Trivalent zirconium and hafnium ions in yttria-based transparent ceramics

Electron paramagnetic resonance spectra of transparent yttria-based ceramics with zirconium and hafnium additives contain signals with close parameters due to paramagnetic Zr3+ and Hf3+ ions, which have similar ground-state electron configurations of [Kr]4d 1 and [Xe]5d 1, respectively. © 2013 Pleiades Publishing, Ltd

Fabrication and characterization of 1, 5, 10 at.% Ce:Y2O3 nanopowders

Nanopowders (particle size of about 7-14 nm) of yttrium oxide doped with cerium ions with concentrations of 1, 5, 10 at.% have been synthesized by laser ablation of the target. For the first time in the world the cerium concentration of 10 at.% in the yttrium oxide lattice has been obtained. Their morphology, structure, and scintillation properties have been investigated. No significant cathodoluminescence of the activator in the Ce3+ state has been detected in the powders, and X-ray luminescence was completely absent. Presumably, the cerium ion is in the nonradiative state of Ce4+. © Published under licence by IOP Publishing Ltd.Russian Foundation for Basic Research, RFBR: 19-08-00117The reported study was funded by RFBR, project number 19-08-00117. The authors gratefully acknowledge E.V. Tihonov and Dr. A.I. Medvedev from Institute of Electrophysics UrB RAS for laser synthesis of nanopowders and XRD analysis, respectively

Precision determination of band offsets in strained InGaAs/GaAs quantum wells by C-V-profiling and Schroedinger-Poisson self-consistent simulation

The results of measurements and numerical simulation of charge carrier distribution and energy states in strained quantum wells In_xGa_{1-x}As/GaAs (0.06 < x < 0.29) by C-V-profiling are presented. Precise values of conduction band offsets for these pseudomorphic QWs have been obtained by means of self-consistent solution of Schroedinger and Poisson equations and following fitting to experimental data. For the conduction band offsets in strained In_xGa_{1-x}As/GaAs - QWs the expression DE_C(x) = 0.814x - 0.21x^2 has been obtained.Comment: 9 pages, 12 figures, RevTeX

Effect of the Polarizability of Organic Compounds on Isotherms of Sorption of Their Vapors with Solid tert-Butylcalix[4]arene

The stoichiometry and free energy of formation of saturated solid host-guest complexes were determined from the sorption isotherms of the vapors of organic compounds of various classes with solid tert-butylcalix[4]arene and from their limiting activity coefficients in toluene at 298 K. The contribution of the supramolecular effect to the free energy of formation of these complexes was estimated. The complexation stoichiometry and the observed supramolecular effect decrease with increasing molar refraction of the guest compound. The complexation stoihiometry is a step function of the molar refraction of the guest molecule

Influence of the guest molecular size on the thermodynamic parameters of host-guest complexes between solid tert-butylcalix[4]arene and vapours of organic compounds

The shape of guest molecules has a significantly greater influence on the free energy of supramolecular effect in the formation of solid complexes of tert-butylcalix[4]arene than on their stoichiometry

LUMINESCENT ANALYSIS OF PHASE COMPOSITION OF THE POWDER OF YTTRIUM OXIDE DOPED WITH NEODYMIUM (3+)

Phase composition of Nd3+Y20 3 nanopowders was investigated by luminescence methods. Dependence of spectra characteristics on phase composition of nanopowders was calculated on the basis of ratio o f integral characteristics of the cathodoluminescence spectra of nanopowders. This dependence can be used to determine the phase composition of powder by the cathodoluminescence spectra