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101.
The effects of daily administration of hexachlorocyclohexane (HCH) for 90 days on the distribution of Cu, Zn, Fe and Mn in rat tissues were investigated. The results indicated that HCH caused a significant increase in weight of liver and spleen and decrease in the weight of kidney, heart and brain. The spleen and heart demonstrated the maximum mobilization of metals. Comparing the individual trace elements, zinc appeared to be the most active element. None of the metals assayed registered change in RBC's but there was increase in Zn, Fe and Mn concentration in plasma. 相似文献
102.
103.
Biodiversity,ecohydrology, threat status and conservation priority of the freshwater fishes of river Gomti,a tributary of river Ganga (India) 总被引:1,自引:1,他引:0
Extensive surveys were conducted to explore the diversity of fishes, distribution patterns, abundance, threat, and habitat
status in the upper, middle, and lower stretch of river Gomti, a tributary of river Ganga. Altogether 56 fish species belonging
to 20 families and 42 genera were collected from various sampling sites. Of the 56 species, five belong to the ‘endangered’
(EN) category and 11 belong to the vulnerable (VU) category. Six major categories of habitat were identified and pattern of
fish assemblage and dominant genera in each habitat studied. Considerable differences were observed in the fish species richness
and relative abundance (RA) of the species in the different sampling sites of river Gomti. Shannon–Wiener biodiversity index
has been calculated for the fishes indicating considerable variation (p < 0.05) across the river. Apart from Indian Major Carps (Labeo rohita, Catla catla, Cirrhinus mrigala), Chitala chitala, Notopterus notopterus, Ompok pabda, O. bimaculatus, Labeo bata, L. calbasu, Cirrhinus reba, Channa marulius, Bagarius bagarius, and Clupisoma garua were the important species. All the species have been reported for the first time in this river. Indiscriminate catch, poisoning,
using of fine mesh sized nets, dumping of sewage, siltation, water abstraction, changing land use pattern, decreased water
discharge, and exotic species threaten the fish diversity. Urgent need exists for taking up research on the priority fish
species and their habitat. Restoration measures have been proposed based on ecosystem scale approach for fish biodiversity
conservation. 相似文献
104.
Syed Ashfaq Nabi Ajay Gupta 《Journal of environmental science and health. Part. B》2013,48(2):239-254
Abstract Paper electrophoretic movements of a number of pesticides belonging to organophosphorus, organochlorine and pyethroid groups in various acid background electrolytes have been studied. The effect of pH and pKa of the acids on the movement of these pesticides have also been studied. It has been observed that the movement of most of the pesticides is enhanced with increase in the degree of ionisation of the acids (pKa) studied as background electrolytes. The movement also increases with increase in the pH of acids. On the basis of differential movement of pesticides towards cathode and anode, a number of separations have been achieved from binary mixtures. Monocrotophos, rogor and malathion have been determined quantitatively (28.6 ‐ 29.2 μg) in alcoholic extracts of soil samples. 相似文献
105.
Amit Kumar Gupta 《毒物与环境化学》2013,95(6):1166-1179
The effects of heavy metals, hydrocarbons, and various toxicants present in Mathura Refinery Waste Water (MRWW) on Allium cepa were examined as a model plant system. The study was based on exposure of A. cepa to different concentrations of MRWW and compared to untreated control (exposure of onion bulbs with aquaguard purified water) to determine the total protein content and activities of certain antioxidant enzymes. These enzymes were evaluated for their efficacy to serve as biomarkers of refinery waste water pollution. DNA damaging potential of MRWW was also investigated. Data demonstrated maximal enhancement in ascorbate peroxidase activity subsequent to MRWW insult, although a significant increase in activities was also noted for other enzymes in the following order: superoxide dismutase?>?glutathione-S-transferase?> catalase. This is suggestive of their potency as a biomarker of MRWW toxicity. Increase in activities of monodehydroascorbate reductase (MDHAR; 152%) and deoxyribonuclease (345%) were also found in the A. cepa system as a result of MRWW exposure. In conclusion, A. cepa system might thus serve as an appropriate tool for monitoring water pollution, especially produced by petroleum waste and heavy metals in term of induction of glutathione peroxidase, MDHAR, and deoxyribonuclease activity. 相似文献
106.
Kunwar P. Singh Shikha Gupta Premanjali Rai 《Environmental science and pollution research international》2014,21(9):6001-6015
Groundwater hydrochemistry of an urban industrial region in Indo-Gangetic plains of north India was investigated. Groundwater samples were collected both from the industrial and non-industrial areas of Kanpur. The hydrochemical data were analyzed using various water quality indices and nonparametric statistical methods. Principal components analysis (PCA) was performed to identify the factors responsible for groundwater contamination. Ensemble learning-based decision treeboost (DTB) models were constructed to develop discriminating and regression functions to differentiate the groundwater hydrochemistry of the three different areas, to identify the responsible factors, and to predict the groundwater quality using selected measured variables. The results indicated non-normal distribution and wide variability of water quality variables in all the study areas, suggesting for nonhomogenous distribution of sources in the region. PCA results showed contaminants of industrial origin dominating in the region. DBT classification model identified pH, redox potential, total-Cr, and λ 254 as the discriminating variables in water quality of the three areas with the average accuracy of 99.51 % in complete data. The regression model predicted the groundwater chemical oxygen demand values exhibiting high correlation with measured values (0.962 in training; 0.918 in test) and the respective low root mean-squared error of 2.24 and 2.01 in training and test arrays. The statistical and chemometric approaches used here suggest that groundwater hydrochemistry differs in the three areas and is dominated by different variables. The proposed methods can be used as effective tools in groundwater management. 相似文献
107.
G. Sekaran S. Karthikeyan R. Boopathy P. Maharaja V. K. Gupta C. Anandan 《Environmental science and pollution research international》2014,21(2):1489-1502
The rice-husk-based mesoporous activated carbon (MAC) used in this study was precarbonized and activated using phosphoric acid. N2 adsorption/desorption isotherm, X-ray powder diffraction, electron spin resonance, X-ray photoelectron spectroscopy and scanning electron microscopy, transmission electron microscopy, 29Si-NMR spectroscopy, and diffuse reflectance spectroscopy were used to characterize the MAC. The tannery wastewater carrying high total dissolved solids (TDS) discharged from leather industry lacks biodegradability despite the presence of dissolved protein. This paper demonstrates the application of free electron-rich MAC as heterogeneous catalyst along with Fenton reagent for the oxidation of persistence organic compounds in high TDS wastewater. The heterogeneous Fenton oxidation of the pretreated wastewater at optimum pH (3.5), H2O2 (4 mmol/L), FeSO4?7H2O (0.2 mmol/L), and time (4 h) removed chemical oxygen demand, biochemical oxygen demand, total organic carbon and dissolved protein by 86, 91, 83, and 90 %, respectively. 相似文献
108.
Rajput Alka Gupta Suneha Bansal Anuj 《Environmental science and pollution research international》2023,30(5):11272-11301
Environmental Science and Pollution Research - With the growing demand, a large amount of paddy has been harvested by growers leaving behind the stubble (left over rice straw), which is being a big... 相似文献
109.
Rai Mahendra Ingle Avinash P. Gupta Indarchand Pandit Raksha Paralikar Priti Gade Aniket Chaud Marco V. dos Santos Carolina Alves 《Environmental Chemistry Letters》2019,17(1):277-290
Environmental Chemistry Letters - Food spoilage is a major global concern due to the lack of proper packaging technology. Nanotechnology is expected to improve food packaging. Indeed, novel... 相似文献
110.
S. Anand A. Gupta S. K. Tyagi 《Mitigation and Adaptation Strategies for Global Change》2014,19(7):1077-1089
This article presents a numerical study of an Evacuated Tube Collector (ETC) based Ammonia-Water absorption refrigeration system. This system utilizes solar energy as an energy source and does not depend on conventional energy sources for its operation. The present system involves the use of hot water as an energy carrier for generator in an absorption system. The analysis system is based on computational model being developed and the thermodynamic properties of working fluids have been used from the computer code. The variation of performance parameters such as heat load of different components, exergy loss, COPCOOLING, COPHEATING and Exergy efficiency are studied with varying generator temperature. The results indicate that COPCOOLING as well COPHEATING lies in the range of 0.012–0.498 and 1.012–1.498 respectively and the values obtained are based on the maximum available solar intensity of 0.9 kW/m2 which corresponds to the collector area of about 431.7 m2 and hot water in the range of 90 °C. It is concluded that the maximum exergy loss is in generator and it is lowest in condenser. The ETC based absorption refrigeration system can be powered by renewable energy sources and does not employ ozone depleting substances. 相似文献