Search for dissertations about: "fourier transform infrared spectroscopy"

Showing result 6 - 10 of 100 swedish dissertations containing the words fourier transform infrared spectroscopy.

  1. 6. Vibrational Spectroscopy of Surface Adsorbates on Metal Surfaces. Experiments and Calculations

    Author : Ragnar K Ásmundsson; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; ab initio electronic structure calculations; Fermi resonance; vibrational spectroscopy; Reflection absorption infrared spectroscopy; Fourier transform infrared spectroscopy; Cu 100 and W 110 single crystal surfaces; Physics; Fysik;

    Abstract : This work deals with a detailed analysis of the vibrational spectra of methoxy (CH3O-) and ethoxy (CH3CH2O-) on W(110) and Cu(100) single crystal surfaces. By using theoretical ab initio quantum mechanical modeling, it is demonstrated that an unprecedented quantitative understanding of the vibrational frequencies of a surface adsorbate can be obtained. READ MORE

  2. 7. Infrared spectroscopy as a tool to reconstruct past lake-ecosystem changes : Method development and application in lake-sediment studies

    Author : Carsten Meyer-Jacob; Richard Bindler; Hendrik Vogel; Jan Karlsson; John F. Boyle; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fourier transform infrared spectroscopy; visible-near infrared spectroscopy; PLS regression; biogenic silica; climate change; carbon cycling; lake-water quality; geochemistry; paleolimnology; Holocene; Lake El’gygytgyn; Torneträsk;

    Abstract : Natural archives such as lake sediments allow us to assess contemporary ecosystem responses to climate and environmental changes in a long-term context beyond the few decades to at most few centuries covered by monitoring or historical data. To achieve a comprehensive view of the changes preserved in sediment records, multi-proxy studies – ideally in high resolution – are necessary. READ MORE

  3. 8. Infrared and Photoelectron Spectroscopic Studies of Adsorbates on Solid Surfaces: Experiments and DFT Calculations

    Author : Jakob Blomquist; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; magnetic resonance; supraconductors; magnetic and optical properties; electrical; Solid Surfaces; Chemistry; Kemi; Condensed matter:electronic structure; FTIR spectroscopy; DFT Cluster calculations; Anharmonicity; Photoelectron spectroscopy; relaxation; spectroscopy; Kondenserade materiens egenskaper:elektronstruktur; egenskaper elektriska; magnetiska och optiska ; supraledare; magnetisk resonans; spektroskopi; Surface and boundary layery chemistry; Ytkemi; gränsskikt;

    Abstract : In general, the more complex and real a system is, with all its interactions with solvents and contaminations etc., the harder it is to accurately model it and reproduce the experimental results by calculations. READ MORE

  4. 9. Continuous-filtering Vernier spectroscopy

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

    Abstract : 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. READ MORE

  5. 10. Measurements of High-Precision Atomic Data with Applications to Astrophysics and Cosmology

    Author : Maria Aldenius; Astronomi - Genomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; atomic data; Ca; Cr; Fe; Mn; Mg; metal-poor stars; fine-structure constant; Fourier transform spectroscopy; nebulae; oscillator strengths; spectroscopy; wavelengths; Ti; Zn; Astronomy; Astronomi; Atomic and molecular physics; Atom- och molekylärfysik; rymdvetenskap; space research; cosmic chemistry; kosmisk kemi; branching fractions;

    Abstract : Investigations of astrophysical spectra require accurate atomic data, such as wavelengths and transition probabilities. This thesis provides high-precision atomic data for astrophysical and cosmological applications. The measurements have been carried out using Fourier transform spectrometry on light produced in a hollow cathode light source. READ MORE