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131.
132.
Kuiper (1972) had suggested that the Great Red Spot (GRS) of Jupiter is a giant hurricane. We present further arguments in support of this idea and propose that it may also apply to the smaller vortices such as the white and brown ovals (barges). Our estimates indicate that the spin-down time-constants for these Jovian vortices are significantly shorter than the observed lifetimes. Thus, the motions must be sustained through the continued release of internal energy. In analogy with the CISK mechanism for the terrestrial hurricane, transport of water vapor, which is observed on Jupiter, may provide the latent energy to fuel the motions. The energy the planet emits must be transported upwards; therefore its troposphere should be convectively unstable. In such an atmosphere, the proposed solar driven meridional circulation is multicellular, of the Ferrel-Thomson type. If the energy transport from the planetary interior is accelerated by the upward motions in the circulation, eastward zonal jets develop such as observed in the equatorial region. But if the upward flow of energy is impeded by the prevailing downward motions in the meridional circulation (which occur, for example, near 20 latitude), we propose that the convective instability is amplified. The conditions then are more favorable for the development of hurricanes which may appear in the form of the GRS and the white and brown ovals. The GRS with its large size and long life time (indicating that it is very deep) is unique, and we suggest that it may have been induced by meteor impact. 相似文献
133.
Julie C. Libarkin Anne U. Gold Sara E. Harris Karen S. McNeal Ryan P. Bowles 《Climatic change》2018,150(3-4):403-416
The relationship between climate change understanding and other variables, including risk perception, beliefs, and worldviews, is an important consideration as we work to increase public attention to climate change. Despite significant effort to develop rigorous mechanisms for measuring affective variables, measurement of climate change understanding is often relegated to unvalidated questions or question sets. To remedy this situation, we constructed and analyzed a climate change concept inventory using a suite of validity and reliability steps, including Rasch analysis. The resultant 21-item test has a high degree of validity and reliability for measuring understanding about basic climate change processes. Inventory scores along with other variables were included in a model of climate change risk perception, providing both concurrent validity for the test and new insight into the importance of understanding, worldview, and values on risk perception. We find that environmental beliefs and cultural cognition worldview play a larger role in predicting an individual’s risk perception than knowledge. Implications for addressing climate change are considered. 相似文献
134.
Chauncy D. Harris 《The Professional geographer》1997,49(2):245-256
Geographers in Washington, DC, during World War II and the agencies in which they worked are recalled through the naming of geographers engaged in wartime work during this seminal period in the development of the geography profession in the United States. The five agencies then employing the largest number of geographers were the Research and Analysis Branch of the Office of Strategic Services, the Topographic Branch of the Military Intelligence Division of the War Department, the Board of Economic Warfare (later the Foreign Economic Administration), the Board on Geographic Names, and the Office of the Geographer, Department of State. The impacts of this period on individual geographers, the professional organization of geographers, cartography, higher education, and the government are suggested. 相似文献
135.
136.
G. W. Harris D. Klemp T. Zenker J. P. Burrows B. Mathieu 《Journal of Atmospheric Chemistry》1992,15(3-4):315-326
Measurements of NO2, HCHO, and H2O2 were made by the highly specific method of mid infra-red absorption spectroscopy using tunable diode lasers (TDLAS) during the 1988 Polarstern expedition. The TDLAS data are compared to those obtained during the cruise using less direct methods. Southern Hemisphere NO2 levels suggest nett photochemical destruction of O3 in the boundary layer. Northern Hemisphere HCHO averaged 0.47±0.2 ppbv; the HCHO measurements are used in a simple calculation to estimate OH noontime maxima of 3–6×106 cm-3. 相似文献
137.
138.
Chris Harris Brian R Watters P Bruce Groenewald 《Contributions to Mineralogy and Petrology》1991,107(1):100-111
Regional dolerite dykes of Mesozoic age in western Dronning Maud Land are variable in both major and trace element composition
and include picritic types (MgO>18 wt%). The range in incompatible element concentrations is considerable (e.g. Zr 40–478
ppm) and shows little correlation with MgO content. Both high-and low-Ti, Zr (HTZ and LTZ) magma types are present and there
is a spread of compositions between these types. Major element oxide variations in dykes having MgO>10 wt% indicate that olivine
and orthoyproxene fractionation occurred, presumably at an early high-pressure stage of magma evolution. Major element oxide
variations in dykes having MgO<10 wt% indicate control by olivine and clinopyroxene. A minority of the more evolved dykes
are compositionally similar to the nearby Kirwan basalts, but the majority cannot be related to the Kirwan basalts by any
simple petrogenetic process as they contain higher concentrations of incompatible elements and have higher Mg-numbers. The
HTZ Dronning Maud Land dolerites have incompatible trace element concentrations which are very similar to the HTZ basalt magma
types of the Karoo of southern Africa with the exception of lower K and Rb in DML dolerites. The HTZ dolerites occur in the
part of Dronning Maud Land which appears to have been tectonically stable since the Archaean and are not found to intrude
the surrounding high-grade (about 1000 Ma) metamorphic rocks of the Sverdrup Group. These data provide qualified support for
models which seek to relate spatially the HTZ Mesozoic basalt types of Gondwana to sources beneath stable Archaean cratons. 相似文献
139.
Carbonic fluid inclusions in South Indian granulites: evidence for entrapment during charnockite formation 总被引:1,自引:0,他引:1
M. Santosh D. H. Jackson N. B. W. Harris D. P. Mattey 《Contributions to Mineralogy and Petrology》1991,108(3):318-330
Field evidence and fluid inclusion studies on South Indian incipient charnockites suggest that charnockite formation occurred
during a decompressional brittle regime following the ‘peak’ of metamorphism and regional deformation. The most abundant type
of inclusions in quartz and garnet grains in these charnockites contain high-density carbonic fluids, although lower-density
fluids occur in younger arrays of inclusions. Discrete fluid inclusion generations optically are observed to decrepitate over
well-defined temperature intervals, and quantitative measurements of CO2 abundance released from these inclusions by stepped thermal decrepitation show up to a four-fold increase (by volume) in
the incipient charnockites relative to the adjacent gneisses from which they are derived. Studies based on optical thermometry,
visual decrepitation and stepped-heating inclusion release together indicate that entrapment of carbonic fluids coincided
with charnockite formation. We confirm that an influx of carbon dioxide-rich fluids is associated with the amphibolite-granulite
transition, as recorded by the incipient charnockites, the remnants of which are commonly preserved as the earliest generation
of high-density fluid inclusions. 相似文献
140.
A new multidimensional scaling (MS) technique, referred to as the Pijk model, is formulated on the basis of associations among triple objects (samples or variables), instead of pairs of objects as used in the usual MS methods, such as factor analysis. The computational scheme provided for this method is the reduction of an original problem to a standard eigenvalue-eigenvector problem. The major goal of the technique is simplification and reduction of data structures and the rescaling of original objects into a new and reduced space, so that patterns and relations of the original objects can be conventiently examined in two-dimensional “factor” plots. The Pïjk method is illustrated and tested by using a set of geochemical data related to the epithermal gold and silver vein deposits in the Walker Lake quadrangle of Nevada and California. The characteristics of element associations suggested in the Pijk analysis are consistent with field observations. A preliminary comparison between the new method and the ordinary factor analysis also is made on the basis of the same data set. Results are encouraging in that analysis by the Pijk model captures triple-object associations that might be missed by the ordinary factor analysis which considers only pair-variable correlations 相似文献