed after 2, 5, 8, and 12 days. Peritoneal macrophages were collected for in vitro assessment of the ADCC, the production of superoxide (O2-) and nitric oxide (NO), and complement mediated phagocytosis and intracellular killing of Staphylococcus aureus. A single intraperitoneal injection with zymosan resulted in a three-phase illness. During the third phase the animals developed MODS-like symptoms. Peritoneal cells from control animals produced very low to non-detectable amounts of O2- and NO, and the cytotoxic activity was also low. During the development of MODS, from day 7 onwards, the ability to produce O2- and NO2- became strongly elevated, as did the cytotoxic activity. These findings are in parallel with the development of MODS whereas the phagocytic and killing capacity remained essentially unaltered. The changes found could be detrimental for the organism, thus possibly contributing to the onset and development of MODS. 相似文献
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The lack of efficient security guidance is a prominent problem in the design flow of high-level synthesis. To tackle this issue, this paper proposes a security-based high-level synthesis design flow featuring the power side-channel vulnerabilities. The side-channel leakage is quantified by establishing a secure component module library, a more efficient and secure parallel scheduling mechanism is generated by optimizing the control flow, and a more secure architecture of the storage system is achieved by optimizing the data flow. The goal is to perform tradeoffs between performance and security, reducing the side-channel risks at the early stage of design and simultaneously generating more secure and efficient cryptographic cores in hardware. Furthermore, the proposed HLS design flow is verified on a field programmable gate array platform. Experimental results show that, in comparison with the traditional design flow, this method reduces the resources by 72% and the clock cycles by 70% and increases the throughput by 88%, and that it can lower the power side-channel risks within an ongoing design to the greatest extent. 相似文献
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穆弈君 《数码设计:surface》2012,(6):112-114
动画角色类型化、系列化设计是动漫产业向多元化发展的一环,它能使动画片中角色更感人,更具明星效应,同时产生更大的商业附加值。在我国,动画角色造型质量上不去这一现象,这已成为阻碍中国动画设计产业不断发展的重要瓶颈。文章主要分析美国、日本经典动画片中角色的类型化、系列化,找到他们合乎时代要求并成功的原因,得出趋同、趋异的动画角色系列化设计方法,为创新角色设计找到可以依据的途径。 相似文献
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Wang Weihua Xu Wenjie Song Weilin Yang Bin Li Li Guo Xuhong Wu Lianghua Liu Hongxing 《Catalysis Letters》2021,151(8):2326-2338
Catalysis Letters - Novel Mo-V-PMMA and Mo-V-PS catalysts are prepared by addition of hard polymethyl methacrylate (PMMA) and polystyrene (PS) nanospheres into Mo/V compounds in the preparation... 相似文献