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The dissipation test evaluation method presented here employs: (i) a point-symmetric, linear, coupled consolidation model with a new boundary condition and a new time factor, (ii) an automatic and mathematically precise, non-linear, inverse problem solver which includes some reliability testing methods and a kind of regularization technique, and (iii) a method to identify the initial condition.The evaluation method is equally applicable to pore water pressure data displaying monotonic or non-monotonic time variation, with the only difference that the initial condition is identified differently during the inverse problem solution.The necessary testing time is very short provided that the pore water pressure is measured well above the tip. This is attributed to the ability of the one-dimensional, linear consolidation model to account for the geometry and the unloading effects that occur when steady penetration of the static cone penetrometer ceases. 相似文献
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Emő Márton Dario Zampieri Paolo Grandesso Vlasta Ćosović Alan Moro 《Tectonophysics》2010,480(1-4):57-72
The central-western and the eastern Southern Alps are separated by the triangular shaped Adige embayment, which belongs to stable Adria and was the site of pelagic sedimentation from the Tithonian through Maastrichtian. The first part of this study presents paleomagnetic results from the Tithonian–Cenomanian Biancone and Turonian–Maastrichtian Scaglia Rossa formations sampled at 33 geographically distributed and biostratigraphically dated localities.The new and high quality paleomagnetic results from the Adige embayment are then combined with coeval paleomagnetic directions from autochthonous Istria (Márton et al., 2008), which also belongs to stable Adria. The combined data set (which for the Late Albian–Maastrichtian time period is constructed similarly to the synthetic African curve by Besse and Courtillot, 2002, 2003) reveals an important tectonic event (Late Aptian–Early Albian) characterized by 20° CCW rotation and sedimentary hiatus.Comparison between paleomagnetic declinations/inclinations expected in an African framework (i.e. with the assumption that Adria is still an African promontory) leads to the following conclusions. The time-distributed Tithonian and Berriasian (150–135 Ma) paleomagnetic directions exhibit the “African hairpin” with an inclination minimum and a sudden change from CW to CCW rotation at 145 Ma. Concerning the younger ages, the declinations for Adria continue to follow the African trend of CCW rotation till the end of Cretaceous. However, the Tithonian–Maastrichtian declination curve for stable Adria is displaced by 10° from the “African” curve as a result of two rotations. The first, an about 20° CW rotation of Adria with respect to Africa took place between the Maastrichtian and the mid-Eocene. During this time the orientation of Adria remained the same, while Africa continued its CCW rotation. The younger rotation (30°CCW) changed the orientation of Adria relative to Africa as well as to the present North. 相似文献
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Júlia Dégi Rainer Abart Kálmán Török Enikő Bali Richard Wirth Dieter Rhede 《Contributions to Mineralogy and Petrology》2010,159(3):293-314
The complex microstructure of kelyphitic rims around garnet in lower crustal garnet granulite xenoliths from the Bakony–Balaton
Highland Volcanic Field, Central Pannonian Basin has been studied in order to identify controls on garnet breakdown. Symplectites
comprised of a vermicular intergrowth of submicron sized anorthite, orthopyroxene and spinel replace garnet at a sharp reaction
front. Based on element distribution maps the transformation of garnet to symplectite is isochemical. Phase diagram calculations
indicate that this reaction was induced by a pressure decrease and/or a temperature increase. In site-specific TEM foils prepared
by focused ion beam technique and oriented parallel and perpendicular to the reaction front 200 nm wide rods of anorthite
and 20 nm wide rods of spinel are identified. The rods are oriented approximately perpendicular to the replacement front and
are embedded in an orthopyroxene matrix. The regular spacing of the symplectite phases along the reaction front suggests that
their growth is controlled by diffusion. The kinetics of symplectite formation has been modelled based on irreversible thermodynamics.
During interaction of the xenolith with the host basalt the microstructure and chemistry of the An–Opx–Spl symplectite was
significantly modified and it was partially replaced by an olivine bearing symplectite. In contrast to primary symplectite
formation, these processes were metasomatic in nature including addition of sodium, titanium and some trace elements from
the basaltic melt and can clearly be discerned from the garnet breakdown. Based on these observations it is inferred that
symplectite formation took place within the deep crust during the extension of the Pannonian Basin between 15 and 30 km depth
at high temperature (850–1,050°C) prior to the volcanic transport to the surface. 相似文献
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Groundwater vulnerability assessment of the SW Trans-Danubian Central Range, Hungary 总被引:3,自引:1,他引:2
The most important karst water reservoir of Hungary is found in the SW Trans-Danubian Central Range, selected as test area
for the proposed "system approach" and the application of GIS/ARC-INFO to vulnerability mapping. In addition, a case-study
exemplifies the particularities of regional karst-aquifer vulnerability, and moreover the interpretation of data and maps
from the very same point of view. The work has resulted in plotting an atlas to be a useful tool in the hands of land-users
and waste-disposal managers, helping them to prevent groundwater deterioration.
Received: 22 July 1996 · Accepted: 12 September 1997 相似文献