Sökning: "electron beam"

Visar resultat 11 - 15 av 451 avhandlingar innehållade orden electron beam.

1. 11. Taming of Oxygen in the Electron Microscope : Effects of High Energy Electron Irradiation on O2 and Oxides

   Författare :David Wahlqvist; NanoLund: Centre for Nanoscience; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Transmission electron microscope; Environmental transmission electron mircoscopy; Electron Beam damage; Oxidation; carbon black;

   Sammanfattning : Transmission electron microscopy (TEM) is an atomic resolution technique that allows for in depth analysis of the properties of different materials by passing high energy electrons through a thin sample and detecting how they are affected. However, due to the strong interaction between electrons and matter, the probability of the sample remaining unperturbed by the electron irradiation is small. LÄS MER

3. 12. Structure determination of beam sensitive crystals by rotation electron diffraction : the impact of sample cooling

   Författare :Fei Peng; Junliang Sun; Xiaodong Zou; Dag Nores; Ute Kolb; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; electron crystallography; rotation electron diffraction; structure determination; cooling; Inorganic Chemistry; oorganisk kemi;

   Sammanfattning : Electron crystallography is complementary to X-ray crystallography. Single crystal X-ray diffraction requires the size of a crystal to be larger than about 5 × 5 × 5 μm3 while a TEM allows a million times smaller crystals being studied. This advantage of electron crystallography has been used to solve new structures of small crystals. LÄS MER

4. 13. Electron energization in near-Earth space : Studies of kinetic scales using multi-spacecraft data

   Författare :Elin Eriksson; Andris Vaivads; Masahiro Hoshino; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetic reconnection; electron acceleration; electron heating; magnetosheath; magnetotail; magnetic nulls; Cluster; Magnetospheric MultiScale; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

   Sammanfattning : Plasma, a gas of charged particles exhibiting collective behavior, is everywhere in the Universe. The heating of plasma to millions of degrees and acceleration of charged particles to very high energies has been observed in many astrophysical environments. How and where the heating and acceleration occur is in many cases unclear. LÄS MER

5. 14. SURFACE PROPERTIES OF IMPLANTS MANUFACTURED USING ELECTRON BEAM MELTING

   Författare :Rebecca Klingvall Ek; Lars-Erik Rännar; Mikael Bäckström; Jaan Hong; Felicia Suska; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electron beam melting; blood coagulation; bone ingrowth; surface roughness; process parameters;

   Sammanfattning : This thesis summarizes the results concerning the manufacture of medical implants for bone replacement using electron beam melting (EBM) which is an additive manufacturing (AM) technology, and aims to satisfy the engineering needs for the medical functionality of manufacturing technology. This thesis has focused on some microscopic properties for surfaces and bone integration. LÄS MER

7. 15. A study on Electron Beam Melted Ti-6Al-4V

   Författare :Adnan Safdar; Hållfasthetslära; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ti-6Al-4V; Electron beam melting; Microstructures; Surface roughness; phase filed modelling.;

   Sammanfattning : The work presented in this dissertation is concerned with the microstructures and surface roughness of test slabs of Ti-6Al-4V produced by one of powder based Additive Manufacturing (AM) technique namely electron beam melting (EBM). The effects of process parameters of a EBM system and geometry factors of a EBM build such as slabs’ thickness and height etc. LÄS MER