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Generation of low-divergence laser beams

Description: This invention is comprised of an apparatus for transforming a conventional beam of coherent light, having a Gaussian energy distribution and relatively high divergence, into a beam in which the energy distribution approximates a single, non-zero-order Bessel function and which therefore has much lower divergence. The apparatus comprises a zone plate having transmitting and reflecting zones defined by the pattern of light interference produced by the combination of a beam of coherent light with a Gaussian energy distribution and one having such a Bessel distribution. The interference pattern between the two beams is a concentric array of multiple annuli, and is preferably recorded as a hologram. The hologram is then used to form the transmitting, and reflecting zones by photo-etching portions of a reflecting layer deposited on a plate made of a transmitting material. A Bessel beam, containing approximately 50% of the energy of the incident beam, is produced by passing a Gaussian beam through such a Bessel zone plate. The reflected beam, also containing approximately 50% of the incident beam energy and having a Bessel energy distribution, can be redirected in the same direction and parallel to the transmitted beam. Alternatively, a filter similar to the Bessel zone plate can be placed within the resonator cavity of a conventional laser system having a front mirror and a rear mirror, preferably axially aligned with the mirrors and just inside the front mirror to generate Bessel energy distribution light beams at the laser source.
Date: December 1992
Creator: Kronberg, J. W.
Partner: UNT Libraries Government Documents Department

Audible radiation monitor

Description: This invention consists of a method and apparatus for monitoring ionizing radiation comprising radiation detectors in electrical connection with an isotopic analyzer and a device for producing chords to which each isotope is mapped so that the device produces a unique chord for each isotope. Preferably the chords are pleasing to the ear, except for chords representing unexpected isotopes, and are louder or softer depending on the level of radioactivity produced by each isotope, and musical instrument voices may be simulated in producing the chords as an aid to distinguishing similar-sounding chords. Because of the representation by chords, information regarding the level and composition of the radiation in an area can be conveyed to workers in that area more effectively and yet without distracting them.
Date: December 31, 1992
Creator: Odell, D.M.C.
Partner: UNT Libraries Government Documents Department

A coal-water slurry fueled internal combustion engine and method for operating same

Description: An internal combustion engine fueled with a coal-water slurry is described. About 90 percent of the coal-water slurry charge utilized in the power cycle of the engine is directly injected into the main combustion chamber where it is ignited by a hot stream of combustion gases discharged from a pilot combustion chamber of a size less than about 10 percent of the total clearance volume of main combustion chamber with the piston at top dead center. The stream of hot combustion gases is provided by injecting less than about 10 percent of the total coal-water slurry charge into the pilot combustion chamber and using a portion of the air from the main combustion chamber that has been heated by the walls defining the pilot combustion chamber as the ignition source for the coal-water slurry injected into the pilot combustion chamber.
Date: December 31, 1992
Creator: McMillian, M.H.
Partner: UNT Libraries Government Documents Department

Ventilation of porous media

Description: Methods for distributing gases throughout the interstices of porous materials and removing volatile substances from the interstices of porous materials. Continuous oscillation of pressures and flows results in increased penetration of the interstices by flowing gases and increased transport of gaseous components out of the interstices. The invention is particularly useful in soil vapor extraction.
Date: December 31, 1992
Creator: Neeper, D.A.
Partner: UNT Libraries Government Documents Department

Glass melter off-gas system

Description: This invention is comprised of an apparatus and method for melting glass in a glass melter in such a way as to reduce deposition of particulates in the off-gas duct. Deposit accumulation is reduced by achieving an off-gas velocity above approximately 15 meters/second and an off-gas temperature as close as possible to, but not higher than, the glass softening point. Because the deposits are largely water-soluble, those that do form on the interior surface of the duct can be readily removed by injecting water or steam directly into the off-gas duct from its entrance or exit.
Date: December 31, 1992
Creator: Jantzen, C.M.
Partner: UNT Libraries Government Documents Department

Vacuum tool manipulator

Description: This invention is comprised of an apparatus for manipulating a vacuum hose in a reactor vessel comprising a housing with two opposing openings, an arm carried by the housing and deployable from a stowed position essentially completely within the housing to an extended position where the arm extends through the two openings in a generally horizontal position. The arm preferably has a two-fingered gripping device for gripping the vacuum hose but may carry a different end effector such as a grinding wheel. The fingers are opened and closed by one air cylinder. A second air cylinder extends the device. A third air cylinder within the housing pivotally pulls the opposing end of the arm into the housing via a pivoting member pivotally connected between the third air cylinder shaft and the arm.
Date: December 31, 1992
Creator: Zollinger, W.T.
Partner: UNT Libraries Government Documents Department

Ultrasonic fluid flow measurement method and apparatus

Description: This invention is comprised of an apparatus for measuring the flow of a fluid in a pipe using ultrasonic waves. The apparatus comprises an ultrasonic generator, a lens for focusing the sound energy produced by the generator, and means for directing the focused energy into the side of the pipe through an opening and in a direction close to parallel to the long axis of the pipe. A cone carries the sound energy to the lens from the generator. Depending on the choice of materials, there may be a quarter-wave, acoustic impedance matching section between the generator and the cone to reduce the reflections of energy at the cone boundary. The lens material has an acoustic impedance similar to that of the cone material but a different sonic velocity so that the lens can converge the sound waves in the fluid. A transition section between the lens and the fluid helps to couple the energy to the fluid and assures it is directed as close to parallel to the fluid flow direction as possible.
Date: December 31, 1992
Creator: Kronberg, J.W.
Partner: UNT Libraries Government Documents Department

Three dimensional, multi-chip module

Description: The present invention relates to integrated circuit packaging technology, and particularly to three dimensional packages involving high density stacks of integrated circuits. A plurality of multi-chip modules are stacked and bonded around the perimeter by sold-bump bonds to adjacent modules on, for instance, three sides of the perimeter. The fourth side can be used for coolant distribution, for more interconnect structures, or other features, depending on particular design considerations of the chip set. The multi-chip modules comprise a circuit board, having a planarized interconnect structure formed on a first major surface, and integrated circuit chips bonded to the planarized interconnect surface. Around the periphery of each circuit board, long, narrow ``dummy chips`` are bonded to the finished circuit board to form a perimeter wall. The wall is higher than any of the chips on the circuit board, so that the flat back surface of the board above will only touch the perimeter wall. Module-to-module interconnect is laser-patterned on the sides of the boards and over the perimeter wall in the same way and at the same time that chip to board interconnect may be laser-patterned.
Date: December 31, 1992
Creator: Bernhardt, A.F. & Petersen, R.W.
Partner: UNT Libraries Government Documents Department

Reactor refueling containment system

Description: This report describes a method of refueling a nuclear reactor whereby the drive mechanism is disengaged and removed by activating a jacking mechanism that raises the closure head. The area between the barrier plate and closure head is exhausted through the closure head penetrations. The closure head, upper drive mechanism, and bellows seal are lifted away and transported to a safe area. The barrier plate acts as the primary boundary and each drive and control rod penetration has an elastomer seal preventing excessive tritium gases from escaping. The individual instrumentation plugs are disengaged allowing the corresponding fuel assembly to be sealed and replaced.
Date: December 31, 1992
Creator: Gillett, J.E. & Meuschke, R.E.
Partner: UNT Libraries Government Documents Department

Underwater manipulator

Description: This invention is comprised of a self-contained, waterproof, water-submersible, remote-controlled apparatus provided for manipulating a device, such as an ultrasonic transducer for measuring crack propagation on an underwater specimen undergoing shock testing. The subject manipulator includes metal bellows for transmittal of angular motions without the use of rotating shaft seals or O-rings. Inside the manipulator, a first stepper motor controls angular movement. In the preferred embodiment, the bellows permit the first stepper motor to move an ultrasonic transducer {plus_minus} 45 degrees in a first plane and a second bellows permit a second stepper motor to move the transducer {plus_minus} 10 degrees in a second plane orthogonal to the first. In addition, an XY motor-driven table provides XY motion.
Date: December 31, 1992
Creator: Schrum, P.B. & Cohen, G.H.
Partner: UNT Libraries Government Documents Department

Superconducting thermoelectric generator

Description: This invention is comprised of an apparatus and method for producing electricity from heat. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a higher thermal conductivity than that of the superconducting material. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials, establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device.
Date: December 31, 1992
Creator: Metzger, J.D. & El-Genk, M.
Partner: UNT Libraries Government Documents Department

Method and apparatus for providing pulse pile-up correction in charge quantizing radiation detection systems

Description: This invention is comprised of a radiation detection method and system for continuously correcting the quantization of detected charge during pulse pile-up conditions. Charge pulses from a radiation detector responsive to the energy of detected radiation events are converted to voltage pulses of predetermined shape whose peak amplitudes are proportional to the quantity of charge of each corresponding detected event by means of a charge-sensitive preamplifier. These peak amplitudes are sampled and stored sequentially in accordance with their respective times of occurrence. Based on the stored peak amplitudes and times of occurrence, a correction factor is generated which represents the fraction of a previous pulses influence on a preceding pulse peak amplitude. This correction factor is subtracted from the following pulse amplitude in a summing amplifier whose output then represents the corrected charge quantity measurement.
Date: December 31, 1992
Creator: Britton, C.L. Jr. & Wintenberg, A.L.
Partner: UNT Libraries Government Documents Department

Crack detection using resonant ultrasound spectroscopy

Description: This invention is comprised of a method and apparatus for detecting crack-like flaws in components. A plurality of exciting frequencies are generated and applied to a component in a dry condition to obtain a first ultrasonic spectrum of the component. The component is then wet with a selected liquid to penetrate any crack-like flaws in the component. The plurality of exciting frequencies are again applied to the component and a second ultrasonic spectrum of the component is obtained. The wet and dry ultrasonic spectra are then analyzed to determine the second harmonic components in each of the ultrasonic resonance spectra and the second harmonic components are compared to ascertain the presence of crack-like flaws in the component.
Date: December 31, 1992
Creator: Migliori, A. & Bell, T.M.
Partner: UNT Libraries Government Documents Department

Fast-acting nuclear reactor control device

Description: This invention consists of a fast-acting nuclear reactor control device for moving and positioning a safety control rod to desired elevations within the core of the reactor between a run position in which the safety control rod is outside the reactor core, and a shutdown position in which the rod is fully inserted in the reactor core. The device employs a hydraulic pump motor, an electric gear motor, and a solenoid valve to drive the safety control rod into the reactor core through the entire stroke of the safety control rod. An overrunning clutch, allows the safety control rod to freely travel toward a safe position in the event of a partial drive system failure.
Date: December 31, 1992
Creator: Kotlyar, O.M. & West, P.B.
Partner: UNT Libraries Government Documents Department

DNA fragment sizing and sorting by laser-induced fluorescence

Description: A method is provided for obtaining DNA fingerprints using high speed detection systems, such as flow cytometry to determine unique characteristics of DNA pieces from a selected sample. In one characterization the DNA piece is fragmented at preselected sites to produce a plurality of DNA fragments. The DNA piece or the resulting DNA fragments are treated with a dye effective to stain stoichiometrically the DNA fragments. The fluorescence from the dye in the stained fragments is then examined to generate an output functionally related to the number of nucleotides in each one of the DNA fragments. In one embodiment, the intensity of the fluorescence emissions from each fragment is directly proportional to the fragment length. Additional dyes can be bound to the DNA piece and DNA fragments to provide information additional to length information. Oligonucleotide specific dyes and/or hybridization probes can be bound to the DNA fragments to provide information on oligonucleotide distribution or probe hybridization to DNA fragments of different sizes.
Date: December 31, 1992
Creator: Jett, J.H.; Hammond, M.L.; Keller, R.A.; Marrone, B.L. & Martin, J.C.
Partner: UNT Libraries Government Documents Department

A gas stream clean-up filter and method for forming same

Description: A gas cleaning filter is formed in-situ within a vessel containing a fluidizable bed of granular material of a relatively large size fraction. A filter membrane provided by a porous metal or ceramic body or such a body supported a perforated screen on one side thereof is coated in-situ with a layer of the granular material from the fluidized bed by serially passing a bed-fluidizing gas stream through the bed of granular material and the membrane. The layer of granular material provides the filtering medium for the combined membrane-granular layer filter. The filter is not blinded by the granular material and provides for the removal of virtually all of the particulates from a process gas stream. The granular material can be at least partially provided by a material capable of chemically reacting with and removing sulfur compounds from the process gas stream. Low level radioactive waste containing organic material may be incinerated in a fluidized bed in communication with the described filter for removing particulates from the gaseous combustion products.
Date: December 1992
Creator: Mei, J. S.; Halow, J. S. & DeVault, J. D.
Partner: UNT Libraries Government Documents Department

Anisotropic fiber alignment in composite structures

Description: High strength material composite structures are formed with oriented fibers to provide controlled anisotropic fibers. Fibers suspended in non-dilute concentrations (e.g., up to 20 volume percent for fibers having an aspect ratio of 20) in a selected medium are oriented by moving an axially spaced array of elements in the direction of desired fiber alignment. The array elements are generally perpendicular to the desired orientation. The suspension medium may also include sphere-like particles where the resulting material is a ceramic.
Date: December 31, 1992
Creator: Graham, A.L.; Mondy, L.A. & Guell, D.C.
Partner: UNT Libraries Government Documents Department

Expert system for online surveillance of nuclear reactor coolant pumps

Description: This report describes an expert system for online surveillance of nuclear reactor coolant pumps. This system provides a means for early detection of pump or sensor degradation. Degradation is determined through the use of a statistical analysis technique, sequential probability ratio test, applied to information from several sensors which are responsive to differing physical parameters. The results of sequential testing of the data provide the operator with an early warning of possible sensor or pump failure.
Date: December 31, 1992
Creator: Gross, K.C.; Singer, R.M. & Humenik, K.E.
Partner: UNT Libraries Government Documents Department

Method of and system for producing electrical power

Description: A method and system for converting the chemical energy of methane to electrical energy. Methane is thermally decomposed to hydrogen and carbon in a decomposing unit at a temperature not less than about 1200{degree}K and at a pressure at least slightly above atmospheric pressure. Carbon and substantially pure oxygen and a cesium or potassium seed material is transmitted to a combustor which is maintained at a pressure of at least about 50 atmospheres to combust the carbon and oxygen and provide an ionized plasma having a temperature not less than about 2900{degree}K. The ionized plasma is accelerated to a velocity not less than about 1000 m/sec and transported through an MHD generator having a magnetic field in the range of from about 4 to about 6 Tesla to generate dc power. The ionized plasma is deaccelerated and passed from the MHD generator in heat exchange relationship with the methane to heat same for decomposition, and thereafter any cesium or potassium seed material is recovered and transported to the combustor, and the dc power from the MHD generator is converted to ac power.
Date: December 31, 1992
Creator: Carabetta, R.A.; Staats, G.E. & Cutting, J.C.
Partner: UNT Libraries Government Documents Department

Organic or organometallic template mediated clay synthesis

Description: A method is given for incorporating diverse varieties of intercalants or templates directly during hydrothermal synthesis of clays such as hectorite or montmorillonite-type layer-silicate clays. For a hectorite layer-silicate clay, refluxing a gel of silica sol, magnesium hydroxide sol and LiF for 2 days with an organic or organometallic intercalant or template results in crystalline products containing either (a) organic dye molecules such as ethyl violet and methyl green, (b) dye molecules such as alcian blue based on a Cu(II)-phthalocyannine complex, or (c) transition metal complexes such as Ru(II)phenanthroline and Co(III)sepulchrate or (d) water-soluble porphyrins and metalloporphyrins. Montmorillonite-type clays are made by the method taught by US patent No. 3,887,454 issued to Hickson, June 13, 1975; however, a variety of intercalants or templates may be introduced. The intercalants or templates should have water-solubility, positive charge, and thermal stability under moderately basic (pH 9-10) aqueous reflux conditions or hydrothermal pressurized conditions for the montmorillonite-type clays.
Date: December 31, 1992
Creator: Gregar, K.C.; Winans, R.E. & Botto, R.E.
Partner: UNT Libraries Government Documents Department

Superconducting active impedance converter

Description: This invention is comprised of a transimpedance amplifier for use with high temperature superconducting, other superconducting, and conventional semiconductor allows for appropriate signal amplification and impedance matching to processing electronics. The amplifier incorporates the superconducting flux flow transistor into a differential amplifier configuration which allows for operation over a wide temperature range, and is characterized by high gain, relatively low noise, and response times less than 200 picoseconds over at least a 10--80 K temperature range. The invention is particularly useful when a signal derived from either far-IR focal plane detectors or from Josephson junctions is to be processed by higher signal/higher impedance electronics, such as conventional semiconductor technology.
Date: December 31, 1992
Creator: Ginley, D.S.; Hietala, V.M. & Martens, J.S.
Partner: UNT Libraries Government Documents Department

Laser focus compensating sensing and imaging device

Description: A laser focus compensating sensing and imaging device permits the focus of a single focal point of different frequency laser beams emanating from the same source point. In particular it allows the focusing of laser beams originating from the same laser device but having differing intensities so that a low intensity beam will not convert to a higher frequency when passing through a conversion crystal associated with the laser generating device. The laser focus compensating sensing and imaging device uses a cassegrain system to fold the lower frequency, low intensity beam back upon itself so that it will focus at the same focal point as a high intensity beam. An angular tilt compensating lens is mounted about the secondary mirror of the cassegrain system to assist in alignment. In addition cameras or CCD`s are mounted with the primary mirror to sense the focused image. A convex lens in positioned coaxial with the cassegrain system on the side of the primary mirror distal of the secondary for use in aligning a target with the laser beam. A first alternate embodiment includes a cassegrain system using a series of shuttles and an internally mounted dichroic mirror. A second alternate embodiment uses two laser focus compensating sensing and imaging devices for aligning a moving tool with a work piece.
Date: December 31, 1992
Creator: Vann, C.S.
Partner: UNT Libraries Government Documents Department

Method for dissolving delta-phase plutonium

Description: A process for dissolving plutonium, and in particular, delta-phase plutonium. The process includes heating a mixture of nitric acid, hydroxylammonium nitrate and potassium fluoride (HAN) to a temperature between 40 and 70 C, then immersing the metal in the mixture. Preferably, the nitric acid has a concentration of not ore than 2M, the HAN approximately 0.66M, and the potassium fluoride 1M. Additionally, a small amount of sulfamic acid, such as 0.1M can be added to assure stability of the HAN in the presence of nitric acid. The oxide layer that forms on plutonium metal may be removed with a non-oxidizing acid as a pre-treatment step.
Date: December 31, 1992
Creator: Karraker, D.G.
Partner: UNT Libraries Government Documents Department

Nozzle mixing apparatus

Description: This invention is comprised of a nozzle device for causing two fluids to mix together. In particular, a spray nozzle comprise two hollow, concentric housings, an inner housing and an outer housing. The inner housing has a channel formed therethrough for a first fluid. Its outer surface cooperates with the interior surface of the outer housing to define the second channel for a second fluid. The outer surface of the inner housing and the inner surface of the outer housing each carry a plurality of vanes that interleave but do not touch, each vane of one housing being between two vanes of the other housing. The vanes are curved and the inner surface of the outer housing and the outer surface of the inner housing converge to narrow the second channel. The shape of second channel results in a swirling, accelerating second fluid that will impact the first fluid just past the end of the nozzle where mixing will take place.
Date: December 31, 1992
Creator: Mensink, D.L.
Partner: UNT Libraries Government Documents Department