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Visar resultat 1 - 5 av 212 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Synchrotron radiation studies of gas phase molecules : from hydrogen to DNA sugars

   Författare :Gemma Vall-llosera; Elisabeth Rachlew; Stacey Sorensen; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; KTH thesis; synchrotron radiation; gas phase; bio molecules; Atomic and molecular physics; Atom- och molekylfysik;

   Sammanfattning : This thesis summarises experimental results on the molecular spectroscopy of gas phase molecules excited by synchrotron radiation in the VUV and soft X-ray regions. We have used three different detection techniques, photon induced fluorescence spectroscopy, photoionisation mass spectroscopy and near edge X-ray absorption fine structure spectroscopy to study molecular deuterium, hydrogen sulphide, ammonia, methanol, pyridine, pyridazine, pyrimidine, pyrazine, s-triazine, and 2-deoxy-D-ribose, the last one also known as the DNA sugar. LÄS MER

3. 2. Heat Transfer and Energy Efficiency in Infrared Paper Dryers

   Författare :Magnus Pettersson; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; experimental; modelling; electricity; gas; efficiency; energy; drying; dryer; heat transfer; radiation; paper; infrared; IR; coating; Chemical technology and engineering; Kemiteknik och kemisk teknologi;

   Sammanfattning : Infrared (IR) dryers are widely used in the paper industry, mainly in the production of coated paper grades. The thesis deals with various aspects of heat transfer and energy use in infrared heaters and dryers as employed in the paper industry. Both gas-fired and electric IR dryers are considered and compared. LÄS MER

4. 3. Reducing Radon Gas Emissions in Concrete

   Författare :Magnus Döse; Johan Silfwerbrand; Franz Josef Maringer; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Radon gas; emissions; health; concrete; building materials; ionizing radiation; Betongbyggnad; Concrete Structures;

   Sammanfattning : Several compulsory regulations and recommendations regarding ionising radiation for building products have been introduced in recent years. Furthermore, industry-affiliated aggregate and concrete companies strive to implement environmental goals that should be fulfilled regarding building materials. LÄS MER

5. 4. New Efficient Detector for Radiation Therapy Imaging using Gas Electron Multipliers

   Författare :Janina Östling; Mats Danielsson; Anders Brahme; Fabio Sauli; Stockholms universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Portal imaging; Gas Electron Multiplier; Gas detector; Medical engineering; Medicinsk teknik;

   Sammanfattning : Currently film is being replaced by electronic detectors for portal imaging in radiation therapy. This development offers obvious advantages such as on-line quality assurance and digital images that can easily be accessed, processed and communicated. LÄS MER

7. 5. A Treatise on the Geometric and Electronic Structure of Clusters : Investigated by Synchrotron Radiation Based Electron Spectroscopies

   Författare :Andreas Lindblad; Olle Björneholm; Gunnar Öhrwall; Maxim Tchaplyguine; Paolo Milani; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cluster; nanoparticle; Heterogeneous; Homogeneous; Mixed; Cluster production methods; co-expansion; pick-up; doping; Cluster geometry; radial segregation; Interatomic Coulombic Decay; ICD; Auger electron spectroscopy; AES; X-ray photoelectron spectroscopy; XPS; Ultra-violet spectroscopy; UPS; Noble gas; Rare gas; Ne; Ar; Kr; Xe; Ammonia; NH3; Sulphur hexafluoride; SF6; MAX-lab; BESSY; Physics; Fysik;

   Sammanfattning : Clusters are finite ensembles of atoms or molecules with sizes in the nanometer regime (i.e. nanoparticles). This thesis present results on the geometric and electronic structure of homogeneous and heterogeneous combinations of atoms and molecules. LÄS MER