Enhanced fluorescence of 3-tryptimino-1-phenyl-butan-1-one–Tb with 1,10-phenanthroline ternary system, and its analytical application

A new Schiff base ligand, 3-tryptimino-1-phenyl-butan-1-one (TPB), was synthesized. The fluorescence intensity of its terbium(III) complex was greatly enhanced by addition of 1,10-phenanthroline to an acetonitrile solution. Spectrofluorimetric determination of trace amounts of Tb³⁺ was performed based on this effect. The excitation and emission wavelengths are 293 and 546 nm, respectively. Under optimal conditions, the fluorescence intensities varied linearly with the concentration of Tb³⁺ in the range of 2.0 × 10⁻⁶ to 7.0 × 10⁻⁶ M with a detection limit of 2.4 × 10⁻⁹ M. Interference by some rare earth ions is described. This method was applied to the determination of trace amounts of terbium(III) in a high purity Y₂O₃ matrix. The mechanism of fluorescence enhancement was also studied.     

(La1-xREx)2/3Sr1/3MnO3(RE=Y,Sm,Eu,Tb;x=0.1～0.5)的晶体结构及磁性质研究

采用空气中固相反应烧结法制备了一系列钙钛矿结构的(La1-xREx)2/3Sr1/3MnO3(RE=Y,Sm,Eu,Tb;x=0.1～0.5)稀土锰氧化物多晶样品.X射线衍射(XRD)分析表明掺杂RE部分替代La以后,样品的晶体结构为正交结构,空间群为Pbmm.在室温(300K)和液氮温度(77K)下分别测试了样品的磁性质,发现磁性质的改变与RE的掺入量以及RE的离子半径有关.在掺Tb的样品中明显存在巨磁电阻效应,磁场为2 T,温度为300和77 K分别测得(La0.6Tb0.4)2/3Sr1/3MnO3和(La0.7Tb0.3)2/3Sr1/3MnO3的磁电阻(MR)为80%和85%.随着Tb掺杂量的增加,在不同的磁场下,样品电阻-温度关系曲线的峰均向高温方向移动.     

Ca5(PO4)3Cl中铕和铽间的电子转移

本文通过对铕和铽在Ca₅(PO₄)₃Cl基质中的发光特征的研究，发现铕和铽之间存在着电子转移现象，并对其反应机理进行了探讨。Eu³⁺(4f⁶)和Tb³⁺(4f⁸)通过电子转移使它们达到电子结构稳定的Eu²⁺(4f⁷)和Tb⁴⁺(4f<     

Preparation,thermal decomposition process and kinetics for terbium<Emphasis Type="Italic">p</Emphasis>-methoxybenzoate ternary complex with 1,10-phenanthroline

The complex of [Tb₂(p-MOBA)₆(PHEN)₂] (p-MOBA=C₈H₇O₃,p-methoxybenzoate; PHEN=C₁₂H₈N₂, 1,10-phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of Tb₂(p-MOBA)₆(PHEN)₂ in a static air atmosphere was investigated by TG-DTG, DTA, SEM and IR techniques. By the kinetic method of processing thermal analysis data put forward by Malek et al., it is defined that the kinetic model for the first-step thermal decomposition is SB(m,n). The activation energy E for this step reaction is 140.92 kJ mol^-1, the enthalpy of activation H is 136.06 kJ mol^-1, the Gibbs free energy of activation G is 145.16 kJ mol^-1, the entropy of activation S is -15.53 J mol^-1, and the pre-exponential factor lnA is 29.26. The lifetime equation at mass loss of 10% was deduced as ln =-28.72+1.943·10⁴/T by isothermal thermogravimetric analysis.     

Phase diagram and electrical conductivity of TbBr3-NaBr binary system

Several experimental techniques were used to characterise the physicochemical properties of the TbBr₃-NaBr system. The phase diagram determined by DSC, exhibits an eutectic and a Na₃TbBr₆ stoichiometric compound that decomposes peritectically (759 K) shortly after a solid-solid phase transition (745 K). The eutectic composition, x(TbBr₃)=39.5 mol%, was obtained from the Tamman method. This mixture melts at 699 K. With the corresponding enthalpy of about 16.1 kJ mol^-1. Diffuse reflectance spectra of the pure components and their solid mixtures (after homogenisation in the liquid state) confirmed the existence of new phase exhibiting its own spectral characteristics, which may be possibly related to the formation of Na₃TbBr₆ in this system. Additionally, the electrical conductivity of TbBr₃-NaBr liquid mixtures was measured down to temperatures below solidification over the whole composition range. This revised version was published online in July 2006 with corrections to the Cover Date.     

Terbium and holmium trans-2,3-dimethylacrylic acid complexes with 1,10-phenanthroline

Novel dinuclear complexes, [REL₃(phen)]₂ (where RE = Tb, Ho; HL = trans-2,3-dimethylacrylic acid; phen = 1,10-phenantheoline), were synthesized and determined by elemental analysis, infrared absorption spectra (IR), thermogravimetric analysis (TGA), and X-ray diffraction. The Tb complex crystallizes in space group P2_1/n with the cell dimensions a = 12.939(2) Å, b = 13.018(2) Å, c = 15.400(3) Å and = 94.72(1)°. The Ho complex crystallizes in P ⁽⁹⁾ with a = 12.406(3) Å, b = 13.280(3) Å, c = 9.823(2) Å, = 110.80(2)°, = 103.42(2)°, = 63.67(1)°. The Tb atom is nine coordinate and the separation of Tb...Tb* is 3.97 Å. The Ho atom is eight coordinate and the separation of Ho...Ho* is 4.01 Å.     

铥、镱、钇对铽-苯甲酰异羟肟酸配合物荧光的增强作用

本文通过对Tm（Ⅲ）-苯甲酰异羟肟酸（BHA）体系的发射光谱和激发光谱分析,研究了铥、镱和钇离子对Tb-BHA体系的发光性质的增强作用。测得了增敏离子的最佳浓度分别为1.8×10-4mol/L(Tm3+),1.5×10-4mol/L(Yb3+)和2.0×10-4mol/L(Y3+).并对RE-BHA（RE=Tm,Yb,Y和Tb）的固态配合     

铽、钙的L-谷氨酸和L-苏氨酸三元配合物的研究

生物体内是多种生物分子共存的复杂环境,三元配合物广泛存在,并表现了许多重要生物功能.氨基酸是生物体内一类普遍存在的生物配体.游离氨基酸可形成多种具有生物功能的多元配合物.     

NaZnLa(PO4)2中Ce3+和Tb3+的发光

采用高温固相反应合成了NaZnLa(PO₄)₂中掺杂Ce³⁺、Tb³⁺的荧光体,对其晶体结构、发光行为进行了研究,并尝试对NaZnLa(PO₄)₂:Ce,Tb荧光体进行调制。NaZnLa(PO₄)₂是LaPO₄的同构物,为单斜晶系独居石结构,从XRD谱数据得到NaZnLa(PO₄)₂基质的晶胞参数为a=0.6823nm,b=0.7045nm,c=0.6497nm,β=1039°,v=0.303nm³,其晶胞参数与单斜LaPO₄的晶胞参数相似。在NaZnLa(PO₄)₂:Ce,Tb荧光体中,Ce³⁺对Tb³⁺有良好的敏化作用,掺杂适量的BO₃^3-、Al³⁺、Dy³⁺,可以增强发光亮度。