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21.
22.
Yasuyuki Tsujino Yasunari Shigeta Haruyoshi Maeda Toshifumi Komatsu Nao Kusuhashi 《Island Arc》2013,22(4):549-561
Discovery of Sirenites senticosus (Dittmar) in the upper part of the Sabudani Formation of the Kurosegawa Belt, Kito area, Tokushima Prefecture, Japan, establishes a late Early Carnian age for this part of the stratigraphic unit. Because S. senticosus was mainly distributed in the Tethyan region, its occurrence provides evidence that Late Triassic ammonoids of Japan had strong affinities with those of the Tethyan faunas. This finding clearly differs from the biogeographic distribution of contemporary bivalves in the region, which are referred to as the Kochigatani bivalve faunas, and show strong affinities to faunas of the Boreal region. 相似文献
23.
Yosuke Maeda 《Geoforum》2012,43(2):342-352
The recent development of the third sector and the government encouragement of it have attracted the attention of many researchers. In particular, geographical research has examined how the third sector has been affected or changed by government policies or guidelines in recent political economic contexts, especially neo-liberalism and also neo-communitarianism. While much research has demonstrated that the relationship between the government and the third sector is becoming closer, and has considered the problematic impact on the sector or the community, recent studies have described a much more complicated relationship and its consequence. In response, this paper attempts to explore alternative effects of government encouragement at the local community level, through utilising empirical data on recent voluntary activity regarding community safety by the Voluntary Organisations for Crime Prevention Patrol (VOCPP) in Musashino City, a suburb of Tokyo in Japan. Before focusing on the case study in Musashino, the paper briefly outlines key geographical literature on the third sector, and also examines recent expectations of Japan’s third sector using Japanese political documents. Finally, the paper argues that the encouragement of government in fact has the potential to work as a ‘catalyst’ leading to a more independent third sector, with a geographically and organisationally less hierarchical structure, and may also assist in developing a more diversified community. 相似文献
24.
Cheol-Hee Kim Lim-Seok Chang Jeong-Soo Kim Fan Meng Mizuo Kajino Hiromasa Ueda Yuanhang Zhang Hye-Young Son Youjiang He Jun Xu Keiichi Sato Chang-Keun Song Soo-Jin Ban Tatsuya Sakurai Zhiwei Han Lei Duan Suk-Jo Lee Shang-Gyoo Shim Young Sunwoo Tae-Young Lee 《Asia-Pacific Journal of Atmospheric Sciences》2011,47(4):399-411
Three comprehensive acid deposition models were used to simulate the sulfur concentrations over northeast Asia over the period covering entire year of 2002, and discussed the aggregated uncertainties and discrepancies of the three models. The participating models are from the countries participating in the project of Longrange Transboundary Air Pollutants in Northeast Asia (LTP): China, Japan and Korea. The Eulerian Model-3/CMAQ (by China), Regional Air Quality Model (RAQM, by Japan), and Comprehensive Acid Deposition Model (CADM, by Korea) were employed by each country with common emissions data established by the administrative agencies of China, Japan and Korea. The episodic simulation results between 1 to 15, March 2002 are also presented, during which aircraft measurements were carried out over the Yellow sea. The episodic results show both a wide short-term variability in simulations against measurements, and maximum concentration differences of 3~5 times among the three models, requiring that further attention before confidence among the three models can be claimed for short-term simulations. However, the year-long cumulative simulations showed almost the same general features, with lower aggregated uncertainties between the three models, produced by the long term integration over northeast Asia. 相似文献
25.
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
26.
Marine aerosols in the western North Pacific were collected using a cascade impactor. Size-separated aerosols were analyzed for organic carbon, alkanes and polycyclic aromatic hydrocarbons (PAH). The results showed that the rate of decrease of the atmospheric concentrations of these organic components with increase in distance from Japan as well as from the coast of the Eurasian Continent was in the order PAHalkanes>organic carbon. The bulk of all these organic components occurred in the smallest size fraction of particles (<1m). Analysis of the alkanes and PAH indicated that the hydrocarbons in aerosols in Japanese coastal marine areas are primarily derived from terrestrial anthropogenic sources which also contribute to a lesser extent to aerosols in marine areas about 1,000 km off the coast of Japan. In remote marine areas the hydrocarbons on small particles (<1m) have principally a natural terrestrial origin while those on larger particles are marine in origin. 相似文献
27.
Insaf S. Babiker Mohamed A. A. Mohamed Kaori Komaki Keiichi Ohta Kikuo Kato 《Journal of Oceanography》2004,60(3):553-562
Changes in patterns of undetectability and molar ratios of dissolved nutrients in the euphotic zone of the oligotrophic western
North Atlantic Ocean were investigated utilizing the Bermuda Atlantic Time-series Study (BATS) data set of the US Joint Global
Ocean Flux Study (JGOFS). Our aim was to examine the temporal dynamics of nutrient stocks over a decade (1989∼1998) and to
gain insight into the interactions between the different biotic and abiotic factors underlying BATS. Patterns of nutrient
undetectability clearly revealed the depleted nature of the nutrients in surface water at the BATS location, particularly
phosphorous. The N:P ratio was consistently far above the nominal Redfield ratio (mean, 38.5) but was significantly lower
during the 1993∼1994 period (22.1). Over the same period the proportion of samples depleted in N only increased while the
proportion of samples depleted in P only decreased. This indicates an overall reduction of N relative to P in the surface
water at BATS during the 1993∼1994 period, the reasons for this anomaly, though, are not clear. The correlation analysis between
the biotic and abiotic variables at BATS has indicated some interesting relationships that can help understand some of the
parameters affecting nutrient stocks in the euphotic zone and their consequent impacts on marine biota. Although nutrient
stocks in the oligotrophic environment are limited, they might be subject to interannual variation that may become anomalous
in some cases. These variations might underlay significant feedback mechanisms by affecting marine productivity, the prime
factor controlling the sequestration of atmospheric CO2 by the oceans.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
28.
Maeda Sonosuke 《Journal of Oceanography》1972,28(3):126-130
29.
Geographical distributions of upwelling centers off the coast of Peru are studied on the basis of monthly mean wind data during
17 years from 1939 through 1955. Three remarkable upwelling centers are found near 5°S, 11°S and 15°S, from the analyses.
With regard to the negative surface divergence found in the offing of Huacho-Callao (near 11°S) in August, it is pointed out
that a local high pressure cell is generated in the atmosphere. 相似文献
30.
Innovative applications of capillary zone electrophoresis (CZE) to the determination of inorganic ions in environmental aquatic samples of high salinity and, particularly, in seawater are reviewed. Emphasis is placed on advanced approaches utilized for securing separation performance from being degraded by the presence of matrix salts and for simultaneous separation of ions different in natural abundance. Also covered are methodologies of present or possible use to evolve the method's practical utility to trace-level ions. Surveyed procedures are tabulated for the purpose of facilitating the method selection or further development. In addition, brief background information on basic methodological principles of CZE in inorganic ion analysis is given for a better orientation of those intending or just beginning to put CZE to work. Finally, possible future research trends and developments of CZE in the area are briefly discussed. 相似文献