Search results for "europium"
showing 10 items of 112 documents
Luminescence Properties and Decay Kinetics of Mn2+ and Eu3+ Co-Dopant Ions In MgGa2O4 Ceramics
2018
A. Luchechko gratefully acknowledges a grant from the Institute of Physics PAS for a research visit to the institute, while A.I. Popov has been supported by project LZP-2018/1-0214 from the Latvian Council of Science.
Ground-state hyperfine-structure measurements of unstableEu+isotopes in a Paul ion trap
1997
Hyperfine separations in unstable ${\mathrm{Eu}}^{+}$ ions of mass 148, 149, and 150 have been measured in laser-microwave double-resonance experiments in a Paul ion trap. In spite of the small available quantities of the isotopes, the experimental uncertainties are of the order of ${10}^{\ensuremath{-}8}$ or below, which is of the same order as in earlier measurements on stable isotopes of ${\mathrm{Eu}}^{+}.$ Extensive second-order perturbation calculation is required to obtain coupling constants for magnetic-dipole $(A)$ and electric-quadrupole $(B)$ interactions. The uncertainties are a few times ${10}^{\ensuremath{-}7}$ for $A$ and ${10}^{\ensuremath{-}3}$ for $B.$ The experiments are …
Low-lying levels of201Hg from the decay of201Au
1972
The decay of 26.4-min201Au has been investigated using chemically separated sources and Ge(Li), Si(Li), plastic and Nal(Tl) detectors in different singles and coincidence arrangements. The β-disintegration energy was measured to be 1.27 ± 0.10 MeV. Thirteen γ-rays were observed to belong to this decay and the new levels at 543, 549.2, 552.8, 559.1, 605.7, 645.4, 732 and 1188 keV were established in201Hg, in addition to the three previously known excited states below 200 keV.
Levels in208Pb populated in the decay of208Tl(ThC″)
1969
Gamma rays in the disintegration of208Tl(ThC″) have been studied with Ge(Li)-Na I(Tl) anti-Compton and coincidence spectrometers. Several new transitions are reported most of which are placed in a decay scheme incorporating excited states in208Pb at 2,614.5, 3,197.6, 3,475.0, 3,708.3, 3,919.8, 3,960.9, 3,998.5, 4,125.3, 4,180.4, 4,296.1 and 4,480.0 keV. According to the present data, the recently reported intensity of 4.5±1.5% of beta groups feeding levels near 4.3 MeV is far too large.
Luminescence of Eu3+-doped lanthanum titanate (La2TiO5), a system with one-dimensional energy migration
1992
Abstract The titanate and Eu 3+ luminescence of a composition La 2 TiO 5 -Eu are reported as a function of temperature. At 4.2 K the quantum efficiency is very high, because the titanate excitation energy is localized. At 300 K there is delocalization and quenching centres are easily reached, so that the quantum efficiency becomes low. This is discussed in terms of the crystal structure, as are the peculiarities of the Eu 3+ spectra.
Electron paramagnetic resonance of doped and undoped BaFBr detected by recombination luminescence
1998
Abstract The recombination processes in the X-ray storage phosphor BaFBr:Eu2+ was investigated by measuring the microwave-induced changes in the recombination luminescence in a (high) magnetic field. Besides the resonances of the F(Br−) centre, of the VK(Br−2) centre and of the Eu2+ ground state we observed a line of a hitherto unknown hole centre. The maximum of the luminescence band in which the VK(Br−2) centre could be detected was about 400 nm. The resonance of the unknown hole centre belongs to a luminescence band peaking at about 350 nm.
RbBr and CsBr doped with Eu2+ as new competitive X-ray storage phosphors
2001
Abstract After X-irradiation of the alkali halides RbBr and CsBr doped with divalent Eu a significant photostimulated luminescence (PSL) effect was found. In both systems the electron trap centre is an F centre, the hole trap centre is still unknown. The Eu 2+ aggregation with cation vacancies plays an important role. Although all of the different Eu 2+ aggregates seem to show PSL effects, they have different PSL efficiencies, decay times and spectral characteristics. In the case of RbBr:Eu 2+ it was possible to investigate the different Eu 2+ -cation vacancy aggregate states by magnetic circular dichroism of the optical absorption (MCDA) and MCDA-detected electron paramagnetic resonance. I…
Trap Spectroscopy by the Glow Rate Technique using Bleaching of Colour Centres
2002
An application of the glow rate technique (GRT) for analysis of the parameters of thermostimulated decay of colour centres is presented using the data on the decay of radiation defects in LiBaF 3 :Fe crystals created by X rays at 300 K. The GRT offers a procedure for evaluation of the mean activation energy as a function of temperature in the case of arbitrary thermostimulated relaxation kinetics represented by the trap distribution function. The experimental procedure involves at least two subsequent measurements of thermostimulated decay kinetics at different heating rates. It is shown that the decay of the F type centres is governed by interaction of mobile anion vacancies with F A and F…
Facile approaches to build ordered amphiphilic tris(phthalocyaninato) europium triple-decker complex thin films and their comparative performances in…
2010
Solution processed thin films of an amphiphilic tris(phthalocyaninato) rare earth triple-decker complex, Eu(2)[Pc(15C5)(4)](2)[Pc(OC(10)H(21))(8)], have been prepared from three different methods: self-assembly (SA) annealed in solvent vapor, quasi-Langmuir-Shäfer (QLS) and drop casting methods. In particular, we successfully developed a simple QLS process for fabricating ordered multilayers with a good thickness control. The films prepared from three different methods were characterized by a wide range of methods including electronic absorption spectra, IR, X-ray diffraction, atomic force microscopy (AFM), and current-voltage (I-V) measurements. J-type aggregates have been formed with the …
Thermal and spectroscopic investigation of europium and samarium sulphates hydrates by TG-FTIR and ICP-MS techniques.
2005
The investigation of europium(III) sulphate hydrate and samarium(III) sulphate hydrate was performed by thermal analysis (TG-DTG) and simultaneous infrared evolved gas analysis-Fourier transformed infrared (EGA-FTIR) spectroscopy. The TG, DTG and DTA curves were recorded at the 25-1400 degrees C in the dynamic air atmosphere by TG/DTA analyser. The infrared evolved gas analysis was obtained on the FTIR spectrometer. Eu(2)(SO(4))(3).nH(2)O (n=3.97) and Sm(2)(SO(4))(3).nH(2)O (n=8.11) were analysed, the dehydration and decomposition steps were investigated and the water content was calculated. The formation of different oxysulphates was studied. The trace rare earth elements in Eu and Sm sulp…