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51.
Climates of urbanization: local experiences of water security,conflict and cooperation in peri-urban South-Asia 总被引:1,自引:0,他引:1
Dik Roth Muhammad Shah Alam Khan Israt Jahan Rezaur Rahman Vishal Narain Aditya Kumar Singh 《Climate Policy》2019,19(6):S78-S93
ABSTRACTThis article explores changing water (in)securities in a context of urbanization and climate change in the peri-urban spaces of four South-Asian cities: Khulna (Bangladesh), Gurugram and Hyderabad (India), and Kathmandu (Nepal). As awareness of water challenges like intensifying use, deteriorating quality and climate change is growing, water security gets more scientific and policy attention. However, in peri-urban areas, the dynamic zones between the urban and the rural, it remains under-researched, despite the specific characteristics of these spaces: intensifying flows of goods, resources, people, and technologies; diversifying uses of, and growing pressures on land and water; and complex and often contradictory governance and jurisdictional institutions. This article analyses local experiences of water (in-)security, conflict and cooperation in relation to existing policies. It uses insights from the analysis of the case studies as a point of departure for a critical reflection on whether a ‘community resilience’ discourse contributes to better understanding these cases of water insecurity and conflict, and to better policy solutions. The authors argue that a community resilience focus risks neglecting important insights about how peri-urban water insecurity problems are experienced by peri-urban populations and produced or reproduced in specific socio-economic, political and policy contexts. Unless supported by in-depth hydro-social research, such a focus may depoliticize basically political questions of water (re) allocation, prioritization, and access for marginalized groups. Therefore, the authors plead for more critical awareness among researchers and policy-makers of the consequences of using a ‘community resilience’ discourse for making sense of peri-urban water (in-)security.Key policy insights
There is an urgent need for more (critical) policy and scientific attention to peri-urban water insecurity, conflict, and climate change.
Although a changing climate will likely play a role, more attention is needed to how water insecurities and vulnerabilities in South Asia are socially produced.
Researchers and policy-makers should avoid using depoliticized (community) resilience approaches for basically socio-political problems.
52.
The modes of oscillation of a twisted magnetic flux tube in an incompressible medium are investigated analytically. An exact dispersion relation for the case of uniform twist is obtained. In contrast to the case of an untwisted incompressible tube, body, surface, and hybrid (surface-body) modes arise. 相似文献
53.
Kamini Narain Taiyyaba Yazdani Mohd. Muzamil Bhat Mohmmad Yunus 《Environmental Earth Sciences》2012,66(3):977-984
Molasses-based distilleries are one of the most polluting industries generating large volume of wastewater. Distillery effluent
(DE) on its discharge alters the physical and chemical properties of the soil. This study has been conducted to assess the
distribution of heavy metals and its effect on physiochemical and structural changes of soil which has been treated with diluted
and undiluted effluents. The soil has been assayed both before and after crop plantation. Out of the crop plants studied,
Cicer
arietinum was least effected and more effective than Pisum
sativum in diminishing the heavy metals from soil. However, only at higher concentration DE has some adverse impact on the nutrient
contents of the soil. Fourier transform infrared spectrum (FTIR) study of the soil indicated the presence of –OH, –NH, –COOH
groups. It was also noted that the soil amended with different concentration of DE and on which Cicer and Pisum were grown has varied IR spectrum. These variations show the presence of different functional groups of soil before and after
plants were grown. The presence of inorganic carbonate was found in soil planted with Cicer from 10 to 50% of DE, whereas aliphatic primary amides were observed up to 25 and 100% concentrations of DE in soil planted
with Pisum. The appearance of inorganic nitrates, carbonates, aliphatic hydrocarbons and aliphatic primary amides at various concentrations
of DE showed a change in functional groups probably because of the differential breakdown of parent component present in the
effluent. Besides our main finding that Cicer is a very useful crop species in remediating the soil which has inflicted with even undiluted DE, it is also validated through
FTIR spectra that IR technique is an efficient tool in studying the structural changes of soil and with some degree of caution
may be summed up that FTIR may be used to correlate the relative efficacy of plants to transform organic contaminants. 相似文献
54.
Nishant Mittal Kumud Pandey Udit Narain S. S. Sharma 《Astrophysics and Space Science》2009,323(2):135-145
We have investigated properties such as speed, angular width, location, acceleration and occurrence rate of narrow CMEs (defined
as having angular width ≤20°) observed during 1996–2007 by SOHO/LASCO. The results obtained are compared with those of normal
CMEs (angular width >20°) from the same time interval to find whether there are any real differences between the two populations.
Our study of 3464 narrow CMEs from the online SOHO/LASCO, CME catalogue leads us to conclude that (1) the fraction of narrow
CMEs during solar minimum is 38% and during solar maximum 19%, (2) during solar maximum narrow CMEs are generally faster than
normal CMEs, (3) the maximum speed of narrow CMEs is much smaller than that of the normal CMEs, (4) during solar maximum narrow
CMEs appear at all latitudes similar to normal CMEs, (5) narrow and normal CMEs have unequal deceleration and (6) the occurrence
rate of narrow CMEs remain constant after 1998 until the beginning of 2006 while the normal CMEs occurrence rate seems to
follow solar cycle variation until 2004. Thus narrow CMEs and normal CMEs have some differences, in disagreement with previous
studies. 相似文献
55.
It is shown that the neglect of radiative losses by Antiochos and Sturrock (1976) in investigating conduction cooling is not justified. It is further shown that the anomalous current dissipation leads to substantial amount of heating contrary to remarks made by Ionson (1982). 相似文献
56.
Einstein's equations have been solved for perfect fluid distribution. The solution obtained may be considered as inhomogeneous generalisation of Bianchi type-VIo cosmological model. 相似文献
57.
58.
An improved value of the temperature in the solar corona for equal green and red line intensities is obtained. This temperature is in better agreement with a quoted line-width value than the previous theoretical ones. 相似文献
59.
Rishi Narain Singh 《Tectonophysics》1984,105(1-4)
The estimate of the paleothermal state (at −3 Ga) of the Indian shield is deduced using pressure and temperature estimates from the mineral assemblages combined with models of the heat transport mechanism and depth distribution of radiogenic heat in the crust. We find that at 3 Ga ago, the mean thermal gradient within the crust, reduced heat flow and mean mantle temperature were 28°C/km 1.08 h.f.u. and 2350°C, respectively. 相似文献
60.
Rishi Narain Singh 《Pure and Applied Geophysics》1973,109(1):1781-1788
Summary Forced hydromagnetic oscillations in the outer core due to stress at its top are studied by means of a simple linear theoretical model originally proposed byHide [1] for the free oscillation studies. Both the magnetic and the inertial modes are excited. The expressions for the velocity, magnetic and vorticity fields are presented for a variety of stresses. They depend upon the wave number and frequency. In a numerical example wherein the stress varies periodically both in the space and the time, the amplitude of the induced magnetic field is found to be significant for reasonable values of various parameters. 相似文献