Sökning: "platina"

Visar resultat 1 - 5 av 33 avhandlingar innehållade ordet platina.

  1. 1. Evaluating Cathode Catalysts in the Polymer Electrolyte Fuel Cell

    Författare :Henrik Ekström; Göran Lindbergh; Anders Lundblad; Anthony Kucernak; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fuel cell; humidity; model electrodes; Nafion; oxygen reduction; PEMFC; platinum; polymer electrolyte; thin film evaporation; titanium oxide; bränslecell; fuktighet; modellelektroder; Nafion; PEMFC; platina; polymerelektrolyt; syrereduktion; tunnfilmsförångning; titanoxid; Electrochemistry; Elektrokemi;

    Sammanfattning : The polymer electrolyte membrane fuel cell (PEMFC) converts the chemical energy of hydrogen and oxygen (air) into usable electrical energy. At the cathode (the positive electrode), a considerable amount of platinum is generally required to catalyse the sluggish oxygen reduction reaction (ORR). LÄS MER

  3. 2. Advances in analytical methodologies for studies of the platinum metallome in malignant cells exposed to cisplatin

    Författare :Yvonne Nygren; Erik Björn; Knut Irgum; Bente Gammelgaard; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Method development; Metallome; Inductively coupled plasma mass spectrometry; Electrospray ionization mass spectrometry; Liquid chromatography; Hyphenation; Organic modifier; Cisplatin; Platinum; Analytical chemistry; Analytisk kemi; analytisk kemi; Analytical Chemistry;

    Sammanfattning : The scientific progress about the important chemotherapeutic drug substance cisplatin (CDDP) and its function has often been rendered by data difficult to interpret, and still many questions about its mode of action remains to be clarified by the scientific community. However, studies of CDDP possess a high complexity due to; i) low intracellular concentration, ii) many potential biomolecule targets, iii) poor or unknown stability of the intact drug and its biomolecule adducts and iv) complex and varying sample matrices. 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. Reactions of Model and Anticancer Active Platinum(IV/II) Complexes - A Kinetic and Mechanistic Study

    Författare :Kelemu Lemma; Kemiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Model Pt II complexes; Anticancer active Pt IV compounds; Cisplatin; Rescue agents; L-Ascorbic acid; Thiol; Substitution; Kinetics and mechanism; Electron transfer; Inorganic chemistry; Oorganisk kemi;

    Sammanfattning : In this thesis reductions of model and anticancer active Pt(IV) complexes with thiols and ascorbic acid and substitution reactions of cisplatin and model Pt(II) complexes with S-donor nucleophiles (rescue agents) have been investigated using stopped-flow and UV/VIS spectrophotometry. Glutathione (GSH) reduction of the anticancer active Pt(IV) compounds t- and c-[PtCl4(cha)(NH3)] (cha = cyclohexylamine), t-[PtCl4(thiazole)(NH3)] and c-[PtCl4(NH3)2] at 25 oC was observed to be very fast. LÄS MER

  7. 5. The many-electron energy in density functional theory : from exchange-correlation functional design to applied electronic structure calculations

    Författare :Rickard Armiento; Göran Grimvall; Jens K. Nörskov; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

    Sammanfattning : Att förutsäga egenskaper hos material och kemiska system är en viktig komponent för teoretisk och teknisk utveckling i fysik, kemi och biologi. Ett systems egenskaper styrs till stor del av dess elektrontillstånd. Datorprogram som baseras på täthetsfunktionalsteori kan beskriva elektronkonfigurationer mycket noggrant. LÄS MER