Search for dissertations about: "inner-sphere"

Showing result 1 - 5 of 17 swedish dissertations containing the word inner-sphere.

2. 1. Mechanistic Studies on Ruthenium-Catalyzed Hydrogen Transfer Reactions

   Author : Jenny B. Åberg; Jan-Erling Bäckvall; Charles P. Casey; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; mechanistic studies; catalysis; ruthenium; hydrogen transfer; racemization; transfer hydrogenation; alcohols; ketones; amines; imines; inner-sphere; outer-sphere; solvent cage effect; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

   Abstract : Mechanistic studies on three different ruthenium-based catalysts have been performed. The catalysts have in common that they have been employed in hydrogen transfer reactions involving alcohols and ketones, amines and imines or both. READ MORE

4. 2. Theoretical studies of porphyrin proteins

   Author : Emma Sigfridsson; Beräkningskemi; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; molecular mechanics; quantum chemical calculations; electrostatic potential charges; atomic charges; ferrochelatase; cytochrome; myoglobin; Porphyrin; haem; QM MM; reorganisation energy; Theoretical chemistry; quantum chemistry; Teoretisk kemi; kvantkemi;

   Abstract : Different aspects of porphyrin proteins have been studied with theoretical methods. For example, we have studied: - The importance of hydrogen bonds for the discrimination between carbon monoxide and molecular oxygen by myoglobin, the oxygen carrier in muscles, modelling the active site both in vacuum and in the protein matrix - The inner-sphere reorganisation energy during electron transfer for cytochromes compared to other electron-transfer proteins, such as blue copper proteins and Fe-S clusters - The role of porphyrin distortions in the reaction mechanism of ferrochelatase, the enzyme that inserts an iron ion into protoporphyrin IX to make haem - The interaction between different metal sites in ferrochelatase In these studies we have used density functional theory, classical force field methods, and a combination of quantum chemistry and molecular mechanics. READ MORE

5. 3. Chemical Processes at the Water-Manganite (γ-MnOOH) Interface

   Author : Madeleine Ramstedt; Staffan Sjöberg; Per Persson; Lars Lövgren; Steven A. Banwart; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; manganite; γ-MnOOH; mineral surface; acid-base properties; adsorption; Cd II ; N- phosphonomethyl glycine; glyphosate; PMG; surface complex; dissolution; disproportionation; XPS; EXAFS; infrared spectroscopy; SEM; AFM; potentiometry; electrophoresis; Oorganisk kemi; Inorganic chemistry; Oorganisk kemi; oorganisk kemi; Inorganic Chemistry;

   Abstract : The chemistry of mineral surfaces is of great importance in many different areas including natural processes occurring in oceans, rivers, lakes and soils. Manganese (hydr)oxides are one important group to these natural processes, and the thermodynamically most stable trivalent manganese (hydr)oxide, manganit (γ-MnOOH), is studied in this thesis. READ MORE

6. 4. Characterization of aluminum in environmental systems using X-ray absorption and vibrational spectroscopy : The importance of organic matter

   Author : Kristoffer Hagvall; Torbjörn Karlsson; Per Persson; Lars Lövgren; Dan Berggren Kleja; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : The fate and behavior of many metals in the environment are highly dependent on interactions with natural organic matter (NOM), which is abundant in most soils and surface waters. The complexation with NOM can influence the speciation of the metals by affecting their hydrolysis and solubility. READ MORE

7. 5. Surface chemistry of Al and Si (hydr)oxides, with emphasis on nano-sized gibbsite (α-Al(OH)3)

   Author : Jörgen Rosenqvist; Umeå universitet; []
   Keywords : Gibbsite; silica; kaolinite; surface complexation; protonation; adsorption; carboxylates; modeling; AFM; IR; XPS;

   Abstract : This thesis contains an introduction to the surface chemistry of minerals in aqueous environment, and a summary of five manuscripts concerning adsorption reactions at the surfaces of nano-sized gibbsite (α-Al(OH)3), amorphous silica and kaolinite. Nano-sized gibbsite was synthesized and thoroughly characterized using X-ray diffraction, high-resolution transmission electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy. READ MORE