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To develop the polymeric adsorbent that possess anionic exchangeable function, PP-g-AA-Am fibers were prepared by photoinduced grafting of acrylic acid (AA) onto polypropylene (PP) nonwoven fibers and subsequent conversion of carboxyl group in grafted AA to an amine (Am) group by reaction with diethylene triamine (DETA). The amination of grafted AA increased with increase in the degree of grafting, the reaction time and temperature of the chemical modification process. Catalytic effect of metal chlorides such as AlCl(3) and FeCl(3) on the amination of grafted AA was significant but not essential to lead the amination. FT-IR and solid (13)C NMR data indicate that amine group was introduced into PP-g-AA fiber through amide linkage between grafted AA and DETA. The anion exchange capacity of PP-g-AA-Am fiber increased with increase in the degree of amination, but reached maximum value at about 60% amination of 150% grafted AA. PP-g-AA-Am fiber showed much higher maximum capacity for PO(4)-P and a similar capacity for NO(3)-N compared to commercial anion resins. Furthermore, the PP-g-AA-Am fiber also has adsorption ability for cations because of unaminated residual carboxyl group.

For the ZnSO4–Na2SO4–H2SO4–NaOH–H2O system, a chemical model was developed to predict the hydrogen ion activity at 25 °C. This chemical model consisted of chemical equilibria, and mass and charge balance equations. The activity coefficients of solutes and the activity of water were calculated by using the Pitzer equation. The distribution of sulfate species as a function of the electrolyte concentration was obtained from the model. In the range of 0.5–4.3 m ionic strength of the solution, the experimental pH values were in good agreement with the predicted pH values. The mean activity coefficients of NaOH calculated by the Pitzer equation agreed well with the experimental values obtained from the literature.

A systematic and practical method for the determination of the concentration of the isotopic composition of Sr and Nd and rare-earth elements (REE) from a single sample solution has been developed by combining and improving classical cation-exchange chromatography (CCEC) and modern high-performance liquid chromatography (HPLC). The first step was used to separate Sr and the REE group from a dissolved rock solution by CCEC with a column of large volume and a combination of HClHNO3 as an eluent. The second step was used to separate individual REE components present within the REE group by HPLC, simultaneously quantify them with a post-column reaction detector, and collect Nd with a programmable fraction collector. Separated Sr and Nd fractions were then purified by another CCEC with a column of small volume and HCl as an eluent prior to the mass spectrometric analysis. The analytical results obtained for a series of standard rocks showed a good agreement with recommended values to within ± 10% for REE quantification at the 95% confidence level and ±0.004% (1σ) for the 87 Sr 86 Sr and 143 Nd 144 Nd isotopic ratios.