By using equilibrium dialysis, atomic absorption spectrometry, fluorescence titration and determination of fluorescence lifetime, it can be determined that each fibrinolytic principle(FP) molecule contains one Ca 2...By using equilibrium dialysis, atomic absorption spectrometry, fluorescence titration and determination of fluorescence lifetime, it can be determined that each fibrinolytic principle(FP) molecule contains one Ca 2+ binding site and one Ca 2+ ion. The energy transfer between Tb 3+ and the Trp residue in FP was studied through fluorescence spectroscopy. Our studies show that the Ca 2+ ion in an FP molecule can be substituted by Tb 3+ ion. In FP molecule, the excition energy can be transfered from the Trp residue as an energy donor to Tb 3+ as an acceptor, substituted into FP and located near the Trp residue. The distance between Tb 3+ and the Trp residue, ~0 375 nm, was worked out with the experimental data and Forster theory.展开更多
A reactive Tb(III) complex with 2-aminobenzoic acid(2-ABAH) and acrylonitrile(AN) as ligands was synthesized.The structure of the complex was characterized by elemental analysis and Fourier transform infrared sp...A reactive Tb(III) complex with 2-aminobenzoic acid(2-ABAH) and acrylonitrile(AN) as ligands was synthesized.The structure of the complex was characterized by elemental analysis and Fourier transform infrared spectrometry(FT-IR).The results indicated that the ligands were coordinated with Tb(III) ion.Thermal gravity-derivative thermogravimetric(TG-DTG) analysis indicated that the complex kept stable up to 198 oC.Luminescence properties were investigated by UV-vis absorption spectra and fluorescence spectra.The results suggested that being excited at 361 nm,the complex exhibited characteristic emission of Tb(III) ion,revealing that the complex could be excited by 365 nm ultraviolet chip.The HOMO and LUMO,ΔE(HOMO-LUMO),molecular frontier orbital,and the singlet state and triplet energy state levels of the ligands were calculated at the B3LYP/6-31+G(d) level.The results indicated that intramolecular energy transfer mechanism followed Dexter exchange energy transfer theory.Both the calculation for excited state of ligand and energy transfer mechanism could provide the theoretical basis for the design of high luminescent materials of rare earth complexes with organic ligands.展开更多
Poly (N-vinylacetatnide) ( PNVA) was synthesized by free radical polymerization in ethanol solution, in which alpha, alpha'-azobisisobutyronitrile was used as an initiator. Tb(III)-PNVA polymer was prepared and ch...Poly (N-vinylacetatnide) ( PNVA) was synthesized by free radical polymerization in ethanol solution, in which alpha, alpha'-azobisisobutyronitrile was used as an initiator. Tb(III)-PNVA polymer was prepared and characterized by ultraviolet-visual (UV), fourier transform infrared (FIF-IR), X-ray photoelectron spectroscopy (XPS) and fluorescence spectroscopy. The experimental results of UV, FT-IR and XPS show that the Tb (III)-PNVA electrovalent complex is formed by electrostatic interaction between terbium (III) cation and complexible atoms of acylamino group in the pendant chain of the polymer. The fluorescence spectrum of the complex exhibits intensive characteristic emission of terbium at 490, 545 and 584 run, which are assigned to D-5(4)->F-7(6), D-5(6)->F-5(6) and D-5(4)->F-7(3) transition, indicating that there exists an efficient intermolecular energy transfer from the polymer ligand to the central rare earth ion. The emission intensity of the complex is increased with the increasing concentration of Tb (III) ion until the weight ratio of Tb (III) on to PNVA is 1.5% (mass fraction), and decreased with the further increasing concentration of Tb (III) ion, which is a typical concentration quenching behavior.展开更多
A new rare earth complex Tb(p-MBA)_3phen was synthesized, which is first used as an emitting material in organic electroluminescence. By doping it into the conjugated polymer PVK, single-layer and double-layer devices...A new rare earth complex Tb(p-MBA)_3phen was synthesized, which is first used as an emitting material in organic electroluminescence. By doping it into the conjugated polymer PVK, single-layer and double-layer devices were fabricated with structures: device 1: ITO/PVK∶Tb(p-MBA)_3phen/Al; device 2∶ ITO/PVK: Tb(p-MBA)_3phen/AlQ/LiF/Al. The characteristics of these devices have been investigated. The emission of PVK is completely restrained, and only the pure green emission from Tb^(3+) can be observed in electroluminescence. The optimized device 2 has better monochromatic characteristics with the maximal brightness of 152 cd·m^(-2) at the voltage of 20 V.展开更多
The phosphate glass doped with Gd^3+, Tb^3+ and Gd^3+/Tb^3+ were prepared by high temperature melting. The photo-luminescence behavior of Gd^3+ and Tb^3+ in phosphate glass were investigated by absorption, excit...The phosphate glass doped with Gd^3+, Tb^3+ and Gd^3+/Tb^3+ were prepared by high temperature melting. The photo-luminescence behavior of Gd^3+ and Tb^3+ in phosphate glass were investigated by absorption, excitation, and emission spectroscopy. Energy transfer between Gd3+ and Tb3+ in phosphate glass was studied, and it was found that there were two energy transfer mechanisms between Gd3+ and Tb3+ in phosphate glass: one was from 4f7 level of Gd3+ to the 4f8 level of Tb3+, and the other was from 5d level of Tb^3+to 4f^7 level of Gd^3+. The new findings would be beneficial for the study of Tb^3+-doped scintillating phosphate glass.展开更多
The glass-forming regions of tellurium-gadolinium-tungsten ternary system prepared at 1000℃for 60 min were firstly determined.To improve density,the full replacement of lutetium for gadolinium to form Tb^(3+)-activat...The glass-forming regions of tellurium-gadolinium-tungsten ternary system prepared at 1000℃for 60 min were firstly determined.To improve density,the full replacement of lutetium for gadolinium to form Tb^(3+)-activated tellurium-lutetium-tungsten glasses with the composition of 64 TeO_(2)-20 WO_(3)-(16-y)Lu_(2)O_(3)-yTb_(2)O_(3)were designed for scintillation application.The concentration-dependent optical properties of Tb^(3+)-activated tellurium-lutetium-tungsten glasses were fully investigated by transmittance,excitation and emission spectra,together with the luminescence decay curves.The energy transfer mechanism was discussed according to Huang’s rule.The optimized 4 mol%Tb_(2)O_(3)activated tellurium-lutetium-tungsten glasses with the density of 6.49 g/cm^(3)and the lifetime of 0.551 ms are developing to be suitable for the potential detection of slow events in the future work.展开更多
文摘By using equilibrium dialysis, atomic absorption spectrometry, fluorescence titration and determination of fluorescence lifetime, it can be determined that each fibrinolytic principle(FP) molecule contains one Ca 2+ binding site and one Ca 2+ ion. The energy transfer between Tb 3+ and the Trp residue in FP was studied through fluorescence spectroscopy. Our studies show that the Ca 2+ ion in an FP molecule can be substituted by Tb 3+ ion. In FP molecule, the excition energy can be transfered from the Trp residue as an energy donor to Tb 3+ as an acceptor, substituted into FP and located near the Trp residue. The distance between Tb 3+ and the Trp residue, ~0 375 nm, was worked out with the experimental data and Forster theory.
基金Project supported by the Program for Changjiang Scholar and Innovative Research Team in University (IRT0972)the International Cooperation Program of Shanxi Province (2009081046)the Postgraduate Innovation Program of Shanxi Province (20103023)
文摘A reactive Tb(III) complex with 2-aminobenzoic acid(2-ABAH) and acrylonitrile(AN) as ligands was synthesized.The structure of the complex was characterized by elemental analysis and Fourier transform infrared spectrometry(FT-IR).The results indicated that the ligands were coordinated with Tb(III) ion.Thermal gravity-derivative thermogravimetric(TG-DTG) analysis indicated that the complex kept stable up to 198 oC.Luminescence properties were investigated by UV-vis absorption spectra and fluorescence spectra.The results suggested that being excited at 361 nm,the complex exhibited characteristic emission of Tb(III) ion,revealing that the complex could be excited by 365 nm ultraviolet chip.The HOMO and LUMO,ΔE(HOMO-LUMO),molecular frontier orbital,and the singlet state and triplet energy state levels of the ligands were calculated at the B3LYP/6-31+G(d) level.The results indicated that intramolecular energy transfer mechanism followed Dexter exchange energy transfer theory.Both the calculation for excited state of ligand and energy transfer mechanism could provide the theoretical basis for the design of high luminescent materials of rare earth complexes with organic ligands.
文摘Poly (N-vinylacetatnide) ( PNVA) was synthesized by free radical polymerization in ethanol solution, in which alpha, alpha'-azobisisobutyronitrile was used as an initiator. Tb(III)-PNVA polymer was prepared and characterized by ultraviolet-visual (UV), fourier transform infrared (FIF-IR), X-ray photoelectron spectroscopy (XPS) and fluorescence spectroscopy. The experimental results of UV, FT-IR and XPS show that the Tb (III)-PNVA electrovalent complex is formed by electrostatic interaction between terbium (III) cation and complexible atoms of acylamino group in the pendant chain of the polymer. The fluorescence spectrum of the complex exhibits intensive characteristic emission of terbium at 490, 545 and 584 run, which are assigned to D-5(4)->F-7(6), D-5(6)->F-5(6) and D-5(4)->F-7(3) transition, indicating that there exists an efficient intermolecular energy transfer from the polymer ligand to the central rare earth ion. The emission intensity of the complex is increased with the increasing concentration of Tb (III) ion until the weight ratio of Tb (III) on to PNVA is 1.5% (mass fraction), and decreased with the further increasing concentration of Tb (III) ion, which is a typical concentration quenching behavior.
文摘A new rare earth complex Tb(p-MBA)_3phen was synthesized, which is first used as an emitting material in organic electroluminescence. By doping it into the conjugated polymer PVK, single-layer and double-layer devices were fabricated with structures: device 1: ITO/PVK∶Tb(p-MBA)_3phen/Al; device 2∶ ITO/PVK: Tb(p-MBA)_3phen/AlQ/LiF/Al. The characteristics of these devices have been investigated. The emission of PVK is completely restrained, and only the pure green emission from Tb^(3+) can be observed in electroluminescence. The optimized device 2 has better monochromatic characteristics with the maximal brightness of 152 cd·m^(-2) at the voltage of 20 V.
基金Project supported by the National Natural Science Foundation of China (50902137 and 60937003)
文摘The phosphate glass doped with Gd^3+, Tb^3+ and Gd^3+/Tb^3+ were prepared by high temperature melting. The photo-luminescence behavior of Gd^3+ and Tb^3+ in phosphate glass were investigated by absorption, excitation, and emission spectroscopy. Energy transfer between Gd3+ and Tb3+ in phosphate glass was studied, and it was found that there were two energy transfer mechanisms between Gd3+ and Tb3+ in phosphate glass: one was from 4f7 level of Gd3+ to the 4f8 level of Tb3+, and the other was from 5d level of Tb^3+to 4f^7 level of Gd^3+. The new findings would be beneficial for the study of Tb^3+-doped scintillating phosphate glass.
基金the National Natural Science Foundation of China(11765009)the Major Discipline Academic and Technical Leaders Training Program of Jiangxi Province(20172BCB22023)+1 种基金the Science&Technology Project of Shaoguan City in Guangdong Province(2018CS11905)the Innovation and Entrepreneurship Training Program of College Students(202010419025)。
文摘The glass-forming regions of tellurium-gadolinium-tungsten ternary system prepared at 1000℃for 60 min were firstly determined.To improve density,the full replacement of lutetium for gadolinium to form Tb^(3+)-activated tellurium-lutetium-tungsten glasses with the composition of 64 TeO_(2)-20 WO_(3)-(16-y)Lu_(2)O_(3)-yTb_(2)O_(3)were designed for scintillation application.The concentration-dependent optical properties of Tb^(3+)-activated tellurium-lutetium-tungsten glasses were fully investigated by transmittance,excitation and emission spectra,together with the luminescence decay curves.The energy transfer mechanism was discussed according to Huang’s rule.The optimized 4 mol%Tb_(2)O_(3)activated tellurium-lutetium-tungsten glasses with the density of 6.49 g/cm^(3)and the lifetime of 0.551 ms are developing to be suitable for the potential detection of slow events in the future work.