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121.
Analysis of Families of Triple Close Approaches Occurring inStellar Systems in Three Dimensions (II)
This is the second paper of a trilogy dealing with the role of triple encounters with low initial velocities and equal masses
in the evolution of stellar systems in three dimensional space. It shows how a condition of complete collapse may be perturbed
to obtain well-established families of asymmetric triple close approaches with systematic regularity of escape with the formation
of a binary. The main result is that when perturbation is introduced two close approaches called the first close approach
and the second close approach occur in the same plane but the binary formed and the escaper are not in that plane. Further
it is observed that the conjecture of Szebehely (1977) viz. `The measure of escaping orbits is significantly higher than the
measure of stable orbits' is likely to be true. The third and last paper offers applications in stellar systems.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
122.
123.
Shakti Suryavanshi Ashish Pandey Umesh Chandra Chaube Nitin Joshi 《Theoretical and Applied Climatology》2014,117(3-4):403-418
In this study, trend analyses of historic past climatic variables were investigated for the Betwa basin located in Central India. In the serially independent climatic variables, Mann–Kendall test (MK test) was applied to the original sample data. However, in the serially correlated series, pre-whitening is used before employing the MK test. The long-term trend analysis showed several of the meteorological stations to exhibit a decreasing trend in annual and seasonal precipitation in the study area. Seasonal and yearly numbers of rainy days are decreased. However, onset of effective monsoon (except for Shivpuri and Tikamgarh stations) did not show any trend during the study period. For maximum temperature, five out of 12 stations showed a decreasing trend in monsoon season whereas almost all other stations showed an increasing trend in winter and no trend in summer season. For minimum temperature, only two stations of the basin showed a decreasing trend in monsoon and all other stations exhibited a significant increase in winter and summer season. The increase of winter temperature may adversely affect the growth of Rabi crop (wheat and mustard) in the study area. Potential evopotranspiration (PET) did not show any trend in monsoon, except for Jalaun and Jhansi stations, showing decreasing trends. Raisen and Vidisha stations showed an increasing trend in winter only, and the trend for other stations were random in nature. In summer, five out of 12 stations showed an increasing trend in PET. Results of this study can be employed in preparation of water resources development and management plan in the Betwa Basin. 相似文献
124.
Hari B. Srivastava Vaibhava Srivastava Rajesh K. Srivastava Chandra Kant Singh 《Journal of the Geological Society of India》2011,78(1):45-56
In Kameng Valley of Arunachal Pradesh, the crystalline rocks of Se La Group of Higher Himalaya are thrust over the Lesser
Himalayan rocks of Dirang Formation, Bomdila Group along the Main Central Thrust and exhibit well preserved structures on
macro- to microscopic scales. Detailed analysis of structures reveals that the rocks of the area have suffered four phases
of deformation D1, D2, D3 and D4. These structures have been grouped into (i) early structures (ii) structures related to progressive ductile thrusting and
(iii) late structures. The early structures which developed before thrusting formed during D1 and D2 phases of deformation, synchronous to F1 and F2 phases of folding respectively. The structures related to progressive ductile shearing developed during D3 phase of deformation, when the emplacement of the crystalline rocks took place over the rocks of Dirang Formation along the
Main Central Thrust. Different asymmetric structures/kinematic indicators developed during this ductile/brittle-ductile regime
suggest top-to-SSW sense of movement of the crystalline rocks of the area. D4 is attributed to brittle deformation. Based on satellite data two new thrusts, i.e. Tawang and Se La thrusts have been identified
parallel to Main Central Thrust, which are suggestive of imbricate thrusting. Strain analysis from the quartz grains of the
gneissic rocks reveals constriction type of strain ellipsoid where k value is higher near the MCT, gradually decreases towards
the north. Further, the dynamic analysis carried out on the mesoscopic ductile and brittle-ductile shear zones suggest a NNE-SSW
horizontal compression corresponding to the direction of northward movement of Indian Plate. 相似文献
125.
After the landfall of Cyclone Sidr along the southwestern coast of Bangladesh on November 15, 2007, emergency and public health
personnel within and beyond Bangladesh anticipated a massive outbreak of water-borne and other diseases in most affected areas.
Fortunately, such an outbreak did not occur. The objectives of this paper are to examine the extent and pattern of illnesses
experienced by Cyclone Sidr survivors in the aftermath of its landfall and to investigate household and individual-level factors
associated with such illnesses. Based on face-to-face interviews conducted among 277 randomly selected Sidr survivors living
in the four most severely impacted coastal districts, this study found that the post-cyclone incidence of water-borne, respiratory,
and other diseases was not unusually high. Only 52 persons suffered Sidr-related illnesses, and their illnesses were significantly
associated with household income, and gender and age of the Sidr survivors. A major outbreak of such diseases was largely
avoided because of the proper distribution of food and safe drinking water, as well as the timely implementation of health
care intervention measures. This important finding will aid relevant authorities in successfully responding to outbreaks of
diseases following a future extreme event in Bangladesh and perhaps elsewhere. 相似文献
126.
Sneh Joshi Kireet Kumar Bimal Pande Mukesh Chandra Pant 《Meteorology and Atmospheric Physics》2013,120(3-4):177-187
The present study is an attempt to analyse the precipitable water vapour (PWV) derived from Global Positioning System (GPS) and observed meteorological data over Almora, Central Himalayan Region. The PWV values derived using GPS study is compared with the corresponding moderate resolution imaging spectro-radiometer (MODIS) data. The statistical analysis reveals a positive correlation between both methods. Moderate resolution imaging spectroradiometer near-infrared (MODIS NIR) clear column water vapour product shows a higher correlation (R 2 = 90–93 %) with GPS-derived precipitable water vapour on annual scale as compared to the seasonal scale (R 2 = 62–87 %). MODIS is found to be overestimating in NIR clear column where the magnitude of bias and RMSE show systematic changes from season to season. Monsoon is an important phenomenon in the Indian weather context and holds significant importance in Central Himalayan ecosystem. The monthly and seasonal variation in precipitable water vapour is related with monsoon onset in the region. Diurnal variations in precipitable water vapour are studied with other meteorological data over Almora during dry and wet season. The precipitable water vapour had minimum value in the morning, increases in the afternoon to evening and again decreases to the midnight in both the dry and wet seasons. These results suggest that diurnal variation of water vapour is caused by the transport of water vapour by thermally induced local circulation. 相似文献
127.
Recent claims of small icy comets disintegrating in the high atmosphere point to a component of comets in the form of loose
aggregates of dust. This could be understood in terms of Lyttleton;'s theory of comet formation by accretion of interstellar
grains.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
128.
Navin Chandra 《Planetary and Space Science》2004,52(8):747-760
The non-linear stability of the triangular libration point L4 of the restricted three-body problem is studied under the presence of third- and fourth-order resonances, when the more massive primary is a triaxial rigid body and source of radiation. In this study, Markeev's theorems are applied with the help of Moser's theorem. It is found that the stability of the triangular libration point is unstable in the third-order resonance case and in the fourth-order resonance case, this is stable or unstable depending on A1 and A2, and a source of radiation parameter α, where A1, A2 depend upon the lengths of the semi-axes of the triaxial rigid body. 相似文献
129.
Suresh Chandra 《Astrophysics and Space Science》1987,138(1):221-226
The Test-Run Output of erratum notice published by Jain and Thompson (1985) for their paper (Jain and Thompson, 1983) appears to be inconsistent. Hence, their computer programme needs a further modification.This paper was prepared while the author was a guest of the USSR Academy of Sciences at the A. F. Ioffe Physico-Technical Institute, Leningrad, U.S.S.R. 相似文献
130.
Jagdish Chandra Gupta 《Astrophysics and Space Science》1974,31(1):81-101
Geomagnetic data for the year 1967 from seven Canadian observatories, spanning the subauroral, auroral and polar zones, have been analysed to investigate the characteristic variation of Pc5 period with several geophysical variables. Pulsations in the whole spectrum of Pc5 (period range 150–600 s) were found to occur at all of the observatories. Those with smaller periods occurred more frequently at lower latitudes while those with longer periods occurred more frequently at higher latitudes. Daily variation of the periods of Pc5 showed little change with seasons or with magnetic activity. Periods, in general, had two daily maxima which appeared at different local times in different zones. A predominant morning peak was noted at all stations except Baker Lake, where a mid-day maximum of the period was found. The Pc5 periods tended to increase with geomagnetic activity at lower latitude stations, and to decrease with activity at stations in the polar cap for low to moderateKp levels. At high activity levels these trends appeared to reverse, though results are less certain. In different seasons and for the whole year the periods increased almost linearly with latitude. However when similar analysis was done for individual hours of the day and for different magnetic activity groups, this linear relationship between period and geomagnetic latitude was not evident. Efforts to detect a 27-day recurrence tendency of Pc5 periods did not succeed.Contributions from the Earth Physics Branch No. 495. 相似文献