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21.
The present rice‐dominated cropping system in the Hirakud canal command (eastern India) is under severe threat due to imbalance between irrigation water supply and demand. The canal water supply, which is the only source of irrigation, only meets 54% of the demand at 90% probability of exceedance (PE). In order to mitigate the irrigation water deficit from canal water, groundwater is considered as a supplemental source. Quasi‐three‐dimensional groundwater flow simulation modelling was, therefore, carried out by using Visual MODFLOW to detect the change in hydraulic head due to transient pumping stresses. The simulation model was calibrated and validated satisfactorily. Sensitivity analysis of the model parameters shows that groundwater recharge is most sensitive followed by aquifer hydraulic conductivity at almost all the sites of the command area, whereas the model is comparatively less sensitive to specific storage and specific yield. Enhanced pumping scenarios showed that groundwater extraction can be increased up to 50 times of the existing pumping without causing any adverse effect to the aquifer but the aquifer does not permit to exploit water in order to fulfill the irrigation water demand even at 10% PE. Hence, it is imperative to develop an optimal land and water resources management plan of the command area. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
22.
Correlation coefficients are calculated from the available geothermic data for the sedimentary basins of India to reveal some significant association between: (1) heat flow and thermal conductivity, (2) heat flow and geothermal gradient, (3) geothermal gradient and thermal conductivity, and (4) heat flow and related crustal thickness. The observed negative correlationship between heat flow and thermal conductivity for all Indian sedimentary basins suggests corresponding changes in crustal thickness.  相似文献   
23.
Syntans are synthetically prepared tanning agents from phenols that play an important role in leather making by enhancing the filling, grain characteristics and dyeing property. A considerable amount of syntan emanated in waste water contributes high pollution load with other heterocyclic aromatic compounds and causes serious environmental impact resulting in high oxygen demand. In order to overcome this, suitable biodegradation techniques have been developed using laccase from Penicillium chrysogenum. The influence of different environmental parameters on the biodegradation has also been studied which reveals that the maximum syntan degradation was obtained at pH 5.0, temperature at 32 °C for the duration of 48 h. Maximum biodegradation was found to be 96 and 94% for samples containing phenolic and melamine syntan. Ultraviolet spectra showed the peaks at around 280 nm for the presence of phenolic (DI) syntan and at 220 nm for melamine syntan which were disappeared later in the experimental sample indicating complete degradation of syntans. Fourier spectral analysis indicated that the peaks at the region between 1443–1574 and 1176 cm?1 correspond to C=C stretching and C–H bending for aromatic region which were later disappeared in the experimental sample. Ultrapressure liquid chromatography elution profiles of syntans showed relatively shorter retention time indicating formation of oxidized products. Syntans, namely DI and FB6, showed reduction in chemical oxygen demand up to 87.71 ± 4 and 83.38 ± 5%, respectively, while total organic carbon reduction was achieved up to 82.37 and 80.72%, respectively. Toxicity studies revealed that seeds were well germinated using the treated (biodegradation) samples by crude laccase .  相似文献   
24.
Most rural areas in the developing countries lack access to qualified out-patient (OPD) care. The gap in health services provision arises, due to lack of qualified doctors and is oftentimes filled by unqualified doctors who are also known as private non-degree practitioners (PNDPs). Despite their dominance, their presence is often neglected in access to health care studies. This leaves a scenario which lacks informal, but predominant, care. This paper uses a mix-method approach, combining exhaustive quantitative census of all health care providers along with location details in Geographic Information System to address the accessibility to PNDP. Longitudinal quantitative as well as spatial surveys were conducted for 3 years (2010, 2012 and 2013) in districts of Pratapgarh and Kanpur Dehat in state of Uttar Pradesh and Vaishali in Bihar state. The results of this study show that PNDPs account for 25 % of the all health care providers active across the study areas. The PNDPs are active in a radius of 2–5 km and are main workforce for the OPD care. Considering all health care providers PNDPs provide best potential accessibility to OPD care. If the PNDPs are removed from the scenario; remote areas will be the most affected ones, leaving them with almost no OPD care.  相似文献   
25.
The transient and steady-state solution of the linear heat transfer equation considering the rate of compaction of sediments and the vertical migration of interstitial water are obtained, respectively, for a single layer and a multi-layer model of unconsolidated sediments. At steady state the temperature profile with depth becomes a convex curve rather than a straight line due to the presence of above factors. The time needed to reach the steady state is observed to be directly proportional to the square of the thickness of the layer. The thermal gradient at the surface increases parabolically with the increase in the rate of the above-mentioned factors.The application of the steady-state results to the bore hole in Amchitka Island (Sass and Munroe, 1970) suggests that the observed surface heat flow value differs by 14% from the calculated one. Also the heat flow value at greater depth is calculated to be 2.02 · 106 cal cm 2s1, which is close to the mean value for Phillippine Trench (Nagasaka et al., 1970).  相似文献   
26.
Theoretical and Applied Climatology - Temperature and CO2 are the two most important climate parameters that affect crop yield directly. In this study, the impact of these two parameters on the...  相似文献   
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An adequately tested soil and water assessment tool (SWAT) model was applied to the runoff and sediment yield of a small agricultural watershed in eastern India using generated rainfall. The capability of the model for generating rainfall was evaluated for a period of 18 years (1981–1998). The watershed and subwatershed boundaries, drainage networks, slope, soil series and texture maps were generated using a geographical information system (GIS). A supervised classification method was used for land‐use/cover classification from satellite imageries. Model simulated monthly rainfall for the period of 18 years was compared with observations. Simulated monthly rainfall, runoff and sediment yield values for the monsoon season of 8 years (1991–1998) were also compared with their observed values. In general monthly average rainfall predicted by the model was in close agreement with the observed monthly average values. Also, simulated monthly average values of surface runoff and sediment yield using generated rainfall compared well with observed values during the monsoon season of the years 1991–1998. Results of this study revealed that the SWAT model can generate monthly average rainfall satisfactorily and thereby can produce monthly average values of surface runoff and sediment yield close to the observed values. Therefore, it can be concluded that the SWAT model could be used for developing a multiple year management plan for the critical erosion prone areas of a small watershed. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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Satellite detection of earthquake thermal infrared precursors in Iran   总被引:4,自引:1,他引:4  
Stress accumulated in rocks in tectonically active areas may manifest itself as electromagnetic radiation emission and temperature variation through a process of energy transformation. Land surface temperature (LST) changes before an impending earthquake can be detected with thermal infrared (TIR) sensors such as NOAA-AVHRR, Terra/Aqua-MODIS, etc. TIR anomalies produced by 10 recent earthquakes in Iran during the period of Jun 2002–Jun 2006 in the tectonically active belt have been studied using pre- and post-earthquake NOAA-AVHRR datasets. Data analysis revealed a transient TIR rise in LST ranging 2–13°C in and around epicentral areas. The thermal anomalies started developing about 1–10 days prior to the main event depending upon the magnitude and focal depth, and disappeared after the main shock. In the case of moderate earthquakes (<6 magnitude) a dual thermal peak instead of the single rise has been observed. This may lead us to understand that perhaps pre-event sporadic release of energy from stressed rocks leads to a reduction in magnitude of the main shock. This TIR temperature increment prior to an impending earthquake can be attributed to degassing from rocks under stress or to p-hole activation in the stressed rock volume and their further recombination at the rock–air interface. A precise correlation of LST maps of Bam and Zarand with InSAR-generated deformation maps also provides evidence that the thermal anomaly is a ground-related phenomenon, not an atmospheric one.  相似文献   
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