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91.
An integration of GIS and remote sensing in groundwater investigations: A case study in Burdur, Turkey 总被引:13,自引:4,他引:9
The importance of groundwater is growing based on an increasing need and decreasing spring discharges in the Burdur area. Remote Sensing and the Geographic Information System (GIS) have been used for investigation of springs, which are an important groundwater source. The chemical composition of groundwater is not of drinking water quality in Burdur city and water in the Burdur residential area is being obtained from the Cine plain.The purpose of this study was to investigate new water sources by using remote sensing and GIS methods. Geology, lineament and land use maps of the research area were prepared using the Landsat TM satellite image composed of different analyses on the TM 7–4-1 band. In addition, contours, creeks, roads and springs were digitized using a topographic map of 1/100,000 scale to produce a drainage density map. A groundwater potential map was produced which integrated thematic maps, such as annual rainfall, geology, lineament density, land use, topography, slope and drainage density. According to this investigation, the surrounding villages of Askeriye, Bugduz, Gelincik, Taskap and Kayaalt were determined to be important from the point of view of groundwater potential in the research area. 相似文献
92.
Texture and grain size is of great importance in understanding the mechanical properties of rocks. The aim of this study was to investigate textural and slaking durability characteristics, and correlate them with the gypsum types where the dolines occurred, with particular reference to the texture and crystal size. The investigation comprised two stages: field work and laboratory testing. Initially, rock samples were obtained from various representative karstified and non-karstified locations. Thereafter, mineralogical, physical and slaking durability characteristics of the gypsum samples were determined by means of laboratory testing. After the field and laboratory works, the geological, mineralogical and slaking durability characteristics of the study area gypsum were reviewed and discussed from the point of view of doline formation. Results showed that fine grain sized alabastrine gypsum tends to be karstified and leads to doline formation. This is closely related to the crystal size, texture and attributable to the slaking durability of the gypsum. Consequently, the results demonstrate that the texture, especially crystal size, and effective porosity are important parameters controlling the slake durability of the gypsum and doline formation. 相似文献
93.
Experimental investigation of the effect of grading characteristics on the liquefaction resistance of various graded sands 总被引:1,自引:1,他引:0
The liquefaction susceptibility of various graded fine to medium saturated sands are evaluated by stress controlled cyclic triaxial laboratory tests. Cyclic triaxial tests are performed on reconstituted specimens having global relative density of 60%. In all cyclic triaxial tests; loading pattern is selected as a sinusoidal wave form with 1.0 Hz frequency, and effective consolidation pressure is chosen to be 100 kPa. Liquefaction resistance is defined as the required cyclic stress ratio which caused initial liquefaction in 10 cycles during the cyclic triaxial test. The results are used to draw relationship between grading characteristics (e.g. coefficient of uniformity and coefficient of curvature) and the liquefaction resistance of various graded sands. It is found that a relationship between cyclic resistance and any of the size (i.e. D10, D30 or D60) would be more realistic than to build a relation between grading characteristics and the cyclic resistance. 相似文献
94.
Structural and geomorphological aspects of the Kat landslides (Tokat—Turkey) and susceptibility mapping by means of GIS 总被引:3,自引:0,他引:3
Kat County, which is located in a slope of hilly region and constructed in the side of a mountain along the North Anatolian Fault Zone, is frequently subject to landslides. The slides occur during periods of heavy rainfall, and these events cause destruction to property, roads, agricultural lands and buildings. In the last few decades, a lot of houses and buildings have been damaged and destroyed. Settlement areas have remained evacuated for a long time. The slope instabilities in the study area are a complex landslide extending from north to south containing a lot of landslides. Field investigations, interpretation of aerial photography, analyses of geological data and laboratory tests suggest that some factors have acted together on the slopes to cause the sliding. In the wet season, the slopes became saturated. As the saturation of the earth material on the slope causesa rise in water pressure, the shear strength (resisting forces) decreases and the weight (driving forces) increases; thus, the net effect was to lower the safety factor. Previous failures have affected the rock mass, leading to the presence of already sheared surfaces at residual strengths. The relation between the joint planes and the instability of the slope in the study area was discussed and it was found that the potential slope instabilities are mainly in the directions of NW–SE, NE–SW and N–S. The landslide susceptibility map obtained by using the geographical information system showed that a large area is susceptible and prone to landslides in the northern part of the study area.An erratum to this article can be found at 相似文献
95.
Soil liquefaction susceptibility and hazard mapping in the residential area of Kütahya (Turkey) 总被引:2,自引:0,他引:2
This study presents the results of both field and laboratory tests that have been undertaken to assess liquefaction susceptibilities
of the soils in Kütahya city, located in the well-known seismically active fault zone. Liquefaction potentials of the sub-surface
materials at Kütahya city were estimated by using the geological aspect and geotechnical methods such as SPT method of field
testing. And, the data obtained have been mapped according to susceptibility and hazard. The susceptibility map indicated
“liquefable” and “marginally liquefable” areas in alluvium, and “non-liquefable” areas in Neogene unit for the magnitude of
earthquake of M=6.5; whereas, liquefaction hazard map produced by using of liquefaction potential index showed the severity categories from
“very low” to “high.” However, a large area in the study area is prone to liquefy according to liquefaction susceptibility
map; the large parts of the liquefable horizon are mapped as “low” class of severity by the use of the liquefaction potential
index. It can be said that hazard mapping of liquefaction for a given site is crucial than producing liquefaction susceptibility
map for estimating the severity. Both the susceptibility and hazard maps should be produced and correlated with each other
for planning in an engineering point of view. 相似文献
96.
Muhammet Yilmaz 《水文科学杂志》2019,64(7):820-834
A comprehensive evaluation of trends in annual instantaneous maximum flows (AIMF) from 153 gauge stations located in 26 river basins in Turkey is presented. Two traditional non-parametric trend tests, the Mann-Kendall (MK) and Spearman’s rho (SR), are used to quantify the significance of trends, while Sen’s slope method is applied to determine the magnitude of trends. The traditional tests indicate that the AIMF records of 57 stations showed statistically decreasing trends, while those of six stations showed an increasing trend. Sen’s trend method, which provides more detailed assessment of the trends in different clusters (low, medium and high), was applied to the AIMF series and the results were compared with traditional tests. Sen’s trend method indicated that all flow clusters at nine stations have increasing or decreasing trends, although no significant trend was detected by the MK and SR tests. 相似文献
97.
Nomqhele Z. Nkosi Musa S. D. Manzi Gillian R. Drennan Halil Yilmaz 《Studia Geophysica et Geodaetica》2017,61(1):115-144
Physical property measurements were integrated with mineralogical analyses to better understand the nature of the seismic reflectivity of the deepest (>3.5 km depth) gold ore body (Carbon Leader Reef). The CLR lies at depths between 3.5 km and 4.5 km below the surface. Over 50 drill-core samples were selected for geochemical analyses, density and seismic velocity measurements. Ultrasonic measurements were conducted at ambient and elevated stresses, using transducers operating at 0.5 MHz. The study reveals that P-wave velocities generally increase with increasing bulk density. The CLR conglomerate, the gold-bearing reef, has slightly higher P-wave velocity (~5070–5468 m/s) and density values (~2.78 g/cm3) amongst the quartzitic units, possibly due to its massive pyrite content. The quartzite hangingwall and footwall rocks to the CLR exhibit similar P-wave velocity (~5028–5480 and ~4777–5211 m/s, respectively) and density values (~2.68 and 2.66 g/cm3, respectively). The reflection coefficients calculated at the interface between the CLR conglomerate and its hangingwall and footwall units range between ~0.02 and 0.05 which is below the required minimum reflection coefficient value of 0.06 to produce a strong reflection between two lithological boundaries. This suggests that seismic reflection methods might not be able to directly image the CLR, as observed from its poor reflectivity in the 3D seismic data. Samples were also subjected to stresses of up to 65 MPa to simulate in situ-like conditions and to investigate the dependence of seismic velocities on applied stresses. P-wave velocities increase with progressive loading, but at different rates in shale and quartzite rocks as a result of the presence of micro-defects. 相似文献
98.
This paper proposes a simple conceptual mathematical model for the mechanical components of the NEES‐UCSD large high‐performance outdoor shaking table and focuses on the identification of the parameters of the model by using an extensive set of experimental data. An identification approach based on the measured hysteresis response is used to determine the fundamental model parameters including the effective horizontal mass, effective horizontal stiffness of the table, and the coefficients of the classical Coulomb friction and viscous damping elements representing the various dissipative forces in the system. The effectiveness of the proposed conceptual model is verified through a comparison of analytical predictions with experimental results for various tests conducted on the system. The resulting mathematical model will be used in future studies to model the mechanical components of the shake table in a comprehensive physics‐based model of the entire mechanical, hydraulic, and electronic system. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
99.
The present study reports the synthesis of a novel ionophore, calix[4]azacrown ( 5 ) bearing two amino groups at the lower rim along with its oligomeric analogue ( 6 ). The liquid‐liquid extraction properties of these compounds towards selected metal cations and dichromate anions have been evaluated. It is observed that ( 5 ) and ( 6 ) are good extractants for the selected metal cations. However, in the case of dichromate anion, only species ( 5 ) shows remarkable extraction properties at low pH, whereas species ( 6 ) shows poor extraction behavior. The results have importance especially in wastewater treatment to obtain environmentally safe industrial effluent and they should also assist supramolecular chemists in designing and synthesizing more sophisticated host molecules for the removal of toxic pollutants. 相似文献
100.