Search for dissertations about: "electron cooling"

Showing result 16 - 20 of 101 swedish dissertations containing the words electron cooling.

  2. 16. Precise measurements of electron affinities using Laser Photodetachment Threshold Spectroscopy

    Author : Jose Eduardo Navarro Navarrete; Henning Zettergren; Henning T. Schmidt; Jan-Erik Rubensson; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; fysik;

    Abstract :  In this work we have performed Laser Photodetachment Threshold Spectroscopy (LPTS) to determine the electron affinities of the atomic species $^{133}$Cs and $^{16}$O with high precision. The negative ion of Cesium has been produced and investigated at the Gothenburg University Negative Ion and Laser LAboratory (GUNILLA) while the Oxygen anion have been studied in the Double ElectroStatic Ion Ring ExpEriment (DESIREE) at Stockholm University. READ MORE

  4. 17. Runaway electrons and Alfvén eigenmodes in tokamaks

    Author : Håkan Smith; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; two-way diffusion equation; compressional Alfvén eigenmode; fusion plasma physics; tokamak disruption; runaway electron; Alfvén cascade;

    Abstract : Runaway electrons can be generated as a consequence of the rapid thermal quench of the plasma in a tokamak disruption. If the time scale of this cooling is short compared to the collision time in the tail of the electron velocity distribution, incomplete thermalisation of this tail leads to a burst of runaway production. READ MORE

  5. 18. Some aspects of convection as well as graphite and carbide formations during casting

    Author : Fareed Ashraf Khan; Michael Vynnycky; Pär Jönsson; Bo Rogberg; Hasse Fredriksson; Jessica Elfsberg; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carbides; heat treatment; cast iron; ball bearing steel; casting; cooling rate; structure analysis; nodule distribution; melt stirring; nuclei; karbider; värmebehanding; gjutjärn; kullagerstål; gjutning; kylningshastighet; strukturanalys; nodulefördelning; smältrörelse; kärnor.; Metallurgical process science; Metallurgisk processvetenskap;

    Abstract : It is an established fact that segregation during casting affects the physical properties of carbon-based ferro alloys; this motivates the study of the segregation behaviour of carbon and carbide-forming solute elements. In this context, this thesis investigates two different situations: the effects of cooling rate and turbulence on the precipitation behaviour of the graphite nodules in nodular cast iron; the nature of carbide precipitation in a bearing steel grade and the effects of subsequent soaking on these carbides. READ MORE

  6. 19. Microstructure Evaluation and Wear-Resistant Properties of Ti-alloyed Hypereutectic High Chromium Cast Iron

    Author : Qiang Liu; Pär Jönsson; Keiji Nakajima; Niels Skat Tiedje; KTH; []
    Keywords : High Chromium Cast Iron; cooling rate; Ti addition; M7C3; TiC; carbides size distributions; volume fraction; heat treatment; microstructure; mechanical properties; wear resistance; statistics of extreme values SEV ; maximum carbides size.;

    Abstract : High chromium cast iron (HCCI) is considered as one of the most useful wear resistance materials and their usage are widely spread in industry. The mechanical properties of HCCI mainly depend on type, size, number, morphology of hard carbides and the matrix structure (γ or α). READ MORE

  7. 20. Control of Wear-Resistance Properties in Ti-added Hypereutectic High Chromium Cast Iron

    Author : Qiang Liu; Pär Jönsson; Keiji Nakajima; José Tinoco; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High Chromium Cast Iron; cooling rate; Ti addition; M7C3; TiC; carbides size distributions; volume fraction; heat treatment; microstructure; mechanical properties; wear resistance;

    Abstract : High chromium cast iron (HCCI) is considered as one of the most useful wear resistance materials and their usage are widely spread in industry. The wear resistance and mechanical properties of HCCI mainly depend on type, size, number, morphology of hard carbides and the matrix structure (γ or α). READ MORE