Sökning: "acidic protons"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden acidic protons.

  1. 1. Alkylation and Hydrodearomatization over Zeolite cCatalysts

    Författare :Jun-Jun Yuan; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Acid catalysts; ZSM-5 catalysts; ethylbenzene; toluene; temperature; diesel fuel; hydrodearomatization; benzene; acidic protons; activity and selectivity; aqueous ethanol; Pt Y zeolite; gasoline; pressure; GC; diethylbenzene; Hydrocracking; SiO2 Al2O3 ratio; alkylation of aromatics; Brønsted acids;

    Sammanfattning : The alkylation of aromatic compounds is widely used in the large-scale synthesis of petrochemicals, and a great variety of fine chemicals and intermediates. Acid catalysts used for alkylation of aromatic hydrocarbons are Brønsted acids containing acidic protons. LÄS MER

  2. 2. Effects of Protons and Small Alcohols on the Oxygen-Evolving Complex of Photosystem II

    Detta är en avhandling från Biochemistry, Center for Chemistry and Chemical Engineering, Lund University

    Författare :Paulina Geijer; [2000]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; EPR; pH; methanol; S3; S2; S0; YZ; Mn cluster; Oxygen-evolving complex; S-states; Biochemistry; Metabolism; Biokemi; metabolism;

    Sammanfattning : Higher plants and algae use oxygenic photosynthesis to convert solar energy to reducing equivalents and chemical energy. The ultimate electron donor to oxygenic photosynthesis is water. Oxidation of water to oxygen occurs in the oxygen-evolving complex (OEC) in Photosystem II (PSII). The OEC is composed of four Mn atoms, Ca2+ and Cl-. LÄS MER

  3. 3. Structural elements involved in protein-mediated proton transfer Implications from studies of cytochrome c oxidase

    Detta är en avhandling från Stockholm : Department of Biochemistry and Biophysics, Stockholm University

    Författare :Ann-Louise Johansson; Stockholms universitet.; [2013]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cytochrome c oxidase; proton transfer; biokemi; Biochemistry;

    Sammanfattning : Proton transfer is one of the most common reactions in biological systems. During energy conversion inside a cell, proton transfer is crucial to maintain an electrochemical proton gradient across the cell membrane. This gradient is in turn used to e.g. LÄS MER

  4. 4. Physiological regulation of the high-affinity phosphate uptake system in the yeast Saccharomyces cerevisiae

    Detta är en avhandling från Stockholm : Institutionen för biokemi och biofysik

    Författare :Johanna Pattison-Granberg; Stockholms universitet.; [2006]

    Sammanfattning : Yeast cells can be found in a wide variety of environments, demonstrating that these cells are capable of adapting to changes in the external milieu. Inorganic phosphate (Pi) is an essential nutrient for all organisms and Saccharomyces cerevisiae cells take up phosphate from the external environment via two different systems, i.e. LÄS MER

  5. 5. Impact of Secondary Interactions in Asymmetric Catalysis

    Detta är en avhandling från Stockholm : KTH

    Författare :Anders Frölander; KTH.; [2007]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; secondary interaction; hydrogen bond; chiral ligand; allylic alkylation; hydrosilylation; cyanation; pymox; box; PHOX; pybox; palladium; iridium; rhodium; Lewis acid; Lewis base; NATURAL SCIENCES Chemistry Organic chemistry; NATURVETENSKAP Kemi Organisk kemi;

    Sammanfattning : This thesis deals with secondary interactions in asymmetric catalysis and their impact on the outcome of catalytic reactions.The first part revolves around the metal-catalyzed asymmetric allylic alkylation reaction and how interactions within the catalyst affect the stereochemistry. LÄS MER