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Visar resultat 1 - 5 av 109 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Development of laser spectroscopy for scattering media applications

   Författare :Mats Andersson; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Laserteknik; Laser technology; Atom- och molekylärfysik; Atomic and molecular physics; Fysik; Physics; coherent sampling; optical sensor; light absorption; noninvasive measurement; diode laser; scattering of light; laser spectroscopy; fluorescence spectroscopy; remote sensing; Lidar; DIAL;

   Sammanfattning : Laser spectroscopy for both large and small spatial scales has been developed and used in various applications ranging from remote monitoring of atmospheric mercury in Spain to investigation of oxygen contents in wood, human sinuses, fruit, and pharmaceutical solids. Historically, the lidar group in Lund has performed many differential absorption lidar (DIAL) measurements with a mobile lidar system that was first described in 1987. LÄS MER

3. 2. Laser-based absorption spectrometry : development of NICE-OHMS towards ultra-sensitive trace species detection

   Författare :Florian Schmidt; Ove Axner; Livio Gianfrani; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; absorption spectrometry; trace species detection; fiber laser; modulation; cavity-enhanced spectroscopy; optical saturation; laser frequency stabilization; free-spectral-range; Physics; Fysik;

   Sammanfattning : Laser-based absorption spectroscopy (AS) is a powerful technique for qualitative and quantitative studies of atoms and molecules. An important field of use of AS is the detection of species in trace concentrations, which has applications not only in physics and chemistry but also in biology and medicine, encompassing environmental monitoring, regulation of industrial processes and breath analysis. LÄS MER

4. 3. Diode laser spectroscopy in extended wavelength ranges

   Författare :Ulf Gustafsson; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; diode-laser spectroscopy; frequency-modulation spectroscopy; frequency conversion; fluorescence spectroscopy; scattering; diffraction; Fysicumarkivet A:2000:Gustafsson; Atomic and molecular physics; Atom- och molekylärfysik; absorption spectroscopy;

   Sammanfattning : Diode laser spectroscopy performed in the ultraviolet, visible and infrared spectral regions is presented. The accessible wavelength range for visible and near-infrared diode lasers is extended by the use of sum- and difference-frequency generation. LÄS MER

5. 4. Laser Absorption Spectroscopy of Gas in Scattering Media

   Författare :Märta Lewander; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; medical diagnosis; gas analysis; absorption spectroscopy; diode laser spectroscopy; light scattering; food-package monitoring; GASMAS;

   Sammanfattning : Absorption spectroscopy constitutes a chemical analysis tool which can be applied to various samples and application fields. This thesis focuses on gas absorption spectroscopy with the means of diode lasers - tunable diode laser absorption spectroscopy, TDLAS. LÄS MER

7. 5. Continuous-filtering Vernier spectroscopy

   Författare :Chuang Lu; Aleksandra Foltynowicz; Ove Axner; Wei Ren; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spectroscopy; spectrometer; laser; optical frequency comb; optical cavity; NIR; MIR; flame; robust; time resolution; spectrum; fysik; Physics;

   Sammanfattning : Continuous-filtering Vernier spectroscopy (CF-VS) is a laser-based detection technique that combines the broad spectral coverage of an optical frequency comb (OFC) with the enhanced interaction length provided by an optical cavity. The resonances of the cavity filter the OFC to a small group of comb modes that probe the transitions of the species present in the cavity. LÄS MER