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171.
172.
强干扰区进行地球物理探测,尤其是电磁法勘探时,难以获得可靠的、高质量的原始数据;为取得良好的勘探效果,预处理的重要性更加凸显。通过对原始数据的呈现、分析,提出数据预处理的两套方案,并从理论和实际上证实了方案的可行性。最终结合勘探实例,对比两套数据预处理方案,优选全区视电阻率的方法对原始数据进行预处理,并对其预处理数据反演成图,取得了良好的应用效果。 相似文献
173.
The generation of air microbubbles in microfluidic systems or in capillaries could be of great interest for transportation (single cell analysis, organite transportation) or for liquid compartmentation. The physicochemical characterization of air bubbles and a better understanding of the process leading to bubble generation during electrophoresis is also interesting in a theoretical point of view. In this work, the generation of microbubbles on hydrophobic Glaco™ coated capillaries has been studied in water-based electrolyte. Air bubbles were generated at the detection window and the required experimental parameters for microbubbles generation have been identified. Generated bubbles migrated against the electroosmotic flow, as would do strongly negatively charged solutes, under constant electric field. They have been characterized in terms of dimensions, electrophoretic mobility, and apparent charge. 相似文献
174.
C. H. Patel A. B. Patel N. K. Bhatt P. N. Gajjar 《Physics and Chemistry of Liquids》2018,56(2):153-163
The calculations of electrical resistivity of Sn–Pb liquid metallic alloys/solutions are investigated by self-consistent approach. We employ modified empty-core pseudopotential to represent electron–ion interaction, while partial structure factors are calculated using Aschroft–Langreth scheme with hard sphere reference system. The potential parameters for elemental metals were optimised to structural data in our previous paper. Computed results for resistivity as a function of temperature and concentration are discussed with other such results. Overall good agreement confirms the applicability of the present model potential for computing the electrical properties, including thermal conductivity and thermoelectric power for liquid metallic alloys. 相似文献
175.
Micellar Exchange Kinetics of Quaternary Ammonium Type Gemini Surfactants Monitored by Nuclear Magnetic Resonance
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The dynamic NMR (DNMR) method was used to detect kinetic parameters of the molecular exchange process between monomers in bulk solution and those in the micelle for Gemini surfactants, 12-s-12 and 14-s-14(s=2, 3 and 4).The escape rate constant, k-, was derived based on the simplified equations of DNMR theory, and the apparent activation energy of escape, Ea-, was obtained based on the Arrhenius equation through temperature variation experiments.Results show that the orders of magnitude of k- for 14-s-14 and 12-s-12 are respectively 10 and 103 s-1, Ea- of 14-s-14 and 12-s-12 are respectively 54.04-73.64 and 33.42-47.09 kJ/mol.Furthermore, increases and Ea- decreases with the spacer length growing.In combination with the micro-polarity measurements, it was revealed that molecules of 14-s-14 and 12-s-12 have to experience conformation changes when escaping from the micelles.The two-step molecular exchange mechanism for Gemini surfactants was therefore supported. 相似文献
176.
采用电桥及X射线衍射线形分析法研究磁控溅射Cu/Ni多层膜(CLI及Ni单层厚度均为5nm)的室温电阻率及平均位错密度随对层(bilayer)层数的变化规律.结果表明,随层数增加,电阻率及平均位错密度减少;多层膜电阻率大于单层膜电阻率;单层膜电阻率大于同质块状体的电阻率.并对其微观机制进行分析. 相似文献
177.
通过大量的相似材料配比试验研究证明,在材料中加入一定浓度适量的Nacl溶液是实现覆岩破坏稳恒电场特征相似材料模拟的最佳方法。试验得出了相似材料电阻率与Nacl溶液浓度的关系。按照这一关系配制的相似材料模型的试验结果准确地反映了覆岩破坏稳恒电场的变化特征。 相似文献
178.
Guoqiang Li Wanqi Jie Hui Hua Zhi Gu 《Progress in Crystal Growth and Characterization of Materials》2003,46(3):85-104
The choice a suitable crystal growth method and a reasonable x value is of profound importance in the preparation of high quality Cd1−xZnxTe crystals for x-ray and gamma-ray detectors. The present paper reviews the evolution and development of Cd1−xZnxTe crystal growth for x-ray and gamma-ray detectors. At the same time, emphasis is put upon finding the relationship between the x value and the quality of the Cd1−xZnxTe. Three sets of Cd1−xZnxTe ingots with different x values, specifically 0.10, 0.15, and 0.20 were grown by the vertical Bridgman method (VBM) and characterized. Their x specification was then correlated with their dislocation densities, Te precipitates, inclusions, IR transmission, resistivities, and impurity concentrations, respectively. It was found that VBM Cd0.85Zn0.15Te as grown in this paper possessed the best choice of qualities with respect to defects and impurities. 相似文献
179.
针对现有导电模型很难描述骨架含导电矿物黄铁矿的岩石导电规律的难题,利用骨架完全由导电颗粒组成的人造岩样以及骨架部分由导电颗粒组成的天然和人造岩样的岩电实验数据,研究水电阻率和导电颗粒体积分数变化对岩石导电规律的影响,得出骨架导电纯岩石的地层因素与孔隙度及电阻增大系数与含水饱和度在双对数坐标上为非线性关系,随水电导率减小或导电颗粒体积分数增大,地层因素和电阻增大系数值降低。根据骨架导电纯岩石的组成,结合连通导电理论特点,将骨架导电纯岩石分为不导电骨架相、导电骨架相和自由流体相。基于连通导电方程只能描述单一导电相的两相混合介质导电规律而HB方程能描述两相均导电的混合介质导电规律的特点,基于连通导电理和HB方程建立骨架导电纯岩石电阻率模型。结果表明,骨架导电纯岩石电阻率模型预测的地层因素与孔隙度以及电阻增大系数与含水饱和度的理论关系与实验规律相符且模型满足物理约束,该模型能够描述骨架完全和部分由导电矿物组成的纯岩石的导电规律,可用于定量评价骨架导电低阻油层的饱和度。 相似文献
180.