SPECTROSCOPIC STUDIES OF ALKALI METAL ATOMS ISOLATED IN LOW TEMPERATURE MATRICES; LASER-INDUCED FLUORESCENCE STUDIES OF BIOLOGICAL TISSUES
| Autor: | CHIN, ROBERT C. |
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| Jazyk: | angličtina |
| Rok vydání: | 1987 |
| Předmět: | |
| Druh dokumentu: | Diplomová práce |
| Popis: | The interpretation of absorption spectra of metal atoms isolated in rare gas matrices has long been debated. In our studies we have observed the UV/Vis spectra of lithium/xenon and sodium/xenon matrices. A model is proposed to interpret our results. This model employs a BEBO explanation of the interactions of the metal atom in the rare gas crystal. By establishing the interaction potentials of the metal atom in the crystal, it is possible to calculate overlap integrals and thereby calculate an absorption envelope of Franck-Condon factor sticks. An analytical lineshape for the phonon vibrational wing and the zero phonon line was employed to calculate a theoretical spectrum. This model may be employed in the understanding of impurity atoms in solid rate gas matrices. The second topic involves the employment of laser radiation as a diagnostic tool in the discrimination of diseased and normal tissues. Laser excitation by an Argon ion laser produced characteristic autofluorescences between malignant and normal lung tissues. Three emission bands in the range of 22000 to 12000 cm$\sp{-1}$ were observed. By applying statistical analysis it is established that the method may be utilized to diagnose malignant tumors in and around the lung. Other tissues studied were atherosclerotic and normal coronary arteries. These tissue types also showed a very characteristic autofluorescence signature. This distinction may be utilized to determine the extent of disease in coronary arteries. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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