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Chemical Durability of Uranium Oxide Containing Glasses

Abstract

ZrO2 doped Na-Ba-borosilicate glasses suitable as matrix materials for HLW immobilization were synthesized and corrosion behaviour was investigated in different aqueous media. Hydrolytic stability is increased with the doping level until 5 mol %; above this value the glass vitrification tendency is strongly intensified. Unexpectedly, ZrO2 doping diminished the corrosion stability in 1M HCl solution, and low ZrO2 content showed a low corrosion resistance in 1M Na2CO3 solution also. Doping effect was negligible in case of synthetic seawater. The glass structure is significantly stabilized by the integration of the 30% UO3 added.

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A DFT study of the effects of Sc doping on electronic and optical properties of CdS nanoparticles

Abstract

In the present work a systematic study was carried out to understand the influence of Sc doping on electronic and optical properties of CdS nanoparticles. The geometry optimization and symmetry computation for CdS and Sc doped CdS nanoparticles using Density Functional Theory (DFT) on B3LYP level with the QZ4P for Cd and DZ2P for sulphur and Sc were performed by Amsterdam Density Functional (ADF). The results show that HOMO-LUMO gap as well as electronic and optical properties of CdS clusters vary with Sc doping. The HOMO-LUMO gap is affected by the dopant and its value decreases to 0.6 eV. Through considering the numerical integration scheme in the ADF package, we investigated different vibrational modes and our calculated Raman and IR spectra are consistent with the reported result. The calculated IR and Raman peaks of CdS and Sc doped CdS clusters were in the range of 100 to 289 cm−1, 60 cm−1 to 350 cm−1 and 99 cm−1 to 282 cm−1, 60 cm−1 to 350 cm−1, respectively, which was also confirmed by experiment as well as a blue shift occurrence. Subsequently, for deeper research of pure and doped CdS clusters, their absorption spectra were calculated using time-dependent DFT method.

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Investigation of optical properties of silicon oxynitride films deposited by RF PECVD method

carry out the measurements at different incidence angles (65°, 70°, 75°). The parameters were calculated for wavelength ranging from 300 to 1000 nm with the measurement resolution of 10 nm. The reflection coefficient of the SiO x N > y /SiO 2 bilayer was measured in a system with integrating sphere. 3 Results The measurements were carried out in order to perform calibration of PECVD process and characterization of optical properties of the manufactured SiO x N y films. From the measured thickness of the deposited film, the growth rate of the film was

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Inkjet-printed flexible RFID antenna for UHF RFID transponders

contactless identification of various objects. It is applied in different areas of everyday life – in the industry, trade, security and in almost all other socioe-conomic spheres – where applied RFID components have to meet various technological, environmental and, above all, low-cost requirements. It is due to the need of integrating RFID transponders with various objects that are characterized by miscellaneous physical properties. Therefore, flexible electronic devices are the most suitable for marking consumer goods, materials and components in production, personal

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Characteristics of TlBr single crystals grown using the vertical Bridgman-Stockbarger method for semiconductor-based radiation detector applications

300, Agilent Technologies, Co.) equipped with an integrating sphere within the wavelength range of 200 nm to 800 nm. The current-voltage (I-V) characteristics of the samples were measured with a parameter analyzer (4200SCS, Keithley). Before measuring the I-V data, 300 Å thick gold-contacts were evaporated on both sides of the samples. 4 Results Fig. 2 and Table 1 show the ICP-MS results for the raw material used, and the top, middle, and bottom samples of TlBr. It should be noted that the concentrations of the major impurity elements observed in the

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Electronic structure and optical properties of (BeTe)n/(ZnSe)m superlattices

one-particle Schrödinger equation (at fixed energy), and their energy derivatives are multiplied by spherical harmonics. We have used the recently developed LmtART package (LmtART 7) with the electrons exchange-correlation energy described using the Perdew-Wang parameterization of the local density approximation (LDA) [ 10 ]. The details of the calculations are as follows: the charge density and the potential are represented inside the muffin-tin sphere (MTS) spherical harmonics up to l max = 6. The k integration over the Brillouin zone is performed using the

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Electronic and structural properties of rare earth pnictides

electronegativity criteria [18] . The partial waves of s p d and f states were taken into account. The E and k convergences were checked subsequently to achieve better accuracy. The calculations were performed for 512 k points (the grid of 8 × 8 × 8) in the Brillouin zone for both the B1 and B2 phases. To obtain the total energy and partial density of states the tetrahedron method of Brillouin zone integration was used [19] . The total energy was computed by reducing the volume from 1.05 V 0 to 0.60 V 0 , where V 0 is an equilibrium cell volume. The calculated total energy

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Investigations of optical and surface properties of Ag single thin film coating as semitransparent heat reflective mirror

using a coupled DH-2000-BAL deuterium-halogen lamp as an excitation light source, 30 mm integration sphere and two Ocean Optics spectrophotometers: QE65000 type for 200–900 nm range and NIR 256-2.1 type for 900–2100 nm range. Quartz-halogen lamp was used to generate heat radiation and the samples were exposed from the distance of 300 mm. Temperature of the samples during exposition to heat was controlled by standard K-type thermocouples and it was recorded over the exposition time using Agilent 34970A unit equipped with Agilent 34901A 20 channel multiplexer. The

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Effect of TEA on characteristics of CdS/PbS thin film solar cells prepared by CBD

for energy production. Integration of nanostructured materials in photovoltaic devices has been demonstrated to open the possibilities to develop low-cost solar cells. Because of their fundamental structural, electrical and optical properties resulting from quantum confinement, nanocrystalline inorganic materials have been widely studied for solar cell application [ 1 ]. PbS is a unique semiconductor material with a small band gap (0.41 eV at 300 K) and large bulk exciton Bohr radius (18 nm). This band gap can be easily manipulated by altering the semiconductor

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Electronic and optical properties of Mn–S co-doped anatase TiO2 from first-principles calculations

300 eV for all the computations. The special points sampling integration over the Brillouin zone was carried out using the Monkhorst-Pack method with a 2 × 2 × 2 special-point mesh. All of the structures were allowed to relax using the Broyden-Fletcher-Goldfarb-Shanno (BFGS) quasi-Newton scheme with the convergence threshold for the maximum energy change of 2.0 × 10 -5 eV/atom, and the maximum force, maximum stress and maximum displacement tolerances set as 0.05 eV/Å, 0.1 GPa, and 0.002 Å, respectively. These parameters are sufficient for well-converged total

Open access