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Visar resultat 1 - 5 av 6 avhandlingar som matchar ovanstående sökkriterier.

1. 1. On-line Mobile in situ Gamma Spectrometry

   Författare :Thomas Hjerpe; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiobiologi; Kärnfysik; Nuclear physics; radiation protection.; 137Cs; peak-to-valley method; depth distribution; orphan source search; orphan sources; emergency preparedness; mobile gamma spectrometry; nuclear accidents; Nuclear medicine; radiobiology; Nukleärmedicin;

   Sammanfattning : Mobile in situ gamma spectrometry is an important instrument in the emergency preparedness for nuclear accidents. This work contributes through the development of strategies and analysis methods for two applications: an on-line search for gamma-emitting orphan sources and on-line estimation of the depth distribution of 137Cs. LÄS MER

3. 2. Methods for localizing and quantifying radionuclide sources and deposition using in situ gamma spectrometry : Critical review of the peak-to-valley method based on experimental studies and applications in Georgia and Japan

   Författare :Karl Östlund; Malmö Medicinsk strålningsfysik; []
   Nyckelord :In situ gamma spectrometry;

   Sammanfattning : This thesis describes investigations made on mobile and stationary gammaspectrometry made both under laboratory conditions and in situ. The objective hasbeen to identify and quantify radionuclides in the form of point sources,contamination and widespread deposition in situations where the measurementgeometry is not known beforehand. LÄS MER

4. 3. Design and fabrication of hidden hinge monocrystalline silicon micromirrors for maskless lithography

   Författare :Martin Bring; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; isotropic etching; LOCOS; micromirror; maskless lithography; chevron notch; low temperature transfer bonding; fracture toughness;

   Sammanfattning : Micromirror-based maskless lithography has recently received attention as an attractive candidate to tackle challenges associated with the continued de-vice scaling in the semiconductor industry. The micromirrors work by diffrac-tion and the requirements on planarity are very tough, e.g. peak-to-valley dif-ferences of a few nanometers. LÄS MER

5. 4. Magnesium Diboride (MgB2) and Ca-doped YBa2Cu3O7-? : Thin Films and Devices. Fabrication and Characterization

   Författare :Anayesu Malisa; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ca-doped YBa2Cu3O7-?; MgB2; bicrystal; superconductor; nanobridge; thin film; Josephson effect; Josephson junction;

   Sammanfattning : Magnesium diboride (MgB2) is a superconductor with an exceptionally high transition temperature, Tc, of 39 K. This work describes deposition of high quality and superconducting films of MgB2 for electronic applications. Experiments on Ca-doped YBa2Cu3O7-? films and fabrication of bicrystal Josephson junctions are also described. LÄS MER

7. 5. Methods for Characterisation of Pressing Die Surfaces

   Författare :Johan C Berglund; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finish milling; scale-sensitive fractal analysis; surface characterisation; polishing; functional correlation; : pressing dies; functional filtration; surface roughness; functional surface;

   Sammanfattning : Design and manufacture of dies and moulds is a critical aspect of many production systems since the manufacturing and try-out of new dies and moulds often is essential in determining the lead-time and quality of a new production system. In the automotive industry, many new car models are introduced each year and for each of these models, a new set of pressing dies has to be designed and manufactured. LÄS MER