Patents


David M. Sanders and Derek E. Decker
Method and Apparatus for Fabrication of High-Gradient Insulators with Parallel Surface Conductors Spaced Less Than One Millimeter Apart
U.S. Patent 5,955,221
September 21, 1999
A process using optical patterns and lithographic techniques to embed parallel and evenly spaced conductors in the nonplanar surfaces of an insulator to produce high-gradient insulators. The approach increases the size to which high-gradient insulating structures can be fabricated and improves the performance of those insulators by reducing the scale of the parallel, alternating insulator/conductor lines on the insulator's surface. This fabrication approach also substantially decreases the cost of producing high-gradient insulators.

Paul R. Coronado and John F. Poco
Flexible Aerogel Composite for Mechanical Stability and Process of Fabrication
U.S. Patent 5,973,015
October 26, 1999
A flexible aerogel and process of fabrication. An aerogel solution is mixed with fibers in a mold and allowed to gel. The gel is then processed by supercritical extraction or air drying to produce a flexible aerogel formed to the shape of the mold. The flexible aerogel has excellent thermal and acoustic properties and can be used in numerous applications, such as for energy absorption and for temperature and acoustic insulation, especially in the contours of aircraft and where space is limited. The flexible aerogel may be of an inorganic (silica) or organic (carbon) type, containing fibers of same.


Jordin T. Kare
Method and Apparatus for Reducing Range Ambiguity in Synthetic Aperture Radar
U.S. Patent 5,973,634
October 26, 1999
A modified synthetic aperture radar system with reduced sensitivity to range ambiguities. It uses secondary receiver channels to detect the range-ambiguous signals and subtract them from the signal received by the main channel. Both desired and range-ambiguous signals are detected by a main receiver and by one or more identical secondary receivers. All receivers are connected to a common antenna with two or more feed systems offset in elevation. The output of the secondary receiver(s) is then subtracted from the main receiver output in such a way as to cancel the ambiguous signals while only slightly attenuating the desired signal and slightly increasing the noise in the main channel. Thus, output of secondary receiver(s) does not significantly affect the desired signal. The subtraction may be done in real time, or outputs of the receivers may be recorded separately and combined during signal processing.


Charles R. Carrigan and John J. Nitao
Electro-Osmotic Infusion for Joule Heating Soil Remediation Techniques
U.S. Patent 5,975,799
November 2, 1999
A method of using electro-osmotic infusion of groundwater or chemically tailored electrolyte to enhance, maintain, or recondition electrical conductivity during joule-heating remediation. Induced flows can be used to infuse electrolyte with enhanced ionic conductivity into the vicinity of the electrodes, maintain the local saturation of near-electrode regions, and resaturate a partially dried-out zone with groundwater. Electro-osmotic infusion can also tailor the conductivity throughout the target layer by infusing chemically modified or heated electrolyte to improve conductivity contrast of the interior. Periodic polarity reversals will prevent large pH changes at the electrodes. This infusion method can be used to condition the electrical conductivity of the soil, particularly low-permeability soil, before and during the heating operation. Electro-osmotic infusion is carried out by locating one or more electrodes adjacent to the heating electrodes and applying a dc potential between two or more electrodes. Depending on the polarities of the electrodes, the induced flow will be toward the heating electrodes or away from them. In addition, electrodes carrying a dc potential may be located throughout the target area to tailor its conductivity.


James C. Davidson and Joseph W. Balch
Microinjector Sample Delivery System for Charged Molecules
U.S. Patent 5,980,713
November 9, 1999
A microinjector sample delivery system for charged molecules. The injector is used for collecting and delivering controlled amounts of charged molecule samples for subsequent analysis. The injector delivery system can be scaled to large numbers (greater than 96) for sample delivery to massively parallel high-throughput analysis systems. The essence of the injector system is an electric-field-controllable loading tip that includes a section of porous material. By applying the appropriate polarity bias potential to the injector tip, charged molecules will migrate into porous material, and by reversing the polarity bias potential, the molecules are ejected or forced away from the tip. The invention has application for uptake of charged biological molecules (for example, proteins, nucleic acids, polymers, for delivery to analytical systems and for use in automated sample delivery systems.


Richard A. Van Konynenburg and Joseph C. Farmer
Means for Limiting and Ameliorating Electrode Shorting
U.S. Patent 5,980,718
November 9, 1999
A fuse and filter arrangement for limiting and ameliorating electrode shorting in capacitive deionization water purification systems that use, for example, carbon aerogel. This arrangement limits and ameliorates the effects of conducting particles or debonded carbon aerogel in shorting the electrodes of a system such as a capacitive deionization water purification system. This limiting and amelioration are important because of the small interelectrode spacing and the finite possibility of debonding or fragmentation of carbon aerogel in a large system. The fuse and filter arrangement electrically protects the entire system from shutting down if a single pair of electrodes is shorted and mechanically prevents a conduction particle from migrating through the electrode stack and shorting the series of electrode pairs in sequence. It also limits the amount of energy released in a shorting event. The arrangement consists of a set of circuit breakers or fuses with one fuse or breaker in the power line connected to one electrode of each electrode pair as well as a set of screens or filters in the water flow channels between each set of electrode pairs.


Brian D. Andresen and Fred S. Miller
Ultratrace Detector for Hand-Held Gas Chromatography
U.S. Patent 5,980,832
November 9, 1999
An ultratrace detector system for handheld chromatography. The system has high sensitivity to emissions generated during production of weapons, biological compounds, and drugs. The system is insensitive to water, air, helium, argon, oxygen, and carbon dioxide. It is composed of a handheld capillary gas chromatograph (GC), an insulated heated redox chamber, a detection chamber, and a vapor trap. The system may, for example, use gas-phase redox reactions and spectral absorption of mercury vapor. The GC initially separates compounds that percolate through a bed of heated mercuric oxide (HgO) in a silica (or other metal) aerogel, which acts as an insulator. Compounds easily oxidized by HgO liberate atomic mercury, which subsequently passes through a detection chamber. This chamber includes a detector cell (such as quartz) illuminated with a 254-nanometer ultraviolet mercury discharge lamp that generates the exact mercury absorption bands used to detect the liberated mercury atoms. Atomic mercury, which strongly absorbs 254-nanometer energy, is therefore a specific signal for reducing compounds eluting from the capillary GC, whereafter it is trapped in, for example, a silicon-aerogel trap.



Awards


Laboratory scientists Anne Happel, Christine Hartmann Siantar, Bill Nellis, and Mordy Rosen were recently honored with the first-ever Edward Teller Fellowship awards. The Director's Office initiated the Teller fellowships to honor one of the Laboratory's most distinguished founders. The fellowships recognize and promote the scientific accomplishments of recipients, all of whom have made pioneering advances in their fields of expertise. They also provide fellows with the flexibility to expand their research or explore new areas of scientific inquiry..
Anne Happel of the Laboratory's Environmental Restoration Division was honored for her outstanding scientific accomplishments in studying environmental contaminants, particularly methyl tertiary-butyl ether (MTBE), in California's groundwater. Her widely recognized research has examined the extent of MTBE contamination in the state's groundwater and the behavior of the compound at leaking underground-fuel-tank sites. Currently, she is developing a Geographical Information System for California that will be used to assess the threat posed by MTBE leaking from tanks to groundwater resources.
With the fellowship, she plans to expand her analysis to other areas of the United States as well as continue to serve on federal Environmental Protection Agency policy panels.
Christine Hartmann Siantar, principal investigator for the PEREGRINE radiation dose calculation program in the Physics Directorate, was honored for her "unique and exemplary record of important scientific discoveries and leadership in the PEREGRINE Program." Her previous honors include an R&D 100 Award in 1999, the Department of Energy's Young Independent Scientist Award in 1996, and the Presidential Early Career Award for Scientists and Engineers in 1996.
With her Edward Teller Fellowship, she intends to study how radiation damages DNA.
Bill Nellis, who codiscovered a method for achieving metallized fluid hydrogen, was recognized for his excellent, long-standing contributions to and influence on the field of shock physics. Most noteworthy, according to his award, are his "innovative research efforts in the use of impact-generated shocks to measure the properties of dense, warm molecular and atomic fluids." He is a fellow of the American Physical Society, has published 166 papers, and holds five patents. All of his work at the Laboratory has involved shock compression of solids, liquids, and aerogels.
The award enabled him to work as a visiting fellow at Trinity College, Oxford University, from mid-February through mid-March 2000. He also plans to start a book on fluids at high pressures and temperatures.
Mordy Rosen, a former division leader in the Defense and Nuclear Technologies Directorate and now the division's chief scientist, was cited for his "long-standing scientific excellence not only at LLNL for over 20 years, but also for [his] contributions at UC Berkeley and UC Davis." His honors and awards include being a centennial lecturer of the American Physical Society in 1999, an American Physical Society fellow, and one of the top 100 innovators named by Science Digest in 1985 for his work on x-ray lasers. He has cowritten nearly 300 publications.
Rosen intends to use his fellowship to enhance the science base of DOE's Stockpile Stewardship Program. In particular, he plans to study radiation transport in complex geometries and present a more technically rigorous case than those previously made for the use of aboveground experimental facilities such as the National Ignition Facility. In addition, Rosen plans to develop and teach a course in high-energy-density physics.

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