直流电桥法测量电缆故障点的距离

迅速、准确地探测故障点的位置对保证故障电缆的及时修复有着重要意义。介绍了电缆故障的性质和直流电桥法测量电缆故障点距离的原理，着重阐述了几种常用的电缆接地故障的测量方法，并提出在实际生产、施工中，应根据具体情况选取合理的仪器及测量方法，迅速、准确地探测故障点的位置，以保证故障电缆的及时修复。     

中国石化集团公司石油勘探开发国际合作的初步构想

在分析中国石化集团进行国际合作必要性的基础上,提出“引进来”和“走出去”是石化集团公司石油国际合作应采取的两种基本方式,并提出继续加强国内风险勘探和提高采收率的对外合作以及积极稳妥开展国际石油勘探开发合作业务的初步设想。     

纳米材料在提高采收率中的研究进展?

近年来，纳米材料因其有吸引力的物化特性已在生物医药、电子储能、保护涂层等领域发挥重要作用。随着石油资源的需求不断增加和开采难度提高，石油勘探和提高石油采收率技术需要不断创新，以满足未来对碳氢燃料的需求。将功能化的纳米材料与提高采收率技术结合，可以改善驱替剂的流变性能，改变储层岩石的润湿性、降低油水界面张力、提高原油的流动性等，进一步提高原油采收率，为油田的有效、可持续开发提供新的技术手段。本文首先综述了当前在提高采收率领域中的应用较多的几类纳米材料；之后，对纳米材料在提高采收率中的作用机理做了总结；最后，讨论了纳米材料在提高采收率技术中存在的问题，并对其发展趋势进行了展望。     

国际石油市场能否走出"供应担忧"和高油价的困扰--2005年国际石油市场述评及2006年展望

国际油价已持续3年居高不下，并屡创新高。世界石油需求高度增长和石油增产余力不足引发的供需关系紧张、产-消关系严重失衡、投机炒作猖獗、石油价格长期居高不下，使国际石油市场身陷“安全困境”。今后的2—3年内，影响国际石油市场的基本要素不会有多大改善，市场仍将处在剧烈动荡、油价续高的困扰之下。寻求“石油供应安全”已成为世界各国促进经济发展的共识和基本诉求。     

Synthesis, characterization and thermal properties of soluble aromatic poly(amide imide)s

Novel diamines such as N,N′-bis(aminoaryl)terephthalamido-2-carboxylic acids (BATCA), which contain primary amine, amide and carboxylic acid groups and are soluble in dilute aqueous NaOH solution, were synthesized by reacting aromatic diamines with trimellitic anhydride chloride in dimethylformamide. Poly(amide imide)s containing 3:1 ratio of amide:imide groups in the polymer chain were prepared by low temperature solution polymerization of BATCAs with isophthaloyl chloride or terephthaloyl chloride in dimethylformamide at 5-10 °C to form poly(amide amic acid)s, and followed by treating with a mixture of triethylamine and acetic anhydride. The PAIs were soluble in polar aprotic solvents like dimethylformamide, dimethylacetamide, dimethylsulphoxide and N-methylpyrrolidone, and have inherent viscosities in the range of 0.30-0.66 dL/g. The PAIs were characterized by IR, ¹H NMR and ¹³C NMR techniques. Thermogravimetric analysis (TGA) has shown that the initial decomposition temperatures of the polymers are in the range of 250-440 °C, depending upon the structures of diamine and diacid chloride. The glass transition temperatures of the PAIs are in the range of 128-320 °C. The IDT and T_g values of the polymers containing terephthaloyl unit are higher by about 20-40 °C than those of the polymers with isophthaloyl unit. BATCA could be utilized for the preparation of thin film composite membranes having PAA/PAI barrier layer on PES by in situ interfacial polymerization with IPC/TPC/TMC.     

Phase inversion and its effect on the properties of polyester polyurethane cationomers

Polyester polyurethane cationomers are prepared using polyester polyol of molecular weight 2000 as soft segments, N-methyl diethanolamine as chain extender, glycolic acid as quaternization agent, methyl ethyl ketone as solvent, and 4,4'-diphenylenemethylene diisocyanate (MDI) as diisocyanate. Properties of the films cast from solutions and emulsions are studied by infrared spectroscopy, dynamic mechanical analysis, thermogravimetric analysis, differential scanning calorimetry, and tensile-elongation testing. Ionization can cause phase separation and produces increased cohesion in the hard domains. The dispersion process can be divided into three stages involving a separation of hard segment aggregates due to adsorption of water on their surface, water entering into hard segment microionic lattics, and finally a rearrangement of agglomerates to form microspheres. The dispersion can disrupt the order in the hard domains and an increased phase separation.     

我国橡胶助剂工业的现状及前景

介绍了我国橡胶助剂工业的历史和现状，分析了存在的问题及发展机遇，并对我国橡胶助剂工业的发展提出建议。     

A growth mark method for studying growth mechanism of carbon nanotube arrays

A novel and simple growth mark method was developed to make marks during the growth process of carbon nanotube arrays. These marks can be read out under scanning electron microscope or optical microscope. Based on this method, the growth rates at different temperatures and under different acetylene partial pressures were measured, from which the activation energy and the order of reaction were determined. Based on our experimental results, the growth of carbon nanotube arrays in our experimental condition could not be diffusion-limited. The measured activation energy could possibly be attributed to the heterogeneous decomposition of acetylene over the catalyst particle. Furthermore the marked array with special segmental structure may be found some applications in the future.     

Synthesis and water absorbency of crosslinked superabsorbent polymers

A series of novel copolymer superabsorbents based on monomer acrylamide (AM), potassium methacrylate (KMA), and 2‐hydroxyethyl methacrylate (HEMA) were prepared by copolymerization using ammonium persulfate (APS) as an initiator and N,N‐methylenebisacrylamide (MBA) as a crosslinking agent. The synthetic variables (the monomer concentration, crosslinker concentration, and initiator concentration) were also studied. The experimental results of superabsorbent polymers (SAPs) show a better absorbency in both water and NaCl solutions. The copolymers were characterized by IR spectroscopy. The water retention in the soil was enhanced using the above superabsorbents. The use of SAPs for the growth of groundnut plants was also investigated. SAPs can be considered for water‐managing materials for agriculture and horticulture purposes in desert and drought‐prone areas. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1795–1801, 2002     

Review of Operating Experience Of Ozone Systems In Municipal Plants In The United States

The treatment chemical ozone has now been successfully used in the United States in municipal water and wastewater plants for many years. To insure continuous, successful operations of these applications, operating obstacles had to be dealt with and overcome.

In this paper, examples of field operating problems and their solutions are described. The experiences at specific municipal water and wastewater installations are reviewed in detail. Discussed for each example are : the background and effects of the problem, the problem-solving process, and the eventual resolution of the problem. The examples include simple unit operations to entire processes.

By observing the ozone installation's operation several years after start-up, the design of future ozone systems can be improved and operating problems minimized.