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951.
Yonghong Zhao Haihua Liang Jiefan Huang Jinda Geng Ren Wang 《Pure and Applied Geophysics》1995,145(3-4):759-773
Uniaxial compression tests on marble plates containing two prefabricateden echelon fractures were performed in this study. Photographs showing the typical characteristics of subcrack development were taken under direct scanning electron microscope (SEM) observation during the test. From these photographs, the effects of the lengthL of a single fracture, the separation distanced and overlapping proportiona/L between two prefabricateden echelon fractures on the development of subcracks were analyzed. The results show that the interaction betweenen echelon fractures strengthened with decreasingd. FordL, there was little interaction and the development of subcracks near one of theen echelon fractures was unaffected by the existence of the other. Whereas ford, the number of subcracks in the area intermediate betweenen echelon fractures tended to increase with increasinga and decreasingd. In order to ascertain whether the experiment can furnish some implications for research on earthquake prediction and neotectonic activity, the test results were compared with the spatial-temporal development of foreshocks and ground-water anomalies before the 1975 Haicheng earthquake and the structural framework of the Ganzi pull-apart basin. The results of the comparison are encouraging. According to the similarity between the test results in the laboratory and the natural phenomena in the field, the fault on which the Haicheng earthquake would occur, could be inferred immediately from the relative geometry of the two sub-parallel active faults in the area. Thus, it is considered that the test results would advance our understanding of the process of neotectonic activities and give us inspiration for earthquake prediction. 相似文献
952.
The spatial structure and temporal variations of the stationary wave anomalies in the uppertroposphere during the Northern Hemisphere winter are studied with the ECMWF data of 1980—1988 and PCA(principal component analysis)method.The vorticity source anomalies of the mainteleconnection patterns are analyzed,and their roles in the maintenance of the stationary waveanomaly teleconnection patterns are investigated with the harotropic model.The results show thatthe anomalies of transient vorticity flux convergences tend to cancel the anomaly of vorticitysources generated by divergent winds.The stationary wave anomaly patterns caused by divergentwind anomalies only are very different from observations.However,if the anomalous transientvorticity flux convergences are also included in the vorticity sources,the simulated patterns will begreatly improved. 相似文献
953.
通过对太行山中段区域地质,遥感地质,地球物理及地球化学特征的系统研究,总结出在本区寻找岩浆－热液型,剪切带型、微细浸染型金矿床的综合信息模式,以便为该区广泛地开展地质普查工作提供可靠依据。 相似文献
954.
Geng Wu Cheng Feng Xie Qiang Zou Xiaoli He Weihong Wang Zhaozheng Shu Yeqiang Chen Gengxin Liu Danian Ye Dong Wang Ruiwen Liu Chuanyu 《中国海洋湖沼学报》2020,38(6):1729-1745
Journal of Oceanology and Limnology - An ensemble-based method for the observation system simulation experiment (OSSE) is employed to design optimal observation stations and assess the present... 相似文献
955.
956.
957.
Introduction The degree of earth-resistivity anisotropy was described (MAO, et al, 1995, 1998) as follows: S=|1\nn∑I=1(ρSN\ρEW)I|-1|×103 n=6(1) whereρNS and ρEW are monthly mean values of earth resistivity in the direction of NS and EW, respectively, S is the half-year value. Equation (1) shows that if ρNS=ρEW, then S =0 and the electrical property of medium is isotropic; if ρNS≠ρEW, then S≠0 and the electrical property of medium is anisotropic. When S increases, the anisotropy of electrical property of medium is enhanced. Because the rightside of equation (1) is absolute value and the possibility ofρNS＞ρEW and ρNS＜ρEW can be different at different stations, the increase or decrease of S cannot reflect the relative changes between ρNS and ρEW. FENG, et al (2000) defined S as follows: 相似文献
958.
根据日立835—50型氨基酸自动分析仪生理体液分析法，以及同型胱氨酸的生理特性，建立测定同型胱氨酸的150min短程序法。经过精密度和准确度试验，重视性好，变异系数小。当同型胱氨酸浓度为4×10－5mol／L时，峰位置和峰面积的变异系数（CV值）分别为0．20％和1．98％（n＝10），明显低于规定技术指标（1％和2．5％）。对1、2、4（×10－4mol／L）浓度的同型胱氨酸加标回收试验，回收率为叶．33～106．67％（n＝9）。本法与原法同时测定大鼠及人体血浆的同型胱氨酸的含量结果基本一致。表明本方法准确、可靠、快速、简便，适用于高脂血症、动脉粥样硬化以及血栓等血浆中同型胱氨酸的测定。本方法样品处理采用任其与空气接触，使血浆中同半型胱氨酸氧化为同型胱氨酸，测定其总同型胱氨酸含量。 相似文献
959.
960.
海洋经济贝类育种研究进展 总被引：6，自引：2，他引：6
本文简要回顾了近些年来海洋经济贝类育种现状 ,综述了传统的杂交育种和各种现代生物技术如多倍体、转基因和分子标记技术在贝类育种中所取得的成就 ,特别是近年来分子标记技术应用于贝类杂种优势预测 ,群体遗传结构分析和标记辅助选择等。为新品种的培育提供了高效而可靠的手段。该技术的应用可望在较短的时间内改变目前海洋贝类品种培育的落后局面 相似文献