Abstract: An integrator-multiplier-integrator circuit scheme usable in transverse fers, a transverse filter employing such a circuit, and a method for using each. The multiplier-integrator-multiplier has a capacitatively loaded integrating amplifier fed by a transistor. The current through the transistor, and hence the time it takes to charge the integrating capacitor, depends largely on the bias of the transistor, not the size of the capacitor, permitting one to set and control integration time by setting the transistor's parameters, and controlling its bias, effectively controlling integration time by us of only one semiconductor device. An additional circuit for auto-zeroing (i.e. canceling quiescent offset) increases adaptivity of the circuit. Preferably the phase of inputs to the first multiplier is made selectably variable to minimize phase difference at the multiplier, thus increasing circuit stability.
Type:
Grant
Filed:
November 6, 1995
Date of Patent:
July 14, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: A novel organoboron polymer and its method of preparation is claimed. The organoboron polymer has a backbone having a repeating unit comprising at least one carboranyl group, at least two acetylenic groups, and one or more silyl or siloxanyl groups.
Type:
Grant
Filed:
November 7, 1994
Date of Patent:
July 14, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: Hydrogen and/or carbon impurities are removed from chalcogenide or chalcoide glasses by the addition of a halide, such as TeCl.sub.4, to the batch composition. During melting of the batch composition, the metal halide reacts with the hydrogen and/or carbon impurities to form a hydrogen halide and/or carbon tetrahalide gas and a metal which becomes incorporated into the chalcogen-based glass. Useful halides include halides of sulfur, selenium, tellurium, polonium, or halides of a metal (such as aluminum, magnesium, zirconium, or a mixture thereof) that forms a stable oxide. Mixed metal halides may also be used. The glass melt is then distilled, outgassed, homogenized, fined, and annealed. An apparatus specially designed for making a fiber preform by the above process is also described. An annealed preform made by this method may be drawn into a low-loss fiber in the 2 .mu.m to 12 .mu.m range.
Type:
Grant
Filed:
June 26, 1996
Date of Patent:
July 14, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Jasbinder S. Sanghera, Vinh Q. Nguyen, Ishwar D. Aggarwal
Abstract: A composite structure includes a self-supporting substrate and a thermal barrier coating of zirconia stabilized with scandia and yttria. A method of protecting the surface of a self-supporting substrate from degradation caused by exposure to temperatures above 1200.degree. C. includes the step of applying to the surface a coating of zirconia stabilized with scandia and yttria.
Type:
Grant
Filed:
October 31, 1996
Date of Patent:
July 14, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: An optical fiber termination connector includes an elongated structure with chamber extending therethrough open at both ends, a fiber disposed in the chamber and spaced therefrom, a solid first material disposed in the chamber around the fiber, and an air gap in the chamber around the end of the fiber. The process includes the steps of locating a fiber in a chamber disposed vertically, with the end of the fiber extending beyond the lower portion of chamber; dipping a lower portion of the chamber into a first material in liquid form so that the first material enters the lower portion of the chamber to a level below an exit port located in the lower portion of the chamber; solidifying the first material disposed in and around the chamber and the fiber; above the solid first material; polishing the lower end of the fiber until it is flush with the chamber at the lower thereof; and removing the first material to form an air gap between the fiber and the lower portion of the chamber.
Type:
Grant
Filed:
October 30, 1996
Date of Patent:
July 7, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Lynda E. Busse, Frederic H. Kung, Jasbinder S. Sanghera, Ishwar D. Aggarwal
Abstract: Hg,Tl-based superconductors are produced by HIPping. A new superconducting phase, having a double (Hg,Tl)-layer and the nominal composition:(Hg.sub.1-x Tl.sub.x).sub.2 (Ba.sub.1-a Sr.sub.a).sub.2 (Ca.sub.1-b Y.sub.b).sub.2 Cu.sub.3 O.sub.zwhere 0.ltoreq.x.ltoreq.0.95, 0.ltoreq.a.ltoreq.1, 0.ltoreq.b.ltoreq.1, and z is sufficient to provide said phase with a resistive and magnetic superconducting transition of 100K or above, can be produced. Either precursor oxides, or partially or fully reacted mixed oxides, can be used in the HIPping mixture.
Type:
Grant
Filed:
April 28, 1995
Date of Patent:
July 7, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Louis E. Toth, William Lechter, Earl F. Skelton, Michael Osofsky
Abstract: O-nitrobenzyl analogs that include a photoremovable protecting group that resists the nonspecific adsorption of biomolecules and a linking group for attaching the o-nitrobenzyl analog to a substrate are disclosed. Also disclosed are methods for using o-nitrobenzyl analogs for creating patterned arrays of anti-ligands on a substrate so that a plurality of bioassays can be conducted simultaneously. In particular, the compounds disclosed are o-nitrobenzyl-polyethylene glycol-silanes, wherein the silane group serves to attach the compound to a substrate, the polyethylene glycol group resists the nonspecific adsorption of biomolecules. The o-nitrobenzyl group provides a photoactivatable functionality that allows the polyethylene glycol group to be selectively removed upon exposure to UV radiation and be replaced by an anti-ligand.
Type:
Grant
Filed:
February 10, 1997
Date of Patent:
June 30, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
David W. Conrad, Sara K. Golightley, John C. Bart
Abstract: A field emitter is disclosed comprising a graded electron affinity surface ayer. The graded electron affinity layer provides for increased transconductance, reduced energy distribution of emitted electrons, reduced noise and increased uniformity in its operation.
Type:
Grant
Filed:
July 3, 1995
Date of Patent:
June 30, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Jonathan L. Shaw, Kevin Jensen, Henry F. Gray
Abstract: The use of lactic acid or its derivative in compositions to etch or polish materials containing indium phosphide results in treated surfaces that have reduced surface roughness compared to the surfaces treated with compositions devoid of lactic acid or its derivative. Indium phosphide surfaces treated with compositions containing lactic acid can have treated surfaces that are smooth or mirror-like, meaning that surface irregularities thereon are less than about 50 .ANG..
Type:
Grant
Filed:
May 8, 1996
Date of Patent:
June 30, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Kiki Ikossi-Anastasiou, Steve C. Binari, J. Brad Boos, Galina Kelner
Abstract: The wick-interrupt temperature controlling heat pipe (WITCH) is a device for controlling the temperature of spacecraft temperature-sensitive, heat dispensing devices. A heat transporting working fluid is conveyed in saturated equilibrium with its vapor across a discontinuous internal capillary liquid wick, within a tubular cylindrical pressure vessel, from a condenser section to an evaporator section located on either side of the discontinuity. When the temperature within the WITCH rises to a predetermined level, a sliding wick located within the internal capillary liquid wick is inserted across the discontinuity by a temperature sensitive control rod, thereby allowing the heat transporting working fluid to circulate from the condenser section wick to the evaporator section wick. In this configuration, the WITCH operates identically to the "constant-conductance heat pipe" commonly used.
Type:
Grant
Filed:
September 12, 1996
Date of Patent:
June 30, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: The present invention is a process for making a honeycomb structure of a ected material, having the steps: (a) disposing molten material in a melt container disposed over a mold, where the melt container has an opening for releasing molten material into the mold, where the mold is shaped for molding the honeycomb structure; (b) moving the melt container relative to the mold, where the molten material flows out of the opening into the mold; and (c) removing the mold from the material. Another aspect of the invention is an apparatus for making a honeycomb structure of a selected material, including: (a) a mold shaped for molding the honeycomb structure; (b) a melt container, disposed over the mold, having an opening for releasing molten material into the mold; and (c) a conveyor, for moving the melt container relative to the mold as the melt container releases the molten material into the mold.
Type:
Grant
Filed:
November 7, 1996
Date of Patent:
June 23, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: A silicon carbide semiconductor material; and method of making same, in which a doped film of 3C-silicon carbide is grown heteroepitaxially on a 6H-silicon carbide material. Growth occurs at 1200.degree. C. or less, and produces a heterolayer having a reduced bandgap, and hence reduced contact resistance, but which is fabricatable with the less expensive equipment commonly used to fabricate silicon based semiconductors.
Type:
Grant
Filed:
January 17, 1995
Date of Patent:
June 16, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Vladamir A. Dmitriev, Kenneth G. Irvine, Michael Spencer, Galina Kelner
Abstract: Inclusion complexes have an organic guest molecule dye with an electron dr portion, an electron acceptor portion and a hydrophobic tail portion disposed within an organic carbohydrate host molecule. The dye in the inclusion complexes has improved thermal stability compared to itself. The complexes can be used to form a solution-cast film disposed on a substrate wherein the film thickness is up to about 20 microns and the film is made of anisotropically self-aligned (self-poled) inclusion complexes.
Type:
Grant
Filed:
June 14, 1995
Date of Patent:
June 9, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Oh-Kil Kim, Ling-Siu Choi, Heyi Zhang, Xue Hua He, Yan Huh Shih
Abstract: Nanostructured metal powders and films are made by dissolving or wetting a metal precursor in an alcoholic solvent. The resulting mixture is then heated to reduce the metal precursor to a metal precipitate. The precipitated metal may be isolated, for example, by filtration.
Type:
Grant
Filed:
November 30, 1995
Date of Patent:
June 2, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Gan-Moog Chow, Paul E. Schoen, Lynn K. Kurihara
Abstract: Viscous, liquid hexafluoroisopropanol-siloxane polymers having the basic structure: ##STR1## wherein R.sub.1 is a monovalent hydrocarbon radical selected from the group consisting of C.sub.1 -C.sub.6 alkyl groups; cyclohexyl groups and phenyl groups;R.sub.2 is ##STR2## wherein m=1 to 4; and n is an integer greater than 1, are useful for rapid, reversible vapor sorption, especially for hydrogen bond accepting vapors.
Type:
Grant
Filed:
May 27, 1994
Date of Patent:
May 26, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: A method of preparing a linear inorganic-organic hybrid polymer includes the steps of cooling a reaction medium to a first starting temperature below the ambient temperature and not less than about -10.degree. C., adding n-butyllithium and an organic compound capable of reacting with n-butyllithium to form an organo-dilithium compound to the reaction medium, allowing the organic compound and the n-butyllithium to react to form an organo-dilithium compound while allowing the reaction medium to warm, cooling the reaction medium to a second starting temperature below the ambient temperature and not less than about -10.degree. C.
Type:
Grant
Filed:
November 27, 1996
Date of Patent:
May 26, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: A mirrorless, distributed-feedback (DFB), ultraviolet, tunable, narrow-liidth, solid state laser for remote sensing and medical applications is disclosed. Optical pumping in the DFB laser is accomplished using a frequency quadrupled, 10 Hz., Q-switched, Nd:YAG laser operating at 266 nm. The pump beam is diffracted off a grating (2400 grooves per mm.) into two parts. The two beams are subsequently recombined at the side face of the Ce:doped crystal (8 mm.times.8 mm.times.30 mm) at an angle of about 2.theta.(about 81 degrees). The resulting spatially periodic excitation within the Ce-doped gain medium due to the interferring pump beams determines the operating wavelength of the DFB laser.
Type:
Grant
Filed:
November 15, 1996
Date of Patent:
May 19, 1998
Assignee:
The United States of America as represented by the Sectary of the Navy.
Abstract: A sensing apparatus and related method for sensing strain between fiber Bragg grating sensors inscribed in an optical fiber. The fiber is inscribed with a first fiber Bragg grating sensor and a second fiber Bragg grating sensor. A strain detection unit detects strain between the first fiber Bragg grating sensor and the second fiber Bragg grating sensor based on the optical propagation time of light projected into the fiber and reflected by the first fiber Bragg grating sensor and the optical propagation time of light projected into the fiber and reflected by the second fiber Bragg grating sensor. More specifically, light projected into the fiber is modulated with an RF signal. A phase change of the RF signal is determined from the light projected into the fiber and reflected by the first fiber Bragg grating sensor and from the light projected into the fiber and reflected by the second fiber Bragg grating sensor.
Type:
Grant
Filed:
September 19, 1995
Date of Patent:
May 5, 1998
Assignee:
United States of American as represented by the Secretary of the Navy
Abstract: A high-efficiency fluorescent emitter includes an excitation source and a w phonon host doped with erbium. The emitter can be used as a lasing medium or as a phosphor. Typical hosts include RcX.sub.3 and chalcogenide glasses, wherein Rc is yttrium, gadolinium, lutetium, lanthanum or a mixture thereof, and X is a halogen or a mixture of halogens.
Type:
Grant
Filed:
January 31, 1996
Date of Patent:
May 5, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Steven R. Bowman, Barry J. Feldman, Leslie B. Shaw
Abstract: Microspheres, of controllable shape and size, encapsulating active ingredients, are made by the internally controlled gelation of an emulsion including a water-soluble polysaccharide, a salt of a di- or trivalent metal cation, a polymerization inhibitor, water, a water-immiscible solvent (as a non-aqueous phase), and the active ingredient. The components of the aqueous phase, containing the water-soluble polysaccharide, polymerization inhibitor, di- or trivalent metal salt, active substance, and water, are blended together. This aqueous phase is then gradually mixed with the oil phase and agitated to form an emulsion. After sufficient time for solidification, the emulsion is broken and the resulting microspheres are collected. The active ingredient may be various substances, including live microorganisms.
Type:
Grant
Filed:
December 26, 1995
Date of Patent:
April 28, 1998
Assignee:
The United States of America as represented by the Secretary of the Navy