The stability constants of binary complexes Ln-L (Ln = La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+ Tb3+, Dy3+, Ho3+, L = N, N'-bis (2'-pyridine) methyl-1, 10-phenanthroline-2, 9-dimethanamine) were determined by ...The stability constants of binary complexes Ln-L (Ln = La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+ Tb3+, Dy3+, Ho3+, L = N, N'-bis (2'-pyridine) methyl-1, 10-phenanthroline-2, 9-dimethanamine) were determined by pH potentiometric titration method at 25 +/- 0.1degreesC in 0.1 mol . L-1 NaClO4. The probable structures of the corresponding complexes were proposed. The influence of the metal ions to the stability of binary complexes and the stability difference between the complexes of rare earth ion and the corresponding complexes of Co2+, Ni2+, Cu2+ ions were discussed. The stability constants of the corresponding binary complex of radioactive Pm3+ ion were estimated by linear regression.展开更多
This paper describes the synthesis of FER zeolite using commercially available 4-(aminomethyl)pyridine as organic structure-directing agent(OSDA). FER zeolites were prepared in mixtures with SiO2/Al2O3 molar ratios in...This paper describes the synthesis of FER zeolite using commercially available 4-(aminomethyl)pyridine as organic structure-directing agent(OSDA). FER zeolites were prepared in mixtures with SiO2/Al2O3 molar ratios in a narrow range and the resultant products possessed a typical flake-shaped morphology. The crystallization of FER zeolite was tracked in order to better understand the formation mechanism and the products obtained at different crystallization time were systematically characterized using multiple techniques. It showed that a majority of Si atoms and nearly all the Al atoms transformed into the solid phase during the hydrothermal synthesis. The rearrangement of inorganic species gave rise to zeolitic 5-membered rings(5-MRs) and 6-membered rings(6-MRs). Consequently, FER zeolite crystals were formed by the consumption of amorphous bulky gel/solid matrix. Tracking the synthesis process of FER can help.展开更多
文摘The stability constants of binary complexes Ln-L (Ln = La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+ Tb3+, Dy3+, Ho3+, L = N, N'-bis (2'-pyridine) methyl-1, 10-phenanthroline-2, 9-dimethanamine) were determined by pH potentiometric titration method at 25 +/- 0.1degreesC in 0.1 mol . L-1 NaClO4. The probable structures of the corresponding complexes were proposed. The influence of the metal ions to the stability of binary complexes and the stability difference between the complexes of rare earth ion and the corresponding complexes of Co2+, Ni2+, Cu2+ ions were discussed. The stability constants of the corresponding binary complex of radioactive Pm3+ ion were estimated by linear regression.
基金This work was supported by the National Key R&D Program of China (No.2017YFB0702800)the National Natural Science Foundation of China (Nos.21972168,21802168).
文摘This paper describes the synthesis of FER zeolite using commercially available 4-(aminomethyl)pyridine as organic structure-directing agent(OSDA). FER zeolites were prepared in mixtures with SiO2/Al2O3 molar ratios in a narrow range and the resultant products possessed a typical flake-shaped morphology. The crystallization of FER zeolite was tracked in order to better understand the formation mechanism and the products obtained at different crystallization time were systematically characterized using multiple techniques. It showed that a majority of Si atoms and nearly all the Al atoms transformed into the solid phase during the hydrothermal synthesis. The rearrangement of inorganic species gave rise to zeolitic 5-membered rings(5-MRs) and 6-membered rings(6-MRs). Consequently, FER zeolite crystals were formed by the consumption of amorphous bulky gel/solid matrix. Tracking the synthesis process of FER can help.
