Patents Represented by Attorney I. L. Ericson
  • Patent number: 5538533
    Abstract: An improved ceramic composite comprising oxide ceramic particulates, nonoxide ceramic particulates selected from the group consisting of carbides, borides, nitrides of silicon and transition metals and mixtures thereof, and a ductile binder selected from the group consisting of metallic, intermetallic alloys and mixtures thereof is described. The ceramic composite is made by blending powders of the ceramic particulates and the ductile to form a mixture and consolidating the mixture of under conditions of temperature and pressure sufficient to produce a densified ceramic composite.
    Type: Grant
    Filed: September 11, 1995
    Date of Patent: July 23, 1996
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Kathleen B. Alexander, Terry N. Tiegs, Paul F. Becher, Shirley B. Waters
  • Patent number: 5536292
    Abstract: Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering.
    Type: Grant
    Filed: August 22, 1995
    Date of Patent: July 16, 1996
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Cressie E. Holcombe, Norman L. Dykes, Marvin S. Morrow
  • Patent number: 5496522
    Abstract: The present invention relates to chemical sensor and biosensor probes for measuring low concentration of metals and metal ions in complex samples such as biological fluids, living cells, and environmental samples. More particularly the present invention relates to a gel-based Indo-1 and Fura-2 chemical sensor probes for the measurement of low concentrations of calcium, cadmium, magnesium and the like. Also disclosed is a detector device using the sensors of the present invention.
    Type: Grant
    Filed: February 7, 1994
    Date of Patent: March 5, 1996
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Tuan Vo-Dinh, Pierre Viallet
  • Patent number: 5494811
    Abstract: A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves.
    Type: Grant
    Filed: January 26, 1995
    Date of Patent: February 27, 1996
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Charles D. Scott, Joseph A. Marasco
  • Patent number: 5017528
    Abstract: Silicon carbide whisker-reinforced ceramic composites are fabricated in a highly reproducible manner by beneficating the surfaces of the silicon carbide whiskers prior to their usage in the ceramic composites. The silicon carbide whiskers which contain considerable concentrations of surface oxides and other impurities which interact with the ceramic composite material to form a chemical bond are significantly reduced so that only a relatively weak chemical bond is formed between the whisker and the ceramic material. Thus, when the whiskers interact with a crack propagating into the composite the crack is diverted or deflected along the whisker-matrix interface due to the weak chemical bonding so as to deter the crack propagation through the composite. The depletion of the oxygen-containing compounds and other impurities on the whisker surfaces and near surface region is effected by heat treating the whiskers in a suitable oxygen sparaging atmosphere at elevated temperatures.
    Type: Grant
    Filed: November 30, 1989
    Date of Patent: May 21, 1991
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Terry N. Tiegs, Terrence B. Lindemer