Sökning: "Electron paramagnetic resonance EPR"

Visar resultat 11 - 15 av 33 avhandlingar innehållade orden Electron paramagnetic resonance EPR.

1. 11. Probing Paramagnetic Systems by Solid-State NMR Spectroscopy

   Författare :José P. Carvalho; Andrew J. Pell; Sharon Ashbrook; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Solid-state NMR; Magic-Angle Spinning; Paramagnetic NMR; Frequency-Swept Adiabatic Pulses; Quantum Chemistry; Quadrupolar Interaction; Physical Chemistry; fysikalisk kemi;

   Sammanfattning : Paramagnetic systems have a wide range of applications ranging from energy storage or conversion to catalytic processes, metalloproteins and light-emitting materials. Over the recent years nuclear magnetic resonance (NMR) spectroscopy has become an established tool for studying the structural and electronic properties of these systems, largely because it can provide a link between the structure and the bulk properties. LÄS MER

3. 12. Formulation and characterization of W/O nano-dispersions for bioactive delivery applications

   Författare :Maria D. Chatzidaki; Aris Xenakis; Bert van Bavel; Werner Kunz; Örebro universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nano-dispersions; encapsulation; food; DLS; EPR; Cryo-TEM; SAXS; pH-stat; digestion; antioxidants; gastric lipase; pancreatic lipase; Kemi; Chemistry;

   Sammanfattning : The main objective of this study was the formulation of food-grade water-in-oil (W/O) nano-dispersions based mainly on medium or long-chain triglycerides. Two types of dispersions were formulated and structurally compared, namely emulsions and microemulsions. LÄS MER

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

   Författare :Paulina Geijer; Biokemi och Strukturbiologi; []
   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

5. 14. Iron-nitrogen containing carbon catalysts for oxygen reduction in fuel cells

   Författare :Caroline Janson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; active site; mesoporous carbon; fuel cell; electron paramagnetic resonance; oxygen reduction reaction; cathode catalyst; non-precious metal catalyst;

   Sammanfattning : New solutions to efficiently convert energy are needed to mitigate global climate changes and sustain the needs of the growing population. An energy device with high potential is the proton exchange membrane (PEM) fuel cell. PEM fuel cells can convert chemical energy to electrical energy with extraordinary high conversion efficiency. LÄS MER

7. 15. Making Radical Cations Live Longer

   Författare :Ola Persson; Kemisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spin trapping.; 3-hexafluoropropan-2-ol; 3; 1; thallium III -based oxidants; Radical cations; electron paramagnetic resonance; Physics; Fysik; Chemistry; Kemi;

   Sammanfattning : The acid-catalyzed rearrangement of 1,4,5,8-tetramethylnaphthalene was used to determine the acidity of media used for EPR spectral studies of radical cations. The radical cations of methyl-substituted naphthalenes were shown to undergo dimerization reactions. LÄS MER