“全国第一次准晶态学术讨论会”简讯

目前,世界范围内正在兴起一个准晶态研究的热潮。在这样的背景下,由中国科学院北京电子显微镜和沈阳固体原子像两个开放实验室召开的全国第一次准晶态学术讨论会于1985年10月17日至19日在北京举行,到会的有正在从事和准备开展准晶态实验和理论研究的、分属五所高等院校和五个研究院所的科学工作者37人。     

晋江口海岸线变迁与泉州港的衰落

江河湖海转变为陆地和陆地转变为水域这种情况,自地球形成以来,就在不断地出现。在我国许多地方都可以看到海陆变迁的遗迹和某种变迁的过程,所以我国很早就产生“沧海桑田” 相互变化的思想,并非偶然。     

中国地质学会六十年史略

中国地质学会于1922年1月27日在北京成立以来,至今已整整六十年了。六十年来由于全体会员的辛勤努力,积极开展学术活动,对于现代地质科学在我国的发展,起着重要的促进作用;在国际地质科学界也享有一定的声誉。一、中国地质事业的萌芽和中国地质学会的成立     

云南澜沧-耿马Ms7.6地震的完全库仑破裂应力变化与后续地震的动态、静态应力触发

计算和研究了1988年云南澜沧-耿马Ms7.6地震产生的完全库仑破裂应力变化的时空演化图像, 对继澜沧地震13 min后发生的耿马M7.2地震的应力触发问题进行了分析, 同时也对澜沧-耿马地震后24 d内发生的Ms5.0~6.9后续强余震的应力触发问题进行了探讨. 结果显示, 澜沧地震断层破裂产生的完全库仑破裂应力变化空间分布图像具有很强的非对称性, 正值的动态和静态库仑破裂应力变化区域均具有与强余震分布位置吻合较好的现象. 耿马Ms7.2地震受到了澜沧Ms7.6地震产生动态和静态库仑破裂应力的触发作用; 绝大多数后续强余震受到了动、静态库仑破裂应力的综合触发作用.     

The Permo-Carboniferous Oslo Rift through six stages and 65 million years

The Oslo Rift is the northernmost part of the Rotliegendes basin system in Europe. The rift was formed by lithospheric stretching north of the Tornquist fault system and is related tectonically and in time to the last phase of the Variscan orogeny. The main graben forming period in the Oslo Region began in Late Carboniferous, culminating some 20-30 Ma later with extensive volcanism and rifting, and later with uplift and emplacement of major batholiths. It ended with a final termination of intrusions in the Early Triassic, some 65 Ma after the tectonic and magmatic onset.
We divide the geological development of the rift into six stages. Sediments, even with marine incursions occur exclusively during the forerunner to rifting. The magmatic products in the Oslo Rift vary in composition and are unevenly distributed through the six stages along the length of the structure.     

1999年土耳其Izmit Mw7.6地震的持续成核过程

实验室和理论研究表明,地震之前会出现一个渐进性的滑动不稳定阶段,在此期间,断层缓慢滑动,而后突然加速并最终导致动态破裂.本文中,我们报道了迄今记录最为完整的大地震之一,即1999年土耳其Izmit Mw7.6地震之前出现了持续时间很久的源自震源的地震信号.这种信号包含一连串的地震破裂,破裂随时间和低频地震噪声的增加而加...     

华南板块南缘早中生代的逆冲推覆构造及其相关的动力学背景

作为理解华南构造演化的关键地区,在华南板块南缘的云开地体和越北的Song Chay地体发育了早中生代的向北东逆冲推覆的韧性变形.在云开地体,经历角闪岩相和绿片岩相变质的矿物指示了产状平缓的面理上发育明显的北东-南西向矿物拉伸线理.沿着这些矿物拉伸线理,具有上部指向北东的剪切变形.同位素年代学的定年结果指示了变形事件发生...     

Seismic vulnerability evaluation of axially loaded steel built-up laced members Ⅱ： evaluations

The test results described in Part 1 of this paper （Lee and Bruneau, 2008） on twelve steel built-up laced members （BLMs） subjected to quasi-static loading are analyzed to provide better knowledge on their seismic behavior. Strength capacity of the BLM specimens is correlated with the strength predicted by the AISC LRFD Specifications. Assessments of hysteretic properties such as ductility capacity, energy dissipation capacity, and strength degradation after buckling of the specimen are performed. The compressive strength of BLMs is found to be relatively well predicted by the AISC LRFD Specifications. BLMs with smaller kl/r were ductile but failed to reach the target ductility of 3.0 before starting to fracture, while those with larger kl/r could meet the ductility demand in most cases. The normalized energy dissipation ratio, EC/ET and the normalized compressive strength degradation, Cr″/Cr of BLMs typically decrease as normalized displacements δ/δb,exp increase, and the ratios for specimens with larger kl/r dropped more rapidly than for specimens with smaller kl/r; similar trends were observed for the monolithic braces. The BLMs with a smaller slenderness ratio, kl/r, and width-to-thickness ratio, b/t, experienced a larger number of inelastic cycles than those with larger ratios.     

朱森

朱森,字子元,湖南郴县人。1928年毕业于北京大学理学院地质系,后入中央研究院地质研究所任助理员,后升任研究员。1934年秋得中华文化教育基金会资助,赴美国哥伦比亚大学深造,1936年1月获硕士学位。1936年秋离美赴欧洲,遍历英、比、法、德、瑞士、意、苏联等国,从事地质考察,1937年11月返回故里。回国后历任重庆大学地质系教授、系主任(1938～1941)、中央大学地质系主任(1941～1942)等职。