In Kazakhstan, there are obsolete pesticides which should be buried in special dedicated and prepared burial sites or neutralized for minimization of dangerous genetic and ecological risks. The work in two years was i...In Kazakhstan, there are obsolete pesticides which should be buried in special dedicated and prepared burial sites or neutralized for minimization of dangerous genetic and ecological risks. The work in two years was identifying the obsolete pesticides in 91 the former warehouses of chemical plant protection products. In two regions （Almaty and Akmola regions） of Kazakhstan, the total amount of 388.6 tones of obsolete pesticides and unidentified stockpile material was observed, along with 513 pesticide containers. Results of the study have shown that soil around storehouses polluted by organochlorine pesticides residues in soil included metabolites of DDT （p, p＇-dichlorodiphenyltrichloroethane） and HCH （hexachlorocyclohexane）. The strategy was to identify pesticide-tolerant plant genotypes which can be used for phytoremediation of pesticide-contaminated soils in Almaty regions of Kazakhstan. The results have shown that selected wild species plants demonstrated ability to phytoaccumulation of organochlorine metabolites and reduce pesticide concentrations in soil （control without plant）. It was shown that accumulation of pesticides depended on the species of plants, plant biomass and pesticide concentrations in soil. The use of mineral fertilizers resulted in stimulation of growth and biomass accumulation followed by an increasing phytoextraction.展开更多
Based on the layer-by-layer self-assembly of positively charged cetyltrimethylammonium bromide （CTAB） wrapped gold na- norods （AuNRs） and negatively charged superoxide dismutase （SOD） from their aqueous solution...Based on the layer-by-layer self-assembly of positively charged cetyltrimethylammonium bromide （CTAB） wrapped gold na- norods （AuNRs） and negatively charged superoxide dismutase （SOD） from their aqueous solutions on cysteine modified gold electrode （Cys/Au）, a third generation electrochemical biosensor （（SOD/AuNRs）2/Cys/Au） for superoxide anion （02＂-） was developed. The two layers assembly of SOD/AuNRs can significantly enhance the direct electron transfer between SOD and the electrode. The functional enzymatic activities of the SOD offer an electrochemical approach to the determination of 02＂-. In the reductive regions, the proposed sensor exhibits excellent analytical performances, such as wide linear range （200 nM to 0.2 mM O2-）, low detection limit （100 nM O2-）, high sensitivity （22.11 nA cm-2 μM-1）, short response time （less than 5 s）, good stability and reproducibility, while no obvious interferences are caused by commonly met interfering species including hydrogen peroxide （H202）, uric acid （UA） and ascorbic acid （AA）.展开更多
文摘In Kazakhstan, there are obsolete pesticides which should be buried in special dedicated and prepared burial sites or neutralized for minimization of dangerous genetic and ecological risks. The work in two years was identifying the obsolete pesticides in 91 the former warehouses of chemical plant protection products. In two regions （Almaty and Akmola regions） of Kazakhstan, the total amount of 388.6 tones of obsolete pesticides and unidentified stockpile material was observed, along with 513 pesticide containers. Results of the study have shown that soil around storehouses polluted by organochlorine pesticides residues in soil included metabolites of DDT （p, p＇-dichlorodiphenyltrichloroethane） and HCH （hexachlorocyclohexane）. The strategy was to identify pesticide-tolerant plant genotypes which can be used for phytoremediation of pesticide-contaminated soils in Almaty regions of Kazakhstan. The results have shown that selected wild species plants demonstrated ability to phytoaccumulation of organochlorine metabolites and reduce pesticide concentrations in soil （control without plant）. It was shown that accumulation of pesticides depended on the species of plants, plant biomass and pesticide concentrations in soil. The use of mineral fertilizers resulted in stimulation of growth and biomass accumulation followed by an increasing phytoextraction.
基金supported by the National Natural Science Foundation of China (20805013, 20905024&21075031)the National Basic Research Program of China (2009CB421601 & 2011CB911002)the Natural Science Foundation of Hunan Province (09JJ4006 & 09JJ4007)
文摘Based on the layer-by-layer self-assembly of positively charged cetyltrimethylammonium bromide （CTAB） wrapped gold na- norods （AuNRs） and negatively charged superoxide dismutase （SOD） from their aqueous solutions on cysteine modified gold electrode （Cys/Au）, a third generation electrochemical biosensor （（SOD/AuNRs）2/Cys/Au） for superoxide anion （02＂-） was developed. The two layers assembly of SOD/AuNRs can significantly enhance the direct electron transfer between SOD and the electrode. The functional enzymatic activities of the SOD offer an electrochemical approach to the determination of 02＂-. In the reductive regions, the proposed sensor exhibits excellent analytical performances, such as wide linear range （200 nM to 0.2 mM O2-）, low detection limit （100 nM O2-）, high sensitivity （22.11 nA cm-2 μM-1）, short response time （less than 5 s）, good stability and reproducibility, while no obvious interferences are caused by commonly met interfering species including hydrogen peroxide （H202）, uric acid （UA） and ascorbic acid （AA）.
