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351.
陶澍 王学军 胡建英 TAO Shu WANG Xuejun HU Jianying XU Fuliu Liu Wenxin LI Bengang CAO Jun 《地理学报(英文版)》2004,14(Z1)
Over the past several decades,no less remarkable than the fast economic advance has been the pollution of water,air and soil all over China.The degradation of environment provides challenge as well as opportunity to the native scientists.Benefited from their regional-scaled views and unique tools of study,Chinese environmental geographers distinguish themselves from other environment-related scientists by combining geographical methodology with means of chemistry and biology and by emphasizing region-based processes of pollutants and scaling issues.Additionally,they are benefited from the basic trainings in the branches of physical geography,such as soil geography,hydrology and climatology for a better understanding in behavior of pollutants in nature. 相似文献
352.
LU Long WANG Rucheng XUE Jiyue CHEN Fanrong & CHEN Jun . Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China . Department of Earth Sciences Nanjing University Nanjing China 《中国科学D辑(英文版)》2005,48(10)
Pyrite is a common sulfide mineral, particularly abundant in mining waste. It is a focus of mine envi-ronmental concern because the oxidation of exposed pyrite may lead to acid drainage and poisonous mate-rials (like As and heavy metals) release. In the United States, approximately $1000000 per day is spent in alleviating acid mine drainage[1], while the Canadian mining community has environmental liabilities that exceed $2 billion for disposal, management, and rec-lamation of mine waste[2]. … 相似文献
353.
TIAN Jun WANG Pinxian CHENG Xinrong WANG Rujian & SUN Xiangjun . State Key Laboratory of Marine Geology Tongji University Shanghai China . Institute of Geology Geophysics Chinese Academy of Sciences Beijing China . Institute of Botany Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2005,48(10)
The variations of the Earth’s geometry (ETP) pre-dominate climate changes such as monsoon on the Earth[1], serving as its external forcing. The loess/ paleosol sequence in Central China provides a good record of terrestrial deposition to study the evolution of the east Asian monsoon[2―4]. However, the deep sea deposition, due to its high resolution dating and abun-dant climate proxies, should be able to provide more climatic information in the geological time, such as the forcing mechanis… 相似文献
354.
NonlinearRetrievalofAtmosphericOzoneProfilefromSolarBackscaterUltravioletMeasurements:TheoryandSimulation①LiJun(李俊)andLuDaren... 相似文献
355.
Shen Guanglong Wu Xiuyuan Wang Jun Liu Huaqin Department of Geology Northwest U niversity Xi''an Shaanxi Nanjing Institute of Geology Palaeontology Chinese Academy of Sciences Nanjing Jiangsu 《《地质学报》英文版》1995,69(3):329-339
From a fresh field investigation, it has been ascertained that the Late Palaeozoic Yu'erhong (Yuernhung) flora from Yu'erhong, Yumen, Gansu, northwestern China, studied by Bohlin in 1971 includes plants from the Westphalian Yangfukou Formation and the Stephanian to Sakmarian Taiyuan Formation. The Yu'erhong flora from the Yanghukou Formation is dominated by Euramerican elements with a few elements of the Cathaysian flora. No Angarian elements have be found in this section for lack of Late Permian strata. The specimens studied by Bohlin might possibly come from the upper part of the Upper Permian at tne southeastern corner . of the Yu'erhong basin. Those fossils from different horizons and localities might be mixed with each other during collection ;so they fail to reflect the exact horizon of certain plant fossils. 相似文献
356.
Jin Xueshen Jin Yanping Zhao Jun and Dai YinghuaSeismological Bureau of Hebei Province Shijiazhuang China 《中国地震研究》1995,(3)
Based on the site historical earthquake data,a method of seismic risk analysis is presented.Once the frequency of earthquake response intensity and the relative value showed a logarithmic linear,the maximum similarity method would be used to obtain β,λ,and Imax,and also achieve the results of risk analysis on each site.At the same time,the "logic tree" method can be used to calibrate the uncertainty of the risk on each site.Then the final results of risk analysis indicate that this method is feasible,particularly for the sites showing intensity anomaly. 相似文献
357.
The stability question of large-scale horizontal motion in the atmosphere under the effect of Rossby parameter is discussed in this paper by using the qualitative analysis theory of ordinary differential equations. The following as-pects are reviewed: The stability of large-scale horizontal motion in the atmosphere accords with the common inertial stability criterion when the effect of Rossby parameter is not considered (Yang, 1983), and that, on the other hand, the motion will bifurcate two times with the variation of absolute vorticity of basic Zephyr flow at the initial position under the effect of Rossby parameter. Furthermore, in the inertial stable region, if the effect of geostrophic deviation at the initial position is considered, the motion will not only bifurcate but also generate a catastrophe. 相似文献
358.
NUMERICAL EXPERIMENT WITH PROCESSES FOR EFFECT OF AUSTRALIAN COLD AIR ACTIVITY ON EAST-ASIAN SUMMER MONSOON*
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Based on diagnostic results,a numerical study is made of the processes of Australian cold air activity affecting East Asian summer monsoon by using Kuo-Qian P-σ incorporated coordinate five-layer primitive equation spherical band model.Analysis is done of the response to the Southern Hemisphere circulation with and without cold air activity in Australia of the flow,rainfall and diabatic heating fields in the monsoon area of Asia,especially,East Asia,with special attention to the intensification and northward march of the monsoon due to the activity.It is found that the processes for the effect transmission are very analogous to the meridional propagation of quasi-40-day oscillation,together with the meridional wind disturbance showingsouth-north travel and the flow/rainfall fields exhibitirg corresponding movement in this direction,only with a 12-day lag. 相似文献
359.
OptimalUseofHighResolutionInfraredSounderChannelsinAtmosphericProfileRetrieval¥LiJun(李俊)andHuangHung-Lung(黄鸿荣)(Permanentaffil... 相似文献
360.
TheCapabilityofAtmosphericProfileRetrievalfromSatelliteHighResolutionInfraredSounderRadiancesLiJun(李俊)(Cooperativeinstitutefo... 相似文献