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231.
Spatially continuous rock assemblages that share similar environmental evolution or structural features can be classified as a single tectonic unit. This approach enables to link dispersed units or massifs with each other and sometimes can be subjective, depending on the classification criteria. The relationship and the nature of the contact between the Strandja Massif and the ?stanbul Zone have been controversial due to the Cainozoic cover. Amalgamation of these units was claimed as early as the Aptian-Albian.

Lower Triassic sedimentary rocks, which are overlain by the Carboniferous flysch with a N-verging thrust fault are exposed NW of the ?stanbul Zone. This study reveals the spatial relationship between the Strandja Massif and the ?stanbul Zone deduced from the U-Pb dating and Lu-Hf isotopes of the detrital zircons from these Lower Triassic clastics. Our results show that the early Triassic basin was fed from a provenance that included arc-related Upper Carboniferous-Lower Permian magmatic rocks which is much more likely to be the Strandja Massif than the ?stanbul Zone. The second outcome of this study is that a unit that previously assigned to Palaeozoic turned out to be Triassic, which brings the Strandja Massif farther to the east, into the northern ?stanbul Zone.  相似文献   
232.
The demand for water by growing populations and agricultural operations in the Antalya urban area is expected to increase significantly in the near future. For that reason, alternative water sources are important to the future of Antalya. There are a large number of water sources around Antalya to meet the water needs of the city. These are classified as surface water, groundwater, and reclaimed water. One of the options considered is the provision of water from rock pores. Rock pore water has been adopted as a potential alternative for water resources in the area. It is proposed to drill horizontal galleries using the microtunnel machine to the rock masses in carbonate aquifers to obtain new water resources. This study presents a useful method to find water supply alternatives for urban areas like Antalya. In this study, karstified rock masses have been evaluated for the karst hydrosystems and water source from rock pores using geographic information systems and analytical hierarchy process. Additionally, this study discusses the practical value of the provision of water from rock pores, as well as the possibility of application and selection of potential areas.  相似文献   
233.
Today, waste is an important environmental problem that needs to be solved. The way it is collected and managed should be considered with respect to the negative impact on the environment. Although the Atabey aggregate quarry was operated with natural sand-gravel until 2 years ago, it was closed due to technological renovation in the crushing-screening unit and uneconomic production. This area was later used by the Atabey Municipality as a waste storage area. Thus, uncontrolled storage occurred at the quarry site. As a result, new, more intensive environmental problems have emerged in the area, such as visual pollution and the pollution of groundwater. This paper evaluates the impact of municipal solid waste disposal in an abandoned quarry site on groundwater, land surface temperature, land surface moisture, and vegetation cover using GIS (Geographic Information Systems) and remote sensing technologies. According to the obtained results, the solid wastes stored in the area caused groundwater pollution, increased surface temperature, and reduced soil moisture.  相似文献   
234.
Geotechnical and Geological Engineering - Kizilkaya ignimbrite, characterized by a blocky structure in the Ihlara Valley (Cappadocia, Turkey), poses many hazards to visitors and the human-made...  相似文献   
235.
The North Atlantic Oscillation (NAO) is a large‐scale mode of natural climate variability governing the path of Atlantic mid‐latitude storm tracks and precipitation regimes in the Atlantic and Mediterranean sectors. The primary focus of this study is to investigate the variability of lake levels in seven lakes scattered across Turkey using the method of continuous wavelet transforms and global spectra. The long winter (December, January, February and March) lake‐level series and the NAO index (NAOI) series were subjected to wavelet transform. The global wavelet spectrum (energy spectrum of periodicities) of lake levels and winter NAOI anomalies, in most cases, revealed a significant correlation. It was shown that the Tuz, Sapanca, and Uluabat lakes reflect much stronger influences of the NAO than the other four lakes. In contrast, weak correlations were found in the coastal areas of the Mediterranean and eastern Turkey. The periodic structures of Turkish lake levels in relation to the NAO revealed a spectrum between the 1‐year and 10‐year scale level. Although the periodicities of more than 10‐year scale levels were detected, explaining significant relations between the NAO and these long‐term periodicities remains a challenging task. The results of this study are consistent with the earlier studies concerning the teleconnection between the NAO and climate variables in Turkey. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
236.
A study was conducted to investigate the trace metal pollution of water and sediments of downstream of Tsurumi River, Yokohama, Japan. Twenty samples of water and sediments were collected from the river starting from Tokyo bay side up to the junction point of the Yagami River. Results show that the mean concentrations of chromium, cupper and nickel in water greatly exceed (>100 times) the surface water standard. The concentration of molybdenum and lead was also higher than standard values while iron and manganese was lower than that of surface water standard. The mean concentration of zinc, cupper, cadmium, lead, chromium, vanadium, bromine and iodine was 381.1, 133.0, 1.0, 40.8, 102.9, 162.0, 71.5 and 10.6 μg/g sediments, respectively and was greatly exceed the average worldwide shale concentrations and average Japanese river sediment values. However, mean concentration of arsenic, nickel and strontium was 11.0, 36.6 and 164.6 μg/g sediments, respectively which was lower than the average shale value. Other analyzed trace metals, including barium, zirconium, rubidium, yttrium, tin, antimony, cesium, lanthanum, cerium, praseodymium and neodymium were detected in river sediments; the concentration of which was close to the Japan’s river sediment average values. Pollution load index values of the sites of the studied area ranged from 1.24 to 7.65 which testify that the river sediments are polluted. The PLI value of the area was, however, high (6.53) as the concentration of trace metals like zinc, cupper, cadmium, lead and chromium were very high and were the major pollutants.  相似文献   
237.
In this study, 30 topsoil samples were collected from Karaduvar area (Mersin, SE Turkey) where at present various industrial and agricultural activities are occurring. Using a five-step ultrasound-assisted sequential extraction (UASE) procedure, trace elements in soil samples were partitioned into the following: (1) soluble-exchangeable; (2) bound to carbonates; (3) bound to Fe- and Mn-oxides; (4) bound to organic matter and sulfide compounds, and (5) residual fraction. Concentrations of 11 trace elements in the extracts were determined using ICP-MS. Total concentrations ranged between (in mg kg−1) 3.35 and 7.26 for As; 1.18 and 3.96 for Cd; 10.76 and 20.26 for Co; 37.99 and 63.48 for Cr; 18.55 and 243.1 for Cu; 338.7 and 565.6 for Mn; 4.42 and 6.44 for Mo; 148 and 279.3 for Ni; 10.12 and 73.71 for Pb; 17.93 and 36.55 for V, and 25.46 and 331.7 for Zn. Factor analysis was applied to dataset in order to discriminate between natural and anthropogenic pollution sources and factors controlling the spatial distribution of trace elements in the area. Results suggest that distributions of Co, Cr, Mn, and Ni are mainly controlled by lithological factors, whereas, distributions of Cu, Pb, and Zn can be attributed to agricultural activities such as pesticide/herbicide use and fertilizer application, as well as irrigation with petroleum hydrocarbon-contaminated groundwater. Highest concentrations of Cd and Mo are generally observed around the diesel-fired thermal power plant and ATAŞ refinery. Highest concentrations of As and V are generally observed at the NW sector of the area; however, no definitive source can be designated for both of these elements.  相似文献   
238.
Analytical solutions are obtained for gravitational and magnetic fields at given distributions of area matter density and surface currents.Numerical solutions ae obtained for a magnetized non-rotating disk, the equilibrium of which is governed by the balance of magnetic and gravitational forces. The models are shown to be unsable against short-wave perturbations. Pressure can make a small contribution (of the order of a few percent) towards stabilizng the disk against short-wave perturbations. Such disks may appear in some galactic nuclei.  相似文献   
239.
A computational method, based on an advanced elasto-plastic large strain formulation, well suited for the analysis of the cone penetration problem, is presented. A new approach of finite strain elasto-plastic analysis is employed.13 The basic (non-rate) constitutive relations are developed in a spatial reference space to preserve their physical significance. They are subsequently transformed in Lagrangian co-ordinates, and through simple time differentiation, their rate equations are introduced. The method is computationally implemented with the finite element method and special provisions are taken to allow for the moving boundary conditions of the problem.  相似文献   
240.
一幢钢筋混凝土建筑结构的强地震反应观测   总被引:3,自引:2,他引:3  
介绍了美国加州强震观测计划(CSMIP)中一幢建筑结构地震反应台阵的观测方案,描述了被观测结构的有关情况,给出了该台阵于1994年美国北岭地震中获得的结构地震反应的观测资料。  相似文献   
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