石油钻机提升系统穿绳方法研究

目前国内外钻机大绳一般采用顺穿法或花穿法。分析了2种穿绳方法的受力特点,大绳顺穿时游车的受力不平衡,会发生倾斜和摆动;采用大绳花穿方法,避免了游车的倾斜和摆动,但造成大绳入轮槽的倾角大,大绳易脱槽。顺穿法一般在电动钻机上采用,主要考虑到电控操作提升系统比较平稳;花穿法一般在机械钻机上使用,以受力平衡来缓解气控操作带来的冲击载荷的影响。为了克服这2种穿绳方法的不足,提出了两行双联滑轮组顺穿法和双联滑轮组顺穿法,可以提高安全性,减少磨损。     

Separating inviscid flows

Summary The separating flow of an inviscid fluid is not only a limit solution of the steady separating, laminar fluid flow at high values of the Reynolds number but it is also part of its structure (Smith [1], [2]). This work aims at reexamining the separating flow of inviscid fluid past a bluff body which is fixed in an otherwise uniform stream of fluid. For the purpose of this paper we will assume that the bluff body is a circular cylinder but the theory is applicable to bodies of any shape. It is further assumed that the fluid is in steady two-dimensional motion and is inviscid and of constant density. The flow structure is assumed to consist of a separated flow region, caviting flows in which there exists a free surface on which the pressure is constant, and a wake. A twin spiral vortex model is used in order to determine the shape of the free streamline. Based on the free streamline theory the problem reduces to solving a mixed boundary value problem and a Hilbert solution for the inverse problem in the auxiliary plane is obtained. When we consider the flow in the physical plane the problem is transformed into a direct problem in which the geometry of the solid body is given in advance. We assume that the separation is smooth and thus the curvature of the free streamline at the point of free detachment be equal to that of the body surface. A numerical method for solving the two-dimensional potential flows past arbitrarily shaped curved bluff bodies is developed.When the cavitation number is zero the angle of separation is approximately 55° and the computed results predict that the position of the separation point will move backward as the cavition number increases. The relationships between the drag coefficient, and the width and length of the cavity is determined and is found to be in very good agreement with the predictions of Smith [1].     

A Novel Athermal 40-Channel DWDM Multi/Demultiplexer Based on the Combination of AWGs and Interleaver

An athermal 40-channel dense wavelength-division-multiplexing multi/demultiplexer using a novel combination technology is proposed. It consists of one 1times4 100- to 400-GHz spacing interleaver filter and four sub-arrayed-waveguide gratings (AWGs). The temperature-dependent wavelength shift of the combined device is successfully suppressed to 0.058 nm in the -20degC to 70degC temperature range. Moreover, the combined device's adjacent crosstalk (typically -35 dB) is much better than conventional AWGs (typically -25 dB).     

China＇s Electric Power Reform：Different Economics and Challenges

China＇s electric power reform has followed the western reform format, however, it doest not seem to have endorsed the liberalization ideology underlying the reform model. This raises the concern of whether and how a competitive power market may be established and reform objectives reached. The new market competition model is easy to build in theory. The experience of many countries suggests that the market reform is extremely difficult because of the interruptions by different interest groups. To transform a centrally planned power sector into a competitive power market is a daunting task. Policy makers need to take into consideration the transitional nature of the economy and power industry as they implement the competitive power market model.     

Displacement Discontinuity Method for Fracture Mechanics Analysis of Reissner Plates: Static and Dynamic

This paper is concerned with the displacement discontinuity method applied to the shear deformable plates (Reissner’s and Mindlin’s theories) with cracks subjected to static and dynamic loads. Fundamental solutions of dislocation are derived using the Fourier transform method and the Laplace transformation technique. Boundary integral equations are presented in terms of rotations/displacement on the crack surfaces. The Chebyshev polynomials of the second kind are used to evaluate the integral equations with hypersingular kernels on the crack boundaries and determine the stress intensity factors at the crack tips. Comparisons are made with other numerical solutions to demonstrate the proposed method is accurate both for static and dynamic problems.     

中频反应溅射SiO2膜与直流溅射ITO膜的在线联镀

多数ITO透明导电玻璃生产线在实现SiO2膜与ITO膜在线联镀时，应用SiO2靶射频溅射沉积SiO2膜工艺和ITO靶直流溅射沉积ITO膜工艺，如果SiO2膜应用硅靶反应磁控溅射工艺，存在这种工艺是否可以与ITO靶直流溅射沉积ITO膜工艺在线联用以及如何实现联用的问题。作者对现有的生产线进行了改造设计、加工，做了大量实验、质谱分析和多项测试研究，成功地实现反应溅射SiO2膜与ITO膜在线联镀，做到SiO2镀膜室的工作状态的变化基本上不影响ITO镀膜室的工艺条件。     

关于最远点判定及直径的唯一性

给出了点到有界集最远点的一些必要或充分条件，然后对直径的唯一性也给出了一些判定条件。     

纳米超晶格热电材料的研究进展

随着热电材料制备技术和性能研究的发展，纳米超晶格热电薄膜已受到人们的关注，简要介绍了有关纳米超晶格热电材料的结构、热电机理及制作技术，并指出了存在的问题和可能的发展方向。     

省煤器管开裂原因分析

对省煤器开裂管进行了化学成分及宏、微观分析。分析结果表明，在高温高压条件下，在其焊缝溶合区出现粗大的魏氏组织，管材中的珠光体组织产生了不同程度的球化，而母材组织又存在严重的带状组织。在过热条件下熔合区极易出现裂纹，并由此快速扩展，造成省煤器管开裂。     

纳米NiO粉体的制备及其表征

采用溶胶转化－凝胶法制备了纳米级NiO粉体。Ni(OH)2粉体的TG－DSC分析表明：在升温速率为10℃/min的条件下，粉体在489K时开始显著分解，626K时分解完毕。X－射线衍射分析表明：分解产物为纯净的NiO2。NiO粉体的化学成分分析表明：其纯度高于国家标准。TEM电镜分析表明：NiO粉体呈单分散的球形或棒状颗粒。对NiO粉体的热敏性能有待进一步研究。