改进的FD—TD法分析二维理想导体TM近区散射问题

本文针对一般ＦＤ－ＴＤ方法分析计算二维理想导体散射问题所遇到散射体边角处难以精确处理的缺点进行了改进。将边角处总场近似解析解直接引入ＦＤ－ＴＤ法差分公式，得到了有关修正系数，为了检验此方法的有效性，有无限长导体方柱为例分别用一般ＦＤ－ＴＤ法和本文的ＦＤ－ＴＤ方法进行了分析研究，并与ＭＯＭ法进行了比较，所得结果说明改进后的ＦＤ－ＴＤ方法对分析计算导体边角附近电流分布特性是较有效的。     

Microstructural transformations of heat affected zones in duplex steel welded joints

The influence of the welding thermal conditions exemplified by heat input and heat treatment after welding on the structure of the heat affected zone (HAZ) UNS S31803 has been analysed. The post weld treatment was used to create the precisely defined thermal conditions for the decomposition of primary phases in the HAZ, by a multi-layer welding thermal cycle stimulation. Detailed analyses of the microstructure and chemical composition of the phases in the different post welded conditions were performed by scanning electron microscopy (SEM) combined with energy dispersive spectrometry (EDS) and transmission electron microscopy (TEM). Three types of secondary precipitates have been observed: secondary austenite (γ₂), carbides: M₂₃C₆ and M₇C₃. The dependence of the secondary austenite volume fraction and morphology in the HAZ on thermal cycle have been interpreted. The eutectoid decomposition of the primary phases in the analysed thermal conditions was confirmed.     

箕状凹陷坡折带成因及对同生断层和沉积的控制,以南襄盆地南阳凹陷为例

坡折带是沉积地貌突变的古构造枢纽带。南襄盆地南阳凹陷南部控凹铲状正断层在非平面上滑动造成凹陷北部盖层缓坡弯折,构成盆内沉积区域的分界线,是同生断层集中发育和沉积相发生突变的地带。特定的坡折带类型揭示了同沉积断裂的活动和分布特征,制约着沉积物的分散过程和砂体堆积。在不同的盆地演化阶段,同生断层与沉积相带控制着不同圈闭类型的形成。      

Analysis of crack tip plasticity for microstructurally small cracks using crystal plasticity theory

Crack tip plastic zone sizes and crack tip opening displacements (CTOD) for stationary microstructurally small cracks are calculated using the finite element method. To simulate the plastic deformation occurring at the crack tip, a two-dimensional small strain constitutive relationship from single crystal plasticity theory is implemented in the finite element code ANSYS as a user-defined plasticity subroutine. Small cracks are modeled in both single grains and multiple grains, and different crystallographic conditions are considered. The computed plastic zone sizes and CTOD are compared with those found using conventional isotropic plasticity theory, and significant differences are observed.     

表外储油层酸化防膨剂的评价及效果分析

本文论述了采用不同防膨试验方法评价不同类型粘土防膨剂,并以回归曲线和价值工程分析防膨效果。由分子结构理论提出分子保护膜的防膨机理新观点,论述了酸液中添加具有多种功能的非离子型防膨剂QC—1可提高表外储层酸化与排酸效果。     

用屏蔽暂堵技术封堵水平井裂缝性漏层

克拉玛依油田HW702水平井的大斜度段和水平段,将穿越纵向裂缝发育的二叠系佳木河组储层。为安全钻进和保护油层,用超细碳酸钙和磺化沥青复配后加入复合离子钻井液中成屏蔽暂堵的堵漏钻井液。室内用岩心试验,屏蔽暂堵后渗透率可降为0,暂堵深度小于3cm,可用酸化和射孔解堵。现场使用效果也很好,使HW702水平井顺利完钻,并获得工业油气流。     

横波速度各向异性初步探讨：—多波勘探资料的应用

在纵波、SH 型横波资料处理和解释过程中,我们发现四川 HBC 地区地下介质普遍存在方向各向异性。当横波通过方向各向异性介质时,分裂成两个波:一个波的偏振方向与裂缝平行,叫快横波;另一个波的偏振方向与裂缝走向垂直,叫慢横波。采用相应的观测和处理方法,便可获得快横波和慢横波剖面。根据同一界面的快、慢横波的旅行时可以求得各向异性系数。同样,还可以利用 SH 波与转换波的速度比求取各向异性系数。各向异性系数的大小,反映了裂缝的发育程度。如果野外作了 X、Y 分量观测,室内又作了坐标旋转处理,那么,就可以进一步确定裂缝带的方向。如果未作上述工作,也可以根据构造线走向,大致确定裂缝带的发育方向。     

塔巴庙区块气层录井参数分析研究

塔巴庙区块气藏属于低压、低渗气藏,储集层物性差异大、含气级别高,但含气非均质性强,录井解释评价困难。针对这一问题,开展了综合判断储集层物性和含气性方面的研究,分别探讨了钻时与全烃、钻井液性能与全烃、钻井液粘度与全烃、气测显示与测井参数和烃组分与气显示之间的关系,分析了其相关性及其在塔巴庙区块气层解释评价中的意义及作用。通过相关性研究,不但摸索出定性解释评价气层的方法,同时为今后深入研究录井相关参数关系,探索其内在规律,为实现准确解释评价储集层奠定了基础。     

Visualization and quantification of the mechanical deformation induced by an electrical field in poly(ethylene naphthalene 2,6‐dicarboxylate) (PEN) films

An optical nondestructive strain measurement technique was performed to analyze the mechanical deformation induced by an electrical field within the insulating materials. Poly(ethylene naphthalene 2,6‐dicarboxylate) (PEN) films were then subjected to constant electrical fields right up to their electrical breakdown. The experimental technique made it possible to follow the various stages of the mechanical behavior of PEN in real time. The final breakdown occurred in the observation zone and the related mechanical deformation was captured. A “margarita” structure was observed with a hole at the center. The experimental results indicated that the level of the induced‐mechanical deformations depended on the local environment. We defined two different zones representing the inside and the outside of the damaged area. The induced‐deformations were larger in the damaged zone. It was also observed that deformations increased when the sample had a lower degree of crystallinity. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Antimicrobial finishing of regular and modified polyethylene terephthalate fabrics

An effective two-stage method has been developed for imparting antimicrobial properties to regular polyethylene terephthalate (R-PET), polyethylene glycol modified polyethylene terephthalate (PEG-M-PET), R-PET/Cotton blend (R-PET/C) and PEG-M-PET/Cotton blend (PEG-M-PET/C) fabrics. The method consists of partial hydrolysis of the fabrics to create carboxylic groups in PET macromolecules followed by subsequent reaction with dimethylalkylbenzyl ammonium chloride (DMABAC) under alkaline conditions. The reaction conditions such as pH, reaction temperature and time, carboxylic content, and DMABAC concentration were studied. Characterization of the finished fabrics was carried out through scanning electron microscopy (SEM) and Fourier transform infrared spectra (FTIR). All the modified PET fabrics showed excellent antibacterial activity towards Gram-positive (Bacillus mycoides), Gram-negative (Escherichia coli), and nonfilamentous fungus (Candida albicans). The achieved antimicrobial functions on the PET fabrics are durable in repeated laundering processes. Even after laundering 10 times the fabrics could still provide more than 85% of its antimicrobial activity against B. mycoides, E. coli, and C. albicans. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008