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The major metabolite of 5-ethyl-2′-deoxyuridine in rats has been isolated and purified by preparative thick layer and column chromatography. By mass and 1H NMR spectroscopy, it was identified as 5-(1-hydroxyethyl) uracil; the structure was confirmed by comparison with an authentic sample. 相似文献
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The major metabolite of 1-propyl-3,5-diethyl-6-chlorouracil has been identified as 6,8-diethyl-2-methyl-tetrahydrooxazolo[3,2-c]pyrimidine-5,7(4H,6H)-dione. The biotransformation to this bicyclic barbituric acid derivative takes place via substitution of the chlorine by ß- and not by α-hydroxy group of the intermediate hydroxypropane. 相似文献
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S. N. Kaul T. Nandy C. V. Deshpande A. Srivastava S. Shastry L. Szpyrkowicz 《毒物与环境化学》2013,95(1-2):247-257
An attempt has been made to present the data relating to full scale application of evaporation‐incineration technology for containment of wastewater emanating from H‐acid (mono sodium salt of 1 amino‐8‐hydroxynapthalene 3,6‐disulphonic acid) production with recourse to zero wastewater discharge. The wastewater is acidic with high concentrations of COD and total dissolved salts and BOD/COD ratio of 0.11. NOx, SOx, SPM and CO from stack emissions are within the standards stipulated by the statutory bodies. 相似文献
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Human communities inhabiting remote and geomorphically fragile high-altitude regions are particularly vulnerable to climate change-related glacial hazards and hydrometeorological extremes. This study presents a strategy for enhancing adaptation and resilience of communities living immediately downstream of two potentially hazardous glacial lakes in the Upper Chenab Basin of the Western Himalaya in India. It uses an interdisciplinary investigative framework, involving ground surveys, participatory mapping, comparison of local perceptions of environmental change and hazards with scientific data, identification of assets and livelihood resources at risk, assessment of existing community-level adaptive capacity and resilience and a brief review of governance issues. In addition to recommending specific actions for securing lives and livelihoods in the study area, the study demonstrates the crucial role of regional ground-level, community-centric assessments in evolving an integrated approach to disaster risk reduction and climate change adaptation for high-altitude environments, particularly in the developing world. 相似文献
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Keoladeo National Park (KNP) is an important wintering ground for thousands of birds that undertake a perilous journey over the Himalaya to make a seasonal home in a wetland ecosystem. However, this wetland is now getting polluted by various types of contaminants such as pesticides because of the agricultural practices in the catchment area from where the park receives water. Keeping this in mind, the present study has been undertaken to assess the organochlorine pesticide (OCP) residues in the sediments inside and around KNP. Samples were collected from the different blocks of the park. The concentrations of α-HCH, β-HCH, γ-HCH, δ-HCH, S-HCH, aldrin, dieldrin, heptachlor, hept.epoxide, endosulfan-I, endosulfan-II, endo.sulfate, S-endosulfan, endrin, 4,4'-DDE, 4,4'-DDD, and DDT were quantified using gas chromatography with electron capture detection. Analysis showed that the samples were contaminated with the above mentioned pesticides and that the concentration of total OCPs in the sediments varied from 0.1173 (dieldrin) to 5.558 ppm (γ HCH) in the samples collected from inside the park, whereas a range of pesticides varying in concentration from 0.1245 (4,4'-DDD) to 7.54 ppm (γ HCH) was found in samples from outside the park. Residues of S-HCH and S-endosulfan were not detected in any of the sediment samples. The occurrence of pesticides inside the park is a major threat to the park's biodiversity. Eco-friendly agriculture practices with minimal use of inorganic chemicals are suggested to minimize the pesticide residue levels in the park. 相似文献
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In view of their sensitivity and importance, an ecological-economic analysis of wetlands has been carried out for various Indian states. Subsequently, the ecological wealths of different zones (north, south, east and west) have been computed and compared. Amongst states, Karnataka (7896.5 million US dollars yr(-1)), Gujarat (7689.4 million US dollars yr(-1)) and Andhra Pradesh (7670.9 million US dollars yr(-1)) are found to be the richest, whereas Nagaland (3.1 million US dollars yr(-1)), Meghalaya (5.9 million US dollars yr(-1)) and Sikkim (15.9 million US dollars yr(-1)) turn out to be the poorest. Amongst different zones, Southern Zone turns out to be the richest and the Northern Zone poorest. A ratio called ANR [Artificial (A) Wetland Wealth to Natural (N) Wetland Wealth Ratio (R)] has also been devised, which is the ratio of the ecological-economic values of artificial and natural wetlands. In other words, this ratio indicates the level of environmental concern of a given region. ANR ratio is found to be the highest for Madhya Pradesh (564.1) and Karnataka (159.8) states. 相似文献