Experiments to measure (i) the reactivity of lithium peroxide and lithium oxide in ambient air as a function of relative humidity and reactant particle size, (ii) the solubility of lithium hydroxide and lithium hydroxide monohydrate in three alcohols, namely methanol, ethanol and 1 and 2-propanol, as a function of time and temperature, (iii) the efficiency of the production of lithium peroxide in alcohol medium as a function of the concentration of LiOH.H 2O in methanol, the concentration of hydrogen peroxide, the kind of alcohol, the kind of feed material, and temperature and the time of mixing, (iv) the analysis of the precipitates, (v) the temperature of the precipitate decomposition in isothermal and non-isothermal conditions in ambient and neutral conditions as function of time, (vi) the activation energy of the precipitate decomposition, (vii) the temperature of the lithium peroxide decomposition in isothermal and non-isothermal conditions as function of time and (viii) the activation energy of lithium peroxide decomposition were performed. / The purpose of the study was to gather the data necessary to evaluate the production of lithium peroxide, Li2O2, and subsequently lithium oxide, Li2O, to be used as a feed for a silicothermic reduction process for the production of metallic lithium. The proposed basis for the production of Li2O2 was the conversion of lithium hydroxide or lithium hydroxide monohydrate by hydrogen peroxide in an alcohol medium. Alcohols were chosen because they are members of a class of non-aqueous solvents that can selectively dissolve the anticipated contaminants while precipitating the desired products. / It was found that the addition of hydrogen peroxide to alcohol solutions containing lithium hydroxide monohydrate resulted in the formation of lithium peroxide as lithium hydroperoxidate trihydrate with eight adduct molecules of methanol, i.e., Li2O2•H2O 2•3H2O•8CH3OH and involved the peroxide group transfer. The optimum conditions for the production of lithium peroxide were found to be (i) the least water concentration in the system (ii) the use of the temperature lower than ambient temperature and (iii) fast separation of the precipitate and raffinate to prevent dissociation of the precipitate or dissolving into the raffinate. / The high solubility of LiOH.H2O and at the same time the low solubility of Li2CO3 and of Li2O2 in methanol resulted in selection of methanol as the best alcohol of those studied for the proposed method of Li2O2 production. It also yielded high purity lithium peroxide. The production of Li2O 2 using H2O2 (35 %wt) required an excess of hydrogen peroxide equal to 2.6 times the stoichiometric amount. / The thermal decomposition of the lithium hydroperoxidate trihydrate precipitate started with the rejection of the adduct methanol molecules, followed by co-evolution of H2O and H2O2 from the resulting Li 2O2•H2O2•H2O. The activation energy of the decomposition reaction of the precipitate was measured as 141 kJ/mol. At temperatures greater than 200°C, lithium peroxide was found to be very reactive with atmospheric air. However, in an argon atmosphere, it rapidly decomposed losing the majority of the oxygen atoms, followed by the gradual slow diffusion of oxygen gas absorbed on the lithium oxide.

No description available.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 148-156).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

This thesis describes experimental methods, including in situ X-ray diffraction, especially suited to the study of lithium intercalation systems,and discusses the interpretation of the results obtained in a study of Li[sub=x]TiS₂. A rigid plate and spring model of layered intercalation systems is developed and is used to investigate the role of lattice expansion and elastic energy in layered intercalation compounds. When the elastic energy, calculated using the spring and plate model, is included in the Hamiltonian of a three dimensional lattice gas model for Li[sub=x]TiS₂ good agreement between the experimental results and the theoretical predictions are obtained. Staging, not lithium ordering, is identified as the dominant physical mechanism in Li[sub=x]TiS₂. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

No description available.

Thesis (Ph. D.)--State University of New York at Binghamton, Department of Chemistry, 2007. / Includes bibliographical references.

by Li, Tsui Kiu = 納米鋁酸鋰網絡增強的鋁基複合材料的製造和表徵 / 李翠翹. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Li, Tsui Kiu = Na mi lü suan li wang luo zeng qiang de lü ji fu he cai liao de zhi zao he biao zheng / Li Cuiqiao. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Table of contents --- p.vi / List of tables --- p.ix / List of figures --- p.xii / Chapter Chapter 1. --- Introduction / Chapter 1.1. --- Metal matrix composites (MMCs) --- p.1-2 / Chapter 1.1.1. --- Introduction --- p.1-2 / Chapter 1.1.2. --- Aluminum-based metal matrix composites (Al-MMCs) --- p.1-2 / Chapter 1.1.3. --- Applications of MMCs --- p.1-3 / Chapter 1.1.3.1. --- Automotive applications --- p.1-3 / Chapter 1.1.3.2. --- Aerospace applications --- p.1-4 / Chapter 1.1.4. --- Fabrication methods of metal matrix composites --- p.1-5 / Chapter 1.1.4.1. --- Stir casting --- p.1-5 / Chapter 1.1.4.2. --- Liquid metal infiltration --- p.1-5 / Chapter 1.1.4.3. --- Powder metallurgy --- p.1-6 / Chapter 1.1.4.4. --- The ex-situ sintering method --- p.6 / Chapter 1.1.4.5. --- The in-situ sintering method --- p.1-7 / Chapter 1.2. --- The Al-γ-LiA102 MMC --- p.1-7 / Chapter 1.2.1. --- Lithium aluminate (LiA102) --- p.1-8 / Chapter 1.2.2. --- Applications ofγ-LiA102 --- p.1-8 / Chapter 1.2.2.1. --- Ceramic matrices in molten carbonate fuel cell (MCFC) --- p.1-8 / Chapter 1.2.2.2. --- Tritium breeder materials in nuclear fusion reactors --- p.1-9 / Chapter 1.2.3. --- Fabrication methods ofγ-LiA102 --- p.1-10 / Chapter 1.2.3.1. --- Solid state reaction methods --- p.1-10 / Chapter 1.2.3.2. --- Sol-gel methods --- p.1-11 / Chapter 1.2.3.3. --- Hydrothermal treatment --- p.1-13 / Chapter 1.2.3.4. --- Ultrasonic Spray Pyrolysis --- p.1-13 / Chapter 1.2.3.5. --- The templated wet-chemical process --- p.1-13 / Chapter 1.2.3.6. --- Tape-casting --- p.1-14 / Chapter 1.2.3.7. --- Combustion Synthesis --- p.1-14 / Chapter 1.3. --- Previous works --- p.1-15 / Chapter 1.4. --- Current works --- p.1-16 / Chapter 1.5. --- Thesis layout --- p.1-17 / References / Chapter Chapter 2. --- Methodology and Instrumentation / Chapter 2.1. --- Introduction --- p.2-2 / Chapter 2.2. --- Powder Metallurgy --- p.2-2 / Chapter 2.3. --- Fabrication methods --- p.2-3 / Chapter 2.3.1. --- Tube furnace sintering --- p.2-3 / Chapter 2.3.2. --- Arc melting --- p.2-4 / Chapter 2.3.3. --- Annealing --- p.2-5 / Chapter 2.3.4. --- Sodium hydroxide etching --- p.2-5 / Chapter 2.4. --- Characterization methods --- p.2-6 / Chapter 2.4.1. --- Thermal analysis - Differential thermal analysis (DTA) --- p.2-6 / Chapter 2.4.2. --- Physical property analysis - Thermomechanical analyzer (TMA) --- p.2-6 / Chapter 2.4.3. --- Physical property analysis - The Archimedes' method --- p.2-7 / Chapter 2.4.4. --- Physical property analysis-Surface area and porosimetry analyzer --- p.2-8 / Chapter 2.4.5. --- Physical property analysis - Microhardness test --- p.2-9 / Chapter 2.4.6. --- Microstructural analysis - Scanning electron Microscopy (SEM) --- p.2-9 / Chapter 2.4.7. --- Surface morphology analysis - Atomic Force Microscopy (AFM) --- p.2-10 / Chapter 2.4.8. --- Phase determination - X-ray Diffractometry (XRD) --- p.2-11 / References / Chapter Chapter 3. --- Al-y-LiA102 MMC samples prepared by arc-melting / Chapter 3.1. --- Introduction --- p.3-2 / Chapter 3.2. --- Experimental details --- p.3-3 / Chapter 3.3. --- XRD analysis --- p.3-4 / Chapter 3.4. --- Microstructures --- p.3-5 / Chapter 3.5. --- NaOH etching time effects --- p.3-5 / Chapter 3.6. --- The 2-minute-etched sample --- p.3-6 / Chapter 3.7. --- Physical properties analysis --- p.3-7 / Chapter 3.7.1. --- Apparent density --- p.3-7 / Chapter 3.7.2. --- Microhardness --- p.3-7 / Chapter 3.7.3. --- BET analysis --- p.3-8 / Chapter 3.8. --- Formation mechanism ofγ-LiA102 network --- p.3-9 / Chapter 3.9. --- Effects ofLi20 contents --- p.3-10 / Chapter 3.9.1. --- Effects of Li2O contents on structure and compositions of MMCs --- p.3-10 / Chapter 3.9.2. --- Effects of Li2O- contents on coefficient of thermal expansion (CTE) --- p.3-11 / Chapter 3.10. --- Conclusions --- p.3-12 / References / Chapter Chapter 4. --- Al-y-LiAlO2 MMCs samples prepared by furnace sintering / Chapter 4.1. --- Introduction --- p.4-2 / Chapter 4.2. --- Experimental details --- p.4-2 / Chapter 4.3. --- The effects of sintering temperature --- p.4-3 / Chapter 4.3.1. --- Microstructures --- p.4-3 / Chapter 4.3.2. --- XRD analysis --- p.4-4 / Chapter 4.4. --- Prolonged NaOH etching --- p.4-5 / Chapter 4.5. --- Effects of annealing temperature --- p.4-7 / Chapter 4.6. --- DTA analysis of over-etched sample --- p.4-7 / Chapter 4.7. --- Thermal stability of the as-synthesized γ-LiA1O2 powders --- p.4-8 / Chapter 4.8. --- Conclusions --- p.4-9 / References / Chapter Chapter 5. --- Y-LiA1O2 pellets / Chapter 5.1. --- Introduction --- p.5-2 / Chapter 5.2. --- Experimental details --- p.5-2 / Chapter 5.3. --- Pellets fabricated by method 1 --- p.5-3 / Chapter 5.4. --- CTE and volume fraction of MMCs --- p.5-4 / Chapter 5.5. --- Pellets fabricated by method II --- p.5-5 / Chapter 5.6. --- Comparisons of γ-LiA1O2 fabricated by method I and method II --- p.5-6 / Chapter 5.7. --- Conclusions --- p.5-7 / References / Chapter Chapter 6. --- Conclusions and future works / Chapter 6.1. --- Conclusions --- p.6-2 / Chapter 6.2. --- Suggestions for future work --- p.6-3 / Chapter 6.2.1. --- Stability test of y-LiA1O2 in molten carbonates --- p.6-3 / Chapter 6.2.2. --- Investigation of the pore size distribution of γ-LiAIO2 network --- p.6-4 / Chapter 6.2.3. --- Fabrication of Al-γ-LiA1O2 MMC by hot isotatic pressing --- p.6-4 / Chapter 6.2.4. --- Mechanical tests --- p.6-4 / Chapter 6.2.5. --- Development of gas sensors --- p.6-5 / References

The research in this project was directed, firstly towards gaining an understanding of the effect excited-state absorption (ESA) has on gain and lasing in broadly tunable Ce:LiLuF lasers and secondly towards the development of Ce:LiLuF lasers suitable for spectroscopic applications. Detailed measurements of the single-pass, small-signal gain in Ce:LiLuF were undertaken, with a gain coefficient as high as 30±1 cm^-1 at 309 nm, with an absorbed pump fluence of 0.46 Jcm^-2. Further, the ESA in Ce:LiLuF at 261 nm and 349 nm was measured. Using both the gain and ESA results in a computer model, the effective gain cross-sections at 309 nm and 327 nm and the ESA cross-sections at 261 nm, 309 nm, 327 nm and 349 nm were determined. The ESA cross-sections were found to be of the order of 10^-18 cm². The effective gain cross-section in Ce:LiLuF was found to increase with decreasing temperature. This was proposed to arise from a decrease in the ESA cross-section with decreasing temperature in the Ce:LiLuF. An in-depth parametric study of Ce:LiLuF laser operation and tunability was undertaken. The results of these studies, together with computer modelling, enabled the importance of ESA and other effects on lasing to be established. In particular, the gain competition effects and ESA were found to lead to inefficient laser operation unless σ-polarised lasing was suppressed. With polarisation selection, efficient operation was obtained, with continuous tunability between 305 nm - 335 nm. Narrow bandwidth operation of Ce:LiLuF for use in OH radical detection in the atmosphere was investigated. Narrow bandwidth operation was achieved for the first time in Ce:LiLuF using a Eittrow grating with a telescopic and prism beam expansion system. Tunable lasing between 306.5 nm and 311.5 nm was obtained, with a spectral bandwidth of 0.7 cm^-1. Finally, highly efficient Ce:LiLuF lasing was achieved with a new all-solid-state, 289 nm frequency-quadrupled Raman-shifted Nd:YAG laser. Slope efficiencies as high as 62±3% were achieved. This slope is believed to be the highest obtained in any cerium laser to date. The IR-to-UV conversion efficiency was 0.41% and the UV-to-UV conversion efficiency was 41%. These high efficiencies were attributed to high pump beam quality and good mode matching.