Patents


Howard Nathel, Harry E. Cartland, Billy W. Colston, Jr., Matthew J. Everett, and Jeffery N. Roe
Multiple-Wavelength Spectroscopic Quantitation of Light-Absorbing Species in Scattering Media
U.S. Patent 6,015,969
January 18, 2000
An oxygen concentration measurement system for blood hemoglobin comprising a multiple-wavelength, low-coherence optical light source that is coupled by single-mode fibers through a splitter and combiner and focused on both a target tissue sample and a reference mirror. Reflections from both the reference mirror and from the depths of the target tissue sample are carried back and mixed to produce interference fringes in the splitter and combiner. The distance traversed by both reflections is the same. The tissue sample reflections must emanate from a depth sufficient to provide light attenuation information dependent on the oxygen in the tissue's blood hemoglobin. Two wavelengths of light are used to obtain concentrations. The method can be used to measure total hemoglobin concentration or total blood volume in tissue. In conjunction with oxygen saturation measurements from pulse oximetry, it can be used to absolutely quantify oxyhemoglobin in tissue. The apparatus and method provide a general means for absolute quantitation of an absorber dispersed in a highly scattering medium.

Fred Mitlitsky, Blake Myers, and Frank Magnotta
Method for Forming a Bladder for Fluid Storage Vessels
U.S. Patent 6,017,600
January 25, 2000
A lightweight, low-permeability liner for graphite-epoxy compressed-gas storage vessels. The liner is composed of polymers that may or may not be coated with a thin layer of a low-permeability material such as silver, gold, or aluminum. It is deposited on a thin polymeric layer of substrate and formed into a closed bladder using torispherical or near-torispherical endcaps, with or without bosses therein. A high-strength-to-weight material, such as a graphite-epoxy shell, is formed about the torisphere to withstand the storage pressure forces. The polymeric substrate may be laminated on one or both sides with additional layers of polymeric film. The liner may be formed to a desired configuration using a dissolvable mandrel or by inflation techniques, and the edges of the film seamed by heat sealing. The liner may be used in almost any type of gas storage system and is particularly applicable for hydrogen gas mixtures, oxygen used for vehicles, fuel cells or regenerative fuel cell applications, high-altitude solar-powered aircraft, hybrid energy-storage propulsion systems, lunar-Mars space applications, and other applications requiring high cycle life.


Kevin R. Kyle and Steven B. Brown
Cone Penetrometer Fiber-Optic Raman Spectroscopy Probe Assembly
U.S. Patent 6,018,389
January 25, 2000
A chemically and mechanically robust optical Raman spectroscopy probe assembly that can be incorporated in a cone penetrometer (CPT) for subsurface deployment. This assembly consists of an optical Raman probe and a penetrometer-compatible optical probe housing. The probe is intended for in situ chemical analysis of chemical constituents in the surrounding environment. The probe is optically linked by fiber optics to the light source and the detection system at the surface. A built-in broadband light source provides a strobe method for direct measurement of sample optical density. A mechanically stable sapphire window is sealed directly in the sidewall of the housing using a metallic, chemically resistant hermetic seal design. This window permits transmission of the interrogation light beam and the resultant signal. The spectroscopy probe assembly is capable of accepting Raman, laser-induced fluorescence, reflectance, and other optical probes with collimated output for CPT deployment.


Long N. Dinh, Mehdi Balooch, Marcus A. Schildbach, Alex V. Hamza, and William McLean II
Low Work Function, Stable Compound Clusters and Generation Process
U.S. Patent 6,019,913
February 1, 2000
Low-work-function, stable compound clusters are generated by coevaporation of a solid semiconductor (silicon) and alkali metal (cesium) elements in an oxygen environment. The compound clusters are easily patterned during deposition on substrate surfaces using a conventional photoresist technique. The cluster size distribution is narrow, with a peak range of angstroms to nanometers, depending on the oxygen pressure and the silicon source temperature. Tests have shown that when deposited on a carbon substrate, compound clusters contain the desired low-work-function property and are stable up to 600°ree;C. When the plate containing the patterned cluster is used as a cathode baseplate and a faceplate covered with phosphor is used as an anode, a positive bias can be applied to the faceplate to easily extract electrons and obtain illumination.


Peter Celliers, Luiz Da Silva, Michael Glinshy, Richard London, Duncan Maitland, Dennis Matthews, and Pat Fitch
Opto-Acoustic Thrombolysis
U.S. Patent 6,022,309
February 8, 2000
A catheter-based device for generating ultrasound excitation in biological tissue. Pulsed laser light is guided through an optical fiber to provide the energy for producing the acoustic vibrations. The optical energy is deposited in a water-based absorbing fluid (such as saline, a thrombolytic agent, blood, or a thrombus) and generates an acoustic impulse in the fluid through thermoelastic and/or thermodynamic mechanisms. By pulsing the laser at a repetition rate varying from 10 hertz to 100 kilohertz, an ultrasonic radiation field can be established locally in the medium. This method of producing ultrasonic vibrations can be used in vivo for the treatment of stroke-related conditions in humans, particularly for dissolving thrombuses or treating vasospasm. The catheter can also incorporate thrombolytic drug treatments as an adjunct therapy and can be operated with ultrasonic detection equipment for imaging and feedback control and with optical sensors for characterizing thrombus type and consistency.


Joe N. Lucas, Tore Straume, and Kenneth T. Bogen
Detection and Isolation of Nucleic Acid Sequences Using a Bifunctional Hybridization Probe
U.S. Patent 6,027,870
February 22, 2000
A method for detecting and isolating a target sequence in a sample of nucleic acids. It uses a bifunctional probe capable of hybridizing to the target sequence. The probe includes a detectable marker and a complexing agent that can bind with a second complexing agent. A kit that uses this method for detecting a target sequence in a sample of nucleic acids is also provided.


Lawrence J. Cox, Alexis E. Schach Von Wittenau
Evaluated Teletherapy Source Library
U.S. Patent 6,029,079
February 22, 2000
The Evaluated Teletherapy Source Library is a system of hardware and software for maintaining a library of useful phase space descriptions (PSDs) of teletherapy sources used in radiation therapy for cancer treatment. The PSDs are designed to be used by PEREGRINE, the all-particle Monte Carlo dose-calculation system. The library also stores other information such as monitor unit factors for use with the PSDs, results of PEREGRINE calculations using the PSDs, clinical calibration measurements, and geometry descriptions sufficient for calculational purposes. The library can also be a repository for the Monte Carlo simulation history files from which the generic PSDs are derived.


Russell Hudyma
High Numerical Aperture Ring Field Projection System for Extreme Ultraviolet Lithography
U.S. Patent 6,033,079
March 7, 2000
A buffer layer located between a substrate and a multilayer to counteract stress in the multilayer and thus reduce or cancel out substrate deformation. The buffer layer, with a stress of sufficient magnitude and opposite in sign, provides a tunable, near-zero net stress in substrates such as an optic for an extreme ultraviolet lithography tool. Buffer layers have been deposited, for example, between molybdenum-silicon and molybdenum-beryllium multilayer films and their associated substrate, reducing the stress significantly, wherein the magnitude of the stress is less than 100 megapascals and near-normal incidence (5 degrees) reflectance of over 60 percent is obtained at 13.4 and 11.4 nanometers, respectively. The present invention is applicable to crystalline and noncrystalline materials and can be used at ambient temperatures.


Ward Small IV and Peter Celliers
Single-Fiber Multicolor Pyrometry
U.S. Patent 6,012,840
January 11, 2000
An all-reflective optical system for a projection photolithography camera, including a source of extreme ultraviolet radiation, a wafer, and a mask to be imaged on the wafer. The optical system is composed of a first concave mirror, a second mirror, a third convex mirror, a fourth concave mirror, a fifth convex mirror, and a sixth concave mirror. The system is configured so that five of the six mirrors receive a chief ray at an incidence angle less than substantially 12 degrees, and each of the six mirrors receives a chief ray at an incidence angle of less than substantially 15 degrees. Four of the six reflecting surfaces have an aspheric departure of less than substantially 7 micrometers. Five of the six reflecting surfaces have an aspheric departure of less than substantially 14 micrometers. Each of the six reflecting surfaces has an aspheric departure of less than 16 micrometers.


Awards


Becky Failor, a division leader in the Hazards Control Department at Livermore, has received a Distinguished Alumni award from her undergraduate alma mater, Oakland University in Michigan.
Failor currently leads Environment, Safety, and Health Team 3. The Oakland University award cited Failor for her technical and professional accomplishments and for her work with the university over the years, including bringing university students to the Laboratory for summer internships and keeping the university apprised of DOE's surplus equipment list.

The Joint Conflict and Tactical Simulation (JCATS) computer code developed by the Laboratory for combat simulation was honored recently by an award from the Defense Department's Defense Modeling and Simulation Office. Developers Mike Uzelac, Hal Brand, Greg Bowers, and Tom Kelleher traveled to Virginia to receive the award. Faith Shimamoto led the development team, which is part of the Laboratory's Proliferation Detection and Defense Systems Division led by Alan Spero.
First released in 1998, JCATS can simulate large-scale battles and small group operations in rural and urban areas. A second version with increased capabilities was released in October 1999. JCATS development in recent years has been sponsored by the Defense Department's Joint Warfighting Center. Particularly effective in simulating conflicts in urban settings, the code has been used in training exercises such as the Urban Warrior Advanced Warfighting Experiment in the San Francisco Bay Area in March of 1999 and to support actual military operations in places such as Panama, the Persian Gulf, and Bosnia. (See S&TR, January/February 2000, Simulating Warfare Is No Video Game, for details about JCATS's capabilities and deployment.)
JCATS is widely used throughout the government to address a variety of security concerns. Commenting on the effectiveness of the code, Chris Christenson of the Institute for Defense Analysis, a Defense Department contractor for studies and analysis, found "JCATS to be, hands-down, the model of choice for small unit urban operations. Nothing else comes close."

A system that assays containers of radioactive waste safely, accurately, and nonintrusively has garnered a prestigious R&D 100 Award for Lawrence Livermore National Laboratory and its commercial partner, Bio-Imaging Research, Inc.
Developed by a team of engineers and physicists headed by Livermore's Patrick Roberson and Harry Martz, the Waste Inspection Tomography for Non-Destructive Assay (WIT-NDA) system combines computed tomography and gamma-ray spectroscopy to accurately quantify all detectable gamma rays emitted from waste containers. The WIT-NDA is part of the Waste Inspection Tomography system, a product of Bio-Imaging Research (BIR). The BIR system provides nondestructive examination and assay of radioactive waste and has been on the market since August 1999.
"What makes this system unique is that, to use it, we don't need to open the container, we don't need to know what specific waste is inside, and we don't have to calibrate the system to a specific waste," explains Roberson.


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