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31.
Seeds of Cicer arietinum L. plants are edible and a valuable source of protein. Accumulation of toxic metals in the edible part of the plant, grown in fields close to fly-ash (FA) landfills, may pose a threat to human health. In the present study, the effects of FA and its amendments with different ameliorants viz., garden soil (GS), press mud (PM) and saw dust (SD), on total soluble protein contents, amino acid composition and metal accumulation in seeds were investigated in var. CSG-8962 and var. C-235 of C. arietinum. Plants accumulated adequate amounts of essential metals viz. Fe, Cu, Zn in seeds, while the toxic metals such as Cd and Cr were taken up in smaller quantities. The accumulation of Cr and Cd was less in var. C-235 than var. CSG-8962. Amendment of FA with PM enhanced the amount of soluble protein and amino acids in both varieties and was found to be superior among all tested ameliorants. Both quantitative and qualitative analysis of amino acids showed better response in var. C-235 as compared to var. CSG-8962. Thus var. C-235 seems to be suitable for cultivation in FA contaminated areas due to more accumulation of essential metals and less accumulation of toxic metals in seeds. Application of PM may further improve the growth of plants and nutritional quality of seeds.  相似文献   
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33.
Tripathi RD  Vajpayee P  Singh N  Rai UN  Kumar A  Ali MB  Kumar B  Yunus M 《Chemosphere》2004,54(11):1581-1588
Plants of Cassia siamea Lamk were grown in garden soil (control), fly-ash (100%) and fly-ash amended by various ameliorants (cowdung manure, press-mud, garden soil; 1:1, w/w). The plants survived in fly-ash (100%) though their growth was less in comparison to the treatments. Fly-ash+press-mud (1:1, w/w) proved to be the best combination as growth (total biomass, leaf number, photosynthetic area, total chlorophyll and protein) was significantly high in this treatment followed by cowdung manure and garden soil. Leaves and roots accumulated significant amount of Cu, Zn, Ni and and Fe. However, the concentration of all the metals was more in roots than leaves except Ni. Although, fly-ash contains high amount of metals but the metal uptake was more in the plants grown in fly-ash+press-mud mixture. Inspite of high metal availability in fly-ash and press-mud mixture, plant growth was good. This might be attributed to the some metal detoxification mechanism active in this treatment. The present study concluded that C. siamea seems to be a suitable plant for developing a vegetation cover on fly-ash dumps.  相似文献   
34.
Biochar derived from partial combustion of vegetation is ubiquitous and potentially effective in sequestration of environmental contaminants.Biochars were prepared by burning of red gum(Eucalyptus spp.) woodchips at 450 and 850°C(labeled as BC450 and BC850).These two biochars were found to possess markedly different properties in terms of surface area and porosity.Short-term equilibration tests(24 hr) were conducted to assess the sorption-desorption behavior of pyrimethanil in the soil amended with various amounts of biochar of each type,with a special focus on the desorption behavior of the sorbed pesticide through four times successive desorption by dilution.Sorption coefficient and isotherm nonlinearity of the amended soils progressively increased with the content of biochar in the soil.Biochar BC850 with higher surface area and microporosity showed a stronger effect on the reversibility of sorption pesticide.The soils amended with 5% BC450 and 1% BC850 had nearly the same sorption capacity for pyrimethanil;however,their desorption processes were very different with 13.65% and 1.49% of the sorbed pesticide being released,respectively.This study suggested that biochar in soil could be an important factor for immobilization of a pesticide and thus affecting its environment fate in soil.  相似文献   
35.
In this work, a novel approach is proposed for expressing the risks of process plants consisting of a large number of scenarios, in the form of a risk metrics of leading indicators to prevent potential high profile industry accidents. The methodology includes: 1) risk estimation of a portfolio by CPQRA (or QRA), 2) monetization of the tangible risks with the inclusion of the lost time of production, 3) estimation of the maximum portfolio loss using Value-at-Risk approach, 4) inclusion of intangible risks using FN-curve and, 5) generation of F$-curve of tangible risks. The proposed methodology can particularly help in understanding the stakes at risk by performing the overall cost-benefit analysis, for identifying the most risky scenarios and identifying critical equipments to enable better risk-informed decision making in order to adopt appropriate risk mitigation measures. This work establishes the groundwork for developing measures for understanding and comparing the large number of risk values derived from QRA studies for large portfolios. It will aid in less subjective decision making as it enables the decision maker to choose the most preferred portfolio option among alternatives. Decisions made with the accurate understanding of the consequences of risks can significantly reduce potential work-related fatalities, property losses and save millions of dollars.  相似文献   
36.
Groundwater is the main source of drinking water and water for agricultural and industrial usage. Therefore, groundwater contamination is prevented and contaminated groundwater is remediated to protect public health and the environment. Methods to remediate groundwater contamination have been recently developed. The use of redox processes in water remediation technologies has not been properly reviewed. Numerous water remediation technologies, such as ultrasonication, bioremediation, electrokinetics and nanotechnology, are closely related to redox processes. Redox processes control the chemical speciation, bioavailability, toxicity, mobility and adsorption of water pollutants in environment. Here, we review (1) general introduction of redox processes, (2) applicability of redox processes in water remediation, and (3) catalytic enhancement of redox potentials to explore its wide applicability in environmental remediation.  相似文献   
37.
水体中磺胺甲恶唑和甲氧苄氨嘧啶的自然光降解   总被引:1,自引:0,他引:1  
实验研究了磺胺甲恶唑和甲氧苄氨嘧啶连续暴露于自然光下72 h,在pH值为4.0、7.0、9.0水体中的光降解行为,同时考察了黑暗条件下对照样品在不同pH条件下的稳定性.实验表明,光强、光照时间、水体pH都直接影响到磺胺甲恶唑的去除率.在自然光照环境下,不同pH溶液中的磺胺甲恶唑均易发生光降解,而黑暗对照样品去除率较小.甲氧苄氨嘧啶则比较稳定,几乎未发生降解,但黑暗对照样品在pH值为4.0和7.0的溶液中,与起始浓度相比,去除率大于10%,这可能主要与该药物在不同pH溶液中的离子形态及光照过程中的温度波动有关.  相似文献   
38.
We determined seasonal and spatial variation of zooplankton and their correlation with environment variables in a subtropical lake of the Himalayas. Thirty-eight species of zooplankton were identified, of which, 38.0% belonged to rotifera, 26.3% to cladocera, and 15.7% to copepoda. Nitrogen nutrients, total organic matter (TOM), and clay particles significantly influenced on the distribution pattern of zooplankton. Non-metric multidimensional scaling analysis showed homogeneous assemblages of dominant zooplankton species except Chydorus gibbus which has wider range of niche partitioning. Turbidity formed by suspended materials facilitated better avoidance of larger zooplankton like Daphnia similis from predators. Sedimentary silt particles influenced on the assemblages of sensitive species such as Tropocyclops prasinus, Asplanchna priodonta and Colurella obtuse. Changes within the land-use pattern in the catchment of the central Himalayan lakes either directly or indirectly impact on the distribution of zooplankton community.  相似文献   
39.
This study presents distribution of organochlorines (OCs) including HCH, DDT and PCBs in urban soils, and their environmental and human health risk. Forty-eight soil samples were extracted using ultrasonication, cleaned with modified silica gel chromatography and analyzed by GC-ECD. The observed concentrations of ∑HCH, ∑DDT and ∑PCBs in soils ranged between?<?0.01–2.54, 1.30–27.41 and?<?0.01–62.8 µg kg?1, respectively, which were lower than the recommended soil quality guidelines. Human health risk was estimated following recommended guidelines. Lifetime average daily dose (LADD), non-cancer risk or hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) for humans due to individual and total OCs were estimated and presented. Estimated LADD were lower than acceptable daily intake and reference dose. Human health risk estimates were lower than safe limit of non-cancer risk (HQ?<?1.0) and the acceptable distribution range of ILCR (10?6–10?4). Therefore, this study concluded that present levels of OCs (HCH, DDT and PCBs) in studied soils were low, and subsequently posed low health risk to human population in the study area.  相似文献   
40.
Alterations in the activity of enzymes Acid phosphatase (E.C.3.1.3.2) and Alkaline phosphatase (EC 3.1.3.1) in organs such as liver, gills and muscle of rohu following its exposure to surfactants viz. CTAB, SDS and Triton X-100 were analyzed. Different levels of exposure were given depending on the LC50 value of the surfactant used. Also, the influence of age and weight of the organisms was tested simultaneously. The activity of ACP in the tissues of fish exposed to all the three surfactants showed marked enhancement after exposure; the effect being highest in the liver followed by gill and muscle. Activity levels of ALP in different tissues of the fish exposed to the surfactants also showed an increase. Maximum increase was found in the liver followed by muscle, and gill. The increase in the levels of these enzymes indicates a stressful condition of the fish.  相似文献   
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