Damage to urban buildings in zones of intensities Ⅷ and Ⅶ during the Wenchuan earthquake and discussion on some typical damages

The outline and typical characteristics of damages to building in Jiangyou city and Anxian county(intensity VⅢ), Mianyang city and Deyang city(intensity VII) are introduced in the paper.The damage ratios, based on the sample statistics of multi-story brick buildings together with multi-story brick buildings with RC frame at first story(BBF), are presented.Then some typical damages, such as horizontal cricks of brick masonry buildings, X-shaped cricks on the walls under windows, the damages to columns, beams...     

长江三角洲经济与社会可持续发展若干问题咨询综合报告

长江三角洲是我国最大的经济核心区,特别是邓小平同志多次视察上海并决定浦东开发开放以来,这一地区的经济建设取得了举世瞩目的发展。该地区虽仅占有全国１％的土地、６％的人口,但１９９６年所创产值却占国内生产总值的１５１％,相当于全国财政收入的１８７％。同时,该地区也已成为继珠江三角洲之后我国与世界各国经济往来最频繁的地区和海内外投资的新的热点。但是,长江三角洲在经济增长方式、产业结构与布局、农业持续发展、长江口整治与建设上海国际航运中心、环境保护等方面也存在不少亟待研究和解决的问题。受国家计委委托,中国科学院学部从１９９６年开始组织江、浙、沪地区的有关院士和专家,对长江三角洲地区的经济与社会可持续发展的几个重大问题进行了长达两年的调查研究,提出了《长江三角洲经济与社会可持续发展若干问题咨询综合报告》及４个专题报告。本刊摘要转发该综合报告,供国内地学界科技人员从事有关研究时参考。《报告》认为,长江三角洲应在我国率先实现现代化并带动长江沿江经济带和长江流域的发展。在现有经济支柱的基础上,进一步确立长江三角洲在长江流域乃至全国的经济主导地位,建设成为三大基地,发挥四大功能,提供五方面服务,即：成为我国进入世界市场、     

关于21世纪初期加快西北地区发展的若干建议

为了响应江泽民总书记提出的“要把加快大西北开发作为一个重大战略问题来实施”的号召,中国科学院地学部于1999年4月组成西北地区可持续发展研究组,组织10余位院士、专家在有关部门历年大量工作的基础上,综合分析已有的资料,对西北地区发展的相关问题进行了深入研讨,形成了“关于21世纪初期加快西北地区发展的若干建议”咨询报告。该建议可供有关部门在制定“十五”计划和2015年长期规划时参考,现全文刊出以飨读者。     

Physical Modeling and Parametric Study on Two-Degree-of-Freedom VIV of A Cylinder near Rigid Wall

Unlike most previous studies on the transverse vortex-induced vibration(VIV) of a cylinder mainly under the wallfree condition (Williamson & Govardhan,2004),this paper experimentally investigates the vortex-induced vibration of a cylinder with two degrees of freedom near a rigid wall exposed to steady flow.The amplitude and frequency responses of the cylinder are discussed.The lee wake flow patterns of the cylinder undergoing VIV were visualized by employing the hydrogen bubble technique.The effects of the gap-to-diameter ratio (e0/D) and the mass ratio on the vibration amplitude and frequency are analyzed.Comparisons of VIV response of the cylinder are made between one degree (only transverse) and two degrees of freedom (streamwise and transverse) and those between the present study and previous ones.The experimental observation indicates that there are two types of streamwise vibration,i.e.the first streamwise vibration (FSV) with small amplitude and the second streamwise vibration (SSV) which coexists with transverse vibration.The vortex shedding pattem for the FSV is approximately symmetric and that for the SSV is alternate.The first streamwise vibration tends to disappear with the decrease of e0/D.For the case of large gap-to-diameter ratios (e.g.e0/D = 0.54～1.58),the maximum amplitudes of the second streamwise vibration and transverse one increase with the increasing gapto-diameter ratio.But for the case of small gap-to-diameter ratios (e.g.e0/D = 0.16,0.23),the vibration amplitude of the cylinder increases slowly at the initial stage (i.e.at small reduced velocity V,),and across the maximum amplitude it decreases quickly at the last stage (i.e.at large Vr).Within the range ofthe examined small mass ratio (m＜4),both streamwise and transverse vibration amplitude of the cylinder decrease with the increase of mass ratio for the fixed value of V,.The vibration range (in terms of Vr ) tends to widen with the decrease of the mass ratio.In the second streamwise vibration region,the vibration frequency of the cylinder with a small mass ratio (e.g.mx = 1.44) undergoes a jump at a certain Vr,.The maximum amplitudes of the transverse vibration for two-degree-of-freedom case is larger than that for one-degree-of-freedom case,but the transverse vibration frequency of the cylinder with two degrees of freedom is lower than that with one degree of freedom (transverse).     

中天山地块南北两缘的韧性剪切带

本文详细描述了天山中段沿乌鲁木齐—库尔勒公路后峡—乌瓦门段的构造变形特点。综合室内外观察研究结果，在中天山地块南、北缘，及内部的乌拉斯台地区鉴别出三条规模较大的韧性剪切带：中天山北缘剪切带前人已有研究，出露宽达10km的右行斜冲剪切带，见大量糜棱岩、超糜棱岩；乌拉斯台剪切带中的糜棱岩宽超过200m，具有左行走滑运动特点；中天山地块南缘剪切带宽度达5km，内部发育大量闪长质糜棱岩、超糜棱岩，运动方式为左行斜冲。中天山块体南北两侧的脆性边界断层与糜棱岩带变形中心基本重合。这些剪切带具有相当大的走滑位移量，指示天山各地质单元间目前的空间关系可能是走滑拼接的结果。研究天山造山带内剪切带的展布、运动方式、总变形量，对于恢复各地质单元的初始位置、了解造山动力学过程具有重要意义。     

Notes on Extended-Range Atmospheric Prediction in the Northern Hemisphere Winter

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四川铜街子绿鳞石研究

本文利用X射线衍射仪、扫描电子显微镜等手段,研究了取自四川省铜街子某地凝灰岩和火山碎屑岩浅沼湖相堆积物夹层中的绿鳞石。对该矿物的化学组成进行的研究表明,它是一种比较典型的低镁型绿鳞石。     

2009年度国家自然科学基金项目指南(地球科学部分)

面上项目指南地球科学是人类认识地球的一门基础科学。它以地球系统及其组成部分为研究对象,探究发生在其中的各种现象、过程及过程之间的相互作用,以提高对地球的认识水平,并利用获取的知识为解决人类生存与可持续发展中的资源供给、环境保护、减轻灾害等重大问题提供科学依据     

典型强震动加速度仪一致性检验

针对两种典型强震动加速度仪,ETNA与MR2002,利用汶川地震强余震流动观测进行了两仪器的一致性检验.通过架设在同一仪器墩上的2种强震动加速度仪在5次余震事件中所获取加速度记录的波形、峰值、傅里叶振幅谱及反应谱的对比分析可知,ETNA仪器记录的峰值加速度与MR2002仪器记录的峰值加速度间的最大相对误差达23.6％,且南北向峰值加速度差异大于东西向和竖向,竖向明显小于两水平向;反应谱及傅里叶谱变化趋势基本相同,只是幅值存在些微差异,且竖向谱值相差最小,明显小于两水平向,反应谱最大相对误差近5％,相对于低频反应谱,高频反应谱差异较大;此外,亦存在两仪器记录时程曲线反向、记录时间长度不等、触发点不同等差异.经分析认为,这些差异主要是由于两种不同仪器性能上的微差异、仪器参数设置不同、以及触发滤波算法不同等因素引起的.