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671.
郯庐活断层与1668年郯城8.5级地震灾害 总被引:13,自引:0,他引:13
郯庐断裂带的地震活动主要集中于中部的下辽河-莱州湾段和潍坊-嘉山段,各段在活断层和地震活动方面存在不同的表现。1668年地震发生于潍坊-嘉山段的中部,是全新世断层活动的结果。该地震产生了性重的人口损失和建筑物破坏,其地震灾害具有典型性。未来应注意渤海地区地震的群集型活动以及安丘地区和新沂-泗洪地区的强震活动。还应注意在新的经济条件下新的地震灾害内容和新的灾害类型。 相似文献
672.
研究区位于额尔古纳地块的额木尔山中间隆起带东部边缘塔河过渡带内,砂金资源极为丰富,成矿条件十分优越,具有良好的找矿远景.通过对区内地层、岩浆岩、构造、地球物理、地球化学、遥感等综合信息进行分析,初步总结了区内成矿规律,指出找矿的有利部位,并对区内找矿关键作了简单探讨,为区内下步找矿工作取得突破性进展提供了一定的思路. 相似文献
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674.
Recent Development in Simultaneous Multi-Element Determination of the Platinum Group Elements and Gold in Geological and Environmental Samples 总被引:1,自引:0,他引:1
In recent years, the modern methods of multi-element analysis of precious metals have attracted wide attention in scientific research and industry. The application and development in the decomposition of samples, separation and enrichment, and modern instrumental analysis of the platinum-group elements (PGEs) and gold in geological and environmental samples have been reviewed. Finally, the tendency of analysis of precious metals is also prospected. 相似文献
675.
This paper presents an effective optimization technique for the elastic and inelastic drift performance design of reinforced concrete buildings under response spectrum loading and pushover loading. Attempts have been made to develop an automatic optimal elastic and inelastic drift design of concrete framework structures. The entire optimization procedure can be divided into elastic design optimization and inelastic design optimization. Using the principle of virtual work, the elastic drift response generated by the response spectrum loading and the inelastic drift response produced by the non‐linear pushover loading can be explicitly expressed in terms of element sizing design variables. The optimization methodology for the solution of the explicit design problem of buildings is fundamentally based on the Optimality Criteria approach. One ten‐story, two‐bay building frame example is presented to illustrate the effectiveness and practicality of the proposed optimal design method. While rapid convergence in a few design cycles is found in the elastic optimization process, relatively slow but steady and smooth convergence of the optimal performance‐based design is found in the inelastic optimization process. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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678.
Barry J. Katz Christopher G.A. Harrison Eugene H. Man 《Earth and Planetary Science Letters》1979,44(2):279-286
The “second region” of the kinetic curve for the racemization (epimerization) of isoleucine in foraminifera is defined from previously published data corrected for the thermal history experienced by the samples. These kinetic parameters are applied to racemization data from Deep Sea Drilling Project Sites 332A and 333 from the Deep Drill Valley, Mid-Atlantic Ridge, and Site 148 from the Aves Ridge, in order to determine whether there are any observable effects due to the geothermal gradient. The data for Site 148 clearly show an increase of temperature with depth. The data for the two sites of the Mid-Atlantic Ridge do not show this clear relationship. When bottom water temperature variations are taken into consideration, the effects of the geothermal gradient become apparent. Since the degree of racemization is dependent upon both age and temperature, a knowledge of the age of a sample places constraints upon its thermal history, and hence on the heat flow at the location since deposition of the sample. The crude heat flow models thus developed are compatible with present geologic and geophysical information. It appears probable that detailed heat flow models may be developed by improving analytical precision. 相似文献
679.
Jeffrey L. Bada Ming-Yung Shou Eugene H. Man Roy A. Schroeder 《Earth and Planetary Science Letters》1978,41(1):67-76
The diagenesis of the hydroxy amino acids serine and threonine in foraminiferal tests has been investigated. The decomposition pathways of these amino acids are complex; the principal reactions appear to be dehydration, aldol cleavage and decarboxylation. Stereochemical studies indicate that the α-amino-n-butyric acid (ABA) detected in foraminiferal tests is the end product of threonine dehydration pathway. Decomposition of serine and threonine in foraminiferal tests from two well-dated Caribbean deep-sea cores, P6304-8 and -9, has been found to follow irreversible first-order kinetics. Three empirical equations were derived for the disappearance of serine and threonine and the appearance of ABA. These equations can be used as a new geochronological method for dating foraminiferal tests from other deep-sea sediments. Preliminary results suggest that ages deduced from the ABA kinetics equation are most reliable because “species effect” and contamination problems are not important for this nonbiological amino acid. Because of the variable serine and threonine contents of modern foraminiferal species, it is likely that the accurate age estimates can be obtained from the serine and threonine decomposition equations only if a homogeneous species assemblage or single species sample isolated from mixed natural assemblages is used. 相似文献
680.
SONG Tao SUN Man LIANG Yutian Soavapa NGAMPRAMUAN WUZHATI Yeerken ZHOU Keyang 《地理学报(英文版)》2021,31(5):664-680
The development of overseas industrial parks is a key component of the Belt and Road Initiative and a practical way of promoting inclusive globalization by introducing new forms of cooperation between China and the host countries.In this paper,the Thai-Chinese Rayong Industrial Zone(TCRIZ),and the China-Indonesia Economic and Trade Cooperation Zone(KITIC)are discussed in the context of the evolving development strategies and tra-jectories through three interrelated conceptual lenses-policy mobility,actor networks,and partnerships.The actor-network theory provides a lens to analyze how policy mobility and partnerships develop for two industrial zone case studies.The development,which involves a multi-scalar process,is shaped by the interactions among the national states,the regional governments and corporations against a background of globalization.Three types of trans-national actor partnership networks have been identified,namely,hierarchical partnership,spontaneous partnership,and hybrid partnership.A highlight of the study is the role that the partnerships play in the process of policy mobility when it comes to the overseas industrial zones.It is argued that the partnerships are the key to achieving technology transfer on a cross-national basis,and the effectiveness of the technology transfer is dependent on partner selection and the roles of the actors in policy mobility. 相似文献