Sökning: "Molecular beam"

Visar resultat 16 - 20 av 228 avhandlingar innehållade orden Molecular beam.

  1. 16. Molecular-Level Investigations of Water-Organic Systems of Atmospheric Relevance

    Författare :Sofia M. Johansson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; EMB method; desorption kinetics; water uptake; organic surfaces;

    Sammanfattning : It is known that aerosol particles may have warming and/or cooling effects on the climate and negative health effects that depend on their chemical and physical properties. However, current understanding of atmospheric particles’ effects is poor due to the diversity of their constituents and associated variations in properties. LÄS MER

  3. 17. Synthesis of complex organics via molecular growth mechanisms : Combined experimental and theoretical studies on ion-neutral reactions of C2H2N+ with ubiquitous hydrocarbons in Titan's ionosphere

    Författare :Pantea Fathi; Wolf Geppert; Paul Scheier; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Astrochemistry; Complex molecules; Ion-neutral reactions; Mass spectrometry; Planetary and satellite atmospheres; Titan; kemisk fysik; Chemical Physics;

    Sammanfattning : To provide insights on the molecular growth mechanisms leading to large carbon and nitrogen-bearing species in Titan’s ionosphere, laboratory measurements of ion-neutral reactions were conducted and the results are presented in the following doctoral dissertation. The product ions of the C2H2N+ reactions with saturated and unsaturated neutral hydrocarbons have been investigated using Guided Ion Beam Mass Spectrometer (GIB-MS). LÄS MER

  4. 18. Spectroscopy of Stable and Radioactive Negative Ions

    Författare :Annie Ringvall-Moberg; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atomic Physics; ISOLDE; CERN; Electron Correlation; Electron Affinity; Photodetachment; Negative Ions; Anions; Radioisotopes; Laser Photodetachment Spectroscopy; Resonance Ionization; Neutral Particle Detection; Wigner Threshold Law; Molecular Dissociation; RFQcb; DESIREE; Radiative Lifetimes;

    Sammanfattning : Negative ions are unique quantum systems which are of fundamental interest within the field of atomic physics due to the importance of the electron correlation in their creation, stability, and existence. Properties of these ions, such as the electron affinity, i.e. LÄS MER

  5. 19. Multi-Level Lossless Phase Modulation in Liquid Crystals for High-Speed Spatial Light Modulators

    Författare :David Engström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; phase measurements; polarization; phase modulation; beam steering; Spatial light modulators; diffractive optics; ferroelectric liquid crystals;

    Sammanfattning : The spatial light modulator (SLM) is a compact device that enables highly precise control of light propagation with low drive voltages and no moving parts. By imposing a certain phase modulation onto the incident lightwave, functions such as multi-beam steering, beam shaping, and air turbulence corrections can be achieved in realtime. LÄS MER

  7. 20. Stark Spectroscopy, Lifetimes and Coherence Effects in Diatomic Molecular Systems

    Författare :Annie Hansson; Peder Royen; Michel Herman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; diatomic; dipole moment; Stark effect; lifetimes; transition moment; coherence effects; EIT; Autler-Townes; Chemical physics; Kemisk fysik;

    Sammanfattning : In this dissertation is exemplified how different laser based methods are applied in high-resolution spectroscopic studies of internal properties of diatomic molecules.A molecular beam apparatus assembly is described, where a laser ablation source is combined with a time-of-flight mass spectrometer. LÄS MER