Patents Represented by Attorney John A. Crowley, Jr.
  • Patent number: 4083925
    Abstract: Sufficient anionic polyacrylamide having molecular weight of at least 2,800,000 is contacted with alkali metal aluminate liquor containing ferrous iron until a substantial proportion of the ferrous iron is precipitated, and said precipitate and liquor are separated. The process is particularly useful as an improvement in the Bayer process for preparing alumina from bauxite.
    Type: Grant
    Filed: March 22, 1976
    Date of Patent: April 11, 1978
    Assignee: Martin Marietta Aluminum, Inc.
    Inventors: John A. S. Green, Sergio A. Loynaz
  • Patent number: 4076498
    Abstract: Polyethylene textile fibers dyed with the dyestuff resulting from coupling equimolar amounts of diazotized ##STR1## and the coupling components obtained by reacting 3-amino-4-methoxyacetanilide or 3-amino-4-ethoxyacetanilide with diethyl sulfate, wherein X is Cl or Br are disclosed. Said fibers are a desirable greenish blue shade, with good fastness properties, and a very green flare under incandescent light.
    Type: Grant
    Filed: September 20, 1976
    Date of Patent: February 28, 1978
    Assignee: Martin Marietta Corporation
    Inventor: Laszlo A. Meszaros
  • Patent number: 4035469
    Abstract: A process for removing boron contaminant from magnesium halide-containing brine wherein the brine is contacted with active magnesia to precipitate boron-containing magnesium hydrate and to remove at least 50%, and up to at least 95%, by weight of the total boron content of the untreated brine, without reduction of the magnesium halide content of said brine. The active magnesia is employed in an amount of from about 0.1% to about 10% by weight, preferably from about 2% to about 6% by weight, of the untreated brine, which may be heated e.g., from about 140.degree. F to the boiling point thereof, prior to contact with said active magnesia. Subsequently, the treated brine can be used, by reacting it with dolime, to form magnesium hydroxide which, in turn, can be calcined to produce MgO, each of which is a high-purity-low-boron product, i.e., less than 150 ppm boron on an oxide basis, and preferably less than 75 ppm. In addition, the MgO will contain less than 1.
    Type: Grant
    Filed: December 5, 1975
    Date of Patent: July 12, 1977
    Assignee: Martin Marietta Corporation
    Inventors: Alvin Richmond, John Francis Bent
  • Patent number: 4019918
    Abstract: High strength Portland cement compositions comprised of Portland cement clinker which has been ground to a specific surface area of between about 4400 cm.sup.2 /g and up to 6000 cm.sup.2 /g, alkali or alkaline earth lignosulfonate in an amount of between about 0.75 and 1.25 percent by weight, sodium bicarbonate in an amount of between about 1.25 and 2.5 percent by weight, and gypsum in an amount of between about 1.5 and 4.0 percent by weight, wherein the lignosulfonate and the bicarbonate are present in a ratio of about one to two and the cement product formed has a porosity of less than about 5 percent by volume voids. The cement compositions have an adequate plastic period of from at least about 90 minutes, as well as adequate and/or improved one and twenty-eight day strengths of in excess of about 5000 psi and 6000 psi, respectively. Sand or sand, crushed rock and/or gravel can be incorporated into the cement mixes or compositions to form mortar and concrete products.
    Type: Grant
    Filed: February 2, 1976
    Date of Patent: April 26, 1977
    Assignee: Martin Marietta Corporation
    Inventor: Milton Herman Wills, Jr.
  • Patent number: 3945863
    Abstract: A process for pretreating metal powders for the preparation of dispersion hardened metal alloys whereby an iron, cobalt or nickel base metal powder is homogeneously mixed with a chromium powder and with a prealloyed metal carbide powder and granulated to a powder granulate. The granulate is then classified and reduced to remove oxygen present therein.
    Type: Grant
    Filed: September 20, 1973
    Date of Patent: March 23, 1976
    Assignee: Martin Marietta Corporation
    Inventor: Walter Precht