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Environmental Science and Pollution Research - The estrogenic property of bisphenol A (BPA) leads to potential adverse health and ecological effects. A simple, selective, and cost-effective sensor...  相似文献   
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This paper presents the results of the lidar experiments that have been performed during January 1989 through August 1990 to study the aerosol vertical distributions in the nocturnal atmosphere and their comparison with near-simultaneous aerological soundings for environmental monitoring. During the study period, the aerosol distributions showed significant stratified aerosol layer structures in the lower atmosphere throughout the south-west monsoon season (June-September), while these structures appear to be either erratic or absent during remaining months of the year. In addition, the aerosols present in the lowest air layers up to 200 m are found to contribute significantly (about 40%) to the aerosol loading in the nocturnal boundary layer at the lidar site. The pre-monsoon to winter ratio of mixing depth and ventilation coefficient were found to be 1.11 and 1.62, respectively. Thus the height of the mixed layer (around 350 m) and the associated ventilation coefficients suggest that early winter evenings tend to have higher pollution potential at the experimental site. The results indicate that the lidar technique has the potential to yield good information on the structure of the nocturnal atmosphere which is found to be influenced by the atmospheric stability conditions as revealed by aerological observations.  相似文献   
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Virulence expression of Salmonella enterica serovar Typhimurium under iron limited condition was measured by beta-galactosidase (beta-gal) assay using a hilA-lacZY fusion strain and calculated as Miller units. hilA-lacZY beta-galactosidase assays were performed in brain heart infusion (BHI) and minimal media (M9), after iron chelation with 2, 2-dipridyl and iron-supplementation respectively. Before performing virulence assays, concentrations of iron in the media were estimated using ferrozine. Iron content was found to be more in BHI (42.6 microg dL(-1)) as compared to M9 (10.03 microg dL(-1)). beta-gal activity of Salmonella Typhimurium in BHI was generally less than that observed in M9. After exposure to various combinations of iron chelator in BHI, hilA-lacZY activity only increased at the highest concentration of chelator (2001 microM) but decreased in M9 media for all iron concentrations when compared to controls with no iron amendment. These results indicate that iron availability may influence S. Typhimurium hilA expression.  相似文献   
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This study explores power law relationships to estimate water flow velocity as a function of discharge and drainage area across river networks. We test the model using empirical data from 214 United States (U.S.) Geological Survey gauging stations distributed over the state of Iowa in the U.S. The empirical data are the measurements of the mean cross‐sectional velocity and concurrent discharge. The data are used to estimate parameters for a state‐wide model and to test for spatial variability for 15 large river basins contained within the state. Spatial differences among the basins are small but some parameters significantly differ from the state‐wide model. Using individual station data, the authors also explore a simpler power law model that disregards dependence on the drainage area. Overall, the study shows that including drainage area improves the model. Our study provides parameter values that can be directly incorporated into a regional scale routing model, and provides a framework for developing flow velocity models for hydraulically similar rivers in the U.S. and the world.  相似文献   
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Environmental Science and Pollution Research - The huge demand and consumption of DOX, its incomplete metabolism, and complex behavior in atmosphere are causing a great ecological issue, which...  相似文献   
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The concentrations of suspended particulate matter in the air of the Orissa Sand Complex had an average value of 128 ± 10 µg m?3 in residential areas and 170 ± 8 µg m?3 in mining areas. PM10 levels in residential areas were found to have an average of 35 ± 10 µg m?3, in mining areas 45 ± 10 µg m?3. The distribution of some elements is also discussed here. Inhalation doses were observed to be higher in summer than in winter and the rainy season. The highest dose rate was for the age group of 1 year, and health risks were found to be highest for the same. For adults, inhalation dose and health risk are 1.3 times higher in mining than in residential areas.  相似文献   
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Over the past few decades, the industry developed an increasing interest in using renewable, bio-based thermosetting polymers as matrix systems for composites and coating systems. In the present paper an acrylated epoxidized linseed oil (AELO) was synthesized from epoxidized linseed oil (ELO) through ring opening of the oxirane group using acrylic acid as the ring opening agent. The synthesized AELO was mixed with three different photoinitiators and cured under monochromatic conditions (???=?365?nm) at different light intensities and at different temperatures. The concentration of the initiators was aligned that all initiators absorb at 365?nm the same amount of light. The evolution of cure was monitored by using real-time infrared spectroscopy with a heated attenuated total reflection unit. The decrease of absorption in the measured spectra at 1,406?cm?1 was used to calculate the conversion of acrylic double bonds with increasing time of UV light exposure to get information about the cure kinetics for each AELO mixture at different light intensities and different temperatures. Wood substrates were coated in a preliminary work with the AELO mixtures and after UV-curing some technological coating properties like gloss, scratch resistance, adhesion, and solvent resistance were tested. In combination with the information about the cure kinetics in the present work the coating properties were correlated with the cure evolution and the final degree of double bond conversion. The found correlation can be used in the future to find optimized coating conditions for the AELO mixtures on wood substrates.  相似文献   
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The study on the removal of NOx from simulated flue gas has been carded out in a lab-scale bubbling reactor using acidic solutions of sodium chlorite. Experiments were performed at various pH values and inlet NO concentrations in the absence or presence of SO2 gas at 45℃. The effect of SO2 on NO oxidation and NO2 absorption was critically examined. The oxidative ability of sodium chlorite was investigated at different pH values and it was found to be a better oxidant at a pH less than 4. In acidic medium, sodium chlorite decomposed into C102 gas, which is believed to participate in NO oxidation as well as in NO2 absorption. A plausible NOx removal mechanism using acidic sodium chlorite solution has been postulated. A maximum NOx removal efficiency of about 81% has been achieved.  相似文献   
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