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991.
在阳泉矿区寿阳区超深水位岩溶区,采用遥感、地震、地下水动态综合监测、抽水试验等综合勘查方法,基本查明了岩溶含水层段的空间分布特征及补径排条件,岩溶地下水的水化学特征及变化规律.在充分利用各种水文地质信息资料的基础上,对超深水位岩溶区进行了地下水资源评价,节约了近30%的钻探工程量,缩短了勘探周期,取得了良好的经济效益和社会效益. 相似文献
992.
我国矿产资源及矿产品供需形势与建议 总被引:1,自引:0,他引:1
为了让国内地质矿产勘查和矿业经济部门及时了解我国矿产资源及矿产品供需形势,介绍了“2006中国矿产资源及矿产品供需形势分析报告会”的内容要点。着重对2006年前三季度我国矿产品供需形势进行了深入分析。根据我国矿产资源的主要特点、矿产品供需形势及存在的问题,提出了若干建议。 相似文献
993.
刘桂芹 《物探化探计算技术》2007,(Z1)
近年来,由于电子技术的快速发展、勘查市场的旺盛需求以及瞬变电磁法(TEM)的自身优点,使得TEM方法从仪器到方法技术均获长足进展。在此,简述了TEM仪器及方法技术的研究现状与进展,总结了TEM的应用领域,分析了TEM方法目前存在的主要问题,探讨了TEM急需解决的问题及发展方向。 相似文献
994.
瞬变电磁法的现状与发展趋势 总被引:1,自引:2,他引:1
吕国印 《物探化探计算技术》2007,(Z1)
瞬变电磁法在矿产资源等勘查领域已广泛应用,成为寻找铜多金属硫化物矿床的重要方法。这里综述了国内外瞬变电磁仪器的性能和主要技术指标,简要分析了部分仪器存在的缺陷,总体上国外TEM仪器的性能优于国内产品。国外解释软件的可视化和集成度相对较高,在实际资料反演和成像的解释方面,国内外基本处于同一水平。近期一维反演和二维电阻率成像仍是TEM资料解释的主要手段,复杂地电条件的三维反演技术在短期内达到实用化较难。 相似文献
995.
We present here a methodology implemented within a geographical information system (GIS) for hazard mapping of small volume
pyroclastic density currents (PDCs). This technique is implemented as a set of macros written in Visual Basic for Applications
(VBA) that run within GIS-software (i.e. ArcGIS). Based on the energy line concept, we calibrated an equation that relates
the volume (V) and the mobility (ΔH/L) of single PDCs using data from Soufrière Hills volcano (Montserrat) and Arenal volcano (Costa Rica). Maximum potential run-outs
can be predicted with an associated uncertainty of about 30%. Also based on the energy line concept and with data from Soufrière
Hills volcano and Mt. St. Helens (USA), we were able to calibrate an equation that predicts the flow velocity as a function
of the vertical distance between the energy line and the ground surface (Δh). Velocities derived in this way have an associated uncertainty of 3 m s−1. We wrote code to implement these equations and allow the automatic mapping of run-out and velocity with the inputs being
(i) the height and location of the vent (ii) the flow volume and (iii) a digital elevation model (DEM) of the volcano. Dynamic
pressure can also be estimated and mapped by incorporating the density of the pyroclastic density current (PDC). This computer
application allows the incorporation of uncertainties in the location of the vent and of statistical uncertainties expressed
by the 95% confidence limits of the regression model. We were able to verify predictions by the proposed methodology with
data from Unzen volcano (Japan) and Mayon volcano (The Philippines). The consistencies observed highlight the applicability
of this approach for hazard mitigation and real-time emergency management. 相似文献
996.
J. A. Akudago K. Kankam-Yeboah L. P. Chegbeleh M. Nishigaki 《Hydrogeology Journal》2007,15(4):789-797
Some of the main problems in well construction are associated with installation of casing, especially in the overburden. A total of 1,485 lined and open wells, drilled in the hard rocks of the Precambrian basement complex and Palaeozoic sedimentary (Voltaian) formations in northern Ghana were studied. Of these, 500 were directly monitored. It was observed that the surfaces within the production zones of open wells had weathered, leading to silting and reductions in depth and yield, posing physical water-quality challenges. Also, the average life span of the open wells is about 15 years. The fully lined wells, on the other hand, perform very well with time, lasting for over 40 years on average, with a more sustainable physical water quality over their life span. The comparative cost of constructing an open well was found to be about 26% less than that of a lined well due to less construction material requirements. Although open wells may be relatively cheaper than lined wells to construct in hard rocks, the life span is shorter and should not be encouraged for groundwater exploitation especially in community or rural water supply schemes. 相似文献
997.
The lowest unit of the Talchir Formation of Talchir Basin, Orissa, was described by pioneer workers as the ‘basal boulder
bed’. In an attempt to explain the co-existence of gravel and clay, materials of contrasting hydraulic properties, a probable
situation resembling the effects of the action of ground-ice enabled boulders to be carried down by sluggish currents resulting
in an intermixture of large boulders and fine mud was conceived. Misinterpretation of this conclusion led to a general tendency
to describe the ‘basal boulder bed’ as ‘glacial tillite’. However, the unit described as ‘basal boulder bed’ is actually represented
by a matrix rich conglomerate with pockets of normally graded silty clay. The present study reveals that the depositional
imprints preserved in this part of the sedimentary succession indicate emplacement of successive debris flows generated through
remobilization of pre-existing unconsolidated sediments. Small pockets of fine-grained turbidites presumably deposited from
the entrained turbidity currents associated with the debris flows suggest the composite character of the debris flow deposit. 相似文献
998.
能源市场的供求关系,关系到经济发展的潜力问题,同时也是制订能源规划的基础。云南省要想在今后几十年内保持高速度的经济增长,必然需要充足的能源供应。根据云南省能源供求的历史和现状;预测2010年能源需求发展趋势;得出经济增长迅速、人均生活水平提高较快、产业结构不合理等是能源供小于求的主要原因;最后提出确立能源建设重点和石油替代路线、转变经济增长方式、大力发展循环经济、提高能源使用效率、合理调整产业结构等解决能源供求矛盾的对策。 相似文献
999.
Trickle Down? Private sector participation and the pro-poor water supply debate in Jakarta, Indonesia 总被引:1,自引:0,他引:1
Karen Bakker 《Geoforum》2007,38(5):855-868
Private sector partnerships (PSPs) have been increasingly advocated as an instrument of ‘pro-poor’ water supply policies. This article examines the performance of the private sector with respect to network connections for poor households in Jakarta, Indonesia, drawing on three sources: data collected through a household survey of poor households in six Jakarta neighbourhoods in 2005; data provided by the two private concessionaires and the Jakarta municipal government; and interviews with water supply managers, government officials, and NGO representatives in 2001 and 2005. The analysis concludes that the Jakarta PSP contract has not been pro-poor: new connections were preferentially targeted at middle and upper-income households over the period 1998-2005, and the numbers of new connections have been lower than the original targets. The paper argues that the failure to connect the poor is not solely attributable to the private operators, and identifies disincentives to provide individual network connections to poor households on the part of the municipality, the private concessionaires and poor households. The paper concludes by questioning the long-term ability of private sector operators to supply water to the poor. 相似文献
1000.