Sökning: "Tracer experiments"

Visar resultat 1 - 5 av 61 avhandlingar innehållade orden Tracer experiments.

  1. 1. Calibration and quality assessment of DESCARTES : grabsampler for stratospheric tracers

    Författare :Johan Arvelius; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Adsorption; Balloon; Carboxen; CFC; Chloro-Fluoro Carbon; Grab sampling; Halocarbon; Molecular sieve; Stratospheric tracer; Tracer; Adsorption; Ballong; Carboxen; CFC; Halogeniserade kolväten; Klor-Flourkarbon; Spårgas; Stratosfärisk spårgas; Space physics; Rymdfysik;

    Sammanfattning : DESCARTES is a light-weight, balloon-borne grab sampler for stratospheric long-lived tracers developed at the University of Cambridge. 33 flights have been performed with two versions of the instrument at northern latitudes by the DESCARTES team at the Swedish Institute of Space Physics (IRF) in Kiruna during the years 1997-2000. LÄS MER

  3. 2. Water density impact on water flow and mass transport in rock fractures

    Författare :Helen Winberg-Wang; Longcheng Liu; Ivars Neretnieks; Andrew Frampton; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tracer experiments; solute transport in fractured rock; advection-diffusion experiments; repositories; equivalent flowrate.; Spårämnesexperiment; ämnestransport i bergssprickor; advektion och diffusionsexperiment; slutförvar; ekvivalent flöde.;

    Sammanfattning : One way of taking care of spent nuclear fuel is to place it in a geological repository. In Sweden, a three-barrier system is planned. The system is based on encapsulating the fuel in copper canisters. These are surrounded by bentonite clay and buried under 500 m of bedrock. LÄS MER

  4. 3. 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

  5. 4. 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

  7. 5. Ventilation and window opening in schools, Experiments and Analysis

    Författare :Birgitta Nordquist; Avdelningen för Installations- och klimatiseringslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; heat exchanger efficiency; duct design; balancing; disturbance; tracer gas measurements; analytical model; window opening; single-sided ventilation; ventilation; schools; sensitivity analysis; Building construction; Byggnadsteknik;

    Sammanfattning : The objective of this thesis is to study the application of ventilation in schools buildings. A number of studies of the application of different forms of ventilation are presented. The main part of the thesis focuses on window opening in a classroom. Analytical models for calculation of the air change caused by window airing are proposed. LÄS MER