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排序方式: 共有4313条查询结果,搜索用时 31 毫秒
911.
网格剖分积分法计算富钴结壳资源量   总被引:1,自引:1,他引:0  
在矿区地质模型建立及边界条件限定的基础上,提出了基于网格剖分积分计算富钴结壳资源量的评估计算方法,推导了相应的计算公式,设计了相应的模块界面,并在"海底地形地貌自动成图系统"中实现了这种计算方法.这种资源量计算方法可应用于富钴结壳资源研究和评价计算.  相似文献   
912.
中国云南玉溪和美国内华达均已发现大量黏土型锂资源,目前关于两地区样品矿物学特征的研究相对不足,而对黏土型锂资源进行充分的矿物学特征研究是锂提取工作开展的重要前提.本文采用X射线荧光光谱、电感耦合等离子体质谱、X射线粉晶衍射、扫描电镜等分析技术,从化学组成、矿物组成、微观形貌等角度对云南玉溪的两个黏土型锂资源样品(YM-...  相似文献   
913.
油气储层流动单元在高、中、低渗储层表征中已经得到普遍应用,但在特低渗储层研究中仍然很少涉及.以松辽盆地北部三肇凹陷升554断块下白垩统泉头组四段扶余油层特低渗储层为例,划分出E、G、P三种流动单元类型,从E类至P类流动单元,渗流能力逐渐减小.流动单元物性特征、空间分布特征均表明流动单元储层非均质性较强.分析了沉积相及开...  相似文献   
914.
张明  杨效  邹丽  唐艳娟  张燕 《气象科技》2021,49(1):63-68
西北区域气象中心高性能计算集群使用LoadLeveler调度管理作业,为实现资源利用率和吞吐量的最大化,本文探讨了作业调度管理的作用和方法.通过配置文件关键字定义队列、设置调度算法和调度器调节参数,将作业的处理需求与可用资源进行匹配,依据实际需求定义集群和各种资源的可用性规则,防止作业之间的相互干扰.结合LoadLev...  相似文献   
915.
肥城矿区地下水资源分析研究   总被引:1,自引:0,他引:1  
为正确认识和解决地下水资源开发利用中存在的问题,通过检测地下水水动力条件和水化学条件的变化,对肥城矿区地下水资源现状进行了科学分析。研究认为:肥城盆地大气降水量的大小将直接影响来年地下水位的高低;四灰和五灰岩溶水中的氟离子含量普遍较高;第四系孔隙水普遍遭受了氮污染,其硝酸盐含量较高,从而使奥陶系含水层中也含有较高的硝酸盐组分;地表水及矿坑水硬度、矿化度都超标,同时存在大量硫酸根;矿井水经沉淀去除悬浮物后,可以达到污水综合排放、景观用水及煤矿井下防尘用水标准。另外,聚类分析和因子分析表明,五灰水与奥灰水普遍存在密切的水力联系。   相似文献   
916.
BOOK REVIEWS     
Book Reviewed in this article: Introduction to Climatology for the Tropics . J. O. Ayoade. Conservation and Management of Natural Resources in the United States . Charles F. Bennett. The Keeping of Animals: Adaptation and Social Relations in Livestock Producing Communities . Riva Berleant-Schiller and Eugenia Shanklin, ed. The Evolution of Geographic Thought in America: A Kentucky Root Wilford A. Bladen and Pradyumna P. Karan, eds. Latin America: Geographical Perspectives , 2nd ed. Harold Blakemore and Clifford T. Smith, ed. The Rural Real Estate Market. Department of Geography Publication Series, No. 18 . Chris Bryant. Urban Geomorphology in Drylands . R. U. Cooke, D. Brunsden, J. C. Doornkamp, and D. K. C. Jones with contributions by J. Griffiths, P. Knott, R. Potter, and R. Russell. Italian Geography, 1960–1980. Meeting of the Status of the Geographic Research in Italy, 1960–1980. Treated under the auspices of Consiglio Nazionale delle Ricerche and organized by Istituto di Geografia Umana della Facoltà di Lettere e Filosofia dell'Università degli Studi di Milano , Giacomo Corna Pellecrini and Carlo Brusa, eds. The Changing Fenland . H. C. Darby. The Future for the City Centre . R. L. Davies and A. G. Champion, eds. Saudi Arabia, Energy, Developmental Planning, and Industrialization . Ragaei El Mallakh, Dorothea H. El Mallakh, eds. For We Are Sold, I and My People: Women and Industry in Mexico's Frontier . Maria Patricia Fernández-Kelly. The Great Lakes Forest: An Environmental and Social History . Susan L. Flader, ed. Regional Transformation and Industrial Revolution: A Geography of the Yorkshire Woolen Industry . Derek Gregory Crime in City Politics . Anne Heinz, Herbert Jacob and Robert L. Lineberry, eds. Revitalizing Cities . H. Briavel Holcomb and Robert A. Beauregard. Cartographic Relief Presentation . Eduard Imhof. H. J. Steward, Trans. Soviet Union: A Geographical Survey . S. V. Kalesnik and V. F. Pavlenko, ed. Cognition and Environment . Stephen Kaplan and Rachel Kaplan. Environmental Protection: The International Dimension . David A. Kay and Harold K. Jacobsen, eds. Mathematical Programming Methods for Geographers and Planners , James Killen. Gentrification Amid Urban Decline: Strategies for America's Older Cities . Michael H. Lang. The North Atlantic Sulphur System . Risto Laulajainen. The Jerusalem Cathedra: Studies in the History, Archaeology, Geography and Ethnography of the Land of Israel, Vol. 2 . Lee I. Levine ed. Jerusalem and Detroit: Recreation Planning and Management . Stanely R. Lieber and Daniel R. Fesenmaier, eds. Heartland and Hinterland: A Geography of Canada . L. D. McCann, ed. Scarborough Where We Live: The Residential Districts of Minneapolis and St. Paul . Judith A. Martin and David A. Lanegran. California: The Geography of Diversity . Crane S. Miller and Richard S. Hyslop. Palo Alto The Dilemma of Amazonian Development . Emilio F. Moran, ed. Boulder Nuclear Waste: Socioeconomic Dimensions of Long-Term Storage . Steve H. Murdock, F. Larry Leistritz, and Rita R. Hamm, eds. Boulder Communism and the Politics of Inequalities . Daniel N. Nelson, ed. The Los Angeles Metropolis . Howard J. Nelson. Dubuque An Historical Geography of Urban System Development: Tidewater Virginia in the 18th Century . James O'Mara. Procedures and Standards for a Multipurpose Cadastre . East Asia: Geographical and Historical Approaches to Foreign Area Studies . Clifton W. Pannell, ed. Dubuque Mackinder: Geography as an Aid to Statecraft . W. H. Parker. Beyond the Urban Fringe: Land Use Issues of Nonmetropolitan America . Rutherford H. Platt and George Macinko, eds. Recreation Geography of the USSR . V. S. Preobrazhensky and V. M. Krivosheyev, eds. Missouri: A Geography . Milton D. Rafferty The Invisible Farmers: Women in Agricultural Production . Carolyn E. Sachs. Cayman Islands Seashore Vegetation: A Study in Comparative Biogeography . Jonathan D. Sauer. Hillslope Materials and Processes . Michael J. Selby. Housing in Britain: The Post-War Experience . John R. Short The Study of Population: Elements, Patterns and Processes . George A. Schnell and Mark Stephen Monmonier. Columbus The Soviet Union: A Systematic Geography . Leslie Symons, ed. The Ottoman Slave Trade and Its Suppression . Ehud R. Toledano. The Impact of Recession on Industry, Employment and the Regions, 1976–1981 . Alan R. Townsend. Landslides and Their Control , 2nd ed. Quido Záruba and Vojtech Mencl. Translated from the Czech by H. Zárubová and V. Mencl.  相似文献   
917.
The Dempster-Shafer theory has been successfully applied to mineral resource potential mapping in G1S environmental. In this applied form, basic probability assignment and combined basic probability assignment are applied to measuring map pattern and map pattern combination, respectively; and the environment composed of the only two singleton sets (deposit set and non-deposit set), is used for expressing the entire map area. For a subarea in which the certain map pattern combination exists, the combined basic probability assignment corresponding to the map pattern combination existing in this subarea, expresses the belief of inferring the subarea belonging to the deposit set from the evidence that the corresponding map pattern combination existing in the subarea. Thus, it may be served as a statistical index measuring the relative mineral resource potentials of the subarea. And it may be determined like 1) dividing the map area into a series of small equal-sized grid cells and then select the training sample set composed of the well-known grid cells or the entire grid cells; 2) estimating the basic probability assignments corresponding to each map pattern from the training sample set; 3) determining the map pattern combination existing in each cell, and then appling the Dempster's Rule of Combination to integrating the all basic probability assignments corresponding to the map patterns existing in the cell into the combined basic probability assignment. Mineral resource potential mapping with the Dempster-Shafer theory is demonstrated on a case study to select mineral resource targets. The experimental results manifest that the model can be compared with the weights of evidence model in the effectiveness of mineral resource target selection.  相似文献   
918.
Occurrence of mineral resources is directly or indirectly controlled by major tectonic processes. Additionally, similar mineral deposit types tend to be concentrated within geologically and tectonically similar areas. As a result, information on the production history of minerals in a well-explored and developed tectonic region—such as within the United States—can be used to estimate resources of geologically similar, underdeveloped tectonic areas elsewhere. For such application, two regions should be compared for geologic similarity using all available geologic information. Estimates of resources based on geologic analogy can be useful in large-scale mineral exploration programs where relatively little geologic information is available, such as in many developing countries. In this study, seven major tectonic regions within the United States are evaluated in terms of estimated mineral value as measured by historical mineral production and economic reserves. The seven regions assessed are: (1) Cordilleran Mountain Belt, (2) Colorado Plateau, (3) Central Stable Region, (4) Canadian Shield, (5) Ozark-Ouachtia Province, (6) Gulf and Atlantic Coastal Plain, and (7) Appalachian Mountain Belt. Regions are ranked in terms of estimated value of (1) 33 major mineral commodities, (2) nonfuel minerals, (3) hydrocarbons, and (4) individual mineral commodities. In terms of total value of historical mineral production and estimated economic reserve amounts of 33 major mineral commodities, the Gulf and Atlantic Coastal Plain is most valuable, with an estimated value of 1980 US$1,970,000/km2. Information on historical mineral production of U.S. tectonic regions may be useful in estimating resources in tectonically similar, underdeveloped regions elsewhere.  相似文献   
919.
If observed oil and gas field size distributions are obtained by random samplings, the fitted distributions should approximate that of the parent population of oil and gas fields. However, empirical evidence strongly suggests that larger fields tend to be discovered earlier in the discovery process than they would be by random sampling. Economic factors also can limit the number of small fields that are developed and reported. This paper examines observed size distributions in state and federal waters of offshore Texas. Results of the analysis demonstrate how the shape of the observable size distributions change with significant hydrocarbon price changes. Comparison of state and federal observed size distributions in the offshore area shows how production cost differences also affect the shape of the observed size distribution. Methods for modifying the discovery rate estimation procedures when economic factors significantly affect the discovery sequence are presented. A primary conclusion of the analysis is that, because hydrocarbon price changes can significantly affect the observed discovery size distribution, one should not be confident about inferring the form and specific parameters of the parent field size distribution from the observed distributions.This paper was presented at Emerging Concepts, MGUS-87 Conference, Redwood City, California, 13–15 April 1987.  相似文献   
920.
This study of the petroleum hydrocarbons in coastal seawater, using dichloromethane extraction withO-terphenyl and n-C_(20) as internal standards, and gas chromatography with silica-capillary-column showedthat the recovery of petroleum hydrocarbons reaches 87.8% and that the lowest detection limit is 0.96μg.This method is reproducible, highly accurate, and applicable for determining the petroleum hydrocarbonsin coastal seawater.  相似文献   
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