Rapid on-site identification of volatile organic compounds （VOCs） in ambient air is an important first step in remediation efforts. This study describes modification of a commercially available, portable GC/MS syste...Rapid on-site identification of volatile organic compounds （VOCs） in ambient air is an important first step in remediation efforts. This study describes modification of a commercially available, portable GC/MS system and development of an analysis protocol for rapid （〈 3 min） sampling and identification of VOCs typically found at contaminated sites at the low ppbv level.展开更多
Two chromium removal experiments were performed in bioreactors with and without a magnetic field under the same conditions.The release of the chromium present in the biomass was tested in two experiments one with the ...Two chromium removal experiments were performed in bioreactors with and without a magnetic field under the same conditions.The release of the chromium present in the biomass was tested in two experiments one with the initial pH of the medium and one with pH 4.0.The objective was to remove Cr(Ⅵ)and total Cr from the effluent,this was carried out by placing biological treatments of synthetic effluent contaminated with 100 mg/L of Cr(Ⅵ)in a bioreactor with neodymium magnets that applied a magnetic field(intensity85.4 mT)to the mixed culture.The removal of Cr(Ⅵ)was approximately 100.0%for the bioreactor with a magnetic field and 93,3%for the bioreactor without a magnetic field for9 hr of recirculation of the synthetic effluent by the bioreactor.The removal of total Cr was61.6%and 48.4%,with and without a magnetic field,respectively;for 24 hr.The desorption of Cr(VI)in the synthetic effluent was 0.05 mg/L,which is below the limit established by Brazilian legislation(0.1 mg/L)for the discharge of effluent containing Cr(Ⅵ)into bodies of water.The results obtained for the removal of chromium in synthetic effluent suggested that there was no significant influence on the viable cell count of the mixed culture.The desorption of Cr(Ⅵ)in synthetic effluent after bioadsorption of chromium by the mixed culture in the process of removal of chromium in bioreactors with and without a magnetic field was not significant in either of the experiments with different initial pHs.展开更多
基金supported by a grant from the Syracuse Center of Excellence
文摘Rapid on-site identification of volatile organic compounds （VOCs） in ambient air is an important first step in remediation efforts. This study describes modification of a commercially available, portable GC/MS system and development of an analysis protocol for rapid （〈 3 min） sampling and identification of VOCs typically found at contaminated sites at the low ppbv level.
基金the Federal University of Uberlandia,Faculty of Chemical Engineering,Coordination for the Improvement of Higher Education Personnel(CAPES-Brazil),Foundation for Research of the State of Minas Gerais(CRA-APQ-01407-13FAPEMIG-Brazil)National Council for Scientific and Technological Development(CNPq-Brazil)by the research support
文摘Two chromium removal experiments were performed in bioreactors with and without a magnetic field under the same conditions.The release of the chromium present in the biomass was tested in two experiments one with the initial pH of the medium and one with pH 4.0.The objective was to remove Cr(Ⅵ)and total Cr from the effluent,this was carried out by placing biological treatments of synthetic effluent contaminated with 100 mg/L of Cr(Ⅵ)in a bioreactor with neodymium magnets that applied a magnetic field(intensity85.4 mT)to the mixed culture.The removal of Cr(Ⅵ)was approximately 100.0%for the bioreactor with a magnetic field and 93,3%for the bioreactor without a magnetic field for9 hr of recirculation of the synthetic effluent by the bioreactor.The removal of total Cr was61.6%and 48.4%,with and without a magnetic field,respectively;for 24 hr.The desorption of Cr(VI)in the synthetic effluent was 0.05 mg/L,which is below the limit established by Brazilian legislation(0.1 mg/L)for the discharge of effluent containing Cr(Ⅵ)into bodies of water.The results obtained for the removal of chromium in synthetic effluent suggested that there was no significant influence on the viable cell count of the mixed culture.The desorption of Cr(Ⅵ)in synthetic effluent after bioadsorption of chromium by the mixed culture in the process of removal of chromium in bioreactors with and without a magnetic field was not significant in either of the experiments with different initial pHs.
