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Integrated null-flux suspension and multiphase propulsion system for magnetically-levitated vehicles (open access)

Integrated null-flux suspension and multiphase propulsion system for magnetically-levitated vehicles

This report discusses a propulsion and stabilization system comprising a series of figure 8 coils mounted vertically on the walls of the guideway to provide suspension, lateral guidance and propulsion of a magnetically levitated vehicle. This system further allows for altering the magnetic field effects by changing the relative position of the loops comprising the figure 8 coils either longitudinally and/or vertically with resulting changes in the propulsion, the vertical stability, and the suspension.
Date: January 1, 1992
Creator: Rote, D. M.; He, Jianliang & Johnson, L. R.
System: The UNT Digital Library
Method to synthesize dense crystallized sodalite pellet for immobilizing halide salt radioactive waste (open access)

Method to synthesize dense crystallized sodalite pellet for immobilizing halide salt radioactive waste

This report describes a method for immobilizing waste chloride salts containing radionuclides such as cesium and strontium and hazardous materials such as barium. A sodalite intermediate is prepared by mixing appropriate amounts of silica, alumina and sodium hydroxide with respect to sodalite and heating the mixture to form the sodalite intermediate and water. Heating is continued to drive off the water to form a water-free intermediate. The water-free intermediate is mixed with either waste salt or waste salt which has been contacted with zeolite to concentrate the radionuclides and hazardous material. The waste salt-intermediate mixture is then compacted and heated under conditions of heat and pressure to form sodalite with the waste salt, radionuclides and hazardous material trapped within the sodalite cage structure. This provides a final product having excellent leach resistant capabilities.
Date: January 1, 1992
Creator: Koyama, T.
System: The UNT Digital Library
Improved high speed maglev design (open access)

Improved high speed maglev design

This report discusses a propulsion and stabilization system for an inductive repulsion type magnetically levitated vehicle which is propelled and suspended by a system which includes dividing the superconducting magnets into two types: a strong field magnet which is located vertically below the vehicle for propulsion and guidance and a weak field superconducting magnet located at the ends of the vehicle for levitation and added guidance. Several proposed embodiments exist for the placement of the magnetic field shielding: locating the shielding on the vehicle, locating the shielding on the guideway, and locating the shielding on the guideway and adding shielding to the vertical undercarriage. In addition, the separation between the be vehicle and the guideway can be controlled to reduce the exposure of the passenger cabin to magnetic fields.
Date: January 1, 1992
Creator: Rote, D. M.; He, Jianliang & Coffey, H. T.
System: The UNT Digital Library
Method for exponentiating in cryptographic systems (open access)

Method for exponentiating in cryptographic systems

An improved cryptographic method utilizing exponentiation is provided which has the advantage of reducing the number of multiplications required to determine the legitimacy of a message or user. The basic method comprises the steps of selecting a key from a pre-approved group of integer keys g; exponentiating the key by an integer value e, where e represents a digital signature, to generate a value g{sup e}; transmitting the value g{sup e} to a remote facility by a communications network; receiving the value g{sup e} at the remote facility; and verifying the digital signature as originating from the legitimate user. The exponentiating step comprises the steps of initializing a plurality of memory locations with a plurality of values g{sup xi}, computing a{sub i} representations for a integer base b, where a{sub i} represents the weighing factor of the ith digit of the integer e; computing the individual values of c{sub d} according to the rule: c{sub d}={product}a{sub i}=d g{sup x {sub i}}; and computing the product of {product}{sup h}/{sub d=1} c{sub d}{sup d} from the stored values of from the plurality of memory locations so as to determine a value for g{sup e}.
Date: December 31, 1992
Creator: Brickell, E. F.; Gordon, D. M. & McCurley, K. S.
System: The UNT Digital Library
Filtered cathodic arc source (open access)

Filtered cathodic arc source

Disclosed is a continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45{degrees} to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles.
Date: December 31, 1992
Creator: Falabella, S. & Sanders, D. M.
System: The UNT Digital Library
Method and apparatus for determining two-phase flow in rock fracture (open access)

Method and apparatus for determining two-phase flow in rock fracture

One object of the present invention to provide an improved method and apparatus for measuring the relative permeability of a rock fracture to multiple phases in a manner which will provide even more uniform delivery of both wetting and non-wetting phases to the fracture edge. It is another object of the invention to provide an improved method and apparatus for measuring the permeability of multiple phases through a rock fracture which comprises delivering the respective phases through manifold means to uniformly deliver the respective phases to and from opposite edges of the rock fracture in a distributed manner across the gap of the fracture wherein the manifold means for delivering the wetting phase comprises porous block means having a side facing the rock fracture edge and bore means therein for providing uniform distribution of the wetting phase to the porous block surfaces, and the manifold means for delivering the non-wetting phase include a plenum in communication with parallel grooves disposed on a surface of the porous means facing perpendicular to the rock fracture edge. These and other objects of the invention will be apparent from the following description and accompanying drawings.
Date: December 31, 1992
Creator: Persoff, P.; Pruess, K. & Myer, L.
System: The UNT Digital Library
Traveling-wave photodetector (open access)

Traveling-wave photodetector

The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size.
Date: December 31, 1992
Creator: Hietala, V. M. & Vawter, G. A.
System: The UNT Digital Library
Phase-sensitive flow cytometer (open access)

Phase-sensitive flow cytometer

This report describes phase-sensitive flow cytometer (FCM) which provides additional FCM capability to use the fluorescence lifetime of one or more fluorochromes bound to single cells to provide additional information regarding the cells. The resulting fluorescence emission can be resolved into individual fluorescence signals if two fluorochromes are present or can be converted directly to a decay lifetime from a single fluorochrome. The excitation light for the fluorochromes is modulated to produce an amplitude modulated fluorescence pulse as the fluorochrome is excited in the FCM. The modulation signal also forms a reference signal that is phase-shifted a selected amount for subsequent mixing with the output modulated fluorescence intensity signal in phase-sensitive detection circuitry. The output from the phase-sensitive circuitry is then an individual resolved fluorochrome signal or a single fluorochrome decay lifetime, depending on the applied phase shifts.
Date: December 31, 1992
Creator: Steinkamp, J. A.
System: The UNT Digital Library
Enhanced radiation resistant fiber optics (open access)

Enhanced radiation resistant fiber optics

A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.
Date: December 31, 1992
Creator: Lyons, P. B. & Looney, L. D.
System: The UNT Digital Library
Sensors for Monitoring Waste Glass Quality (open access)

Sensors for Monitoring Waste Glass Quality

None
Date: December 31, 1992
Creator: Bickford, Dennis F.
System: The UNT Digital Library
High brightness electron accelerator (open access)

High brightness electron accelerator

A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of acclerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity.
Date: December 31, 1992
Creator: Sheffield, R. L.; Carlsten, B. E. & Young, L. M.
System: The UNT Digital Library
Apparatus for preparing a sample for mass spectrometry (open access)

Apparatus for preparing a sample for mass spectrometry

Disclosed is an apparatus for preparing a sample for analysis by a mass spectrometer system. The apparatus has an entry chamber and an ionization chamber separated by a skimmer. A capacitor having two space-apart electrodes followed by one or more ion-imaging lenses is disposed in the ionization chamber. The chamber is evacuated and the capacitor is charged. A valve injects a sample gas in the form of sample pulses into the entry chamber. The pulse is collimated by the skimmer and enters the ionization chamber. When the sample pulse passes through the gap between the electrodes, it discharges the capacitor and is thereby ionized. The ions are focused by the imaging lenses and enter the mass analyzer, where their mass and charge are analyzed.
Date: December 31, 1992
Creator: Villa-Aleman, E.
System: The UNT Digital Library
An apparatus for remotely handling components (open access)

An apparatus for remotely handling components

The inventive apparatus for remotely handling barlike components which define a longitudinal direction includes a gripper mechanism for gripping the component including first and second gripper members longitudinally fixedly spaced from each other and oriented parallel to each other in planes transverse to the longitudinal direction. Each gripper member includes a jaw having at least one V-groove with opposing surfaces intersecting at a base and extending radially relative to the longitudinal direction for receiving the component in an open end between the opposing surfaces. The V-grooves on the jaw plate of t he first and second gripper members are aligned in the longitudinal direction to support the component in the first and second gripper members. A jaw is rotatably mounted on and a part of each of the first and second gripper members for selectively assuming a retracted mode in which the open end of the V-groove is unobstructed and active mode in which the jaw spans the open end of the V-groove in the first and second gripper members. The jaw has a locking surface for contacting the component in the active mode to secure the component between the locking surface of the jaw and the opposing surfaces of …
Date: December 31, 1992
Creator: Szkrybalo, G. A. & Griffin, D. L.
System: The UNT Digital Library
Monitoring and analyzing waste glass compositions (open access)

Monitoring and analyzing waste glass compositions

None
Date: December 31, 1992
Creator: Schumacher, R. F.
System: The UNT Digital Library
High adherence copper plating process (open access)

High adherence copper plating process

A process is described for applying copper to a substrate of aluminum or steel by electrodeposition and for preparing an aluminum or steel substrate for electrodeposition of copper. Practice of the invention provides good adhesion of the copper layer to the substrate.
Date: December 31, 1992
Creator: Mignardot, H.
System: The UNT Digital Library
Magnetic levitation configuration incorporating levitation, guidance and linear synchronous motor (open access)

Magnetic levitation configuration incorporating levitation, guidance and linear synchronous motor

A propulsion and suspension system for an inductive repulsion type magnetically levitated vehicle which is propelled and suspended by a system which includes propulsion windings which form a linear synchronous motor and conductive guideways, adjacent to the propulsion windings, where both combine to partially encircling the vehicle-borne superconducting magnets. A three phase power source is used with the linear synchronous motor to produce a traveling magnetic wave which in conjunction with the magnets propel the vehicle. The conductive guideway combines with the superconducting magnets to provide for vehicle leviation.
Date: December 31, 1992
Creator: Coffey, H. T.
System: The UNT Digital Library
Semiconductor diode laser having an intracavity spatial phase controller for beam control and switching (open access)

Semiconductor diode laser having an intracavity spatial phase controller for beam control and switching

A high-power broad-area semiconductor laser having a intracavity spatial phase controller is disclosed. The integrated intracavity spatial phase controller is easily formed by patterning an electrical contact metallization layer when fabricating the semiconductor laser. This spatial phase controller changes the normally broad far-field emission bean, of such a laser into a single-lobed near-diffraction-limited beam at pulsed output powers of over 400 mW. Two operating modes, a thermal and a gain operating mode, exist for the phase controller, allowing for steering and switching the beam as the modes of operation are switched, and the emission beam may be scanned, for example, over a range of 1.4 degrees or switched by 8 degrees. More than one spatial phase controller may be integrated into the laser structure.
Date: December 31, 1992
Creator: Hohimer, J. P.
System: The UNT Digital Library
Microwave sintering of multiple aritcles (open access)

Microwave sintering of multiple aritcles

Disclosed are apparatus and method for producing articles of alumina and of alumina and silicon carbide in which the articles are sintered at high temperatures using microwave radiation. The articles are placed in a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.
Date: December 31, 1992
Creator: Blake, R. D. & Katz, J. D.
System: The UNT Digital Library
Compact self-contained electrical-to-optical converter/transmitter (open access)

Compact self-contained electrical-to-optical converter/transmitter

An electrical-to-optical converter/transmitter is disclosed. A first optical receiver and a second optical receiver are provided for receiving a calibrate command and a power switching signal, respectively, from a remote processor. A third receiver is provided for receiving an analog electrical signal from a transducer. A calibrator generates a reference signal in response to the calibrate command. A combiner mixes the electrical signal with the reference signal to form a calibrated signal. A converter converts the calibrated signal to an optical signal. A transmitter transmits the optical signal to the remote processor. A primary battery supplies power to the calibrator, the combiner, the converter, and the transmitter. An optically-activated switch supplies power to the calibrator, the combiner, the converter, and the transmitter in response to the power switching signal. An auxiliary battery supplies power continuously to the switch means.
Date: December 31, 1992
Creator: Seligmann, D. A.; Moss, W. C.; Valk, T. C. & Conder, A. D.
System: The UNT Digital Library
Tritium monitor (open access)

Tritium monitor

This invention is comprised of a system for continuously monitoring the concentration of tritium in an aqueous stream. The system pumps a sample of the stream to magnesium-filled combustion tube which reduces the sample to extract hydrogen gas. The hydrogen gas is then sent to an isotope separation device where it is separated into two groups of isotopes: a first group of isotopes containing concentrations of deuterium and tritium, and a second group of isotopes having substantially no deuterium and tritium. The first group of isotopes containing concentrations of deuterium and tritium is then passed through a tritium detector that produces an output proportional to the concentration of tritium detected. Preferably, the detection system also includes the necessary automation and data collection equipment and instrumentation for continuously monitoring an aqueous stream.
Date: December 31, 1992
Creator: Chastagner, P.
System: The UNT Digital Library
Open apex shaped charge-type explosive device having special disc means with slide surface thereon to influence movement of open apex shaped charge liner during collapse of same during detonation (open access)

Open apex shaped charge-type explosive device having special disc means with slide surface thereon to influence movement of open apex shaped charge liner during collapse of same during detonation

An open apex shape charge explosive device is disclosed having an inner liner defining a truncated cone, an explosive charge surrounding the truncated inner liner, a primer charge, and a disc located between the inner liner and the primer charge for directing the detonation of the primer charge around the end edge of the disc means to the explosive materials surrounding the inner liner. The disc comprises a material having one or more of: a higher compressive strength, a higher hardness, and/or a higher density than the material comprising the inner liner, thereby enabling the disc to resist deformation until the liner collapses. The disc has a slide surface thereon on which the end edge of the inner liner slides inwardly toward the vertical axis of the device during detonation of the main explosive surrounding the inner liner, to thereby facilitate the inward collapse of the inner liner. In a preferred embodiment, the geometry of the slide surface is adjusted to further control the collapse or {beta} angle of the inner liner.
Date: December 31, 1992
Creator: Murphy, M. J.
System: The UNT Digital Library
Laser patterning of laminated structures for electroplating (open access)

Laser patterning of laminated structures for electroplating

Disclosed is a process for laser patterning of a substrate so that it can be subsequently electroplated or electrolessly plated. The process utilizes a laser to treat an inactive (inert) layer formed over an active layer to either combine or remove the inactive layer to produce a patterned active layer on which electrodeposition can occur. The process is carried out by utilizing laser alloying and laser etching, and involves only a few relatively high yield steps and can be performed on a very small scale.
Date: December 31, 1992
Creator: Mayer, S. T. & Evans, L. B.
System: The UNT Digital Library
High resolution data acquisition (open access)

High resolution data acquisition

A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock pulse train and analog circuitry for generating a triangular wave synchronously with the pulse train. The triangular wave has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter counts the clock pulse train during the interval to form a gross event interval time. A computer then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.
Date: December 31, 1992
Creator: Thornton, G. W. & Fuller, K. R.
System: The UNT Digital Library
Preventive maintenance system for the photomultiplier detector blocks of pet scanners (open access)

Preventive maintenance system for the photomultiplier detector blocks of pet scanners

The present invention relates to a system for the preventive maintenance of the Photomultiplier Detector Blocks of PET Scanners. This system is used to automatically indicate the expected date of failure of a photomultiplier detector block and provide time for its replacement and maintenance in a scheduled preventive maintenance program, thus eliminating expensive unscheduled downtime of a PET Scanner due to photomultiplier failure.
Date: December 31, 1992
Creator: Levy, A. V. & Warner, D.
System: The UNT Digital Library