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61.
Dumping of solid waste in a non-engineered landfill site often leads to contamination of ground water due to leachate percolation into ground water. The present paper assesses the pollution potential of leachate generated from three non-engineered landfill sites located in the Tricity region (one each in cities of Chandigarh, Mohali and Panchkula) of Northern India and its possible effects of contamination of groundwater. Analysis of physico-chemical properties of leachate from all the three landfill sites and the surrounding groundwater samples from five different downwind distances from each of the landfill sites were collected and tested to determine the leachate pollution index (LPI) and the water quality index (WQI). The Leachate Pollution Index values of 26.1, 27 and 27.8 respectively for landfill sites of Chandigarh (CHD), Mohali (MOH) and Panchkula (PKL) cities showed that the leachate generated are contaminated. The average pH values of the leachate samples over the sampling period (9.2 for CHD, 8.97 for MOH and 8.9 for PKL) show an alkaline nature indicating that all the three landfill sites could be classified as mature to old stage. The WQI calculated over the different downwind distances from the contamination sites showed that the quality of the groundwater improved with an increase in the downwind distance. Principal component analysis (PCA) carried out established major components mainly from natural and anthropogenic sources with cumulative variance of 88% for Chandigarh, 87.1% for Mohali and 87.8% for Panchkula. Hierarchical cluster analysis (HCA) identifies three distinct cluster types for the groundwater samples. These clusters corresponds to a relatively low pollution, moderate pollution and high pollution regions. It is suggested that all the three non-engineered landfill sites be converted to engineered landfill sites to prevent groundwater contamination and also new sites be considered for construction of these engineered landfill sites as the present dumpsites are nearing the end of their lifespan capacity.  相似文献   
62.
Environment, Development and Sustainability - Banking industries are blamed to be among the major factors that affect global climate change both directly and indirectly. The green banking concept...  相似文献   
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Environmental Science and Pollution Research - Solar power is one of the main sources of renewable energy which helps for protecting the environmental and reducing pollution. Technologies and...  相似文献   
64.
Conversion of broad-spectrum organic waste into carbonaceous biochar has gained enormous interest in past few years. The present study aims to characterize feedstock (FS), i.e. bagasse (Bg), bamboo (Bm) and biochar (BC), i.e. baggase biochar (BBg), bamboo biochar (BBm) and tyre biochar (Ty). Significant changes in elemental composition, atomic ratio, proximate analyses, mineral content and heavy metal content were observed which was well supported by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis. Impregnation with ferric hydroxide was done, and resultant modified biochars (MBC), i.e. iron-impregnated baggase biochar (FeBBg), iron-impregnated bamboo biochar (FeBBm) and iron-impregnated tyre biochar (FeTy), along feedstock and biochar were used for PO4 3?, Pb, Hg and Cu adsorption. In general, BBg, FeBBg, BBm, FeBBm, Ty and FeTy were found to adsorb PO4 3?, Pb, Hg and Cu better than Bg and Bm, except in few cases. Results from adsorption experiments were fitted into Langmuir, Freundlich and Temkin models of isotherms and pseudo-first-order, pseudo-second-order and Elovich models of kinetics. Result of batch study adsorption revealed that maximum adsorption of PO4 3?, Pb, Hg and Cu was done by FeBBg (adsorption mechanism explained by Freundlich model), FeTy (Temkin model), Ty (Langmuir model) and BBm (Langmuir model) respectively. According to R 2 values, pseudo-first-order reaction was well suited to PO4 3?, Pb, Hg and Cu adsorption. The optimum pH for maximum adsorption was observed to be 7.4 for PO4 3?, 5 for Cu and 6 for Pb and Hg respectively  相似文献   
65.
Environmental Science and Pollution Research - This research paper presents the results of an experimental investigation of the degradation of three different contaminants including progesterone...  相似文献   
66.
Alstonia scholaris or Indian devil tree is a common, evergreen, tropical tree of the Apocynaceae family. The objectives of this study were (a) to observe the seasonal variation of A. scholaris pollen in the atmosphere of an industrial and rural area of West Bengal, India by conducting a 2-year aerobiological survey with a Burkard personal volumetric sampler, (b) to study its allergenicity in the local population by in vivo (skin-prick test) and in vitro tests (enzyme-linked immunosorbent assay and dot blotting), (c) to identify the immunoglobulin E (IgE)-binding proteins present in the pollen extract (sodium dodecyl sulphate-polyacrylamide gel electrophoresis and immunoblotting), (d) to study its chemical composition. A. scholaris pollen were present in the air from September until November. They contained 14.3 % carbohydrate, 9.2 % lipid, and 4.3 % protein. Among 140 respiratory allergic local patients, 28.57 % showed positive skin reaction to A. scholaris pollen extract. Twelve protein bands in the range of 94.4–13.3 kDa were observed in the pollen extract. Seven IgE-binding proteins were found. Among them, one component of 29.9 kDa was the most important in A. scholaris pollen extract. This component could be purified and would be helpful in the diagnosis and therapy of A. scholaris pollen-susceptible patients.  相似文献   
67.
We have examined the effect of Hg2+ ions on DNA, RNA and collagen synthesis in organ cultures of neo-natal rat lungs. These cultures exhibit many biochemical characteristics of lung in vivo and they continue to synthesize macromolecules at increasing rates up to 6 days. When these cultures were exposed to 1.0μM HgC12, the synthesis of DNA was stimulated nearly 3-fold after 72 hr of exposure followed by a decline at 120 hr reflecting cumulative cytotoxicity. Higher concentrations were inhibitory at all times. A nearly 3-fold increase in RNA synthesis occurred after 24 hr exposure to 1.0 μM HgC12 and at 72 hr the cultures continued to synthesize RNA at rates comparable to control. There was a decrease in RNA synthesis at 120 hr. Increased collagen synthesis was observed at concentrations up to 10 μM and at all times. The maximal increase, 2–3 fold, occurred at 120 hr in cultures exposed to 0.1 M. These studies suggest that Hg2+-induced cell injury in lung organ cultures elicits a reparative response characterized by increased collagen synthesis. This is similar to chemically induced tissue-injury in lungs in vivo. The relevance of these data to the mechanism of induced pulmonary fibrosis is discussed. These studies also point to the usefulness of organ cultures for studying pulmonary toxicity of environmental agents.  相似文献   
68.
N-heterocyclics were separated from a biooil, generated by the pyrolysis of chicken manures by column chromatography over neutral alumina and silica, and identified by Pyrolysis Field Ionization Mass Spectrometry (Py-FIMS) and Electrospray Ionization Mass Spectrometry (ESI-MS). Identities of chemical structures, whose presence was indicated by ESI-MS, were confirmed by comparing the Collision-Induced Dissociations (CID's) mass spectra of unknown and standards. The following seven base structures were identified: pyrazine, benzoquinoline, carbazole, phenylpyridine, indole, pyrazole and pyridine. Available hydrogens bonded to ring carbons and nitrogens on the seven N-heterocyclics were increasingly substituted by alkyl groups, mainly methylene groups (m/z 14) to yield mono-, di-, tri- methyl N-heterocyclics. In some instances, longer alkyl chains, such as ethyl, propyl, up to heptyl groups were the substituents.  相似文献   
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