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Method of solubilizing phthalocyanines and metallophthalocyanines

Description: A one-step method of manufacturing soluble phthalocyanines and metallophthalocyanines, like zinc phthalocyanine, by converting a phthalocyanine or a metallophthalocyanine to a trialkylsilyl-substituted derivative is disclosed. The phthalocyanine or metallophthalocyanine is converted to a soluble trialkylsilyl-substituted derivative by interacting the phthalocyanine or metallophthalocyanine with an active metal amide, like lithium 2,2,6, 6-tetra-methylpiperidide, and a halotrialkylsilane, like c… more
Date: June 1, 1990
Creator: Rathke, Jerome W.; Chen, Michael J. & Fendrick, Carol M.
Partner: UNT Libraries Government Documents Department
open access

Process of making cryogenically cooled high thermal performance crystal optics

Description: A method for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N{sub 2} is pumped through the porous material at a sub-cooled cryogenic inlet temperature an… more
Date: June 29, 1990
Creator: Kuzay, Tuncer M.
Partner: UNT Libraries Government Documents Department
open access

Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy

Description: This invention is comprised of a method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the stat… more
Date: August 15, 1990
Creator: Brennan, T. M.; Hammons, B. E. & Tsao, J. Y.
Partner: UNT Libraries Government Documents Department
open access

Separation of Metals by Supported Liquid Membranes

Description: A supported liquid membrane system for the separation of a preselected chemical species within a feedstream, preferably an aqueous feedstream, includes a feed compartment containing a feed solution having at least one preselected chemical species therein, a stripping compartment containing a stripping solution therein, and a microporous polybenzimidazole membrane situated between the compartments, the microporous polybenzimidazole membrane containing an extractant mixture selective for the pres… more
Date: December 31, 1990
Creator: Takigawa, Doreen Y.
Partner: UNT Libraries Government Documents Department
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Method for Improving the Growth of Cadmium Telluride on a Gallium Arsenide Substrate

Description: A method for preparing a gallium arsenide substrate, prior to growing a layer of cadmium telluride on a support surface thereof. The preparation includes the steps of cleaning the gallium arsenide substrate and thereafter forming prepatterned shapes on the support surface of the gallium arsenide substrate. The layer of cadmium telluride then grown on the prepared substrate results in dislocation densities of approximately 1{times}10{sup 6}/cm{sup 2} or less. The prepatterned shapes on the suppo… more
Date: December 31, 1990
Creator: Reno, John L.
Partner: UNT Libraries Government Documents Department
open access

Improved morphology in electrochemically grown conducting polymer films

Description: A conducting polymer film with an improved space filling is formed on a metal electrode surface. A self-assembling monolayer is formed directly on the metal surface where the monolayer has a first functional group that binds to the metal surface and a second chemical group that forms a chemical bonding site for molecules forming the conducting polymer. The conducting polymer is then conventionally deposited by electrochemical deposition. In one example, a conducting film of polyaniline is forme… more
Date: December 31, 1990
Creator: Rubinstein, I.; Gottesfeld, S. & Sabatani, E.
Partner: UNT Libraries Government Documents Department
open access

Passive decay heat removal system for water-cooled nuclear reactors

Description: This document describes passive decay-heat removal system for a water-cooled nuclear reactor which employs a closed heat transfer loop having heat-exchanging coils inside an open-topped, insulated evaporator located inside the reactor vessel, below its normal water level, in communication with a condenser located outside of containment and exposed to the atmosphere. The heat transfer loop is located such that the evaporator is in a position where, when the water level drops in the reactor, it w… more
Date: December 31, 1990
Creator: Forseberg, C. W.
Partner: UNT Libraries Government Documents Department
open access

Water and UV degradable lactic acid polymers

Description: A water and UV light degradable copolymer of monomers of lactic acid and a modifying monomer selected from the class consisting of ethylene and polyethylane glycols (PVB 6/22/90), propylene and and polypropylene (PVB 6/22/90) glycols, P-dioxanone, 1, 5 dioxepan-2-one, 1,4 -oxathialan-2-one, 1,4-dioxide and mixtures thereof. These copolymers are useful for waste disposal and agricultural purposes. Also disclosed is a water degradable blend of polylactic acid or modified polylactic acid and high … more
Date: June 26, 1990
Creator: Bonsignore, P. V. & Coleman, R. D.
Partner: UNT Libraries Government Documents Department
open access

Production of aluminum-26

Description: This invention is a method of producing Al-26 from potassium chloride by exposing it to a proton beam in order to break potassium and chlorine atoms into smaller pieces, which include Al-26. The Al-26 is isolated from the potassium chloride and substances produced by the beam by means of extraction and ion exchange.
Date: December 31, 1990
Creator: Steinkruger, F. J. & Phillips, D. R.
Partner: UNT Libraries Government Documents Department
open access

Process of making cryogenically cooled high thermal performance crystal optics

Description: A method for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N{sub 2} is pumped through the porous material at a sub-cooled cryogenic inlet temperature an… more
Date: June 29, 1990
Creator: Kuzay, T. M.
Partner: UNT Libraries Government Documents Department
open access

Process for forming one or more substantially pure layers in substrate material using ion implantation

Description: The method comprises selecting an implantable element and a substrate material to be implanted which, at the implant/anneal temperatures, have limited mutual solubility and have no intermediate phases formed. In an example, Be is implanted with 11 {times}10{sup 17} Al/cm{sup 2} at 200 keV and then annealed for 1 h at 500 C. Rutherford backscattering shows that layer formation occurred during the anneal. SEM shows rectangular Be defects in the Al layer. Other examples of implantable elements and… more
Date: December 31, 1990
Creator: Musket, R. G.; Brown, D. W. & Munir, Z. A.
Partner: UNT Libraries Government Documents Department
open access

Supported liquid membrane system

Description: A cell apparatus for a supported liquid membrane including opposing faceplates, each having a spirally configured groove, an inlet groove at a first end of the spirally configured groove, and an outlet groove at the other end of the spirally configured groove, within the opposing faces of the faceplates, a microporous membrane situated between the grooved faces of the faceplates, said microporous membrane containing an extractant mixture selective for a predetermined chemical species within the… more
Date: December 31, 1990
Creator: Takigawa, D. Y. & Bush, H. Jr.
Partner: UNT Libraries Government Documents Department
open access

Extrusion of metal oxide superconducting wire, tube or ribbon

Description: A process and apparatus for extruding a superconducting metal oxide composition YBa{sub 2}Cu{sub 3}O{sub 7-x} provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6--85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for … more
Date: December 31, 1990
Creator: Dusek, Joseph T.
Partner: UNT Libraries Government Documents Department
open access

High current pulse transmission cable

Description: This invention is comprised of a transmission cable for carrying high current pulses in which an even numbered plurality of electrical conductors surrounds a central ground conductor. Each electrical conductor is connected so that it at any instant in time it will carry current of opposite polarity to the polarity carried by adjacent conductors. This arrangement cancels practically all of the external fields generated by current in the conductors.
Date: September 28, 1990
Creator: Parsons, W. M.
Partner: UNT Libraries Government Documents Department
open access

Process for alloying uranium and niobium

Description: Alloys such as U-6Nb are prepared by forming a stacked sandwich array of uranium sheets and niobium powder disposed in layers between the sheets, heating the array in a vacuum induction melting furnace to a temperature such as to melt the uranium, holding the resulting mixture at a temperature above the melting point of uranium until the niobium dissolves in the uranium, and casting the uranium-niobium solution. Compositional uniformity in the alloy product is enabled by use of the sandwich str… more
Date: December 31, 1990
Creator: Holcombe, Cressie E.; Northcutt, Walter G.; Masters, David R. & Chapman, Lloyd R.
Partner: UNT Libraries Government Documents Department
open access

Electrical safety device

Description: This invention consists of an electrical safety device for use in power tools that is designed to automatically discontinue operation of the power tool upon physical contact of the tool with a concealed conductive material. A step down transformer is used to supply the operating power for a disconnect relay and reset delay. When physical contact is made between the power tool and the conductive material, an electrical circuit through the disconnect relay is completed and the operation of the po… more
Date: September 6, 1990
Creator: White, D. B.
Partner: UNT Libraries Government Documents Department
open access

Calcination and solid state reaction of ceramic-forming components to provide single-phase ceramic product having fine particle size

Description: The invention consists of an improved method for the preparation of single phase, fine grained ceramic materials from precursor powder mixtures where at least one of the components of the mixture is an alkali earth carbonate. The process consists of heating the precursor powders in a partial vacuum under flowing oxygen and under conditions where the partial pressure of CO{sub 2} evolved during the calcination is kept to a very low level relative to the oxygen. The process has been found particu… more
Date: September 28, 1990
Creator: Balachandran, U.; Poeppel, R. B.; Emerson, J. E. & Johnson, S. A.
Partner: UNT Libraries Government Documents Department
open access

Silicon nitride reinforced with molybdenum disilicide

Description: Compositions of matter comprised of silicon nitride and molybdenum disilicide and methods of making the compositions, where the molybdenum disilicide is present in amounts ranging from about 5 to about 50 vol%.
Date: December 31, 1990
Creator: Petrovic, John J. & Honnell, Richard E.
Partner: UNT Libraries Government Documents Department
open access

Production of hollow aerogel microspheres

Description: A method is described for making hollow aerogel microspheres of 800--1200{mu} diameter and 100--300{mu} wall thickness by forming hollow alcogel microspheres during the sol/gel process in a catalytic atmosphere and capturing them on a foam surface containing catalyst. Supercritical drying of the formed hollow alcogel microspheres yields hollow aerogel microspheres which are suitable for ICF targets.
Date: December 31, 1990
Creator: Upadhye, Ravindra S. & Henning, Sten A.
Partner: UNT Libraries Government Documents Department
open access

Method for preparing homogeneous single crystal ternary III-V alloys

Description: A method for producing homogenous single crystal III--V ternary alloys of high crystal perfection using a floating crucible system in which the outer crucible holds a ternary alloy of the composition desired to be produced in the crystal and an inner floating crucible having a narrow, melt-passing channel in its bottom wall holds a small quantity of melt of a pseudo-binary liquidus composition which would freeze into the desired crystal composition. The alloy of the floating crucible is maintai… more
Date: August 14, 1990
Creator: Ciszek, T. F.
Partner: UNT Libraries Government Documents Department
open access

Highly conductive electrolyte composites and method of fabrication thereof

Description: An electrolyte composite is manufactured by pressurizing a mixture of ionically conductive glass and an ionically conductive compound at between 12,000 and 24,000 pounds per square inch to produce a pellet. The resulting pellet is then sintered at relatively lower temperatures (800{degrees}C--1200{degrees}C), for example 1000{degrees}C, than are typically required (1400{degrees}C) when fabricating single constituent ceramic electrolytes. The resultant composite is 100 percent conductive at 250{… more
Date: July 17, 1990
Creator: Hash, M. C. & Bloom, I. D.
Partner: UNT Libraries Government Documents Department
open access

Solid-state NMR imaging system

Description: An accessory for use with a solid-state NMR spectrometer includes a special imaging probe with linear, high-field strength gradient fields and high-power broadband RF coils using a back projection method for data acquisition and image reconstruction, and a real-time pulse programmer adaptable for use by a conventional computer for complex high speed pulse sequences.
Date: December 31, 1990
Creator: Gopalsami, N.; Dieckman, S. L. & Ellingson, W. A.
Partner: UNT Libraries Government Documents Department
open access

Selective epitaxy using the GILD process

Description: The present invention comprises a method of selective epitaxy on a semiconductor substrate. The present invention provides a method of selectively forming high quality, thin GeSi layers in a silicon circuit, and a method for fabricating smaller semiconductor chips with a greater yield (more error free chips) at a lower cost. The method comprises forming an upper layer over a substrate, and depositing a reflectivity mask which is then removed over selected sections. Using a laser to melt the unm… more
Date: December 31, 1990
Creator: Weiner, K. H.
Partner: UNT Libraries Government Documents Department
open access

High density hexagonal boron nitride prepared by hot isostatic pressing in refractory metal containers

Description: Boron nitride powder with less than or equal to the oxygen content of starting powder (down to 0.5% or less) is hot isostatically pressed in a refractory metal container to produce hexagonal boron nitride with a bulk density greater than 2.0 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a cansister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1800{degrees}… more
Date: December 31, 1990
Creator: Hoenig, C. L.
Partner: UNT Libraries Government Documents Department
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