Sökning: "solvation effects"

Visar resultat 21 - 25 av 33 avhandlingar innehållade orden solvation effects.

  1. 21. Quantum Chemical Cluster Modeling of Enzymatic Reactions

    Författare :Rongzhen Liao; Fahmi Himo; Robert Deeth; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cluster approach; density functional theory; B3LYP; enzyme; mechanism; dinuclear; trinuclear; zinc; tungsten; hydrolysis; decarboxylation; formaldehyde oxidation; hydration; methyl transfer; Quantum chemistry; Kvantkemi; organisk kemi; Organic Chemistry;

    Sammanfattning : The Quantum chemical cluster approach has been shown to be quite powerful and efficient in the modeling of enzyme active sites and reaction mechanisms. In this thesis, the reaction mechanisms of several enzymes have been investigated using the hybrid density functional B3LYP. LÄS MER

  3. 22. Molecular Recognition Mechanisms: Thermodynamics and Polarization Spectroscopy of DNA--Intercalator Complexes

    Författare :Hans-Christian Becker; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; groove-binding; DNA; intercalation; linear dichroism; polarization spectroscopy; thermodynamics; enthalpy--entropy compensation;

    Sammanfattning : Mechanisms for molecular recognition in DNA--intercalator complexes have been investigated by optical spectroscopy. The effect of electrical charge on binding geometry and binding thermodynamics was studied using 2,7-diazapyrene (DAP) and its N-methylated cations DAP+ and DAP2+ as model ligands. LÄS MER

  4. 23. Aqueous Solutions as seen through an Electron Spectrometer : Surface Structure, Hydration Motifs and Ultrafast Charge Delocalization Dynamics

    Författare :Niklas Ottosson; Svante Svensson; Olle Björneholm; Gunnar Öhrwall; Clemens Heske; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Water; Aqueous solutions; Ions; Molecular Hydration; Electron dynamics; Atmospheric Chemistry; Hydrolysis; Acid-Base Chemistry; Interatomic Coulombic Decay; ICD; Liquid Micro-Jet; X-ray Photoelectron Spectroscopy; XPS; Auger Electron Spectroscopy; AES; MAX-lab; BESSY; Physics; Fysik; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In spite of their high abundance and importance, aqueous systems are enigmatic on the microscopic scale. In order to obtain information about their geometrical and electronic structure, simple aqueous solutions have been studied experimentally by photo- and Auger electron spectroscopy using the novel liquid micro-jet technique in conjunction with synchrotron radiation. LÄS MER

  5. 24. Theoretical Studies on Water Oxidation Catalysts - from Solvent to Interfaces

    Författare :Shaoqi Zhan; Mårten Ahlquist; Núria López; KTH; []
    Nyckelord :Teoretisk kemi och biologi; Theoretical Chemistry and Biology;

    Sammanfattning : Water splitting contains two half-reactions, the water oxidation reaction and the hydrogen reduction reaction. In water oxidation, protons and electrons will be generated to offer two elemental components for production of fuels, such as H2 and CH3OH. LÄS MER

  7. 25. Exploring the Molecular Behavior of Carbohydrates by NMR Spectroscopy : Shapes, motions and interactions

    Författare :Olof Engström; Göran Widmalm; Anthony S. Serianni; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NMR spectroscopy; NMR relaxation; DNMR; CORCEMA-ST; carbohydrates; caffeine; O-antigen; glycofullerenes; organisk kemi; Organic Chemistry;

    Sammanfattning : Carbohydrates are essential biomolecules that decorate cell membranes and proteins in organisms. They are important both as structural elements and as identification markers. Many biological and pathogenic processes rely on the identification of carbohydrates by proteins, thereby making them attractive as molecular blueprints for drugs. LÄS MER