Abstract: A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

Abstract: A second harmonic, optical generator is disclosed in which a laser diode produces an output pumping beam which is focused by means of a graded, refractive index rod lens into a rod of lasant material, such as Nd:YAG, disposed within an optical resonator to pump the lasant material and to excite the optical resonator at a fundamental wavelength. A non-linear electro-optic material such as MgO:LiNbO.sub.3 is coupled to the excited, fundamental mode of the optical resonator to produce a non-linear interaction with the fundamental wavelength producing a harmonic. In one embodiment, the gain medium and the non-linear material are disposed within an optical resonator defined by a pair of reflectors, one of which is formed on a face of the gain medium and the second of which is formed on a face of the non-linear medium. In another embodiment, the non-linear, electro-optic material is doped with the lasant ion such that the gain medium and the non-linear doubling material are co-extensive in volume.

Abstract: A monolithic phasematched harmonic generator is obtained by optically pumping an optically nonlinear lasant member having reflective faces defining the monolithic optical resonator. Phasematching is achieved, in one case, by inclining a totally internally reflective face of the resonator at a proper angle relative to other faces of the resonator to angularly separate and resonate lasant waves of the proper polarization. In a second case, a clad fiber resonator of optically nonlinear lasant material has its cladding arranged to guide and thus resonate only lasant waves of the correct polarization. In a third case, the optical nonlinear coefficient of the optically nonlinear lasant material is spatially modulated with a period equal to an odd integer number of coherence lengths, of the harmonic generation process, to obtain quasi-phasematched operation. Phasematched operation improves the efficiency of the harmonic generation process.

Abstract: Stabilized quadrivalent cation oxide electrolytes are employed in fuel cells at elevated temperatures with a carbon and/or hydrogen containing fuel anode and an oxygen cathode. The fuel cell is operated at elevated temperatures with conductive metallic coatings as electrodes and desirably having the electrolyte surface blackened. Of particular interest as the quadrivalent oxide is zirconia.