Sökning: "NATURVETENSKAP Fysik Atom- och molekylfysik Kemisk fysik"

Visar resultat 1 - 5 av 98 avhandlingar innehållade orden NATURVETENSKAP Fysik Atom- och molekylfysik Kemisk fysik.

1. 1. The effect of surface steps and oxides on the catalytic activity on model Pd and Rh catalysts

   Författare :Chu Zhang; Synkrotronljusfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Surface X-ray diffraction SXRD ; X-ray photonelectron spectroscopy; Catalytic activity; Oxide; Single Crystal surface; surface structure; vicinal surface; CO oxidation; stepped surface; Fysicumarkivet A:2018:Zhang;

   Sammanfattning : A catalyst is a substance that can speed up the rate of a chemical reaction without itself being consumed. Catalysts are crucial for chemical production industries, where about 90% of all chemicals are produced using catalysts. LÄS MER

3. 2. Reaction dynamics on highly excited states

   Författare :Johanna Brinne Roos; Åsa Larson; Ioan F. Schneider; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ab initio calculations; dissociative recombination; resonant ion-pair formation; mutual neutralization; molecular electronic states; molecule-electron collisions; quantum chemistry; molecular dynamics; Chemical physics; Kemisk fysik; Molecular physics; Molekylfysik; kemisk fysik; Chemical Physics;

   Sammanfattning : In this thesis I have performed theoretical studies on the reaction dynamics in few-atom molecules. In particular, I have looked at reaction processes in which highly excited resonant states are involved. LÄS MER

4. 3. XUV Laser Studies of Rydberg-Valence States in N2 and H+H- Heavy Rydberg States

   Författare :Maria Ofelia Vieitez Hornos; Lars-Erik Berg; G. C. Groenenboom; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spectroscopy; extreme utlraviolet; laser; diatomic molecules; laser-induced brakdown spectoscopy; Chemical physics; Kemisk fysik;

   Sammanfattning : .... LÄS MER

5. 4. Structural Transitions in Helical Peptides : The Influence of Water – Implications for Molecular Recognition and Protein Folding

   Författare :Martin Lignell; Hans-Christian Becker; Kaare Teilum; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; protein dynamics; protein folding; molten globule; time-resolved fluorescence spectroscopy; CD spectroscopy; molecular recognition; structure-function paradigm; Chemical physics; Kemisk fysik; Physical Chemistry; Fysikalisk kemi;

   Sammanfattning : Fluctuations in protein structure are vital to function. This contrasts the dominating structure-function paradigm, which connects the well-defined three-dimensional protein structure to its function. However, catalysis is observed in disordered enzymes, which lack a defined structure. LÄS MER

7. 5. 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