Search for dissertations about: "point defects"

Showing result 16 - 20 of 157 swedish dissertations containing the words point defects.

2. 16. Synthesis and Characterization of Functionalized Silica Mesoporous Crystals : Cationic Surfactant and Co-structure Directing Agent System

   Author : Lu Han; Osamu Terasaki; Viveka Alfredsson; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mesoporous silica; Template synthesis; Functionalization; Electron microscopy; Defects; Crystal growth; Catalysis; Inorganic chemistry; Oorganisk kemi; Structural Chemistry; strukturkemi;

   Abstract : This dissertation has been focused on the synthesis and characterization of novel functionalized silica mesoporous crystals by using cationic surfactant and co–structure directing agents (CSDA), the central concept of the synthesis method is to build proper organic/inorganic interactions by introducing CSDA into the synthesis system. By using cationic surfactant as template and anionic CSDA, carboxylic group functionalized mesoporous silicas were successfully synthesized. READ MORE

4. 17. Thermodynamic and kinetic properties of Fe-Cr and TiC-ZrC alloys from Density Functional Theory

   Author : Vsevolod Razumovskiy; Pavel Korzhavyi; Andrei Ruban; Malin Selleby; Sergei Dudarev; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; ab initio; first principles; point defects; vacancy clusters; alloys; steels; iron; carbides; diffusion; phase diagram; density functional theory; elastic constants; elastic properties; thermodynamic modelling;

   Abstract : The complete and accurate thermodynamic and kinetic description of any systemis crucialfor understanding and predicting its properties. A particular interest is in systemsthat are used for some practical applications and have to be constantly improved usingmodification of their composition and structure. READ MORE

5. 18. Understanding Defect Structures and Host-guest Interactions in Metal-organic Frameworks

   Author : Kang Zhengzhong; Yaoquan Tu; Lars Ojamäe; KTH; []
   Keywords : metal-organic framework; defects; host-guest; molecular dynamics simulation; Teoretisk kemi och biologi; Theoretical Chemistry and Biology;

   Abstract : Metal-organic frameworks (MOFs) represent a class of crystalline porous materials with prospective applications in molecular capture, separation, storage and catalysis. It has been discovered that there exist various structural defects in MOFs, which can have dramatic impact on their properties. READ MORE

6. 19. Modeling defect structure evolution in spent nuclear fuel container materials

   Author : Arash Hosseinzadeh Delandar; Pavel Korzhavyi; Rolf Sandström; Konstantin Khromov; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cast iron insert; First principles calculations; Point defects; Effective interaction energy; Late blooming phase; Dislocation dynamics; High strain rate deformation; Single-crystal copper; Copper canister; Creep; Glide; Teknisk materialvetenskap; Materials Science and Engineering;

   Abstract : Materials intended for disposal of spent nuclear fuel require a particular combination of physical and chemical properties. The driving forces and mechanisms underlying the material’s behavior must be scientifically understood in order to enable modeling at the relevant time- and length-scales. READ MORE

7. 20. On the defective origin of conductive and structural properties of oxides: insights from first principles

   Author : Anders Lindman; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; point defects; thermodynamic modeling; proton conductors; oxyhydrides; density-functional theory; BaZrO3; polarons; grain boundaries; space charges; oxides;

   Abstract : Oxides are versatile materials with applications in many different research fields; especially those related to clean energy technologies, such as fuel cells, batteries and solar panels. Many functional properties of these materials derive from lattice imperfections, or defects, and a lot of effort has been put into fine tuning these materials by modifying their structure on the atomic scale. READ MORE