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21.
The objective of this study was to determine the blood lead level (BLL) of children aged under 5 living in western Uttar Pradesh, India. A total of 100 blood samples, 100 drinking water samples, and 21 vegetable samples were assessed for lead (Pb) contamination. BLL was observed in the range of 3–11.58?µg?dL?1 with a maximal level of 11.58?±?0.05?µg?dL?1 in Kazipur village. Lead in water samples was detected in the range of 0.006–0.095?ppm and identified at upto 9.5-fold higher than the stated permissible limit. A significant positive correlation (+0.679) was obtained between BLL and water Pb levels. All vegetable samples were also contaminated with Pb upto 12-fold higher than the permissible limit of 2.5?µg?g?1 of Prevention of Food Adulteration Act (PFA) 1954. Untreated industrial effluents were identified as the responsible factors for Pb occurrence in the study area. The presence of lead may be associated with the increased antisocial activities of children living in western Uttar Pradesh. Children with elevated BLL had poorer nutritional status than those with background Pb levels. There is an urgent need for a national campaign to monitor the BLL of children in India. 相似文献
22.
This is the first report of bisphenol A release from polycarbonate during biodegradation by marine microorganisms. Bisphenol
A is a monomer in polycarbonate and an endocrine disruptor toxic for marine organisms. Biodegradation of polycarbonate is
poorly documented. Here, we have tested the possible release of bisphenol A and metabolites during biodegradation of polycarbonate
by marine microorganisms. Polycarbonate degradation was carried out in vitro using a mixed marine microbial consortium isolated
from the Bay of Bengal, India, 1 year under controlled laboratory conditions. The degradation was monitored by elemental analysis
(EA), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), and gas chromatography—mass
spectrometry (GC–MS). The organic soluble metabolites were analyzed by high-performance liquid chromatography (HPLC). We found
that bisphenol A was released. The amount of bisphenol A released during 1 year is higher than the half-maximal effective
concentration (EC50) values reported for marine organisms. We also identified the following bisphenol A metabolites: 4-hydroxyacetophenone, 4-hydroxybenzaldehyde,
and 4-hydroxybenzoic acid. Polycarbonate biodegradation was evidenced by gravimetric weight loss and Fourier transform infrared
spectroscopy. The reduction of methyl and carbonyl indices suggests oxidation and hydrolysis of the polymer, respectively.
2D NMR showed an aromatic C–C cleavage. 相似文献
23.
Li Ronghua Zhang Zengqiang Awasthi Mukesh Kumar Wang Hailong 《Environmental science and pollution research international》2020,27(35):43425-43427
Environmental Science and Pollution Research - 相似文献
24.
Heavy metal pollution of water resources can be apprehended in East Singhbhum region which is a highly mineralised zone with
extensive mining of copper, uranium and other minerals. Ten groundwater samples were collected from each site and the heavy
metal analysis was done by atomic absorption spectrophotometer. Analysis of the results of the study reveals that the concentration
of iron, manganese, zinc, lead, copper and nickel in groundwater of Bagjata mining area ranged 0.06–5.3 mg l − 1, 0.01–1.3 mg l − 1, 0.02–8.2 mg l − 1, 1.4–28.4 μg l − 1, 0.78–20.0 μg l − 1 and 1.05–20.1 μg l − 1, respectively. In case of Banduhurang mining area, the range was 0.04–2.93 mg l − 1, 0.02–1.1 mg l − 1, 0.01–4.68 mg l − 1, 1.04–33.21 μg l − 1, 1.24–18.7 μg l − 1 and 1.06–14.58 μg l − 1, respectively. The heavy metals were found to be below the drinking water standards (IS:10500 1993) except iron (0.3 mg l − 1) and manganese (0.1 mg l − 1). The hazard quotients of the heavy metals for drinking water were below 1 posing no threat due to intake of water to the
people for both the areas. 相似文献
25.
Aatmeeyata D.S. Kaul Mukesh Sharma 《Atmospheric environment (Oxford, England : 1994)》2009,43(35):5691-5697
This study aimed to understand the non-exhaust (NE) emission of particles from wear of summer tire and concrete pavement, especially for two wheelers and small cars. A fully enclosed laboratory-scale model was fabricated to simulate road tire interaction with a facility to collect particles in different sizes. A road was cast using the M-45 concrete mixture and the centrifugal casting method. It was observed that emission of large particle non exhaust emission (LPNE) as well as PM10 and PM2.5 increased with increasing load. The LPNE was 3.5 mg tire−1 km−1 for a two wheeler and 6.4 mg tire−1 km−1 for a small car. The LPNE can lead to water pollution through water run-off from the roads. The contribution of the PM10 and PM2.5 was smaller compared to the LPNE particles (less than 0.1%). About 32 percent of particle mass of PM10 was present below 1 μm. The number as well as mass size distribution for PM10 was observed to be bi-modal with peaks at 0.3 μm and 4–5 μm. The NE emissions did not show any significant trend with change in tire pressure. 相似文献
26.
Shakti Singh Mukesh Singh S. C. Kaushik 《International Journal of Green Energy》2016,13(15):1564-1578
Solar and wind are inexhaustible, abundant, environmentally friendly and freely available renewable energy sources. Integration of these two sources has always been a complex optimization problem which requires efficient planning, designing and control strategies. Many researchers have designed cost effective and efficient hybrid solar-wind energy systems by using various available software tools and optimization algorithms. With the advancement in artificial intelligence methods, various new optimization techniques have been developed in the last few decades. This paper presents state of the art optimization methods applied to hybrid renewable based energy systems. A brief introduction of each technique is presented along with papers published in different reputed journals. This article also reviews different power management, control strategies and multi-objective optimization methods used for hybrid wind-solar systems. A case study is presented to demonstrate the efficacy of some of the algorithms. 相似文献
27.
Introduction
The kinetics of the transformation of ammonia and acid gases into components of PM2.5 has been examined. The interactions of existing aerosols and meteorology with the transformation mechanism have also been investigated. The specific objective was to discern the kinetics for the gas-to-particle conversion processes where the reactions of NH3 with H2SO4, HNO3, and HCl take place to form (NH4)2SO4, NH4NO3, and NH4Cl, respectively, in PM2.5. 相似文献28.
N. A. Shakil Manish K. Singh Jitendra Kumar M. Sathiyendiran Gaurav Kumar Mukesh K. Singh 《Journal of environmental science and health. Part. B》2013,48(6):524-530
Microwave irradiation (MWI) of acetophenones and substituted benzaldehydes in water resulted in a “green-chemistry” procedure for the preparation of chalcones (1-14), through base catalyzed Claisen-Schmidt condensation reaction, in good yields. Further 3,5-diaryl-6-carbethoxy-2-cyclohexen-1-ones (1a-14a) were prepared through base catalyzed cyclocondensation of above chalcones with ethylacetoacetate using MWI as the energy source and silica as support. Out of fourteen cyclohexenones, ten (1a, 4a, 5a, 6a, 7a, 9a, 10a, 11a, 12a and 13a) are reported for the first time in literature. The synthesized compounds were characterized using various spectroscopic techniques, viz. (1H NMR and IR) and screened for their antifungal activity in vitro against Sclerotium rolfsii and Rhizoctonia solani by poisoned food technique. The compounds tested were found to be active against R. solani whereas against S. rolfsii, moderate activity was observed, as evident from LC50 values. The most potent compounds against R. solani were 1-(4-Fluoro-phenyl)-3-phenyl-propenone (13) and 1,3-Diphenyl-propenone (14) having LC50 values of 2.36 and 2.49 mgL? 1 respectively (LC50 of Hexaconazole = 1.12 mgL? 1) and against S. rolfsii 3-(4-Fluoro-phenyl)-5-(3-nitro-phenyl)-6-carbethoxy-2-cyclohexen-1-one (12a) was most active having LC50 value of 285 mgL? 1compared to Hexaconazole (LC50 = 1.27 mgL? 1). 相似文献
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30.
Satya P. Mohapatra Mukesh Kumar Vijay T. Gajbhiye Narendra P. Agnihotri 《Environmental monitoring and assessment》1995,35(2):155-164
Residues of several organochlorine insecticides were monitored in the ground water from a rural area near Farrukhabad in the vicinity of the Ganga River in northern India for one year (1991–1992). Almost all the samples were found to be contaminated with residues of Hexachlorocyclohexane (HCH) and Dichloro-diphenyl-trichloroethane (DDT). Residues of Aldrin, endosulfan and heptachlor were also detected in a large number of samples. The concentrations of aldrin residues greatly exceeded the WHO guideline value for drinking water, concentrations of heptachlor and DDT residues also occasionally exceeded the specified limits. Migration of pollutants through ground water recharge with polluted Ganga River water and monsoon rains carrying undergraded residues downwards from the soil surface are throught to be important sources of insecticide contamination of ground water in the region. 相似文献