Sökning: "porphyrin"

Visar resultat 11 - 15 av 90 avhandlingar innehållade ordet porphyrin.

1. 11. Synthesis and Energy Transfer Studies of a Donor-Host-Acceptor Triad

   Författare :Jerker Mårtensson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; orientation factor; self-assembly; porphyrin; cations; F #246; rster; dimer; donor-host-acceptor triad; energy transfer; degenerate transition; diaza-crown ether;

   Sammanfattning : This dissertation describes the synthesis of a donor-host-acceptor triad, D-H-A, and its self-assembly into a well-ordered dimer. The energy transfer (EnT) properties of D-H-A as it is, in the presence of a variety of guest molecules and in the dimeric form are presented. LÄS MER

3. 12. Investigation of Kinetically Labile Supramolecu-lar System Addressing Substrate Selectivity in the Catalytic Epoxidations of Olefins

   Författare :Fabrice Odille; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Naturvetenskap; Natural science; enantioselectivity; Salen Mn III ; substrate selectivity; porphyrin; Jacobsen-Katsuki epoxidation; supramolecular catalysis; Hydrogen-bond; 2-pyridone;

   Sammanfattning : This thesis is devoted to the development and investigation of a supramolecular system used to catalyze Jacobsen-Katsuki epoxidations with the aim to attain substrate selectivity without product inhibition. The supramolecular catalyst is composed of two well-defined entities or units: a catalytic and a receptor. LÄS MER

4. 13. Studies of Biomimtic Oxidations and Racemizations

   Författare :Gábor Csjernyik; Jan-Erling Bäckvall; Serafino Gladiali; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxidation of alcohols; ruthenium; porphyrin; racemization;

   Sammanfattning : This thesis deals with studies of ruthenium-catalyzed hydrogen transfer reactions for oxidations and racemization.Through optimisation of the substrate-selective redox catalyst, the electron and proton transfer mediator (a benzoquinone derivative), and the oxygen-activating metal macrocycle a highly efficient biomimetic oxidation of secondary alcohols was obtained. LÄS MER

5. 14. The Fate of Electronically Excited States : Ultrafast Electron and Energy Transfer in Solvated Donor-Acceptor Systems

   Författare :Staffan Wallin; Leif Hammarström; Jan Davidsson; Eric Vauthey; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Electron transfer; Energy transfer; Anisotropy; Porphyrin; Ruthenium tris-bipyridine; Superexchange; Supramolecular; Donor-Acceptor; Charge transfer state; S2 state; Ultrafast; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : Processes where a molecule absorbs visible light and then disposes of the excess energy via electron/energy transfer reactions have an important role both in nature (e.g. in photosynthesis) and in many technical applications (e.g. LÄS MER

7. 15. Mimicking the Binary World: Photochromic Compounds in Molecular Logic

   Författare :Martin Hammarson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; DNA; dithienylethene; molecular logic; spiropyran; photochromism; porphyrin;

   Sammanfattning : The language of the binary world is used in, e.g., electronic circuits of a computer where a signal either can be on, known as 1 or off, known as 0. In the effort to make things smaller, molecules that mimic this binary world have been suggested as potential replacements for electronic circuits. LÄS MER