Sökning: "tungsten-oxide"

Visar resultat 1 - 5 av 19 avhandlingar innehållade ordet tungsten-oxide.

1. 1. Dynamic and quasi-stationary electrochromic response of amorphous tungsten oxide thin films : In situ combined electrochemical and optical measurements during lithium intercalation

   Författare :Edgar Alonso Rojas González; Gunnar Niklasson; Aline Rougier; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electrochromism; Optical absorption; Amorphous materials; Tungsten oxide; Electrochemical impedance spectroscopy; Color impedance spectroscopy; Intercalation; Engineering Science with specialization in Solid State Physics; Teknisk fysik med inriktning mot fasta tillståndets fysik;

   Sammanfattning : Electrochromic (EC) materials can adjust their optical properties, reversibly, by means of an external electrical stimulus. They have relevant technological applications; for example, energy-efficient smart windows, which can adapt dynamically—according to the given environmental conditions—to control the heat and visible light fluxes between the interior and exterior of a building. LÄS MER

3. 2. Optical Absorption and Electrical Conductivity in Lithium Intercalated Amorphous Tungsten Oxide Films

   Författare :Lars Berggren; Gunnar A. Niklasson; Ola Hunderi; Uppsala universitet; []
   Nyckelord :Technology; Lithium intercalation; amorphous; tungsten-oxide; sputtered films; optical absorption; polaron radius.; TEKNIKVETENSKAP; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : Optical and electrical properties of electrochemically lithium ion intercalated thin films of x-ray amorphous tungsten oxide made by magnetron sputtering on glass substrates coated with a thin layer of conductive tin doped indium oxide, have been studied. The composition and the density of the films were characterized by the ion beam analysis methods Rutherford Backscattering Spectroscopy and Elastic Recoil Detection Analysis. LÄS MER

4. 3. Electrochemical Reactions in Polymer Electrolyte Fuel Cells

   Författare :Maria Wesselmark; Svein Sunde; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fuel cell; model electrodes; oxygen reduction; methanol oxidation; formic acid oxidation; hydrogen oxidation; CO oxidation; degradation; tungsten oxide; carbon support; Bränslecell; modellelektroder; syrgasreduktion; metanoloxidation; myrsyraoxidation; vätgasoxidation; CO oxidation; degradering; wolfram oxid; kolsupport; Chemical engineering; Kemiteknik;

   Sammanfattning : The polymer electrolyte fuel cell converts the chemical energy in a fuel, e.g. hydrogen or methanol, and oxygen into electrical energy. The high efficiency and the possibility to use fuel from renewable sources make them attractive as energy converters in future sustainable energy systems. LÄS MER

5. 4. Heterogeneous Photolytic Synthesis of Nanoparticles

   Författare :Oscar Alm; Klaus Piglmayer; Uppsala universitet; []
   Nyckelord :Chemistry; LCVD; Nanotechnology; Metallocene; Magnetic; Photolysis; OES; tungsten oxide; gas sensing; Kemi;

   Sammanfattning : Nanoparticles of iron, cobalt and tungsten oxide were synthesised by photolytic laser assisted chemical vapour deposition (LCVD). An excimer laser (operating at 193 nm) was used as an excitation source. The LCVD process, was monitored in situ by optical emission spectroscopy (OES). LÄS MER

7. 5. Aqueous Processing of WC-Co Powders Aqueous processing of WC-Co powders

   Författare :Karin Andersson; KTH; []
   Nyckelord :Hard metal; cemented carbide; WC-Co; tungsten oxide; tungsten carbide; oxidation; cobalt; dissolution; surface complexation; XPS; AFM; colloidal probe; force curve; Hamaker constant; Cauchy; WO3; CoOOH; CoO; Co3O4; ESCA; zeta-potential; surface poten;

   Sammanfattning : The object of this work is toobtain a fundamental understanding of the principal issuesconcerning the handling of WC-Co powders, in an aqueousmedium.The oxidation and dissolution oftungsten carbide powder dispersed in water was investigatedusing X-ray Photoelectron Spectroscopy (XPS) and leachingstudies. LÄS MER