Patents Assigned to The Harshaw Chemical Company
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Patent number: 5065031Abstract: A personnel dosimetry method and system wherein the identity of a radiation field mixture is determined by using the correlation between two ratios of the responses of two pairs of three TL elements that are filtered to respond differently to the mixed radiation field. Also described is a calibration methodology which links the response of a dosimeter to a variety of different radiation fields calibrated by a standardization agency to the response of the dosimeter to a local and uncalibrated reference source by definition of a local reference of generic unit.Type: GrantFiled: September 10, 1990Date of Patent: November 12, 1991Assignee: The Harshaw Chemical CompanyInventor: Marko Moscovitch
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Patent number: 4975589Abstract: An improved dosimeter characterized by a filter construction which gives rise to improved angular independence of delivered dose. Also disclosed is an improved tamper-proof holder for a TLD card, and the holder also desirably provides a dirt and moisture resistant environment for the TLD card.Type: GrantFiled: July 22, 1988Date of Patent: December 4, 1990Assignee: The Harshaw Chemical CompanyInventors: James D. Chamberlain, Marko Moscovitch
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Patent number: 4957895Abstract: A hydrotreating catalyst is described which comprises at least one Group VI metal, metal oxide, or metal sulfide, and at least one Group VIII metal, metal oxide, or metal sulfide, supported on a carrier wherein (A) the catalyst comprises from about 10% to about 35% by weight of combined metal, and the atomic ratio of the Group VIII metal to Group VI metal is in the range of from about 0.5:1 to about 2:1; (B) the carrier comprises from about 0.5 to about 10 weight percent of halogen, from about 0.5 to about 5% by weight of silica and from about 85 to about 99% of alumina; and (C) the catalyst is characterized as having a median pore radius of from about 30 to about 65 Angstroms, and a surface area of from about 120 to about 180 m.sup.2 /g. Also described are novel and improved procedures for preparing the carrier or support used to prepare the catalysts.Type: GrantFiled: May 23, 1988Date of Patent: September 18, 1990Assignee: The Harshaw Chemical CompanyInventors: Eugene Nebesh, Robert A. Plundo, Steven L. McMahon
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Patent number: 4880495Abstract: This invention relates to a copper etching process which involves contacting the copper with an aqueous etching solution comprising sulfuric acid and a peroxide to which is added less than about 0.2% of an organic additive useful as a crystallization control agent and selected from the group consisting of a low molecular weight glycol and gum arabic. With this compound present, copper sulfate crystals do not adhere to the tank and removal of the crystals from the bath is facilitated.Type: GrantFiled: April 13, 1987Date of Patent: November 14, 1989Assignee: The Harshaw Chemical CompanyInventors: Kestutis F. Petraitis, Walter W. Baldauf, Jr.
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Patent number: 4835388Abstract: A thermoluminescence dosimetry (TLD) card reader includes at least one light detector for detecting light emitted by a heated thermoluminescent element and a heater for heating each TL element. The heater includes a conduit for channeling a flow of gas from a gas source and for discharging heated gas against a TL element, along with means for heating the conduit for transferring heat from it to the gas flowing through it. Preferably, the conduit is electrically conducting and an electrical current is passed through it via leads joined to the conduit near its inlet and outlet ends to heat the tube. A thermocouple disposed proximate the outlet end of the conduit for measuring the temperature of the gas being discharged from the tube, provides an electrical signal to a controllable electrical current source connected to the leads so that the temperature of the gas being discharged from the conduit may be controlled according to a prescribed relationship.Type: GrantFiled: April 7, 1987Date of Patent: May 30, 1989Assignee: The Harshaw Chemical CompanyInventors: William Bruml, Marko Moscovitch, Andras Szalanczy
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Patent number: 4827132Abstract: A novel apparatus and fully automatic, computer implemented method for making radiation dose measurements using composite glow curve data obtained with a thermoluminescent dosimetry reader wherein such composite glow curve data is composed of the superposition of plural overlapping glow peaks plus instrumental and dosimeter background. The background component of the composite glow curve is subtracted out by using an automatic peak search technique followed by individual chip background subtraction based upon the extrapolation of the background curve under the glow curve by fitting on both sides of the curve outside the region of the peaks. Following background subtraction and automatic identification of low temperature signal limits, the leading edges of higher temperature dosimetric peaks are extrapolated to lower temperatures to subtract from the glow curve a lower temperature dosimetric peak without affecting the higher temperature dosimetric peaks.Type: GrantFiled: October 30, 1986Date of Patent: May 2, 1989Assignee: The Harshaw Chemical CompanyInventor: Marko Moscovitch
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Patent number: 4827131Abstract: A novel apparatus and fully automatic, computer implemented method for making radiation dose measurements using composite glow curve data obtained with a thermoluminescent dosimetry reader wherein such composite glow curve data is composed of the superposition of plural overlapping glow peaks plus instrumental and dosimeter background. The background component of the composite glow curve is subtracted out by using an automatic peak search technique followed by individual chip background subtraction based upon the extrapolation of the background curve under the glow curve by fitting on both sides of the curve outside the region of the peaks. Following background subtraction and automatic identification of low temperature signal limits, the leading edges of higher temperature dosimetric peaks are extrapolated to lower temperatures to subtract from the glow curve a lower temperature dosimetric peak without affecting the higher temperature dosimetric peaks.Type: GrantFiled: July 21, 1988Date of Patent: May 2, 1989Assignee: The Harshaw Chemical CompanyInventor: Marko Moscovitch
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Patent number: 4825077Abstract: A system and related method for sensing a parameter of a medium by means of radiation attenuation, the system including a radiation source for emitting radiation that will be attenuated as a function of the parameter upon passage through the medium and a radiation detector operatively positioned to detect the radiation that will be attenuated as aforesaid, and the system being further characterized by the detector comprising a scintillator probe for producing an electrical current output proportionally representative of detected radiation, a current integrator for continuously integrating the electrical current output of the scintillator probe, the current integrator having an input for receiving the electrical current output of the scintillator probe and an output for producing an electrical output representative of the integral of curernt received at the input thereof, a charge injector for supplying to the input of the current integrator current pulses of predetermined total charge and of opposite polarityType: GrantFiled: November 16, 1987Date of Patent: April 25, 1989Assignee: The Harshaw Chemical CompanyInventors: Riad A. Tawil, David H. Sicking
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Patent number: 4422774Abstract: A barrel loading and unloading station that includes a barrel support stand 10 for supporting a plating barrel 18 in predetermined positions and a door handling apparatus 14 for releasing and separating a barrel access door 16 from the plating barrel. The door handling apparatus 14 includes a door assembly 40 mounted for reciprocating motion towards and away from the plating barrel by a pair of trackways 42 that are mounted to an elevator mechanism 44 that is operative to raise and lower the trackways to increase accessibility to the barrel after the access door has been removed. One embodiment of the door handling assembly 40 includes a pair of rotatable spindles 56 operative to engage and rotate locking knobs 220 on the barrel access door 16 and a slide mechanism 120 for unlatching the door from the barrel. Another embodiment of the door handling assembly 40' includes a plurality of clamp engaging spreader arms 366 operative to spread and release resilient clamps 352 from the plating barrel.Type: GrantFiled: March 20, 1981Date of Patent: December 27, 1983Assignee: The Harshaw Chemical CompanyInventor: Frank Little
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Patent number: 4422817Abstract: A load manipulating apparatus including a turnstile 10 supported for rotation about a fixed stub shaft 30 defining a substantially vertical axis, an elevating mechanism 12 supported for vertical reciprocating motion by the turnstile, and a rotatable operating arm 14 carried by the elevating mechanism including a mechanism 205 for releasably engaging a load receiving container 18. Support columns 22 defining a path of motion for the elevating mechanism include integral fluid reservoirs that form part of a fluid pressure operating system for effecting movements in the turnstile, elevator, operating arm, and container engaging mechanism.Type: GrantFiled: May 29, 1981Date of Patent: December 27, 1983Assignee: The Harshaw Chemical CompanyInventor: Frank Little
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Patent number: 4410468Abstract: A method is disclosed for hot press-forging a normally frangible optically integral crystalline mass ("optical body") in a closed die, by directly pressing a surface of the mass while it is peripherally surrounded by a crystal powder the amount of which is computed from the deformation ratio desired and the geometry of the die. The crystal powder is compacted by the nonuniformly directed forces transmitted to it by the optical body, and eventually the crystal powder is sufficiently dense so as dynamically to constrain the optical body at its peripheral surface. The dynamic constraint of the optical body while it is being forged is effected in such a way as to permit deformation of the optical body without fracturing it, and, without affecting its optical integrity.Type: GrantFiled: July 6, 1981Date of Patent: October 18, 1983Assignee: The Harshaw Chemical CompanyInventor: Herbert Packer
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Patent number: 4405413Abstract: A bright acid zinc plating bath uses a surfactant or wetting agent having the general formula C.sub.n H.sub.2n+1 (OCH.sub.2 CH.sub.2).sub.x OCH.sub.2 COOH wherein n is either 8 or 9, and wherein between 30 and 70% of the surfactant contains between 17 and about 21 ethylene oxide groups and 70-30% contains between about 9 and about 12 ethylene oxide groups. When used with organic brighteners, the blend of surfactants permits the electrodeposition of a bright layer which resists the formation of haze or blush which can occur when a plated part is flexed or is subjected to elevated temperatures encountered, e.g., upon curing of a protective lacquer coating.Type: GrantFiled: May 20, 1982Date of Patent: September 20, 1983Assignee: The Harshaw Chemical CompanyInventor: Carol W. Skimin
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Patent number: 4401542Abstract: A metal finishing barrel having a body section 10 extending between a pair of end caps 12, that includes a sidewall comprising a plurality of wall sections 14, 16 joined edge-to-edge. In one embodiment, the wall sections are formed from a single, continuous sheet member 44, bent along lines of weakness in the form of V-shaped notches 46 that each define a relatively thin, hinge-like bridging section 46a that connects adjacent wall sections. External locking ribs 50 coengage edge portions of adjacent wall sections to maintain the sheet member in its assembled configuration. Alternately, individual wall panels 14', 16' are fabricated with beveled edge surfaces 46' and are secured in edge confronting engagement by the external locking ribs. In an alternate embodiment, an internal locking rib is employed that also serves as a tumbling rib and coengages locking grooves formed on inside surfaces of edge portions of each wall section.Type: GrantFiled: May 28, 1981Date of Patent: August 30, 1983Assignee: The Harshaw Chemical CompanyInventors: Frank P. Zamiska, Norman B. Tipton
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Patent number: 4360431Abstract: A self-unloading centrifuge for use in a metal finishing process which comprises a drum 10 having a perforate cylindrical sidewall 10a, supported for rotation about a vertical axis by a support base 19 and a driving arrangement 12 for rotating the drum. A tilt mechanism 36 is operative to engage and rotate the drum about a substantially transverse axis, spaced laterally from the center axis of the drum in order to discharge the processed parts. Clamping devices 30 are operative to decouple the drum from its driving arrangement prior to unloading and are operative to recouple the drum after reloading. Top and side covers 140, 120, 122, 126 enclose the drum when in its operating position and open as the drum moves to its unloading and/or loading position.Type: GrantFiled: May 1, 1981Date of Patent: November 23, 1982Assignee: The Harshaw Chemical CompanyInventor: Frank Little
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Patent number: 4360450Abstract: A process for improving the flame-retardant properties of cellulose containing fibrous materials in the absence of halogen compounds which comprises treating said fibrous materials with an effective amount of a colloidal aqueous dispersion of an alkali metal polyantimonate containing a mole ratio of alkali metal to antimony in the dispersion of at least about 0.3:1, and drying said materials is described.Type: GrantFiled: November 25, 1981Date of Patent: November 23, 1982Assignee: The Harshaw Chemical CompanyInventor: Destin A. LeBlanc
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Patent number: 4359661Abstract: A highly sensitive Geiger-Mueller radiation detector with improved temperature stability and working life uses a cathode liner made of tungsten. The liner is resistant to attack by the halogen quench gases which are used in the detector. The method of conditioning the tube for use is much simpler and less expensive than it is for existing tubes.Type: GrantFiled: August 29, 1980Date of Patent: November 16, 1982Assignee: The Harshaw Chemical CompanyInventor: Nicolas Mitrofanov
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Patent number: 4354135Abstract: A highly sensitive Geiger-Mueller radiation detector with improved temperature stability and working life uses a cylindrical cathode made from a nickel copper alloy preferably containing predominantly nickel. This alloy is resistant to attack by halogen quench gases used in the tube and provides an excellent surface for the electrodeposition of platinum to provide a low porosity surface.Type: GrantFiled: May 14, 1980Date of Patent: October 12, 1982Assignee: The Harshaw Chemical CompanyInventors: Nicholas Mitrofanov, Arthur C. Lucas
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Patent number: 4351741Abstract: A method of preparing antimony pentoxide from solids containing antimony sulfides is described. The method comprises the steps of(a) leaching the antimony values from the solids with an aqueous potassium hydroxide solution to form an antimony-containing solution and a gangue,(b) oxidizing the antimony present in the leaching solution to a pentavalent antimony,(c) recovering the oxidized solution, and(d) adding an inorganic acid to the solution to reduce the pH of the solution to about 5-7 whereby antimony pentoxide is precipitated from the solution. The gangue may be separated from the leach solution either prior to or after the oxidizing step.In a preferred embodiment, the oxidation of the solution is conducted in the presence of a catalyst which comprises a water-soluble copper salt, a quinone, a hydroquinone or mixtures of one or more of these.Type: GrantFiled: February 5, 1979Date of Patent: September 28, 1982Assignee: The Harshaw Chemical CompanyInventor: John W. Vogt
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Patent number: 4341654Abstract: The addition of a getter consisting essentially of reactive oxides of boron and silicon, to a melt of an alkali metal halide serves to overcome problems of unacceptable color, afterglow and hardness attributable to trace impurities present in the melt. These trace impurities are generally metals present in a concentration less than 1 part per million (ppm) parts of melt. An ingot melt-grown from charge stock treated with the getter provides high quality optical bodies such as light pipes, laser windows and scintillators. Specific problems characteristic of a scintillator ingot grown from a highly purified alkali metal halide "remelt", such as is obtained by crushing and melting portions of a melt-grown ingot, are overcome by adding to the remelt a portion of fresh powder stock in which the getter has been uniformly distributed.Type: GrantFiled: March 9, 1981Date of Patent: July 27, 1982Assignee: The Harshaw Chemical CompanyInventor: Carl F. Swinehart
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Patent number: 4341655Abstract: A method of preparing colloidal sols of pentavalent antimony containing increased amounts of metal is described. More particularly, a method of converting substantially water-insoluble metal antimonates to colloidal sols of pentavalent antimony is described. The method comprises mixing a substantially water-insoluble metal antimonate with a pentavalent antimony sol and agitating the mixture for a period of time sufficient to convert at least a portion of the crystalline metal antimonate to the colloidal state. The colloidal sols obtained in the described manner contain an increased amount of the metal, and such sols are useful as flame-retardants.Type: GrantFiled: March 28, 1980Date of Patent: July 27, 1982Assignee: The Harshaw Chemical CompanyInventor: John G. Richardson