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961.
U. V. Gopala Rao 《Solar physics》1970,14(2):389-393
Homologous characteristics of radio bursts at 3000 MHz and associated optical flares are studied. It is found that flares associated with homologous radio bursts are also homologous optically.Published with the permission of the Director-General of Observatories, New Delhi. 相似文献
962.
The deep groundwater in the quaternary gravel sequence of the southern Upper Rhine Graben locally contains high chloride concentrations near the river Rhine between Fessenheim (France) in the South and Breisach (Germany) in the North. This historical pollution is mainly due to past infiltration from the former brine storage basins of the French potash mines on the Fessenheim Island and—to a lesser extent—from the leaching of the salt dumps of the German potash mines in Buggingen and Heitersheim. The spreading of the salt plume was investigated by means of a groundwater model. The aim of the model was to understand the brine movement, the present distribution of chloride as defined by recent hydrochemical investigations, and to select locations for new reconnaissance boreholes. The geological structure was reproduced by a three layer model, which was calibrated for steady state flow conditions. The hydraulic conductivity of the first layer was determined by comparing measured and calculated heads in the model area. The vertical resolution was refined to simulate the density-dependent salt transport processes. The transport of the salt plumes was simulated over a 40-year period, starting at the beginning of brine storage in the 1950s. The relevant transport parameters have been estimated in a sensitivity analysis, where the simulated breakthrough curves of chloride concentration have been compared with the measured data. The results of the groundwater model indicate that brines containing approximately 1 million tons of chloride are still present at the bottom of the aquifer. These highly concentrated salt brines mix with fresh water from the upper part of the aquifer. This dispersive process leads to the formation of a plume of chloride-rich water extending downstream, where pumping wells for several local water supplies are located. 相似文献
963.
I. Kanu O. K. Achi O. U. Ezeronye E. C. Anyanwu 《International Journal of Environmental Science and Technology》2006,3(1):95-102
Seasonal variation in bacterial heavy metals biosorption from soap and brewery industrial effluent samples from Eziama River in Abia State were analyzed for Pb, Hg, Fe, Zn, As, and Mn, using atomic absorption spectrophotometry. Bioaccumulation of the metals by bacteria showed the following trend > Fe >Zn >As > Pb > Mn (Rainy Season) and Zn > Fe > Mn > As > Hg > Pb (Dry season). Statistical analysis using of variance (ANOVA) showed significant differences in concentrations of Pb, Hg, Fe, Zn, As, and Mn level between the sampling zones at Eziama River. Seasonal changes in heavy metal concentrations, showed increases in Pb, Fe, and As from 1.32 x 105 mg/L in the rainy season to 1.42 x 105 mg/L in the dry season. Fe increased from 40.35 x 105 mg/L to 42.1 x 105 mg/L, while As increased from 2.32 to 2.48 x 105 mg/L with a net increases of+56 and + 69 x 105 mg/L respectively. However, Hg, Zn, and Mn concentrations decreased in the rainy season from 40.54 x 105 mg/L to 39.24 x 105 mg/L, 1.65 to 0.62 x 105 mg/L respectively. 相似文献
964.
965.
T. Kitamura M. Matsuoka S. Miyamoto M. Nakagawa M. Oda Y. Ogawa K. Takagishi U. R. Rao E. V. Chitnis U. B. Jayanthi A. S. Prakasa-Rao S. M. Bhandari 《Astrophysics and Space Science》1971,12(2):378-393
Results of rocket observations of SCO X-1 over the spectral range of 220 keV are presented. The observations have been performed partly in India and partly in Japan under the collaboration of the three groups. The present results are compared with results of similar observations carried out by the LRL (Lawrence Radiation Laboratory) group. Some of these X-ray observations were accompanied by simultaneous optical observations. Relationships between the hardness of the X-ray spectrum and the X-ray intensity and between the hardness and the optical luminosity are compiled. The relationships among the parameters (temperature, density and size) which characterize the postulated isothermal cloud model of SCO X-1 are given. They indicate that SCO X-1 is characterized by a temperature of about 107–108K, a density of about 1016–1017 cm–3 and a radius of about 108–109 cm respectively. We further show that the temperature is inversely correlated with the size of the source; an increase in temperature corresponds to a decrease in the radius and an increase in density. 相似文献
966.
967.
968.
Salt weathering in deserts 总被引:1,自引:0,他引:1
969.
970.