全文获取类型
收费全文 | 208篇 |
免费 | 3篇 |
专业分类
测绘学 | 1篇 |
大气科学 | 14篇 |
地球物理 | 61篇 |
地质学 | 56篇 |
海洋学 | 12篇 |
天文学 | 56篇 |
自然地理 | 11篇 |
出版年
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2014年 | 3篇 |
2013年 | 4篇 |
2011年 | 4篇 |
2010年 | 5篇 |
2009年 | 8篇 |
2008年 | 5篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 2篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 9篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 9篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1976年 | 2篇 |
1973年 | 4篇 |
1972年 | 2篇 |
1971年 | 4篇 |
1970年 | 4篇 |
1969年 | 2篇 |
1965年 | 3篇 |
1964年 | 3篇 |
1963年 | 3篇 |
1956年 | 2篇 |
1951年 | 1篇 |
1950年 | 1篇 |
1928年 | 2篇 |
排序方式: 共有211条查询结果,搜索用时 46 毫秒
1.
2.
3.
R. Von Herzen 《Applied Ocean Research》1985,7(3):175-176
4.
Several hundred H spectrograms from areas close to the solar limb were taken with the 35 cm Coudé refractor at Anacapri. The 41 spectra with the greatest spatial resolution were selected and analysed. At the supergranular boundaries a considerable fraction of the line profiles were found to correspond to Beckers Cloud Model (BCM). Moreover, the BCM parameters of the dark mottles at the limb appear to be approximately equal to those from the center of the disk. On the other hand, we also obtained evidence in disagreement with the general applicability of the BCM to all features of the chromospheric fine structure.We attempted to present the large set of observational data in a fashion that permits their interpretation by alternative theoretical models.Mitteilungen aus dem Fraunhofer Institut Nr. 151. 相似文献
5.
Potential of High-Resolution Satellite Data in the Context of Vulnerability of Buildings 总被引:1,自引:2,他引:1
High-resolution space-borne remote sensing data are investigated for their potential to extract relevant parameters for a
vulnerability analysis of buildings in European countries. For an evaluation of large earthquake scenarios, the number of
parameters in models for vulnerability is reduced to a minimum of relevant information such as the type of building (age,
material, number of storeys) and the geological and spatial context. Building-related parameters can be derived from remote
sensing data either directly (e.g. height) or indirectly based on the recognition of the urban structure type in which the
buildings are located. With the potential of a fully- or semi-automatic inventory of the buildings and their parameters, high-resolution
satellite data and techniques for their processing are a useful supporting tool for the assessment of vulnerability. 相似文献
6.
Between 1995 and 2001, 16 measuring points at small and medium sized brooks in the Harz National Parks were sampled. The samples have been evaluated by means of hydrochemistry and macroinvertebrate biology. Although nearly all streams are largely uncontaminated by oxygen-consuming substances, they are settled only by a small number of macroinvertebrate species. There is a clear correlation between this number and pH. The reduction in species number with decrease of pH is mainly caused by the absence of most Ephemeroptera, some Coleoptera and Trichoptera. Comparing biological evaluation of acidity with physico-chemical measurements, a unacceptable underestimation was found. The reason could be that different sensitivities to acidification between regional populations seem to exist.
Despite of the low species number, there is a very specific macroinvertebrate fauna that emphasizes the conservation value of the Harz National Parks. 相似文献
7.
8.
9.
Sibel Bargu Melissa M. Baustian Nancy N. Rabalais Ross Del Rio Benjamin Von Korff R. Eugene Turner 《Estuaries and Coasts》2016,39(5):1345-1356
The presence of domoic acid (DA) toxin from multiple species of Pseudo-nitzschia is a concern in the highly productive food webs of the northern Gulf of Mexico. We documented the Pseudo-nitzschia presence, abundance, blooms, and toxicity over three years along a transect ~100 km west of the Mississippi River Delta on the continental shelf. Pseudo-nitzschia were present throughout the year and occurred in high abundances (>104 cells l?1) in the early spring months during high Mississippi River (MSR) flow (~20,000 m3 s?1) but were most abundant (>106 cells l?1) when MSR discharge was relatively lower among the spring months. A high particulate toxin production (maximum reaching 13 μg DA l?1) was associated with the high cell abundances and exceeded, by an order of magnitude, prior reports of particulate DA concentrations in Louisiana coastal waters. Differences in Pseudo-nitzschia peak times and its toxicity were correlated mainly with the timing and magnitude of MSR discharge and changes in associated parameters such as nutrient stoichiometry and salinity. A negative relationship between high MSR discharge and Pseudo-nitzschia and particulate DA concentrations was documented. These riverine dynamics have the potential to influence DA contamination in pelagic and benthic food webs in the coastal waters of the northern Gulf of Mexico. 相似文献
10.