Sökning: "laser-flash photolysis"

Hittade 5 avhandlingar innehållade orden laser-flash photolysis.

  1. 1. Kinetics of proton and electron transfer in heme-copper oxidases

    Författare :Peter Lachmann; Pia Ädelroth; Örjan Hansson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Heme-copper oxidase; electron transfer; proton transfer; nitric oxide reductase; ba3 oxidase; flow-flash; laser-flash photolysis; Biochemistry; biokemi;

    Sammanfattning : Heme-copper oxidases are transmembrane proteins that are found in aerobic and anaerobic respiratory chains. During aerobic respiration, these enzymes reduce dioxygen to water. The energy released in the reaction is used to transport protons across a biological membrane. LÄS MER

  3. 2. Tuning electron transfer reactions by selective excitation in porphyrin-acceptor assemblies

    Författare :Mikael Andersson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik; Physical Chemistry; fysikalisk kemi;

    Sammanfattning : This thesis concerns electron transfer reactions from different excited states in porphyrins, and the effect of changing the energy of the link connecting the donor and acceptor. Photoinduced electron transfer, and subsequent processes were studied using ultrashort laser pulses and nanosecond laser flash photolysis. LÄS MER

  4. 3. Experimental and Theoretical Studies of Cis-Trans Photoisomerizations and Conditions for Effective Catalysis

    Författare :Helene Möllerstedt; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; catalysis; triplet state; quantum chain process; cis-trans isomerization; adiabatic; potential energy surface; density functional theory; energy transfer;

    Sammanfattning : Triplet-sensitized cis-trans photoisomerizations have been investigated both experimentally and theoretically. Mapping of the reaction path for isomerization of 1,4-bis(1-propenyl)benzene (1) on the triplet state energy surface has been done by quantum yield measurements and laser flash photolysis. LÄS MER

  5. 4. Synthesis, properties and applications of chalcogen-containing antioxidants

    Författare :Jonas Malmström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : In the first part, the preparation and properties of chalcogen-containing vitamin E analogues are described. The sulfur compound 3,3,4,6,7-pentamethyl-2,3-dihydrobenzo[b]thiophene-5-ol was prepared by two different routes using ionic and radical chemistry. Interesting rearrangements were observed in the two synthetic pathways. LÄS MER

  7. 5. Compounds with Non-Buttressed Metal-Metal Bond between Platinum and Thallium. Model Systems for Photoinduced Two-Electron-Transfer

    Författare :Mikhail Maliarik; KTH; []
    Nyckelord :thallium; platinum; cyanide; metal-metal bond; non-buttressed; heterometallic; photoinduced; electron transfer; redox reaction; NMR; chemical shift; spin-spin coupling constant; Raman; EXAFS; X-ray diffraction; equilibrium; oxidation state; oxidative;

    Sammanfattning : A new family of oligonuclear cyano compounds incorporatingtransition (Pt) and main group (Tl) metals bound with anon-buttressed Pt-Tl bond was synthesised in aqueous solution.The metal-metal linkage is formed in the reaction betweenplatinum and thallium in their stable oxidation forms, Pt(II)and Tl(III), orvice versa: Pt(IV) and Tl(I). LÄS MER