No description available.

No description available.

No description available.

The Infrared absorption of a single crystal of portlandite, over a temperature range from room temperature to below the melting point of hydrogen, was studied with both polarized and unpolarized radiation. The apparatus and experimental techniques are described, and the results and their significance in relation to earlier experimental work on the crystal structure of portlandite are discussed. / Thesis / Master of Science (MS)

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No description available.

New optical designs have necessitated using refractive index data that is accurate to the third and fourth decimal points. Prism coupling refractometry could be attractive for this task because of a combination of factors. It allows for a direct assessment of the refractive index like interferometry or the minimum deviation method while being quick and convenient, like Kramers-Krönig analysis and spectroscopic ellipsometry. However, the accuracy, precision, and repeatability of this technique have not been revisited recently in the literature. This thesis seeks to identify the critical features of this technique that define its uncertainties and then provides some initial improvements to this system. The improvements explored are hardware-based and incorporate a novel approach to fitting this data. The resulting error budget defined by this strategy increases the measured precision, taking the first step towards making the method a standard metrology technique suitable for the shop floor.

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A sample of 170 sources from the IRAS Point Source Catalog (PSC) having / b / ≥ 40°, 100μm flux F₄ ≥ 2.5 Jy, and upper limit fluxes at 12, 25 and 60μm was studied on POSS and ESO photographic plates. 151 of these sources are identified as 'infrared cirrus,' thirteen as galaxies, and one as a planetary nebula; four sources lie in the Small Magellanic Cloud (SMC), and the remaining source is Saturn. Accurate infrared fluxes were obtained for 29 cirrus sources, the galaxies, and the planetary nebula. The colors of the cirrus sources support the hypothesis that the radiation is coming from a mixture of large, cool grains and Polycyclic Aromatic Hydrocarbons (PAHs), with large variation in relative abundances. Optical colors and surface brightness were obtained for one cirrus cloud using data from the CCD Transit Instrument on Kitt Peak.

Yeung Shun-hin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 52-54). / Abstracts in English and Chinese. / TITLE PAGE --- p.i / THESIS COMMITTEE --- p.ii / ABSTRACT (ENGLISH) --- p.iii / ABSTRACT (CHINESE) --- p.iv / ACKNOWLEDGEMENTS --- p.v / TABLES OF CONTENTS --- p.vi / LIST OF FIGURES --- p.viii / LIST OF TABLES --- p.x / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Computer-controlled Data Acquisition and Frequency Calibration System for a Ti: sapphire laser spectrometer --- p.3 / Chapter Section 2A --- Motivation and Overview --- p.3 / Chapter Section 2B --- The Hardware --- p.5 / Chapter Section 2C --- The Program --- p.12 / Chapter Section 2D --- Summary --- p.27 / Chapter Chapter 3 --- Cavity Enhanced Absorption Spectroscopy Using Phase-Sensitive Detection --- p.28 / Chapter Section 3A --- Motivation --- p.28 / Chapter Section 3B --- Cavity ring-down technique: the background --- p.29 / Chapter Section 3C --- Cavity enhanced absorption spectroscopy: a historical review --- p.34 / Chapter Section 3D --- Experimental Apparatus --- p.37 / Chapter Section 3E --- Results of Performance tests --- p.41 / Chapter Section 3F --- Applications --- p.45 / Chapter Section 3G --- Summary --- p.49 / Chapter Chapter 4 --- Concluding Remarks --- p.50 / REFERENCES --- p.52