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21.
中国油田堵水技术综述   总被引:17,自引:0,他引:17  
刘翔鹗  李宇乡 《油田化学》1992,9(2):180-187
本文论述了我国油田堵水技术的发展及其在油田开发中的作用,总结和阐述了油井化学堵水技术和注水井吸水剖面调整技术的原理和效益,指明了实践证实的有成效的工艺方法和堵水技术发展方向。  相似文献   
22.
Provides the biography of Dante Cicchetti and announces that he has received the APA Award for Distinguished Senior Career Contributions to Psychology in the Public Interest (2004) for his seminal role in bridging theory, research, and practice by fostering the emergence and coalescence of the field of developmental psychopathology. A selected bibliography is also provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
The paper describes some geotechnical properties of the soft soils in Guangzhou College City, China, which are difficult to both sample and test. Laboratory and in situ tests were carried out to assess the physical and mechanical indices of the soils. The data were statistically analyzed and linear regression undertaken such that equations could be developed by which the geotechnical properties of the soft soils can be predicted. The statistical validity of the degree of correlation confirmed that using these equations, the mechanical indices can be estimated from physical indices determined by routine testing.   相似文献   
24.
25.
Electrokinetic remediation of soils contaminated with heavy metals   总被引:2,自引:0,他引:2  
This paper describes the results obtained from an electrokinetic treatment of a real soil polluted by lead acetate. Powdered soil samples were pressed with a consolidometer till 100 kPa to obtain cylindrical specimens with the same characteristics as a subsoil. Tests were carried out in a Perspex electrochemical cell where soil specimens were introduced with a hollow punch. A low intensity direct current was applied in order to remove contaminants, due to electrophoresis and electroosmosis phenomena. The water flow, conductivity, apparent electroosmotic coefficient, as well as other characteristic parameters, were measured throughout the test. The water content and degree of pore saturation were estimated at the beginning and end of the test. The soil slab was divided into four slices and the Pb concentration profile determined. The main factor governing the extraction of contaminant was found to be the pH in the acidic range. Indeed, under these conditions high removal efficiencies could be reached. These results could lead to the design of a new electrochemical treatment cell equipped with a cationic membrane to expand the region of favourable pH within the soil.  相似文献   
26.
介绍首钢2号高炉大修采用的新技术、开炉操作和投产以来的生产情况。  相似文献   
27.
对职业教育的大众性问题进行了论述、实证分析和理论、政策、改革等思考。  相似文献   
28.
An analytical method is presented for calculating the resonant frequency andQ-factor of a superconducting dielectric disk resonator operating in millimeter-wave regime with whispering-gallery mode. Resonant frequency shift due to the optical generation of quasi-particles in superconducting film is investigated as a function of photon flux. An optically tunable resonant frequency of about 500 MHz is estimated, and good agreement is found between numerical results and experimental ones.  相似文献   
29.
The condition of the surfaces is of crucial importance for the deuterium permeation through materials. In this work a study of the surface constants for the adsorption (σk1) and release (σk2) of deuterium under different surface conditions on the martensitic steel DIN 1.4914 (MANET) has been carried out. The growth of an oxide surface layer (Cr2O3) of about 25–30 nm in a MANET sample, heat treated in an oxidizing environment, compared to the bare MANET that have a ‘natural' oxide of about 5 nm has provoked a reduction of both the permeation rate and the recombination coefficient (about 3 orders of magnitude). In addition, the permeation governing process has changed from diffusion-limited to surface-limited. The measurements of the permeation rate of deuterium were performed by a gas-phase permeation technique over the temperature range 574–746 K and for deuterium driving pressures in the range from 3 to 105 Pa.  相似文献   
30.
文中结合垃圾焚烧发电厂烟气处理设计,介绍了干法烟气净化系统设计的主要技术要点及其效果,为垃圾焚烧发电厂烟气净化处理提供了设计的方向.  相似文献   
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