Abstract: A process is provided to prepare durable, high gloss titanium dioxide pigments by a continuous wet treatment process which involves curing of a silica coating at pH of between 7.0 and 8.5. Pigment prepared in this fashion is substantially free from Al(OH).sub.3 impurities and has excellent performance properties in high quality latex paint formulations.
Type:
Grant
Filed:
July 2, 1998
Date of Patent:
November 30, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Michael P Diebold, Charles Robert Bettler, Phillip Martin Niedenzu, Anhtony John Coombe, John Phillip Lanci, Sr.
Abstract: This invention relates to isolated nucleic acid fragments encoding all or a substantial portion of a corn 4-.alpha.-glucanotransferase. The invention also relates to the construction of chimeric genes encoding all or a portion of a corn 4-.alpha.-glucanotransferase, in sense or antisense orientation, wherein expression of the chimeric gene results in production of altered levels of corn 4-.alpha.-glucanotransferase in a transformed host cell.
Abstract: An endoscope contains no adhesives, epoxies, or other organic materials. The endoscope includes a set of lenses held in position by cylindrical spacers. A pair of windows seal the ends of the endoscope, and prevent the lenses and spacers from falling out. The windows are brazed to the endoscope. Due to the use of brazing, no adhesives are needed to hold the lenses or windows in place. Thus, one can sterilize the endoscope in the high temperature environment of an autoclave, without risking damage to the optical components. The brazing produces a hermetic seal which enables the endoscope to function properly in an environment of high temperature or high pressure, or in chemically abusive environments.
Type:
Grant
Filed:
December 19, 1997
Date of Patent:
November 30, 1999
Assignee:
Three E Laboratories, Inc.
Inventors:
Michael J. Pollack, Guy M. Atkinson, Eugene J. Kelly
Abstract: A process is disclosed for preparing an adduct of the formula R.sup.1 CF.sub.2 CH.sub.2 OCF.sub.3-a-m (C.sub.2 H.sub.n X.sub.4-n F).sub.m R.sup.2.sub.a wherein R.sup.1 is selected from the group consisting of --(CF.sub.2).sub.p H and --C.sub.p F.sub.2p+1 where p is 0 or an integer from 1 to 6; R.sup.2 is selected from the group consisting of --H, --CHF.sub.2, --CHFCF.sub.3, --CHFOCF.sub.3, --CHFO(CF.sub.2).sub.2 CF.sub.3, and --CHClF; each X is independently selected from the group consisting of Br, Cl and F; a is 0 or 1; m is 1 or 2, provided that when a is 1 and R.sup.2 is other than hydrogen, then m is 1; and n is 0, 1 or 2. The process involves reacting a fluorinated ether of the formula R.sup.1 CF.sub.2 CH.sub.2 OCF.sub.3-a R.sup.2.sub.a with an olefin of the formula C.sub.2 H.sub.n X.sub.4-n in the liquid phase in the presence of antimony pentafluoride catalyst. Also disclosed is a process for preparing unsaturated ethers of the formula R.sup.1 CF.sub.2 CH.sub.2 OCF.sub.3-a-m (C.sub.2 H.sub.n X.sub.
Abstract: Magnetorheological liquids, a process for producing them, their use and a process for producing polymer-coated magnetisable particles used in the magnetorheological liquids.
Type:
Grant
Filed:
November 24, 1997
Date of Patent:
November 23, 1999
Assignee:
G E Bayer Silicones GmbH & Co. KG
Inventors:
Wolfgang Podszun, Olaf Halle, Johan Kijlstra, Robert Bloodworth, Eckhard Wendt
Abstract: Disclosed herein is a novel physical form of low molecular weight poly(trimethylene terephthalate). This form may be produced from molten low molecular weight poly(trimethylene terephthalate) material by means of rapid heat transfer from the material. The poly(trimethylene terephthalate) composition is suitable for use as a starting material for solid-state polymerization in order to produce polymers of higher molecular weight.
Type:
Grant
Filed:
June 22, 1998
Date of Patent:
November 23, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Elwood Neal Blanchard, Craig Robert Gochanour, Kenneth Wayne Leffew, Jan M. Stouffer
Abstract: An active single-mode optical fiber has the core made of a rare earth doped non-oxide glass and the cladding made of an oxide glass. The glass of the core has a melting temperature lower than that of the glass of the cladding and lying within the range of the softening temperatures of the latter. In a preferred embodiment the core is made of a chalcogenide glass and the cladding is made of a lead silicate glass. To produce the fiber, a preform, obtained by introducing an element made of the non-oxide glass into the hole of a capillary tube made of the oxide glass, is brought to a temperature lying within the range of softening temperatures of the oxide glass and not lower than the melting temperature of the non-oxide glass, and is drawn. The capillary tube, during the drawing process, serves as a container for the molten glass of the core.
Type:
Grant
Filed:
October 31, 1997
Date of Patent:
November 23, 1999
Assignee:
Cselt- Centro Studi E Laboratori Telecomunicazioni S.p.A.
Abstract: A method and apparatus are disclosed for externally and noninvasively determining the temperatures of chemical reactions inside a plurality of separate closed vessels that are made of materials that substantially transparent to microwave radiation but that are poor conductors of heat. The method comprises exposing a plurality of substantially microwave-transparent of vessels containing chemical reagents therein to microwave radiation, concurrently measuring the temperature of the reagents inside a first vessel using a first temperature sensor inside the first vessel and while measuring the temperature of the exterior of the first vessel using a second temperature sensor positioned externally to the first vessel, and immediately thereafter successively measuring the temperature of the exterior of the remainder of the vessels using the second sensor.
Type:
Grant
Filed:
September 15, 1997
Date of Patent:
November 23, 1999
Assignee:
C E M Corporation
Inventors:
Todd Mark Hochrad, William Edward Jennings, Edward Earl King
Abstract: The present invention provides a process for the preparation of N-[2,4-dichloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4- triazol-1-yl]phenyl]methanesulfonamide (I) which comprises reacting 2-(5-amino-2,4-dichlorophenyl)-4-(difluoromethyl)-2,4-dihydro-5-methyl-3H- 1,2,4-triazol-3-one (II) with methanesulfonyl chloride in the presence of a catalytic amount of a source of soluble halide.
Abstract: A seal ring for placement in the space between a radial groove of a cylindrical member and a housing forming a bore in which the cylindrical member is movably positioned, which is free of scoring and has a fracture line through its thickness to form opposing faces. The faces are rough and mesh together such that when the faces are forced into contact, the faces are then interlocked. Furthermore, the seal ring has true roundness to enable the seal ring to seal the space despite presence of the fracture line. The seal ring is made up of a rigid polymer such as a polyimide, polyamide, polyester, polyetheretherketone, polyamideimide, polyetherimide, polyphenylene sulfide, and polybenzimidazole. The seal ring of the present invention is capable of single ring sealing of the space between the bore and the radial groove. The present invention also provides a device for fracturing the seal ring.
Type:
Grant
Filed:
May 1, 1997
Date of Patent:
November 23, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Richard Gerard Van Ryper, James Ronald Mott, Arnold Wayne Raymond, Christopher Scott Stenta
Abstract: Poly(ester-ethers) are produced by the copolymerization of tetrahydrofurans and cyclic carboxylic anhydrides using selected metal perfluoroalkylsulfonates and related compounds as catalysts. The resulting copolymers are useful as intermediates for monomers for use in other polymerizations.
Abstract: Flame resistant polyester resin composition comprising a polyester matrix resin containing a polyalkylene oxide, a brominated flame retardant, and a brominated dialkyl phthalate which exhibits low melt viscosity, excellent flow, improved welding strength and resistance to thermal shock.
Abstract: A process for selectively hydrogenating a dinitrile to an aminonitrile is provided. The process comprises contacting a dinitrile with a hydrogen-containing fluid in the presence of a solvent comprising an alcohol or liquid ammonia, at least one metal catalyst, and a carbonyl group-containing additive such as, for example, organic amides, organic esters, salts of carboxylic acids or urea.
Type:
Grant
Filed:
March 15, 1999
Date of Patent:
November 16, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Alex Sergey Ionkin, Stanislaw Bogdan Ziemecki, Mark Jay Harper, Theodore Augur Koch
Abstract: A gun cleaning accessory for use with a gun cleaning rod and jag to safely and effectively retain the cleaning patch on the cleaning rod jag during cleaning and the method of using such device. The invention is installed on the muzzle end of a gun barrel and the cleaning rod inserted at the breech end. The invention has two body portions that hingedly surround the gun barrel muzzle and are held in position with a temporary fastener. The invention further has a front closure wall that is positioned in front of the gun muzzle to restrict the lengthwise motion of the cleaning rod. Using the muzzle jag stop during cleaning protects the gun cleaner from injury due to jamming or slipping of the cleaning and stopping devices and also from the accidental firing of the gun. The method of using the muzzle jag stop during cleaning also protects the gun from damage and wear due to slipping, marring, and repeated impact against the barrel of the stopping device.
Abstract: Improved hydrogenation catalysts consisting essentially of reduced or at least partially reduced ruthenium and tin on a refractory oxide support which is insoluble in aqueous acid. Such catalysts are very durable and exhibit high conversion rates in aqueous acidic solution hydrogenation of hydrogenatable precursors (e.g. maleic acid, succinic acid, gamma-butyrolactone etc.) and high selectivity for their conversion to 1,4-butanediol and gamma-butyrolactone and their mixtures.
Type:
Grant
Filed:
March 27, 1997
Date of Patent:
November 16, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Patricia Ann Tooley, Jesse Raymond Black
Abstract: The method of making a semiconductor body from a semiconductor polymeric compound containing about 20% by weight lampblack having a porous structure, about 60% by weight of low density polyethylene, about 8.5% by weight ethylene vinyl acetate copolymer, about 4.0% by weight calcium stearate, about 3.0% by weight antioxidant and about 0.5% by weight calcium titanate includes the steps of extruding the semiconductor polymeric compound to form an extruded product and subsequently calendering the extruded product to produce a semiconductor body having an electrical conductivity which is as uniform as possible throughout the entire bulk of the semiconductor body.
Type:
Grant
Filed:
May 22, 1998
Date of Patent:
November 16, 1999
Assignee:
Metagal Industria E Comercio LTDA
Inventors:
Humberto Takashi Kadooka, Ricardo Proveda Moreno, Olavo Nunes Da Costa
Abstract: Semiconductor structure for a transistor, having at least one doped crystalline semiconductor layer (3) consisting of a semiconductor material such as silicon or germanium which is applied onto a further crystalline layer, wherein the doped semiconductor layer (3) contains carbon alloyed with this semiconductor material to improve the conduction characteristics, and wherein a desired strain can be set in the active semiconductor layer (3) via the proportion of carbon relation to the semiconductor material.
Type:
Grant
Filed:
September 6, 1996
Date of Patent:
November 16, 1999
Assignee:
Max-Planck-Gesellschaft zur Foerderung der Wissenschaften e. V.
Abstract: Peptide nucleic acids and analogues of peptide nucleic acids are used to form duplex, triplex, and other structures with nucleic acids and to modify nucleic acids. The peptide nucleic acids and analogues thereof also are used to modulate protein activity through, for example, transcription arrest, transcription initiation, and site specific cleavage of nucleic acids.
Type:
Grant
Filed:
June 7, 1995
Date of Patent:
November 16, 1999
Assignees:
Isis Pharmaceuticals, Inc., Peter E. Nielsen
Inventors:
David J. Ecker, Ole Buchardt, Michael Egholm, Peter E. Nielsen, Rolf H. Berg, Niels E. Mollegaard