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61.
Osman M. Kamel 《Earth, Moon, and Planets》1992,58(1):97-103
Motivated by the recent proposals of A. Abian, we investigate in this paper the second order perturbations up to the second degree in eccentricity-inclination of a new model of our solar system after the landing of Mars or Ceres on the Earth. The theory is established through the HoriLie technique and in terms of Jacobi coordinates and Poincare canonical variables. 相似文献
62.
We expand the planetary Hamiltonian function with its two parts, the principal and the indirect, up to the seventh order in the planetary masses. We adopt the Jacobi-Radau system of origins. The expansiion is valid for any number of planets. 相似文献
63.
We construct a fifth-order with respect to masses Jupiter-Saturn secular theory by Hori-Lie canonical technique. The J-S Hamiltonian includes both parts of the perturbing function. The influence of the 2:5 critical terms is taken into consideration. The Jacobi-Radau system of origins is adopted and the theory is expressed in terms of the Poincaré canonical variables. 相似文献
64.
Osman Sivrikaya 《Environmental Geology》2008,53(7):1585-1595
To prevent the leakage of pollutant liquids into groundwater and sublayers, the compacted fine-grained soils are commonly
utilized as mineral liners or a sealing system constructed under municipal solid waste and other containment hazardous materials.
This study presents the correlation equations of the compaction parameters required for construction of a mineral liner system.
The determination of the characteristic compaction parameters, maximum dry unit weight (γ
dmax) and optimum water content (w
opt) requires considerable time and great effort. In this study, empirical models are described and examined to find which of
the index properties correlate well with the compaction characteristics for estimating γ
dmax and w
opt of fine-grained soils at the standard compactive effort. The compaction data are correlated with different combinations of
gravel content (G), sand content (S), fine-grained content (FC = clay + silt), plasticity index (I
p), liquid limit (w
L) and plastic limit (w
P) by performing multilinear regression (MLR) analyses. The obtained correlations with statistical parameters are presented
and compared with the previous studies. It is found that the maximum dry unit weight and optimum water content have a considerably
good correlation with plastic limit in comparison with liquid limit and plasticity index. 相似文献
65.
Two major earthquakes occurred on October 23rd, 2011 (M=7.1) and November 9th, 2011 (M=5.6) in Tabanli and Edremit districts of Van province in Turkey, respectively. New settlement areas for Van city were determined after these destructive earthquakes. One of the most important areas for new settlements to be built was Edremit region, consisting travertine where nearly 80% of new housing units (12.384) were built by TOKI (Housing Development Administration of Turkey). Travertines have different lithotypes depending on their depositional process such as crystalline crust, shrub, reed which can affect mechanical and engineering properties of travertine and each level has different handicaps. The purpose of this study is to investigate the relationship between lithotype and physico-mechanical properties of travertines. According to the results, lithotype has an effect on physical, mechanical and rock mass properties of travertine. It is ascertained by several research methods that various handicaps may occur on such areas when the active tectonic structure of the area is evaluated along with the karstic cavities within the travertine and different lithotype qualities. 相似文献
66.
Faisal Rehman Helmy Salah Osman Abouelnaga Faisal Rehman 《Arabian Journal of Geosciences》2016,9(4):312
Ground penetrating radar is a noninvasive geophysical technique that can be used to infer subsurface geological, geotechnical, and petrophysical attributes. For water contamination studies, ultimate target, i.e., contaminant flow, is demarcated with the help of dielectric permittivity, water content, and porosity. The dielectric permittivity facilitates to evaluate water content; whereas the dielectric permittivity can be estimated by using the interval velocity, and porosity can be estimated by using the information of water content and dielectric permittivity. All these parameters are interlinked. This paper describes different empirical and mixing relationships to calculate approximately these parameters and their utilization in predicting the hydrogeological model of the area. 相似文献
67.
68.
69.
Osman Demircan 《Astrophysics and Space Science》1986,123(2):305-312
A part of the light curves of two detached (CD Tau and V909 Cyg) and one semi-detached (Algol) binaries have been analysed with the emphasis on the determinacy of the parameters of different systems from a part of their eclipse curves. A model light curve for whichr
1=0.050,r
2=0.150,i=90°, andL
1=0.800 were chosen, has also been considered for a further clarification of the determinacy problem of the eclipse parameters. Some insight into the determinacy is gained by varying one parameter and adjusting the others for the best fit to the light curves in the considered eclipse phases. It was realised that the determinacy problem of the unknown parameters is stored in the determinacy of the type of the eclipse minima. The attempts of the solutions with a false choice of initial elements result in finding (i) no minimum of 2 to give any acceptable solution, (ii) rapid departure from the false start and convergence on the correct solution, or (iii) a false solution mostly with a true inclinationi, but wrong sense of the ratio of the radii. 相似文献
70.
In this paper, we demonstrate the effectiveness of steerable filters as a method of delineating the boundaries of subsurface geological structures. Steerable filters, generally used for edge detection on 2-D images, have the properties of band pass filters with certain directions and are applied to many image processing problems. We first tested the method on synthetic data and then applied it to the aeromagnetic data of İskenderun Basin and adjacent areas.İskenderun Basin is located in the Northeastern Mediterranean where African–Arabian and Anatolian plates are actively interacting. The basin fill records a complex tectonic evolution since the Early Miocene, involving ophiolite emplacement, diachronous collision of Eurasian and Arabian plates and subsequent tectonic escape related structures and associated basin formation. Geophysical investigations of the tectonic framework of İskenderun Basin of Turkey provide important insights on the regional tectonics of the Eastern Mediterranean and Middle East. In this study we show geological structures, which are responsible for the magnetic anomalies in İskenderun Basin and enlighten the structural setting of the Northeastern Mediterranean triple junction using steerable filters. We obtained a magnetic anomaly map of the region from the General Directorate of Mineral Research and Exploration as raw data and then evaluated this by steerable filters. We determined the magnetic anomaly boundaries for İskenderun Basin by using various types of steerable filters and correlated these to drilling data and seismic profiles from the Turkish Petroleum Corporation. The result of the steerable filter analysis was a clarified aeromagnetic anomaly map of İskenderun Basin. The tectonic structure of İskenderun Basin is divided into regions by an N–S trending oblique-slip fault defined by the steerable filter outputs. We propose a new tectonic structure model of İskenderun Basin and modify the direction of the East Anatolian Fault Zone. In our model, East Anatolian Fault Zone cross-cuts the basin as a narrow fault zone and continues towards the Cyprus arc. 相似文献