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Wafer Fabrication Monitoring/Control System and Method

Description: Patent relating to systems and methods for monitoring and testing patterning processes including etching, cleaning, and depositing of low k and ultra-low k dielectrics for semiconductor technologies.
Date: March 15, 2012
Creator: Chen, Jin-Jian & Chyan, Oliver M. R.
Partner: UNT College of Arts and Sciences

Tunable Polymer-Based Sonic Structures

Description: Patent relating to methods and devices for controlling the propagation of sound and particularly to tunable polymer-based sonic structures.
Date: November 14, 2013
Creator: Walker, Ezekiel; Neogi, Arup & Cai, Tong
Partner: UNT College of Arts and Sciences

Direct Graphene Growth on Metal Oxides by Molecular Epitaxy

Description: Patent relating to the controlled, layer-by-layer growth of graphene on a useful, magnetizable/and or insulating substrate using molecular beam epitaxy (MBE).
Date: June 13, 2013
Creator: Kelber, Jeffry A.
Partner: UNT College of Arts and Sciences

Graphene Magnetic Tunnel Junction Spin Filters and Methods of Making

Description: Patent relating to methods of forming a few molecule thick graphene layer on a ferromagnetic layer, at temperatures and conditions consistent with integration with silicon-based complementary metal oxide semiconductors (Si CMOS).
Date: May 25, 2012
Creator: Kelber, Jeffry A. & Zhou, Mi
Partner: UNT College of Arts and Sciences

Hydride compositions

Description: Disclosed are a composition for use in storing hydrogen and a method for making the composition. The composition comprises a mixture of two or more hydrides, each hydride having a different series of hydrogen sorption isotherms that contribute to the overall isotherms of the mixture. The hydrides are chosen so that the isotherms of the mixture have regions wherein the H equilibrium pressure increases with increasing hydrogen, preferably linearly. The isotherms of the mixture can be adjusted by selecting hydrides with different isotherms and by varying the amounts of the individual hydrides, or both. Preferably, the mixture is made up of hydrides that have isotherms with substantially flat plateaus and in nearly equimolar amounts. The composition is activated by degassing, exposing to H, and then heating below the softening temperature of any of the constituents. When the composition is used to store hydrogen, its hydrogen content can be found simply by measuring P{sub H}{sub 2} and determining H/M from the isothermic function of the composition.
Date: February 7, 1994
Creator: Lee, Myung W.
Partner: UNT Libraries Government Documents Department

Expansion joint for guideway for magnetic levitation transportation system

Description: An expansion joint that allows a guideway of a magnetic levitation transportation system to expand and contract while minimizing transients occurring in the magnetic lift and drag forces acting on a magnetic levitation vehicle traveling over the joint includes an upper cut or recess extending downwardly from the upper surface of the guideway and a non-intersecting lower cut or recess that extends upwardly from the lower surface of the guideway. The sidewalls of the cuts can be parallel to each other and the vertical axis of the guideway; the depth of the lower cut can be greater than the depth of the upper cut; and the overall combined lengths of the cuts can be greater than the thickness of the guideway from the upper to lower surface so that the cuts will overlap, but be spaced apart from each other. The distance between the cuts can be determined on the basis of the force transients and the mechanical behavior of the guideway. A second pair of similarly configured upper and lower cuts may be disposed in the guideway; the expansion joint may consist of two upper cuts and one lower cut; or the cuts may have non-parallel, diverging sidewalls so that the cuts have a substantially dove-tail shape.
Date: December 31, 1991
Creator: Rossing, T.D.
Partner: UNT Libraries Government Documents Department

Corrosion-resistant iridium-platinum anode material for high polarization application in corrosive acids

Description: The present invention relates to highly corrosion resistant components for use in an electrochemical cell. Specifically, these components are resistant to corrosion under very extreme conditions such as exposure to aqua regia in the presence of a constant current density of 100mA/m{sup 2}. The components are comprised of an iridium-platinum alloy that comprises less than 30% iridium. In a preferred embodiment of the present invention, the iridium-platinum alloy comprises 15-20% iridium. In another preferred embodiment of the present invention, the iridium-platinum alloy is deposited on the surface of an electrochemical cell component by magnetron sputtering. The present invention also relates to a method for conducting an electrochemical reaction in the presence of highly corrosive acids under a high degree of polarization wherein the electrochemical cell comprises a component, preferably the anode, containing an iridium-platinum alloy that comprises less than 30% iridium.
Date: September 8, 1993
Creator: Farmer, J.; Summers, L. & Lewis, P.
Partner: UNT Libraries Government Documents Department

Wedge and spring assembly for securing coils in electromagnets and dynamoelectric machines

Description: A wedge and spring assembly for use in electromagnets or dynamoelectric machines having a housing with an axis therethrough and a plurality of coils supported on salient poles that extend radially inward from the housing toward the housing axis to define a plurality of interpole spaces, respectively between the housing and adjacent coils, the interpole spaces each extending in a direction generally parallel to the housing axis. The wedge and spring assembly includes a nonmagnetic retainer spring and a nonmagnetic wedge. The retainer spring is formed to fit into one of the interpole spaces, and has juxtaposed ends defining between them a slit extending in a direction generally parallel to the housing axis. The wedge for insertion into the slit provides an outwardly directed force on respective portions of the juxtaposed ends defining the slit to expand the slit so that respective portions of the retainer spring engage areas of the coils adjacent thereto, thereby resiliently holding the coils against their respective salient poles. Preferably, the spring retainer and wedge are self-locking wherein wedge is fabricated from a material softer than a material the retainer spring is fabricated from, so that the wedge is securely retained in the slit. The retainer spring is generally triangular shaped to fit within the interpole space and fabricated from berryllium-copper alloy, and the wedge is generally T-shaped and fabricated from aluminum. Alternatively, a wedge and spring assembly includes a wedge having divergent sloped surfaces in which each surface and the respective juxtaposed ends of the retainer spring are angled relative to one another so that the wedge is securely retained in the slit by friction existing between its sloped surfaces and the juxtaposed ends of the retaining spring.
Date: December 31, 1994
Creator: Lindner, M. & Cottingham, J.G.
Partner: UNT Libraries Government Documents Department

Use of CHELEX-100{reg_sign} for radionuclide purification

Description: A method for selectively removing yttrium-90 from its parent strontium-90 contained in an environmental sample includes loading the sample onto a column containing a chelating ion-exchange resin capable of retaining yttrium-90; washing the column with a solution capable of removing strontium, calcium and other contaminants from the yttrium-90 fraction retained on the column; removing excess acetate salts from the column; eluting yttrium-90 solution from the column and adjusting the pH of this solution to about 2.7; filtering the yttrium-90 solution and weighting this solution for gravimetric yield; and, counting the yttrium-90 containing solution with a radiological counter for a time sufficient to achieve the statistical accuracy desired. It is preferred that the chelating ion-exchange resin is a bidente ligand having the chemical name iminodiacetic acid mounted on a divinyl benzene substrate, converted from sodium form to ammonia form. Its name is Chelex-100{reg_sign}.
Date: December 1993
Creator: Huntley, M. W.
Partner: UNT Libraries Government Documents Department

Reactive multilayer synthesis of hard ceramic foils and films

Description: Disclosed is method for synthesizing hard ceramic materials such as carbides, borides and aluminides, particularly in the form of coatings provided on another material so as to improve the wear and abrasion performance of machine tools, for example. Method involves the sputter deposition of alternating layers of reactive metals with layers of carbon, boron, or aluminum and the subsequent reaction of the multilayered structure to produce a dense crystalline ceramic. The material can be coated on a substrate or formed as a foil which can be coiled as a tape for later use.
Date: December 31, 1993
Creator: Makowiecki, D.M. & Holt, J.B.
Partner: UNT Libraries Government Documents Department

Reusable vibration resistant integrated circuit mounting socket

Description: This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and hold it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuit lead can be removed from the socket without damage either to the lead or to the socket components.
Date: December 31, 1993
Creator: Evans, C.N.
Partner: UNT Libraries Government Documents Department

Separation of strontium from fecal matter

Description: The present invention relates to a method of separating strontium, and, more particularly, to a method of separating strontium from a sample of biomass potentially contaminated with various radionuclides. Radioactive strontium is a radionuclide which represents a hazard to man because of its long half-life and, if ingested, its tendency to be retained in the human body. In the event that radionuclides such as strontium or various actinides are ingested, it is desirable to monitor the discharge or release of these radionuclides from the human body through analysis of fecal matter. In laboratories and other facilities where potential for radionuclide contamination exists, fecal analysis for strontium is routinely conducted for individuals who are terminating from their position or are suspected of having been contaminated with radionuclides. Methods for separating and analyzing radioactive actinides from a biomass sample are well known and have been extensively developed for the US Department of Energy. These methods, described in the Department`s internal procedure, USDOE, RESL/ID, A-16, 1981, as well as in US Patent 5,190,881, involve the use of an iron phosphate precipitation step to separate actinides from a solution, or supernate. However, there are no established procedures for the separation of strontium from a biomass sample wherein an iron phosphate precipitation step is involved.
Date: December 31, 1994
Creator: Kester, D.K.
Partner: UNT Libraries Government Documents Department

Solenoid and monocusp ion source

Description: An ion source which generates ions having high atomic purity incorporates a solenoidal magnetic field to increase the electron path length. In a sealed envelope, electrons emitted from a cathode traverse the magnetic field lines of a solenoid and a monocusp magnet between the cathode and a reflector at the monocusp. As electrons collide with gas, the molecular gas forms a plasma. An anode grazes the outer boundary of the plasma. Molecular ions and high energy electrons remain substantially on the cathode side of the cusp, but as the ions and electrons are scattered to the aperture side of the cusp, additional collisions create atomic ions. The increased electron path length allows for smaller diameters and lower operating pressures.
Date: December 31, 1995
Creator: Brainard, J.P.; Burns, E.J.T. & Draper, C.H.
Partner: UNT Libraries Government Documents Department

Wafer-scale charge isolation technique

Description: An apparatus and method are described which improve the performance of charge-coupled devices (CCD) in the presence of ionizing radiation. The invention is a wafer scale charge isolation technique which inhibits or reduces the flow of electrons created by the passage of ionizing radiation in the bulk regions of a silicon CCD. The technique has been tested in a device designed for operating in the infra-red wavelength band. The technique prevents charge from reaching the active charge collection volume of a pixel in a CCD.
Date: December 31, 1994
Creator: Colella, N.J. & Kimbrough, J.R.
Partner: UNT Libraries Government Documents Department

Strain-optic voltage monitor

Description: A voltage monitor which uses the shift in absorption edge of crystalline material to measure strain resulting from electric field-induced deformation of piezoelectric or electrostrictive material, providing a simple and accurate means for measuring voltage applied either by direct contact with the crystalline material or by subjecting the material to an electric field.
Date: December 31, 1995
Creator: Weiss, J.D.
Partner: UNT Libraries Government Documents Department