Browsing Zinātniskie raksti (CFI) / Scientific articles by Title
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Comparative Study on Micromechanical Properties of ZnO:Ga and ZnO:In Luminiscent Ceramics
(De Gruyter, 2021)Indium (0.038 at.%) and gallium (0.042 at.%) doped ZnO ceramics were prepared by hot pressing. Ceramics were investigated to determine their structural and mechanical characteristics for the prospective use in scintillators. ... -
Comparison of LIBS results on ITER-relevant samples obtained by nanosecond and picosecond lasers
(Elsevier Ltd, 2019)ITER foresees applying laser induced breakdown spectroscopy (LIBS) as a tool for quantitative assessment of fuel retention in the first walls. One open problem related to LIBS application is the choice of the laser type. ... -
Comparison of Luminescence in LiGaO2, Al2 O3 -Ga and Al2 O3 -Li Crystals
(Sciendo, 2018)We have studied luminescence of LiGaO 2 , Al 2 O 3 -Ga and Al 2 O 3 -Li crystals in order to reveal the nature of luminescence centres and mechanisms in these crystals. In Al 2 O 3 -Ga presence of Ga impurities determines ... -
Complex multilayer carbon structures for green energetics
(Estonian Academy Publishers, 2017)We investigated a promising material for hydrogen storage and sensing. The material was obtained by exfoliating recycled graphite waste and simultaneously modifying the product with metal impurities (Bi, V, Cu). As a ... -
Composite material recycling technology—state-of-the-art and sustainable development for the 2020s
(Multidisciplinary Digital Publishing Institute (MDPI), 2021)Recently, significant events took place that added immensely to the sociotechnical pressure for developing sustainable composite recycling solutions, namely (1) a ban on composite landfilling in Germany in 2009, (2) the ... -
Composite membranes of sulfonated poly (Ether ether ketone) with active carbon: Composite preparation and investigation of their properties for potential application for co2 electrochemical reduction
(Kauno Technologijos Universitetas, 2020)In this study, synthesis of sulfonated poly(ether ether ketone) (SPEEK) was performed using sulfonation method with concentrated sulfuric acid. Polymer with three degrees of sulfonation was obtained: 0.87; 0.82 and 0.74. ... -
Computer Simulation of the Electric Transport Properties of the FeSe Monolayer
(Walter de Gruyter, 2020)The paper deals with the model research of electric transport characteristics of stressed and non-stressed FeSe monolayers. Transmission spectra, current-voltage characteristic (CVC) and differential conductivity spectra ... -
Computer Simulation to Optimize the VFA Alpha Prototype with a Hydraulic Piston Compressor and an Integrated Booster
(Sciendo, 2020)Natural gas, including biomethane, is a sustainable alternative fuel. Widening compressed natural gas applications by now is restricted by weakly developed infrastructure. Hygen Ltd. works on "hydraulic piston"technology ... -
Computer Simulations of the Band Structure and Density of States of the Linear Chains of NaCl Ions
(Sciendo, 2019)The paper presents the results of first-principles computer simulations of the band structure, the density of states, and the total energy of NaCl (NaCl, Na2Cl2, Na3Cl3, Na4Cl4, Na6Cl6) linear chains of atoms. Modelling ... -
Contribution of molecular structure to self-assembling and biological properties of bifunctional lipid-like 4-(N-alkylpyridinium)-1,4-Dihydropyridines
(MDPI AG, 2019)The design of nanoparticle delivery materials possessing biological activities is an attractive strategy for the development of various therapies. In this study, 11 cationic amphiphilic 4-(N-alkylpyridinium)-1,4-dihydropyridine ... -
Control of Strongly Nonequilibrium Coherently Correlated States and Superconducting Transition Temperature
(MDPI, 2023)Our paper considers the possibility of the emergence and control of non-equilibrium states of a quasi-homogenous condensed medium with energy and particle flows in the phase space, which, first of all, manifest themselves ... -
Core–Shell Engineering to Enhance the Spectral Stability of Heterogeneous Luminescent Nanofluids
(Wiley-VCH Verlag, 2017)The tendency to the miniaturization of devices and the peculiar properties of the nanoparticles have raised the interest of the scientific community in nanoscience. In particular, those systems consisting of nanoparticles ... -
Corrigendum to Evaluation of radiation stability of electron beam irradiated Nafion® and sulfonated poly(ether ether ketone) membranes
(Elsevier, 2022)Proton exchange membranes (PEM), which have been commonly used in fuel cells have raised interest for the application in harsh environments involving ionizing radiation. Therefore, radiation stability and ability to sustain ... -
Creation of glass-characteristic point defects in crystalline SiO2 by 2.5 MeV electrons and by fast neutrons
(Elsevier B.V., 2019)Point defects in crystalline SiO2, created by 2.5 MeV electron irradiation at dose below the amorphization threshold or by fast neutrons, were compared by luminescence spectroscopy. Oxygen dangling bonds (“non-bridging ... -
Critical Evaluation of the Methods for the Characterization of the Degree of Sulfonation for Electron Beam Irradiated and Non-Irradiated Sulfonated Poly(ether ether ketone) Membranes
(MDPI, 2023)Sulfonated poly(ether ether ketone) (SPEEK) materials are promising candidates for replacing Nafion™ in applications such as proton exchange membrane (PEM) and direct methanol fuel cells. SPEEK membranes have several ... -
Critical review on experimental and theoretical studies of elastic properties of wurtzite-structured ZnO nanowires
(De Gruyter, 2023)In this critical review, we call attention to a widespread problem related to the vast disagreement in elastic moduli values reported by different authors for nanostructures made of the same material. As a particular ... -
Crystalline phase detection in glass ceramics by EPR spectroscopy
(AIP Publishing, 2018)The advances of EPR spectroscopy for the detection of activators as well as determining their local structure in the crystalline phase of glass ceramics is considered. The feasibility of d-element (Mn2+, Cu2+) and f-element ... -
Cubic and rhombohedral Ba4Lu3F17:Er3+ in transparent glass ceramics: Crystallization and upconversion luminescence
(Elsevier B.V., 2018)Novel Er3+ doped glass ceramics containing Ba4Lu3F17 nanocrystals were successfully prepared by heat treatment of melt-quenched glasses. Highly efficient upconversion luminescence was detected under near-infrared excitation ... -
Depth profiles of aggregate centers and nanodefects in LiF crystals irradiated with 34 MeV 84Kr, 56 MeV 40Ar and 12 MeV 12C ions
(Elsevier B.V., 2018)Depth profiles of nanohardness and photoluminescence of F2 and F3 + centers in LiF crystals irradiated with 12 MeV 12C, 56 MeV 40Ar and 34 MeV 84Kr ions at fluences 1010–1015 ions/cm2 have been studied using laser scanning ... -
Depth profiles of damage creation and hardening in MgO irradiated with GeV heavy ions
(Elsevier B.V., 2019)The effect of irradiation with GeV heavy ions (U, Au, Bi) on the structure and mechanical properties of MgO single crystals was studied. The methods of nanoindentation, dislocation mobility, optical absorption and ...