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51.
Joshi L. M. Kotlia B. S. Kothyari G. Ch. Singh A. K. K. Taloor A. Upadhyay R. Dayal D. 《Geotectonics》2021,55(4):543-562
Geotectonics - The present study focuses on the neotectonics activity and related mass movement along the Eastern Ramganga River Basin (ERRB), Kumaun Himalaya, India. To understand the... 相似文献
52.
Devi Dayal Sinha Surya Narayan Mohapatra Padmini Pani 《Journal of the Indian Society of Remote Sensing》2012,40(4):649-668
The main objective of the present work is to delineate the groundwater potential zones in Bilari watershed of district Shivpuri, Madhya Pradesh. Remote Sensing data and GIS were used to delineate the groundwater potential zones of the area. IRS-1D (LISS III) data have been utilized to extract information on various themes such as geomorphology, structure, drainage and land use/land cover. Available lithology and soil maps have also been used. DEM has been generated from contours taken from Survey of India topographical maps in order to obtain the slope percentage and slope aspect of the area. The groundwater potential zones were delineated by weighted overlay analysis. The themes geology, geomorphology, slope and soil were considered and the weightages assigned to different classes of respective themes according to their role in groundwater potential. Finally, five groundwater potential zones viz., very good, good, moderate; poor and very poor were delineated for the study area. It was estimated that about 110.41?sq km area which forms 37.55% of the total area are in the zones of very poor, poor and moderate category and about 183.75?sq km (62.45%) in zones of good and very good category. 相似文献
53.
We discuss the expansion of the universe in the FRLW model assuming that the source of dark energy is either tachyonic scalar field or quintessence. The tachyonic scalar field with exponential and power-law potential (function of homogeneous scalar field ?) both gives exponential expansion of the universe. It is found that this behaviour is not distinguishable from the quintessence with respect to these potentials. 相似文献
54.
Edison Liang 《Astrophysics and Space Science》2005,298(1-2):211-218
We review the particle-in-cell simulation results related to the recently discovered particle acceleration mechanism called
the Diamagnetic Relativistic Pulse Accelerator, or DRPA. This mechanism may be relevant to the prompt gamma-ray emission of
gamma-ray bursts. It may also be testable with future laboratory experiments using ultra-intense lasers. 相似文献
55.
Lisse C. M. Fernández Y. R. A'hearn M. F. Kostiuk T. Livengood T. A. Käufl H. U. Hoffmann W. F. Dayal A. Ressler M. E. Hanner M. S. Fazio G. G. Hora J. L. Peschke S. B. Grün E. Deutsch L. K. 《Earth, Moon, and Planets》1997,78(1-3):251-257
We present infrared imaging and photometry of the bright, giant comet C/1995 O1 (Hale-Bopp). The comet was observed in an
extended infrared and optical observing campaign in 1996–1997. The infrared morphology of the comet was observed to change
from the 6 to 8 jet “porcupine” structure in 1996 to the “pinwheel” structure seen in 1997; this has implications for the
position of the rotational angular momentum vector. Long term light curves taken at 11.3 μm indicate a dust production rate
that varies with heliocentric distance as ∶ r−1.4. Short term light curves taken at perihelion indicate a rotational periodicity of 11.3 hours and a projected dust outflow
speed of ∶ 0.4 km s−1. The spectral energy distribution of the dust on October 31, 1996 is well modeled by a mixture of 70% silicaceous and 30%
carbonaceous non-porous grains, with a small particle dominated size distribution like that seen for comet P/Halley (McDonnell
et al., 1991), an overall dust production rate of 2 × 105 kg s−1, a dust-to-gas ratio of ∶5, and an albedo of 39%.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
56.
57.
The regional imbalance in the Malaysian economy has long been recognised and continues to be a problem for development planning. The federal government has attempted to promote banking in the less developed regions in order to generate economic growth. Bank branches in Malaysia have increased in number and have also become regionally more dispersed. However, the regional concentration of bank branches is strongly associated with individual incomes. Hence, the growth of banking in Malaysia appears to be demand‐following rather than supply‐leading. Nevertheless, the intentional promotion of banking is continuing and beginning to produce some encouraging results. 相似文献
58.
M. A. Rasheed M. Veena Prasanna M. Lakshmi T. Madhavi M. S. Kalpana D. J. Patil A. M. Dayal 《Journal of the Geological Society of India》2012,80(2):267-275
Surface adsorbed gas surveys and geo-microbiological surveys are well known techniques of petroleum exploration and aim towards risk reduction in exploration by way of identifying the areas warm with hydrocarbons and to establish inter-se exploration priorities amongst the identified warm areas. The thermogenic surface adsorbed gaseous hydrocarbons distribution patterns in petroliferous areas are considered to be a credible evidence for the upward migration of hydrocarbons. The present investigation aims to explore correlation between the adsorbed gas distribution pattern and microbial oxidizers in identifying the upward migration of hydrocarbons especially in the tropical black soil terrain of known petroliferous Mehsana Block of North Cambay Basin, India. A set of 135 sub-soil samples collected, were analyzed for indicator hydrocarbon oxidizing bacteria, adsorbed light gaseous hydrocarbons and carbon isotope ratios (13Cmethane and δ13Cethane). The microbial prospecting studies showed the presence of high bacterial population for methane (5.4 × 106 cfu/gm), ethane (5.5 × 106 cfu/gm), propane (4.6 × 106 cfu/gm) and butane oxidizing bacteria (4.6 × 106 cfu/gm) in soil samples. The light gaseous hydrocarbon analysis showed that the concentration ranges of C1, C2, C3, iC4 and nC4 are 402 ppb, 135 ppb, 70 ppb, 9 ppb and 18 ppb, respectively, and the value of carbon isotope ranges of methane ?29.5 to ?43.0‰ (V-PDB) and ethane ?19.1 to ?20.9‰ (V-PDB). The existence of un-altered petroliferous microseep (δ13C, ?43‰) of catagenetic origin is observed in the study area. Geo-microbial prospecting method and adsorbed soil gas and carbon isotope studies have shown good correlation with existing oil/gas fields of Mehsana. Microbial surveys can independently precede other geochemical and geophysical surveys to delineate area warm with hydrocarbons, and mapped microbiological anomalies may provide focus for locales of hydrocarbon accumulation in the Mehsana Block of Cambay Basin. 相似文献
59.
David A. H. Buckley Lilia Ferrario Dayal T. Wickramasinghe & Jeremy A. Bailey 《Monthly notices of the Royal Astronomical Society》1998,295(4):899-906
We report polarimetric, spectropolarimetric and photometric observations of the eclipsing ROSAT cataclysmic variable RX J0929.1−2404, which confirm that the system is a new polar (AM Herculis system). This brings the number of eclipsing polars to nine, with RX J0929.1−2404 being only the third such system above the period gap. Circular polarization variations from ∼−20 to 10 per cent are seen over the 3.39-h orbital period, with a minimum around the time of eclipse. The photopolarimetric data were modelled using arc-shaped cyclotron emission regions in a centred dipole geometry. Results imply that RX J0929.1−2404 is a 'two-pole' system, with one emission region partially visible at all orbital phases. Spectropolarimetry observations show some evidence for the presence of cyclotron humps in the continuum, with spacings consistent with a magnetic field strength of ∼20 MG. Photometry of the eclipses provides information on the size of the emission region, which is consistent with a hotspot on the surface of the white dwarf. The eclipse duration implies an inclination in the range 70°≲ i ≲78°. 相似文献
60.