Browsing Zinātniskie raksti (CFI) / Scientific articles by Title
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Octahedral Tilting in Homologous Perovskite Series CaMoO3-SrMoO3-BaMoO3 Probed by Temperature-Dependent EXAFS Spectroscopy
(MDPI, 2022)Local distortions in perovskites can be induced by cation displacements and/or by the tilting and rotating of cation–anion octahedra. Both phenomena have been subject to intense investigations over many years. However, ... -
ODS ferritic steels obtained from gas atomized powders through the STARS processing route: Reactive synthesis as an alternative to mechanical alloying
(Elsevier Ltd, 2018)Oxide Dispersion Strengthened Ferritic Stainless Steels (ODS FS) are candidate materials for structural components in fusion reactors. Their ultrafine microstructure and the presence of a very stable dispersion of Y-Ti-O ... -
On low-temperature luminescence quenching in Gd3(Ga,Al)5O12:Ce crystals
(Elsevier B.V., 2019)Temperature dependences of the photoluminescence and X-ray excited luminescence intensity and thermally stimulated luminescence glow curves are measured in the 4.2–300 K temperature range for the undoped and Ce3+ - doped ... -
On the Heuristic Procedure to Determine Processing Parameters in Additive Manufacturing based on Materials Extrusion
(MDPI AG, 2020)We present a heuristic procedure for determining key processing parameters (PPs) in materials-extrusion-based additive manufacturing processes. The concept relies on a design-of-experiment approach and consists of eleven ... -
On the Symmetry, Electronic Properties, and Possible Metallic States in NASICON-Structured A4V2(PO4)3 (A = Li, Na, K) Phosphates
(2023)In this work, the electronic structure and properties of NASICON-structured A4V2(PO4)3, where A = Li, Na, K were studied using hybrid density functional theory calculations. The symmetries were analyzed using a group ... -
On the Way to Optoionics
(Wiley Blackwell, 2020)Based on the recent finding of significant ion conduction enhancement in iodide perovskites upon illumination, the potential of an emerging field ‘opto-ionics’ – that we define in parallelism to ‘opto-electronics’ – is ... -
Optical Characteristics of MgAl2O4 Single Crystals Irradiated by 220 MeV Xe Ions
(MDPI, 2023)In In this study, the optical properties of magnesium-aluminate spinel were examined after being irradiated with 220 MeV Xe ions. The research aimed to simulate the impact of nuclear fuel fission fragments on the material. ... -
Optical detection of paramagnetic centres in activated oxyfluoride glass-ceramics
(Polish Academy of Sciences, 2018)Electron paramagnetic resonance (EPR), magnetic circular dichroism (MCD) and EPR detected via MCD (MCD-EPR) investigations have been performed on rare-earth activated oxyfluoride glasses and glass-ceramics. Er3+, Gd3+, and ... -
Optical properties and structure particularities of LiNbO3 crystals grown from a boron-doped melt
(Taylor and Francis Ltd., 2019)A series of LiNbO3:B crystals was grown from the melt doped by boron. It is shown that LiNbO3:B crystals possess an increased resistance to optical damage. We have found changes according to Raman spectra confirming the ... -
Optical properties of powder and ceramics of aluminium oxynitride obtained by self-propagating high-temperature synthesis
(Lithuanian Physical Society, 2021)The synthesis method of aluminium oxynitride (AlON) powders by nitriding of Al/Al2 O3 mixture under high-pressure nitrogen is proposed. The novelty of this method consists in adding KClO4 or Mg(ClO4 )2 and extra Al into ... -
Optimization of gyrotron resonator’s dimensions
(National Institute of Telecommunications, 2021)This paper explains the procedure of determining the initial dimensions of a gyrotron resonator. In particular, the paper discusses which geometrical parameters impact the wave properties of the resonator. The solution is ... -
Ordering of fluorite-type phases in erbium-doped oxyfluoride glass ceramics
(Elsevier B.V., 2018)In this study, novel transparent Er3+ doped glass ceramics were prepared from melt-quenched oxyfluoride glasses with general composition of Na2O-NaF-BaF2-YbF3-Al2O3-SiO2. The crystallization of fluorite (BaF2, BaF2-YbF3, ... -
Orientation of the electric field gradient and ellipticity of the magnetic cycloid in multiferroic BiFeO3
(Taylor and Francis Ltd., 2017)The paper deals with the hyperfine interactions observed on the 57Fe nucleus in multiferroic BiFeO3 by means of the 14.41-keV resonant transition in 57Fe and for transmission geometry applied to the random powder sample. ... -
Origin of Kerr effect: investigation of solutions by polarization dependent Z-scan
(Optical Society of America, 2020)The nonlinear refractive index dependence on the incident light polarization state has been studied for pure chloroform and chloroform solutions of aminobenziliden-1,3-indandione derivatives. Measurements were done with ... -
Origin of pressure-induced insulator-to-metal transition in the van der Waals compound FePS3 from first-principles calculations
(John Wiley and Sons Inc., 2020)Pressure-induced insulator-to-metal transition (IMT) has been studied in the van der Waals compound iron thiophosphate (FePS3) using first-principles calculations within the periodic linear combination of atomic orbitals ... -
Origin of Pressure-Induced Metallization in Cu3N: An X-ray Absorption Spectroscopy Study
(Wiley-VCH Verlag, 2018)High-pressure (0–26.7 GPa) Cu K-edge X-ray absorption spectroscopy is used to study possible structural modifications of anti-perovskite-type copper nitride (Cu3N) crystal lattice. The analysis of X-ray absorption near-edge ... -
ORR activity and stability of Co-N/C catalysts based on silicon carbide derived carbon and the impact of loading in acidic media
(Electrochemical Society Inc., 2018)A simple and facile synthesis method was used to produce two Co-N/C type oxygen reduction reaction (ORR) catalysts. The materials were initially characterized by utilizing a variety of physical methods. Most importantly, ... -
Overview of the Structural, Electronic and Optical Properties of the Cubic and Tetragonal Phases of PbTiO3 by Applying Hubbard Potential Correction
(MDPI, 2023)We have performed a systematic study resulting in detailed information on the structural, electronic and optical properties of the cubic (Pm (Formula presented.) m) and tetragonal (P4mm) phases of PbTiO3 applying the GGA/PBE ... -
Oxidation State and Local Structure of Chromium Ions in LaOCl
(MDPI, 2021)LaOCl doped with 0–10 mol% Cr was synthesized by thermal decomposition of chlorides. X-ray diffraction (XRD) analysis revealed that incorporation of chromium results in a decrease of the lattice parameter a and a simultaneous ... -
Oxygen evolution reaction on a N-doped Co0.5-terminated Co3O4 (001) surface
(De Gruyter, Latvian Academy of Sciences, 2020)Recent experimental findings suggest that the catalytic activity of Co3O4 for oxygen evolution reaction (OER) could be improved by nitrogen doping. We present preliminary OER modelling on a N-doped Co3O4 surface, with ...