M. Leslie Carman and Robert T. Taylor
Method for Enhanced Longevity of In Situ Microbial Filter Used for Bioremediation
U.S. Patent 5,888,395
March 30, 1999
An improved method for in situ microbial filter bioremediation based on placing an in situ microbial filter with increased operating life. A method for generating a microbial filter of sufficient catalytic density and thickness to increase replenishment interval, improve bacteria attachment and detachment characteristics, and provide endogenous stability under in situ conditions. A system for in situ water remediation.

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.


A Laboratory team that developed a system for treating cerebral aneurysms faster and less invasively has received a Federal Laboratory Consortium Award for Excellence in Technology Transfer. Team members include Abraham Lee, Duncan Maitland, Luiz Da Silva, Dean Hadley, Christopher Lee, Pat Fitch, Dan Schumann, and Jim Sommercorn.
The annual award recognizes laboratory employees who have accomplished outstanding work in the process of transferring a federal lab-developed technology to the commercial marketplace. This year, the Livermore team was one of 15 recipients nationwide.
The team's technology uses a laser-activated microgripper to release a coil inside cerebral aneurysms in less than a second. The coil seals off the aneurysm, greatly reducing the patient's risk of acute hemorraghic stroke. Duncan Maitland, group leader within the Defense and Nuclear Technologies, Engineering, and Laser Programs directorates' Medical Technology Program, said that the dramatically quick release of the coil has the potential to reduce patient health risks and lower operation costs.

Nuclear chemist Darleane Hoffman will receive the Priestley Medal, the American Chemical Society's (ACS's) highest honor, at the society's next national meeting in San Francisco in March 2000. Hoffman, chemistry professor in the graduate school of the University of California at Berkeley, helped found the Glenn T. Seaborg Institute for Transactinium Science at Lawrence Livermore and served as its first director from 1991 to 1996. The institute researches the atomic composition of synthesized elements that are heavier than uranium. Hoffman still plays an active role there as mentor, researcher, and teacher.
Only the second woman to receive the medal, Hoffman is being recognized for her work in the chemical properties of heavy elements. Among her accomplishments are the discovery of plutonium-244 in nature and the first investigations of the chemistry of element 106, seaborgium. Her many honors include the 1990 Garvan Medal, which was awarded by ACS to honor distinguished service to chemistry by women chemists, and the National Medal of Science in 1997. She was elected to the Norwegian Academy of Sciences and Letters in 1991 and the American Academy of Arts and Sciences in 1998.

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