Now showing items 356-375 of 1027

    • High Performance Triboelectric Nanogenerators from Compostable Cellulose-Biodegradable Poly(Butylene Succinate) Composites 

      Lapčinskis, Linards; Ģērmane, Līva; Platnieks, Oskars; Krikovs, Artis; Pudzs, Kaspars; Linarts, Artis; Sherrell, Peter C.; Šutka, Andris (Wiley, 2023)
      Triboelectric nanogenerator (TENG) devices are exemplar systems for mechanical-to-electrical energy conversion due to their simplicity and promising performance. However, little attention has been paid to recycling or ...
    • High power impulse magnetron sputtering of Zn/Al target in an Ar and Ar/O2 atmosphere: The study of sputtering process and AZO films 

      Zubkins, Martins; Arslan, H.; Bikse, Liga; Purans, Juris (Elsevier B.V., 2019)
      Reactive high power impulse magnetron sputtering (R-HiPIMS) has been demonstrated as a promising technique for the ZnO:Al (AZO) thin film deposition at low temperature with improved electrical properties compared to the ...
    • High resolution luminescence spectroscopy and thermoluminescence of different size LaPO4:Eu3+ nanoparticles 

      Gavrilović, Tamara; Laganovska, Katrīna; Zolotarjovs, Aleksejs; Smits, Krisjanis; Jovanović, Dragana J.; Dramićanin, Miroslav D. (Elsevier B.V., 2018)
      Nanoparticles (5 nm) and nanorods (2 nm × 15 nm and 4 nm × 20 nm) of monoclinic monazite LaPO4:Eu3+ were prepared by reverse micelle and co-precipitation techniques. Effects of the particle size and surface defects on the ...
    • High-order harmonics generation in Cd and Pd laser-induced plasmas 

      Ganeev, Rashid A.; Kim, Vyacheslav V.; Butikova, Jelena; Atvars, Aigars; Grube, Jurgis; Sarakovskis, Anatolijs; Ubelis, Arnolds (Optica Publishing Group, 2023)
      We demonstrate the generation of high-order harmonics of laser pulses in palladium and cadmium plasmas. We adjusted the wavelength of driving pulses to investigate the resonance enhancement in different ranges of extreme ...
    • High-pressure synthesis of boron-rich chalcogenides B12S and B12Se 

      Cherednichenko, Kirill A.; Mukhanov, Vladimir A.; Kalinko, Aleksandr; Solozhenko, Vladimir L. (Elsevier, 2022)
      Two boron-rich chalcogenides B12S and B12Se isostructural to α-rhombohedral boron were synthesized by chemical reaction of the elements at high-pressure – high-temperature conditions. The crystal structures and stoichiometries ...
    • High-Quality Si-Doped β-Ga2O3 Films on Sapphire Fabricated by Pulsed Laser Deposition 

      Khartsev, Sergey I.; Nordell, Nils; Hammar, Mattias; Purans, Juris; Hállen, Anderson (Wiley-VCH Verlag, 2020)
      Pulsed laser ablation is used to form high-quality silicon-doped β-Ga2O3 films on sapphire by alternatively depositing Ga2O3 and Si from two separate sources. X-ray analysis reveals a single crystallinity with a full width ...
    • High-temperature X-ray absorption spectroscopy study of thermochromic copper molybdate 

      Jonane, Inga; Anspoks, Andris; Aquilanti, Giuliana; Kuzmin, Alexei (Acta Materialia Inc, 2019)
      X-ray absorption spectroscopy at the Cu and Mo K-edges was used to study the effect of heating on the local atomic structure and dynamics in copper molybdate (α-CuMoO4) in the temperature range from 296 to 973 K. The reverse ...
    • Homme 

      Timuška, Agris (Editura Universităţii din Bucureşti, 2014)
    • How to draw combinatorial maps? 

      Zeps, Dainis; Ķikusts, Paulis (2013-01-31)
      In this article we consider the combinatorial map (rendered by permutations) approach to graphs on surfaces and how between both could be establish some terminological uniformity in favor of combinatorial maps in the way ...
    • Human Soul, Body and Life Horizons 

      Kūle, Maija (Springer, 2014)
    • Hybrid density functional calculations of hyperfine coupling tensor for hole-type defects in MgAl2O4 

      Platonenko, Alexander; Gryaznov, Denis; Kotomin, Eugene A.; Lushchik, Aleksandr; Seeman, Viktor; Popov, Anatoli I. (Elsevier B.V., 2020)
      We have performed the density functional calculations (DFT) on the hole-type defects (V-centres) in magnesium aluminate spinel (MgAl2O4) following the results of recent paramagnetic resonance measurements (EPR) in Nucl. ...
    • Hybrid Tribo-Piezo-Electric Nanogenerator with Unprecedented Performance Based on Ferroelectric Composite Contacting Layers 

      Lapčinskis, Linards; Mālnieks, Kaspars; Linarts, Artis; Blūms, Juris; Šmits, Krišjānis; Järvekülg, Martin; Knite, Māris; Šutka, Andris (American Chemical Society, 2019)
      It was recently reported that more efficient triboelectric nanogenerator (TENG)-like devices can be prepared using inversely polarized ferroelectric films made of same material as the contacting layers. In the present work, ...
    • Hydrogen from industrial aluminium scraps: Hydrolysis under various conditions, modelling of pH behaviour and analysis of reaction by-product 

      Urbonavicius, Marius; Varnagiris, Sarunas; Mezulis, Ansis; Lesnicenoks, Peteris; Knoks, Ainars; Richter, Christiaan; Milcius, Darius; Meirbekova, Rauan; Gunnarsson, Gudmundur; Kleperis, Janis (Elsevier, 2023)
      The study explores the feasibility of utilizing aluminium scrap waste from the construction industry for hydrogen production via hydrolysis. Specifically, the study involves a primary analysis of aluminium scrap waste and ...
    • Hydrothermal Synthesis and Properties of Yb3+/Tm3+ Doped Sr2LaF7 Upconversion Nanoparticles 

      Milićević, Bojana; Periša, Jovana; Ristić, Zoran; Milenković, Katarina; Antić, Željka; Smits, Krisjanis; Kemere, Meldra; Vitols, Kaspars; Sarakovskis, Anatolijs; Dramićanin, Miroslav D. (MDPI, 2023)
      We report the procedure for hydrothermal synthesis of ultrasmall Yb3+/Tm3+ co-doped Sr2LaF7 (SLF) upconversion phosphors. These phosphors were synthesized by varying the concentrations of Yb3+ (x = 10, 15, 20, and 25 mol%) ...
    • Idejas un ieteikumi uzņēmuma nosaukšanai 

      Berra, Solvita (LU Latviešu valodas institūts, 2021)
      Bukletā ir sniegts pārskats par uzņēmumu nosaukumu veidiem (tieši, simboliskie un jauktie nosaukumi; triviāli un netriviāli nosaukumi, lokāli, globāli un glokāli nosaukumi) un lingvistiskās izveides stratēģijām un līdzekļiem ...
    • Identification of Active Sites for Oxygen Reduction Reaction on Nitrogen- and Sulfur-Codoped Carbon Catalysts 

      Villemson, Karl Markus; Kaare, Kätlin; Raudsepp, Ragle; Käämbre, Tanel; Šmits, Krišjānis; Wang, Pangpang; Kuzmin, Anton V.; Šutka, Andris; Shainyan, Bagrat A.; Kruusenberg, Ivar (American Chemical Society, 2019)
      Nitrogen- and sulfur-codoped carbon catalysts were prepared as electrocatalytic materials for the oxygen reduction reaction (ORR). Herein, we propose a novel and effective one-pot synthetic approach to prepare a NS-doped ...
    • Identifying iron-bearing nanoparticle precursor for thermal transformation into the highly active hematite photo-fenton catalyst 

      Šutka, Anna; Šutka, Andris; Vanags, Martinsh Š.; Spule, Arnita; Eglītis, Raivis; Vihodceva, Svetlana; Smits, Krisjanis; Tamm, Aile; Mežule, Linda (MDPI AG, 2020)
      The hematite photo-Fenton catalysis has attracted increasing attention because it offers strong oxidation of organic pollutants under visible light at neutral pH. In the present work, aqueous synthesis of hematite photo-Fenton ...
    • Identitāte un citādība 

      Lapinska, Ieva (LU Filozofijas un socioloģijas institūts, 2012)
    • Identitāte un citādība 

      Lapinska, Ieva (LU Filozofijas un socioloģijas institūts, 2012)
      Grāmatā apkopoti latviešu filozofes un tulkotājas Ievas Lapinskas (1974-2010) darbi, tostarp līdz šim nepublicētais promocijas darba "Attiecību ar citādo izpratne mūsdienu filozofijā: Emanuēls Levins un Lisa Irigaraja" ...
    • Imanuels Kants - pasaules pilsonis no Kēnigsbergas 

      Hefe, Otfrīds (LU Filozofijas un socioloģijas institūts, 2011)
      Grāmatā publicētas divas ievērojamā vācu filosofa Otfrīda hefes lekcijas - "Imanuels Kants – pasaules pilsonis no Kēnigsbergas" un "Pašdomāšana. Imanuela Kanta „Atbilde uz jautājumu: kas ir apgaismība?”", kā arī Hefes ...