No description available.

Call number: LD2668 .T4 1956 H38 / Master of Science

Call number: LD2668 .T4 1962 W33

Call number: LD2668 .T4 1953 C69 / Master of Science

No description available.

published_or_final_version / abstract / toc / Physics / Master / Master of Philosophy

published_or_final_version / abstract / Physics / Master / Master of Philosophy

The research described in this dissertation conclusively demonstrates the superior qualitative and quantitative performance of spectroscopic systems which employ a new class of optical detectors--charge transfer device (CTD) detectors. An overview of the operation and characteristics of these detectors, as well as theoretical models predicting their performance are presented. The evaluation of a unique prototype single element CID detector, a commercially available linear CCD detector, and a prototype two-dimensional CCD detector are described. Outstanding characteristics include the ability of the single element CID to quantitate photon fluxes ranging over eleven orders of magnitude, a quantum efficiency of the linear CCD in excess of 90%, and a read noise of the two-dimensional CCD of under 5 electrons. In addition, the use of the linear CCD for molecular fluorescence spectroscopy is demonstrated. A direct comparison of CCD and CID detection for atomic emission spectroscopy using a custom echelle system is described. The second part of these investigations focus on the design of spectrometers compatible with the format of these multichannel detectors. While a large number of spectrometer designs exist, the spectrometer and detector combination which produces the highest possible signal-to-noise ratio (SNR) spectra for a given experimental system is almost always desired. The investigations into optimum spectrometer design have led to the use of a unique spatial interferometer system. The performance of a common path interferometer using a linear charge-coupled device detectors is presented and compared to conventional dispersive systems. The throughput, resolution, and other practical factors are discussed. The common path system has a much larger light gathering ability compared to dispersive systems; however, spatial interferometry suffers from the multiplex disadvantages encountered with other forms of UV/Vis interferometry. A unique crossed interferometric dispersive arrangement allows the simultaneous acquisition of the spectral information while greatly reducing these multiplex disadvantages. Preliminary work on the crossed interferometric system is presented demonstrating significant reduction of these multiplex disadvantages.

A Rutherford backscattering spectrometry facility has been designed and built at the University of Arizona. Initial calibration and testing has been carried out in order to accurately characterize the system and make it ready to perform reliable analyses. Also, an explanation of basic RBS principles has been presented to enable persons unacquainted with the technique to determine its applicability for various types of analytical problems. A method for determining the concentration profile of Ag in an SiO₂ matrix is carefully explained. Calculations derived from basic principles are demonstrated for this analysis and can be applied in a number of similar circumstances. Several other examples of analyses of utilizing various operating parameters are explained and illustrated. Some examples of unusual samples are shown to be feasible for analysis by this technique. RBS is shown to be a very useful analytical tool for a wide variety of samples. It has the capability of performing quantitative depth profiles without standards. The vast potential for its use by analytical chemists is demonstrated, and future improvements for this particular facility are discussed.

by Siu-kai Tse. / Bibliography: leaves 100-103 / Thesis (M.Ph.)--Chinese University of Hong Kong, 1984