Sökning: "count-rate performance"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden count-rate performance.

1. 1. Development of Neutron Emission Spectroscopy Instrumentation for Deuterium and Deuterium-Tritium Fusion Plasmas at JET

   Författare :Luca Giacomelli; Jan Källne; Thomas Sangster; Uppsala universitet; []
   Nyckelord :Nuclear physics; neutron spectroscopy; MPRu; TOFOR; JET; Radio frequency heating; Count rate; Kärnfysik;

   Sammanfattning : The study of high power fusion plasmas at the JET tokamak has been further enhanced through the development of instrumentation for neutron emission spectroscopy (NES) measurements. This has involved the upgrade of the magnetic proton recoil (MPR) spectrometer used for deuterium-tritium plasmas earlier so that the MPRu can now be also employed for deuterium (D) plasmas. LÄS MER

3. 2. Fundamental Studies on Direct Injection Nebulisers for Sample Introduction in ICP Spectrometry : Aerosol Properties, ICP Characteristics and Analytical Performance

   Författare :Daniel Goitom Asfaha; Wolfgang Frech; Ralph Edward Sturgeon; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ICP; ICP-MS; ICP-OES; sample introduction; DIHEN; Vulkan DIN; non-spectral interferences; noise power spectra; analytical precision; plasma diagnostic parameters; particle dynamic analysis PDA ; Analytical chemistry; Analytisk kemi;

   Sammanfattning : The performance of different types of nebulisers: Vulkan direct injection nebuliser (Vulkan DIN), direct injection high efficiency nebuliser (DIHEN), microconcentric nebuliser coupled to cyclonic or double pass spray chamber (MCN-C or MCN-DP, respectively) was investigated and compared when used for sample introduction to ICP-MS or ICP-OES. With ICP-OES, in axial viewing mode, intensity distributions across the radius of the plasma (radial intensity profiles) were determined for different spectral lines with Esum 1. LÄS MER

4. 3. Neutron monitoring based on the higher order statistics of fission chamber signals

   Författare :Zsolt Elter; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Campbelling mode; Filtered Poisson process; High order; Simulation; Neutron flux monitoring; Experiment; Fission chamber;

   Sammanfattning : The work in this thesis corresponds to the safety aspect of Generation IV nuclear systems. One of the safety aspects concerns the enhancement of the performance of the in-vessel on-line core monitoring with neutron flux measurements. LÄS MER

5. 4. Characterization and Energy Calibration of a Silicon-Strip Detector for Photon-Counting Spectral Computed Tomography

   Författare :Xuejin Liu; Mats Danielsson; Sarah E Bohndiek; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Medical Technology; Medicinsk teknologi;

   Sammanfattning : Multibin photon-counting x-ray detectors are promising candidates to be applied in next generation computed tomography (CT), whereby energy information from a broad x-ray spectrum can be extracted and properly used for improving image quality and correspondingly reducing radiation dose. A silicon-strip detector has been developed for spectral CT, which operates in photon-counting mode and allows pulse-height discrimination with 8 adjustable energy bins. LÄS MER

7. 5. A Segmented Silicon Strip Detector for Photon-Counting Spectral Computed Tomography

   Författare :Cheng Xu; Hans Bornefalk; Mats Danielsson; Ami Altman; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; photon counting; spectral computed tomography; silicon strip detector; ASIC; energy resolution; cadmium telluride; charge sharing; Monte Carlo simulation; synchrotron;

   Sammanfattning : Spectral computed tomography with energy-resolving detectors has a potential to improve the detectability of images and correspondingly reduce the radiation dose to patients by extracting and properly using the energy information in the broad x-ray spectrum. A silicon photon-counting detector has been developed for spectral CT and it has successfully solved the problem of high photon flux in clinical CT applications by adopting the segmented detector structure and operating the detector in edge-on geometry. LÄS MER