The series of projects described in this dissertation was stimulated by the discovery of high temperature superconductivity. Our goal was to develop useful applications which would be competitive with the current state of technology. The high-{Tc} microbolometer was developed into the most sensitive direct detector of millimeter waves, when operated at liquid nitrogen temperatures. The thermal boundary resistance of thin YBa{sub 2}Cu{sub 3}0{sub 7-{delta}} films was subsequently measured and provided direct evidence for the bolometric response of high-{Tc} films to fast (ns) laser pulses. The low-{Tc} microbolometer was developed and used to make the first direct measurements of the frequency dependent optical efficiency of planar lithographed antennas. The hot-electron microbolometer was invented less than a year prior to the writing of this dissertation. Our analysis, presented here, indicates that it should be possible to attain up to two orders of magnitude higher sensitivity than that of the best available direct detectors when operated at the same temperature. The temperature readout scheme for this device could also be used to measure the intrinsic interaction between electrons and phonons in a metal with a sensitivity that is five orders of magnitude better than in previous measurements. Preliminary measurements of quasiparticle trapping effects …

The formation constants for the reactions PuO{sub 2}{sup +} + H{sub 2}O = PuO{sub 2}(OH) + H{sup +} and PuO{sub 2}{sup +} + CO{sub 3}{sup 2} = PuO{sub 2}(CO{sub 3}){sup {minus}} were determined in aqueous sodium perchlorate solutions by laser-induced photoacoustic spectroscopy. The molar absorptivity of the PuO{sub 2}{sup +} band at 569 nm decreased with increasing hydroxide concentration. Similarly, spectral changes occurred between 540 and 580 nm as the carbonate concentration was increased. The absorption data were analyzed by the non-linear least-squares program SQUAD to yield complexation constants. Using the specific ion interaction theory, both complexation constants were extrapolated to zero ionic strength. These thermodynamic complexation constants were combined with the oxidation-reduction potentials of Pu to obtain Eh versus pH diagrams. 120 refs., 35 figs., 12 tabs.