Separation of radioactive terbium from massive Gd targets for medical use

Journal of Radioanalytical and Nuclear Chemistry - Methods for chemical separation of terbium from gadolinium and dysprosium have been investigated using proton activated gadolinium, as well as...     

Spectrophotofluorometric determination of terbium and europium in potassium carbonate solution

The conditions for the spectrophotofluorometric determination of terbium and europium, in solutions of potassium carbonate, have been established. The apparent excitation and fluorescence wavelengths used, respectively, are 245 mmu and 550 mmu for terbium and 400 mmu and 620 mmu for europium. The fluorescence varies linearly with the concentration of terbium and europium in the range 0.3-70 mug, of terbium/ml and 4-800 mug of europium/ml. Large amounts of gadolinium, lutetium and yttrium do not interfere. Cerium(IV) interferes seriously.     

Vacuum fusion determination of oxygen in gadolinium,terbium metal and iron-terbium alloy

The extraction conditions for the accurate determination of oxygen in gadolinium, terbium and iron-terbium alloy using vacuum fusion analysis were studied. The influence of the gettering effect, the analyzing temperature and the weight ratio of the bath metal to the sample were investigated. Oxygen values of gadolinium and terbium were measured by the graphite crucible, the graphite capsule, the tin bath, the iron-tin bath and the platinum-tin bath techniques in the temperature range of 1500–2100 °C using vacuum fusion analysis. These oxygen values were compared with those obtained by inert gas fusion analysis. In inert gas fusion analysis, the samples were analyzed with iron and tin in a tin capsule, and the samples with platinum in a tin capsule were analyzed in a graphite capsule enclosing with carbon powder. Oxygen values of both metal samples in the graphite capsule at 2000 °C, with an iron-tin bath at 1850 °C and a platinum-tin bath at 2000 °C in vacuum fusion analysis, were respectively in good agreement within their errors; the oxygen values of gadolinium were also in good agreement with that from inert gas fusion analysis in the iron-tin bath, but those of terbium were not in agreement. This agreement for gadolinium guarantees the reliability of the conditions for the accurate determination, and the difference of oxygen values for terbium suggests a need for further consideration on the conditions of the inert gas fusion analysis.     

Optical characteristics of europium and terbium doped strontium orthogermanate phosphors

In this work, europium and terbium activated Sr₂GeO₄ phosphors were successfully developed by traditional solid state method. Powders XRD, FESEM, EDS, FTIR, DRS and PL techniques have been used to probe the as prepared phosphors. Powder XRD patterns of the phosphors are indexed. The elemental composition of phosphors was obtained from their EDS. FTIR spectra are employed to detect different vibrational groups in phosphor compositions. The DRS profiles of both pristine and Eu³⁺ (Tb³⁺) substituted samples exhibit broad and strong band in the 230–370 ​nm region. The photoluminescence studies of europium and terbium doped phosphors exhibited optimistic red emission at 617 ​nm (⁵D₀ → ⁷F₂ of Eu³⁺ ions) and intense green emission at 543 ​nm (⁵D₄ → ⁷F₅ of Tb³⁺ ions) upon ultraviolet (UV) excitations respectively. The CIE chromaticity co-ordinates are produced in deep red and green regions. Therefore, these materials may become potential alternatives for red and green phosphors in the display devices and in lamp industry.     

Emissive terbium probe for multiphoton in vitro cell imaging

A polymeric terbium complex that can be excited by near-infrared excitation at 800 nm via multiphoton absorption processes has been synthesized. This complex has been demonstrated to show strong, observable, three-photon-induced f-f emission in cell imaging. In vitro studies carried out in three carcinoma cell lines (A549, HONE1, and HeLa) have been performed and shown to have low cytotoxicity. This complex is therefore a potential candidate for future infrared excitation imaging dyes.     

表面活性剂存在下铽-镥(钆、钇)-乙酰水杨酸共发荧光体系的研究

本文研究了镥等三种稀土离子与铽-乙酰水杨酸配合物产生的共发荧光效应。在最佳条件下,Lu³⁺、Gd³⁺、Y³⁺的存在可使铽-乙酰水杨酸配合物的荧光分别增强108,58和73倍。讨论了共发光体系的形成条件和荧光特性。利用Tb-Lu-乙酰水杨酸体系和Tb-Lu-乙酰水杨酸-乙二胺四乙酸-十六烷基三甲基溴化铵体系分析了合成稀土样品和包头稀土标准氧化物中的铽,结果满意,加标回收率为90.5～105.6%,并对共发光的机理和表面活性剂的作用进行了初步探讨。     

Séparation chromatographique des lanthanides en deux groupes basée sur des différences dans la cinétique de décomposition des complexes lanthanides-macrocyclesChromatographic separation of lanthanides into two groups based on kinetic differences in the decomposition of macrocycle/lanthanide complexes

The separation of the lanthanides in two groups, based on differences in decomplexation rates of the LnDOTA entities (DOTA = 1,4,7,10-tetraazacyclododecane-N,N′,N″,N?-tetraacetic acid), is achieved on a sulphonate cation-exchange column (H⁺ form). The yttrium earths, from terbium to lutetium, are eluted first as Ln-DOTA-H species with 1.25 M HCl; the light lanthanides, from lanthanum to samarium inclusive, are eluted as uncomplexed ions at the end of the chromatogram, with more concentrated hydrochloric acid. Given an equimolar mixture of the Eu-DOTA and Gd-DOTA complexes as starting solution, 40% of the gadolinium can be recovered free from europium at the start of elution and 47% of the europium free from gadolinium at the end of the elution.     

Simultaneous determination of samarium, europium and terbium with quinaldic acid and phenanthroline by synchronous derivative fluorimetry

Synchronous derivative fluorescence of samarium, europium and terbium complexes with quinaldic acid and phenanthroline was examined in aqueous solution. The composition of these complexes was determined. The maximum emission wavelengths are 645 nm, 617 nm and 545 nm for samarium, europium and terbium, respectively. Under the optimal experimental conditions, the fluorescence intensity was a linear function of concentration in the range of 10-250 ppm for samarium, 0.5-50 ppm for europium and 0.5-300 ppm for terbium. Simultaneous determination of samarium, europium and terbium was successfully carried out for samarium oxide and middle rare earth mixture. The precision of the method, expressed as relative standard deviation, is within 1.1-2.5%.     

氟化镁锶中铕和铽的电荷迁移及其平衡解析

在氩气氛中，合成子ＳｒＭｇＦ４：ｘＥｕ，ｙＴｂ复合氟化物磷光体，该体系中Ｅｕ＾３＋和Ｅｕ＾２＋共存，随共掺入Ｔｂ浓度的增加，Ｅｕ＾３＋的荧光发射强度降低，Ｅｕ＾３＋的发光增强，并且Ｅｕ＾２＋的ＥＳＲ信号增强，认为Ｅｕ＾３＋和Ｔｂ３＋之间存在的电荷迁移，即Ｅｕ＾３＋Ｔｂ＾３＋→Ｅｕ＾２＋＋Ｔｂ＾４＋，通过半量手段研究了这一电荷迁移反应的平衡常数。     

Luminescent properties of Ba_3(PO_4)_2:Eu,Tb phosphors

Luminescence of europium (Ⅲ),europium(Ⅱ) and terbium(Ⅲ) has been observed in Bas(PO4)2:Eu,Tb phosphors which are synthesized in air atmosphere.The valence state of europium is influenced by amount of terbium.It is notable that the relative intensity of the emission spectra peaks corresponding to Eu2+ is increased if the amount of Tb3+ is increased.These phenomena can be explained by an electron transfer mechanism.We predict a new kind of two-rare-earth codoped trichromatic phosphors in Ba3(PO4)2 matrix.     

The application of trimesic acid to the determination of terbium by spectrofluorimetry

A sensitive, direct spectrofluorimetric method for the trace determination of terbium with use of trimesic acid (TMA) has been developed. The reaction conditions for the fluorescence system of terbium with TMA were studied. The terbium ion can form a stable binary chelate with TMA, having a ratio of 1:1 in the pH range 3.5-6.5. The maximum excitation and emission wavelengths are 260 nm and 545 nm for the terbium chelate, respectively. The reaction is instantaneous and the fluorescence intensity of the terbium chelate remains stable from 0.25 to 4 h. Under the optimal experimental conditions the fluorescence intensity is a linear function of concentration in the range 0.0248-6.35 mug ml(-1) of terbium. The relative standard deviation is still within +/-4% in the presence of one-thousandfold amounts of the other lanthanide ions, and common foreign ions hardly interfere in the determination. The method can be employed for the determination of trace amounts of terbium in rare earth ores or oxides because of its high sensitivity and selectivity with good reproducibility and accuracy.     

Spectrofluorimetric trace determination of terbium(III) with potassium oxalate

Potassium oxalate acts as a specific reagent in enhancing the fluorescence intensity of terbium in aqueous solutions. Maximum fluorescence intensity is obtained by irradiating (at 255 mμ) terbium(III) dissolved in 0.01 M potassium oxalate solution at pH 7.8. The enhancement and quenching phenomena caused by other lanthanides, errors in the determination, and various examples of spectrofluorimetric analysis of traces of terbium in mixtures with other lanthanides are described. The sensitivity of the method is 5·10^-2μg/ml of terbium.     

Enhancement of fluorescence of terbium/trimesic acid/cyclodextrin system by zirconate and its application to the determination of terbium

A new approach of fluorescence enhancement for the determination of terbium based on the formation of a new fluorescence system of Tb-TMA-beta-CD (benzene-1,3,5-tricarboxylic acid (TMA), beta-cyclodextrin (beta-CD)) in an aqueous medium of pH 5.0 provided by a HAc-NaAc buffer in the presence of an oxy-acid of transition metal, zirconate acid, is reported. The maximum excitation and emission wavelengths are 301 nm and 545 nm for the terbium complex, respectively. Under the optimal conditions, the method allows the determination of terbium over the range of 0.508-521 ng ml(-1) with a S.D. of 0.392, and the recovery is in the range of 99.0-100.1%. The emulsion formed by Tb-TMA-beta-CD with zirconate acid makes the determinate system more stable than the system of Tb-TMA-beta-CD. The proposed method has been employed for the determination of some international standard reference or samples with a good precision (RSD < 1.7%, n = 5).     

活性铽三元荧光配合物的合成、表征及性能研究

本文以对甲基苯甲酸、对氨基苯甲酸、磺基水杨酸、大茴香酸、间氯苯甲酸为第一配体,丙烯腈为活性配体,合成了五种新的铽芳香羧酸丙烯腈三元配合物。通过元素分析,EDTA配位滴定分析,热分析,红外、紫外、荧光光谱分析对目标配合物的组成、结构进行了表征,并研究了它们的发光性能。结果表明,五种新的活性铽三元配合物均具有良好的发光性能,各芳香羧酸向铽离子传递光能的动力为:大茴香酸>对甲基苯甲酸>间氯苯甲酸>磺基水杨酸>对氨基苯甲酸,将这些含活性配体丙烯腈的发光铽配合物引入高分子化合物中可望合成出键合型铽高分子发光材料。     

X-ray fluorescence analysis of terbium oxide and oxalate for rare earth impurities

Summary A method for the determination of samarium, europium, gadolinium, dysprosium, holmium and yttrium oxides in terbium oxide is described. The sample is converted to terbium oxalate, mixed with boric acid binder in the ratio 21, pelleted at a pressure of 20 tons over a boric acid backing pellet and irradiated with X-rays from a tungsten tube operated by Philips PW 1140 generator. The secondary X-rays thus generated are analysed by a LiF(200) crystal in Philips PW 1220 X-ray fluorescence spectrometer. The minimum determination limit is 0.01% for all rare earth oxides determined except for yttrium oxide for which it is 0.005%.

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Zusammenfassung Eine Methode zur Bestimmung der Oxide von Samarium, Europium, Gadolinium, Dysprosium, Holmium und Yttrium in Terbiumoxid wurde beschrieben. Die Probe wird zu Terbiumoxalat umgesetzt, mit Borsäure im Verhältnis 2 1 gemischt, mit 20 Tonnen Druck auf eine Borsäuretablette aufgepreßt und mit Röntgenstrahlen aus einer Wolframröhre bestrahlt, die mit einem Philips-Generator PW 1140 gespeist wurde. Die dabei entstehenden Sekundärstrahlen wurden mit Hilfe eines LiF-Kristalls (200) in einem Philips PW 1220 Röntgenfluoreszenz-Spektrometer analysiert. Die untere Grenze der Bestimmbarkeit liegt bei 0,01% für alle bestimmten Seltenerden-Oxide mit Ausnahme von Yttriumoxid mit 0,005%.

     

Structure of a terbium(III)-quinizarine complex: the first crystallographic model for metalloanthracyclines

The crystal structure of a complex of terbium(III) with quinizarine 2-sulfonate has been solved by single-crystal X-ray diffraction methods. The metal cation is coordinated by two adjacent phenolate and quinone oxygens of the anthraquinone moiety of a quinizarine sulfonate anion and by six water molecules. To our knowledge, this is the first structure of a metal complex of the 1,4-dihydroxy anthraquinone ligand. On the basis of strict similarities in the spectroscopic features of the terbium adducts with either doxorubicin or quinizarine 2-sulfonate, the present structure is proposed as a model for the metal complexes of anthracyclines.     

Aqueous solution of terbium as a scintillator for registration of actinoid alpha-radiation

A scintillator, based on the direct effect of a radiation upon a dissolved activator, has been suggested. Concentrated /2–2.5 mol/1/ solutions of Tb³⁺ in D₂O and H₂O, and aqueous solutions of HCl, HNO₃, and HClO₄ have been found to possess a high light output of scintillations affected by -particles of actionoids. The scintillation efficiency of terbium solution in D₂O is higher than that of some well-known organic scintillators. The terbium scintillator is quenched feebly by actinoid salts. Besides, it is of low sensitivity for the - and -radiation. The scintillations in terbium solutions represent groups of separate single-electron pulses with an exponentially decreasing frequency of their occurrence within groups.     

MMgF4(M=Ca,Sr, Ba)体系中Eu和Tb的电荷迁移

于不同气流中, 合成了MMgF4:xEu,yTb复合氟化物磷光体。该体系中Eu^3^+和Eu^2^+共存。Tb的存在影响Eu的价态存在形式。ESR测试表明, 随Tb的掺入浓度增加, Eu^2^+的浓度呈规律性变化。随Eu的掺入, 样品的XPS谱中出现了四价铽的Tb3d5/2特征伴峰。认为Eu^3^+和Tb^3^+之间存在电荷迁移平衡。即Eu^3^++Tb^3^+=Eu^2^++Tb^4^+。通过半定量手段研究了SrMgF4中这一衡的平衡常数。     

Mass-spectrometric study of molecular and ionic sublimation of gadolinium and terbium tribromides in Knudsen and Langmuir modes

Molecular and ionic sublimation of gadolinium and terbium tribromides in Knudsen and Langmuire modes was studied by the method of high-temperature mass-spectrometry. On the basis of obtained enthalpies of sublimation and ion-molecule reactions the enthalpies of formation of LnBr₃ and Ln₂Br₆ molecules and LnBr ₄ ^? and Ln₂Br ₇ ^? negative ions were determined. For the first time the electron work function for crystals of the studied tribromides was calculated.     

Spectrophotometric study of the cation-induced dimerization of heteroleptic terbium(III) tetra-15-crown-5-bisphthalocyaninate

We proposed a new approach to the synthesis of heteroleptic crown-substituted terbium(III) bisphthalocyaninate, [(15C5)₄Pc]Tb(Pc) (1) based on the reaction of unsubstituted lanthanum bisphthalocyaninate (La(Pc)₂) with tetra-15-crown-5-phthalocyanine (H₂[(15C5)₄Pc]) and terbium(III) acetate in a mixture of octanol and chloronaphthalene in the presence of 1,8-diazabicyclo[ 5.4.0]undec-7-ene as an organic base. For the first time, we carried out a comparative spectrophotometric titration of compound 1 with MBPh₄ solutions (M = K, Rb, Cs) and demonstrated the formation of isostructural cofacial supramolecular dimers. Spectral-structural correlations were developed for evaluation of the distances between phthalocyanine ligands in new supramolecular assemblies, which can be used for the development of polynuclear suprasingle-molecule magnetic materials.