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91.
92.
In the present work, histological changes in the gill, liver, kidney and intestine of Notopterus notopterus, induced by pulp waste, paper waste and mixed pulp and paper waste, have been studied both at sublethal and lethal concentrations. The pulp waste produces much more histological changes both at sublethal and lethal concentrations in the gill, liver, kidney and intestine as compared to paper waste and mixed pulp and paper waste. The changes are much more remarkable in the case of sublethal concentration, as compared to a lethal concentration. In a sublethal concentration, the localized necrosis, atrophy and partial and total liquefaction of epithelial cells, pilaster cells, mucous cells of the gill, hepatic cells of the liver, mesenchymatous cells, renal tubule cells and Bowman's capsule of the kidney, mucosal and submucosal cells and blood vessels of intestine have been observed. In lethal concentration, the changes are much more marked in the gill, as compared to the liver, kidney and intestine. The histological changes, produced in the different types of cells and in the tissue as a whole, can be correlated with the different chemical components present in the pulp waste, paper waste and mixed pulp and paper waste. 相似文献
93.
P. N. Shukla N. Bhandari V. N. Nijampurkar D. Kameswara Rao V. M. K. Puri Sanjiv Sharma 《Journal of Earth System Science》1983,92(3):255-260
Vertical profiles of137Cs and210Pb have been determined in a 9 m column of ice from accumulation zone of Changme-Khangpu glacier in north Sikkim valley.137Cs activity varies from 4 to 22 dpm/ L. In many samples210Pb occurs at a level of 20 to 65 dpm/ L which is much higher than the expected fallout value.137Cs and210Pb activities correlate well with each other but not with the dust content. Possibility of210Pb production in the nuclear explosions is discussed. Several peaks appear in the depth profile of137Cs and210Pb which can be matched with Chinese atmospheric nuclear explosions with some phase difference if a uniform ice accumulation
rate of 0.7 m per year is assumed since 1969. 相似文献
94.
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96.
Satellite data provides important inputs far estimating regional surface emisslviiy and surface temperature. The methodology for estimation of emissivity over heterogeneous areas is based on the calculation of fraction vegetation cover per pixel taking NDVI, reflectances of pure pixels as input. The surface temperature is calculated using a sptit-window equation, which depends on atmospheric water vapour, viewing angle and channel surface emissivities. In the present study model coefficients for atmospheric corrections to NOAA AVHRR thermal data Fqr tropical atmospheres have been derived with a view to operationally use the methodolpgy for generating land surface temperature information from satellite data. The results of the study show that the estimated temperature values are comparable with the ctimatological values over the region Suggesting the possible use of the methodology. 相似文献
97.
It is shown that dust-neutral and ion-neutral drags can produce instabilities of electrostatic waves in multicomponent self-gravitating dusty plasmas. Explicit expressions for the growth rates of the instabilities are presented. The relevance of our investigation to fragmentation of molecular dust clouds is discussed. 相似文献
98.
Padma K. Shukla 《Astrophysics and Space Science》1998,264(1-4):235-245
The status of waves and instabilities in magnetized dusty plasmas is summarized. The effects of an external magnetic field
on low-frequency electrostatic and electromagnetic waves in dusty plasmas are discussed. The kinetic and hydrodynamic instabilities
are shown to excite magnetized dusty plasma waves. The presence of the latter can give rise to an oscillatory wake-potential
which can be responsible for the charged dust grain attraction. The relevance of our investigation to laboratory and space
plasmas has been pointed out.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
99.
O.G. Onishchenko O.A. Pokhotelov P.K. Shukla L. Stenflo 《Astrophysics and Space Science》1998,262(3):249-262
The magnetic viscosity tensor is derived for a magnetized relativistic collisionless plasma with temperature gradients. By means of this tensor we deduce the nonlinear equations for drift–Alfvén waves in a relativistic electron-positron low plasma with density and temperature gradients. It is shown that our new equations have solutions in the form of dipolar vortices. The present results should be relevant to a number of astrophysical objects with strong electron-positron pair production, e.g. in pulsars as well as in accretion disks and jets. 相似文献
100.
The nonlinear excitation of low-frequency electrostatic waves by a high-power pump wave is re-examined. In that way, we present simple formulas that are relevant for ionospheric heating experiments. 相似文献