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11.
任丘潜山油藏剩余油的再聚集模式及分布预测 总被引:3,自引:2,他引:1
任丘潜山油藏位于冀中坳陷饶阳凹陷,为双重孔隙介质的底水块状油藏[1],构造裂缝发育,产油层位是中元古界蓟县系雾迷山组,岩性以隐藻白云岩为主,颗粒白云岩次之,夹有泥质白云岩,。含泥质白云岩,储集空间可分成孔,洞,缝三大类,该油藏1975年发现,历经投产,高产稳产和产量迅速下降阶段,目前处于产量缓民递减阶段,在注水开发过程中,随着油水界面上升,油藏水淹体积加大,采液指数不断上升而要油指数不断下降,导致采油速率和产油量下降。 相似文献
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超小型高温光电倍增管和能谱型管在测井中的应用 总被引:1,自引:0,他引:1
本文简要介绍了高温光电倍增管超小型化的措施,还介绍了这种管子和能谱型光电倍增管在开发测井方面的应用。 相似文献
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Design and modelling of a passive wireless pressure sensor 总被引:2,自引:0,他引:2
J. Zhai 《CIRP Annals》2010,59(1):187-190
This investigation is concerned with the design and modelling of a passive wireless pressure sensor to detect blood pressure inside an abdominal aortic aneurysm sac after endovascular repair of the aneurysm. The sensor consists of a coil and a capacitor to form an inductor-capacitor (LC) resonant circuit which oscillates electrically at its resonant frequency. This miniature sensor has a size of 6 mm × 6 mm × 1 mm and can be fabricated by microelectromechanical system (MEMS) technology. By activating the sensor with an electromagnetic field, aneurysm sac pressure information can be acquired. The properties and behaviour of this sensor based on computer simulation are also presented in this paper. 相似文献
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Negative-refractive-index transmission-line (NRI-TL) metamaterials comprise transmission lines loaded periodically with series capacitors and shunt inductors, such that the phase flow and power flow are contra-directional on the lines. These NRI-TL media exhibit properties that can be utilized for miniaturizing microwave components and antennas. In this mainly review paper, a compact antenna, power divider and branch-line coupler are presented to demonstrate the miniaturization techniques enabled by NRI-TLs. Furthermore, a generalized NRI-TL is described that exhibits two left-handed and two right-handed bands. This can be exploited for realizing compact dual-band and quad-band RF/microwave components. This generalized NRI-TL can be designed to exhibit two distinct frequencies where the corresponding propagation constants vanish. 相似文献
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Tensile Test of very thin Sheet Metal and Determination of Flow Stress Considering the Scaling Effect 总被引:1,自引:0,他引:1
H. Hoffmann 《CIRP Annals》2006,55(1):263-266
The reduction in size of mechanical parts is becoming more and more important in metal forming processes. This trend towards miniaturization leads to new requirements regarding the material and the product. The main object of this research is the so-called scaling effect which can occur during the forming process of very thin sheet metals. The goal is to determine and investigate variables which considerably influence the scaling effect. The optimisation of such forming processes needs a more comprehensive use of simulation and finite element analysis. The conventional model used for large and thick sheet specimens is not sufficient yet. Existing research reports on this topic show that among other things the thickness and the grain size of the material influence the scaling effect. Thus it is important to consider these material characteristics in the determination of the flow stress curve. In this paper the flow stress curve is investigated on a micro scale of up to 10μm specimen thickness considering different sheet thicknesses and widths. 相似文献
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This paper demonstrates research carried out towards the development of switched capacitors having miniature dimensions. Such devices are based on the Radio Frequency Micro Electro Mechanical Systems (RF MEMS) technique which has gained prominence in implementing a wide variety of microwave and millimetre devices till date. Switched capacitors having standard or conventional dimensions are prone to several limitations which are addressed by scaling down the standard dimensions by 150× times (in terms of area requirement). Such switched capacitors are employed to develop phase shifters working in K-band (22 GHz) frequency range to yield appreciable performance both in terms of electromechanical and RF characterizations. Such switched capacitors are utilized to develop phase shifters which find immense applications in the design of Phased Array RADARs. Switched capacitors fabricated on 500 µm thick quartz substrates, result in 30° phase shift (0.66 mm × 1 mm in dimension) with associated minimum −0.18 dB insertion loss and better than −21 dB reflection coefficient at 22 GHz frequency. Electromechanical characterization reports an actuation voltage of 14.6 V, mechanical vibration frequency of 2.5 MHz and a switching time of 620 ns respectively. Demonstrations showing complete realization of 180° phase shifter (4 mm × 1 mm) employing a cascaded arrangement of six similar 30° unit cells are also included in this paper. 相似文献