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241.
Mineralogy and Petrology - In the Gotsu area of the c. 200 Ma high-P/T Suo metamorphic belt in the Inner Zone of southwest Japan, blueschists occur as lenses or layers within pelitic... 相似文献
242.
A new isolation interface is proposed in this study to retrofit existing buildings with inadequate soft stories as well as new structures to be constructed with soft first story intended for architectural or functional purposes. The seismic interface is an assembly of bearings set in parallel on the top of the first story columns: the multiple‐slider bearings and rubber bearings. The multiple‐slider bearing is a simple sliding device consisting of one horizontal and two inclined plane sliding surfaces based on polytetrafluoroethylene and highly polished stainless steel interface at both ends set in series. A numerical example of a five‐story reinforced concrete shear frame with soft first story is considered and analyzed to demonstrate the efficiency of the proposed isolation system in reducing the ductility demand and damage in the structure while maintaining the superstructure above the bearings to behave nearly in the elastic range with controlled bearing displacement. Comparative study with the conventional system as well as various isolation systems such as rubber bearing interface and resilient sliding isolation is carried out. Moreover, an optimum design procedure for the multiple‐slider bearing is proposed through the trade‐off between the maximum bearing displacement and the first story ductility demand ratio. The results of extensive numerical analysis verify the effectiveness of the multiple‐slider bearing in minimizing the damage from earthquake and protecting the soft first story from excessively large ductility demand. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
243.
The Inference of Geo-Mechanical Properties of Soft Rocks and their Degradation from Needle Penetration Tests 总被引:2,自引:1,他引:1
Needle penetration tests (NPTs) are used for inferring the uniaxial compressive strength of soft rocks, particularly in tunneling through squeezing rocks and foundations on weathered rocks in Japan. The device measures the applied load and the penetration depth of its needle. The ratio of applied load to penetration depth was originally called the needle penetration index (NPI). In this study, this device has been used to infer the geo-mechanical properties of soft rocks from Japan, Turkey, Indonesia, and Egypt. Various equations are presented to infer the geo-mechanical properties in terms of the NPI and compared with the experimental results. The possibility of evaluating the anisotropy of geo-mechanical properties is shown. Furthermore, the characterization of geo-mechanical properties of fault/fracture and slip (shear) surfaces is explained. Some additional equations are given to consider the degradation of geo-mechanical properties as a function of water content, weathering state, and number of cycles of freezing–thawing. Furthermore, the possibility of evaluating the time-dependency characteristics of soft rocks by needle penetration testing is discussed through experiments. It is shown that the effects of water content, weathering state, and number of cycles of freezing–thawing and time-dependency can be evaluated using the NPT technique. 相似文献
244.
245.
We describe a catalogue of solar flares observed by the three instruments (SOT, XRT, EIS) onboard the Hinode satellite. From the launch of the Hinode satellite in September 2006 until late 2011, about 5000 solar flares (larger than A-class in the GOES classification) occurred during the five-year period of Hinode observations, and more than half of them were captured by the Hinode telescopes. Observation information for RHESSI and Nobeyama Radioheliograph are also included in the catalogue. This catalogue is distributed to users through the Internet. It will be useful and helpful for scientists in surveying flares to be analyzed, facilitate access to Hinode data, and help advance data analysis activities among the world solar community. 相似文献
246.
An application of a pin‐supported wall‐frame system in retrofitting an eleven‐story steel reinforced concrete frame is introduced. The retrofit aims at enhancing integrity and avoiding weak story failure in an existing moment‐resisting frame. Seismic performance of the building before and after the retrofit is assessed through nonlinear dynamic analysis. The results show that the pin‐supported walls are effective in controlling the deformation pattern of the ductile frame and hence in avoiding weak story failure. With the well‐controlled deformation pattern, carefully arranged energy dissipating devices are able to concentrate energy dissipations so that damage to the rest of the structure can be significantly reduced. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
247.
Based on almost all available published age data, the protolith ages, peak metamorphic ages and cooling rate of the Sambagawa metamorphic belt have been discussed and the latest constraints on the ages of the Sambagawa metamorphism and subduction-related accretionary evolutions were summarized. Peak metamorphic conditions attained within the Kuma nappe complex at ca. 145~185 Ma, and uplift through ca. 500℃ at ca. 150 Ma and 350~400℃ at ca. 110~ 115 Ma. The protolith sediments of the Besshi nappe complex were accumulated and subsequently progressively subducted and suffered high P-T prograde metamorphism during the Kuma nappe complex uplifting. The Besshi nappe complex arrived maximum metamorphic conditions at ca. 110 ~ 120 Ma and subsequently started rapid uplift with the cooling rate of ca. 14.2℃/Ma at ca. 75 ~85 Ma, followed with the cooling rate of ca. 6.0 ~8.9℃/Ma. The Oboke nappe complex started subduction later than other tectonic units and arrived the peak metamorphic conditions at ca. 75 Ma, which followed by the uplift with a cooling rate of ca. 8℃/Ma. 相似文献
248.
Multispectral satellite remote sensing can predict shallow-water depth distribution inexpensively and exhaustively, but it requires many in situ measurements for calibration. To extend its feasibility, we improved a recently developed technique, for the first time, to obtain a generalized predictor of depth. We used six WorldView-2 images and obtained a predictor that yielded a 0.648 m root-mean-square error against a dataset with a 5.544 m standard deviation of depth. The predictor can be used with as few as two pixels with known depth per image, or with no depth data, if only relative depth is needed. 相似文献
249.
Osamu Nagafuchi Neil L. Rose Akira Hoshika Kenichi Satake 《Journal of Paleolimnology》2009,42(3):359-371
Fly-ash particles comprising spheroidal carbonaceous particles (SCP) and inorganic ash spheres (IAS), produced from industrial
fossil-fuel combustion, are found in lake sediments throughout the world where they provide an historical record of atmospheric
pollutant deposition. These particles have been widely used to assess the temporal and spatial distribution of industrial
atmospheric pollution in both freshwater and terrestrial environments in Europe and the USA. However, there have been very
few palaeolimnological fly-ash studies undertaken in Japan and none in Japanese mountain lakes. Here, we present the historical
SCP and IAS records from a radiometrically dated sediment core taken from Lake Akagi-konuma (36°31′ 54″N, 139°11′ 32″E; elevation
1,470 m) located 100 km north-west of Tokyo. Meteorological data and back trajectory analyses confirm potential sources both
within Japan and further afield in China and South Korea. SCP contamination began in the 1950s and increased rapidly to a
peak in the mid-1980s. It is thought this represents contamination of Japanese origin, principally oil-fired power stations
within 150 km of the lake. The profile of IAS, almost solely coal-derived, shows a rapid increase in the 1970s, in contrast
to the record of coal consumption in Japan. The IAS record is therefore thought to reflect long-range transport from coal
combustion sources in eastern China which started to expand in the 1970s. This raises concerns over the potential impact on
Japanese mountain areas from recent rapid increases in, and predicted acceleration of, emissions from this industrial process.
The scale of SCP contamination recorded in Lake Akagi-konuma is equivalent to moderately impacted mountain lakes in Europe,
but is at the upper end of the range for remote lakes in the western United States. 相似文献
250.
Naoki Kabeya Nick A. Chappell Wlodek Tych Akira Shimizu Shiho Asano Hiroaki Hagino 《水文科学杂志》2016,61(9):1716-1727
ABSTRACTA new method known as Unobserved Components–Dynamic Harmonic Regression (UC-DHR) was applied to a 39-year record of rainfall and streamflow for three sub-catchments of the Sarukawa Experimental Watershed in southwestern Japan. Some 25% of the timber was harvested from one of the sub-catchments in May–July 1982 and the objective was to quantify the magnitude of this effect relative to the effects of climate cycles (e.g. Southern Oscillation Index). The observed effects of inter-annual climate cycles (i.e. 0.89–1.36 mm/d) were seen to be comparable (i.e. 0.70–1.17 mm/d) to the effects of harvesting 25% of the standing timber. This result underlines the importance of always quantifying the effect of climate on streamflow response when harvesting impacts are studied.
Editor D. Koutsoyiannis; Associate editor T. Okruszko 相似文献