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101.
S. T. G. Raghu Kanth Konjengbam Darunkumar Singh Kumar Pallav 《Pure and Applied Geophysics》2009,166(4):641-672
In this article, the spatial variation of ground motion in Imphal City has been estimated by the finite-fault seismological
model coupled with site response analysis. The important seismic sources around Imphal City have been identified from the
fault map and past seismicity data. The rock level acceleration time histories at Imphal City for the 1869 Cachar (Mw 7.5) earthquake and a hypothetical Mw 8.1 event in the Indo-Burma subduction zone have been estimated by a stochastic finite-fault model. Soil investigation data
of 122 boreholes have been collected from several construction projects in Imphal City. Site response analysis has been carried
out and the surface level ground motion has been determined for Imphal City for these two earthquake events. The results are
presented in the form of peak ground acceleration (PGA) contour map. From the present study it has been ascertained that the
maximum amplification for PGA over Imphal City is as high as 2.5. The obtained contour maps can serve as guidelines for identifying
vulnerable areas and disaster mitigation in Imphal City. 相似文献
102.
Omid Sayar Iman Jabbari Zahir Abadi Omid Sadeghi Hamid Reza Lotfi Zadeh Zhad Najmeh Tavassoli 《洁净——土壤、空气、水》2012,40(3):272-277
Nano‐alumina modified by 9‐aminoacridine was used as a sorbent for separation and determination of dichromate ions from water. Statistical method, based on surface response design, has been used for the optimization of dichromate ions elution from 9‐aminoacridine nano‐alumina. The adsorbed dichromate ions were found to be eluted quantitatively with 0.8 mol L?1 KCl in 1.6 mol L?1 NaOH which optimized by response surface design. Under optimum conditions, the accuracy, precision (relative standard deviation, RSD%) and R‐square of the method were calculated as >98, <3, and >94%, respectively. Remarkable agreement between experimental and theoretical data was confirmed the predicted assumption. The method was applied to the simultaneous determination of dichromate in natural and industrial water samples. We also examined the retention of dichromate anions in the presence of Cl?, , and anions at pH 3. 相似文献
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基于1980—2014年的哈德莱中心海冰及海温的月平均SST资料,美国联合台风警报中心(JTWC)的best-track资料以及NCEP/NCAR再分析月平均资料,利用广义平衡反馈方法(GEFA)研究南印度洋热带气旋(TC)生成频数对海表温度异常的响应特征。研究表明:(1)南印度TC生成频数对北太平洋第一模态(NP1)和热带大西洋第二模态(TA2)有显著响应,分别通过了置信度为99%和96%的Monte-Carlo检验,对应的响应振幅分别为0.67和0.49。(2)局地环境要素对关键SSTA模的GEFA响应结果显示:当NP1出现类似于太平洋年代际振荡(PDO)的正位相时,850 h Pa相对涡度在15°S附近的印度洋海域上都有一个自西向东的显著正响应带,垂直风切变在马达加斯加以东的大部分海域都表现为显著的负响应,600 h Pa相对湿度在马达加斯加以东的部分海域表现为显著的正响应;当TA2对应的时间系数为正异常时,850 h Pa相对涡度和600 h Pa相对湿度在澳大利亚的西北部印度洋海域表现为显著的正响应,垂直风切变在澳大利亚的西北部印度洋海域表现为显著的负响应。 相似文献
106.
The pollution of underground and surface water streams is a tremendous environmental problem. Adsorption, in which activated carbon (AC) is used as an adsorbent, is one of efficient procedures to remove organic and inorganic pollutants from industrial wastewaters. Activated carbon fiber (ACF), a newly developed form of AC, has high adsorption rate and surface area and can be used for the treatment of industrial wastewaters. In this work, ACF was prepared by physicochemical activation method from kenaf and we studied its ability in the treatment of indigo‐containing wastewater produced from a dying factory. The filtered wastewater was treated via adsorption by ACF, and response surface experimental design method was used to study the effect of ACF dosage, contact time, temperature, and pH of the wastewater on the removal process. ACF dosage of 0.256 g, temperature of 12.5°C, pH 8.5, and contact time of 125 min were optimum treatment conditions. The adsorption process obeys pseudo‐second‐order kinetic and Freundlich isotherm models. 相似文献
107.
新甘交界红柳河地区早二叠世火山作用的环境响应 总被引:1,自引:0,他引:1
新甘交界红柳河地区早二叠世玄武岩与灰岩互层,玄武岩局部发育为枕状,枕间充填灰岩。通过对剖面碳酸盐岩样品的全岩无机碳氧同位素研究发现,与玄武岩互层的层状灰岩的δ~(13)C 和δ~(18)O 平均值分别为3.2‰和-14.2‰,枕状玄武岩间的块状灰岩的δ~(13)C 和δ~(18)O 的平均值分别为-0.7‰和-18.2‰,即碳酸盐岩的碳氧同位素组成在火山快速爆发时期相对于火山活动间隙时期明显偏负。通过对层状灰岩和枕间灰岩碳氧同位素研究发现,海盆火山作用是环境变化的主要控制因素。 相似文献
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许多前陆盆地同时存在着下部的裂陷正断裂和上部的造山期的挠曲正断裂。作用在均质不分层和非均质分层板块中的挠曲正断裂具有不同的外观形态和形变的空间协调机制,前者断面陡直、贯穿深远;后者则呈坡坪式形态。裂陷正断裂和挠曲正断裂具有3种相互作用方式、差异甚殊的断裂总体形态和中性面分布位置不同的应力体制。Ⅰ类,挠曲正断裂局限在陆缘期或坳陷期层序中;Ⅱ类,裂陷期正断裂断至断陷期层序,且以裂陷正断裂为基础而存在,二者构成完整而独特的断裂组合;Ⅲ类,挠曲正断裂亦断穿至断陷期层序,但和裂陷正断裂并不存在直接关系。这三类关系对孔隙—裂缝网络体具有不同的影响,并和应力体制一道,对流体尤其是烃类的作用过程有差异很大的影响。地层在跨越同生正断裂和挠曲正断裂时所发生的厚度的变化,起因于二者在物源方向上的完全不同。 相似文献
110.