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41.
Jeffrey J. Cook 《社会与自然资源》2014,27(12):1257-1270
The preproposal stage of the rulemaking process is notoriously understudied, but enormously important in determining regulatory outputs. Recently, Rinfret (2011c) analyzed the U.S. Fish and Wildlife Service (USFWS) rulemaking process and developed a frame analysis model to interpret stakeholder influence during the preproposal stage. Rinfret argues that stakeholders use three frames to influence agency rulemaking, including an expertise, a fiscal feasibility, and an information frame. This article tests this model to determine whether it is applicable to other federal agencies such as the National Park Service (NPS). Through an analysis of stakeholder framing within the 2012 NPS Yellowstone Winter Use Rule, this research confirms that Rinfret's model is indeed applicable to the NPS process. Therefore, this research suggests that this theoretical model examining stakeholder influence is applicable to other public land agencies, and arguably can be applied across the bureaucracy. 相似文献
42.
We suggest a new method for estimating the fractal dimension of the spatial distribution of galaxies: the method of selected cylinders. We show the capabilities of this method by constructing a two-point conditional column density for galaxies with known redshifts from the LEDA database. The fractal dimension of a sample of LEDA and EDR SDSS galaxies has been estimated to be 2.1±0.1 for cylinder lengths of 200 Mpc. A major advantage of the suggested method is that it allows scales comparable to the catalog depth to be analyzed for galaxy surveys in the form of conical sectors and small fields in the sky. 相似文献
43.
Lin Zhu Ren-Xu Chen Yong-Fei Zheng Jing Wang Bing Gong 《Geostandards and Geoanalytical Research》2023,47(1):105-124
An accurate determination of water content in garnet is critical to quantify the transport of water to the deep mantle by the subducted oceanic crust beyond the breakdown of hydrous phases. Fourier transform infrared spectroscopy (FTIR) is the most widely used approach to determine the species and contents of water in garnet. Accurate quantification of OH in garnet requires independent calibration using an external method, as OH absorbance is mineral and composition specific. To obtain the infrared absorption coefficients of structural hydroxyl in garnet, a combined study of spectrometric analyses by FTIR and a method combining a thermal conversion elemental analyser with isotope ratio mass spectrometry (TC/EA-MS) was carried out for fourteen gem-quality natural garnet crystals with variable compositions. The obtained molar absorption coefficients were 9322 ± 338 and 240 ± 26 l mol−1 cm−2 for grossular- and spessartine-rich garnet and pyrope-almandine garnet, respectively. These results are within the range of previous studies. A new molar absorption coefficient of 689 ± 177 l mol−1 cm−2 was obtained for pyrope-spessartine garnet. The large variation in the absorption coefficient indicates it is controlled by both garnet composition and OH-absorption bands. The obtained absorption coefficients are only appropriate for certain types of eclogitic garnet, and more studies should be carried out on eclogitic garnets. 相似文献
44.
45.
V. N. Snytnikov V. A. Vshivkov E. A. Kuksheva E. V. Neupokoev S. A. Nikitin A. V. Snytnikov 《Astronomy Letters》2004,30(2):124-137
We developed a three-dimensional numerical model to investigate nonstationary processes in gravitating N-body systems with gas. We used efficient algorithms for solving the Vlasov and Poisson equations that included the evolutionary processes under consideration, which ensures rapid convergence at high accuracy. We give examples of the numerical solution of the problem on the growth of physical instability in the model of a flat rotating disk with a gaseous component and its three-dimensional dynamics under various initial conditions including a nonzero velocity dispersion along the rotation axis. 相似文献
46.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(5):279-289
In September 2010, a Nature Index giving information on status and trends in biodiversity in nine larger ecosystems in Norway was presented. In the article, the authors ask how Norwegian youth politicians framed, i.e. articulated, the topic of biodiversity after being introduced to this new information. To answer this question, focus group interviews were conducted with leading youth politicians in the six largest political parties in Norway. A first finding was that knowledge of and interest in biodiversity at the outset was relatively low. In general, the interviews were structured along three dimensions. First, there was a general discussion about nature and biodiversity. Second, biodiversity was discussed in a political context in terms of state versus market, and local versus national and international politics. Finally, the role of science was discussed. In general terms, the study found that biodiversity as an issue is only to a limited extent able to influence established political opinions (no resonance), but is itself adapted to fit established ideologies (master frames). 相似文献
47.
Identification of the anomaly component using BEMD combined with PCA from element concentrations in the Tengchong tin belt,SW China 总被引:1,自引:0,他引:1
Concentration of elements or element groups in a geological body is the result of multiple stages of rockforming and ore-forming geological processes.An ore-forming element group can be identified by PCA(principal component analysis)and be separated into two components using BEMD(bi-dimensional empirical mode decomposition):(1)a high background component which represents the ore-forming background developed in rocks through various geological processes favorable for mineralization(i.e.magmatism,sedimentation and/or metamorphism);(2)the anomaly component which reflects the oreforming anomaly that is overprinted on the high background component developed during mineralization.Anomaly components are used to identify ore-finding targets more effectively than ore-forming element groups.Three steps of data analytical procedures are described in this paper; firstly,the application of PCA to establish the ore-forming element group;secondly,using BEMD on the o re-forming element group to identify the anomaly components created by different types of mineralization processes; and finally,identifying ore-finding targets based on the anomaly components.This method is applied to the Tengchong tin-polymetallic belt to delineate ore-finding targets,where four targets for Sn(W)and three targets for Pb-Zn-Ag-Fe polymetallic mineralization are identified and defined as new areas for further prospecting.It is shown that BEMD combined with PCA can be applied not only in extracting the anomaly component for delineating the ore-finding target,but also in extracting the residual component for identifying its high background zone favorable for mineralization from its oreforming element group. 相似文献
48.
跨界族群以及由此造成的分离主义运动一直是民族学、社会学与国际关系等学科研究的重点议题。本研究对安哥拉卡宾达飞地分离主义运动的研究着重探讨特殊地理位置为安哥拉政府带来的治理困境。对卡宾达分离主义运动的发展历史进行回顾,发现跨界族群问题是卡宾达分离主义运动产生的根源,而飞地属性则从不同角度增加了安哥拉在治理该问题上的难度,主要表现为未能使当地人产生对安哥拉的国家认同,大幅降低了外部干涉难度以及难以满足该地居民的发展诉求。本研究还认为跨界族群的分离主义思潮看似合理,但其文化特殊性并不一定能转化为分离主义运动的政治合理性。虽然非洲国家很多现有边界存在不合理之处,但对它的改变未必能让跨界族群获得更好的社会经济发展。另外,边界对分离主义组织运行模式的影响也是一个值得深入研究的议题。 相似文献
49.
转型期广州市居民职住模式的群体差异及其影响因素 总被引:1,自引:0,他引:1
职住关系是城市研究领域重要的议题之一。体制改革后中国社会分层结构特殊,检验不同阶层居民在职住地选择偏好的差异,有助于理解居民职住格局形成的内部机制。利用广州市入户问卷调查、建成环境和人口普查等数据,采用两步聚类和多项logistic回归,对广州市居民进行阶层划分,对比居民职住模式的群体差异及其影响因素。结果表明:职住决策时,体制外工薪阶层追求低生活成本,受职住地建成环境影响显著;体制内阶层习惯于传统单位制下社会关系密切的社区,受邻里环境影响显著,还受个人属性影响;无固定工作者决策自由和平衡程度高,受少量建成环境因素影响。研究有助于了解居民职住格局形成的制度性机制,为优化居民职住格局提供思路。 相似文献
50.
北京公交就业可达性及其地区和人群差异 总被引:2,自引:0,他引:2
运用经济普查、人口普查数据和基于百度地图的公交出行时间数据,分析北京都市区基于公共交通的就业可达性及其在城市不同人群和地区间的差异。结果表明:北京都市区的居民可在60分钟内通过公共交通到达18.3%的都市区工作岗位,这比美国100个最大的都市区的平均就业可达性水平要高,接近于美国纽约都市区的就业可达性水平。同时,由于就业郊区化程度有限和以中心—放射式布局的公交网络,北京都市区内的公交就业可达性存在着巨大的区域差异,中心城区的就业可达性远远高于郊区。此外,人口居住的郊区化程度远远高于就业的郊区化程度,导致北京都市区宏观层面的职住不平衡。随着人口居住郊区化程度的提高,公共交通如何服务居住日益分散的人口,提高就业可达性,是一项巨大的挑战。研究还发现,由于城市中心区的大部分就业为高技术的就业岗位,因此高受教育程度人口能更多地享受目前公共交通系统的便利,而受教育程度低的人口和外来人口公交就业可达性较低。为解决弱势群体所面临的就业可达性的不平等问题,需要更多的规划与政策干预。 相似文献