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621.
Microwave (MW) technology can be used to vitrify contaminated soil wastes and immobilize heavy metal ions in soils. More than 93% of the Pb(II)-contaminated soil was vitrified to a glass/ceramic formation after 30 min of MW radiation. In a 6-year study, the Pb(II) concentration of the vitrified soil in the leaching test was less than 1.0 mg/l, which is substantially below the USEPA regulatory limit of 5.0 mg/l.  相似文献   
622.
623.
This study evaluated the hydrolysis and photolysis kinetics of pyraclostrobin in an aqueous solution using ultra-high-performance liquid chromatography–photodiode array detection and identified the resulting metabolites of pyraclostrobin by hydrolysis and photolysis in paddy water using high-resolution mass spectrometry coupled with liquid chromatography. The effect of solution pH, metal ions and surfactants on the hydrolysis of pyraclostrobin was explored. The hydrolysis half-lives of pyraclostrobin were 23.1–115.5?days and were stable in buffer solution at pH 5.0. The degradation rate of pyraclostrobin in an aqueous solution under sunlight was slower than that under UV photolysis reaction. The half-lives of pyraclostrobin in a buffer solution at pH 5.0, 7.0, 9.0 and in paddy water were less than 12?h under the two light irradiation types. The metabolites of the two processes were identified and compared to further understand the mechanisms underlying hydrolysis and photolysis of pyraclostrobin in natural water. The extracted ions obtained from paddy water were automatically annotated by Compound Discoverer software with manual confirmation of their fragments. Two metabolites were detected and identified in the pyraclostrobin hydrolysis, whereas three metabolites were detected and identified in the photolysis in paddy water.  相似文献   
624.
Russian Journal of Ecology - Abstract—The study of the effect of mycorrhiza symbiosis on the transformation of carbon and nitrogen compounds in soils is important in view of the necessity to...  相似文献   
625.
Russian Journal of Ecology - A simultaneous analysis of the chronographic variation of the mandible of bank vole (Clethrionomys glareolus Shreb.) in three longitudinally distant populations that...  相似文献   
626.
Yang  W.  Deng  D. G.  Meng  X. L.  Zhang  S. 《Russian Journal of Ecology》2019,50(4):352-360
Russian Journal of Ecology - Temporal and spatial variations of phytoplankton community in Lake Erhai were investigated from May 2010 to April 2011. A total of 124 species belonging to 8 phyla and...  相似文献   
627.
Environmental Science and Pollution Research - A new set up of the integral mechanistic BIO_ALGAE model that describes the complex interactions in mixed algal-bacterial systems was developed to...  相似文献   
628.
An approach for quantifying the human health risk caused by industrial sources, which, daily or accidentally, emit dangerous pollutants able to impact on different environmental media, is introduced. The approach is performed by the HHRA-GIS tool which employs an integrated, multimedia, multi-exposure pathways and multi-receptors risk assessment model able to manage all the steps of the analysis in a georeferenced structure. Upper-bound excess lifetime cancer risk and noncarcinogenic hazards are the risk measures, the spatial distribution of which is calculated and mapped on the involved territory, once all the pathways and receptors of the study area are identified. A sensitivity analysis completes the calculations allowing to understand how risk estimates are dependent on variability in the factors contributing to risk. The last part of the paper makes use of a case study concerning a working industrial site to put in evidence in which way the designed tool can help local authorities and policy makers in managing risks and planning remedial and reduction actions. The considered geographical area is a hypothetical territory characterized by residential, agricultural and industrial zones. The presence of two sources of contamination, a municipal waste incinerator (MWI) and a contaminated site, are evaluated by the tool application. Various typologies of receptors have been taken into account, each of them characterized by different anatomical and dietary properties. The achieved results are analyzed, compared with acceptable and background values and alternatives of minor environmental impact calculated.  相似文献   
629.
Four sediment cores from the continental margin adjacent to Sydney were analyzed for 210Pb, 137Cs, trace metals (Ag, Cd, Co, Cu, Mn, Ni, Pb, Zn), iron, dry bulk density, mud and moisture content. The concentrations of trace metals in the total sediment are low at all sites, although slightly elevated concentrations of Ag, Cu, Pb and Zn are present in the fine fraction of sediment (< 62.5 microns) near a major ocean outfall. Concentrations of trace metals in the fine fraction of sediment are similar in the upper 10-15 cm, indicating strong vertical mixing of the sediments, whereas an upward coarsening grain size in the upper 1-3 cm of sediment supports physical resuspension during storms. Sediment accumulation rates on the middle shelf adjacent to Sydney were estimated from downcore profiles of 210Pb and 137Cs and range between 0.2 and 0.4 cm yr-1. Although the mass fluxes of Cu, Pb and Zn within a distance of 2 km from the outfall (up to 36.1, 30.8 and 86.2 micrograms cm-2 yr-1, respectively) are greater than 20 km north of the outfall (< 23.5 micrograms cm-2 yr-1), the low concentrations of trace metals in sediments near the outfall support an efficient dispersal of anthropogenic contaminants on this continental margin.  相似文献   
630.
The ability of Kluyveromyces marxianus IMB3 to decolorize Remazol Black-B dye was investigated. The effect of environmental conditions, such as pH and temperature were examined. No noticeable effects on decolorization were observed when pH varied from 3.0-5.5. Maximum colour removal, 98%, was achieved at 37 degrees C. Little or no colour removal was detected when K. marxianus IMB3 was incubated under anaerobic conditions. Further investigation, in which decolorization was monitored under extreme temperatures and low pH (to inhibit growth) and using ten fold dense inoculum, revealed that decolorization was due to biosorption to the yeast cells and not due to a metabolic reaction.  相似文献   
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