Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (ACN) 60℃,24 h,using methacrylic acid (MAA),ethylene glycol dimethacrylate (EGDMA) and 2, ...Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (ACN) 60℃,24 h,using methacrylic acid (MAA),ethylene glycol dimethacrylate (EGDMA) and 2, 2-azobisiobutyronitrile (AIBN) as functional monomer,cross-linker and initiator,respectively.The recognition mechanism was elucidated by UV-vis spectra and computer modeling.Equilibrium binding experiment was employed to investigate the rebinding properties,Scatchard analysis showed that specific binding sites formed in the imprinted microspheres,and there were two kinds of binding sites,one was high binding sites,the other was low binding sites.This microspheres can be useful affinity absorbent used for organophosphorus pesticides separation and purification in food and environmental analysis.展开更多
A study on the sorption of monocrotophos and parathion methyl on Yellow River's sediments was performed. The influence of some factors, such as pH value and ionic strength, on the sorption was investigated and f...A study on the sorption of monocrotophos and parathion methyl on Yellow River's sediments was performed. The influence of some factors, such as pH value and ionic strength, on the sorption was investigated and first order kinetics mode for the sorption of monocrophos was shown. Freundlich isotherm was suggested as the most appropriate type for monocrophos and parathion methyl. But the sorption isotherms of monocrotophos and parathion methyl are also in conformity with Langmuir equation. Both partition and adsorption occur to the sorption of monocrophos to Yellow River's sediments, but partition is the predominant for that of parathion methyl.展开更多
The effects of monocrotophos and quinalphos on population and nitrogen-fixing activity of Azospirillum sp.in four agricultural soils were determined in a laboratory study.Concentrations of the two insecticides up to a...The effects of monocrotophos and quinalphos on population and nitrogen-fixing activity of Azospirillum sp.in four agricultural soils were determined in a laboratory study.Concentrations of the two insecticides up to a 5 kg ha^(-1)level were either stimulatory or innocuous to the popula- tion of Azospirillum in the soils.Four successive applications of the insecticides to soils resulted in a significant increase in the population density.Cultures of Azospirillum sp.,isolated from insecticide-treated soils,exhibited greater nitrogen-fixing activity.Three consecutive subcultur- ings of the isolates from insecticide-treated soils had no effect on their nitrogen-fixing activity.1989 Academic Press,Inc.展开更多
Uniformly imprinted polymer microspheres were prepared by precipitation polymerization in chloroform.MCP（monocrotophos）,MAA（methacrylic acid）,EGDMA（ethylene glycol dimethacrylate） and AIBN（azobisisobutyronitril...Uniformly imprinted polymer microspheres were prepared by precipitation polymerization in chloroform.MCP（monocrotophos）,MAA（methacrylic acid）,EGDMA（ethylene glycol dimethacrylate） and AIBN（azobisisobutyronitrile） were used as template,functional monomer,crosslinker and initiator,respectively.UV and IR spectra were used to demonstrate the mechanism of the interaction between MCP and MAA.It was found that one MCP was entrapped by three MAA molecules in chloroform.Langmuir model was used to fit the adsorption data,the results showed that the MCP imprinted polymer microspheres showed specific binding sites to the MCP.The data obtained in equilibrium adsorption experiments were processed by Scatchard analysis,the dissociation contents(KD1) and the apparent maximum binding capacity (Bmax1) were KD1=0.062?mmol/L,Bmax1=3.26?μmol/g for high affinity binding sites and KD2=3.03?mmol/L,Bmax2=65.70?μmol/g for low affinity binding sites,respectively.The MCP imprinted polymers have showed higher affinity to MCP than to the other organophosphorus pesticide used.So the imprinted polymers microspheres can be used for trace pesticide residue separation,enrichment and analysis.展开更多
基金support by the National Natural Science Foundation of China(No.30371218)High Technology Research and Development Program of China(863 Project No.2004AA649110)
文摘Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (ACN) 60℃,24 h,using methacrylic acid (MAA),ethylene glycol dimethacrylate (EGDMA) and 2, 2-azobisiobutyronitrile (AIBN) as functional monomer,cross-linker and initiator,respectively.The recognition mechanism was elucidated by UV-vis spectra and computer modeling.Equilibrium binding experiment was employed to investigate the rebinding properties,Scatchard analysis showed that specific binding sites formed in the imprinted microspheres,and there were two kinds of binding sites,one was high binding sites,the other was low binding sites.This microspheres can be useful affinity absorbent used for organophosphorus pesticides separation and purification in food and environmental analysis.
文摘A study on the sorption of monocrotophos and parathion methyl on Yellow River's sediments was performed. The influence of some factors, such as pH value and ionic strength, on the sorption was investigated and first order kinetics mode for the sorption of monocrophos was shown. Freundlich isotherm was suggested as the most appropriate type for monocrophos and parathion methyl. But the sorption isotherms of monocrotophos and parathion methyl are also in conformity with Langmuir equation. Both partition and adsorption occur to the sorption of monocrophos to Yellow River's sediments, but partition is the predominant for that of parathion methyl.
文摘The effects of monocrotophos and quinalphos on population and nitrogen-fixing activity of Azospirillum sp.in four agricultural soils were determined in a laboratory study.Concentrations of the two insecticides up to a 5 kg ha^(-1)level were either stimulatory or innocuous to the popula- tion of Azospirillum in the soils.Four successive applications of the insecticides to soils resulted in a significant increase in the population density.Cultures of Azospirillum sp.,isolated from insecticide-treated soils,exhibited greater nitrogen-fixing activity.Three consecutive subcultur- ings of the isolates from insecticide-treated soils had no effect on their nitrogen-fixing activity.1989 Academic Press,Inc.
文摘Uniformly imprinted polymer microspheres were prepared by precipitation polymerization in chloroform.MCP（monocrotophos）,MAA（methacrylic acid）,EGDMA（ethylene glycol dimethacrylate） and AIBN（azobisisobutyronitrile） were used as template,functional monomer,crosslinker and initiator,respectively.UV and IR spectra were used to demonstrate the mechanism of the interaction between MCP and MAA.It was found that one MCP was entrapped by three MAA molecules in chloroform.Langmuir model was used to fit the adsorption data,the results showed that the MCP imprinted polymer microspheres showed specific binding sites to the MCP.The data obtained in equilibrium adsorption experiments were processed by Scatchard analysis,the dissociation contents(KD1) and the apparent maximum binding capacity (Bmax1) were KD1=0.062?mmol/L,Bmax1=3.26?μmol/g for high affinity binding sites and KD2=3.03?mmol/L,Bmax2=65.70?μmol/g for low affinity binding sites,respectively.The MCP imprinted polymers have showed higher affinity to MCP than to the other organophosphorus pesticide used.So the imprinted polymers microspheres can be used for trace pesticide residue separation,enrichment and analysis.
