The gaseous photochemical reaction of n-pentane and sulfur dioxide was studied.A series of gaseous products such as alcohols, ketones, acids, esters and inorganic compound were identified by GC/MS and GC. According to...The gaseous photochemical reaction of n-pentane and sulfur dioxide was studied.A series of gaseous products such as alcohols, ketones, acids, esters and inorganic compound were identified by GC/MS and GC. According to the characters of the compounds and the free radical theory, the free radical mechanism of this gaseous photochemical reaction was suggested. The free radical mechanism was verified directly by means of the gaseous free radicals measured by spin trapping-ESR methods in which PBN was selected as the spintrap.展开更多
The biosorption of Pb^2+ by the organic components(exopolymer,nonliving body bacterium and living bacterium) on the dominant bacterium obtained from the surface coatings in natural waters and the effects of biosorptio...The biosorption of Pb^2+ by the organic components(exopolymer,nonliving body bacterium and living bacterium) on the dominant bacterium obtained from the surface coatings in natural waters and the effects of biosorption time,temperature and initial pH were investigated.The results showed that Pb^2+ biosorption process by the organic components above was divided into fast phase and slow phase,biosorption equilibrium time was 360,120 and 150 min respectively;the biosorption ability of exopolymer is much higher than nonliving body bacterium and living body bacterium,the maximum biosorption amount of Pb^2+ was all reached at pH=6,the effect of temperature on the biosorption ability of nonliving body bacterium and living body bacterium was negligible;both the Longmuir and Freundlish could describe the course of the biosorption of on Pb^2+ by the organic components.the biosorption ability of exopolymer is much higher than nonliving body bacterium and living body bacterium;the thermodynamics experiments also carried on when the Cd^2+ was present,the biosorption of Pb^2+ by the three organic components was also followed the Langmuir and Freundlich(equation),but the biosorption amount and the saturated biosorption amount of Pb^2+ was decreased.展开更多
The photo-generated charge property of TiO 2 nanoparticles annealed at different temperatures was studied by the field induced surface photovoltage spectrum (FISPS) technique. The powder of TiO 2 was prepared and anne...The photo-generated charge property of TiO 2 nanoparticles annealed at different temperatures was studied by the field induced surface photovoltage spectrum (FISPS) technique. The powder of TiO 2 was prepared and annealed at 400, 600 and 800 ℃, respectively. The crystalline of TiO 2 transformed from anatase to rutile with the annealing temperature increasesing. And the photo-generated charges property of TiO 2 behaves differently after it was annealed at different temperatures. When the powder was annealed at 400 ℃, the particle size is so small that the energy band can not be formed completely, so the bound exciton state was formed when it was illuminated by the proper incident light, and it inverse antisymmetrically under external field for locatization effect. While, the powder was annealed at 600 ℃, the surface phtovoltaic response presents the characteristics of homojunction for different crystalline interfaces. After being annealed at 800 ℃, the energy band was formed completely and the larger particle size(36 nm) was got. Consequently, a band for the dissociation of free exciton emerged in the band edge of the surface photovotaic response distinguished from the band-band transition, and the direction of the photovoltaic response resulted from the free excition is consistent with the external field, that is positive under positive field, and it inverse symmetrically under external field.展开更多
The effects of peptides, amino acids and organic bases as axial ligands on reaction activities in the electrocarboxylation of benzyl chloride with CO2 catalyzed by CoTPP are reported. Imidazole, peptide containing -SH...The effects of peptides, amino acids and organic bases as axial ligands on reaction activities in the electrocarboxylation of benzyl chloride with CO2 catalyzed by CoTPP are reported. Imidazole, peptide containing -SH and amino acid containing imi dazyl can enhance the catalytic activity. As an axial ligand, imidazole is the best one, it can make the current efficency of electrocarboxylation catalyzed by CoTPP rising about 23%. The effects of different amount of imidazole on CoTPP’s catalytic activities have been studied, and the cause of these effects have been explaind predrinarily.展开更多
文摘The gaseous photochemical reaction of n-pentane and sulfur dioxide was studied.A series of gaseous products such as alcohols, ketones, acids, esters and inorganic compound were identified by GC/MS and GC. According to the characters of the compounds and the free radical theory, the free radical mechanism of this gaseous photochemical reaction was suggested. The free radical mechanism was verified directly by means of the gaseous free radicals measured by spin trapping-ESR methods in which PBN was selected as the spintrap.
文摘The biosorption of Pb^2+ by the organic components(exopolymer,nonliving body bacterium and living bacterium) on the dominant bacterium obtained from the surface coatings in natural waters and the effects of biosorption time,temperature and initial pH were investigated.The results showed that Pb^2+ biosorption process by the organic components above was divided into fast phase and slow phase,biosorption equilibrium time was 360,120 and 150 min respectively;the biosorption ability of exopolymer is much higher than nonliving body bacterium and living body bacterium,the maximum biosorption amount of Pb^2+ was all reached at pH=6,the effect of temperature on the biosorption ability of nonliving body bacterium and living body bacterium was negligible;both the Longmuir and Freundlish could describe the course of the biosorption of on Pb^2+ by the organic components.the biosorption ability of exopolymer is much higher than nonliving body bacterium and living body bacterium;the thermodynamics experiments also carried on when the Cd^2+ was present,the biosorption of Pb^2+ by the three organic components was also followed the Langmuir and Freundlich(equation),but the biosorption amount and the saturated biosorption amount of Pb^2+ was decreased.
文摘The photo-generated charge property of TiO 2 nanoparticles annealed at different temperatures was studied by the field induced surface photovoltage spectrum (FISPS) technique. The powder of TiO 2 was prepared and annealed at 400, 600 and 800 ℃, respectively. The crystalline of TiO 2 transformed from anatase to rutile with the annealing temperature increasesing. And the photo-generated charges property of TiO 2 behaves differently after it was annealed at different temperatures. When the powder was annealed at 400 ℃, the particle size is so small that the energy band can not be formed completely, so the bound exciton state was formed when it was illuminated by the proper incident light, and it inverse antisymmetrically under external field for locatization effect. While, the powder was annealed at 600 ℃, the surface phtovoltaic response presents the characteristics of homojunction for different crystalline interfaces. After being annealed at 800 ℃, the energy band was formed completely and the larger particle size(36 nm) was got. Consequently, a band for the dissociation of free exciton emerged in the band edge of the surface photovotaic response distinguished from the band-band transition, and the direction of the photovoltaic response resulted from the free excition is consistent with the external field, that is positive under positive field, and it inverse symmetrically under external field.
文摘The effects of peptides, amino acids and organic bases as axial ligands on reaction activities in the electrocarboxylation of benzyl chloride with CO2 catalyzed by CoTPP are reported. Imidazole, peptide containing -SH and amino acid containing imi dazyl can enhance the catalytic activity. As an axial ligand, imidazole is the best one, it can make the current efficency of electrocarboxylation catalyzed by CoTPP rising about 23%. The effects of different amount of imidazole on CoTPP’s catalytic activities have been studied, and the cause of these effects have been explaind predrinarily.
