Thesis - Oztek_Muzaffer_T_200508_MA

2.2.2.1. Hydriding and Dehydriding Procedures ........................................... 30
2.2.2.2. Activation procedure......................................................................... 31
2.3. Sample Preparation ........................................................................................... 32
2.4. Sample characterization and Analysis .............................................................. 33
3. RESULTS AND DISCUSSIONS................................................................................. 35
3.1. Hydride Formers ............................................................................................... 35
3.1.1. Mg 2 Ni........................................................................................................ 36
3.1.2. VTiNi ........................................................................................................ 40
3.1.3. LaNi 5 ......................................................................................................... 44
3.1.3.1. Effect of Ball Milling........................................................................ 45
3.1.3.2. Effect of Thermal Activation............................................................ 46
3.1.3.3. Effects of Type of Mill, Milling Speed and Milling Atmosphere .... 48
3.1.3.4. Effect of Milling Time and Ball to Powder Ratio............................. 52
3.1.3.5. Dehydriding of LaNi 5 ....................................................................... 53
3.2. Aluminum in LaNi 5 ........................................................................................... 55
3.2.1. Interaction With Pure Hydrogen............................................................... 55
3.2.2. Hydrogen Uptake From Hydrogen – Helium Mixtures............................ 59
3.2.2.1. VTiNi ................................................................................................ 60
3.2.2.2. LaNi 5 ................................................................................................. 62
3.2.2.3. LaNi 5 with Al.................................................................................... 64
3.2.2.4. AuPd and Pt Coating on LaNi 5 ......................................................... 67
3.3. Parr Reactor ...................................................................................................... 70
3.4. U-Tube Hydriding Reactor ............................................................................... 74
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