Sökning: "optik"

Visar resultat 16 - 20 av 920 avhandlingar innehållade ordet optik.

1. 16. Whiteness and Fluorescence in Paper : Perception and Optical Modelling

   Författare :Ludovic Gustafsson Coppel; Per Edström; Håkan Olin; Caisa Johansson; Markku Hauta-Kasari; Mittuniversitetet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Paper Whiteness; Fluorescence Whitening Agents; Kubelka-Munk; light scattering; paper industry applications; Colour Appearance Models; CIECAM02; Monte Carlo; Optics; Optik;

   Sammanfattning : This thesis is about modelling and predicting the perceived whiteness of plain paper from the paper composition, including fluorescent whitening agents. This includes psycho-physical modelling of perceived whiteness from measurable light reflectance properties, and physical modelling of light scattering and fluorescence from the paper composition. LÄS MER

3. 17. Energy Transfer Patterns in Photosynthetic Antenna System of Purple Bacteria

   Författare :Susan Hess; Kemisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; optics; Electromagnetism; mykologi; virologi; bakteriologi; photosynthesis; Mikrobiologi; Picosecond and femtosecond spectroscopy; energy transfer; purple bacteria.; Microbiology; bacteriology; mycology; virology; acoustics; Elektromagnetism; optik; akustik; Fysicumarkivet A:1997:Hess;

   Sammanfattning : Steady state and time-resolved absorption and fluorescence spectroscopy have been used to investigated the energy transfer in photosynthetic purple bacteria. Picosecond light pulses were used in measurements of Rb. LÄS MER

4. 18. Attosecond Optical and Electronic Wave Packets

   Författare :Per Johnsson; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; optik; acoustics; optics; Electromagnetism; Ionization Dynamics; Electron Wave Packet Interferometry; Electron Wave Packet Control; Pulse Characterization; High-Order Harmonics; Attosecond Pulse Trains; Atom- och molekylärfysik; Atomic and molecular physics; akustik; Elektromagnetism;

   Sammanfattning : When a low-frequency laser pulse is focused to a high intensity in a gas, the electric field of the laser may become comparable to, or even exceed, the electric field between the electrons and the nucleus in the atom. Under such conditions, through a process known as high-order harmonic generation, bursts of extreme ultraviolet radiation may be emitted, with durations in the attosecond domain (1 as = 10^{-18} s), which is the time-scale of electronic processes. LÄS MER

5. 19. Extended Jaynes-Cummings Models In Cavity Qed

   Författare :Jonas Larson; Stig Stenholm; Peter L. Knight; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Optics; Optics; Optik;

   Sammanfattning : Due to the improvement within cavity quantum electrodynamics experiments during the last decades, what was former seen as 'toy models' are today realized in laboratories. A controlled isolated coherent evolution of one or a few atoms coupled to a single mode inside a cavity is achievable. LÄS MER

7. 20. Development of diode laser-based absorption and dispersion spectroscopic techniques for sensitive and selective detection of gaseous species and temperature

   Författare :Lemthong Lathdavong; Ove Axner; Jürgen Röpcke; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Absorption Spectrometry AS ; Wavelengh Modulation Absorption Spectrometry WMAS ; Faraday Modulation Spectrometry FAMOS ; Tunable Diode Laser Absorption Spectrometry TDLAS ; Optics; Optik; fysik; Physics;

   Sammanfattning : The main aim of this thesis has been to contribute to the ongoing work with development of new diode-laser-based spectroscopic techniques and metho­do­lo­gies for sensitive detection of molecules in gas phase. The techniques under scrutiny are tunable diode laser absorption spectrometry (TDLAS) and Faraday modulation spectrometry (FAMOS). LÄS MER