Sökning: "catalysis"

Visar resultat 21 - 25 av 673 avhandlingar innehållade ordet catalysis.

  1. 21. Versatile and Antique World of RNA : The Simplicity of RNA Mediated Catalysis

    Författare :Ema Kikovska; Leif Kirsebom; Venkat Gopalan; Uppsala universitet; []
    Nyckelord :Microbiology; RNA Catalysis; RNase P; Metal ions; tRNA Processing; Ribozyme; Mikrobiologi;

    Sammanfattning : RNA is the only biological molecule that can function both as a repository of information and as a catalyst. This, together with the ability to self-replicate, led to recognition of RNA as ‘prelude to life’.My work highlights some of the important features of RNA as a catalyst, exemplified by RNase P. LÄS MER

  3. 22. Photoredox catalysis harnessing oxygen-centered radicals

    Författare :Alica Ondrejkova; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxygen-centered radical; photoredox catalysis; C-H functionalization; visible light;

    Sammanfattning : Visible light provides an abundant and renewable source of energy with an ample capacity to mediate chemical transformations. Photoredox catalysis utilizes this energy for the generation of high-energy radical intermediates and strategically employs these reactive species in versatile chemical transformations. LÄS MER

  4. 23. Catalysis of Quantum Chain Photoisomerizations: Calculations of Triplet Energy Surfaces and Measurements of Quantum Yields

    Författare :Maria Brink; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; triplet state; density functional theory; potential energy surface; cis-trans isomerization; adiabatic isomerization; catalysis;

    Sammanfattning : Triplet state cis-trans photoisomerizations of olefins is the theme of this thesis, and the goal is to make the isomerizations as efficient as possible. The shape of the triplet potential energy surface (T1 PES) is essential for this, and the possibility of calculating these T1 PESs for two smaller olefins, using the computationally inexpensive density functional theory (DFT) methods, was investigated. LÄS MER

  5. 24. Development of Metal–Organic Frameworks for Catalysis : Designing Functional and Porous Crystals

    Författare :Fabian Carson; Xiaodong Zou; Jeffrey R. Long; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Metal–organic frameworks; heterogeneous catalysis; nanoparticles; metallolinkers; postsynthetic modification; postsynthetic exchange; Inorganic Chemistry; oorganisk kemi;

    Sammanfattning : Metal–organic frameworks, or MOFs, have emerged as a new class of porous materials made by linking metal and organic units. The easy preparation, structural and functional tunability, ultrahigh porosity, and enormous surface areas of MOFs have led to them becoming one of the fastest growing fields in chemistry. LÄS MER

  7. 25. Operando Gas Imaging in Heterogeneous Catalysis

    Författare :Jianfeng Zhou; Förbränningsfysik; []
    Nyckelord :planar laser-induced fluoresence; degenerate four wave mixing; gas phase; CO oxidation; model catalyst; hetergeneous catalysis; laser-diagnostiska tekniker; gasfasdetektering; modellkatalys; heterogen katalys;

    Sammanfattning : This thesis deals with the development and application of laser-based techniques, for gas phasecharacterization/gas imaging in heterogeneous catalysis. Two techniques are presented: planar laser-induced fluorescence (PLIF) and degenerate four wave mixing (DFWM). LÄS MER