Soil column liquid chromatography (SCLC) was developed to determine soil organic carbon adsorption coefficients (E-oc) for chemicals. The uptake by soil of pesticides from water can be conveniently calculated from the...Soil column liquid chromatography (SCLC) was developed to determine soil organic carbon adsorption coefficients (E-oc) for chemicals. The uptake by soil of pesticides from water can be conveniently calculated from the related breakthrough curves (BTC). The nine pesticides chosen for determination in this study are soluble ones, with their water solubility ranging from 62 mg/L to Z mg/L. In comparing with existing methods of K-oc, SCLC possesses rapid, online and accurate characteristics.展开更多
Sorption isotherms different fractions from two of galaxolide （HHCB） of sediments with different mineral and organic carbon contents were determined to compare HHCB sorption behavior and contribution to the total so...Sorption isotherms different fractions from two of galaxolide （HHCB） of sediments with different mineral and organic carbon contents were determined to compare HHCB sorption behavior and contribution to the total sorption. The HHCB sorption isotherms that used the batch equilibration method were studied on different sediments of different fractions. The sorption isotherms of 600℃ heating fractions were detailed using the linear model, while the other fractions were nonlinear and fitted well with the Freundlich carbon （DOC） removed, model. The dissolved organic NaOH extracted, and 375℃ heating fractions showed more nonlinear sorption than the original sediments, which suggested more heterogeneous sorption sites in these fractions. Compared to the original sediments, the 375~C heating fractions had higher carbon- normalized distribution coefficient （Koc） values, indicating a higher sorption affinity for HHCB. Among the different sediment fractions, the contribution of the 600℃ heating fractions to the overall sorption were the lowest （ 〈 20%）, while the 375℃ heating fractions were the highest （up to 85%）.展开更多
基金Bayer AG and Chinese Academy of Agricultural Sciences for kindly supplying the pesticides.
文摘Soil column liquid chromatography (SCLC) was developed to determine soil organic carbon adsorption coefficients (E-oc) for chemicals. The uptake by soil of pesticides from water can be conveniently calculated from the related breakthrough curves (BTC). The nine pesticides chosen for determination in this study are soluble ones, with their water solubility ranging from 62 mg/L to Z mg/L. In comparing with existing methods of K-oc, SCLC possesses rapid, online and accurate characteristics.
文摘Sorption isotherms different fractions from two of galaxolide （HHCB） of sediments with different mineral and organic carbon contents were determined to compare HHCB sorption behavior and contribution to the total sorption. The HHCB sorption isotherms that used the batch equilibration method were studied on different sediments of different fractions. The sorption isotherms of 600℃ heating fractions were detailed using the linear model, while the other fractions were nonlinear and fitted well with the Freundlich carbon （DOC） removed, model. The dissolved organic NaOH extracted, and 375℃ heating fractions showed more nonlinear sorption than the original sediments, which suggested more heterogeneous sorption sites in these fractions. Compared to the original sediments, the 375~C heating fractions had higher carbon- normalized distribution coefficient （Koc） values, indicating a higher sorption affinity for HHCB. Among the different sediment fractions, the contribution of the 600℃ heating fractions to the overall sorption were the lowest （ 〈 20%）, while the 375℃ heating fractions were the highest （up to 85%）.
