Browsing Zinātniskie raksti (CFI) / Scientific articles by Issue Date
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Raman spectral identification of phase distribution in anodic titanium dioxide coating
(Estonian Academy of Sciences, 2017)Growing need for cleaner environment and energy production has brought about a hunt for perspective materials. One of such perspective materials is titanium dioxide (TiO2, titania) due to its chemical stability and ... -
Luminescence properties of chlorine molecules in glassy SiO2 and optical fibre waveguides
(Estonian Academy Publishers, 2017)Glassy SiO2 is the basic material for optical fibre waveguides and manufacturing-induced Cl impurities reduce their transparency in UV spectral range. This work reports in-depth study/spectroscopic parameters of the ... -
Polarization and acoustic properties of barium-modified lead-free potassium–sodium niobate ceramics
(Estonian Academy Publishers, 2017)Results of polarization and polarization switching in samples prepared by solid phase synthesis of the (1-х)(K0.5Na0.5)(Nb0.93Sb0.07)O3–xBaTiO3 + 0.5mol%MnO2 system at x = 0.01, 0.02, and 0.04 (KNNS7–xBT) studied over a ... -
First-principles calculations on Fe-Pt nanoclusters of various morphologies
(Nature Publishing Group, 2017)Bimetallic FePt nanoparticles with L1 0 structure are attracting a lot of attention due to their high magnetocrystalline anisotropy and high coercivity what makes them potential material for storage of ultra-high density ... -
Influence of the preparation method on planar perovskite CH3NH3PbI3-xClx solar cell performance and hysteresis
(De Gruyter Open Ltd, 2017)Organometal halide perovskites are promising materials for lowcost, high-efficiency solar cells. The method of perovskite layer deposition and the interfacial layers play an important role in determining the efficiency of ... -
Nitrogen adsorption on graphene sponges synthesized by annealing a mixture of nickel and carbon powders
(De Gruyter Open Ltd, 2017)Adsorption by graphene sponge (GS) manufactured by annealing nickel-carbon powder mixture in inert atmosphere has been studied. By determining the specific surface area (SSA) for the GS sample, it has been found that ... -
Structure, tritium depth profile and desorption from ‘plasma-facing’ beryllium materials of ITER-Like-Wall at JET
(Elsevier Ltd, 2017)Tritium depth profile and its temperature programmed desorption rate were determined for selected samples cut out of beryllium tiles removed from the Joint European Torus vacuum vessel during the 2012 shut down. A beryllium ... -
Behaviour of thermal expansion of (1-x)Pb(Ni1/3Nb2/3)O3–xPbTiO3 solid solutions
(Estonian Academy Publishers, 2017)The features of the dependence of the bulk coefficient of thermal expansion of the (1-x)Pb(Ni1/3Nb2/3)O3-xPbTiO3 solid solution studied in the series of x = 0-0.8 in the temperature range from 100 to 750 K are reported. ... -
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 ... -
Influence of uniaxial pressure on dielectric properties of (1-x)Na0.5Bi0.5TiO3–xSrTiO3 for x = 0.01, 0.04, and 0.1 ceramics
(Estonian Academy Publishers, 2017)The conventional solid-state sintering was applied to synthesized (1-x)Na0.5Bi0.5TiO3-xSrTiO3 (x = 0.01, 0.04, and 0.1) ceramics. Dielectric measurements of these ceramics were taken in the temperature range from 20 to 600 ... -
Thermal disorder and correlation effects in anti-perovskite-type copper nitride
(Elsevier Ltd, 2017)Reverse Monte Carlo simulations coupled with evolutionary algorithm were employed for the analysis of the temperature dependent (10–300 K) Cu K-edge extended X-ray absorption fine structure (EXAFS) spectra of polycrystalline ... -
Electric relaxation and Mn3+/Mn4+ charge transfer in Fe-doped Bi12MnO20–BiMn2O5 structural self-composite
(Springer New York LLC, 2017)Fe-doped Bi12MnO20–BiMn2O5 ceramics was sintered at 1130 K for 6 h in ambient air. Two centro-symmetric phases formed thermodynamically stable self-composite material that was deduced from X-ray pattern analysis. The lattice ... -
Luminescence of X-ray induced radiation defects in modified lithium orthosilicate pebbles with additions of titanium dioxide
(Lithuanian Academy of Sciences Publishers, 2017)Modified lithium orthosilicate (Li4SiO4) pebbles with additions of titanium dioxide (TiO2) are designed as a possible tritium breeder ceramic for the helium cooled pebble bed (HCPB) test blanket module. Additions of TiO2 ... -
Modified graphene sheet stacks for hydrogen binding
(Kauno Technologijos Universitetas, 2017)Graphene sheet stacks were obtained using electrochemical exfoliation method. The morphology, distribution of elements and structure of the obtained samples were investigated using scanning electron microscopy, energy ... -
Target transportation of auxin on mesoporous Au/SiO2 nanoparticles as a method for somaclonal variation increasing in flax (L. usitatissimum L.)
(Hindawi Limited, 2017)Development of methods for direct delivery of different bioactive substances into the cell is a promising and intensively approached area of research. It has become a subject of serious research for multidisciplinary team ... -
Doped zirconia phase and luminescence dependence on the nature of charge compensation
(Nature Publishing Group, 2017)Zirconia is a relatively new material with many promising practical applications in medical imaging, biolabeling, sensors, and other fields. In this study we have investigated lanthanide and niobium doped zirconia by ... -
Cavity Ring-Down Spectroscopy measurements of Acetone concentration
(Institute of Physics Publishing, 2017)The Cavity Ring-Down Spectroscopy system for medical applications is created and first results for detection of acetone are shown. The acetone concentration was measured in the air. In the system a pulsed 1 kHz 266 nm DPSS ... -
Certain doping concentrations caused half-metallic graphene
(Elsevier B.V., 2017)The singly B and N doped graphene systems are carefully studied. The highly concentrated dopants cause a spin polarization effect in the systems. The spin polarization limits are affirmed in the singly B and N doped graphene ... -
Colorimetric gas detection by the varying thickness of a thin film of ultrasmall PTSA-coated TiO2 nanoparticles on a Si substrate
(Beilstein-Institut Zur Forderung der Chemischen Wissenschaften, 2017)Colorimetric gas sensing is demonstrated by thin films based on ultrasmall TiO2 nanoparticles (NPs) on Si substrates. The NPs are bound into the film by p-toluenesulfonic acid (PTSA) and the film is made to absorb volatile ...