中国科学院地理研究工作方向和任务的初步设想(在1965年中国科学院地理工作会议上的报告)   总被引：2，自引：1，他引：1  

竺可桢 《地理研究》1984,3(1):1-7

竺可桢同志1965年在中国科学院地理工作会议上所作的报告,全面分析了我国地理工作的现状和任务,阐明了分工和实现这些任务的措施。竺可桢同志的报告虽然已经过去了近二十年,但现在看起来,仍然有很大的指导意义,本刊特予以刊登,供大家学习参考。虽然报告中有些提法是针对当时情况的,地理研究机构和名称也有调整和变动,但为了保持这个历史性文件的完整,本刊未加更动。  相似文献   

    

Lu Keli  Zhu Yongchun 《大气科学进展》1994,11(4):427-435

The wave rays and their seasonal variation of stationary and low-frequency Rossby waves are studied by using the Runge—Kutta scheme. The results show that for stationary waves the rays can reach lower latitudes in winter, and are limited in higher latitudes in summer. The main differences between the stationary and low-frequency wave rays are that low—frequency waves can propagate across the equator and the easterlies will not be an obstacle on their propagation. It explained to some extent the interaction of disturbances between the Northern and Southern Hemispheres. The lower wave frequencies and the stronger easterly flow are, the more difficult low—frequency waves will be to propagate across the equator. The waves with 20-day period are easier to propagate across the equator than that with 50—day period. The winter is the most favorable season for low—frequency waves to propagate into another hemisphere.  相似文献   

On the formation of void in the Universe     

Shi-Chang Zhu  Guo-Xuan Song 《Astrophysics and Space Science》1983,95(1):197-204

This paper deals with the void with a volume of ～10⁶ Mpc in the Universe. By using spherically-symmetric Einstein field equations the dynamics of void is studied. It seems to be possible that the void will decay in the radiation-dominated era so that the void will amplify and form in the matter-dominated era only.  相似文献   

Toxic effects of Zn2+, Cu2+, Cd2+ and NH3 on Chinese prawn     

Zang Weiling  Xu Xuancheng  Dai Xilin  Zhu Zhengguo  Xu Guirong  Xu Renguo 《中国海洋湖沼学报》1993,11(3):254-259

This study deals with the toxic effects of Zn²⁺, Cu²⁺, Cd²⁺ and NH₃ on Chinese prawn (Penaeus orientalis). The median lethal concentrations of the toxic matters on Chinese prawn were determined. Cd²⁺>Cu²⁺>Zn²⁺>NH₃-Nm is the toxic order of these chemicals to Chinese prawn. The toxic order of concentrated Zn²⁺ and Cd²⁺ in tissues and organs of Chinese prawn is in the order. gill>shell+appendage>viscera>muscle.  相似文献   

依巴谷参考架惯性特征     

朱紫 《天文学进展》2001,19(2):302-306

通过分析和比较依巴谷自行系统与FK2．0自行系统之间的关系，研究了依巴谷系统的惯性问题，指出该系统可能然存在较大的非惯性剩余旋转。  相似文献   

巴颜喀拉山地区第四纪冰期初步探讨     

朱建立 《青海国土经略》1992,(2)

依据地貌、孢粉、岩性沉积特征,划分巴颜喀拉山地区第四纪冰期。并与珠穆朗玛峰、唐古拉山、昆仑山地区进行对比。确定巴颜喀拉山地区第四纪以来有:哈拉滩冰期;巴颜喀拉山冰期;洛曲冰期;汪藏因姆措冰期;折尕考钦新冰期。  相似文献   

1988年1月云南威信墨黑山地灾害     

吴其伟  李德基  朱平一  冯水志 《山地学报》1988,(3)

这次山地灾害由岩崩、滑坡和泥石流三类灾害组成。在我国西南,隆冬少雨季节出现这类山地灾害是罕见的。这次山地灾害正是发生于1988年1月,具有一定的特殊性。究其原因是,当地某些较为特殊的自然条件和采煤不当,促使山体岩崩崩积物逐年加载,进而引起滑坡、泥石流的发生。灾害造成的直接经济损失合人民币58.6万元。对此种山地灾害宜采取以避害为主的防治措施。  相似文献   

Jordan日照记录阈值分析     

Li Jiarui Qian Daojun Zhu Huaming 《成都信息工程学院学报》1989,(1)

本文是通过10个月的日射、日照资料对比观测、统计的乔唐、康氏和光电式日照计记录阈值的平均值和标准偏差,分析了乔唐日照计进光孔径、涂药方式对感光迹线的影响,测定了感光药的吸收光谱,并根据日出日没时直接日射辐照度的平均变化率,估算了由阈值的不确定度引起的日照时数的误差,从而为我国几十年的乔唐日照资料的评价提供依据。  相似文献   

The distribution and natural degradation of cyanide in goldmine tailings and polluted soil in arid and semiarid areas   总被引：2，自引：0，他引：2  

Li Shehong  Zheng Baoshan  Zhu Jianming  Yu xiaoying 《Environmental Geology》2005,47(8):1150-1154

Farmlands and rivers have been seriously polluted by cyanide from a goldmine tailings dam that collapsed in early spring of 1995 in Yining County, Xinjiang Autonomous Region of China. The cyanide distribution in the polluted farmland and the abandoned tailings dam was studied, three and 4 years after the accident occurred. The results indicated that natural degradation of cyanide in soils is slower than in natural water bodies. The cyanide transport in the soil section is similar to freely soluble salts. In arid and semiarid areas, cyanide can be highly enriched in the salt crust in which the concentration is even higher than the fresh tailings debris though cyanide has decomposed for 4 years. In the polluted farmland, the sticky layer in the soil section can highly adsorb and enrich cyanide so it can partly prevent cyanide transfer to groundwater. According to the characteristics of cyanide natural degradation in soil, the measures for prevention and cure of soil polluted by goldmine tailing dam collapse have been discussed.  相似文献   

S-wave velocity and Poisson''''s ratio structure of crust in Yunnan and its implication   总被引：13，自引：2，他引：11  

HU Jiafu  SU Youjin  ZHU Xiongguan & CHEN Yun Geophysical Department of Yunnan University  Kunming  China  Seismological Bureau of Yunnan Province  Kunming  China  Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing  China 《中国科学D辑(英文版)》2005,48(2):210-218

Receiver function of body wave under the 23 stations in Yunnan was extracted from 3-component broadband digital recording of teleseismic event. Thus, the S-wave velocity structure and distribution characteristics of Poisson's ratio in crust of Yunnan are obtained by inversion. The results show that the crustal thickness is gradually thinned from north to south. The crustal thickness in Zhongdian of northwest reaches as many as 62.0 km and the one in Jinghong of further south end is only 30.2 km. What should be especially noted is that there exists a Moho upheaval running in NS in the Chuxiong region and a Moho concave is generally parallel to it in Dongchuan. In addition, there exists an obvious transversal inhomogeneity for the S-wave velocity structure in upper mantle and crust in the Yunnan region. The low velocity layer exists not only in 10.0-15.0 km in upper crust in some regions, but also in 30.0-40.0 km in lower crust. Generally, the Poisson's ratio is on the high side, however it has a better co  相似文献