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791.
李泉  屈卉 《陕西地质》2006,24(2):50-56
本文在分析陈仓区地下水开采现状和水文地质条件的基础上,建立了水文地质概念模型,选用了承压水二维非稳定流数学模型进行描述,采用无越流的无界承压含水层干扰井群法求解该数学模型。  相似文献   
792.
四川丹巴白云母矿山公园矿业遗迹资源特征及评价   总被引:1,自引:0,他引:1  
四川丹巴白云母矿是我国开发最早的白云母矿之一。在悠久的开采历史中遗存下了十分丰富的矿业遗迹,成为该公园建设的基础。这些遗迹典型、稀有,系统完整,科学价值高,组合独特,具有很高的历史文化价值。此外,公园内配套的自然人文景观丰富,旅游区位条件良好,矿业遗迹开发价值巨大。  相似文献   
793.
During hard coal mining operations conducted under conditions of rockburst hazard, one of the most important preventive measures can be the prediction of occurrence time and location of the strong seismic mine tremors of energy E s ⩾ 104 J. This is a very difficult task and the way it is being currently performed appears to be unsatisfactory. Therefore, attempts have been made to use neural networks, specifically trained for this application. The paper presents an approach for determining an influence of the type and shape of the input data on the efficiency of such a prediction. The considerations are based on a selected example of the seismic activity recorded during longwall mining operations conducted in one of the Polish mines.  相似文献   
794.
Impact of karst water on coal mining in North China   总被引:1,自引:0,他引:1  
Coalfields in North China encompass more than ten Provinces. They contain six to seven coal seams in the Permo-Carboniferous strata. The lower three seams account for 37% of the total reserves and are threatened with intrusion of karst water from the underlying Ordovician limestone. Hundreds of water inrush incidences have occurred, in which a large amount of water suddenly flows into tunnels or working faces under high potentiometric pressure. Over 50 mines have been flooded over the last 30 years. Large-scale dewatering or depressurizing of the karst aquifer was considered essential to avoid water inrushes and keep the mines safely operational. This practice, however, has caused sinkholes, dry springs, water supply shortage, and groundwater contamination in the surrounding areas. One alternative water control measure is to make full use of the rock layer between the coal seam and the karst aquifer as a protective barrier to prevent or constrain water flow from the underlying aquifer into the mines. Grouting is effective when the hydrogeological conditions are favorable to this technique. Proper design of the grouting program and experience of the contractor are also important for a successful application.  相似文献   
795.
Computer-based landscape evolution models offer the ability to evaluate landscape stability over the short (annual), medium (decades to hundreds of years) and long-term (thousands of years). Modeling has advantages in that design ideas can be tested, different surface material properties can be evaluated and risk analysis carried out. Landscape evolution models allow landscape surface change through time. These models also offer the advantage that the landscape can be evaluated visually as it develops through time, which is not possible with other types of models. Landscape evolution models can be used for not only soil loss assessment (i.e. tonnes/hectare/year), but also to evaluate the method of soil loss (i.e. rill or interrill erosion). This study examines a range of waste rock dump designs for the Minera Alumbrera Ltd. copper mine, Argentina. An erosion assessment using the SIBERIA erosion model over a 1000-year simulation period demonstrates waste rock dump designs using a conventional stepped design of backsloping benches and caps with angle of repose slopes provide the lowest average erosion rates and depths of incision than do other designs. Caution should be applied in interpreting these results as the SIBERIA erosion model is sensitive to parameter input and in this case was calibrated and run using a generic set of parameters that are not site specific. Nevertheless, the results provide a guide as to the strengths and weaknesses of different rehabilitation designs and demonstrate the insights that modeling studies can provide.  相似文献   
796.
A sediment core from the Liangzhi Lake, Hubei Province in central China, was used to assess metal usage and accumulation in the past 6000+ years in China. The concentrations of trace metals, including Cr, Cu, Pb, Ni and Zn, and major elements, Ca, Fe and Mg, in the ^14C-dated sediment core were analyzed. Historical trends of metal inputs to the Liangzhi Lake from 5000 B.C. to the present were recorded in the sediments, representing over 6000 years of metal mining and utilization history in China. The concentrations of Cu, Ni, Pb and Zn have increased gradually since 3000 B.C., indicating the start of the Bronze Age era in ancient China, until the period 467-76 B.C. During the period of 467-76 B.C., there had been a rapid increase in the concentrations of these metals in the sediments, indicating the enormous inputs of these metals at that time. This era corresponded well with the Warring States Period (475-221 B.C.) and early Hart Dynasty (206 B.C.-220 A.D.) of China, during which copper and lead were extensively used in making bronze articles, such as vessels, tools and weapons. During 1876 A.D. to the early 1900s, there was also a significant increase in the metal concentrations, such as Cu, Ni and Pb, which could probably reflect the impact of metal emissions during the early industrial development and wars in China. The Pb isotopic analysis showed that the surface and subsurface sediments had lower ^206Pb/^207Pb, and ^208Pb/^207Pb ratios than the deeper layers, affected by mining activities both during the Bronze Age era and modem times.  相似文献   
797.
结合具体工程项目,分析了各种因素对大型高耸烟囱的影响,介绍了烟囱允许倾斜值的理论和经验计算方法,为评价和预测烟囱的稳定性提供了理论依据和实用的计算方法。  相似文献   
798.
石伟 《地震工程学报》2006,28(4):377-378
数据仓库是近年来信息领域中迅速兴起的一种技术。本文对此技木和应用进行了讨论,提出了适用于地震信息系统数据仓库的方案设计思想。  相似文献   
799.
地震学在减轻矿山地质灾害中的应用进展   总被引:10,自引:1,他引:10  
综述了煤矿安全对于地球物理应用的需求,以及近年来地震学在煤矿减轻地质灾害的应用进展,特别是微震监测分析在若干典型煤矿应用得到的初步成果。这些成果不但对于煤矿安全具有重要意义,而且对于认识构造地震成因和验证预测方法,也具有中尺度试验意义。  相似文献   
800.
在充分收集蔚县矿区勘探资料、生产矿井资料的基础上,进行了归纳整理与分析研究,总结出矿区奥陶系下统灰岩岩溶发育规律(岩溶发育程度在平面上划分为三个区,垂向上大致可分为三个带)及岩溶水的赋存条件,并提出了受奥陶系下统岩溶水威胁的1、5号煤层的以防为主,带压开采、不直接疏排岩溶水的技术和方法和开采对策。  相似文献   
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