铽 —氟哌酸荧光体系及氟哌酸测定的研究

用荧光光度法对铽与氟哌酸形成的络合物作了研究，并对络合物分子内部能量传递的机理及其影响因素作了探讨，方法的检测限为５×１０－８ｍｏｌ／Ｌ。对不经任何处理的血清及片剂进行测定，回收率在９４．０％～１０６％和９８．５％～１０５％之间。     

Spectrofluorimetric determination of trace amount of coenzyme II using ciprofloxacin-terbium complex as a fluorescent probe

A new spectrofluorimetric method was developed for the determination of trace amount of nicotinamide adenine dinucleotide phosphate (NADP). Using terbium ion (Tb³⁺)-ciprofloxacin (CIP) complex as a fluorescent probe, in the buffer solution of pH=9.00, NADP can remarkably enhance the fluorescence intensity of the Tb³⁺-CIP complex at and the enhanced fluorescence intensity of Tb³⁺ ion is in proportion to the concentration of NADP. Optimum conditions for the determination of NADP were also investigated. The dynamic range for the determination of NADP is 4.9×10⁻⁷−3.7×10⁻⁶ mol L⁻¹ with detection limit of 1.3×10⁻⁷ mol L⁻¹. This method is simple, practical and relatively free interference from coexisting substances and can be successfully applied to determination of NADP in synthetic water samples. Moreover, the enhancement mechanisms of the fluorescence intensity in the Tb³⁺-CIP system and the Tb³⁺-CIP-NADP system have been also discussed.     

Highly sensitive spectrofluorimetric determination of trace amounts of lecithin

A new spectrofluorimetric method was developed for the determination of trace amounts of lecithin using the ciprofloxacin (CIP)–terbium (Tb³⁺) ion complex as a fluorescent probe. In a buffer solution at pH=5.60, lecithin can remarkably reduce the fluorescence intensity of the CIP–Tb³⁺ complex at λ=545 nm. The reduced fluorescence intensity of the Tb³⁺ ion is proportional to the concentration of lecithin. Optimum conditions for the determination of lecithin were also investigated. The linear range and detection limit for the determination of lecithin were 1.0×10⁻⁶–3.0×10⁻⁵ mol L⁻¹ and 3.44×10⁻⁷ mol L⁻¹, respectively. This method is simple, practical, and relatively free of interference from coexisting substances. Furthermore, it has been successfully applied to assess lecithin in serum samples.      

The energy transfer mechanism in Ce,Tb co-doped LaF3 nanoparticles

LaF₃ pure host, LaF₃:Ce, LaF₃:Tb as well as LaF₃:Ce,Tb phosphors were synthesized by the hydrothermal method. X-ray diffraction measurements were in good agreement with the standard data of LaF₃ from JCPDS card No. 32-0483 and indicated that the material was nanocrystalline with an average particle size of about 36 nm. Photoluminescence spectra of co-doped samples revealed that the Ce³⁺ emission was quenched while Tb³⁺ emission was enhanced, implying that energy was transferred from Ce³⁺ (the donor) to Tb³⁺ (the acceptor) in this system. The luminescence intensities and lifetimes of the donor for different concentrations of the acceptor were fitted to theoretical models in order to investigate the energy transfer mechanism. The quadrupole–quadrupole and exchange interaction mechanisms gave the best fit between the experimental data and the theoretical curves. The effective average Bohr radius from the fit to the exchange model is 0.095 nm. Since this is close to the ionic radii of the Ce³⁺ and Tb³⁺ ions, it suggests that the exchange interaction mechanism contributes to the energy transfer.     

Structural investigations of TiO2:Tb thin films by X-ray diffraction and atomic force microscopy

In this work, structural investigations of TiO₂ thin films doped with Tb at the amount of 0.4, 2 and 2.6 at.% have been outlined. Thin films were deposited on Si and SiO₂ substrates by high energy reactive magnetron sputtering from mosaic Ti-Tb target. The influence of Tb dopant amount, post-annealing treatment and kind of applied substrate on microstructure has been discussed. Thin films were investigated by means of X-ray diffraction (XRD) and atomic force microscopy (AFM). XRD analysis revealed the existence of crystalline TiO₂ in anatase and rutile forms, depending on Tb amount in examined samples. AFM images show that as-deposited samples with 0.4 at.% concentration of terbium (anatase structure) have bigger crystallites as compared to 2% and 2.6 at.% of Tb (rutile structure). The additional annealing at 1070 K results in a mixed anatase (77%) and rutile (23%) structure.     

A Highly Stable (4, 8)-Connected Tb-MOF Exhibiting Efficiently Luminescent Sensing towards Nitroimidazole Antibiotics

A robust 4,8-connected Tb-based metal-organic framework (Tb-MOF) with paddle wheel-shaped {Tb₂(COO)₄} subunits extended by C₃-symmetric 3,3',3''-[1,3,5-benzenetriyltris(carbonylimino)]tris-benzoate connector was hydrothermally synthesized, showing highly environmental stability, good dispersion and intense green emission in water system. Resulting critically from the well suppressed absorption towards the excitation energy, the Tb-MOF exhibits rapid and efficient fluorescent response towards nitroimidazole antibiotics with strong quenching constants and low detection limits of 1.59 × 10⁴ m ^–1 and 2.4 μM for metronidazole as well as 1.62 × 10⁴ m ^–1 and 2.9 μM for dimetridazole. Moreover, the sensitive and selective identification of the Tb-MOF has strong anti-interference and excellent regeneration ability, which endows the promising applications of the Tb-MOF as fluorescent sensing materials.     

TbFCl2: Das erste Fluoridchlorid der dreiwertigen Lanthanoide

TbFCl₂: The First Fluoride Chloride of the Trivalent Lanthanoids Single crystals of TbFCl₂ (monoclinic, C2/c; a = 890.28(5), b = 581.56(3), c = 683.37(4) pm, β = 109.621(4)°; Z = 4) can be obtained by the reaction of TbCl₃ and TbF₃ under inert‐gas atmosphere in tantalum capsules (900 °C, 10 d) as colourless transparent lath‐shaped blocks. The crystal structure contains only one singular Tb³⁺ cation which is eightfold coordinated by two F⁻ (d(Tb³⁺−F⁻) = 218 pm, 2×) and six Cl⁻ anions (d(Tb³⁺−Cl⁻) = 280−287 pm) forming a distorted square antiprism. The F⁻ anions are linear surrounded by two Tb³⁺ cations while the Cl⁻ anions reside in a quasi‐planar coordination of three Tb³⁺ cations, therefore the Niggli formula for TbFCl₂ has to be . Terbium and fluorine form zigzag chains along the c axis that are not connected to each other and arrange like a hexagonal rod‐packing. These cationic chains are mantled by Cl⁻ anions which take care for the charge balance and the three‐dimensional cross‐linkage. The structural relationship of TbFCl₂ with YF₃‐type and PuBr₃‐type will also be discussed.     

Nucleotide/Tb coordination polymer nanoparticles as luminescent sensor and scavenger for nitrite ion

Newly emerged metal organic coordination polymers have aroused the great interest in designing tailored functional materials. In this study, multiple functional components, luminescent Tb³⁺ ion, nucleobase and antenna molecule, were integrated in a single material and prepared into a responsive nanoparticle for nitrite. The terbium coordination polymer nanoparticles made of this kind of material have the dual functions of recognition and transduction and obey a preset sensing mechanism without a post-functionalization of common materials. As the result of the tailored, the terbium coordination polymer nanoparticles are highly sensitive and selective to nitrite by means of Dexter energy transfer between Tb³⁺ ion and nitrite, and can be used for the scavenger for nitrite in aqueous solution. The detection limit, dynamic range and removal capacity of U–Tb–OBBA CPNPs for nitrite are 0.3 µM, 0.3–470 µM and 4.44 mg per gram of particles, respectively. Metal organic coordination polymers show an attractive potential in constructing smart sensing materials.     

A3Ln(Ⅲ)1-xTb(Ⅲ)x(A=邻氨基苯甲酸;Ln=La、Gd、Y; x=0-0.1)稀土配合物的荧光性能

采用共沉淀法合成了掺杂 L a、 Gd、 Y的 Tb-邻氨基苯甲酸配合物 ,研究其荧光性能 ,结果显示 ,掺杂L a、Gd、Y后 ,对 Tb配合物的发光有增敏作用 ,讨论了不同的掺杂离子 (L a、Gd、Y)及掺杂量对其荧光性能的影响。发现 ,当掺杂离子取代大部分 Tb3+时 ,其发光增强仍十分显著。     

螯合剂对铽(Ⅲ)-转铁蛋白配合物的影响

在室温及ｐＨ７．４下,观察了一些螯合剂对铽（Ⅲ）－转铁蛋白配合物的影响．结果表明,铽（Ⅲ）与人血清脱铁转铁蛋白的结合是可逆的;ＥＤＴＡ和次氮基三乙酸可使铽（Ⅲ）－脱铁转铁蛋白配合物定量释放铽（Ⅲ）．用ＥＣＣＬＥＳ程序计算表明,血清中微摩尔数量级的铽（Ⅲ）主要以小分子配合物形式存在,其中铽（Ⅲ）－柠檬酸约占６２％,而铽（Ⅲ）－脱铁转铁蛋白配合物约占２１％