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91.
T. Kosugi K. Matsuzaki T. Sakao T. Shimizu Y. Sone S. Tachikawa T. Hashimoto K. Minesugi A. Ohnishi T. Yamada S. Tsuneta H. Hara K. Ichimoto Y. Suematsu M. Shimojo T. Watanabe S. Shimada J. M. Davis L. D. Hill J. K. Owens A. M. Title J. L. Culhane L. K. Harra G. A. Doschek L. Golub 《Solar physics》2007,243(1):3-17
The Hinode satellite (formerly Solar-B) of the Japan Aerospace Exploration Agency’s Institute of Space and Astronautical Science (ISAS/JAXA) was successfully launched
in September 2006. As the successor to the Yohkoh mission, it aims to understand how magnetic energy gets transferred from the photosphere to the upper atmosphere and results
in explosive energy releases. Hinode is an observatory style mission, with all the instruments being designed and built to work together to address the science
aims. There are three instruments onboard: the Solar Optical Telescope (SOT), the EUV Imaging Spectrometer (EIS), and the
X-Ray Telescope (XRT). This paper provides an overview of the mission, detailing the satellite, the scientific payload, and
operations. It will conclude with discussions on how the international science community can participate in the analysis of
the mission data.
T. Kosugi deceased 26 November 2006. 相似文献
92.
1 IntroductionSnowdensificationiscriticalforcalculationsinengineering glaciology,snowavalancheforecasting ,springflooding,andotherpracticalaspects.Itisalsoimportantforinterpretingicecoredataincludingthosetakenfromratherwarmsiteswheresurfacelay ersexperiencemelting ,sinceitwouldaffectthechangeofannuallayerthicknesswithtime.Whileextensivestudies(e.g .AndersonandBenson 1 963 ;Bader1 960 ,1 962 ;Koji ma 1 95 4,1 95 5 ,1 95 6,1 95 7,1 95 8,1 95 9,1 964;Keeler 1 967;Gow 1 975 ;MaenoandE binuma 1… 相似文献
93.
Fernando Shinji Kawakubo Rubia Gomes Morato Carmen Lucia Midaglia Maria Lucia Cereda Gomide Ailton Luchiari 《国际地球制图》2013,28(2):165-175
A spectral linear-mixing model using Landsat ETM+ imagery was undertaken to estimate fraction images of green vegetation, soil and shade in an indigenous land area in the state of Mato Grosso in the central-western region of Brazil. The fraction images were used to classify different types of land use and vegetation cover. The fraction images were classified by the following two methods: (a) application of a segmentation based on the region-growing technique; and (b) grouping of the regions segmented using the per-region unsupervised classifier named ISOSEG. Adopting a 75% threshold, ISOSEG generated 44 clusters that were grouped into eight land-use and vegetation-cover classes. The mapping achieved an average accuracy of 83%, showing that the methodology is efficient in mapping areas of great land-use and vegetation-cover diversity, such as that found in the Brazilian cerrado (savanna). 相似文献
94.
Sarata K. Sahoo Masahiro Hosoda Ganesh Prasad Hiroyuki Takahashi Atsuyuki Sorimachi Tetsuo Ishikawa Shinji Tokonami Shigeo Uchida 《Acta Geophysica》2013,61(4):876-885
The activity concentrations of 226Ra and 228Ac in weathered Japanese soils from two selected prefectures have been measured using a γ-ray spectroscopy system with high purity germanium detector. The uranium, thorium, and rare earth elements (REEs) concentrations were determined from the same soil samples using inductively coupled plasma mass spectrometry (ICP-MS). For example, granitic rocks contain higher amounts of U, Th, and light REEs compared to other igneous rocks such as basalt and andesites. Therefore, it is necessary to understand the interaction between REEs and nature of soils since soils are complex heterogeneous mixture of organic and inorganic solids, water, and gases. In this paper, we will discuss about distribution pattern of 238U and 232Th along with REEs in soil samples of weathered acid rock (granite) collected from two prefectures of Japan: Hiroshima and Miyagi. 相似文献
95.
Jung Eun Lim Mahtab Ahmad Sang Soo Lee Christopher L. Shope Yohey Hashimoto Kwon‐Rae Kim Adel R. A. Usman Jae E. Yang Yong Sik Ok 《洁净——土壤、空气、水》2013,41(12):1235-1241
Low cost lime‐based waste materials have recently been used to immobilize metals in contaminated soils. This study was conducted to evaluate the effects of oyster shells and eggshells as lime‐based waste materials on immobilization of cadmium (Cd) and lead (Pb) in contaminated soil, as well as their effects on metal availability to maize plants (Zea mays L.). Oyster shells and eggshells were applied to soils at 1 and 5% w/w, after which they were subject to 420 days of incubation. The toxicity characteristic leaching procedure (TCLP) test was employed to determine the mobility of Cd and Pb in soils. The results showed that the addition of waste materials effectively reduced the metal mobility as indicated by the decrease in the concentration of TCLP‐extractable Cd and Pb, and this was mainly due to significant increases in soil pH (from 6.74 in untreated soil to 7.85–8.13 in treated soil). A sequential extraction indicated that the addition of such alkaline wastes induced a significant decline in the concentration of Cd in the exchangeable fraction (from 23.64% in untreated soil to 1.90–3.81% in treated soil), but it increased the concentration of Cd in the carbonate fraction (from 19.59% in untreated soil to 36.66–46.36% in treated soil). In the case of Pb, the exchangeable fraction was also reduced (from 0.67% in untreated soil to 0.00–0.01% in treated soil), and the fraction of Pb bound to carbonate was slightly increased (from 16.61% in untreated soil to 16.41–18.25% in treated soil). Phytoavailability tests indicated that the metal concentrations in the shoots of maize plant were reduced by 63.39–77.29% for Cd and by 47.34–75.95% for Pb in the amended soils, with no significant differences being observed for the amendment types and the application rates. Overall, these results indicate that oyster shells and eggshells can be used as low cost lime‐based amendments for immobilizing Cd and Pb in contaminated soils. 相似文献
96.
The abundance of HDO above the clouds in the dayside atmosphere of Venus was measured by ground-based 2.3 μm spectroscopy over 4 days. This is the first HDO observation above the clouds in this wavelength region corresponding to a new height region. The latitudinal distributions found show no clearly defined structure. The disk-averaged mixing ratio is 0.22 ± 0.03 ppm for a representative height region of 62–67 km. This is consistent with measurements found in previous studies. Based on previous H2O measurements, the HDO/H2O ratio is found to be 140 ± 20 times larger than the telluric ratio. This lies between the ratios of 120 ± 40 and 240 ± 25, respectively, reported for the 30–40 km region by ground-based nightside spectroscopy and for the 80–100 km region by solar occultation measurement on board the Venus Express. 相似文献
97.
98.
The first crater of Nakadake, peak of Aso volcano, Japan, contains a hot water lake that shows interesting variations in water
level and temperature. These variations were discovered by precise, continuous observations of the lake independent of precipitation.
We developed a numerical model of a hot crater lake and compared with observational data for the period from July 2006 to
January 2009. The numerical model revealed seasonal changes in mass flux (75–132 kg/s) and enthalpy (1,840–3,030 kJ/kg) for
the fluid supplied to the lake. The relation between the enthalpy and mass flux indicates that the bottom input fluid is a
mixture of high- and low-temperature fluids. Assuming a mixture of high-temperature steam at 800°C and liquid water at 100°C,
we evaluated the liquid and steam fluxes. The liquid water flux shows a seasonal increase lagging behind the rainy season
by 2 months, suggesting that the liquid water is predominantly groundwater. The fluctuation pattern in the flux of the high-temperature
steam shows a relation with the amplitude of volcanic tremor, suggesting that heating of the hydrothermal system drives the
tremor. Consequently, precise observations of a hot crater lake represent a potential method of monitoring volcanic hydrothermal
systems in the shallow parts of the volcanoes. 相似文献
99.
Shinji Ohsawa Kenji Sugimori Hiroshi Yamauchi Tomoyuki Koeda Hiroaki Inaba Yoshihisa Kataoka Tsuneomi Kagiyama 《Bulletin of Volcanology》2014,76(5):1-10
A drastic change in lake water color from blue-green to brown was observed in the summit crater lake of Mt. Shinmoe-dake, Kirishima Volcano about 8 months after its 2008 eruption. The color change lasted for about 2 months (April–June 2009). The discoloration was attributed to a brownish color suspension that had formed in the lake water. X-ray fluorescence and Fourier transform infrared analyses of a sample of the suspension identified schwertmannite (Fe8O8(OH)6(SO4)). A cultivation test of iron-oxidizing bacteria for the sampled lake water with lakebed sediment revealed that the crater lake hosts iron-oxidizing bacteria, which likely participated in schwertmannite formation. We suggest that pyrite (FeS2) provided an energy source for the iron-oxidizing bacteria since the mineral was identified in hydrothermally altered tephra ejected by the August 2008 eruption. From consideration of these and other factors, the brownish discoloration of the summit crater lake of Mt. Shinmoe-dake was inferred to have resulted from a combined volcanic–microbial process. 相似文献
100.
The abundance of carbon monoxide in the Venus’ dayside atmosphere above the clouds was measured by ground-based 2.3 μm spectroscopy for 4 days. The hemispherical distributions found show no significant latitudinal or longitudinal structure. The disc-averaged mixing ratio of 58 ± 17 ppm found at a representative height of 62-67 km is consistent with previous measurements. Such a flat distribution of CO abundance above the clouds seems to be controlled by an efficient horizontal eddy diffusion with a time scale of 30 days or shorter although the CO distribution below the clouds seems to be controlled by the meridional circulation. The pole-ward wind speed of the meridional circulation above the clouds is estimated to be 0.2 m s−1 or less based on the difference between the CO mixing ratios above and below the clouds. 相似文献