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51.
中山站-Dome A断面考察是国际横穿南极科学考察计划(ITASE)的核心考察路线之一,具有重要的科学意义,在国内外产生了广泛影响。中国第31次南极科学考察内陆冰盖考察期间,采集了中山站-Dome A断面上约10 km间隔的表层雪样品,通过离子色谱实验分析,得出了断面上含硫化合物(SO_4~(2-)与MSA)的含量。在整个断面上,nssSO_4~(2-)和MSA含量表现出微弱的递减变化趋势,呈现出区域性变化趋势。在内陆高原区域(Dome A区域),nssSO_4~(2-)与MSA存在较好的线性关系([MSA]=0.1158×[nssSO_4~(2-)]–1.1497,r~2=0.75)。MSA/nssSO_4~(2-)比值在断面上的变化范围为0.04—0.47,均值为0.14,比值表现为沿海区域高于内陆区域,与低温条件下MSA/nssSO_4~(2-)比值大相矛盾,原因是由于源区的不同或风场而造成的。通过对断面上含硫化合物的研究,为进一步利用冰芯SO_4~(2-)与MSA记录研究过去气候环境提供了科学依据。 相似文献
52.
AfterthereportofdinosaurfootprintsintheEarlyCreta ceousin 2 0 0 0 (Lietal.,2 0 0 0 ) ,wefollowedtounearth ,investi gateandresearchthefootprintswiththesupportofNationalNat uralScienceFundationandStadholderFundofGansuProvince.Atpresent ,therearetentracksitesabout 2 86fo… 相似文献
53.
对六十年代生产的烟熏记录地震仪进行技术改造:保留烟熏记录,保留65摆(或DD—1摆)以ARA积分放大器代替线性放大器,以线性笔头代替积分记录笔,增配电子报警器及交直流自动切换电源,组成新的地震观测仪器系统。技术改造方案在广东地震台网实施、两年来仪器运行正常、效果很好。 相似文献
54.
Ice core is an important object of the global climate change research, and can extract paleoclimate information by physical and chemical methods. As one of the major physical analysis technology, conductivity measurement technology mainly contains two methods and has been applied to many drilling project. The technology reflects the ice core electrical properties influenced by factors such as temperature, pressure, impurities and changes, and the cause of these changes can be explained from the aspects of macroscopic and microscopic. What obtained from measurement can be used to the research of dating, volcanic events, accumulation rate, biomass burning, ion concentration recovery, which systematically help us to understand the quaternary evolution of Antarctic climate since late pleistocene. This paper summarized in detail the main research achievements on electrical properties and dielectric measurement technology of ice core, and also discussed the prospect of the technology in China deep ice core project further. 相似文献
55.
Understanding the effects of organic acids (OA) on the transformation of Fe and Mn to surface water from the weathering coal gangue is of great benefit to risk assessment and remediation strategies for contaminated water and soil. Based on the investigation on surface water in the central coal districts of the Guizhou Province, 18 water samples were collected for heavy metal analysis. The results indicated that the pH value of surface water is low (3.11–4.92), and Fe concentration (1.31–5.55 mg L?1) and Mn concentration (1.90–5.71 mg L?1) were, on average, 10.86 and 34.33 times the limit of Surface Water Quality Standards, respectively. In order to evaluate the effects of the OA on the dissolution of Fe and Mn from the weathering coal gangue, column elution and batch leaching experiments were conducted. The results show that the low molecular weight of organic acids (LMWOAs, i.e., oxalic, tartaric, malic and citric acids) and fulvic acids significantly accelerated the dissolution of Fe and Mn; in addition, when the concentration of OA reached 25 mmol L?1, the concentrations of Fe, and Mn were 1.14–67.08 and 1.11–2.32 times as high as those in 0.5 mmol L?1 OA, respectively. Furthermore, the migration of Fe and Mn was significantly influenced by the pH and Eh, especially for Fe; the ion Mn was dissolved from the gangue more easily than the ion Fe in the column leaching, which was contrary to the results of batch leaching. 相似文献
56.
原中央地质调查所、中央研究院地质研究所和资源委员会矿产测勘处都曾为中国地质事业的发展作出过重要贡献。但是,在1949年以前总体地质人员少、部门分散。为解决解放初期矿产资源紧缺和地质人员短缺的矛盾,1950年8月经政务院批准成立了中国地质工作计划指导委员会,及其领导下的矿产地质勘探局、中国科学院地质研究所和古生物研究所,开始了地质界一元化的机构改革。1951年5月7日新成立的三个机构开始运行,在运行初期实行地质研究人员的双重身份制度,即在矿产地质勘探局为技正,在研究所为研究员。1952年6月初步确定了各单位内设机构和人员,同时各专业地质队陆续成立,开始了人员的再次分配。1952年8月地质部成立,矿产地质勘探局,逐步转变为地质部的不同部门,地质研究所和古生物研究所全面接受地质部的领导。原中央地质调查所在这次变革中人员被分散到新成立的三个部门和有关单位,原来的内设机构被彻底分解,事实上被撤销。原中央地质调查所在长期实践中形成了以调查为本、调查与研究紧密相结合的研究风格和特色,在解放初期,不论是矿产地质勘探局还是中科院地质研究所和古生物研究所都围绕国家急需的矿产资源开展工作,都谈不上与中央地质调查所的机构传承关系。 相似文献
57.
我国于2012年1月在南极Dome A区域正式开展实施了南极昆仑站深冰芯科学钻探工程,截至2021年,钻孔深度已达803.54 m。该工程是我国第一个深冰芯钻探工程,也是国际上第一个在Dome A地区开展的深冰芯钻探项目。本文介绍了昆仑站深冰芯科学钻探工程实施的整体情况,对过去近10年的钻探活动以及取得的成果和经验进行了总结,以期为后续的深冰芯钻探工作提供理论和经验指导。 相似文献
58.
In this study, Qilian Mountain active source airgun signals recorded at 79 stations were obtained after stacking waveforms from July 2015 to December 2016. Based on analysis of the amplitude variation characteristics of the airgun signals, the following conclusions were drawn:along the NW-SE fault distribution direction of the Qilian Mountain area, the decrease in amplitude of airgun signals was relatively slow in relation to the epicentral distance, while the decrease in amplitude in the direction perpendicular to the fault was relatively fast. This difference may be related to the energy loss of seismic waves reflecting and scattering by the regional faults mainly distributed along the NW-SE direction, which are caused by tectonic compression of the Qinghai-Tibet and Alxa blocks. 相似文献
59.
There is growing concern over the effects of climate change on glacier melt and hydrology. In this article, we used two natural small-scale basins, Tuotuo River and Buqu River in the source region of the Yangtze River, China, to show the impacts of glacier melt on stream flow. Changes in the extent of glaciers and ice volume in 1970, 1992 and 2009 are evaluated using remote sensing images. Changes to the glacier surface area over the same time interval are estimated through the delineation of glacier outlines and positions using Landsat TM/ETM+ imagery. By 2009, the glacier surface area had decreased by 20.83% and 34.81% of the 1970 values in Tuotuo River and Baqu River basins respectively. The total meltwater supply in each basin is estimated to be 2.56×10^9 m^3/yr and 1.24×10^9 m^3/yr respectively. Mass balance calculations show that glaciers in the study area suffered a constant mass loss of snow and ice, accumulatively approximately -24 m over the past 40 years. The annual and summer stream flow tended to increase in Tuotuo River basin from 1970 to 2009 while a negative trend of change was shown in Buqu River basin during 1970-1986. Glaciers became shorter, narrower and thinner under the effect of atmospheric warming. Streamflow increase has been recorded at Tuotuo River station in response to increased glacier and permafrost melt. However, streamflow decrease has been recorded at Yanshiping station on Buqu River, where glacier melt has lagged behind atmospheric warming. These results show a close but variable linkage among climate change, glacier melting and water resources in the source region of the Yangtze River. 相似文献
60.
目前,位于东南极冰盖分冰岭中心的冰穹-Dome A已成为深入理解南极冰盖演化、稳定性和找寻地球气候久远记录的研究热点。通过整理总结在Dome A获得的冰川学研究进展,结合国际冰芯科学研究计划(International Partnerships in Ice Core Sciences,简称IPICS)有关寻找最古老冰芯的相关资料,对Dome A的气象要素、地貌、冰厚、冰下地形、冰体流速、冰盖内部结构等环境特征进行归纳分析,讨论Dome A冰川学的最新发展及其对深冰芯钻探计划的影响,并分析概述Dome A深冰芯钻探需考虑的问题和未来发展动向。 相似文献