Characterization of control mesoporous glasses (CPGs) using positron annihilation lifetime spectroscopy (PALS) [Elektronische Ressource] / by Essmat Mahmoud Hassan Sayed Ahmed

Martin Luther University (MLU) Characterization of Control Mesoporous Glasses (CPGs) Using Positron Annihilation Lifetime Spectroscopy (PALS) Dissertation Submitted to the Faculty of Natural Sciences II Martin Luther University Halle-Wittenberg In Partial Fulfillment of the Requirements For the award of the Degree of Doctor of Natural Sciences (Physics) BY Essmat Mahmoud Hassan ‘Sayed Ahmed’ MSc. in Physics (2001) Born in: Suhag, Egypt 1974 Approvals: 1- Prof. Dr. R. Krause-Rehberg2- Prof. Dr. Helmut Föll3- Dr. habil Dirk Enke Halle/Saale, 5 October 2007 Verteidigungsdatum: 30.01.2008urn:nbn:de:gbv:3-000013180[http://nbn-resolving.de/urn/resolver.pl?urn=nbn%3Ade%3Agbv%3A3-000013180]Subject Abstract ….…………………………………………………………………………………….I Chapter 1: Principles of Positron Annihilation Spectroscopy 1 1.1. Introduction ……………………….……………………………………………………. 1 1.1.2. Positron and Positronium Physics ….….…………………………………………………. 1 1.1.3. Annihilation Process .…………………………………….. 3 1.2. Possible Sources of Positron …………………………………………………………… 5 1.3. Positron States in Matter ………..………………………………………………............ 6 1.4. Kinetics of Ps Formation and Lifetime Spectroscopy…..………………………............ 7 1.5. Principles of Positrons Annihilations in Solid …………………………………………. 11 1.6. Positron Annihilation Lifetime Spectroscopy (PALS) ……………………………….... 13 Chapter 2: Characterization of Porous 16 2.1. Introduction …………………………………………………………………………….