Sökning: "electron structure"

Visar resultat 6 - 10 av 1292 avhandlingar innehållade orden electron structure.

1. 6. 3D Electron crystallography : Real space reconstruction and reciprocal space tomography

   Författare :Daliang Zhang; Xiaodong Zou; Douglas L. Dorset; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electron crystallography; Electron microscopy; Porous materials; Chemistry; Kemi; Structural Chemistry; strukturkemi;

   Sammanfattning : Electron crystallography is an important technique for studying micro- and nano-sized materials. It has two important advantages over X-ray crystallography for structural studies: 1) crystals millions of times smaller than those needed for X-ray diffraction can be studied; 2) it is possible to; focus the electrons to form an image. LÄS MER

3. 7. Structure Determination and Prediction of Zeolites : A Combined Study by Electron Diffraction, Powder X-Ray Diffraction and Database Mining

   Författare :Peng Guo; Xiaodong Zou; Christine Kirschhock; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; zeolites; rotation electron diffraction; structure determination; structure prediction; strong reflections approach; Inorganic Chemistry; oorganisk kemi;

   Sammanfattning : Zeolites are crystalline microporous aluminosilicates with well-defined cavities or channels of molecular dimensions. They are widely used for applications such as gas adsorption, gas storage, ion exchange and catalysis. The size of the pore opening allows zeolites to be categorized into small, medium, large and extra-large pore zeolites. LÄS MER

4. 8. 3D Electron Microscopy Methods and Applications : Structures from Atomic Scale to Mesoscale

   Författare :Taimin Yang; Xiaodong Zou; Grüne Tim; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 3D Electron microscopy; continuous rotation electron diffraction; structure determination; data quality; electron tomography; mesoporous materials; zeolites; Inorganic Chemistry; oorganisk kemi;

   Sammanfattning : The crystal structure determines the physical properties of a material. The structure can be analysed at different levels, from atomic level, mesoscale level, all the way up to the macroscale level. LÄS MER

5. 9. A journey towards complete structure determination of zeolites by electron crystallography methods

   Författare :Elina Kapaca; Xiaodong Zou; Philippe Boullay; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electron crystallography; Zeolites; Structure determination; Rotation electron diffraction; Continuous rotation electron diffraction; Disorder; Inorganic Chemistry; oorganisk kemi;

   Sammanfattning : Electron crystallography has recently become very successful for structural studies of materials with sub-micrometer sized crystals. In this thesis two major techniques have been applied for structure elucidation – 3-dimensional electron diffraction (3D ED) and high-resolution transmission electron microscopy (HRTEM) imaging. LÄS MER

7. 10. 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