Anthony F. Bernhardt
Electrochemical Sharpening of Field Emission Tips
U.S. Patent 5,891,321
April 6, 1999
A method for sharpening field-emitter tips by electroetching/ polishing. In gated field emitters, electron emission must be initiated at the lowest possible voltage. The composition of the emitter and the gate and the structure of the emitter gate are essential to low-voltage initiation. This method of sharpening the emitter tips uses the grid as a counter electrode in electroetching the emitters and can produce extremely sharp emitter tips and remove asperities and other imperfections in the emitters in relation to the specific grid hole in which the emitter resides. Emissions thus become more uniform among the emitters, and turn-on voltage is lowered.
Mark C. Hsiao, Bernard T. Merritt, Bernardino M. Penetrante, and George E. Vogtlin
Pre-converted Nitric Oxide Gas in Catalytic Reduction System
U.S. Patent 5,891,409
April 6, 1999
A two-stage catalyst composed of an oxidative first stage and a reductive second stage. The first stage is intended to convert nitrogen oxide to nitrogen dioxide in the presence of oxygen. The second stage serves to convert nitrogen dioxide to environmentally benign gases that include diatomic nitrogen, carbon dioxide, and water. By preconverting nitrogen oxide to nitrogen dioxide in the first state, the catalyst enhances the efficiency of the second stage for the reduction of environmentally harmful nitrogen compounds (NOx).
George E. Vogtlin, Bernard T. Merritt, Mark C. Hsiao, P. Henrik Wallman, and Bernardino M. Penetrante
Catalytic Reduction System for Oxygen-Rich Exhaust
U.S. Patent 5,893,267
April 13, 1999
Nonthermal plasma gas treatment is combined with selective catalytic reduction to enhance NOx reduction in oxygen-rich vehicle engine exhausts.
Kenneth E. Montgomery, Natalia P. Zaitseva, James J. DeYoreo, and Russell L. Vital
Device for Isolation of Seed Crystals during Processing of Solution
U.S. Patent 5,904,772
May 18, 1999
A device for isolating seed crystals during processing of solutions. The device enables a seed crystal to be introduced into the solution without exposing the solution to contaminants or to sources of drying and cooling. The device constitutes a seed protector that allows the seed to be present in the growth solution during filtration and overheating operations while at the same time preventing the seed from being dissolved by the undersaturated solution. When the solution processing has been completed and the solution cooled to near the saturation point, the seed protector is opened, exposing the seed to the solution and allowing growth to begin.
Michael D. Perry, Jerald A. Britten, Hoang T. Nguyen, and Bruce W. Shore
Multilayer Dielectric Diffraction Gratings
U.S. Patent 5,907,436
May 25, 1999
The method for designing and fabricating dielectric grating structures with high diffraction efficiency used in reflection or transmission. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described.
Harley M. Buettner, William D. Daily, Roger D. Aines, Robin L. Newmark, Abelardo L. Ramirez, and William H. Siegel
Electrode Wells for Powerline-Frequency Electrical Heating of Soils
U.S. Patent 5,907,662
May 25, 1999
An electrode well for use in powerline-frequency heating of soils for decontamination of the soil. Heating of soils enables the removal of volatile organic compounds from soil when utilized in combination with vacuum extraction. A preferred embodiment of the electrode well utilizes a mild steel pipe as the current-carrying conductor to at least one stainless steel electrode surrounded by a conductive backfill material, preferably graphite or steel shot. A covering is also provided for electrically insulating the current-carrying pipe. One of the electrode wells is utilized with an extraction well, which is under subatmospheric pressure to withdraw the volatile material, such as gasoline and trichloroethylene (TCE), as it is heated.