Amount Of Terbium Research Articles

Oxygen ion conductivity of (Yb0.9 − x Tb x Ca0.1)2Ti2O7 − δ solid solutions

We have studied terbium substitution for ytterbium in (Yb0.9 − xTbxCa0.1)2Ti2O7 − δ (x = 0.1, 0.2, 0.3, 0.4) pyrochlore solid solutions synthesized through coprecipitation followed by firing at 1550°C. The results indicate that only a small amount of terbium (less than 10%) can be incorporated into the pyrochlore structure of (Yb0.9Ca0.1)2Ti2O6.9 because of the large difference in ionic radius between the terbium and ytterbium cations: Δr = r(TbCN 83+) − r(YbCN 83+) = 0.055 A. The oxygen ion conductivity of the (Yb0.9 − xTbxCa0.1)2Ti2O7 − δ solid solutions has been determined by impedance spectroscopy in air in the temperature range 300 to 900°C. At high temperatures (t > 640°C), their bulk conductivity was essentially independent of the Yb/Tb ratio. The observed decrease in density and microstructural changes were insignificant. At relatively low temperatures (t < 640°C), the bulk conductivity decreased slightly, and the decrease depended little on terbium concentration.

Thermoluminescence of aluminum oxide co-doped with terbium and thulium obtained via combustion synthesis

In this work thermoluminescent properties of α-Al2O3 samples doped with Tb3+ and Tm3+, prepared by the combustion synthesis route, were studied. Samples were prepared by mixing stoichiometric amounts of aluminum nitrate, urea and dopants with different amounts of terbium and thulium nitrates varying from 0 to 0.15 mol%. The mixture was ignited in a muffle furnace at low temperature (500 °C). After the combustion, the samples were sintered at 1400 °C for 4 h in order to obtain the pure α-phase crystalline structure. The TL response of these samples for Co-60 gamma radiation was evaluated. It was observed a TL glow peak around 220 °C and a linear response for doses in studied range of 0.1–1 Gy. It was observed that the 0.1 mol% concentrations of both dopants present the highest TL sensitivity. The sensitivity of the co-doped (0.10 mol%) samples is 5 times higher than the 0.1 mol% Tm-only doped Al2O3 and 40 times higher than the sample doped only with 0.1 mol% of Tb. These results strongly suggest that the Al2O3:Tm–Tb, prepared through the combustion method, is a potential material for TL radiation dosimetry.

Luminescent properties of Ba3(PO4)2:Eu, Tb phosphors

AbstractLuminescence of europium (III), europium(II) and terbium(III) has been observed in Ba3(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.

High-pressure liquid chromatography of trace elements: Determination of terbium in terbium doped gadolinium oxide sulphide phosphors

A detailed study of isocratic and gradient elution separations of lanthanides has been carried out. Analyses of industrially and scientifically interesting products such as luminescent phosphors have been carried out by gradient elution with DL-2-hydroxyisobutyric acid. The determination of small amounts of terbium in gadolinium oxide sulphide phosphors is described in which an HCl solution was eluted through a stainless steel column packed with microparticulate silica, with bonded cation-exchange groups. Complete separation of gadolinium and terbium is achieved. Detection is with a variable wavelength detector following post-column complex formation with 4-(2-pyridylazo)-resorcinol monosodium salt. Results obtained on test solutions show good reproducibility and sensitivity and the method may be considered sufficiently reliable to be used in routine quality control procedures.