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31.
1-(4-Chlorophenyl))-N-hydroxymethanimine and cyclohexyl-N-hydroxymethanimine were synthesized and a well-established oxime, i.e., 2-[(hydroxyimino)methyl]-1-methylpyridinium chloride was purchased. Thereafter; all were loaded over Al2O3 using incipient wetness technique. The prepared systems were characterized using surface area analyzer, scanning electron microscope, energy dispersive X-ray spectrophotometer, Fourier transform infrared spectrophotometer and thermogravimetric analyzer. Kinetics of the degradation of sarin (GB) and simulant, i.e. diethylchlorophosphate (DEClP) was studied over synthesized oxime impregnated Al2O3 and results were compared with well reported oxime impregnated Al2O3. Kinetics of reaction was found to be following the pseudo first order reaction kinetics. The order of reactivity of the prepared systems was found to be cyclohexyl-N-hydroxymethanimine/Al2O3 > 1-(4-chlorophenyl)-N-hydroxymethanimine/Al2O3 > 2-[(hydroxyimino)methyl]-1-methylpyridinium chloride/Al2O3 > Al2O3. From the reaction kinetics it was observed that the reaction with DEClP was faster than with GB. Cyclohexyl-N-hydroxymethanimine/Al2O3 was found to be the most reactive system with half-life of 0.94 and 15 h for DEClP and GB respectively.  相似文献   
32.
Oral administration of arsenic trioxide(3 and 6 mg/kg body weight/d) for 30 d caused, as compared with vehicle control, dose-dependent significant reductions in body weight, absolute weight, protein, glycogen, as well as, total, dehydro and reduced ascorbic acid contents both in the liver and kidney of arsenic-treated mice. Succinic dehydrogenase(SDH) and phosphorylase only in the liver activities were significantly reduced in a dose-dependent manner. Acid phosphatase activity was significantly decreased in the liver of low dose arsenic-treated animals;however, significant rise in its activity was observed in high dose group. As compared with vehicle control, treatment also caused significant dose-dependent reductions in SDH, alkaline phosphatase and acid phosphatase activities in the kidney of mice. Vitamin E cotreatment as well as, 30 d withdrawal of arsenic trioxide treatment with or without vitamin E caused significant amelioration in arsenic-induced toxicity in mice. Administration of vitamin E during withdrawal of treatment also caused significant amelioration as compared from only withdrawal of the treatment. It is concluded that vitamin E ameliorates arsenic-induced toxicities in the liver and kidney of mice.  相似文献   
33.
Environmental Science and Pollution Research - The immune system protects human health from the effects of pathogenic organisms; however, its activity is affected when individuals become infected....  相似文献   
34.
Pollution of water bodies is one of the areas of major concern to environmentalists. Water quality is an index of health and well being of a society. Industrialization, urbanization and modern agriculture practices have direct impact on the water resources. These factors influence the water resources quantitatively and qualitatively. The study area selected were the Upper lake and Kolar reservoir of Bhopal, the state capital of Madhya Pradesh, India. The Upper lake and Kolar reservoir both are the important sources of potable water supply for the Bhopal city. The physico–chemical parameters like temperature, pH, turbidity, total hardness, alkalinity, BOD, COD, Chloride, nitrate and phosphate were studied to ascertain the drinking water quality.  相似文献   
35.
The enhanced concentration of methane (CH4) in the atmosphere is significantly responsible for the ominous threat of global warming. Rice (Oryza) paddies are one of the largest anthropogenic sources of atmospheric CH4. Abatement strategies for mitigating CH4 emissions from rice fields offer an avenue to reduce the global atmospheric burden of methane and hence the associated menace of climate change. Projections on population growth suggest that world rice production must increase to meet the population’s food energy demand. In this scenario, those mitigation options are advocated which address both the objectives of methane mitigation and increased production of rice simultaneously. In this paper, we have formulated a nonlinear mathematical model to investigate the effectiveness and limitations of such options in reducing and stabilizing the atmospheric concentration of CH4 while increasing rice yield. In modeling process, it is assumed that implementation rate of mitigation options is proportional to the enhanced concentration of atmospheric CH4 due to rice fields. Model analysis reveals that implementation of mitigation options not always provides “win-win” outcome. Conditions under which these options reduce and stabilize CH4 emission from rice fields have been derived. These conditions are useful in devising strategies for effective abatement of CH4 emission from rice fields along with sustainable increase in rice yield. The analysis also shows that CH4 abatement highly depends on efficiencies of mitigation options to mitigate CH4 emission and improve rice production as well as on the implementation rate of mitigation options. Numerical simulation is carried out to verify theoretical findings.  相似文献   
36.
Soil, water and species diversity relationships are central components of the vegetation ecology. In this connection, the present study was performed on the three sites within the campus of Banaras Hindu University of India, to relate herbaceous species diversity to soil physical characteristic and the intensity of biotic interferences. At each site, three, 10 m × 10 m plots were randomly established and within each plot, four quadrats each 50 cm × 50 cm were randomly placed for sampling. For each quadrat, number of individuals and their herbage cover were recorded by species. Soil physical characteristics (soil moisture, water-holding capacity, soil porosity and bulk density), elements of biotic interferences and α-diversity and its components were determined for each plot. The plots were ordinated by Non-metric Multidimensional Scaling (NMS) using Importance Value Indices of the component species. Results showed that the selected locations differed in terms of soil moisture and species diversity parameters due to differences in biotic interferences. NMS ordination yielded three groups corresponding to the three communities experiencing different intensity of land use. NMS axes were substantially related to the soil and herbaceous diversity parameters and suggested that the elements of soil physical characteristics, intensity of biotic interferences and regional herbaceous species pool had profound effect on the organization and determination of herbaceous floristic composition. Further, the sample locations exhibiting greater soil moisture, water-holding capacity, soil porosity and lesser soil bulk density harboured greater herbaceous diversity. A negative relationship between indices of species diversity and soil bulk density revealed that the dry and compact soils due to greater biotic pressure contributed to the loss of species diversity. Reduction in livestock numbers, grazing pressure and soil bulk density could be helpful in the promotion of soil quality and species diversity.  相似文献   
37.
38.
Environmental Science and Pollution Research - Water is an essential moiety for the human use since a long time. Availability of good-quality water is very essential, as it is used in almost all...  相似文献   
39.
Environmental Science and Pollution Research - Mining waste that is rich in iron-, calcium- and magnesium-bearing minerals can be a potential feedstock for sequestering CO2 by mineral carbonation....  相似文献   
40.
An experiment was conducted to assess the role of different concentrations of dicyandiamide (DCD), a potent nitrification inhibitor, on temporal changes in nitrous oxide emission from sandy loam agricultural soil. It was found that with increasing concentration of DCD i.e. from 6 to 12% of nitrogen applied in the form of urea, there was a decrease in the both average and peak N2O emissions. However, from 14% DCD treated soil, there was a non-significant alteration in the N2O emission. Maximum average N2O efflux of 217.55 μg m−2 h−1 was noted from control plots. As compared to control, there was an attenuation of 50, 58, 65, and 91% average N2O efflux from 6, 8, 10 and 12% DCD applied pots, respectively, whereas, there was a negative average of N2O efflux from the soil with 14% DCD treatment. The soil N content also showed a significant correlation with N2O emission. Therefore, 12% DCD treatment has been found to be the best with regard to attenuation of nitrous oxide from sandy loam agricultural soils.  相似文献   
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