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Visar resultat 1 - 5 av 204 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Thermoelectric Measurements for Temperature Control of Robotic Friction Stir Welding

   Författare :Ana Catarina Ferreira Magalhães; Gunnar Bolmsjö; Jeroen De Backer; Jean Pierre Bergmann; Högskolan Väst; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Friction stir welding; Aluminium; Temperature measurements; Process control; Robotics; Geometrically complex components; Friktionsomrörningssvetsning; Aluminium; temperaturmätning; Processstyrning; Robotik; Geometriskt komplexa komponenter; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik;

   Sammanfattning : Friction stir welding (FSW) has undergone a rapid expansion in several industrial sectors such as in the aerospace, marine, railway and automotive sectors. Current industrial applications are mainly simple long straight welds, but there is a growth of interest in components with higher geometric complexity. LÄS MER

3. 2. Partial Discharges Studied with Variable Frequency of the Applied Voltage

   Författare :Hans Edin; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; diagnostic methods; partial discharges; phase resolved; variable frequency; dielectric spectroscopy; dielectric response; harmonics; insulation; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Sammanfattning : This thesis concerns partial discharge (PD) diagnostics withvariable frequency of applied voltage in the frequency range 1mHz - 400 Hz. The exploration of a new type of spectroscopythat combines partial discharge analysis and dielectricresponse is demonstrated. LÄS MER

4. 3. Cardiorespiratory function of euryhaline teleosts - Regulatory mechanisms, effects of warming and costs of osmoregulation

   Författare :Daniel Morgenroth; Göteborgs universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; salinity; temperature; cardiac; vascular; gastrointestinal; acclimation; growth;

   Sammanfattning : Teleost fishes have colonized almost every aquatic habitat on earth and exhibit adaptations that allow them to thrive in environments with very diverse physico-chemical properties. One fundamental environmental variable in aquatic ecosystems is salinity, as most fish species are only able to tolerate a narrow range of salinities. LÄS MER

5. 4. Persistent organic pollutants in the atmosphere - spatial and temporal variations

   Författare :Cecilia Backe; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; tropical and temperate regions; global transport; temperature; latitudinal fractionation; fugacity; soil organic matter; soil-air exchange; washout ratio; rain; precipitation; atmosphere; spatial and temporal variations; DDT; PCB; persistent organic pollutants; polychlorinated biphenyls; Environmental chemistry; Miljökemi; Ecology; Ekologi; Chemistry; Kemi;

   Sammanfattning : In these thesis I have studied the spatial and temporal variations of PCBs in the atmosphere and in precipitation in southern Sweden. Further, soil-air exchange processes of PCBs were investigated. Finally, the long-range transport of PCBs and DDT was studied in the Baltic Sea region and in a tropical vs. a temporal region. LÄS MER

7. 5. Investigation of [N-X-N]+ and [N-C-N]+ complexes in solution : Exploring Geometry, Stability and Symmetry

   Författare :Alavi Karim; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; three center four electron; halonium; carbenium; carbonium; pentavalent; symmetry; NMR; variable temperature; counterion; isotopic perturbation of equilibrium;

   Sammanfattning : Halogen bonding is a weak interaction. In this thesis the three center four electron halogen bond, [N−X−N]+, has been studied. The lighter halogens form highly unstable halonium ions that are reactive towards nucleophiles and their complexes were therefore investigated at low temperatures. LÄS MER