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排序方式: 共有188条查询结果,搜索用时 15 毫秒
181.
This paper first traces the major changes in the relationship between the (Orthodox) Church and State in the different Russian polities, using Madeley’s framework of historic mono-confessional blocs and multi-confessional belts. Second, it outlines the recent tendencies and characteristic features of church–state relations in today’s Russia. Third, using data from sociological surveys, it analyses the current dominant popular perceptions and societal attitudes towards religion and the State, including religious freedom. Being part of the historic mono-confessional Orthodox bloc, the different Russian polities produced different models of church–state relations: from a symphony of religious and political powers, through a forced nationalization of the Orthodox Church (Russian Empire from the époque of Peter the Great until revolution of 1917), and forced secularisation (during the Soviet Union), to a return of mutual support of (Orthodox) Church and State despite a formal (constitutional) separation in Putin’s Russia.  相似文献   
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183.
Journal of Paleolimnology - Analysis of Cladocera (Crustacea: Branchiopoda) subfossil remains in lake sediments features prominently in paleolimnological studies. It is well known, however, that...  相似文献   
184.
We address issues associated with non-local magnetic boundary conditions for non-spectral dynamo simulations. We introduce an integro-differential formulation for a domain bounded by an insulating outer domain. We show how to combine the flexibility of a local discretisation with a rigorous formulation of magnetic boundary conditions in arbitrary geometries. This formulation substantiates from mathematical point of view a new method for numerical solution of magnetohydrodynamic problems with non-local boundary conditions based on coupling finite volumes and boundary elements. Finally, we discuss practical efficiency of this new method.  相似文献   
185.
This project has reconstructed the palaeogeographic and environmental evolution of Lake Chokrak on the Kerch Peninsula, Ukraine, during the mid‐ and late‐Holocene. This record has been evaluated in association with a regional archaeological data set to explore human–environment interactions over this period. The results show major changes in the palaeogeographic setting of Lake Chokrak since the 3rd millennium B.C., when the postglacial marine transgression had started to fill the study area. Microfaunal analyses reveal the long persistence of an open marine embayment that only became separated from the Sea of Azov when a sand barrier developed during the late 2nd millennium B.C. When colonizing the Black Sea region after the 8th century B.C., the Greek settlers erected a fortification with a small settlement on a promontory that was by then a peninsula‐like headland extending into the lake. The colonists abandoned their settlement at the end of the 1st millennium B.C. when the depth of the surrounding lake decreased from 1.5 m to less than 1 m. Today, Lake Chokrak dries up completely during summer. A detailed relative sea level (RSL) curve for the northern coast of Kerch has been established. Sea level reached its highest position at the present day. Since the 3rd millennium B.C., sea level continuously rose, without any of the previously postulated regression/transgression cycles. The RSL curve indicates differential subsidence rates within short distances in relatively stable areas, exceeding 40 cm per 1000 years. © 2012 Wiley Periodicals, Inc.  相似文献   
186.
First-ever ice core drilling at Mt. Kazbek (Caucasus Mountains) took place in the summer of 2014. A shallow ice core (18 m) was extracted from a plateau at ~4500 m a.s.l. in the vicinity of the Mt. Kazbek summit (5033 m a.s.l.). A detailed radar survey showed that the maximum ice thickness at this location is ~250 m. Borehole temperature of ?7 °C was measured at 10 m depth. The ice core was analyzed for oxygen and deuterium isotopes and dust concentration. From the observed seasonal cycle, it was determined that the ice core covers the time interval of 2009–2014, with a mean annual snow accumulation rate of 1800 mm w. eq. Multiple melt layers have been detected. δ18O values vary from ?25 to ?5‰. The dust content was determined using a particle sizing and counting analyzer. The dust layers were investigated using scanning electron microscopy and X-ray diffraction analysis. Dust can be separated into two categories by its origin: local and distant. Samples reflecting predominantly local origin consisted mainly of magmatic rocks, while clay minerals were a characteristic of dust carried over large distances, from the deserts of the Middle East and Sahara. The calculated average dust flux over three years at Kazbek was of 1.3 mg/cm2 a?1. Neither δ18O nor dust records appear to have been affected by summer melting. Overall, the conditions on Kazbek plateau and the available data suggest that the area offers good prospects of future deep drilling in order to obtain a unique environmental record.  相似文献   
187.
The Grad–Shafranov reconstruction is a method of estimating the orientation (invariant axis) and cross section of magnetic flux ropes using the data from a single spacecraft. It can be applied to various magnetic structures such as magnetic clouds (MCs) and flux ropes embedded in the magnetopause and in the solar wind. We develop a number of improvements of this technique and show some examples of the reconstruction procedure of interplanetary coronal mass ejections (ICMEs) observed at 1 AU by the STEREO, Wind, and ACE spacecraft during the minimum following Solar Cycle 23. The analysis is conducted not only for ideal localized ICME events but also for non-trivial cases of magnetic clouds in fast solar wind. The Grad–Shafranov reconstruction gives reasonable results for the sample events, although it possesses certain limitations, which need to be taken into account during the interpretation of the model results.  相似文献   
188.
The geological structure, age, and genesis of sedimentary—volcanogenic, metamorphic, and metasomatic rocks from the Terskii greenstone belt fringing the southern Imandra—Varzuga structure in the southeastern Kola Peninsula are discussed with defining main stages in endogenic activity of the region in the Late Archean and Early Proterozoic. The U-Pb method (SHRIMP-II, ID-TIMS, and Pb-LS techniques) was used to determine the age of volcano-sedimentary rocks of the Imandra Group as well as that of magmatic and superimposed metamorphic and metasomatic processes. The basic—intermediate metavolcanics of the Imandra Group are dated at 2.67 Ga, which corresponds to the Lopingian Gimol’skii Superhorizon (Late Archean). The Archean metavolcanics were subjected to Early Proterozoic regional metamorphism 2.1 Ga ago and metasomatic processes in the period of 1.85 to 1.77 Ga ago. The obtained data indicate multistage evolution of rock formation in the Terskii greenstone belt located in the southern flank of the Imandra—Varzuga structure in the Kola Peninsula.  相似文献   
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