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111.
The effect of calcium and magnesium either singly or in combination on accumulation of cadmium and copper in Labeo rohita (rohu) and Catla catla (catla) was investigated in this study under laboratory conditions. The investigation showed that copper accumulation in rohu exposed to 0.25 mg L?1 of copper for 14 days reduced from 31.0 ± 0.4 mg kg?1 at no calcium/magnesium treatment to 3.5 ± 0.2 and 2.2 ± 0.1 mg kg?1, respectively, at 75 mg L?1 calcium or magnesium treatment. The copper level in catla exposed to 0.20 mg L?1 of copper for 14 days reduced from 5.7 ± 0.1 mg kg?1 at no calcium/magnesium treatment to 3.4 ± 0.2 and 3.3 ± 0.1 mg kg?1, respectively, at 300 mg L?1 calcium or magnesium treatment. The cadmium accumulation in rohu exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 1.7 ± 0.1 mg kg?1 at no magnesium treatment to 1.4 ± 0.1 mg kg?1 at 120 mg L?1 magnesium treatment. The cadmium accumulation in catla exposed to 0.20 mg L?1 of cadmium for 14 days reduced from 0.8 ± 0.2 mg kg?1 at no magnesium treatment to 0.6 ± 0.2 mg kg?1 at 80 mg L?1 magnesium treatment. Copper and cadmium treatments also reduced some essential microelements of rohu and catla. Both the fishes restored these elements at different levels of calcium and magnesium.  相似文献   
112.
Environmental Chemistry Letters - Diminishing petroleum reserves, increasing carbon emissions, and the growing demand for fuels are calling for alternative fuels. Global diesel consumption...  相似文献   
113.
Water availability in arid regions is both sporadic and highly variable in quantity. If the water quality shows large variations of salinity and concentration of other chemical constituents with depth and time span, it has considerable effect on the entire hydrological set up of the area. In the Saidabad tahsil area, the deep aquifers that supply water to borewells in the alluvial plain of the Mathura region, Uttar Pradesh, have higher salinity than those of the dugwells from the shallow aquifers. The excessive drilling of tubewells and high yield tubewells are resulting in deterioration of water quality of the shallow aquifers. On the contrary, the chemical constituents such as, Na+, K +, Cl -, andHCO 3 - show higher concentration in shallow aquifers than deep aquifers. A study carried out to monitor water quality in this region reveals that the groundwater quality varies with depth and time span in shallow and deep aquifers. Factors controlling variations in salinity and concentration of chemical constituents of the water in the two types of aquifers are discussed. The relative merits of the shallow water for potability are pointed out with respect to salinity concentrations and public health.  相似文献   
114.
Supervised field trials were conducted at four different agro-climatic locations of India to evaluate the dissipation pattern and risk assessment of spiromesifen on tomato. Spiromesifen 240 SC was sprayed on tomato at 150 and 300 g a.i.?ha?1. Samples of tomato fruits were drawn at 0, 1, 3, 5, 7, 10 and 15 days after treatment and soil at 15 days after treatment. Quantification of residues was done on gas chromatograph–mass spectrophotometer in selective ion monitoring mode in the mass range of 271–274 (m/z). The limit of quantification of the method was found to be 0.05 mg kg?1, while the limit of determination was 0.015 mg kg?1. Residues were found below the LOQ of 0.05 mg kg?1 in 10 days at both the doses of application at all the locations. Spiromesifen dissipated with a half-life of 0.93–1.38 days at the recommended rate of application and 1.04–1.34 days at the double the rate of application. Residues of spiromesifen in soil were detectable level (<0.05 mg kg?1) after 15 days of treatment. A preharvest interval (PHI) of 1 day has been recommended on tomato on the basis of data generated under All India Network Project on Pesticide Residues. Spiromesifen 240 SC has been registered for its use on tomato by Central Insecticide Board and Registration Committee, Ministry of Agriculture, Government of India. The maximum residue limit (MRL) of spiromesifen on tomato has been fixed by Food Safety Standard Authority of India, Ministry of Health and Family Welfare, Government of India as 0.3 μg/g after its risk assessment.  相似文献   
115.
Cattle grazing nearby coal-fired power stations are exposed to fly ash. The present investigation aims to assess the environmental and health impacts of fly ash containing mercury emitted from thermal power plant. The health effect of fly ash were studied using 20 lactating cattle reared within a 5-km radius of s thermal power plant for the possible effect of fly ash such as the alterations in hematological and biochemical parameters of blood, milk, and urine. Results indicated that the hemoglobin levels (6.65?±?0.40?g/dl) were significantly reduced in all the exposed animals. Biochemical parameters viz., blood urea nitrogen (27.35?±?1.19?mg/dl), serum glutamate oxaloacetate transaminase (43.39?±?3.08?IU/l), albumin, and creatinine were found to be increased, whereas serum glutamate pyruvic transaminase (29.26?±?2.02) and Ca2+ were observed to be statistically insignificant in exposed animals. Mercury concentrations estimated in the blood, milk, and urine of exposed (n?=?20) and control (n?=?20) animals were 7.41?±?0.86, 4.75?±?0.57, 2.08?±?0.18, and 1.05?±?0.07, 0.54?±?0.03, 0.20?±?0.02?μg/kg, respectively. The significant increase (P?<?0.01) in the levels of mercury in blood, milk, and urine of exposed animals in comparison to control indicated that the alterations of biochemical parameters in exposed cattle could be due to their long term exposure to fly ash mercury which may have direct or indirect impact on human populations via food chain.  相似文献   
116.
117.
This study investigated dioxins and dioxin-like polychlorinated biphenyls in gasses emitted from waste incinerators and thermal processes in central and western parts of India. The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) ranged from 0.0070 to 26.8140 ng toxicity equivalent (TEQ)/Nm3, and those of dioxin-like polychlorinated biphenyls (PCBs) ranged from 0.0001?×?10?1 to 0.0295 ng TEQ/Nm3. The characteristics of mean PCDD/F I-TEQ concentration and congener profiles were studied over all the samples of air. In particular, a pattern consisting of a low proportion of dioxin-like PCBs and high proportion of PCDDs/DFs was common for all the samples from incinerators and high-temperature processes.  相似文献   
118.
Elasticity of substitution is traditionally estimated while ignoring technical and allocative inefficiencies, which could bias the estimates. We estimate elasticity of substitution for Chinese energy-intensive sectors by incorporating these inefficiencies. The results show most of the sectors are low substitutes between input factors and stress important differences among energy-intensive sectors. Concerning the cross-price elasticity for energy, with respect to capital (labor), the sectors are mainly characterized by weak substitutability or complementary. These imply the production structure is quite rigid and capital cannot be so readily used as a substitute for energy.  相似文献   
119.
The results of a pilot study that was conducted to determine the total nitrogen removal by the reverse osmosis process are presented. The organic nitrogen removal rates are compared with removals observed from three full-scale reverse osmosis facilities and four pilot studies. The results of this analysis suggest that organic nitrogen removal is variable and that reverse osmosis may not consistently produce total nitrogen levels less than 1.0 mg/L without additional treatment. Three hypotheses to explain the variability in organic nitrogen removal in the different data sets are presented.  相似文献   
120.
Sources of submicron aerosol during fog-dominated wintertime at Kanpur   总被引:1,自引:0,他引:1  
The main objective of this atmospheric study was to determine the major sources of PM1 (particles having aerodynamic diameter <1.0 μm) within and near the city of Kanpur, in the Indo-Gangetic Plain. Day and night, 10 h long each, filter-based aerosol samples were collected for 4 months (November 2009 to February 2010) throughout the winter season. These samples were subjected to gravimetric and quantitative chemical analyses for determining water-soluble ions (NH4 +, F?, Cl?, NO3 ?, and SO4 2?) using an ion chromatograph and trace elements using an inductively coupled plasma–optical emission spectrometer. The mean PM1 mass concentrations were recorded as 114?±?71 μg/m3 (day) and 143?±?86 μg/m3 (night), respectively. A significantly higher diurnal contribution of ions (NH4 +, F?, Cl?, NO3 ?, and SO4 2?) in PM1 mass was observed during the fog-affected days and nights throughout the winter season, for which the average values were recorded as 38.09?±?13.39 % (day) and 34.98?±?12.59 % (night), respectively, of the total PM1 mass. This chemical dataset was then used in a source-receptor model, UNMIX, and the model results are described in detail. UNMIX provided a maximum number of five source factors, including crustal material, composite vehicle, secondary aerosol, coal combustion, and iron/steel production and metallurgical industries, as the dominant air pollution sources for this study.  相似文献   
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