Search for dissertations about: "Lennart B.-Å. Johansson"

Showing result 1 - 5 of 8 swedish dissertations containing the words Lennart B.-Å. Johansson.

  2. 1. Extended Förster Theory of Electronic Energy Transport within Pairs of Reorienting Chromophoric Molecules

    Author : Nils Norlin; Lennart B.-Å. Johansson; Yehudi K. Levine; Umeå universitet; []
    Keywords : electronic energy migration transfer; extended Förster theory; orientation factor; DDEM; PDDEM; time-resolved fluorescence anisotropy; time-correlated single photon counting; Brownian dynamics; fysikalisk kemi; Physical Chemistry;

    Abstract : An extended Förster theory (EFT), previously derived (L. B.-Å. Johansson et al. READ MORE

  4. 2. Electronic Energy Transfer within Asymmetric Pairs of Fluorophores: Partial Donor-Donor Energy Migration (PDDEM)

    Author : Stanislav Kalinin; Lennart B.-Å. Johansson; Helge Lemmetyinen; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; fluorescence resonance energy transfer FRET ; donor-donor energy migration DDEM ; homotransfer; fluorescence relaxation; lifetimes; time-resolved fluorescence anisotropy; time-correlated single photon counting; distance measurements; protein structure; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi; Physical Chemistry; fysikalisk kemi;

    Abstract : A kinetic model of electronic energy migration within pairs of photophysically non-identical fluorophores has been developed. The model applies to fluorescent groups that exhibit different photophysical and spectral properties when attached to different positions in a macromolecule. READ MORE

  5. 3. Electronic Energy Migration/Transfer as a Tool to Explore Biomacromolecular Structures

    Author : Therese Mikaelsson; Lennart B.-Å. Johansson; Kristine Kilså; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fluorescence; electronic energy transfer; two-photon excitation; small ribosomal protein S16; macromolecular crowding; dextran 20; fysikalisk kemi; Physical Chemistry;

    Abstract : Fluorescence-based techniques are widely used in bioscience, offering a high sensitivity and versatility. In this work, fluorescence electronic energy migration/ transfer is applied to measure intramolecular distances in two types of systems and under various conditions. READ MORE

  6. 4. A new approach to the analyses of fluorescence depolarisation experiments in the presence of electronic energy transport

    Author : Oleg Opanasyuk; Lennart B-Å Johansson; Per-Olof Westlund; Yehudi Levine; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; electronic energy transfer; donor-donor energy migration; extended Förster theory; fluorescence depolarisation; two-photon excitation; computer simulations; genetic algorithms; fysikalisk kemi; Physical Chemistry;

    Abstract : A new and general procedure is described for a detailed analysis of time-resolved fluorescence depolarisation data in the presence of electronic energy migration. An isotropic ensemble of bifluorophoric molecules (D1-R-D2) has been studied to demonstrate its utility. READ MORE

  7. 5. Optical characterization of potential drugs and drug delivery systems

    Author : Erik Rosenbaum; Lennart B-Å Johansson; Sven Engström; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Pilicide; Ganglioside GM1 micelles; Drug Delivery; Elecronic Energy Transfer; UV-Vis Absorption; Fluorescence Spectroscopy; Biophysical chemistry; Biofysikalisk kemi; fysikalisk kemi; Physical Chemistry;

    Abstract : This Thesis is a characterization study on substances having potency as drugs as well as on a lipid based drug-delivery matrix. The optical properties of newly synthesized molecules with proven pilicide properties have been characterized with several spectroscopic methods. READ MORE