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1.
Huan Jing Ke Xue ; 29(6): 1737-42, 2008 Jun.
Article in Chinese | MEDLINE | ID: mdl-18763532

ABSTRACT

Cu/ZrO2/S2O8(2-)/gamma-Al2O3 solid acid catalyst was prepared by loading of (NH4)2S2O8, ZrOCl2, and Cu(NO3)2 onto gamma-Al2O3 step by step, which was obtained from calcining of pseudoboehmite. The catalytic property of Cu/ZrO2/S2O8(2-)/gamma-Al2O3 on the selective reduction of NO by C3H6 in excess oxygen was investigated. The relationship between the structure and the catalytic property of Cu/ZrO2/S2O8(2-)/gamma-Al2O3 catalyst was also explored by means of SEM, XRD, Py-IR and TPR. The experimental results of catalytic activity of the title catalyst indicated that the maximum conversion rate of NO could reach 82.9% in the absence of water and was up to 80.2% even in the presence of 10% water vapor. The results of the structural characterization toward the catalyst showed that S2O8(2-) and ZrO2 could restrain the sinteration of gamma-Al2O3 particles and the formation of CuAl2O4 spinelle, and also facilitate the formation of new acidic sites (Brönsted acid) and the enhance of the acidity on the surface of the catalyst. In addition, ZrO2 could increase the reducibility of Cu on the catalyst. Consequently, the catalytic activity and hydrothermal stability of the catalyst were improved effectively.


Subject(s)
Aluminum Oxide/chemistry , Copper/chemistry , Environmental Pollution/prevention & control , Nitrogen Oxides/chemistry , Zirconium/chemistry , Air Pollutants/analysis , Air Pollutants/chemistry , Catalysis , Copper/analysis , Nitrogen Oxides/analysis , Oxidation-Reduction
2.
Biomed Environ Sci ; 19(2): 137-42, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16827186

ABSTRACT

OBJECTIVE: To evaluate the environmental quality of Guiyu, Guangdong impacted by the electronic waste recycling industry. METHODS: The surface water, ground water and sediment samples taken separately from two sites that recycle E-wastes and other rubbish relevant to the E-waste recycling, and an agricultural area, were analyzed, and the data were used to evaluate the impact of E-waste recycling on the environmental quality of Guiyu based on environmental quality standards in China. RESULTS: The concentrations of lead and iron in the surface water samples significantly different in the three locations. The maximum value of lead in the first site was 8 times higher than the threshold of environmental quality standards for surface water. The concentration of iron in polluted sample was 22 times that of the background sample. Manganese and iron also showed a significant difference in ground water samples between the three sites. The amount of iron was 22 times that of the threshold of the quality standard for ground water, and 120 times that of the background sample. Moreover, the results of all the eight heavy metals showed significant differences among the sediment samples. The concentrations of copper, cadmium, nickel, and lead in the polluted samples were above the median benchmarks of National Oceanic and Atmospheric Administration (NOAA). The copper concentration of 2670 mg/kg was 10 times that of the median benchmark. CONCLUSION: E-waste recycling has led to the severe pollution Guiyu.


Subject(s)
Electronics , Environmental Monitoring/standards , Geologic Sediments/chemistry , Metals, Heavy/analysis , Refuse Disposal/methods , Water Pollutants, Chemical/analysis , China , Environmental Monitoring/methods , Fresh Water/chemistry , Iron/analysis , Lead/analysis , Manganese/analysis , Quality Control
3.
Biomed Environ Sci ; 18(4): 233-7, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16274104

ABSTRACT

OBJECTIVE: To provide effective environmental management for total amount control of atmospheric pollutants. METHODS: An atmospheric diffusion model of sulfur dioxide on the surface of the earth was established and tested in Shantou of Guangdong Province on the basis of an overall assessment of regional natural environment, social economic state of development, pollution sources and atmospheric environmental quality. Compared with actual monitoring results in a studied region, simulation values fell within the range of two times of error and were evenly distributed in the two sides of the monitored values. Predicted with the largest emission model method, the largest emission of sulfur dioxide would be 54,279.792 tons per year in 2010. CONCLUSION: The mathematical model established and revised on the basis of GIS is more rational and suitable for the regional characteristics of total amount control of air pollutants.


Subject(s)
Air Pollutants/analysis , Geographic Information Systems , Models, Theoretical , Sulfur Dioxide/analysis , Air Pollution/prevention & control , China , Computer Simulation , Wind
4.
J Sep Sci ; 28(1): 92-7, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15688637

ABSTRACT

A simple, rapid, reproducible, and universal non-aqueous capillary electrophoresis method has been developed for the separation and determination of three major active protoberberine alkaloids including berberine, palmatine, and jatrorrhizine within 7 min. The effects of the concentrations of acetic acid and electrolyte, the ratio of organic solvent, and the applied voltage on the separation were investigated. The optimum running buffer was composed of 50 mM ammonium acetate, 0.5% (v/v) acetic acid, and 10% (v/v) acetonitrile in methanol. The applied voltage was 18 kV. The analytes were detected by UV at 214 nm. The linearities between peak areas and the concentrations of the analytes were also investigated, and they exhibit excellent linear behavior over the concentration ranges (correlation coefficients: 0.9975-0.9986). The method was successfully applied to determine the three alkaloids in several families of herbal drugs (Rhizoma Coptidis, Cortex Berberidis, Cortex Phellodendri, Herba Chelidonii, Caulis Mahoniae) and their relevant medicinal preparations for the first time, and the recoveries of the three constituents ranged between 95.6-103.2% for berberine, 97.5-103.3% for palmatine, and 96.1 -103.6% for jatrorrhizine.


Subject(s)
Berberine Alkaloids/analysis , Berberine/analogs & derivatives , Electrophoresis, Capillary/methods , Berberine/analysis , Drugs, Chinese Herbal/analysis , Electrophoresis, Capillary/instrumentation , Electrophoresis, Capillary/statistics & numerical data , Plants, Medicinal/chemistry , Reproducibility of Results
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