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211.
The physico-chemical characteristics of the drinking water in nine residential halls of the Aligarh Muslim University, Aligarh, U.P. (India), were studied. Nine samples each of running and standing water were taken four times over a period of one month at weekly intervals from all of the residential halls and were analysed for physico-chemical characteristics and heavy metal contents. The temperature, pH and electrical conductivity of water samples ranged between 20.0–26.0°C; 7.00–8.00 and 116.00–199.04 micromhos cm–1 respectively whereas the values of total alkalinity, total hardness, Cl, SO 4 , F, NH3–N, NO2–N; NO3–N were found between 261.00–396.00; 128.00–200.00; 8.00–69.00; 12.00–46.00; 0.90–1.35; 0.20–0.44; ND; 1.60–6.50 mg l–1 respectively. The ranges of heavy metal concentrations in the running water samples were as follows: Cd (0.70–3.75); Cr (ND-5.00); Co (9.50–18.75); Cu (0.75–15.00); Fe (ND-13.50); Mn (3.50–51.00); Ni (7.00–17.50); Pb (0.50–2.50) and Zn (10.00–176.50) g l–1. The heavy metal concentrations in standing water samples were found to be: Cd (1.20–4.90); Cr (ND-10.00); Co (10.25–19.00); Cu (1.75–20.00); Fe (ND-18.00); Mn (5.00–66.50); Ni (8.75–19.75); Pb (0.75–5.50) and Zn (28.60–364.00) g l–1. The concentrations of heavy metals in drinking water supplies of the Aligarh Muslim University campus were well below the guidelines for drinking water quality as prescribed by World Health Organisation (1984). It is evident from the results that the drinking water may not cause any significant health hazard to water consumers due to heavy metals but these may be hazardous if they get accumulated in the body due to continuous consumption of water.  相似文献   
212.
A method to determine the total PCB content by hydrogenolysis (hydrodechlorination and hydrogenation) of chlorinated biphenyl compounds was extended to natural particulate matrices (soil and sediment). The contaminated soil was suspended in hexane in the presence of Pd/gamma-Al2O3 in a hydrogen atmosphere then permitted to react for one hour at 65 degrees C. Dicyclohexyl, recovered in the hexane, was quantified by gas chromatography mass spectrometry. The reaction was very efficient for soil/sediment in hexane suspension and virtually complete provided that excess catalyst was added to samples that were burdened with higher PCB loadings prior to reaction otherwise some partial hydrogenation of biphenyl was also observed. The proposed method was validated with the analysis of five certified reference materials.  相似文献   
213.
Environment, Development and Sustainability - The tourism sectors consume a high amount of electrical power, which in most cases is supplied by the electrical grid and diesel generator. As a...  相似文献   
214.
Environment, Development and Sustainability - The outbreak of COVID-19 has made a global catastrophic situation that caused 1,039,406 deaths out of 35,347,404 infections, and it will also cause...  相似文献   
215.
Environmental Economics and Policy Studies - Economists have long argued over the political economy of tradable emission permits, especially the political pressure of lobby groups on international...  相似文献   
216.
A total of two hundred and forty random samples were collected equally from mutton, liver and kidney of 40 local (Jordanian) and 40 imported Australian sheep (40 each sub sample). Fresh samples were collected from 12–18 m old sheep slaughtered in abattoirs in Jordan in 2002. Besides, 40 fresh mutton samples of imported Chinese sheep were collected from different markets. Atomic absorption spectrometry (AAS) was used to estimate the lead (Pb) content of the samples. Results indicated that Australian mutton had significantly higher (p < 0.05) mean of lead pollution than that of the local and Chinese muttons. The mean concentration of lead (mg/kg) in Australian, local and Chinese muttons was 4.30, 3.15 and 2.17, respectively. The mean concentration of lead in Australian sheep liver was significantly higher (p < 0.05) than that recorded in the local sheep liver. The mean concentration of Pb in Australian and local sheep liver was 5.69 and 4.52 mg/kg, respectively. The mean concentrations of Pb in the kidney of the Australian and local sheep were not significantly different (p > 0.05). They were 4.59 and 3.87 mg/kg, respectively.On the basis of the samples lead level, 85, 92 and 87.5% of local, Australian and Chinese mutton respectively, exceeded the international safe permissible limit of 1.0 mg/kg. Furthermore, the effect of Pb on animal and human health was discussed.  相似文献   
217.
Environmental Science and Pollution Research - The effect of the flow and geometric parameters of a dimple-roughened absorber plate on the enactment of solar air collectors (SACs) with air-impinged...  相似文献   
218.
Environmental Science and Pollution Research - Long-term exposure to ionizing radiation (IR) can cause dire health consequences even less than the dose limits. Previous biomonitoring studies have...  相似文献   
219.
Environmental Science and Pollution Research - Delhi has been identified as one of the highly polluted cities in the world and recently associated with the highest population weighted PM2.5...  相似文献   
220.
The aim of this study was to assess the direct and indirect effects of shift work (SW) on the systolic blood pressure (SBP) and lipid profile of male workers. For this purpose, a cross-sectional study was conducted involving 6539 male workers of Esfahan Mobarakeh Steel Company. From all of the participants, 3065 (46.8%) were day workers and the remainder were shift workers. The results of path analysis revealed that the most effective variables on SBP were body mass index, fasting blood sugar, triglycerides and SW with a total effect of 0.241, 0.095, 0.064 and 0.056, respectively.  相似文献   
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