Pressure Behavior for Spherical Flow in a Reservoir of Non-Newtonian Power-Law Fluids

The pressure variations during polymer flooding of oil reservoirs for oil recovery projects can be used to analyze the flow in the reservoir which is especially useful for the partially perforated reservoirs. This paper presents a relationship between the viscosity and the shear rate which is similar to forms developed for radial flow (Odeh, A. S., Yang, H. T. ([1979]). SPEJ. AIME (Jun.) 155). The power-law viscosity model is used to give the variation of the fluid viscosity with the spherical radius for a mathematical model of unsteady spherical flow for non-Newtonian fluids with wellbore storage and skin. An analytical solution for the wellbore pressure responses derived in Laplace space is used to analyze the behavior characteristics at early and later times to interpret the well-test parameters. The pressure variations are similar to those for a Newtonian fluid at the early times, but at later times, the variation of the viscosity with the power-law exponent is important, so the pressure response differs from that for a Newtonian fluid. The solution has significance for interpreting well test parameters for non-Newtonian spherical flow.     

Dynamic Analysis of Truss‐Beam System

As the manned exploration of space continues, many complex structural components are being developed to construct the orbital platforms that will be used to house communication hardware, personnel, and manufacturing complexes. These components are extremely flexible and complex in their behavior. There is a need for a simple method for determining the dynamic characteristics of these space structures with a minimum of effort. A mathematical model of one of these structural elements, an articulating truss beam, has been developed to predict its dynamic response. Assumptions of the force interaction between the beam elements and the joints have been made for using this model. Algorithms are provided to determine the flexibility matrix of the truss beam for use in the equation of motion. The natural frequencies obtained from using this method are compared with those obtained by the finite element method. An experimental procedure is planned to validate the results from the theoretical method.     

降凝剂对高蜡稠油的改性效果及机理研究

实验研究了工业品原油降凝剂WHP改善含蜡56.9%、其中96.6%为正构烷烃的胜利郑王庄稠油流动性的效果。WHP含乙烯/醋酸乙烯/乙烯醇嵌段聚醚三元共聚物30%-35%。在60℃将WHP加入稠油中,测定其凝点和32℃、0-42.6 s^-1范围5个剪切速率下的黏度,均随WHP加量的增加（50-300 mg/L）而降低,200 mg/L为最佳加量,在该加量下0.32 s^-1黏度由34.16 Pa·s降至79.2 mPa·s,凝点（℃）、屈服值（Pa）、稠度系数（Pa·s^n）分别由49.0、32.42、31.57降至39.5、0.1297、0.02142,流型指数由0.1176升至0.9790。由黏温曲线求出,加入200mg/L WHP使该稠油析蜡点由65℃降至58℃,反常点由70℃降至50℃。根据空白和加剂原油扫描电镜照片显示的蜡晶形态,利用共晶机理分析讨论了WHP这种高分子表面活性剂的降凝、降黏、改善流动性的作用。图3表3参5。     

一种高效的图像细化算法在焊缝跟踪中的应用

针对焊缝跟踪图像处理的特点，研究了二值化后的图像如何进一步细化的方法；采用先对焊缝的边缘进行提取，然后从垂直于焊缝的方向进行扫描的方法，取两条边缘的中点，即是焊缝的骨架；结果表明：此算法能准确地对一幅二值图细化，满足焊缝跟踪中图像处理的要求；这种算法的突出特点是计算量小，处理速度快，非常适合于焊缝的实时处理跟踪，而且不用改写算法，既适合于黑色背景白色图像，也适合于白色背景黑色图像.本算法通过推导得到四条处理准则，在遵循这几条处理准则的基础上逐点扫描图像，按照准则来确定目标点的删除与保留，达到细化的最终目的.     

图像处理中自适应数学形态学的研究

实际图像处理中当视场的变化引起目标变形时,固定大小的形态学算子很难达到较好的处理效果。研究了利用距离变换自适应地调整结构元大小的方法,即根据图像的不同位置来调整结构元素的大小,从而实现图像的形态学运算,并由此推导出了快速计算方法,最后测试了这种新算法的有效性。实验结果表明,该算法取得了较为理想的效果。     

低碳微合金钢中的晶内铁素体及组织控制

回顾和评述了晶内铁素体的发现、发展及其与组织控制的关系.介绍了晶内铁素体的形核机制和影响晶内铁素体形成的因素,讨论了晶内铁素体的三维形态和长大动力学,并从以上几方面分析了晶内铁素体对低碳微合金钢组织细化的重要作用和影响.     

复合聚合物微粒乳液的制备与应用

对种子乳液聚合中加料方式、单体亲水性、引发剂等因素对复合微粒聚合物形成的影响作了介绍 ,总结了聚合物微粒形态预测的热力学和动力学方法。同时 ,讨论了复合聚合物微粒设计的原理并评述了其应用情况     

Melting and crystallization behaviour of elastoplastic semicrystalline copolymers: poly(ether ester)

The melting and crystallization behaviour of an elastoplastic semi-crystalline poly(etherester) has been studied by differential scanning calorimetry. The shape of the melting endotherm is strongly dependent on heating rate and annealing time and results from the sum of simultaneous melting and crystallization phenomena. Samples prepared by different techniques, i.e. by solvent evaporation or by melt extrusion, behave very differently owing to specific crystal morphologies. By applying the Hoffman-Weeks plot, the equilibrium melting temperature has been extrapolated. The Avrami treatment allows the calculation of the index n and of the rate constant K from the isothermal kinetic data.     

用数理统计方法判定检测下限

该文介绍如何用数理统计方法判定检测下限。     

硅酸铋晶体的蚀像形貌

本文研究了提拉法生长的硅酸铋晶体(BSO)的蚀像形貌,比较了{100},{110},{211},{111}面族的腐蚀像特征和腐蚀速度,并用周期性键链(PBC)的形貌理论分析了腐蚀形貌。通过蚀像形貌特征便可方便地进行晶体定向,准确地确定各族晶面之间的相对位置和极轴的方向等。