Sökning: "metallicity"

Visar resultat 16 - 20 av 25 avhandlingar innehållade ordet metallicity.

1. 16. Ca-Pd/Pt-Ge Compounds on the Zintl Border

   Författare :Isa Doverbratt; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Zintl compounds form a category in intermetallic chemistry somewhere between metallic and ionic compounds. Classical Zintl compounds form between electropositive and electronegative elements, such as the alkaline earth metals and the p-block elements, i.e. elements with a relatively large electronegativity difference. LÄS MER

3. 17. Galactic archaeology with metal-poor stars

   Författare :Thomas Nordlander; Andreas J. Korn; Karin Lind; Ulrike Heiter; David L. Lambert; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stars: abundances; radiative transfer; stars: Population II; stars: Population III;

   Sammanfattning : The chemical fingerprints of old, metal-poor stars can be used to unravel the events of the newborn Universe and help us understand the properties of the first stars and star clusters. The study of nearby stars to infer properties in the distant past is often referred to as Galactic archaeology. LÄS MER

4. 18. Observational Studies of the Chemical Evolution in the Galactic Thin and Thick Disks

   Författare :Thomas Bensby; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomi; Fysicumarkivet A:2004:Bensby;

   Sammanfattning : The origin and evolution of the thin and thick disks in the Galaxy have been studied by means of detailed stellar abundances. High-resolution spectra of 102 F and G dwarf stars have been obtained with the spectrographs on the ESO 3.6-m and ESO 1. LÄS MER

5. 19. Core-collapse Supernovae : Theory vs. Observations

   Författare :Dennis Alp; Josefin Larsson; Sergey Tsygankov; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astrophysics; Supernovae; Fysik; Physics;

   Sammanfattning : A core-collapse supernova (CCSN) is an astronomical explosion that indicates the death of a massive star. The iron core of the star collapses into either a neutron star or a black hole while the rest of the material is expelled at high velocities. LÄS MER

7. 20. Towards a Chemisorption Model for Transition-Metal Nitrides and Carbides from Density-Functional Theory: A TiN and TiC Case Study

   Författare :Aleksandra Vojvodic; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Titanium; Titanium nitride; Transition-metal nitrides and carbides;

   Sammanfattning : Since the 1960's, a number of models for chemisorption on metals has beenpresented, most notably the Anderson-Grimley-Newns model for metals and thed-band model of Hammer and Nørskov for transition metals. The intention of this thesis is to explore the adsorption on transition-metal nitrides andcarbides, technologically interesting materials (in, e. LÄS MER