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Alternating-Polarity Operation for Complete Regeneration of Electrochemical Deionization System
Tri D. Tran, David J. Lenz
U.S. Patent 6,761,809 B2
July 13, 2004
This electrically regenerable battery of electrochemical cells for capacitive deionization (including electrochemical purification) and regeneration of electrodes is operated at alternate polarities during consecutive cycles. Each regeneration step in a deionization–regeneration cycle is operated at a given polarity so that the polarity of the deionization step in the next cycle is maintained. In one configuration, an end electrode is placed at each end of the battery, adjacent to the end plates. An insulator layer is interposed between each end plate and the adjacent end electrode. Each end electrode includes a single sheet of conductive material with a high specific surface area and sorption capacity—preferably a carbon aerogel composite. Between the two end electrodes, several double-sided intermediate electrodes, which are generally identical, are placed equidistant from each other. As the electrolyte enters the battery, it flows through a continuous open serpentine channel that is defined by the electrodes and is substantially parallel to the electrode surfaces. Because the cells are polarized, ions are removed from the electrolyte and are held in the electric double layers formed at the carbon aerogel surfaces of the electrodes. As the electrodes of each cell are saturated with the removed ions, the battery is regenerated electrically at a reversed polarity from that during the deionization step, thus significantly minimizing secondary wastes.

Multi-Stage Separations Based on Dielectrophoresis
Raymond P. Mariella, Jr.
U.S. Patent 6,761,811 B2
July 13, 2004
This separation system uses multistage traps based on dielectrophoresis. Traps with electrodes arranged both transverse and parallel to the flow of particles are used with combinations of direct current and alternating voltage to trap, concentrate, separate, and/or purify target particles.

Method for Optical Pumping of Thin Laser Media at High Average Power
Luis E. Zapata, Raymond J. Beach, Eric C. Honea, Stephen A. Payne
U.S. Patent 6,763,050 B2
July 13, 2004
A thin, planar laser material is bonded to a light guide of an index-matched material forming a composite disk. A diode array or other pump light is introduced into the composite disk through the edges of the disk. Pump light trapped within the composite disk is depleted as it multipasses the laser medium before reaching an opposing edge of the disk. The resulting compound optical structure efficiently delivers concentrated pump light to a laser medium of minimum thickness. A high-performance cooler is attached to the external face of the laser medium to reject heat. Laser beam extraction is parallel to the heat flux so that optical distortions are minimized.

Biologically-Based Signal Processing System Applied to Noise Removal for Signal Extraction
Chi Yung Fu, Loren I. Petrich
U.S. Patent 6,763,339 B2
July 13, 2004
This biologically based signal-processing system improves signal extraction by removing signal noise. A wavelet transform used with a neural network imitates a biological system. The neural network may be trained to remove noise from the signal using either ideal data derived from physical principles or noiseless signals.

Material System for Tailorable White Light Emission and Method for Making Thereof
Christine A. Smith, Howard W. H. Lee
U.S. Patent 6,774,560 B1
August 10, 2004
With this method for processing a composite material, the white-light emission of the resulting composite can be tailored during the excitation phase. The composite material is irradiated with a predetermined power for a specific time to reduce the size of the nanocrystals and the number of traps in the composite material. This irradiation process intensifies the blue light that the nanocrystals contribute to the white-light emission and decreases the red and green light contributed by the traps.

High Gain Preamplifier Based on Optical Parametric Amplification
Igor Jovanovic, Randal A. Bonner
U.S. Patent 6,775,053 B2
August 10, 2004
This high-gain preamplifier is based on optical parametric amplification. A first nonlinear crystal is connected to a second nonlinear crystal. A beam-relay telescope is then connected to a second beam-relay telescope and to the first and second nonlinear crystals. Finally, a harmonic beam splitter is connected to a second harmonic beam splitter, the first and second crystals, and the first and second beam-relay telescopes.

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Lawrence Livermore National Laboratory
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UCRL-52000-04-10 | October 8, 2004