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901.
The Atlas Mountains have been uplifted by two mechanisms: Cenozoic thickening of the crust and thinning of the mantle lithosphere due to a buoyant thermal anomaly, previously inferred by indirect criteria to have started some 15 Ma. Because crustal shortening‐related uplift and mantle‐related uplift affect the topography at different spatial scales, we use scattered direct surface evidence to clarify the palaeoelevation dynamics. Uplifted Messinian shallow marine sediments in the southern margin of the Saïss Basin and in the northern Middle Atlas, tilted Pliocene lacustrine deposits in the Saïss Basin and in the piedmont of the southern High Atlas and drainage‐network reorganization in the Saïss Basin underscore the long‐wavelength rock uplift of the Atlas domain of mantle origin. The low erosion of the aforementioned deposits indicates that such uplift is a true surface uplift that occurred in post‐Miocene times at a minimum rate ranging from 0.17 to 0.22 mm yr?1. 相似文献
902.
Dario Camuffo Antonio della Valle Chiara Bertolin Elena Santorelli 《Climatic change》2017,142(1-2):7-22
The observations taken in Bologna, Italy, from 1715 to 1815, three times a day, with a number of thermometers (i.e., Stancari air thermometers, Little Florentine thermometer, Florentine stick thermometer and a number of Réaumur spirit and mercury thermometers) some of them operating in parallel, have been recovered and analysed. The early thermometers had unknown scales and temperature units, with deviations due to the bulb shape or the thermometric liquid, but it is possible to interpret them after comparison between parallel readings. Historical sources and the analysis of the data fingerprints and their variability permit recognition of where instruments were located and who the observers were. It is also possible to relate the indoor climate of historical buildings to the outdoor one, and transform indoor readings as they were taken outdoors, expressed in Celsius. The Bologna series has been compared with the contemporary observations in Padua, Venice and Milano. The climate analysis shows that the temperature fluctuated but with an increasing trend. The 1730–1770 decades constituted the coldest period and 1980—today the warmest one. The eighteenth century was generally cold and had an impressive frequency of extremely severe winters that exceeded the rest of the series. The whole dataset (i.e. 1715–2015) of daily temperatures has been included to allow further use for scientific purposes. Finally, the paper provides a methodological example of procedures to recover and analyse early instrumental series. 相似文献
903.
José A. M. Demattê Julianne de Castro Oliveira Tiago Rodrigues Tavares Leonardo Ramirez Lopez Fabrício da Silva Terra Suzana Romeiro Araújo Caio Troula Fongaro Stoécio Malta Ferreira Maia Francisco Fujita de Castro Mello Rodnei Rizzo Simone Vicente Marco Antonio de Melo Bortolleto Pedro Henrique Ramos Cerqueira 《Environmental Earth Sciences》2016,75(18):1277
904.
Fernando A. López Mariano Matilla-García Jesús Mur Antonio Páez Manuel Ruiz 《Journal of Geographical Systems》2016,18(1):87-96
López et al. (Reg Sci Urban Econ 40(2–3):106–115, 2010) introduce a nonparametric test of spatial dependence, called SG(m). The test is claimed to be consistent and asymptotically Chi-square distributed. Elsinger (Reg Sci Urban Econ 43(5):838–840, 2013) raises doubts about the two properties. Using a particular counterexample, he shows that the asymptotic distribution of the SG(m) test may be far from the Chi-square family; the property of consistency is also questioned. In this note, the authors want to clarify the properties of the SG(m) test. We argue that the cause of the conflict is in the specification of the symbolization map. The discrepancies can be solved by adjusting some of the definitions made in the original paper. Moreover, we introduce a permutational bootstrapped version of the SG(m) test, which is powerful and robust to the underlying statistical assumptions. This bootstrapped version may be very useful in an applied context. 相似文献
905.
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908.
Claus Fröhlich José Romero Hansjörg Roth Christoph Wehrli Bo N. Andersen Thierry Appourchaux Vicente Domingo Udo Telljohann Gabrielle Berthomieu Philippe Delache Janine Provost Thierry Toutain Dominique A. Crommelynck André Chevalier Alain Fichot Werner Däppen Douglas Gough Todd Hoeksema Antonio Jiménez Maria F. Gómez José M. Herreros Teodoro Roca Cortés Andrew R. Jones Judit M. Pap Richard C. Willson 《Solar physics》1995,162(1-2):101-128
The scientific objective of the VIRGO experiment (Variability of solar IRradiance and Gravity Oscillations) is to determine the characteristics of pressure and internal gravity oscillations by observing irradiance and radiance variations, to measure the solar total and spectral irradiance and to quantify their variability over periods of days to the duration of the mission. With these data helioseismological methods can be used to probe the solar interior. Certain characteristics of convection and its interaction with magnetic fields, related to, for example, activity, will be studied from the results of the irradiance monitoring and from the comparison of amplitudes and phases of the oscillations as manifest in brightness from VIRGO, in velocity from GOLF, and in both velocity and continuum intensity from SOI/MDI. The VIRGO experiment contains two different active-cavity radiometers for monitoring the solar constant, two three-channel sunphotometers (SPM) for the measurement of the spectral irradiance at 402, 500 and 862 nm, and a low-resolution imager (LOI) with 12 pixels, for the measurement of the radiance distribution over the solar disk at 500 um. In this paper the scientific objectives of VIRGO are presented, the instruments and the data acquisition and control system are described in detail, and their measured performance is given.died 13 October 1994 相似文献
909.
Granulite rocks are exposed in eastern Minas Gerais, Brazil. Its early neoproterozoic evolution is characterised by a history of an active continental margin, including the accretion of suspect terranes. The Manhuaçu Terrane is one of those which is represented by a granitic continental plutonic arc and terrigeneous metasediments reflecting a continental margin. A metasedimentary gneiss belt at this margin with shallow to deep marine clastic lithologies as well as metavolcanic and metaplutonic mafic rocks was interpreted as an extensive tectonic segment with suspect development in a back-arc setting. Fragments of a volcanic arc are identified and interpreted as an evidence for a probable island-arc domain. The granulites occur as massive rocks as well as high-grade gneisses and show lithological, structural and metamorphic attributes consistent with their host belt type. In the western portion granulites derived from sedimentary protoliths, have been deposited, deformed and metamorphosed together with the mafic intrusions and as well as with their crystallization. Regional uplift exposed these rocks probably immediately after the metamorphism. In these belts the metamorphic grade is not uniform, especially where uplifting has exposed oblique cross sections over the granulitic rocks. Geothermobarometric calculations indicate that the granulites has been generated under T conditions between 800 and 990 ± 50 C and from medium (4.8 kb) to relatively high (10.0 kb) pressures. 相似文献
910.
Sara Villa Marco Vighi Valter Maggi Antonio Finizio Ezio Bolzacchini 《Journal of Atmospheric Chemistry》2003,46(3):295-311
The significance of persistent organic pollutants, such as organochlorine compounds, as global contaminants in cold regions has been recognised for a long time. In particular, there is a growing interest on the role of high mountains as `cold condensers' for these chemicals. In this paper, for the first time, organochlorine pesticides (DDTs, HCHs, HCB) are analysed in an ice core sampled on a `cold' glacier in the Alps. Several methods were applied to achieve accurate dating of the core layers. Historical trends of organochlorine pesticides from the 1950s up to the year 2000 are reconstructed, showing, for each individual chemical, the influence of long range transport, as well as of local transport patterns. The role of mountain glaciers as natural archives for studying the local and global transport of persistent organic pollutants is highlighted, though results can be biased by volatilisation losses. 相似文献