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61.
本文通过对高密度电阻率法勘探中的长测线多排列数据进行连接处理,实现了同一测线采用同一套参数的规范化处理,克服了因不同排列采用不同参数处理而导致假异常和信息丢失等弊端,同时解决了在成像时,因各个电性剖面的色标值不一致,剖面坐标与实际桩号对应不直观,导致对整个区域的电性趋势认识产生误导的问题.从实例处理来看,能为整个勘探区提取更丰富的电性信息,不但突出了整条测线的地下电性趋势,更客观、更全面地把握和认识勘探地区的电性分布规律,而且从宏观上把握了一些比较隐蔽的地质现象. 相似文献
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为准确确定露天煤矿地下水分布与类型,根据不同赋存条件电磁差异,基于磁场强度与电阻率参数进行异常划分与类型判别。以新疆某露天煤矿为例,采用高精度磁法通过磁异常强度确定烧变岩边界,并采用高密度电法和瞬变电磁法通过电阻率圈定低阻异常区,结合异常响应差异分别推断地下水分布范围与赋存类型。地面钻探验证探测成果的准确性。结果表明:露天煤矿烧变岩水与砂岩裂隙水电磁响应差异明显,基于磁场强度与电阻率的双参数综合电磁法能准确圈定其分布范围,并判别其赋存类型。 相似文献
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热开采法、抑制剂刺激法等传统天然气水合物开采方法将破坏水合物地层,不能有效地解决海底地层破坏和开采使用化石燃料燃烧后所存在的碳储存和碳捕捉问题.介绍了低温固体氧化物燃料电池法开采天然气水合物的方法.该方法利用CO2置换天然气水合物地层中的甲烷,运送到低温固体氧化物燃料电池的阳极,在阴极通入空气,发生电化学反应,产生电能,并将产出的CO2通入到天然气水合物地层,置换出甲烷.该方法简单、实用,克服了传统开采方法所存在的问题,发电效率较传统发电方法大幅提高. 相似文献
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Dimitris A. Retalis 《Pure and Applied Geophysics》1991,136(2-3):217-233
In the present study, we examine the daily and annual variation of the air-earth current density in Athens for all weather as well as for fair weather for a 16-year period 1965–1980.The daily variation of the air-earth current density has a definite bimodal form while the annual variation has no definitive form but simply reaches its larger values during the summer months. There has also been a Fourier analysis of the daily variation.Furthermore, and for a 3-year period 1968–70, we present the mean daily and annual variation of the electric field, air-earth current density and total conductivity of the air. Based on these parameters we have estimated the conduction and the convection current and we have correlated them to the total (measured) current. In addition, we have estimated the values of the parameter, in order to test the fulfillment of Ohm's law in atmosphere. 相似文献
65.
Martin Oteng-Ababio Ian Smout Ebenezer Forkuo Amankwaa James Esson 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2017,117(2):142-154
AbstractIn most developing countries, the provision of municipal services and infrastructure invariably fails to match the pace and demands of urbanization. The outcome is often increased informality due to improper planning, official bureaucratic barriers and perhaps insufficient and shrinking public resources, which then makes leveraging private capital for public service provision imperative. Drawing on in-depth qualitative fieldwork in two Ghanaian cities, this paper aims to extend literature on the divergence between service provision and urbanization in developing countries. More specifically, it attempts to qualify recent macro-level data indicating that access to water, sanitation and electricity services in Accra and Sekondi-Takoradi is improving substantively. Contrary to dominant policy narratives circulating in Ghana, we illustrate how the acceptability of key municipal services within urban settings is often inadequate, and how acceptability is tied to spatial and temporal factors. We then identify and examine the reasons underpinning these variations. Through exploring residents’ perceptions of key services, and examining critically the possibility and feasibility of meeting urban service needs through leveraging private resources, this paper contributes to broader academic debates over urban service provision, while also feeding into contemporary policy discussions concerning how to achieve several of the Sustainable Development Goals by 2030. 相似文献
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城市用电量预测是电力及相关经济部门开展电力供需形势分析的重要依据。本文选取2004—2014年西安市用电量月度数据和气象数据,建立用电量预测的计量经济模型,在此基础上建立西安市用电量业务化系统,初步应用于西安市未来用电量预测。结果表明,气温与西安市用电量之间表现为稳健的正U型非线性关系;西安市用电量需求高峰主要在冬季,但由于春节等因素,工业用电量在2月大幅减少,居民用电量却显著增加;模型对全社会用电量拟合准确,对未来用电量预测准确率高,具有开展中长期预测的适用能力;通过建立西安城市用电量气象业务系统,将未来天气预报或气候预测结果带入业务系统中,可滚动预测未来12个月可能耗电量,可为调节电力分配提供科学参考,提升电力供应的调度管理水平。 相似文献
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The discovery of cosmic rays, a milestone in science, was based on the work by scientists in Europe and the New World and took place during a period characterized by nationalism and lack of communication. Many scientists that took part in this research a century ago were intrigued by the penetrating radiation and tried to understand the origin of it. Several important contributions to the discovery of the origin of cosmic rays have been forgotten; historical, political and personal facts might have contributed to their substantial disappearance from the history of science. 相似文献