Sökning: "bacteriochlorophyll a"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden bacteriochlorophyll a.

  1. 1. Ultrafast Dynamics in Ground and Excited States of Porphyrin Molecules

    Författare :Peter Martinsson; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; intra- and intermolecular dynamics.; Zn-porphyrin; bacteriochlorophyll a; chlorophyll b; Femtosecond transient absorption spectroscopy; chlorophyll a; Physical chemistry; Fysikalisk kemi;

    Sammanfattning : This thesis describes inter and intramolecular dynamics in porphyrin molecules. To create a basis for understanding the energy and electron transfer processes in photosynthesis, the ultrafast dynamics of monomeric chlorophyll a, chlorophyll b and bacteriochlorophyll a were studied with ultrashort laser pulses. LÄS MER

  3. 2. The photophysics and functions of some naturally occurring carotenoids

    Författare :Helena Billsten; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Fysikalisk kemi; xanthophyll-binding proteins; vibrational relaxation; light-harvesting complexes; carotenoid aggregates; carotenoids; excited states; femtosecond pump-probe spectroscopy; xanthophylls;

    Sammanfattning : Carotenoids are one of the most widespread and important group of pigments in Nature and they can act as light-harvesting agents, photoprotectors and antioxidants. Mechanisms of their multiple functions are not fully understood mainly because their complicated photophysics involving ?dark? excited states. LÄS MER

  4. 3. Quantum Coherence for Light Harvesting

    Författare :David Palecek; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Coherent two-dimensional spectroscopy; Quantum coherence; Light harvesting; Photosynthetic reaction center; Energy transfer;

    Sammanfattning : Almost all life on Earth depends on the products of photosynthesis — the biochemical process whereby solar energy is stored as chemical-rich compounds. The energy of captured photons is transferred through a network of pigment-protein complexes towards the reaction center. LÄS MER

  5. 4. Formation and Dynamics of Molecular Excitons and their Fingerprints in Nonlinear Optical Spectroscopy

    Författare :Pär Kjellberg; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supraledare; magnetisk resonans; spektroskopi; Physical chemistry; Fysikalisk kemi; Photochemistry; Fotokemi; Kondenserade materiens egenskaper:elektronstruktur; magnetiska och optiska ; egenskaper elektriska; supraconductors; magnetic resonance; relaxation; spectroscopy; Fysik; Chemistry; Kemi; Condensed matter:electronic structure; electrical; Physics; Redfield relaxation theory ; Inhomogeneous broadening ; Time-dependent density functional theory ; Conjugated polymers ; Three-pulse photon echo ; Molecular excitons ; magnetic and optical properties; Nonlinear spectroscopy ;

    Sammanfattning : An efficient transfer of energy in molecular systems has proven to be of fundamental importance both in nature and industrial applications. The ability of molecules to work together forming collective excitations, so-called excitons, plays a key role in for example the extraordinary fast energy transfer involved in the first steps of photosynthesis. LÄS MER

  7. 5. Insights into structure and dynamics of the AAA+ motor of magnesium chelatase

    Författare :Joakim Lundqvist; Biokemi och Strukturbiologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bioinformatik; biomathematics biometrics; Bioinformatics; medical informatics; Rhodobacter capsulatus; Tetrapyrrole; Mutants; Magnesium chelatase; Cryo-Electron microscopy single-particle 3D reconstruction; Chlorophyll biosynthesis; AAA proteins; ATPase; medicinsk informatik; biomatematik; Molecular biophysics; Molekylär biofysik; Natural science; Naturvetenskap;

    Sammanfattning : The insertion of Mg2+ into protoporphyrin IX represents the first committed step in the chlorophyll and bacteriochlorophyll biosynthetic pathways. The reaction is catalyzed by the multisubunit enzyme Mg-chelatase, which consists of three subunits, known as I (molecular weight ~40 kDa), D (~70 kDa), and H (~140 kDa). LÄS MER