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731.
本文分析了影响永乐油田葡萄花油藏薄差油水层解释精度的因素,提出了永乐油田薄差层流体识别的有效方法,为外围油田新区钻井运行及射孔方案编制提供较为准确的基础数据。 相似文献
732.
YANQin ZHANGJixian 《地球空间信息科学学报》2002,5(2):51-55
This paper gives some guidelines of land use planning firstly.A framework of agriculture land use planning is designed based on land use suitability evaluation using integrated technologies of RS and GIS.Further work expected is also given. 相似文献
733.
CHEN Wei‐Min HUANG Young‐Ching Yoshiyuki IIZUKA LO Ching‐Hua WU Hanquan SONG Shuguang YANG Jingsui XU Zhiqin YANG Houng‐Yi 《《地质学报》英文版》2002,76(1):44-62
After the integration of petrographic study, geothermobarometry and Gibbs method, the synthetic P-T paths for the rocks from different geological profiles in the North Qilian, China, have been derived. The composite P-T paths from different methods indicate that all the high-pressure rocks in the Qilian area recorded P-T paths with clockwise loops starting at the blueschist facies, later reaching peak metamorphism at the blueschist facies, eclogite fades or epidote-amphibolite facies and ending up with the greenschist facies. The incremental Ar-Ar dating shows that the plateau ages for the high-pressure rocks range from 410 to 443 Ma. The plateau ages could be used as a minimum age constraint for the subduction that resulted in the formation of these high-pressure rocks in the Qilian area. It is proposed that the late-stage decompressional and cooling P-T paths with ends at the greenschist facies for these high-pressure rocks probably reflect the uplift process which could occur after shifting the arc-t 相似文献
734.
735.
On steps and methods for the establishment of global boundary stratotype section and point (GSSP) from the viewpoint of integrated stratigraphy 总被引:3,自引:2,他引:3
王训练 《中国科学D辑(英文版)》2002,45(11):1027-1041
The steps and methods for the establishment of the global boundary stratotype section and point (GSSP) are summed up briefly as follows. (i) Select rock sequences of approximately the same age duration in a region, make a thorough study of their properties or attributes in order to establish the high-resolution stratigraphic units reflecting the natural rhythms in Earth's history, and proceed by multidisciplinary comprehensive studies to reveal the relationship, including time-space relation and possible mutual causality, among the various stratigraphic units and the different natural rhythms established. (ii) Seek for the "natural break" that represents the "major natural changes in the historical development of the Earth" in shallow marine facies areas, which is frequently the third-order sequence boundaries. (iii) Trace from shallow marine facies areas toward the continental slope and bathyal areas to seek for a continuous depositional sequence that corresponds in time span to the "natural break" of shallow marine facies areas. (iv) Seek for a horizon within the continuous depositional sequence that approximately coincides with the maximum regressive point in the "natural break". This horizon is commonly within a lowerstand systems tract (LST) or a shelf margin systems tract (SMST) of the relevant third-order sequence. (v) Seek immediately above this horizon of maximum marine regression for an organic radiation or explosion event closely related to the natural boundary, which is generally the first flooding surface (FFS) of the relevant third-order sequence. (vi) Select within the organic event deposits closely related to the FFS the base boundary of a fossil taxon with widest geographical range as the Leading Group biozone for designation of the stratigraphic boundary. (vii) Select from among the sections with continuous depositional sequence formed under similar sedimentary palaeogeographic background (in general continental slope or bathyal environments) the section which possesses the shortest distance between the base boundary of the Leading Group biozone and the immediately underlying FFS of the relevant third-order sequence as the global stratotype section. The first appearance datum (FAD) of the Leading Group biozone species in the section may be regarded as the ideal GSSP. The steps suggested above are a supplement and improvement of the currently used procedures and methods for establishing GSSP. The GSSP established by using the steps and methods suggested here would make the stratigraphic boundaries better reflect the "major natural changes in the historical development of the Earth", more readily distinguishable and easily operable in recognition and correlation, and at the same time also make the designation of boundaries more objective. 相似文献
736.
Aerial photograph interpretation on erosion trends from 1961 to 1998 showed that by 1998, approximately 17 and 50% of agricultural
land in Ndome and Ghazi respectively had been permanently lost due to the combined effect of rill, inter-rill, and gully erosion,
and sand deposition. Although abnormally heavy rains received between 1996–98 caused much of the present land damage, the
severity of the damage was enhanced by inappropriate and persistent human perturbations in the land-system notably through
vegetative degradation and destruction of soil structure through inappropriate tillage practices. With soil organic matter
contents of 1.6 and 1.9%, and clay ratios of 10.1 and 10.6 for Ndome and Ghazi, respectively, the areas inherent erodibility
was considered as high thus pointing to the need for careful use and management of the soil resource. That farmers appreciated
only land quality indicators that were visible to the naked eye and that directly affected their subsistence, revealed a knowledge
gap that saw damages from intrinsic processes like rill and inter-rill erosion proceed unnoticed. This paper argues that the
spread of erosion damage in rural agro-ecosystems is survival-driven. And as a remedy to this problem, there is need for the
diversification of livelihood endeavours to alternative off-farm income sources to reduce pressure on the already fragile
land resource. Further, being the ultimate implementers of conservation technologies and by virtue of the multiplicity and
inter-relation of rural household needs, adoption of an integrated erosion management approach with food security as paramount
presents the most practical entry point for sustainable land management in such rural agro-ecosystems.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
737.
研究在已实现可视通信的ISDN多媒体卡上,通过芯片的功能复用,设计一个驱动程序模型,以实现ISDN多媒体卡的拨号上网功能。简要介绍了ISDN接入因特网的通信协议体系,详细探讨了ISDND信道的呼叫过程,分析了拨号上网原理有如何与Widnows系统的远程访问服务结构相结合。给出了一个基于NDIS标准的ISDN多媒体卡的小端口驱动程序的设计与实现方案。 相似文献
738.
739.
通过对北京西北部周边地质环境现状及成因的分析研究,阐述了开展北京乃至整个华北生态环境调查的深远影响和重要意义,并提出了针对性的建议。 相似文献
740.
基于GIS与工作流技术的图文一体化地籍管理信息系统的设计 总被引:12,自引:0,他引:12
随着信息技术和互联网络的发展,传统的地籍管理信息系统已经不能满足土地管理部门的需要。通过对GIS技术和工作流技术的分析,确定了地籍管理信息系统的结构模型和功能模型。通过GIS与工作流的集成,达到地籍图、文、表信息的统一管理,建成图文一体化的地籍管理信息系统。 相似文献