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91.
原油基压裂液研究   总被引:5,自引:1,他引:4  
研制了一种适用于低压、低渗、水敏性储集层的新型原油基压裂液体系。根据基液原油的组分合成相应的增稠剂,增稠剂在原油中与交联剂反应,形成网状结构,使原油成为黏度可以调控的冻胶,从根本上改变了油基压裂液以柴油、煤油为基液的现状,降低了油基压裂液的成本,同时还提高了压裂液的抗温、抗剪切和破胶性能,并将交联时间缩短到2h以内,可以满足现场压裂施工的要求,大大降低了施工强度和压裂改造的综合成本。在青海油田进行的现场先导试验取得成功。图9表1参5  相似文献   
92.
Si3N4 ceramic was jointed to itself using a filler alloy of Cu76.5Pd8.5Ti15, and the mechanical properties of the jointwere measured and analyzed. By using a filler alloy of Cu76.5Pd8.5Ti15, the SisN4/SisN4 joints were obtained bybrazing at 1373~1473 K f  相似文献   
93.
提出了一种基于光纤环的光缓存器的结构,对结合半导体光放大器作光开关的此结构的物理模型进行了详细描述,并根据此模型分析了其增益、噪声、信噪比等方面的特性.  相似文献   
94.
Quality of service (QoS) support for multimedia services in the IEEE 802.11 wireless LAN is an important issue for such WLANs to become a viable wireless access to the Internet. In this paper, we endeavor to propose a practical scheme to achieve this goal without changing the channel access mechanism. To this end, a novel call admission and rate control (CARC) scheme is proposed. The key idea of this scheme is to regulate the arriving traffic of the WLAN such that the network can work at an optimal point. We first show that the channel busyness ratio is a good indicator of the network status in the sense that it is easy to obtain and can accurately and timely represent channel utilization. Then we propose two algorithms based on the channel busyness ratio. The call admission control algorithm is used to regulate the admission of real-time or streaming traffic and the rate control algorithm to control the transmission rate of best effort traffic. As a result, the real-time or streaming traffic is supported with statistical QoS guarantees and the best effort traffic can fully utilize the residual channel capacity left by the real-time and streaming traffic. In addition, the rate control algorithm itself provides a solution that could be used above the media access mechanism to approach the maximal theoretical channel utilization. A comprehensive simulation study in ns-2 has verified the performance of our proposed CARC scheme, showing that the original 802.11 DCF protocol can statically support strict QoS requirements, such as those required by voice over IP or streaming video, and at the same time, achieve a high channel utilization. Hongqiang Zhai received the B.E. and M.E. degrees in electrical engineering from Tsinghua University, Beijing, China, in July 1999 and January 2002 respectively. He worked as a research intern in Bell Labs Research China from June 2001 to December 2001, and in Microsoft Research Asia from January 2002 to July 2002. Currently he is pursuing the PhD degree in the Department of Electrical and Computer Engineering, University of Florida. He is a student member of IEEE. Xiang Chen received the B.E. and M.E. degrees in electrical engineering from Shanghai Jiao Tong University, Shanghai, China, in 1997 and 2000, respectively, and the Ph.D. degree in electrical and computer engineering from the University of Florida, Gainesville, in 2005. He is currently a Senior Research Engineer at Motorola Labs, Arlington Heights, IL. His research interests include resource management, medium access control, and quality of service (QoS) in wireless networks. He is a Member of Tau Beta Pi and a student member of IEEE. Yuguang Fang received a Ph.D degree in Systems and Control Engineering from Case Western Reserve University in January 1994, and a Ph.D degree in Electrical Engineering from Boston University in May 1997. From June 1997 to July 1998, he was a Visiting Assistant Professor in Department of Electrical Engineering at the University of Texas at Dallas. From July 1998 to May 2000, he was an Assistant Professor in the Department of Electrical and Computer Engineering at New Jersey Institute of Technology. In May 2000, he joined the Department of Electrical and Computer Engineering at University of Florida where he got the early promotion with tenure in August 2003 and has been an Associate Professor since then. He has published over one hundred (100) papers in refereed professional journals and conferences. He received the National Science Foundation Faculty Early Career Award in 2001 and the Office of Naval Research Young Investigator Award in 2002. He is currently serving as an Editor for many journals including IEEE Transactions on Communications, IEEE Transactions on Wireless Communications, IEEE Transactions on Mobile Computing, and ACM Wireless Networks. He is also actively participating in conference organization such as the Program Vice-Chair for IEEE INFOCOM’2005, Program Co-Chair for the Global Internet and Next Generation Networks Symposium in IEEE Globecom’2004 and the Program Vice Chair for 2000 IEEE Wireless Communications and Networking Conference (WCNC’2000).  相似文献   
95.
24万t/a尿素装置技术改造总结   总被引:2,自引:0,他引:2  
针对新化化肥有限公司尿素装置存在的问题进行了技术改造,从尿素合成塔、中压分解吸收、低压分解吸收、闪蒸等方面分析了产生问题的原因,提出了改进措施和实施方案。对改造前后工艺指标、产品质量和经济效益进行了对比和分析。改造结果表明.生产能力提高25%,5个月可收回全部投资。  相似文献   
96.
聚丙烯腈基碳纤维市场分析与预测   总被引:7,自引:2,他引:5  
本文介绍了国内外聚丙烯腈基碳纤维装置的生产能力和碳纤维的市场需求情况,提出了国内碳纤维所面临的挑战,并对如何发展国内碳纤维提了一些建议。  相似文献   
97.
恒星光干涉仪样机的总控系统   总被引:2,自引:0,他引:2  
控制系统以SCO公司的UNIX ODT为软件平台,普通PC机为总控计算机,通用8098单 片机系统作为前端机组成一个主从式两级管理系统,与PC机相连的16通道多用户卡通过RS-232与14个前端机通讯,进行实时控制和处理。用C语言编写了该样机的总控软件,前端机的通讯程序和相关控制部件的控制程序。经过调试,实现了对样机的全自动控制。  相似文献   
98.
脉冲液体射流泵时均值基本方程中的流速系数   总被引:4,自引:0,他引:4       下载免费PDF全文
运用非恒定的动量方程和时均值计算方法,对脉冲液体射流泵时均值基本方程中的流速系数进行了理论研究,推导出了喉管和喉管进口段流速系数φ2和φ5的计算式。通过与恒定射流的流速系数计算式对比,阐明了脉冲频率是影响φ2和φ5的主要因素,沟通了脉冲射流与恒定射流流速系数之间的关系。  相似文献   
99.
含缺陷压力管道经缺陷评定合乎使用后,其疲劳寿命的估计具有重要的工程意义。将整个含缺陷压力管道作为一个整体,分析了含缺陷压力管道的疲劳裂纹扩展特点,提出了相应的含缺陷压力管道疲劳寿命的计算过程,并在基于可靠性评价的基础上,给出了核压力管道的可接受失效概率,最终得到了含缺陷核压力管道疲劳寿命预测方法。  相似文献   
100.
为减少勘探费用,缩短施工周期,取全取准各项地质资料,采取中途测试工艺。随着深井中途测试不断增多,特别是跨隔支撑测试具有一定施工风险和难度,要求测试质量不断提高。结合油田生产实际,合理选配了地层测试工具仪表,不断改进测试管串和优化施工设计,经盐22井中途跨隔测试应用,获得成功。  相似文献   
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