Patents Represented by Attorney, Agent or Law Firm Ken Richardson
  • Patent number: 5757474
    Abstract: A method and apparatus for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby.
    Type: Grant
    Filed: June 28, 1995
    Date of Patent: May 26, 1998
    Assignee: Midwest Research Institute
    Inventors: Bhushan L. Sopori, Larry C. Allen, Craig Marshall, Robert C. Murphy, Todd Marshall
  • Patent number: 5747099
    Abstract: A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: May 5, 1998
    Assignee: Midwest Research Institute
    Inventor: Richard D. Blaugher
  • Patent number: 5747967
    Abstract: A method and apparatus for maximizing the electric power output of a photovoltaic array connected to a battery where the voltage across the photovoltaic array is adjusted through a range of voltages to find the voltage across the photovoltaic array that maximizes the electric power generated by the photovoltaic array and then is held constant for a period of time. After the period of time has elapsed, the electric voltage across the photovoltaic array is again adjusted through a range of voltages and the process is repeated. The electric energy and the electric power generated by the photovoltaic array is delivered to the battery which stores the electric energy and the electric power for later delivery to a load.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: May 5, 1998
    Assignee: Midwest Research Institute
    Inventors: Eduard Muljadi, Roger W. Taylor
  • Patent number: 5731031
    Abstract: A process for chemical bath deposition of selenide and sulfide salts as films and powders employable as precursors for the fabrication of solar cell devices. The films and powders include (1) Cu.sub.x Se.sub.n, wherein x=1-2 and n=1-3; (2) Cu.sub.x Ga.sub.y Se.sub.n, wherein x=1-2, y=0-1 and n=1-3; (3) Cu.sub.x In.sub.y Se.sub.n, wherein x=1-2.27, y=0.72-2 and n=1-3; (4) Cu.sub.x (InGa).sub.y Se.sub.n, wherein x=1-2.17, y=0.96-2 and n=1-3; (5) In.sub.y Se.sub.n, wherein y=1-2.3 and n=1-3; (6) Cu.sub.x S.sub.n, wherein x=1-2 and n=1-3; and (7) Cu.sub.x (InGa).sub.y (SeS).sub.n, wherein x=1-2, y=0.07-2 and n=0.663-3.
    Type: Grant
    Filed: December 20, 1995
    Date of Patent: March 24, 1998
    Assignee: Midwest Research Institute
    Inventors: Raghu Nath Bhattacharya, Rommel Noufi, Li Wang
  • Patent number: 5726053
    Abstract: The invention relates to microorganisms which normally do not ferment pentose sugar and which are genetically altered to ferment pentose sugar to produce ethanol, and fermentation processes utilizing the same. Examples include Zymomonas mobilis which has been transformed with combinations of E. coli genes for xylose isomerase, xylulokinase, transaldolase, transketolase, L-arabinose isomerase, L-ribulokinase, and L-ribulose-5-phosphate 4-epimerase. Expression of the added genes are under the control of Zymomonas mobilis promoters. These newly created microorganisms are useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol.
    Type: Grant
    Filed: April 14, 1995
    Date of Patent: March 10, 1998
    Assignee: Midwest Research Institute
    Inventors: Stephen K. Picataggio, Min Zhang, Christina K. Eddy, Kristine A. Deanda
  • Patent number: 5716736
    Abstract: The present invention relates to the composition of a solid lithium-ion electrolyte based on the Li.sub.2 O--CeO.sub.2 --SiO.sub.2 system having good transparent characteristics and high ion conductivity suitable for uses in lithium batteries, electrochromic devices and other electrochemical applications.
    Type: Grant
    Filed: October 6, 1995
    Date of Patent: February 10, 1998
    Assignee: Midwest Research Institute
    Inventors: Ji-Guang Zhang, David K. Benson, C. Edwin Tracy
  • Patent number: 5711803
    Abstract: A process for the preparation of a semiconductor film. The process comprises depositing nanoparticles of a semiconductor material onto a substrate whose surface temperature during nanoparticle deposition thereon is sufficient to cause substantially simultaneous fusion of the nanoparticles to thereby coalesce with each other and effectuate film growth.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: January 27, 1998
    Assignee: Midwest Research Institute
    Inventors: Martin Pehnt, Douglas L. Schulz, Calvin J. Curtis, David S. Ginley
  • Patent number: 5712142
    Abstract: The gene encoding Acidothermus cellulolyticus E1 endoglucanase is cloned and expressed in Pichia pastoris. A new modified E1 endoglucanase enzyme comprising the catalytic domain of the full size E1 enzyme demonstrates enhanced thermostability and is produced by two methods. The first method of producing the new modified E1 is proteolytic cleavage to remove the cellulose binding domain and linker peptide of the full size E1. The second method of producing the new modified E1 is genetic truncation of the gene encoding the full size E1 so that the catalytic domain is expressed in the expression product.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: January 27, 1998
    Assignee: Midwest Research Institute
    Inventors: William S. Adney, Steven R. Thomas, John O. Baker, Michael E. Himmel, Yat-Chen Chou
  • Patent number: 5712187
    Abstract: A method of depositing a semiconductor material on a substrate. The method sequentially comprises (a) providing the semiconductor material in a depositable state such as a vapor for deposition on the substrate; (b) depositing the semiconductor material on the substrate while heating the substrate to a first temperature sufficient to cause the semiconductor material to form a first film layer having a first grain size; (c) continually depositing the semiconductor material on the substrate while cooling the substrate to a second temperature sufficient to cause the semiconductor material to form a second film layer deposited on the first film layer and having a second grain size smaller than the first grain size; and (d) raising the substrate temperature, while either continuing or not continuing to deposit semiconductor material to form a third film layer, to thereby anneal the film layers into a single layer having favorable efficiency characteristics in photovoltaic applications.
    Type: Grant
    Filed: November 9, 1995
    Date of Patent: January 27, 1998
    Assignee: Midwest Research Institute
    Inventors: Xiaonan Li, Peter Sheldon
  • Patent number: 5712133
    Abstract: The invention relates to microorganisms which normally do not ferment pentose sugar and which are genetically altered to ferment pentose sugar to produce ethanol, and fermentation processes utilizing the same. Examples include Zymomonas mobilis which has been transformed with combinations of E. coli genes for xylose isomerase, xylulokinase, transaldolase, transketolase, L-arabinose isomerase, L-ribulokinase, and L-ribulose 5-phosphate 4-epimerase. Expression of the added genes are under the control of Zymomonas mobilis promoters. These newly created microorganisms are useful for fermenting pentoses and glucose, produced by hydrolysis of hemicellulose and cellulose, to produce ethanol.
    Type: Grant
    Filed: April 14, 1995
    Date of Patent: January 27, 1998
    Assignee: Midwest Research Institute
    Inventors: Stephen K. Picataggio, Min Zhang, Christina K. Eddy, Kristine A. Deanda, Mark Finkelstein, Ali Mohagheghi, Mildred M. Newman, James D. McMillan
  • Patent number: 5708735
    Abstract: A fiber-optic device for sensing the presence of a gas in an environment is provided. The device comprises a light source for directing a light beam to a layer system having a first surface and a second surface opposite the first surface. The first surface is exposable to the light beam and the second surface is exposable to the environment. A first light portion encounters and reflects from the first surface at an angle of incidence free from optical wave guide resonance phenomenon and the second light portion encounters and reflects from the first surface at an angle of incidence enabling an optical wave guide resonance phenomenon. The layer system is selected to reversibly react with the gas to be detected. The reaction between the gas and the material changes the material's optical properties and the wavelength at which the optical wave guide resonance occurs.
    Type: Grant
    Filed: March 29, 1996
    Date of Patent: January 13, 1998
    Inventors: David K. Benson, Clemens S. Bechinger, C. Edwin Tracy
  • Patent number: 5705369
    Abstract: The invention relates to the prehydrolysis of lignocellulose by passing an acidic or alkaline solution through solid lignocellulosic particles with removal of soluble components as they are formed. The technique permits a less severe combination of pH, temperature and time than conventional prehydrolysis. Furthermore, greater extraction of both hemicellulose and lignin occurs simultaneously in the same reactor and under the same conditions.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: January 6, 1998
    Assignee: Midwest Research Institute
    Inventors: Robert W. Torget, Kiran L. Kadam, Teh-An Hsu, George P. Philippidis, Charles E. Wyman
  • Patent number: 5692491
    Abstract: An unglazed transpired solar collector using solar radiation to heat incoming air for distribution, comprising an unglazed absorber formed of low thermal-conductance material having a front surface for receiving the solar radiation and openings in the unglazed absorber for passage of the incoming air such that the incoming air is heated as it passes towards the front surface of the absorber and the heated air passes through the openings in the absorber for distribution.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: December 2, 1997
    Assignee: Midwest Research Institute
    Inventors: Craig B. Christensen, Charles F. Kutscher, Keith M. Gawlik
  • Patent number: 5661670
    Abstract: The present invention is a system and method for simulating the performance of a cooling tower. More precisely, the simulator of the present invention predicts values related to the heat and mass transfer from a liquid (e.g., water) to a gas (e.g., air) when provided with input data related to a cooling tower design. In particular, the simulator accepts input data regarding: (a) cooling tower site environmental characteristics; (b) cooling tower operational characteristics; and (c) geometric characteristics of the packing used to increase the surface area within the cooling tower upon which the heat and mass transfer interactions occur. In providing such performance predictions, the simulator performs computations related to the physics of heat and mass transfer within the packing.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: August 26, 1997
    Assignee: Midwest Research Institute
    Inventors: Desikan Bharathan, A. Vahab Hassani
  • Patent number: 5643485
    Abstract: A cooking utensil with improved heat retention includes an inner pot received within an outer pot and separated in a closely spaced-apart relationship to form a volume or chamber therebetween. The chamber is evacuated and sealed with foil leaves at the upper edges of the inner and outer pot. The vacuum created between the inner and outer pot, along with the minimum of thermal contact between the inner and outer pot, and the reduced radiative heat transfer due to low emissivity coatings on the inner and outer pot, provide for a highly insulated cooking utensil. Any combination of a plurality of mechanisms for selectively disabling and re-enabling the insulating properties of the pot are provided within the chamber.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: July 1, 1997
    Assignee: Midwest Research Institute
    Inventors: Thomas F. Potter, David K. Benson, Steven D. Burch
  • Patent number: 5639520
    Abstract: A process for producing a silicon dioxide film on a surface of a silicon substrate. The process comprises illuminating a silicon substrate in a substantially pure oxygen atmosphere with a broad spectrum of visible and infrared light at an optical power density of from about 3 watts/cm.sup.2 to about 6 watts/cm.sup.2 for a time period sufficient to produce a silicon dioxide film on the surface of the silicon substrate. An optimum optical power density is about 4 watts/cm.sup.2 for growth of a 100.ANG.-300.ANG. film at a resultant temperature of about 400.degree. C. Deep level transient spectroscopy analysis detects no measurable impurities introduced into the silicon substrate during silicon oxide production and shows the interface state density at the SiO.sub.2 /Si interface to be very low.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: June 17, 1997
    Assignee: Midwest Research Institute
    Inventor: Bhushan L. Sopori
  • Patent number: 5514584
    Abstract: A process is described for moving fragments that code for cellulase activity from the genome of A. cellulolyticus to several plasmid vectors and the subsequent expression of active cellulase acitivty in E. coli.
    Type: Grant
    Filed: June 27, 1994
    Date of Patent: May 7, 1996
    Assignee: Midwest Research Institute
    Inventors: Stanley M. Lastick, deceased, Melvin P. Tucker, Karel Grohmann
  • Patent number: 5444260
    Abstract: A method for selecting and removing single specific atoms from a solid material surface uses photon biasing to break down bonds that hold the selected atom in the lattice and to reduce barrier effects that hold the atom from transferring to a probe. The photon bias is preferably light or other electromagnetic radiation with a wavelength and frequency that approximately matches the wave function of the target atom species to be removed to induce high energy, selective thermionic-like vibration. An electric field potential is then applied between the probe and the surface of the solid material to pull the atom out of the lattice and to transfer the atom to the probe. Different extrinsic atoms can be installed in the lattice sites that are vacated by the removed atoms by using a photon bias that resonates the extrinsic atom species, reversing polarity of the electric field, and blowing gas comprising the extrinsic atoms through a hollow catheter probe.
    Type: Grant
    Filed: July 1, 1993
    Date of Patent: August 22, 1995
    Assignee: Midwest Reasearch Institute
    Inventor: Lawrence L. Kazmerski
  • Patent number: 5406367
    Abstract: Apparatus for detecting and mapping defects in the surfaces of polycrystalline materials in a manner that distinguishes dislocation pits from grain boundaries includes a laser for illuminating a wide spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface.
    Type: Grant
    Filed: May 10, 1993
    Date of Patent: April 11, 1995
    Assignee: Midwest Research Institute
    Inventor: Bhushan L. Sopori
  • Patent number: 5391896
    Abstract: A single-crystal, monolithic, tandem, multi-color optical transceiver device is described, including (a) an InP substrate having upper and lower surfaces, (b) a first junction on the upper surface of the InP substrate, (c) a second junction on the first junction. The first junction is preferably GaInAsP of defined composition, and the second junction is preferably InP. The two junctions are lattice matched. The second junction has a larger energy band gap than the first junction. Additional junctions having successively larger energy band gaps may be included. The device is capable of simultaneous and distinct multi-color emission and detection over a single optical fiber.
    Type: Grant
    Filed: September 2, 1992
    Date of Patent: February 21, 1995
    Assignee: Midwest Research Institute
    Inventor: Mark W. Wanlass