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991.
Martynova Yu. V. Krupchatnikov V. N. Gochakov A. V. Antokhina O. Yu. 《Izvestiya Atmospheric and Oceanic Physics》2022,58(1):95-109
Izvestiya, Atmospheric and Oceanic Physics - The relationship between the anomalies of the intensity of snow cover formation in Western Siberia (WS) and thermodynamic state of the atmosphere of... 相似文献
992.
R. Len L. Somoza C.J. Gimnez-Moreno C.J. Dabrio G. Ercilla D. Praeg V. Díaz-del-Río M. Gmez-Delgado 《Marine and Petroleum Geology》2009,26(8):1564-1579
This paper presents a computational model for mapping the regional 3D distribution in which seafloor gas hydrates would be stable, that is carried out in a Geographical Information System (GIS) environment. The construction of the model is comprised of three primary steps, namely: (1) the construction of surfaces for the various variables based on available 3D data (seafloor temperature, geothermal gradient and depth-pressure); (2) the calculation of the gas function equilibrium functions for the various hydrocarbon compositions reported from hydrate and sediment samples; and (3) the calculation of the thickness of the hydrate stability zone. The solution is based on a transcendental function, which is solved iteratively in a GIS environment.The model has been applied in the northernmost continental slope of the Gulf of Cadiz, an area where an abundant supply for hydrate formation, such as extensive hydrocarbon seeps, diapirs and fault structures, is combined with deep undercurrents and a complex seafloor morphology. In the Gulf of Cadiz, the model depicts the distribution of the base of the gas hydrate stability zone for both biogenic and thermogenic gas compositions, and explains the geometry and distribution of geological structures derived from gas venting in the Tasyo Field (Gulf of Cadiz) and the generation of BSR levels on the upper continental slope. 相似文献
993.
Dissolved aluminium and the silicon cycle in the Arctic Ocean 总被引:1,自引:0,他引:1
Concentrations of dissolved (0.2 µm filtered) aluminium (Al) have been determined for the first time in the Eurasian part of the Arctic Ocean over the entire water column during expedition ARK XXII/2 aboard R.V. Polarstern (2007). An unprecedented number of 666 samples was analysed for 44 stations along 5 ocean transects. Dissolved Al in surface layer water (SLW) was very low, close to 1 nM, with lowest SLW concentrations towards the Canadian part of the Arctic Ocean and higher values adjacent to and in the shelf seas. The low SLW concentrations indicate no or little influence from aeolian dust input. Dissolved Al showed a nutrient-type increase with depth up to 28 nM, but large differences existed between the different deep Arctic basins. The differences in concentrations of Al between water masses and basins could largely be related to the different origins of the water masses. In the SLW and intermediate water layers, Atlantic and Pacific inflows were of importance. Deep shelf convection appeared to influence the Al distribution in the deep Eurasian Basin. The Al distribution of the deep Makarov Basin provides evidence for Eurasian Basin water inflow into the deep Makarov Basin. A strong correlation between Al and Silicon (Si) was observed in all basins. This correlation and the nutrient-like profile indicate a strong biological influence on the cycling and distribution of Al. The biological influence can be direct by the incorporation of Al in biogenic silica, indirect by preferential scavenging of Al onto biogenic siliceous particles, or by a combination of both processes. From the slope of the overall Al–Si relationship in the intermediate water layer (AIDW; ~ 200–2000 m depth), an Al/Si ratio of 2.2 atoms Al per 1000 atoms Si was derived. This ratio is consistent with the range of previously reported Al/Si uptake ratio in biogenic opal frustules of diatoms. In the deepest waters (>2000 m depth) a steeper slope of the Al–Si relationship of 7.4 to 13 atoms Al per 1000 atoms Si likely results from entrainment of cold shelf water into the deep basins, carrying the signal of dissolution of terrigenous particles with a much higher Al:Si ratio of crustal abundance. Only a small enrichment with such crustal Al and Si component may readily account for the higher Al:Si slope in the deepest waters. 相似文献
994.
Taro Takahashi Stewart C. Sutherland Rik Wanninkhof Colm Sweeney Richard A. Feely David W. Chipman Burke Hales Gernot Friederich Francisco Chavez Christopher Sabine Andrew Watson Dorothee C.E. Bakker Ute Schuster Nicolas Metzl Hisayuki Yoshikawa-Inoue Masao Ishii Takashi Midorikawa Yukihiro Nojiri Arne Krtzinger Tobias Steinhoff Mario Hoppema Jon Olafsson Thorarinn S. Arnarson Bronte Tilbrook Truls Johannessen Are Olsen Richard Bellerby C.S. Wong Bruno Delille N.R. Bates Hein J.W. de Baar 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(11):2075-2076
995.
对虾传染性肌肉坏死病(infectious myonecrosis,IMN)最初于2002年8月爆发于巴西Piaui州的凡纳滨对虾(Litopenaeus vannamei)养殖场,并很快在巴西东北沿岸蔓延开来,目前已传至亚洲.2004年,经美国亚利桑那大学(University of Arizona)水产病害实验室研究,该病为一种新的对虾疾病,根据其症状,暂定名为传染性肌肉坏死病. 相似文献
996.
An improved method of two-dimensional kinematical structural analysis of tides (the “method of the orbits”) is presented.
This method allows us to determine the parameters of the primary tidal waves shaping the observed tidal structure. The construction
of the vertical orbits for the individual tidal harmonics is performed along the horizontal coordinate axes; one of them is
oriented along the so-called “reactive azimuth,” which coincides with the direction of the tidal current at the instant of
the zero tidal level. In this case, the orbit parameters include information on the amplitude-phase relations of the interfering
waves and allow us to determine the angle of the waves crossing. The suggested method enables us to quantitatively describe
the mechanism of the tidal formation with oblique interference both close to the shore and in the open sea. We tested the
new method in two local zones of the White Sea (Morzhovets Island and in the vicinity of the entrance to Kandalaksha Gulf)
where the presence of rotating semidiurnal tidal currents evidences the significant role of oblique interference of tidal
waves. In these zones, the developed method made it possible to perform a detailed quantitative analysis of the local tide
structure caused by the M2 tidal wave, which plays the dominant role in the White Sea. The result describes the structure of the propagation of the
primary tidal waves better than the field of “pure” energy fluxes that was used earlier. 相似文献
997.
K. E. Muryshev A. V. Eliseev I. I. Mokhov N. A. Diansky 《Izvestiya Atmospheric and Oceanic Physics》2009,45(4):416-433
A new version of the Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS), climate model (CM) has been
developed using an ocean general circulation model instead of the statistical-dynamical ocean model applied in the previous
version. The spatial resolution of the new ocean model is 3° in latitude and 5° in longitude, with 25 unevenly spaced vertical
levels. In the previous version of the oceanic model, as in the atmospheric model, the horizontal resolution was 4.5° in latitude
and 6° in longitude, with four vertical levels (the upper quasi-homogeneous layer, seasonal thermocline, abyssal ocean, and
bottom friction layer). There is no correction for the heat and momentum fluxes between the atmosphere and ocean in the new
version of the IAP RAS CM. Numerical experiments with the IAP RAS CM have been performed under current initial and boundary
conditions, as well as with an increasing concentration of atmospheric carbon dioxide. The main simulated atmospheric and
oceanic fields agree quite well with observational data. The new version’s equilibrium temperature sensitivity to atmospheric
CO2 doubling was found to be 2.9 K. This value lies in the mid-range of estimates (2–4.5 K) obtained from simulations with state-of-the-art
models of different complexities. 相似文献
998.
V. G. Bondur Yu. V. Grebenyuk K. D. Sabynin 《Izvestiya Atmospheric and Oceanic Physics》2009,45(5):598-607
Based on the results of analyzing the characteristics of currents and temperature measured in the water space of the Mamala
Bay (the Island of Oahu, Hawaii), we investigate the main properties of the field of short-period internal waves, which is
very complex. We focus on analyzing the spectral characteristics and orbit parameters for waves with a period of 20 minutes.
The results of investigations reveal two types of short-period internal waves for this area: intense and fast waves propagating
predominantly toward the ocean and weaker and slower waves propagating mainly toward the coast. Suppositions are made on how
these waves form: the strong and fast waves are likely to be caused by the decay of locally generated internal tides near
the shelf edge, while the weak and slow and very short waves seem to result from the specific interaction between the pycnocline
and strong tidal currents over a steep slope. 相似文献
999.
The proposed concept of the “marine coastal zone” (MCZ) is substantiated with considering the role of the neotectonics in
the formation and evolution of the corresponding morphologic system using the Antarctic Peninsula as an example. For this
purpose, the results of the immediate geologic-geomorphologic observations are correlated with an original schematic neotectonic
map compiled for the region in question. It is shown that neotectonic movements are responsible for the block structure of
the coastal zone representing its most stable element, which is complicated by subsequent regional exogenic coast-forming
processes with the glacial one being dominant. Other aspects of the marine coastal zone influenced by neotectonics are also
considered. A new (near-polar) type of the marine coastal zone is defined. 相似文献
1000.
We analyze the statistical structure of the data of remote sensing of the fields of surface temperature and the concentration
of chlorophyll in the northwest part of the Black Sea with an aim to apply the method of optimal interpolation to the restoration
of the maps of these fields according to the restricted amounts of data. We determine the scales of smoothing for the selection
of the random components of the fields and estimate their difference from the statistical model uniform and isotropic over
the space correlation coefficients. The functions of spectral densities are constructed along various sections and the best
intervals of discretization of the fields required to perform the optimal interpolation with given accuracy are determined.
It is shown that the construction of the maps of fields under the conditions of controlled accuracy of reconstruction of their
values remains possible even if the amounts of the input satellite data are significantly decreased. We consider a procedure
of evaluation of the best possible amounts of data required for the use of the method of optimal interpolation. Some examples
of application of this procedure to the data of remote sensing of the fields of surface temperature and the concentration
of chlorophyll are presented. 相似文献