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211.
The impact assessment of molasses‐based distillery‐effluent irrigation on groundwater quality around village Gajraula in the district of Jyotiba Phule Nagar, Uttar Pradesh, India was studied by sampling groundwater on monthly intervals consecutively for summer, winter and monsoon seasons during 2006–2007 and water quality parameters, viz. pH, electrical conductivity (EC), chloride (Cl?), sulphate (SO), nitrate (NO), chemical oxygen demand (COD), total solids (TS), total dissolved solids (TDS), sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), zinc (Zn2+), iron (Fe3+), and total coliforms (TC) were monitored. Results depicted that the values of all parameters decreased with increasing depth of water table. Sulphate, nitrate and potassium contents were maximal in agricultural site during monsoon while EC, Cl?, TS, TDS, Na+, Ca2+, Mg2+, Zn, and Fe were maximal in industrial sites during summer. Groundwater samples of residential site harboured maximum coliforms especially during monsoon, highlighting threat to groundwater. Significant positive correlation matrix between coliforms with nitrate, sulphate and potassium ions explained their survival on these nutrients. To overcome this, important measures emphasizing improvement in effluent treatment technology matching site‐specific characteristics are recommended for eco‐friendly ferti‐irrigation. 相似文献
212.
Algorithms for GPS operation indoors and downtown 总被引:6,自引:0,他引:6
Nainesh Agarwal Julien Basch Paul Beckmann Piyush Bharti Scott Bloebaum Stefano Casadei Andrew Chou Per Enge Wungkum Fong Neesha Hathi Wallace Mann Anant Sahai Jesse Stone John Tsitsiklis Benjamin Van Roy 《GPS Solutions》2002,6(3):149-160
The proliferation of mobile devices and the emergence of wireless location-based services has generated consumer demand for
availability of GPS in urban and indoor environments. This demand calls for enhanced GPS algorithms that accommodate high
degrees of signal attenuation and multipath effects unique to the "urban channel." This paper overviews the market for location-based
services and discusses algorithmic innovations that address challenges posed by urban environments.
Electronic Publication 相似文献
213.
If the solar dynamo operates at the bottom of the convection zone, then the magnetic flux created there has to rise to the surface. When the convection zone is regarded as passive, the rising flux is deflected by the Coriolis force to emerge at rather high latitudes, poleward of typical sunspot zones (Choudhuri and Gilman, 1987; Choudhuri, 1989). Choudhuri and D'Silva (1990) included the effects of convective turbulence on the rising flux through (a) giant cell drag and (b) momentum exchange by small-scale turbulence. The momentum exchange mechanism could enable flux tubes of radii not more than a few hundred km to emerge radially at low latitudes, but the giant cell drag mechanism required unrealistically small flux tube radii (a few meters for a reasonable giant cell upflow) to counteract the Coriolis force. We now include the additional effect of Kelvin-Helmholtz instability in a symmetrical flux ring caused by the azimuthal flow induced during its rise. The azimuthal flow crosses the threshold for the instability only if there is a giant cell upflow to drag the flux tubes appreciably. In the absence of such a drag, as in the case of a passive convection zone or in the case of momentum exchange by small-scale turbulence, the azimuthal velocity never becomes large enough to cause the instability, leaving the results of the previous calculations unaltered. The giant cell drag, aided by Kelvin-Helmholtz instability, however, becomes now a viable mechanism for curbing the Coriolis force - 104 G flux tubes with radii of a few hundred km being dragged radially by upflows of 70 m s-1. 相似文献
214.
The paper presents a study of large scale travelling ionospheric disturbances detected by riometers operating at 30 MHz, over São José dos Campos (23°S, 45°W) and a nearby location in Sao Paulo, Brasil. The TID's are observed mainly at night and have wavelengths greater than 500 Km. In a few cases it is possible to determine the E-W component of the velocity of propagation, which is of the order of 450 Km per hour. Most of the events are characterized by disperions; the period is found to increase from half an hour to nearly two hours. These and other features are identified with the propagation of atmospheric gravity waves in the F-region, whose source might be located far away from the observing site. The results also suggest that a suitably designed riometer system could profitably be used for future investigation of gravity waves in the F-region in low latitude. 相似文献
215.
The Banded Hematite Jasper (BHJ) Formation of Noamundi region in Bihar, belonging to the lower part of the Iron Ore Group of early Precambrian age (c. 2900–3200 Ma), exhibits numerous primary depositional and diagenetic features, both in BHJ as well as the associated iron ore deposits. Observed primary depositional features include banding and bedding of different geometric-types, surface-markings including interference ripple-marks, current crescents, linear markings, scour-and-fill structures, etc. and within-mass microstructures such as spherulites, granules, discs and maculose cylindrical bodies. Diagenetic features, such as fabric changes, micro-dessication structures, gravity-density features, etc. and motion-and-disruption features of various kinds are also seen. The significance of various features in terms of probable mode and environments of deposition of BHJ and the iron ore beds has been considered. In general, shallow water environment of deposition in a region proximal to the shoreline with a rather steep paleoslope of the shelf has been surmised. 相似文献
216.
Permian komatiites and associated basalts from the marine sediments of Chhongtash Formation, southeast Karakoram, Ladakh, India 总被引:1,自引:0,他引:1
Summary The Karakoram micro-plate is the southern most sector of the Central Asian micro-plate mosaic which was separated by a narrow
rift basin. A major rifting phase started during Permian time, which lead to drift of not only Karakoram but of the entire
Eurasian (Asian) Plate from Gondwana land. This was at a time when a prominent sequence of black argillites occupied most
part of the Karakoram Tethys basin. The geodynamic setting for this sequence may be interpreted as the evolution of a passive
margin affected by extensional tectonics. The extensional activity is evident from the extrusion of basalts and komatiitic
rocks in the region.
In this paper the geochemical relations between komatiites and basalts of the Chhongtash, southeast Karakoram are investigated.
The basaltic and komatiitic (ultrabasic) flows are petrologically and geochemically distinct, yet they display a close spatial
and temporal association, and they are related to each other through olivine and clinopyroxene fractionation. The chemical
characteristics of the ultrabasic to basic magmatism in the region is consistent with formation above a mantle plume that
impinged on the continental lithosphere. Hence, a model of partial melting in a mantle plume and fractional crystallization
in a deep-seated magma chamber is envisaged to explain the evolution of these volcanic rocks. The komatiite melts are interpreted
to have been derived by high degree partial melting of mantle plumes in the tail region, while the basalts were interpreted
to be the result of interaction of source plume with cool mantle through which the plume head passed. This study is the first
of its kind, to suggest a rift related nature in the Chhongtash, southeast Karakoram, that represent the initial stage of
Mesozoic rifting along the southern margin of Eurasia when Gondwana started to drift away from Eurasia. 相似文献
217.
Chandra S Rai Shiv K Sharma David W Muenow Dean W Matson Charles D Byers 《Geochimica et cosmochimica acta》1983,47(5):953-958
The temperature dependence of carbon dioxide solubility in glasses of diopside composition, quenched from 20 kbar, has been investigated using a combination of high-temperature mass spectrometry and Raman spectroscopy.CO2-charged diopside glasses were synthesized in a piston-cylinder apparatus. Because of diffusion of hydrogen through the platinum capsules, significant amounts of H2O, CH4 and CO were detected along with CO: in the diopside glasses. All three carbon species show a bimodal release pattern in the mass pyrograms. The CO2 solubility shows a linear and negative temperature dependence. We do not observe any maxima in the solubility curve as was reported previously (Mysen and virgo, 1980a).None of the additional bands observed in Raman spectra of CO2-charged diopside glasses compared to those in the spectrum of diopside glass can be assigned to molecular CO2. These bands are caused by CO?23 ions and indicate that the physical solubility of molecular carbon dioxide is negligible. The bimodal release pattern observed for CO2 in the mass pyrograms, is consistent with the Raman data which strongly suggests that CO?23 ions are present in at least two distinct sites in the glass. 相似文献
218.
BarnaBahadur THAPA Saroj PANTHI Rajesh KumarRAI UttamBabu SHRESTHA Achyut ARYAL Sabina SHRESTHA Bhushan SHRESTHA 《山地科学学报》2014,11(2):555-562
Yarsagumba (Ophiocordyceps sinensis), an endemic species to the Himalayas and Tibetan Plateau, is one of the most valuable medicinal mushrooms in the world. In Nepal, it is distributed largely in isolated patches of alpine grasslands of 3,000-5,000 m elevation. Although it is reported from 27 northernmost districts of Nepal, the local distribution pattern of this species is largely unknown. Furthermore, the collection system and local management regime of this species are not well documented. We conducted a field survey at Dhorpatan Hunting Reserve (DHR) among the different stakeholders in January-June 2012 to assess collection sites, patterns and trends and to understand the management regime. We estimated that about 75 kg of Yarsagumba is collected every year from DHR and the amount has been declining since 2008. To manage the resource, locals have initiated regulating the collection by issuing permits, taxing to the collectors, and monitoring the activities of harvesters with the help of park authorities. The revenue generated at local level from the permits has been used for community developmental activities. 相似文献
219.
Tushar Gupta Rajesh Rai Ashok Jaiswal B. K. Shrivastva 《Geotechnical and Geological Engineering》2014,32(3):705-712
The present paper discusses the impact of the geometrical parameters of the coal rib and the mine dump on the stability of the coal rib. The geometrical parameters such as the slope angle, the height of dragline dump, the height of main dump, the gradient of seam and the thickness of coal rib have been considered as input to the numerical model for the stability analysis of the coal rib. Sensitivity analysis has been performed based on the results of the analysis in term of factor of safety of the coal rib. The input parameters have been classified in terms of significance (i.e. very high significance, high significance medium significance and low significance). The factor of safety is more influenced by highly significant parameters. The height and the slope angle of dragline dump and the thickness of the coal rib are highly significant parameters for the stability of the coal rib. The gradient of the seam is a medium significant parameter whereas, height of main dump and the number of dragline cut dump are low significant parameters for stability of coal rib. 相似文献
220.
The fast growth in population and expansion of urban built area has led to the transformation of the natural landscape into impervious surfaces. Remote sensing-based estimate of impervious surface area (ISA) has emerged as an important indicator for the assessment of water resources depletion in urban areas and developed a correlation between land-use change and their potential impact on urban hydrology. In the present work, a remote sensing-based Impervious Surface Area (ISA) was carried out for New Okhla Industrial Development Authority (NOIDA) city, one of the fastest growing cities in National Capital Region (NCR) of India. The impervious surface area (ISA) of NOIDA was calculated for the years 2001, 2007 and 2014 using multi-temporal LANDSAT thermal data by applying linear spectral mixing analysis (LSMA) techniques to monitor the growth rate of impervious surface. The results observed by analysis of multi-temporal satellite images show an extreme temporal change in the growth of ISA in the city. The ISA observed for the year 2001 is 28 sq.km; in 2007, its increase was 48 sq.km and was 132 in 2014. The results were observed from this work through the use of satellite data which is very important for water resource management, planning and prediction of ISA impact on hydrology. 相似文献