钢塔架设计探讨

根据石油天然气工业中排气筒和火炬设计的特点，为了更好、更准确进行塔架设计。介绍了塔架设计中塔架结构几何尺寸和杆件截面的初选方法和经验数据；塔架结构受风荷载整体计算时体型系数的探讨；塔架基础在软土地基或基岩特殊条件下的处理方法。     

储层应力敏感性影响因素研究

全面分析储层应力敏感性产生的机理认为，外部因素的改变会引起储层产生应力敏感性．而储层岩石物性等内部因素对应力敏感性的强弱起决定性作用。室内岩心应力敏感性评价时．仪器与设备的精度、加载与卸载方式、实验用流体类型以及各种人为因素等都会对评价结果产生影响，其中岩心密封套在高压、高温条件下的密闭性会对实验结果产生较大影响。所以储层应力敏感性不应该从孔隙度和渗透率的高低进行简单评价，中、高渗储层和低渗储层在生产过程也都可能表现出较强的应力敏感性现象。     

溶剂脱沥青组合工艺生产重交通道路沥青

中国石化荆门分公司以江汉-阿曼混合原油和江汉-鲁宁混合原油为原料,分别采用减压蒸馏—丙烷脱沥青和减压蒸馏—添加催化裂化油浆—丙烷脱沥青工艺,生产出符合SH 0522—2000的100号道路沥青。结果表明,江汉-阿曼混合原油减压渣油中掺兑质量分数为30%的催化裂化油浆后,脱油沥青的各项性能均满足AH-70或AH-90重交通道路沥青的要求,而且薄膜烘箱试验表明,试样延度超过标准要求。     

五种恒虚警方法性能分析

比较了五种恒虚警方法在各种杂波背景下的检测性能,得出CMLD-CFAR是工程上可以实现且检测性能比较好的一种恒虚警处理方法.     

动感像素全息母版图案的设计制作研究

本文介绍了一种新颖的数码像素全息高速拍摄装置来实现全息母版的制作。提出和介绍了运用Photoshop软件一些特殊的图像处理功能设计制作动感像素全息图的方法,并结合多种防伪技术,使产生的图案具有不可仿制的图形畸变特点,并列举了设计实例。     

On the Feasibility of Growing Pb[(Zn1/3Nb2/3)0.91Ti0.09]O3 Single Crystals

Pb[(Zn_1/3Nb_2/3)_0.91Ti_0.09]O₃ (PZNT91/9) single crystals were grown by two methods: from solution using PbO as a self‐fluxing agent (SC method) and directly from the melt without fluxing (MC method). In both growth methods, an allomeric Pb[(Mg_1/3‐Nb_2/3)_0.69Ti_0.31]O₃ (PMNT69/31) single crystal was used as a seed. X‐ray diffraction patterns of ground crystals showed that phase‐pure perovskite PZNT91/9 single crystals were successfully fabricated by the above two methods. The composition of the crystals obtained by both the SC and MC methods was analyzed using X‐ray fluorescence, which confirmed that the crystal composition is close to the nominal value, although volatilization of PbO and segregation during crystal growth are inevitable. The MC PZNT91/9 crystals exhibit excellent piezoelectric properties, with the piezoelectric constant, d₃₃, in the range of 1800–2200 pC N^–1. This value is comparable to that of the SC crystals. However, the MC crystals show an abnormal dielectric behavior. In contrast with the SC crystals, in the MC crystals a much broader dielectric peak appears in the dielectric response curves, accompanied by a much lower peak temperature of around 105 °C. Furthermore, frequency dispersion is apparent over a much wider temperature range (even more apparent than in pure relaxors), where a large, i.e., about 70 °C, full width at half maximum (FWHM) for the dielectric peaks is observed in the dielectric response. It is speculated that such an unusual phenomenon correlates with defects, microinhomogeneities, and polar regions in the as‐grown MC crystals. The origins of this abnormality have not been interpreted in detail until now. However, optical observation of the domain structure confirms that both the SC and MC crystals possess complex structural states.     

Formation and inhibition of free radicals in electrically stressed and aged insulating polymers

Previous work has shown that prebreakdown, electrical aging, and breakdown phenomena are directly associated with charge carriers injected from electrical contacts and their subsequent dissociative trapping and recombination. In addition, the energy released from each trapping or recombination event is dissipated in the breaking of the bonds of macromolecules, thus forming free radicals and new traps in the electrically stressed insulating polymers, as predicted by Kao's model. It is this gradual degradation process that leads to electrical aging and destructive breakdown. New experimental results are presented to confirm previous findings and a new approach to inhibit the degradation process by the incorporation of suitable dopants into the polymer. The concentration of free radicals in the polymer increases with an increasing electric field at a fixed stress time of 250 h and with increasing stress time at a fixed electric field of 833 kV cm^?1. The concentration of free radicals is directly related to the concentration of new traps created by stress. However, when suitable dopants are incorporated, the initiation voltage for the occurrence of electrical treeing and the breakdown strength are both increased. The dopants tend to create shallow traps and have little effect on the deep trap concentration. This implies that the dopants act as free‐radical scavengers that tend to satisfy the unpaired electrons of the broken bonds, which create new acceptor‐like electron traps and new shallow traps. By doing so, the shallow traps screen the deep traps, thereby reducing the energy released during trapping and recombination and the probability of breaking the macromolecular bonds and causing structural degradation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3416–3425, 2003     

面积坐标法构造含转角自由度的四结点膜元

以四边形面积坐标作为工具,构造了两个含转角自由度的广义协调四边形单元AQ4和lAQ4。它们通过强式分片检验,与同类单元相比,具有很高的计算精度,能消除梯形闭锁现象,有很强的抗网格畸变的能力。     

Nd3+:Y0.5Gd0.5VO4晶体生长和基本特性

Nd^3 :Y0.5Gd0.5VO4晶体作为一种新的激光材料，可以用中频感应加热提拉法生长。X射线粉末衍射分析表明它的结构与Nd^3 :YVO4晶体结构相同，它的晶格常数介于YVO4和NdVO4晶格常数之间。用ICP光谱法测定晶体中Nd^3 含量为0．8at％，分凝系数为0．8，与Nd^3 :GdVO4晶体中Nd^3 的分凝系数0．78相当；用称重法测定其密度为5．00g／cm^3；用稳态纵向热流法测出其室温热导率为12．5W／mK。实验表明Nd^3 :Y0.5Gd0.5VO4晶体有希望作为高功率ID泵浦激光晶体材料。     

Study of Disk-Loaded Waveguide Filled with Plasma

Recently disk-loaded waveguide has been widely used in high-power traveling wave tubes (HPTWT). It has been shown in many experiments that the interaction efficiency and output power can be increased greatly by injecting plasma into the vacuum microwave device. Using field analysis, the dispersion characteristics and the interaction impedance of the disk-loaded waveguide filled with plasma are analyzed in a strong longitudinal magnetic field. In conclusion, the frequency of the TM₀₁ mode increases as the density of the plasma increases. It also can be found when the plasma density increases to a large scale, the TM₀₁ mode of the disk-loaded waveguide overlaps the TG mode, these two modes couple each other and form the new hybrid modes.