With Catalyst Or Accelerator Patents (Class 436/159)
  • Patent number: 6375900
    Abstract: A carbon analyzer, is provided which includes a combustion chamber having a platinum on titania catalyst. The combustion chamber and catalyst are also provided. A method for analyzing carbon-containing specimens with such an analyzer is also provided as well as a method for oxidizing such specimens with a platinum on titania catalyst. A method of conditioning the catalyst is also provided.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: April 23, 2002
    Assignee: Tekmar Company
    Inventors: Maria Theresa Lee-Alvarez, Robert A. Booth
  • Patent number: 6368865
    Abstract: A combinatorial process for simultaneously conducting multiple catalytic chemical reactions in parallel has been developed. At least one catalyst is contained in the reaction zones of a plurality of reactors, each reactor having a reactor insert placed within a sleeve and inserted into a well, the reaction zone of each reactor being formed between a fluid permeable structure attached to the sleeve and a fluid permeable end of the corresponding reactor insert. A fluid reactant is flowed through each reactor where it is contacted with the catalyst contained in the reaction zone to form an effluent. The effluents are removed from the effluent from the reactor and are analyzed.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: April 9, 2002
    Assignee: UOP LLC
    Inventors: Ivar M. Dahl, Arne Karlsson, Duncan E. Akporiaye, Rune Wendelbo, Kurt M. Vanden Bussche, Gavin P. Towler
  • Patent number: 6333196
    Abstract: Apparatus for testing catalyst candidates including a multicell holder e.g. a honeycomb or plate, or a collection of individual support particles that have been treated with solutions/suspensions of catalyst ingredients to produce cells, spots or pellets holding each of a variety of combinations of the ingredients and dried, calcined or treated as necessary to stabilize the ingredients in the cells, spots or pellets. The apparatus also includes structure for contacting the catalyst candidates with a potentially reactive feed stream or batch e.g., biochemical, gas oil, hydrogen plus oxygen, propylene plus oxygen, CCl2F2 and hydrogen, etc. The reaction occurring in each cell can be measured, e.g. by infrared thermography, spectroscopic detection of products or residual reactants, or by sampling, e.g. by multistreaming through low volume tubing, from the vicinity of each combination, followed by analysis e.g.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: December 25, 2001
    Assignee: University of Houston
    Inventor: Richard C. Willson, III
  • Publication number: 20010036670
    Abstract: An apparatus for monitoring the concentration of an oxidative gas or vapor includes a chemical substance which reacts with the oxidative gas or vapor to produce a heat change. A temperature probe is coupled to the chemical substance and adapted to respond to the heat change. The temperature probe can be coupled to the chemical substance by a carrier, and can include a reference temperature probe. Additionally, a method of using the apparatus is described, as well as a sterilization system which utilizes the apparatus.
    Type: Application
    Filed: December 19, 2000
    Publication date: November 1, 2001
    Inventors: Ben Fryer, Debra Timm, Szu-Min Lin, Henry Hui, Sam Nutt
  • Patent number: 6306658
    Abstract: An apparatus and method for carrying out and monitoring the progress and properties of multiple reactions is disclosed. The method and apparatus are especially useful for synthesizing, screening, and characterizing combinatorial libraries, but also offer significant advantages over conventional experimental reactors as well. The apparatus generally includes multiple vessels for containing reaction mixtures, and systems for controlling the stirring rate and temperature of individual reaction mixtures or groups of reaction mixtures. In addition, the apparatus may include provisions for independently controlling pressure in each vessel, and a system for injecting liquids into the vessels at a pressure different than ambient pressure. In situ monitoring of individual reaction mixtures provides feedback for process controllers, and also provides data for determining reaction rates, product yields, and various properties of the reaction products, including viscosity and molecular weight.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: October 23, 2001
    Assignee: Symyx Technologies
    Inventors: Howard W. Turner, G. Cameron Dales, Lynn VanErden, Johannes A. M. van Beek
  • Patent number: 6306349
    Abstract: The present invention relates to a catalyst characterization apparatus, and in particular to an improved catalyst characterization apparatus which is capable of characterizing the surface of a catalyst more accurately by a volumetric method without requiring a pre-treatment step which may vary the characteristics of the catalyst as well as without exposing the catalyst in air, by combining a dynamic flow type reactor with a volumetric type adsorption apparatus, whereby it is possible to accurately characterize the catalyst during an actual reaction. It is possible to accurately characterize the various catalysts and to characterize the catalyst during the reaction, alternately and/or continuously, by combining a dynamic flow type reactor with a volumetric type characterization apparatus as well as a dynamic flow type characterization apparatus.
    Type: Grant
    Filed: November 29, 1999
    Date of Patent: October 23, 2001
    Assignee: Korea Institute of Science and Technology
    Inventors: Dong Ju Moon, Kun You Park, Moon Jo Chung, Byoung Sung Ahn
  • Publication number: 20010029047
    Abstract: A process for modifying a triacylglycerol stock, such as a vegetable oil stock, to better control fluidity is provided. The process includes interesterifying the triacylglycerol stock in the presence of a basic catalyst while monitoring the absorbance of the reaction mixture. A modified triacylglycerol stock produced by partial interesterification as well as plastic spreads and water-in-oil emulsions which include the partially interesterified triacylglycerol stock are also provided.
    Type: Application
    Filed: March 20, 2001
    Publication date: October 11, 2001
    Applicant: Cargill, Incorporated
    Inventors: Linsen Liu, Daniel Scott Lampert
  • Patent number: 6251685
    Abstract: A method for reading out data from microlocations of a microelectronic array involves activating multiple microlocations in parallel and simultaneously detecting the responses from the activated microlocations to determine concentrations of molecular biological material at each microlocation. In a preferred embodiment, the microelectronic array includes electronically addressable electrodes at each microlocation which can be individually activated via a control system. An electrochemiluminescent detection technique is used to detect the presence and determine the concentration of bound molecular biological material that is located at each microlocation. Electrochemiluminescent material is utilized because it gives off light when excited by an applied electrical field. With an addressable microelectronic array, electrical fields can be applied to various combinations of microlocations simultaneously to allow readout of several microlocations in parallel.
    Type: Grant
    Filed: February 18, 1999
    Date of Patent: June 26, 2001
    Assignee: Agilent Technologies, Inc.
    Inventors: Andreas Nikolaus Dorsel, Mel N. Kronick, Gary B. Gordon
  • Patent number: 6242262
    Abstract: A method for isolating an active catalyst from a library of compounds that are potential catalysts is disclosed. The method involves providing a library which comprises a plurality of discrete solid supports, each solid support having a different organic compound bound thereto; and providing a reaction solution in a reaction vessel, the reaction solution containing the reactant or reactants necessary for a chemical reaction to occur in the presence of a catalyst for that reaction. The library and the reaction solution are then combined in the reaction vessel, and then one of the discrete solid supports is detected that is characterized by a temperature change in said solution greater than the temperature change of a plurality of other of said discrete solid supports in said solution. The detected solid support carries an active catalyst for the chemical reaction. Continuous flow apparatus for carrying out the method is also disclosed.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: June 5, 2001
    Assignee: The University of North Carolina at Chapel Hill
    Inventors: James P. Morken, Steven J. Taylor
  • Patent number: 6160255
    Abstract: A laser-based photoacoustic sensor performs trace detection and differentiation of atmospheric NO and NO.sub.2 in order to obtain respective concentrations for NO and NO.sub.2 using photoacoustic spectroscopy. The device of the invention employs a single, pulsed laser having two outputs near 454 nm and 227 nm, respectively, to irradiate a sample vapor, the sample vapor being collected by a hand-held wand. A photoacoustic response from both NO and NO.sub.2 is detected using microphone detectors, is converted into electrical signals, and is analyzed using a microcomputer. The results of the analysis--the respective concentrations of NO and NO.sub.2 in the sample vapor--are displayed on a digital oscilloscope. Preferably, the electrical signals are amplified prior to analysis, and a boxcar integrator is used to sample and average the electrical signals during the analysis operation.
    Type: Grant
    Filed: October 5, 1998
    Date of Patent: December 12, 2000
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Rosario C. Sausa
  • Patent number: 6146898
    Abstract: An apparatus and method for on-line decomposition of a hydrogen peroxide solution, for use in fabricating a semiconductor device, includes a membrane tube having a porous plug inserted in each end, with the porous plugs defining a space where a platinum catalyst is disposed. A first coupling tube is inserted into one end of the membrane tube to supply a hydrogen peroxide sample to the membrane tube. The hydrogen peroxide contained in hydrogen peroxide sample is decomposed into water and oxygen gas according to an action of the platinum catalyst. A second coupling tube is inserted into a second end of the membrane tube to discharge a diluted hydrogen peroxide solution to an analytical instrument, where the decomposed hydrogen peroxide solution is analyzed on-line.
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: November 14, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung-chul Kang, Dong-soo Lee
  • Patent number: 6133042
    Abstract: A method and apparatus is provided for modulating the flux of oxygen impinging on a calorimetric gas sensor. The method and apparatus are based on modulating the oxygen concentration of a gas mixture presented to the microcalorimeter between a predetermined high level and at a substantially zero value to create a modulated output to reduce the noise of the sensor and to eliminate its zero-offset.
    Type: Grant
    Filed: February 10, 1998
    Date of Patent: October 17, 2000
    Assignee: Ford Global Technologies, Inc.
    Inventors: Margherita Zanini-Fisher, Eleftherios M. Logothetis, Jacobus H. Visser
  • Patent number: 6087181
    Abstract: The present invention discloses a method for improving the speed and sensitivity of optical spectroscopic techniques for remote detection of trace chemical species in a carrier gas. The disclosed method can be applied to any optical spectroscopic detection technique whose sensitivity decreases as the total pressure of the sample decreases. The method employs an inert and non-absorbing buffer gas to supplement the pressure exerted by the carrier gas. This ensures that the total pressure of the sample, and hence sensitivity of the detection technique, remains high. The method is especially useful when measuring concentration of chemical species produced at small rates, and therefore should prove useful for rapid serial screening of combinatorial libraries of compounds.
    Type: Grant
    Filed: March 16, 1998
    Date of Patent: July 11, 2000
    Assignee: Symyx Technologies
    Inventor: Pejun Cong
  • Patent number: 6087180
    Abstract: Apparatus and process for real time analysis of the intermediates and products of a gas phase chemical reaction catalyzed by a particulate catalyst. Real time analysis is conducted under high vacuum using a detection device contained within a high vacuum chamber. The reactor is connected to the vacuum chamber but is outside thereof, allowing the reactor to be operated either at high vacuum or under moderate pressure. Reactors and reactor feed manifolds of varying configuration may be interchangeably connected to the vacuum chamber on an essentially modular basis. Only a single vacuum system is required for the apparatus. Reaction products may also be analyzed by methods such as gas chromatography. Simultaneously with real time analysis of reaction products and intermediates, infrared, ultraviolet other reflected electromagnetic analyses may be conducted on the reacting gases or catalyst surface.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: July 11, 2000
    Inventor: John T. Gleaves
  • Patent number: 6063633
    Abstract: A multicell holder e.g. a honeycomb or plate, or a collection of individual support particles, is treated with solutions/suspensions of catalyst ingredients to produce cells, spots or pellets holding each of a variety of combinations of the ingredients, is dried, calcined or treated as necessary to stabilize the ingredients in the cells, spots or pellets, then is contacted with a potentially reactive feed stream or batch e.g., biochemical, gas oil, hydrogen plus oxygen, propylene plus oxygen, CC12F2 and hydrogen, etc. The reaction occurring in each cell can be measured, e.g. by infrared thermography, spectroscopic detection of products or residual reactants, or by sampling, e.g. by multistreaming through low volume tubing, from the vicinity of each combination, followed by analysis e.g. spectral analysis, chromatography etc, or by observing temperature change in the vicinity of the catalyst e.g. by thermographic techniques, to determine the relative efficacy of the catalysts in each combination.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: May 16, 2000
    Assignee: The University of Houston
    Inventor: Richard C. Willson, III
  • Patent number: 6054098
    Abstract: This invention provides an apparatus for measuring ozone in which interference effects of SO.sub.2 are intended to be reduced. This invention comprises a reference gas line for generating reference gas with ozone removed by allowing the sample gas to pass through the ozone decomposer with silver wool used as a catalyst, a sample gas line for introducing the sample gas as it is, an ozone analyzer to which the reference gas line and the sample gas line are connected via a selector valve and which measures the ozone component in the sample gas by introducing the reference gas and the sample gas alternately at specified intervals, and a temperature controller installed to the ozone decomposer for setting the catalyst reaction temperature to a range from 100 to 130.degree. C.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: April 25, 2000
    Assignee: Horiba, Ltd.
    Inventors: Junji Kato, Toshikazu Ohnishi
  • Patent number: 5976889
    Abstract: A method and apparatus for detecting NO.sub.x by chemiluminescence. The apparatus includes a sample gas line having an inlet port for receiving a sample gas, a NO.sub.x converter connected to the sample gas line, a N.sub.2 diluting gas line connected to the sample gas line upstream from the NO.sub.x converter, a bypass exhaust lie connected to the sample gas line, and a chemiluminescence analyzer connected to the NO.sub.x converter. The sample gas, which contains a NO.sub.x component, is introduced to the sample gas line through an inlet portion. The sample gas is diluted with nitrogen gas from the nitrogen diluting gas line, and the NO.sub.x component in the sample gas is converted to NO by the NO.sub.x converter. The chemiluminescence analyzer detects the NO.sub.x component.
    Type: Grant
    Filed: October 8, 1997
    Date of Patent: November 2, 1999
    Assignee: Horiba Ltd.
    Inventors: Hitoshi Hirai, Masaru Miyai
  • Patent number: 5976890
    Abstract: The invention relates to a method for the quantitative determination of deuterium in samples containing hydrogen, and to a reduction oven for reducing gaseous or liquid substances containing hydrogen, which may be coupled directly to an isotope ratio mass spectrometer (IRMS), thereby permitting an online-coupled, reliable deuterium determination which can be automatized.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: November 2, 1999
    Assignee: UFZ-Umweltforschungszentrum Leipzig-Halle GmbH
    Inventors: Matthias Gehre, Reiner Hofling, Peter Kowski
  • Patent number: 5965451
    Abstract: The invention provides a gas sensor for selective detection of hydrocarbons in low-oxygen gases, having a capacitive element and a gas-permeable sensitive layer as a dielectric. The sensitive layer is a precious-metal-doped zeolite which has a regular crystalline structure made of primary pores whose diameter is in the order of the gas-kinetic diameter of the gas molecules to be detected.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: October 12, 1999
    Assignee: Dornier GmbH LHG
    Inventors: Carsten Plog, Werner Maunz
  • Patent number: 5948683
    Abstract: A selective catalytic material is used to catalyze selective oxidation of unsaturated hydrocarbons, e.g., olefins, in the presence of carbon monoxide. The catalytic material comprises phosphated ceria containing from 0.1 to 20, preferably from 1 to 5, percent by weight phosphate component (calculated as elemental phosphorus). The phosphated ceria may be made by mixing particles of ceria and a solution containing phosphates to disperse the desired amount of phosphate component on the ceria and calcining the particles after separation of them from the solution. The resulting selective catalytic material is contacted under oxidizing conditions with a gas stream containing an oxidant, e.g., air, carbon monoxide and one or more unsaturated hydrocarbons.
    Type: Grant
    Filed: October 18, 1997
    Date of Patent: September 7, 1999
    Assignee: Engelhard Corporation
    Inventors: Gerald S. Koermer, Ahmad Moini
  • Patent number: 5911953
    Abstract: A solid object carrying a catalyzer thereon is placed in a closed reaction chamber into which test gases are supplied and is heated up to a temperature of 1000.degree. C. Adsorbates are formed on the surface of the solid object under the test gas flow in the closed reaction chamber. Infrared radiations radiated from the adsorbates are emitted through an infrared-transmissive window hermetically formed on a wall of the closed reaction chamber, and are analyzed by an infrared radiation spectrometer and observed by a microscope. The infrared-transmissive window is cooled down by a cooling device attached thereto so that the temperature of the window does not exceed a certain level, e.g., 200.degree. C. Thus, the adsorbates formed on the solid object can be detected and analyzed under conditions where the test gas is actually flowing and the temperature of the solid object is elevated up to a high level.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: June 15, 1999
    Assignees: Nippon Soken, Inc., Horiba, Inc.
    Inventors: Itsuhei Ogata, Atsuhiro Sumiya, Tsukasa Satake
  • Patent number: 5789256
    Abstract: The present invention and its claims encompass principles, methods, apparatus, and applications for detection, quantification, and monitoring of responses of gases, vapors, aerosols, and mixtures thereof to initiators of exothermic reactions. While the invention can be utilized for any concentration level, the intended, normal utilization is for gases in which the concentrations of species capable of participating in exothermic chemistry are too low to support self-sustaining exothermic reactions leading to detonations or deflagrations as well as for gases in which other factors prevent the exothermic reaction chemistry from becoming self-sustaining.
    Type: Grant
    Filed: October 6, 1995
    Date of Patent: August 4, 1998
    Assignee: MW Technologies, Inc.
    Inventors: William H. Marlow, John P. Wagner
  • Patent number: 5766954
    Abstract: A continuous flow method of determining the quantitative isotopic composition of hydrogen comprised in a compound is disclosed, together with apparatus for carrying out the method. The method involves introducing the sample to be analysed into a flow of carrier gas which does not contain hydrogen, the carrier gas then being arranged to flow through a heated catalytic reactor which contain a chromium-based catalyst. The sample is pyrolysed in the catalytic reactor so as to form molecular hydrogen which is then analysed mass-spectrometrically. Preferably a gas chromatrograph is disposed before the catalytic reactor so that one or more components or a mixture may be separately analysed.
    Type: Grant
    Filed: April 26, 1996
    Date of Patent: June 16, 1998
    Assignee: Micromass Limited
    Inventors: Philip Antony Freedman, Timothy Graham Brockwell
  • Patent number: 5750999
    Abstract: An air contamination monitor includes a sample heater connectable to an air source such as an aircraft engine bleed air port. The heater causes any oil and other hydrocarbons in the sample air to decompose into CO.sub.2 and H.sub.2 O. A vacuum pump draws the heated air sample from the heater to a carbon dioxide analyzer. The response of the analyzer is recorded by means of a strip chart or paperless recorder.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: May 12, 1998
    Assignee: AlliedSignal Inc.
    Inventor: Richard Fox
  • Patent number: 5677190
    Abstract: An improved measurement cell and circuit for measuring the electrical characteristics of a liquid sample during exposure to radiation includes a glass cell formed of a main tube extending generally parallel to an elongated lamp emitting the radiation, and a pair of electrodes disposed axially within the sample tube. In the preferred embodiment, the ends of the cell are formed of glass twinbore tubing fused to the glass main tube, the bores retaining ends of the electrodes. Inlet and outlet tubes and a temperature sensing well may also be fused to the main tube. In an implementation for measurement of TOC in water by oxidation to CO.sub.2, the source comprises a low pressure mercury vapor lamp, and the electrodes are formed of solid Ti with catalytic TiO.sub.2 surfaces.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: October 14, 1997
    Assignee: Anatel Corporation
    Inventors: Paul C. Melanson, Robert L. Garvin, Lawrence K. de Martin, David A. Pane, James A. Valdez
  • Patent number: 5612225
    Abstract: This invention provides a process for determining the nitrogen content of a sample involving (a) combusting the sample in a combustion reactor in the presence of oxygen, which oxygen is introduced into the combustion reactor in pulse form; (b) reducing the resulting combustion gases by flowing them in a flow of helium or other noble carrier gas through a Cu-containing reduction reactor; (c) performing the steps of (i) making anhydrous in a water trap the reduced gases, (ii) flowing the reduced gases through a gas-chromatographic column in order to carry out a gas-chromatographic separation of N.sub.2 from CH.sub.4 possibly present within the reduced gases, and (iii) removing CO.sub.2 from the reduced gases using a CO.sub.2 trap, with the proviso that step (i) immediately precedes step (ii); and (d) analyzing the resulting gases by detecting thermal conductivity.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 18, 1997
    Assignee: Fisons Instruments S.p.A.
    Inventors: Marco Baccanti, Paolo Magni
  • Patent number: 5571724
    Abstract: The amount of smog formed in air and the smog concentration in air is determined by measuring the consumption of nitric oxide.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: November 5, 1996
    Assignee: Commonwealth Scientific and Industrial Research Organization
    Inventor: Graham M. Johnson
  • Patent number: 5567623
    Abstract: A system and method are provided for minimizing the effects of background signals in masking signals indicating the presence of substances to be detected such as contaminants in materials moving rapidly along a conveyor. The contaminants detected may include nitrogen containing compounds and hydrocarbons. The system and method of the present invention minimizes the number of falsely positive indications of the presence of such substances due to background signals and changes in background signals. The substances detected are divided into first and second sample portions and the respective portions are heated. The first heated portion is reacted with ozone to generate radiation by chemiluminescence having characteristic wavelengths related to substances in the first portion. The second portion heated is also reacted with ozone to generate radiation by chemiluminescence having characteristic wavelengths related to substances in the second portion.
    Type: Grant
    Filed: April 4, 1995
    Date of Patent: October 22, 1996
    Assignee: The Coca-Cola Company
    Inventors: David P. Rounbehler, David H. Fine, Eugene K. Achter, Stephen J. MacDonald, Daniel B. Dennison
  • Patent number: 5547876
    Abstract: Non-toxic combustion decomposition accelerators and processes for their production for elemental analysis. The non-toxic accelerators may be either single component or multicomponent. The single component non-toxic accelerators are glass frit, niobium pentoxide, and inorganic phosphate compounds. The multicomponent accelerators are formed from a combination of the foregoing, and most preferably from (a) one or more of niobium pentoxide, tungsten oxide and mixtures thereof, and (b) one or more of glass frit, inorganic phosphate compounds, and mixtures thereof.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: August 20, 1996
    Assignee: Leco Corporation
    Inventors: Ching-Fong Chen, Carlos Guerra
  • Patent number: 5500371
    Abstract: Apparatus and process for real time analysis of the intermediates and products of a gas phase chemical reaction catalyzed by a particulate catalyst. Real time analysis is conducted under high vacuum using a detector contained within a high vacuum cheer. The reactor is connected to the vacuum chamber but is outside thereof, allowing the reactor to be operated either at high vacuum or under moderate pressure. Reactors and reactor feed manifolds of varying configuration may be interchangeably connected to the vacuum chamber on an essentially modular basis. Only a single vacuum system is required for the apparatus. Reaction products may also be analyzed by methods such as gas chromatography. Simultaneously with real time analysis of reaction products and intermediates, infrared, ultraviolet other reflected electromagnetic analyses may be conducted on the reacting gases or catalyst surface.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: March 19, 1996
    Assignee: John T. Gleaves
    Inventor: John T. Gleaves
  • Patent number: 5445966
    Abstract: A general purpose technique called extractive hydrogenation analysis, useful for both trace component and imaging analysis of samples containing organic matter. In processes according to the invention, organic matter is thoroughly decomposed in the presence of a hydrogenation catalyst under substantially aqueous conditions into products, and one or more of the products is then detected.
    Type: Grant
    Filed: April 20, 1993
    Date of Patent: August 29, 1995
    Assignee: Northeastern University
    Inventors: Roger W. Giese, Mohammad S. Itani
  • Patent number: 5369034
    Abstract: A ventable container for materials to be heated (preferably digested) by microwave radiation includes a movable rupture diaphragm in a venting passageway in a closure or cover for such container. Such diaphragm is tightenable into place so that the container is sealed and in such sealed state is protected by the rupture diaphragm against pressures that could develop in the container that are higher than that for which it was designed. An important feature of the invention is that the rupture diaphragm is controllably movable, when desired, to open positions to vent the container during heating and afterward, and is resealable after venting. Because of the chemical reactivity of the reagents utilized in digestions an inner chemically resistant liner is desirably employed in conjunction with a physically stronger outer body, with the outer body giving the liner enough strength to withstand pressures developed during the heating.
    Type: Grant
    Filed: May 25, 1993
    Date of Patent: November 29, 1994
    Assignee: CEM Corporation
    Inventors: Wyatt P. Hargett, Sara E. Littau
  • Patent number: 5338515
    Abstract: This invention is a process for detecting low concentration levels of sulfur oxides (SO.sub.2) in a flowing gas stream (typically a combustion exhaust gas stream) and a catalytic SO.sub.2 sensor system which may be used in that process.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: August 16, 1994
    Assignee: Catalytica, Inc.
    Inventors: Ralph A. Dalla Betta, David R. Sheridan
  • Patent number: 5314827
    Abstract: An on-line mass spectrometric method and apparatus for the determination of the isotopic composition of at least oxygen, hydrogen and nitrogen in a compound or mixture of compounds. A mixture contained in syringe 6 is injected through injector 7 on a chromatographic column 1. Compounds eluting from the column 1 pass into a catalytic reactor 14 containing carbon and are decomposed to produce carbon monoxide, molecular nitrogen, and molecular hydrogen. These gases are analyzed by an isotope-ratio mass spectrometer 4 so that the isotopic composition of the oxygen, nitrogen and hydrogen comprised in the original compound can be determined. A second chromatographic column 24 may be provided to separate carbon monoxide and nitrogen before they are passed into the spectrometer 4, thereby allowing a low resolution spectrometer to be used for the analysis of both gases at m/e 28 daltons.
    Type: Grant
    Filed: September 18, 1990
    Date of Patent: May 24, 1994
    Assignee: Fisons plc
    Inventors: Hanns-Ludwig Schmidt, Ramiro Medina
  • Patent number: 5310683
    Abstract: A process and apparatus for the simultaneous measurement of sulfur-containing compounds and organic compounds with or without sulfur in their structures. A detector cell allows simultaneous measurement of compounds that can be ionized in a flame and thereby cause the electrical conductivity of the flame to increase, and the selective measurement of sulfur-containing compounds which simultaneously form sulfur monoxide. Sulfur monoxide, upon mixing with ozone, emits light from 240 to 450 nm. The intensity of the light can be measured and related to the concentration of sulfur in the sample, while changes in electrical conductivity of the flame measured by imposing a voltage across the cell quantifies the organic compounds irrespective of whether or not they contain sulfur.
    Type: Grant
    Filed: September 6, 1991
    Date of Patent: May 10, 1994
    Assignee: Sievers Research, Inc.
    Inventors: Richard Godec, Neil Johansen, Donald H. Stedman
  • Patent number: 5310681
    Abstract: A highly selective, sensitive, fast detection system and method are disclosed for detecting vapors of specific compounds in air. Vapors emanating from compounds such as explosives, or stripped from surfaces using heat and suction from a hand-held sample gun, are collected on surfaces coated with gas chromatograph (GC) material which trap explosives vapors but repel nitric oxide, then are desorbed and concentrated in one or more cold spot concentrators. A high speed gas chromatograph (GC) separates the vapors, after which specific vapors are decomposed in two pyrolyzers arranged in parallel and the resulting nitric oxide is detected. A low temperature pyrolyzer with silver produces NO from nitramines or nitrite esters; a high temperature pyrolyzer decomposes all explosives vapors to permit detection of the remaining explosives. Also disclosed is a series arrangement of pyrolyzers and gas chromatographs and an NO detector to time-shift detection of certain vapors and facilitate very fast GC analyses.
    Type: Grant
    Filed: June 9, 1993
    Date of Patent: May 10, 1994
    Assignee: Thermedics Inc.
    Inventors: David P. Rounbehler, Eugenie Hainsworth, David P. Lieb
  • Patent number: 5275957
    Abstract: Apparatus and methods for measurement of total organic carbon content of water, particularly of low relative organic content, are described, featuring a single sample cell for exposure of a static sample to ultraviolet radiation and comprising electrodes for measuring the conductivity of the water. The conductivity is monitored as a function of time and the second time derivative of the conductivity signal is monitored to indicate when the oxidation reaction has been completed. Compensation for the contribution to conductivity of the water sample made by the instrument is achieved by subtracting a quantity proportional to the first time derivative of the conductivity at a time when the second time derivative reaches zero, indicating that the oxidation reaction is complete, from the change in the total conductivity measurement, the remainder being equal to the contribution to conductivity made by oxidation of the organic content of the water.
    Type: Grant
    Filed: September 10, 1991
    Date of Patent: January 4, 1994
    Assignee: Anatel Corporation
    Inventors: Frederick K. Blades, Paul C. Melanson, Richard D. Godec
  • Patent number: 5246667
    Abstract: An analytical furnace includes a pair of generally vertically extending coaxially mounted spaced furnace tubes mounted to a support. The inner tube is made of a material which does not react with the specimen during pyrolysis to produce intereferring byproducts. An analytical sample crucible is supported above the support by a carbonaceous material which in the preferred embodiment comprises a combination of a carbon-felt packing material resting on the support and granular carbon black on which the crucible is placed. The material is selected to position the crucible in the hot zone of the furnace which includes a heater for heating an analytical sample for pyrolysis. The analytical furnace further includes a lance tube extending over and in coaxial alignment with the inner and outer furnace tubes for directing a sample and a carrier gas into the open mouth of the cup-shaped crucible.
    Type: Grant
    Filed: February 25, 1991
    Date of Patent: September 21, 1993
    Assignee: Leco Corporation
    Inventors: Wayne R. Hemzy, Carlos Guerra
  • Patent number: 5244811
    Abstract: A method and system for determining organic matter in an aqueous solution including an oxidizing agent are disclosed. The method includes contacting the solution with a semiconductor which is capable of photocatalytically oxidizing the organic matter, illuminating the semiconductor with light of a wavelength or having a spectrum whereby the semiconductor photocatalytically oxidizes the organic matter in the solution to form a photocatalytic by-product(s), and detecting the by-product(s).
    Type: Grant
    Filed: November 4, 1991
    Date of Patent: September 14, 1993
    Assignee: Commonwealth Scientific and Industrial Research Organization
    Inventor: Ralph W. Matthews
  • Patent number: 5235862
    Abstract: A sample handling apparatus includes a furnace which atomizes elements to be tested in a sample. A matrix modifier is added to the furnace. A quantity of the sample is subsequently added to the furnace. An additional quantity of the matrix modifier is then added into the furnace. The furnace is heated to atomization temperature to permit analysis of the sample to be tested.
    Type: Grant
    Filed: July 18, 1991
    Date of Patent: August 17, 1993
    Assignee: Hitachi, Ltd.
    Inventor: Katsuhito Harada
  • Patent number: 5234837
    Abstract: To measure the concentration in a gaseous medium of a known combustible gas a resistive element in the gaseous medium having a catalytic surface or being sensitive to variations in the concentration of the combustible gas in the gaseous medium is electrically heated, the value of a parameter representative of the gas concentration is detected and there is deduced therefrom, using a conversion law obtained previously by calibration, a measurement of said concentration. The element is heated periodically in cycles comprising a heating phase, a second phase in which the intensity I is controlled in such a way as to maintain the resistive element at a set point temperature and the stabilized value of the voltage U at the terminals of the detector is measured, and a third phase in which the heating power is reduced. On average the power of the electric current flowing during the second phase is substantially less than the heating current power.
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: August 10, 1993
    Assignee: Charbonnages de France
    Inventors: Antoinette Accorsi, Andree Wattier, Marc Kazmierczak
  • Patent number: 5227135
    Abstract: The present invention describes the process and apparatus for the simultaneous measurement of sulfur-containing compounds and organic compounds with or without sulfur in their structures. A detector cell is described that allows simultaneous measurement of compounds that can be ionized in a flame and thereby cause the electrical conductivity of the flame to increase, and the selective measurement of sulfur-containing compounds which simultaneously form sulfur monoxide. Sulfur monoxide, upon mixing with ozone, emits light from 240 to 450 nm. The intensity of the light can be measured and related to the concentration of sulfur in the sample, while changes in electrical conductivity of the flame measured by imposing a voltage across the cell quantifies the organic compounds irrespective of whether or not they contain sulfur.
    Type: Grant
    Filed: September 6, 1991
    Date of Patent: July 13, 1993
    Assignee: Sievers Research, Inc.
    Inventors: Richard Godec, Neil Johansen, Donald H. Stedman
  • Patent number: 5204270
    Abstract: A furnace with two hot zones holds multiple analysis tubes. Each tube has a separable sample-packing section positioned in the first hot zone and a catalyst-packing section positioned in the second hot zone. A mass flow controller is connected to an inlet of each sample tube, and gas is supplied to the mass flow controller. Oxygen is supplied through a mass flow controller to each tube to either or both of an inlet of the first tube and an intermediate portion between the tube sections to intermingle with and oxidize the entrained gases evolved from the sample. Oxidation of those gases is completed in the catalyst in each second tube section. A thermocouple within a sample reduces furnace temperature when an exothermic condition is sensed within the sample. Oxidized gases flow from outlets of the tubes to individual gas cells. The cells are sequentially aligned with an infrared detector, which senses the composition and quantities of the gas components.
    Type: Grant
    Filed: April 29, 1991
    Date of Patent: April 20, 1993
    Inventor: Robert B. LaCount
  • Patent number: 5102626
    Abstract: A matrix modifier of finely-divided metallic palladium dispersed to contact a metal constituent to improve analysis of the constituent during graphite furnace atomic absorption spectroscopy. The palladium interacts with a variety of metals in a sample to increase the vaporization temperatures of the metals. One way of contacting palladium with the metal analyte is to introduce it as a salt in solution with the sample into the graphite furnace along with a surfactant. A finely-divided metallic palladium having high surface area is produced in the furnace by introduction of hydrogen gas, which acts as a reducing agent, to reduce and maintain palladium in its metallic form at an early point in the temperature program, prior to evaporation of the surfactant.
    Type: Grant
    Filed: October 17, 1988
    Date of Patent: April 7, 1992
    Assignee: Varian Associates, Inc.
    Inventor: Lucinda M. Beach
  • Patent number: 5096834
    Abstract: A method for the determination of smoke concentration is disclosed which comprises heating a sample smoke containing a SOF (soluble organic fraction) component and a dry soot component to a temperature not lower than the boiling point of the SOF component and not higher than the flash point of the dry soot component during the presence of the action of an oxidation catalyst thereby allowing the dry soot component in the waste smoke to be determined by measurement with a smoke tester in a state not affected by the SOF component.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: March 17, 1992
    Assignees: Agency of Industrial Science and Technology, Ministry of International Trade & Industry
    Inventor: Keizo Saito
  • Patent number: 5070024
    Abstract: A hydrocarbon gas detection system utilizes a heat chamber or oven to maintain the system at a temperature that will support cracking of hydrocarbon gases. A gas chamber which is located inside the oven is used to contain the flow of gases under analysis and to pass these gases over a first temperature sensing device. A catalyzing material is associated with the first temperature sensing device, either by placing it very near the temperature sensing device or by coating the temperature sensing device with the catalyzing material. A second temperature sensing device is located inside the heat chamber or oven, either outside the gas chamber, or inside the gas chamber, but separated from the first temperature sensing device. The output of the first and second temperature sensing devices extend outside of the furnace to measurement and/or display instrumentation. With this system, the gas sample under analysis is passed through the gas chamber and brought into contact with the first temperature sensing device.
    Type: Grant
    Filed: July 12, 1988
    Date of Patent: December 3, 1991
    Assignee: Gas Research Institute
    Inventor: Thomas J. Bruno
  • Patent number: 5055266
    Abstract: A method capable of detecting low concentrations of a pollutant or other component in air or other gas, utilizing a combination of a heating filament having a catalytic surface of a noble metal for exposure to the gas and producing a derivative chemical product from the component, and an electrochemical sensor responsive to the derivative chemical product for providing a signal indicative of the product. At concentrations in the order of about 1-100 ppm of tetrachloroethylene, neither the heating filament nor the electrochemical sensor is individually capable of sensing the pollutant. In the combination, the heating filament converts the benzyl chloride to one or more derivative chemical products which may be detected by the electrochemical sensor.
    Type: Grant
    Filed: March 23, 1990
    Date of Patent: October 8, 1991
    Assignee: ARCH Development Corporation
    Inventors: Joseph R. Stetter, Solomon Zaromb, Melvin W. Findlay, Jr.
  • Patent number: 5039489
    Abstract: An improvement in an apparatus for carrying out chemical reactions is disclosed. The apparatus includes a housing defining a vacuum chamber, with a reactor located within the vacuum chamber. The improvement comprises a device disposed within the housing having a high-pressure outlet tube for engagement with the reactor, a bypass for placing the high-pressure outlet tube in fluid communication with the outside of the vacuum chamber, an orifice for placing the high-pressure outlet tube in fluid communication with the vacuum chamber and at least one valve for selectively opening or closing the bypass and the orifice. The device may be engaged and disengaged with the reactor by a manual shaft and gear arrangement for operating the reactor at higher pressures relative to the normal vacuum operation.
    Type: Grant
    Filed: April 17, 1990
    Date of Patent: August 13, 1991
    Inventors: John T. Gleaves, Patrick T. Harkins
  • Patent number: 5000920
    Abstract: A heat treatment device for the conversion of gaseous test samples into constituents determinable by a detector provides the possibility of obtaining the desired pyrolysis products even during the sampling, then feeding them directly to the detector. The device has a small structural shape, and is able to be carried and used easily and operated independently of an external energy supply. The heat treatment device is connectable to a number of different detectors. A container 1 through which the test gas can flow is provided with a chemical filler 5, 7, 8 capable of an exothermic reaction, and with a starter 4 initiating the reaction.
    Type: Grant
    Filed: March 3, 1988
    Date of Patent: March 19, 1991
    Assignee: Dragerwerk Aktiengesellschaft
    Inventors: Johannes Heckmann, Wolfgang Bather
  • Patent number: 4994398
    Abstract: An assistant combustion agent for use in a high-frequency combustion furnace is characterized by a blending together of tungsten powder and tin powder. The blended mixture is then molded into a form and a plurality of the molded forms are added to a sample in the furnace. The ratio of tungsten powder to tin powder is between about 80:20 to 60:40.
    Type: Grant
    Filed: February 18, 1988
    Date of Patent: February 19, 1991
    Assignee: Horiba, Ltd.
    Inventors: Takeshi Yamada, Mitsuhiko Chishiro, Katsuya Tsuji