The micellization,intermolecular interaction and microenvironment of molecular segments in the mixed aqueous solution of PEO-PPO-PEO triblock copolymer(Pluronic F88,P84 and P123) and Surfynol 104(S104) were studie...The micellization,intermolecular interaction and microenvironment of molecular segments in the mixed aqueous solution of PEO-PPO-PEO triblock copolymer(Pluronic F88,P84 and P123) and Surfynol 104(S104) were studied by nuclear magnetic resonance method.The results showed that the addition of S104 decreased the critical micellization temperature of copolymer.When its concentration was 0.5 g/L,the most reduction was up to more than 10℃ for F88,which was most hydrophilic in the selected copolymers.This reduction was caused by the hydrophobic interaction between S104 molecules and PPO segments.The addition of S104 enhanced the hydration of PEO segments most obviously for P123.And S104 slightly increased the hydration of PPO segments before the micellization,but obviously decreased their hydration after micellization,which was attributed to the hydrophobic interaction mentioned above and temperature rising.This effect was most observable for F88.展开更多
Surfactants, such as non-ionic Surfynol485(ethoxylated 2,4,7,9-tetramethyl-5-decyne-4,7-diol), have been applied to accelerate removal of polycyclic aromatic hydrocarbons from soil. This study investigated the dissipa...Surfactants, such as non-ionic Surfynol485(ethoxylated 2,4,7,9-tetramethyl-5-decyne-4,7-diol), have been applied to accelerate removal of polycyclic aromatic hydrocarbons from soil. This study investigated the dissipation of anthracene, and carbon(C) and nitrogen(N) mineralization in soil amended with non-ionic Surfynol485 at different rates. Soil samples of a Typic Fragiudept taken from Otumba, Mexico were spiked with anthracene at a final concentration of 520 mg kg-1dry soil using acetone as solvent, amended with 0.0, 24.9, 49.8 or 124.4 g kg-1soil of the surfactant and incubated in the laboratory. The soil not amended with anthracene,acetone and the surfactant was used as a control. Dynamics of C and N and the concentration of anthracene were monitored for 56 d. After 56 d of incubation, 38% of the anthracene was removed from the unamended soil, and 47%, 55% and 66% of the anthracene were removed when 24.9, 49.8 and 124.4 g kg-1of the surfactant were applied, respectively. Application of acetone, anthracene or surfactant increased the emission of CO2, but decreased the mineral N compared to the unamended control. Applying the surfactant to the acetone or anthracene-amended soil reduced emission of CO2, but increased the mineral N at the lower application rates of the surfactant. It was found that the application of the non-ionic surfactant increased the bioavailability of anthracene and thus its removal from soil, increased C mineralization, but decreased N mineralization. Consequently, the application of non-ionic surfactant could be easily used to accelerate the removal of pollutants from hydrocarbon-contaminated soils, but mineral N in the soil would decrease, which might inhibit plant growth.展开更多
基金Supported by the National Natural Science Foundation of China (No.20676137,20876158)The GF Fundamental Research Program (No.A1320070102)
文摘The micellization,intermolecular interaction and microenvironment of molecular segments in the mixed aqueous solution of PEO-PPO-PEO triblock copolymer(Pluronic F88,P84 and P123) and Surfynol 104(S104) were studied by nuclear magnetic resonance method.The results showed that the addition of S104 decreased the critical micellization temperature of copolymer.When its concentration was 0.5 g/L,the most reduction was up to more than 10℃ for F88,which was most hydrophilic in the selected copolymers.This reduction was caused by the hydrophobic interaction between S104 molecules and PPO segments.The addition of S104 enhanced the hydration of PEO segments most obviously for P123.And S104 slightly increased the hydration of PPO segments before the micellization,but obviously decreased their hydration after micellization,which was attributed to the hydrophobic interaction mentioned above and temperature rising.This effect was most observable for F88.
基金Supported by Cinvestav,M'exico,Consejo Nacional de Ciencia y Tecnología(CONACy T),Mexico and Sistema Nacional de Investigadores(SNI),Mexico
文摘Surfactants, such as non-ionic Surfynol485(ethoxylated 2,4,7,9-tetramethyl-5-decyne-4,7-diol), have been applied to accelerate removal of polycyclic aromatic hydrocarbons from soil. This study investigated the dissipation of anthracene, and carbon(C) and nitrogen(N) mineralization in soil amended with non-ionic Surfynol485 at different rates. Soil samples of a Typic Fragiudept taken from Otumba, Mexico were spiked with anthracene at a final concentration of 520 mg kg-1dry soil using acetone as solvent, amended with 0.0, 24.9, 49.8 or 124.4 g kg-1soil of the surfactant and incubated in the laboratory. The soil not amended with anthracene,acetone and the surfactant was used as a control. Dynamics of C and N and the concentration of anthracene were monitored for 56 d. After 56 d of incubation, 38% of the anthracene was removed from the unamended soil, and 47%, 55% and 66% of the anthracene were removed when 24.9, 49.8 and 124.4 g kg-1of the surfactant were applied, respectively. Application of acetone, anthracene or surfactant increased the emission of CO2, but decreased the mineral N compared to the unamended control. Applying the surfactant to the acetone or anthracene-amended soil reduced emission of CO2, but increased the mineral N at the lower application rates of the surfactant. It was found that the application of the non-ionic surfactant increased the bioavailability of anthracene and thus its removal from soil, increased C mineralization, but decreased N mineralization. Consequently, the application of non-ionic surfactant could be easily used to accelerate the removal of pollutants from hydrocarbon-contaminated soils, but mineral N in the soil would decrease, which might inhibit plant growth.
