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1.
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   
2.
介绍了粉末涂料的组成、优越性以及各种性能,分析了粉末涂料在汽车涂装中的经济性,肯定了粉末涂料在汽车工业中的应用前景。  相似文献   
3.
概述了高压放大器的基本组成,以及采用高压稳压电源措施,提高高压放大器的性能,并简述了高压放大器输出级的工作原理,给出了过渡保护方法。  相似文献   
4.
Novel algorithms for shared segment protection   总被引:8,自引:0,他引:8  
The major challenges in designing survivable schemes are how to allocate a minimal amount of spare resources (e.g., bandwidth) using fast (e.g., polynomial-time) algorithms, and, in case a failure occurs, to be able to recover quickly from it. All existing approaches invariably make tradeoffs. We propose novel shared segment protection algorithms which make little or no compromise . We develop an elegant integer linear programming (ILP) model to determine an optimal set of segments to protect a given active path. Although the ILP approach is useful for a medium-size network, it is too time consuming for large networks. Accordingly, we also design a fast heuristic algorithm based on dynamic programming to obtain a near-optimal set of segments. Although the heuristic algorithm has a polynomial time complexity, it can achieve a bandwidth efficiency as high as some best-performing shared path protection schemes and, at the same time, much faster recovery than these shared path protection schemes. The proposed scheme is also applicable to a wide range of networking technologies, including Internet Protocol and wavelength-division multiplexing networks under the generalized multiprotocol label switched framework.  相似文献   
5.
Achieving fast and bandwidth-efficient shared-path protection   总被引:4,自引:0,他引:4  
Dynamic provisioning of restorable bandwidth guaranteed paths is a challenge in the design of broad-band transport networks, especially next-generation optical networks. A common approach is called (failure-independent) path protection, whereby for every mission-critical active path to be established, a link (or node) disjoint backup path (BP) is also established. To optimize network resource utilization, shared path protection should be adopted, which often allows a new BP to share the bandwidth allocated to some existing BPs. However, it usually leads the backup paths to use too many links, with zero cost in term of additional backup bandwidth, along its route. It will violate the restoration time guarantee. In this paper, we propose novel integer linear programming (ILP) formulations by introducing two parameters (/spl epsi/ and /spl mu/) in both the sharing with complete information (SCI) scheme and the distributed partial information management (DPIM) scheme. Our results show that the proposed ILP formulations can not only improve the network resource utilization effectively, but also keep the BPs as short as possible.  相似文献   
6.
Crosstalk in multistage interconnection networks can be avoided by ensuring that a switch is not used by two connections simultaneously, in order to support crosstalk-free communications among N inputs and N outputs, a space domain approach dilates an N×N network into one that is essentially equivalent to a 2N×2N network. Path conflicts, however may still exist in dilated networks. This paper proposes a time domain approach for avoiding crosstalk. Such an approach can be regarded as “dilating” a network in time, instead of space. More specifically, the connections that need to use the same switch are established during different time slots. This way, path conflicts are automatically avoided. The time domain dilation is useful for overcoming the limits on the network size while utilizing the high bandwidth of optical interconnects. We study the set of permutations whose crosstalk-free connections can be established in just two time slots using the time domain approach. While the space domain approach trades hardware complexity for crosstalk-free communications, the time domain approach trades time complexity. We compare the proposed time domain to the space domain approach by analyzing the tradeoffs involved in these two approaches  相似文献   
7.
曲流河沉积亚相的地震识别方法   总被引:7,自引:1,他引:6  
本文提出利用三维地震资料相干数据分析研究曲流河沉积相的方法,其优点是在地质分析的基础上,对沉积体系有较为明显的识别特征,且在钻井较少的地区尤为实用。该方法在济阳拗陷东北部上第三系应用中取得了较为明显的效果。  相似文献   
8.
分析了重油催化裂化沉降器结焦的原因,认为反应油气中含有催化剂颗粒以及油气中重组分的冷凝是沉降器结焦的物理原因,而重芳烃、胶质、沥青质的高温缩合则是沉降器结焦的化学因素。因此,防止沉降器结焦的关键是抑制油气重组分的冷凝和减少油气在沉降器内的停留时间。  相似文献   
9.
Ab initio method was employed to determine the mechanism of alkylation reaction of 2-butene with isobutane. The results indicated that 2-butene is rapidly protonated to form sec-butyl carbonium ion, which then reacts with isobutane to form tert-butyl carbonium ion. The resulting carbonium ion is then deprotonated to form isobutene that reacts rapidly with tert-butyl carbonium ion to form trimethylpentane (TMP) carbonium ion. Finally, the TMP+ carbonium ion is converted to TMP via the hydride transfer process. The transition states of the interactions were obtained by using the SCAN method (a calculation key word for potential energy surface) first and then the intrinsic reaction coordinates were traced using the Gaussian program. In addition, the energy changes and geometric parameters of the interactions were analyzed. The computed results indicated that the energy barriers are close to or less than zero for the interaction of isobutane with protonated 2-butene or for the interaction of tert-butyl carbonium ion with isobutene, suggesting rapid reaction steps of the carbonium ions. The 2,2,3-TMP is kinetically controlled, while the formation of 2,2,4-TMP is controlled by reaction equilibrium. The calculated results were in good agreement with the experimental results.  相似文献   
10.
杨峰  刘春明  肖华 《中国水利》2007,(10):47-48
雁栖水厂位于北京市怀柔区雁栖镇下庄村南,距怀柔县城6km,占地面积0.78hm^2.设计日供水能力5000t。雁栖水厂集中反映了北京市农村安全饮水工作的模式和经验,下面从规划、设计、管理等三方面对雁栖水厂进行介绍。  相似文献   
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