Sökning: "Transient absorption"

Visar resultat 1 - 5 av 94 avhandlingar innehållade orden Transient absorption.

1. 1. Studies of water vapor transport and sorption in wood

   Författare :Lars Wadsö; Avdelningen för Byggnadsmaterial; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; evaluation; measurements; non-Fickian behavior; absorption; sorption method; transient; unsteady-state; wood; sorption; surface mass transfer coefficient; water vapor; error analysis;

   Sammanfattning : This thesis deals with the evaluation of measurements of water vapor transport and sorption in wood. It mainly concerns measurements of the weight response of a sample after a step change in relative humidity. The thesis consists of an introduction and eight papers. The eight papers have the following contents: 1. LÄS MER

3. 2. Shining Light on Molecules : Electron Transfer Processes in Model Systems for Solar Energy Conversion Investigated by Transient Absorption Spectroscopy

   Författare :Jens Föhlinger; Leif Hammarström; Davidsson Jan; Benjamin Dietzek; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; photophysics; photoinduced electron transfer; transient absorption spectroscopy; laser spectroscopy; solar energy conversion; p-type DSSCs; Charge separation; recombination; mesoporous NiO;

   Sammanfattning : In the recent years, solar energy conversion has attracted a huge research interest due to the potential application for limiting the greenhouse effect. In many solar cells and solar fuel cells, understanding of charge transfer (CT) and recombination is important for future improvement of the overall efficiency. LÄS MER

4. 3. Ultrafast, Non-Equilibrium Electron Transfer Reactions of Molecular Complexes in Solution

   Författare :Jonas Petersson; Leif Hammarström; Antonín Vlček; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; electron transfer; laser; spectroscopy; transient absorption; anisortopy; inter ligand electron transfer; dye sensitized solar cell; DSSC; vibrational relaxation; ultrafast dynamics; fs spectroscopy; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

   Sammanfattning : Photoinduced electron transfer is a fundamentally interesting process; it occurs everywhere in the natural world. Studies on electron transfer shed light on questions about the interaction between molecules and how the dynamics of these can be utilized to steer the electron transfer processes to achieve a desired goal. LÄS MER

5. 4. Exploring Electron Transfer Dynamics of Novel Dye Sensitized Photocathodes : Towards Solar Cells and Solar Fuels

   Författare :Lei Zhang; Leif Hammarström; Yiying Wu; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electron transfer; Laser spectroscopy; Femtosecond spectroscopy; Transient absorption; NiO; DSSCs; DSSFDs; Charge separation; Solar energy conversion; Nanosecond photolysis; Photophysics; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

   Sammanfattning : The design of dyes for NiO-based dye-sensitized solar cells (DSSCs) has drawn attention owing to their potential applications in photocatalysis and because they are indispensable for the development of tandem dye-sensitized solar cells. The understanding of the electron transfer mechanisms and dynamics is beneficial to guide further dye design and further improve the performance of photocathode in solar cells and solar fuel devices. LÄS MER

7. 5. Singlet Fission - The Effects of Solvent Polarity and Conformation

   Författare :Rasmus Ringström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Singlet fission; rotational conformation; photoinduced electron transfer; transient absorption;

   Sammanfattning : Singlet fission (SF) is a process in which one initial high energy singlet excited state is converted into two triplet excited states of roughly half the energy of the initial state. This process has the potential to increase the efficiency of conventional solar cells by modifying the energy of the incident solar radiation to better match the energy input required to generate electricity. LÄS MER