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391.
392.
Abate Rediat Hetharua Buce Hanoch Patil Vishal Lin Daner Kifle Demeke Liang Junrong Chen Changping Sun Lin Kao Shuh-Ji Bi Yonghong Huang Bangqin Gao Yahui 《中国海洋湖沼学报》2023,41(1):203-214
Journal of Oceanology and Limnology - The response of phytoplankton and its satellite bacteria to various concentrations (0.01%–10% v/v) of ethanol is studied. To elucidate the effect of... 相似文献
393.
Soil erosion modeling of a Himalayan watershed using RS and GIS 总被引:4,自引:1,他引:4
Ashish Pandey Abhisekh Mathur S. K. Mishra B. C. Mal 《Environmental Earth Sciences》2009,59(2):399-410
Employing the remote sensing (RS) and geographical information system (GIS), an assessment of sediment yield from Dikrong
river basin of Arunachal Pradesh (India) has been presented in this paper. For prediction of soil erosion, the Morgan-Morgan
and Finney (MMF) model and the universal soil loss equation (USLE) have been utilized at a spatial grid scale of 100 m × 100 m,
an operational unit. The average annual soil loss from the Dikrong river basin is estimated as 75.66 and 57.06 t ha−1 year−1 using MMF and USLE models, respectively. The watershed area falling under the identified very high, severe, and very severe
zones of soil erosion need immediate attention for soil conservation. 相似文献
394.
395.
Climate change has affected the temperature and rainfall characteristics worldwide. However, the changes are not equal for all regions and have localized intensity and must be quantified locally to manage the natural resources. Orissa is an eastern state in India where agricultural activities mainly depends on the rainfall and thus face problems due to changing patterns of rainfall due to changing climate. In the present study, attempts were made to study temporal variation in monthly, seasonal and annual rainfall over the state during the period from 1871 to 2006. Long term changes in rainfall characteristics were determined by both parametric and non-parametric tests. The analysis revealed a long term insignificant decline trend of annual as well as monsoon rainfall, where as increasing trend in post-monsoon season over the state of Orissa. Rainfall during winter and summer seasons showed an increasing trend. Statistically monsoon rainfall can be considered as very dependable as the coefficient of variation is 14.2%. However, there is decreasing monthly rainfall trend in June, July and September, where as increasing trend in August. This trend is more predominant in last 10?year. Based on departure from mean, rainfall analysis also showed an increased number of dry years compared to wet years after 1950. This changing rainfall trend during monsoon months is major concern for the rain-fed agriculture. More over, this will affect hydro power generation and reservoir operation in the region. 相似文献
396.
Anoop Kumar Mishra Rakesh M. Gairola Vijay K. Agarwal 《Journal of the Indian Society of Remote Sensing》2012,40(1):65-74
In the present study an attempt has been made to improve the rainfall estimation technique developed recently by Mishra et
al. (2009a, 2009b) based on KALPANA and Tropical Rainfall Measuring Mission (TRMM)-Precipitation Radar (PR) data over the Indian land and oceanic
region. The algorithm for rainfall estimation was basically based on synergistically analyzing the thermal infra-red radiances
from Kalpana/INSAT data along with the high resolution, horizontal and vertical rainfall estimates from PR. Presently the
augmentation is based on the data base of precipitable water and relative humidity from National Centre for Environmental
Prediction-Global forecast System (NCEP-GFS) data as a background field to correct for the biases in earlier algorithm. The
algorithm is tested for many case studies of monsoon rainfall over India and adjoining oceanic regions. The rainfall from
the present scheme is compared with the standard TRMM-3B42 rain product. The validation with the Automatic Weather Station
(AWS) rain gauge and the Global Precipitation and Climatology Project (GPCP) version 2 rain products shows that the present
scheme is able to retrieve the rainfall with a very good accuracy. These studies are aimed at the rainfall retrievals in near
future from both INSAT-3D and Megha-Tropiques, IR and MW imagers respectively. 相似文献
397.
Arpita Pankaj Pankaj Kumar Ajai Mishra 《Journal of the Indian Society of Remote Sensing》2012,40(4):725-734
Tons basin has the maximum share of glaciers, more than 50 glaciers, as well as glacierised area in Uttarakhand and Himachal Pradesh and the majority of the glaciers are of valley type. One of the important features of the glaciers of Tons valley is the presence of a thick mantle of supraglaciers moraine cover which can be attributed to the terrain characteristics, besides, the avalanche fed nature of the glaciers. The present study is the extraction of Glacio-geomorphological unit of Tons River basin based on the visual interpretation of remote sensing data. It was very much difficult in field, to extract all glacio-geomorphological units in glaciated area, but based on the remote sensing data, it becomes easy to identify. With the help of glacio-geomorphological map it has been found that four most important glaciers which fed the Tons River are Bandarpunch Glacier, Jaundar Bamak glacier, Jhajju Bamak and Tilku glacier. The tributaries of Tons River i.e. Harkidun Gad, Rupin Nadi and Supin Nadi are mainly fed by the mountain glaciers, valley glaciers and glacier lakes. The erosional terraces, glacio-fluvial terraces, open ??U?? shaped valleys, proglacial lake, lateral moraines, terminal moraines, palaeo-cirque and debris/talus cones are well developed in this glaciated regions. Glacio-geomorphic features are very much significant for palaeo-climatic reconstruction, showing variations, temporally and spatially. At the same time, these landforms, which are also altered by processes prevailing during interglacial period, helps in the geo-environment studies and glacier related problems like avalanches, global warming and cloudburst etc. 相似文献
398.
Uniformity in sulfur isotope composition in the orogenic gold deposits from the Dharwar Craton,southern India 总被引:1,自引:0,他引:1
The sulfur isotope composition of sulfides (mainly pyrite and arsenopyrite) from gold deposits/prospects of the Dharwar Craton
such as Hutti, Hira-Buddini, Uti, Kolar (Chigargunta), Ajjanahalli, and Jonnagiri has a narrow range (δ34S = +1.1 to +7.1‰). Such craton-scale uniformity of the above gold camps is noteworthy, in spite of the wide diversity in
host rock compositions and their metamorphic conditions, and suggests a magmatic or average crustal source of sulfur for all
deposits studied. In addition, our study points towards gold precipitation from reduced ore fluids, with near-homogeneous
sulfur isotope compositions. 相似文献
399.
We present a simulation based study of multiscale roughness of road surfaces and its effect on riding comfort in vehicles,
given the fact that characterization of the measured roughness is important to ensure smooth ride. Self-affine fractals are
used to simulate typically measured roughness data. Multiscale characteristics of such surfaces are obtained through varied
level of spatial resolutions. The hierarchical nature of the multiscale fractal roughness and their role in affecting the
riding comfort is investigated herein. Wavelet transform technique is exploited for multiscale decomposition. Roughness is
synthesized from cumulation of scales in a multiscale fashion. Single degree of freedom car model is used for characterizing
riding comfort parameters in terms of dynamic response of vehicle suspension system subjected to jerks exerted by rough profiles.
The dominant scales of roughness governing the comfort parameters are identified through parametric study. It is shown that
not all the scales are equally important in deciding the comfort parameters; rather, these parameters remain nearly intact
with the inclusion of only a few initial scales. This facilitates multiscale visualization of roughness data and allows representing
the profiles in a precise form by excluding the spurious higher scales. Apparently, it gives an economic estimate of the required
resolution in the physical measurement for specific purpose. 相似文献
400.