p-t-Butyl-calixarene bonded silica stationary phase(CBS) for high performance liquid chromatography was prepared via condensation reaction on the surface of solid .The stationary phase was characterized by means of el...p-t-Butyl-calixarene bonded silica stationary phase(CBS) for high performance liquid chromatography was prepared via condensation reaction on the surface of solid .The stationary phase was characterized by means of elemental analysis and FTIR. The chromatographic performance of CBS was studied by using disubstituted benzenes as the solutes and methanol-water or methanol-buffer as the mobile phases, and compared with that obtained on CPS and ODS. The results show that the chromrtographic process can proceed in various retention mechanism, such as π-π, hydrogen-bonding, charge-transfer and inclusion complexation, besides hydrophobic interaction.展开更多
Three Ce 4+ complexes Ce(p tert butylcalixarene)·(dmf) 4·H 2O (complex A), Ce(p tert butylcalixarene) 2·(dmf) 10 (complex B) and Ce(p tert butylcalixarene)·(dmf) 4 (complex C) w...Three Ce 4+ complexes Ce(p tert butylcalixarene)·(dmf) 4·H 2O (complex A), Ce(p tert butylcalixarene) 2·(dmf) 10 (complex B) and Ce(p tert butylcalixarene)·(dmf) 4 (complex C) were prepared from N,N dimethylforamide (dmf) solution of Ce(NO 3) 3. Their thermal stability, optical properties and coordination features were investigated with thermogravimetric and differential thermal analysis, ultraviolet and visible spectrophotometer, fluorescence spectrophotometer, infrared spectroscopy, and 1H NMR spectrometer. In the solvents of C 6H 6, 1,2 dichloroethane and dmf, complexes A and B can exhibit a ligand to metal charge transfer transition lying in ca. 20000 cm -1 in the electronic spectra. Complex A displays a dimeric structure in C 6D 6 solution. Ce 4+ ions in the complexes are coordinated by phenolic groups of the ligands, oxygen atoms of dmf molecules, and / or OH - ions.展开更多
文摘p-t-Butyl-calixarene bonded silica stationary phase(CBS) for high performance liquid chromatography was prepared via condensation reaction on the surface of solid .The stationary phase was characterized by means of elemental analysis and FTIR. The chromatographic performance of CBS was studied by using disubstituted benzenes as the solutes and methanol-water or methanol-buffer as the mobile phases, and compared with that obtained on CPS and ODS. The results show that the chromrtographic process can proceed in various retention mechanism, such as π-π, hydrogen-bonding, charge-transfer and inclusion complexation, besides hydrophobic interaction.
文摘Three Ce 4+ complexes Ce(p tert butylcalixarene)·(dmf) 4·H 2O (complex A), Ce(p tert butylcalixarene) 2·(dmf) 10 (complex B) and Ce(p tert butylcalixarene)·(dmf) 4 (complex C) were prepared from N,N dimethylforamide (dmf) solution of Ce(NO 3) 3. Their thermal stability, optical properties and coordination features were investigated with thermogravimetric and differential thermal analysis, ultraviolet and visible spectrophotometer, fluorescence spectrophotometer, infrared spectroscopy, and 1H NMR spectrometer. In the solvents of C 6H 6, 1,2 dichloroethane and dmf, complexes A and B can exhibit a ligand to metal charge transfer transition lying in ca. 20000 cm -1 in the electronic spectra. Complex A displays a dimeric structure in C 6D 6 solution. Ce 4+ ions in the complexes are coordinated by phenolic groups of the ligands, oxygen atoms of dmf molecules, and / or OH - ions.
