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991.
通过系统分析影响矿产资源勘查风险的基本因素,对前人确定勘查风险系数的方法-费用效益法、概率统计法进行了全面的评述,认为在实际操作上存在较大的困难,计算结果的准确性并不可靠。从统计地球化学理论出发,考查了矿产资源勘查和开发全过程中技术、经济参数对投资效果的影响,推导出矿产勘查投资利润率的计算公式,并将其与安全利率相比较。达到计算矿产资源勘查风险的目的。  相似文献   
992.
管道地质灾害风险分级-以忠县-武汉输气管道为例   总被引:1,自引:0,他引:1  
结合输油气管道的特点,提出了一套管道地质灾害的风险分级方案。所提出的风险分级标准将体现地质灾害易发性作为风险分级的主体,考虑了管道作为核心承灾体的地质灾害危害性,并兼顾考虑周围环境的影响,且立足于野外地质灾害详细调查阶段,具有简便、快速、可操作性强的特点。以忠县—武汉输气管道地质灾害为例,进行了风险分级,并基于风险分级提出了整治规划。  相似文献   
993.
The original methods of seismic risk assessment based on the main factors, defining the high level of seismic risk in Armenia, are used in this paper. Based on the analysis carried out, an assessment is made about the fact, that the capital of Armenia, Yerevan, is the most risk exposed area. A strategy for seismic risk reduction, derived from local peculiarities and the level of seismic risk, is presented. Improving the resisting of existing buildings and constructions to seismic damage, based on the grounds of new technologies elaborated by NSSP RA, is emphasised in this strategy.  相似文献   
994.
针对老挝爬奔金矿的工程地质条件及水文地质条件展开调查,首先根据地质调查与钻探揭露其地层岩性,分析其地层分布、岩土体特性和地质构造,分析了地表水、地下水腐蚀性,认识了爬奔金矿矿区的工程地质特征;其次对矿区潜在地质灾害进行野外调查、分类,对矿区边坡稳定性进行了分析,同时分析了矿区的地质灾害危险性等级,并提出了相对的防治措施。  相似文献   
995.
张斌 《安徽地质》2006,16(1):9-15
自上个世纪90年代以来,我国经济的高速发展引发了石油消费的快速增长,石油对外依存度逐年提高。为确保国家石油安全,中国三大石油公司作为国家“走出去”战略的实践者,大力开拓海外石油市场,取得了初步的成效。本文从中东地区某资源国一个石油风险勘探项目入手,通过分析中国石油公司在该资源国实施石油风险勘探项目过程中遇到的问题和困难,然后以点带面,重点从国家层面上有针对性地提出了解决问题的建议,以推动和保证海外风险勘探事业的持续和良性发展。  相似文献   
996.
王静  吴宇峰  王斌  张磊  王鑫  赵一 《岩矿测试》2015,34(4):464-470
毒性淋溶提取法(TCLP)是美国法定的一种生态环境风险评价方法,通过提取土壤中的重金属有效态判断土壤重金属污染状况和评估污染区域生态风险。本文应用TCLP法提取天津市某工业园区内及周围农田土壤中的有效态Cu、Pb、Zn、Cd,采用电感耦合等离子体质谱法和原子吸收光谱法分别测定重金属全量和有效态,结合单项污染指数和内梅罗综合污染指数评价了重金属生态风险。结果表明:研究区Zn是首要污染物,主要来源于镀锌厂、金属制品厂和电镀厂,其次是Pb和Cu污染,Cd无污染;Pb、Zn可能具有同源性或伴生关系;大部分土壤处于安全水平,重金属污染率不到30%,但农田土壤出现了Zn的轻度污染。重金属全量是影响重金属有效态含量较大的因素,当Zn全量大于环境质量标准限值(300 mg/kg),Pb全量大于80mg/kg时,有效态Zn、Pb与其全量均呈正相关。因此,可以使用TCLP法将土壤重金属全量与有效态进行量化评价重金属生态风险。  相似文献   
997.
山区道路工程建设用地地质灾害危险性评估技术探讨   总被引:1,自引:0,他引:1  
地质灾害对建设项目造成破坏,因此,在项目建设前进行建设用地地质灾害危险性评估就显得特别重要。在评估过程中,只有对灾害体类型、规模、影响范围、稳定性、危险性和危害程度做出准确的评估,评估结论才能成为拟建项目后续工作的科学依据。文章以某山区道路改造项目为例,探讨了山区崩塌危岩、泥石流灾种的地质灾害危险性评估的定性、半定量评价方法,并根据评估结果,提出了相应的治理方案。本文提出的评估方法在类似项目地质灾害危险性评估中具有参考和借鉴价值。  相似文献   
998.
在深圳抽水蓄能电站区域地质构造背景分析的基础上,认为深圳大断裂和横岗-盐田断裂是控制电站场址区域构造稳定性的重要断裂,挽近期以来活动较明显,但全新世或晚更新世以来趋于稳定,对本电站场址构造稳定性没有构成威胁.同时,对地震危险性进行了进一步研究分析,并综合评价了场址区的构造稳定性问题.根据地震危险性分析结果以及未来50年10%概率烈度计算值,本场址基本烈度为Ⅶ度,本工程场地可按Ⅶ度抗震设防.  相似文献   
999.
The universal soil loss equation (USLE) is an erosion model to estimate average soil loss that would generally result from splash, sheet, and rill erosion from agricultural plots. Recently, use of USLE has been extended as a useful tool predicting soil losses and planning control practices by the effective integration of the GIS-based procedures to estimate the factor values on a grid cell basis. This study was performed for five different lands uses of Indağı Mountain Pass, Cankırı to predict the soil erosion risk by the USLE/GIS methodology for planning conservation measures in the site. Of the USLE factors, rainfall-runoff erosivity factor (USLE-R) and topographic factor (USLE-LS) were greatly involved in GIS. These were surfaced by correcting USLE-R site-specifically using DEM and climatic data and by evaluating USLE-LS by the flow accumulation tool using DEM and watershed delineation tool to consider the topographical and hydrological effects on the soil loss. The study assessed the soil erodibility factor (USLE-K) by randomly sampled field properties by geostatistical analysis. Crop management factor for different land-use/land cover type and land use (USLE-C) was assigned to the numerical values from crop and flora type, canopy and density of five different land uses, which are plantation, recreational land, cropland, forest and grassland, by means of reclassifying digital land use map available for the site. Support practice factor (USLE-P) was taken as a unit assuming no erosion control practices. USLE/GIS technology together with the geostatistics combined these major erosion factors to predict average soil loss per unit area per unit time. Resulting soil loss map revealed that spatial average soil loss in terms of the land uses were 1.99, 1.29, 1.21, 1.20, 0.89 t ha−1 year−1 for the cropland, grassland, recreation, plantation and forest, respectively. Since the rate of soil formation was expected to be so slow in Central Anatolia of Turkey and any soil loss of more than 1 ton ha−1 year−1 over 50–100 years was considered as irreversible for this region, soil erosion in the Indağı Mountain Pass, to the great extent, attained the irreversible state, and these findings should be very useful to take mitigation measures in the site.  相似文献   
1000.
We present the methodologies adopted and the outcomes obtained in the analysis of landslide risk in the basin of the Arno River (Central Italy) in the framework of a project sponsored by the Basin Authority of the Arno River, started in the year 2002 and completed at the beginning of 2005. In particular, a complete set of methods and applications for the assessment of landslide susceptibility and risk are described and discussed. A new landslide inventory of the whole area was realized, using conventional (aerial-photo interpretation and field surveys) and non-conventional methods (e.g. remote sensing techniques such as DInSAR and PS-InSAR). The great majority of the mapped mass movements are rotational slides (75%), solifluctions and other shallow slow movements (17%) and flows (5%), while soil slips, and other rapid landslides, seem less frequent everywhere within the basin. The relationships between landslide characteristics and environmental factors have been assessed through statistical analysis. As expected, the results show a strong control of land cover, lithology and morphology on landslide occurrence. The landslide frequency-size distribution shows a typical scaling behaviour already underlined in other landslide inventories worldwide. The assessment of landslide hazard in terms of probability of occurrence in a given time, based for mapped landslides on direct and indirect observations of the state of activity and recurrence time, has been extended to landslide-free areas through the application of statistical methods implemented in an artificial neural network (ANN). Unique conditions units (UCU) were defined by the map overlay of landslide preparatory factors (lithology, land cover, slope gradient, slope curvature and upslope contributing area) and afterwards used to construct a series of model vectors for the training and test of the ANN. Various different ANNs were selected throughout the basin, until each UCU was assigned a degree of membership to a susceptibility and a hazard class. Model validation confirms that prediction results are very good, with an average percentage of correctly recognized mass movements of about 85%. The analysis also revealed the existence of a large number of unmapped mass movements, thus contributing to the completeness of the final inventory. Temporal hazard was estimated via the translation of state of activity in recurrence time and hence probability of occurrence. The following intersection of hazard values with vulnerability and exposure figures, obtained by reclassification of digital vector mapping at 1:10,000 scale, lead to the definition of risk values for each terrain unit for different periods of time into the future. The final results of the research are now undergoing a process of integration and implementation within land planning and risk prevention policies and practices at local and national level.  相似文献   
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