Sökning: "Magneto"

Visar resultat 16 - 20 av 121 avhandlingar innehållade ordet Magneto.

1. 16. Origin of solar surface activity and sunspots

   Författare :Sarah Jabbari; Axel Brandenburg; Laurene Jouve; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magneto-hydrodynamics; solar physics; dynamo theory; Astronomy; astronomi;

   Sammanfattning : Sunspots and active regions are two of the many manifestations of the solar magnetic field. This field plays an important role in causing phenomena such as coronal mass ejections, flares, and coronal heating. Therefore, it is important to study the origin of sunspots and active regions and determine the underlying mechanism which creates them. LÄS MER

3. 17. From mean-field hydromagnetics to solar magnetic flux concentrations

   Författare :Koen Kemel; Axel Brandenburg; Alexander Ruzmaikin; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magneto-hydrodynamics; solar physics; turbulence; Astronomy; astronomi;

   Sammanfattning : The main idea behind the work presented in this thesis is to investigate if it is possible to find a mechanism that leads to surface magnetic field concentrations and could operate under solar conditions without postulating the presence of magnetic flux tubes rising from the bottom of the convection zone, a commonly used yet physically problematic approach.In this context we study the ‘negative effective magnetic pressure effect’: it was pointed out in earlier work (Kleeorin et al. LÄS MER

4. 18. The Influence of Interlayer Exchange Coupling on Magnetic Ordering in Fe-based Heterostructures

   Författare :Martin Pärnaste; Björgvin Hjörvarsson; Bryan Hickey; Uppsala universitet; []
   Nyckelord :Physics; magnetism; magnetic dimensionality; MOKE; magneto-optics; hydrogen loading; phase transitions; Fysik;

   Sammanfattning : Temperature dependent magnetization measurements were conducted on Fe-based heterostructures. A linear increase of the magnetic critical temperature with increasing Fe thickness was found for Fe/V superlattices with strong interlayer exchange coupling. LÄS MER

5. 19. On mapping epilepsy : magneto- and electroencephalographic characterizations of epileptic activities

   Författare :Karin Westin; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :;

   Sammanfattning : Epilepsy is one of the most common neurological disorder, affecting up to 10 individuals per 1000 persons. The disorder have been known for several thousand years, with the first clinical descriptions dating back to ancient times. Nonetheless, characterization of the dynamics underlying epilepsy remains largely unknown. LÄS MER

7. 20. On ferromagnetic thin films and two-dimensional magneto-optic photonic crystals

   Författare :Amir A. Jalali Roudsar; Ari Friberg; Ilkka Tittonen; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; photonic crystals; physics; Fysik; Physics; Fysik;

   Sammanfattning : This thesis presents results in two different neighboring areas of research: the magnetic properties of thin ferrite films and the application of the films in two-dimensional photonic crystals.In the first part, we investigate the accuracy of the customary method for determining the magnetic anisotropy constants of ferrite films by ferromagnetic resonance (FMR) experiment. LÄS MER