Sökning: "Tracer"

Visar resultat 6 - 10 av 339 avhandlingar innehållade ordet Tracer.

1. 6. Some Aspects on Macroscopic Mixing in a Tundish

   Författare :Chao Chen; Anders Tilliander; Lage Jonsson; Pär Jönsson; Guoguang Cheng; Seppo Louhenkilpi; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; continuous reactor; tundish; tracer; macroscopic mixing; water model; CFD; turbulence models; inclusions removal; inclusions deposition; dynamic removal; Materials Science and Engineering; Teknisk materialvetenskap;

   Sammanfattning : Two aspects on macroscopic mixing in a continuous flow system – metallurgical tundish were studied. Specifically, 1) the first focus was on salt solution tracer mixing, which is important for tundish design from perspectives of tracer technology and Residence Time Distributions (RTD) as well as for the understanding of the macroscopic mixing in tundishes. LÄS MER

3. 7. Quantitative Tracer Based MRI Perfusion : Potentials and Limitations

   Författare :Arvid Morell; Atle Bjørnerud; Håkan Ahlström; Linda Knutsson; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MRI; Perfusion; Contrast agent; Relaxivity; Radiology; Radiologi;

   Sammanfattning : Tracer based MRI perfusion measurements is a clinically useful tool to assess regional distributions of tissue blood flow and volume. The method may be based on any of the three relaxation mechanisms T1, T1 and T2*, the latter denoted DSC-MRI being the most common. LÄS MER

4. 8. A Study on the Correlation between Ladle Glaze and Non-Metallic Inclusions in the Ladle Treatment

   Författare :Minho Song; Du Sichen; Jerome P. Downey; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; non-metallic inclusions; ladle treatment; ladle glaze; tracer; tool steel; viscosity; activity; modelling; Al2O3-CaO-MgO-SiO2 system; Materials science; Teknisk materialvetenskap;

   Sammanfattning : In the present thesis, the correlation between ladle glaze and non-metallic inclusions in the ladle treatment was studied. A number of industrial trials with full scale ladle and laboratory works were performed to investigate the inclusions in the ladle treatment. LÄS MER

5. 9. Gas Mixing in a Circulating Fluidised Bed Boiler

   Författare :Johan Sternéus; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; circulating fluidized bed; gas mixing; tracer; boiler; dispersion; scaling; turbulence; two-phase flow; fluidization;

   Sammanfattning : The present thesis is a study on the gas-mixing behaviour in a circulating fluidised bed (CFB) boiler. The aim is to describe how gas is spread in different regions of a CFB furnace and to explain variations in the mixing rate under different operating conditions. LÄS MER

7. 10. Imaging and Quantification of Brain Serotonergic Activity using PET

   Författare :Pinelopi Lundquist; Margareta Hammarlund-Udenaes; Per Hartvig; Gunnar Blomquist; Paul Cumming; Uppsala universitet; []
   Nyckelord :Pharmacokinetics Pharmacotherapy; Brain serotonin; Neurotransmitter release; Neurotransmitter synthesis; Positron emission tomography; Tracer validation; Tracer modelling; Farmakokinetik Farmakoterapi;

   Sammanfattning : This thesis investigates the potential of using positron emission tomography (PET) to study the biosynthesis and release of serotonin (5HT) at the brain serotonergic neuron. As PET requires probe compounds with specific attributes to enable imaging and quantification of biological processes, emphasis was placed on the evaluation of these attributes. LÄS MER