Novel unsaturated polymers have been synthesized and studied as precursors to silicon carbide and third order nonlinear optical materials. X ray structures were obtained. Kinetic and mechanistic studies of the unique thermal isomerization of dimethylenedisilacyclobutane to a carbene were conducted.

The magnetic properties related to the following high temperature superconductors were measured utilizing a Faraday magnetometer: BaCuO{sub 2+x}, La{sub 2} CuO{sub 4}, Sr{sub 2} RhO{sub 4}, Sr{sub 2} VO{sub 4}, and Sr{sub 2} CuO{sub 3}. Neutron diffraction, magnetic susceptibility, and heat capacity measurements are discussed.

Electrical conductance has been measured in-situ in two dimensions in the Ag/Si(111) system as a function of incident adatom flux rate with a 4-probe method. A conductance study in a 3-D conical structure was also made using field emission. For the 2-D study, the origin of conduction is still unclear, as transport by percolating Ag clusters and conduction through the substrate lvia electrons from the film have both been suggested. Experiments varying the flux rate were conducted to decide between the two. Smoother films are expected at lower growth rates which would result in faster drops in the 4-probe voltage; however the 4-probe voltage vs deposition time for various flux rates collapse into a universal curve which indicates that the morphology is not relevant and supports through the substrate. In the 3-D conductance study, a single, lateral micromachined W protrusion on a silica substrate is examined to identify the factors controlling emission in micromachined structures. The I-V characteristics and emission pattern indicate that miniprotrusions of a few hundred Angstroms, much smaller than the nominal radius of the tip, exist on the tip and are responsible for the emission. Adsorption-desorption events from the background environment are the cause of large fluctuations …

Excellent separations of metal ions can be obtained very quickly by capillary electrophoresis provided a weak complexing reagent is incorporated into the electrolyte to alter the effective mobilities of the sample ions. Indirect photometric detection is possible by also adding a UV-sensitive ion to the electrolyte. Separations are described using phthalate, tartrate, lactate or hydroxyisobutyrate as the complexing reagent. A separation of twenty-seven metal ions was achieved in only 6 min using a lactate system. A mechanism for the separation of lanthanides is proposed for the hydroxyisobutyrate system.

Mo{sub 5}Si{sub 3} shows promise as a high temperature creep resistant material. The high temperature oxidation resistance of Mo{sub 5}Si{sub 3} has been found to be poor, however, limiting its use in oxidizing atmospheres. Undoped Mo{sub 5}Si{sub 3} exhibits mass loss in the temperature range 800{degrees}-1200{degrees}C due to volatilization of molybdenum oxide, indicating that the silica scale does not provide a passivating layer. The addition of boron results in protective scale formation and parabolic oxidation kinetics in the temperature range of 1050{degrees}-1300{degrees}C. The oxidation rate of Mo{sub 5}Si{sub 3} was decreased by 5 orders of magnitude at 1200{degrees}C by doping with less than two weight percent boron. Boron doping eliminates catastrophic {open_quote}pest{close_quote} oxidation at 800{degrees}C. The mechanism for improved oxidation resistance of boron doped Mo{sub 5}Si{sub 3} is due to scale modification by boron.