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321.
S. V. Jeffers A. Collier Cameron J. R. Barnes J. P. Aufdenberg 《Astrophysics and Space Science》2006,304(1-4):371-373
We have used spectrophotometric data from nine Hubble Space Telescope orbits to eclipse-map the primary component of the RS CVn binary SV Cam. From these observations and its HIPPARCOS parallax we find that the surface flux in the eclipsed low-latitude region is about 30 % lower than computed from the best fitting PHOENIX model atmosphere. This flux deficit can only be accounted for if about a third of the primary's surface is covered with unresolved spots. Even when we extend the spottedness from the eclipsed region to the entire surface, there still remains an unaccounted flux deficit. This remaining flux deficit is explained by the presence of a large polar spot extending down to latitude 42 ±6 °.Marie Curie Intra-European Fellow 相似文献
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D. M. Bramich Keith Horne I. A. Bond R. A. Street A. Collier Cameron B. Hood J. Cooke D. James T. A. Lister D. Mitchell K. Pearson A. Penny A. Quirrenbach N. Safizadeh Y. Tsapras 《Monthly notices of the Royal Astronomical Society》2005,359(3):1096-1116
We present results from 30 nights of observations of the open cluster NGC 7789 with the Wide Field Camera on the Isaac Newton Telescope, La Palma. From ∼900 epochs, we obtained light curves and Sloan r '− i ' colours for ∼33 000 stars, with ∼2400 stars having better than 1 per cent precision. We expected to detect ∼2 transiting hot Jupiter planets if 1 per cent of stars host such a companion and a typical hot Jupiter radius is ∼1.2 R J . We find 24 transit candidates, 14 of which we can assign a period. We rule out the transiting planet model for 21 of these candidates using various robust arguments. For two candidates, we are unable to decide on their nature, although it seems most likely that they are eclipsing binaries as well. We have one candidate exhibiting a single eclipse, for which we derive a radius of 1.81+0.09 −0.00 R J . Three candidates remain that require follow-up observations in order to determine their nature. 相似文献
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Y. C. Unruh J.-F. Donati J. M. Oliveira A. Collier Cameron C. Catala H. F. Henrichs C. M. Johns-Krull B. Foing J. Hao H. Cao J. D. Landstreet H. C. Stempels J. A. de Jong J. Telting N. Walton P. Ehrenfreund A. P. Hatzes J. E. Neff T. Böhm T. Simon L. Kaper K. G. Strassmeier Th. Granzer 《Monthly notices of the Royal Astronomical Society》2004,348(4):1301-1320
328.
Scott C. Sheridan Cameron C. Lee Michael J. Allen Laurence S. Kalkstein 《Climatic change》2012,115(2):291-309
Excessive heat significantly impacts the health of Californians during irregular but intense heat events. Through the 21st century, a significant increase in impact is likely, as the state experiences a changing climate as well as an aging population. To assess this impact, future heat-related mortality estimates were derived for nine metropolitan areas in the state for the remainder of the century. Here in Part I, changes in oppressive weather days and consecutive-day events are projected for future years by a synoptic climatological method. First, historical surface weather types are related to circulation patterns at 500mb and 700mb, and temperature patterns at 850mb. GCM output is then utilized to classify future circulation patterns via discriminant function analysis, and multinomial logistic regression is used to derive future surface weather type at each of six stations in California. Five different climate model-scenarios are examined. Results show a significant increase in heat events over the 21st century, with oppressive weather types potentially more than doubling in frequency, and with heat events of 2?weeks or longer becoming up to ten times more common at coastal locations. 相似文献
329.
Jan Cameron 《新西兰海洋与淡水研究杂志》2013,47(4):431-444
The presence and degree of pollution in the Heathcote River was estimated from bacterial and chemical analyses of water sampled at low tide from five stations in summer 1967–68. The river is very badly polluted in the industrial area and downstream of it, but is fairly clean upstream of the industrial area. Results of analyses of micro‐organisms and macrofauna at 20 stations are presented and distributions of these organisms are related to salinity and pollution in the river. Pollution is restricting the macrofauna of the river but is encouraging micro‐organism populations. Three groups of macrofauna are present:
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Those present in clean freshwater only,
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Those tolerating pollution but restricted to freshwater, and
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Those tolerating pollution but restricted to saline water.
330.
M. A. Barstow M. P. Kowalski R. G. Cruddace K. S. Wood F. Auchere N. J. Bannister M. F. Bode G. E. Bromage M. R. Burleigh A. C. Cameron A. Cassatella F. Delmotte J. G. Doyle B. Gaensicke B. Gibson C. S. Jeffery C. Jordan N. Kappelmann R. Lallement J. S. Lapington D. de Martino S. A. Matthews M. Orio E. Pace I. Pagano K. J. H. Phillips M.-F. Ravet J. H. M. M. Schmitt B. Y. Welsh K. Werner G. Del Zanna 《Experimental Astronomy》2009,23(1):169-191
This paper describes a proposed high resolution soft X-ray and Extreme Ultraviolet spectroscopy mission to carry out a survey
of Stellar and Galactic Environments (SAGE). The payload is based on novel diffraction grating technology which has already
been proven in a sub-orbital space mission and which is ready to fly on a satellite platform with minimal development. We
discuss the goals of a SAGE base-line mission and demonstrate the scientific importance of high resolution spectroscopy in
the Extreme Ultraviolet for the study of stars and the local interstellar medium. 相似文献