Inorganic Carbon Compounds Patents (Class 436/133)
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Publication number: 20040067592Abstract: This invention relates to an improved process for the control of biocontamination in aqueous based polymeric emulsions contained in vessels having a headspace. The improvement comprises monitoring the carbon dioxide concentration in the headspace of the vessel using a direct reading carbon dioxide probe; and, then adding biocide when a preselected concentration of carbon dioxide above the atmospheric carbon dioxide concentration is reached.Type: ApplicationFiled: September 13, 2002Publication date: April 8, 2004Inventors: John Joseph Rabasco, Richard Henry Bott, Frank Kenneth Schweighardt
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Patent number: 6692970Abstract: A method and apparatus are provided for measuring the gas efflux from a substrate. In particular, one or more measuring chambers receive a gas enriched air from the substrate. A respiration system sends reference air having a known gas concentration to the measuring chamber. The reference air mixes with the gas enriched air to form a mixed air, which is returned to the respiration system. The respiration system then measures the gas efflux of the substrate over the given amount of time.Type: GrantFiled: January 5, 2001Date of Patent: February 17, 2004Assignee: The United States of America as represented by the Secretary of AgricultureInventors: John R. Butnor, Christopher A. Maier, Kurt H. Johnsen
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Patent number: 6682935Abstract: An optical sensor is proposed for determining gases in gas mixtures, especially for determining one gas component in the air, having a sensitive layer exposed to the gas and having a device for detecting a change in an optical property of the sensitive layer. The sensitive layer of the sensor contains a phosphorus or nitrogen-containing base having numerous and/or long-chain alkyl groups for the pH adjustment of the sensitive layer.Type: GrantFiled: June 28, 2001Date of Patent: January 27, 2004Assignee: Robert Bosch GmbHInventors: Thomas Brinz, Heidrun Potthast
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Patent number: 6677159Abstract: An apparatus and method for visually and continuously monitoring gaseous concentrations of electrophiles such as carbon dioxide. A coating composition comprising an organic binder, filler/pigment, an activator, and carbon dioxide sensitive color indicator interacts with a primed substrate to which it is applied for support. The coated primed substrate may then be used for estimation of carbon dioxide concentration by the detection of a substantially instantaneous and reversible color change of the coated primed substrate.Type: GrantFiled: December 2, 1998Date of Patent: January 13, 2004Assignee: Southwest Research InstituteInventor: William A. Mallow
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Publication number: 20030219907Abstract: An apparatus for notifying a user which gas tank(s) to connect to an enclosed chamber such as an incubator. The user inputs the desired setpoints for gasses such as O2 and CO2, and the corresponding gas level is determined. The determined gas level is compared with the setpoint of the gas and can display, which gas tank(s) should be hooked up to chamber.Type: ApplicationFiled: May 22, 2002Publication date: November 27, 2003Applicant: Kendro Laboratory Products, Inc.Inventors: Richard H. Bair, Bryan M. Elwood
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Patent number: 6653142Abstract: A method of automatically determining the content of inorganic carbon and/or total organic carbon in an aqueous purifying solution wherein, in program-controlled manner, (a) a sample of a predetermined volume is taken from the aqueous purifying solution; (b) if desired, the sample is freed of solids and/or homogenized; (c) if desired, the sample is diluted with water in a ratio which has been preset or is determined as a result of a preliminary analysis; (d) the inorganic carbon and/or total organic carbon is analysed using known methods; and (e) the result of the analysis is transmitted to a remote location and output and/or stored on a data carrier and/or used as the basis of further calculations. Program-controlled or automatic, externally-initiated checking of the measuring device is provided. Bath treatment measures may be implemented in program-controlled manner or in response to external triggering.Type: GrantFiled: March 29, 2001Date of Patent: November 25, 2003Assignee: Henkel Kommanditgesellschaft auf Aktien (Henkel KGaA)Inventors: Werner Opitz, Hans-Willi Kling, Andrea Wimschneider, Ibolya Bartik-Himmler, Bernd Schenzle, Wolfgang Krey
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Publication number: 20030198572Abstract: A rapid analysis method for the determination of Fries rearrangement products in aromatic polycarbonate resins utilizes in-line determination of polymer concentration and in-line fluorescence detection of Fries rearrangement products. The method avoids time consuming sample preparation required by previous methods, allows for separation of interfering low molecular weight components, and is suitable for automation.Type: ApplicationFiled: November 27, 2002Publication date: October 23, 2003Inventor: James Claude Carnahan
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Publication number: 20030199095Abstract: An ink composition for sensing carbon dioxide gas contains a pH indicator formed using a combination of two or more types of pH indicator components, binder, and solvent and allows easy visual observation of color changes of an indicating portion caused by the concentration of carbon dioxide gas. When the ink composition is applied to a carbon dioxide indicator and package, a pinhole and poor seal of a carbon-dioxide-ambient package are easily found.Type: ApplicationFiled: June 14, 2002Publication date: October 23, 2003Inventors: Kohei Yuyama, Minoru Oka, Hiroshi Honda, Shin Hamazaki, Shinya Ochiai, Noe Obinata, Hiroyuki Mizuma
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Patent number: 6623974Abstract: The invention provides an ozone hydroxy radical analysis method for a liquid carrying a suspension of organic matter. The analyser includes a reactor vessel 2 having sample inlets and outlets 3 and 4 respectively for a liquid stream 5. The reactor vessel 2 is connected to a control system 10 and is fed from an acid vessel 15, a base vessel 16 and an ozone generator 20. The reactor vessel 2 contains glass beads and a catalyst is introduced into the reactor vessel. With a manganese catalyst and glass beads, the manganese coats the glass beads which therefore retain catalyst with the reactor vessel.Type: GrantFiled: March 23, 2000Date of Patent: September 23, 2003Assignee: Analytical Developments LimitedInventors: Martin Horan, Seamus O'Mahony
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Patent number: 6623699Abstract: An analyzer compensates for gas flow perturbations by providing a makeup flow of carrier gas to maintain the pressure and/or flow rate of analyte and inert gas through a detector constant such that a accurate determination of a low concentration of an analyte in the presence of a high concentration of a second analyte can be accurately determined. In one embodiment, a carrier gas is introduced through a valve responsive to the detected pressure in the gas flow stream between a scrubber and a subsequent detector for maintaining the pressure constant during an analysis. In another embodiment of the invention, a flow transducer is positioned in the gas flow path between the scrubber and detector and coupled to a flow control valve coupled to introduce carrier gas as a function of detected gas flow such that the flow rate of gas into the detector is maintained constant.Type: GrantFiled: November 15, 2000Date of Patent: September 23, 2003Assignee: Leco CorporationInventors: Brian W. Pack, Carlos Guerra, Peter M. Willis, Joel C. Mitchell
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Publication number: 20030100124Abstract: This invention relates to a modulator for use in gas chromatographic analysis, adopted for alternatively trapping and releasing fractions of solutes in a length of a capillary column within a chromatographic oven, characterized in that it comprises at least one nozzle placed to spray at least one jet in at least one corresponding place along said capillary column length, said nozzle(s) being connected each to a source of liquid CO2 via a related valve, and means for alternatively opening said valve(s) for a predetermined time, to cause a jet of liquid CO2 to impinge for said predetermined time on said column place and to leave the oven atmosphere to heat said column place after said predetermined time. The modulator can be used in a conventional GC system or in a two dimensional GC system, for modulating the analytes fed to the second capillary column.Type: ApplicationFiled: April 16, 2002Publication date: May 29, 2003Inventor: Jan Beens
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Publication number: 20030087448Abstract: An airtight configuration for keeping down the permeation of corrosive gas from silicone adhesive, and for preventing corrosive gas from entering the case.Type: ApplicationFiled: September 20, 2002Publication date: May 8, 2003Applicant: HITACHI, LTDInventors: Hiroyuki Abe, Shinya Igarashi
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Publication number: 20030082816Abstract: A single pass analyzer includes multiple infrared sensors, a catalytic converter, a scrubber and a thermal conductivity cell all coupled in series to provide a single pass (i.e., one sample) analyzer which allows for fast analysis, allows for the speciation of hydrogen samples, requires no purging between different sample types, utilizes a single carrier gas, and eliminates molecular sieves and Shutze converters. The resultant analyzer provides improved quicker results with less plumbing (i.e., gas conduits and valving) in a single instrument.Type: ApplicationFiled: October 26, 2001Publication date: May 1, 2003Inventor: Carlos Guerra
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Publication number: 20030082822Abstract: A method and system for determining a concentration level of NOx in an exhaust stream from a combustion source. The method comprises capturing sample gas from the exhaust stream using a sampling device. NO2 in the sample gas is converted to NO by passing the sample gas through a catalytic NO2 converter. The method also comprises removing water from the sample gas by passing the sample gas through a dryer and determining a sample gas NO concentration level. The step of converting NO2 is performed at a temperature above the dew point temperature of the sample gas.Type: ApplicationFiled: March 6, 2002Publication date: May 1, 2003Inventors: William Steven Lanier, Glenn England
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Patent number: 6541268Abstract: A carbon dioxide sensor including a closed chamber having as a wall substantially water-tight, carbon dioxide-permeable membrane and containing two electrodes. The chamber contains a film of de-ionized water contacting the membrane and both of the electrodes. The change in conductance of the water due to absorption of carbon dioxide is measured.Type: GrantFiled: March 13, 2001Date of Patent: April 1, 2003Assignee: Alertis Medical ASInventors: Tor Inge Tonnessen, Peyman Mirtaheri
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Publication number: 20030032188Abstract: A diagnostic system for monitoring catalyst performance in an exhaust system comprises a plurality of treatment devices catalytically treating an exhaust gas stream, and a plurality of gas sensors for monitoring the catalyst performance of the treatment devices to determine when sulfur poisoning occurs. An on-board diagnostic system receives signals from the gas sensors, and, based upon response time differentials between sensors, determines whether the treatment devices are experiencing sulfur poisoning.Type: ApplicationFiled: August 10, 2001Publication date: February 13, 2003Inventors: Owen H. Bailey, Jean J. Balland, Sergio Quelhas, Bart Schreurs
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Publication number: 20030022386Abstract: Method and apparatus used to calculate the hydrogen sulfide and carbon dioxide loading of both rich and lean amine solutions used to remove acidic gas components from sour or production gases in order to produce a sweet or sales gas for transmission purposes. The amine solution is divided into three(3) liquid streams carrying different proportions of heat stable salts, hydrogen sulfide and carbon dioxide. Conductivity measurements are made on each of the streams and are converted to acid loading values for the amine. The acid loading values of the amine are used to obtain the hydrogen sulfide and carbon dioxide loading for the amine solution.Type: ApplicationFiled: July 30, 2001Publication date: January 30, 2003Applicant: SPARTAN CONTROLS LTD.Inventors: Jamie Swallow, Brent Richmond Young
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Publication number: 20030012696Abstract: The present invention concerns a continuous analyser of volatile organic compounds (10) comprising a circuit (18) for the sequential processing of air such that the air is drawn in by a pump (17) through a filter (11) and scanned by a first sensor (15) for CO/VOC and the second sensor (16) for H2O, either directly along a first pathway, or after passing through a cartridge (12) for retaining organic species along a second pathway; the switch over from one to the other of these two pathways being assured by an electric valve (13) controlled by a sequencer (14).Type: ApplicationFiled: August 28, 2002Publication date: January 16, 2003Inventor: Bernard Millancourt
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Patent number: 6506608Abstract: The oxygen and carbon dioxide content of expired respiratory gas is determined by measuring the mass and volume of the expired breath. From the composition of the inspired gas which may either be assumed or measured, the mass of the inspired volume may be determined, and since the inspired and expired breaths contain the same mass of nitrogen, the oxygen and carbon dioxide content of the expired breath may be determined. Measurements of temperature and humidity may be required to account for temperature and humidity changes between the inhalation and the exhalation or the inhaled gas may be adjusted in temperature and humidity to equalize the inhaled and exhaled temperature and humidity conditions. The mass and volume of the expiration and the volume mass of the inhalations are determined by an ultrasonic transit time system and a gas density sensor.Type: GrantFiled: August 20, 2001Date of Patent: January 14, 2003Assignee: Healthetech, Inc.Inventor: James R. Mault
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Publication number: 20030003590Abstract: A method and apparatus for measuring the concentration of at least one gaseous component and/or vaporous component of a gaseous mixture in which a controlled sensor flame is introduced into the gaseous mixture and at least one narrow spectral band in the controlled sensor flame is optically measured. The concentration of the gaseous component using a result obtained from the optical measuring of the at least one narrow spectral band is then calculated. The method of this invention is particularly suitable for substantially real-time control of combustion processes.Type: ApplicationFiled: June 28, 2001Publication date: January 2, 2003Inventors: Hamid A. Abbasi, David M. Rue
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Publication number: 20020168296Abstract: The invention describes a new device for the measurement of the partial pressure of carbon dioxide. The device is based on a simple construction and can be manufactured in a cost effective way. The pH dependency of the redox potential of organic substances is used to determine an electrical characteristic that depends on the partial pressure of carbon dioxide. The device for the potentiometric determination of the partial pressure of carbon dioxide consists of a housing with an opening for the entrance for gases, a gas permeable membrane, an electrolyte, at least one redox and one reference electrode with electrode contacts that transmit the electrode potential outwards through the housing. The gas permeable membrane has an electronically conductive layer that works as a redox electrode for a pH dependent redox system.Type: ApplicationFiled: April 25, 2002Publication date: November 14, 2002Inventor: Rudolf Gambert
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Publication number: 20020168773Abstract: The performance of an anion exchange resin is evaluated on-line by measuring inorganic carbonic acid concentrations at the inlet and at the outlet of an ion exchange resin vessel (such as a demineralizer vessel) of an ion exchange apparatus such as a condensate water demineralization system. Moreover, an MTC (Mass Transfer Coefficient) with respect to the inorganic carbonic acid is calculated and the dynamic performance and/or degree of degradation of the anion exchange resin are evaluated. The degree of degradation of the anion exchange resin is evaluated from the MTC and the replacement timing, lifetime, and throughput capacity for the anion exchange resin are judged.Type: ApplicationFiled: August 7, 2001Publication date: November 14, 2002Inventors: Tomoaki Ito, Masashi Fujita
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Publication number: 20020122746Abstract: A sensor main unit 1 is axially split into three sub-segments. A light-emitting element 2 is attached to one end portion, and a light-receiving element 3 is attached to the other end portion. A respiratory flow path 4 is formed so as to penetrate through the center portion. The sensor main unit 1 is attached to a position on the face below the nostrils, and respiratory gas from the nostrils is guided into the respiratory flow path 4 and is caused to cross over the optical axis connected the light-emitting element 2 and the light-receiving element 3, thereby measuring a carbon dioxide gas in the respiratory gas.Type: ApplicationFiled: March 8, 2002Publication date: September 5, 2002Applicant: NIHON KOHDEN CORPORATIONInventors: Shinji Yamamori, Yoshinobu Ono, Takeshi Kojima, Noriaki Todokoro
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Patent number: 6436347Abstract: A fast-response colorimetric carbon dioxide indicator device which is substantially insensitive to humidity and comprises a chemically inert substrate and an indicator composition supported by the substrate and responsive to exposure to carbon dioxide in expired respiratory air to undergo a color changing reaction. The indicator composition includes a pH sensitive dye and a basic substance having the general formula in which X is a nitrogen or phosphorus atom, each of R1, R2, R3 and R4 is an alkyl, Y− is an anion selected from the group consisting of hydroxide, fluoride, chloride, bromide, iodide, carbonate, and tetrafluoroborate, at least one of the alkyls R1, R2, R3 and R4 having at least 13 carbon atoms and at least one of the other alkyls having from 6 to 8 carbon atoms, the remaining alkyls, if any, having from 1 to 12 carbon atoms.Type: GrantFiled: May 30, 2000Date of Patent: August 20, 2002Assignee: Mincor ABInventor: Andras Cedeon
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Patent number: 6436717Abstract: The invention comprises a method for determining an analyte in which a dye solution is illuminated to induce a first and a second output light at a first and second wavelength, respectively, and the analyte concentration is determined from the measured first and second output intensities. The apparatus includes a probe (12) containing a dye solution, a light source (24), a frequency-sensitive photodetector (28) and a controller (90).Type: GrantFiled: March 23, 2000Date of Patent: August 20, 2002Assignee: Yellow Springs Optical Sensor Co. PLLInventor: Huan Ping Wu
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Publication number: 20020061596Abstract: A method for measuring an evolution rate of a gas from a sample includes equilibrating a sample with an alkaline solution and a pH indicator and permitting the alkaline solution to absorb formed carbon dioxide in an enclosed headspace. From the pH indicator at equilibrium is determined a time increment at which an increment of the alkaline solution is consumed by the CO2. Carbon dioxide evolution rate is calculated from the time increment, the volume increment, and the alkaline solution concentration. A device for performing this measurement includes a sample vial and a reaction chamber having an opening adapted for mating with a sample vial opening and an opening for receiving the solution. The reaction chamber is dimensioned for equilibrating the sample with the alkaline solution and for determining the time increment required for an increment of the alkaline solution to be consumed by CO2.Type: ApplicationFiled: November 14, 2001Publication date: May 23, 2002Inventors: Yuch Ping Hsieh, Yun-Hwa Peggy Hsieh
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Publication number: 20020031447Abstract: An optical gas sensor for determining a gas in a gas mixture, especially for determining a gas component in the air, is described, having a radiation source and having a sensitive layer positioned on a substrate. The sensitive layer of the sensor is porous and contains particles, which are optically transparent to a radiation emitted by radiation source and which lengthen the optical path of the radiation.Type: ApplicationFiled: June 22, 2001Publication date: March 14, 2002Inventors: Thomas Brinz, Heidrun Potthast
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Publication number: 20020028518Abstract: An optical sensor is proposed for determining gases in gas mixtures, especially for determining one gas component in the air, having a sensitive layer exposed to the gas and having a means for detecting a change in an optical property of the sensitive layer. The sensitive layer of the sensor contains a phosphorus or nitrogen-containing base having numerous and/or long-chain alkyl groups for the pH adjustment of the sensitive layer.Type: ApplicationFiled: June 28, 2001Publication date: March 7, 2002Inventors: Thomas Brinz, Heidrun Potthast
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Publication number: 20020013536Abstract: The oxygen and carbon dioxide content of expired respiratory gas is determined by measuring the mass and volume of the expired breath. From the composition of the inspired gas which may either be assumed or measured, the mass of the inspired volume may be determined, and since the inspired and expired breaths contain the same mass of nitrogen, the oxygen and carbon dioxide content of the expired breath may be determined. Measurements of temperature and humidity may be required to account for temperature and humidity changes between the inhalation and the exhalation or the inhaled gas may be adjusted in temperature and humidity to equalize the inhaled and exhaled temperature and humidity conditions. The mass and volume of the expiration and the volume mass of the inhalations are determined by an ultrasonic transit time system and a gas density sensor.Type: ApplicationFiled: August 20, 2001Publication date: January 31, 2002Inventor: James R. Mault
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Publication number: 20020001851Abstract: An apparatus and method for taking absorbance-based chemical measurements are described. In a specific embodiment, an indicator-based pCO2 (partial pressure of CO2) sensor displays sensor-to-sensor reproducibility and measurement stability. These qualities are achieved by: 1) renewing the sensing solution, 2) allowing the sensing solution to reach equilibrium with the analyte, and 3) calculating the response from a ratio of the indicator solution absorbances which are determined relative to a blank solution. Careful solution preparation, wavelength calibration, and stray light rejection also contribute to this calibration-free system. Three pCO2 sensors were calibrated and each had response curves which were essentially identical within the uncertainty of the calibration. Long-term laboratory and field studies showed the response had no drift over extended periods (months).Type: ApplicationFiled: January 31, 2001Publication date: January 3, 2002Inventor: Michael D. DeGrandpre
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Patent number: 6319723Abstract: An apparatus is disclosed which is capable of detecting a selected gas in a liquid sample to a sensitivity in the range of 10 to 10,000 parts per trillion. Such sensitivity is achieved by concentrating the selected gas in a sample without concentrating sources of ionic interference that are also present in the sample. Selective concentration of the gas is achieved by vaporizing the sample, correcting for non-ideal vaporization, selectively condensing the selected gas from the vapor, and detecting the selected gas. Methods for using the apparatus and detecting the selected gas are also disclosed.Type: GrantFiled: November 12, 1998Date of Patent: November 20, 2001Inventors: Eldon L. Jeffers, Edward M. Ejzak
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Publication number: 20010039054Abstract: A simple screening method is provided for determining biological variations among individuals in a smoking cessation program so that a therapy regimen can be adjusted appropriately for each individual. The method includes the steps of having an individual intake a predetermined dose of nicotine, taking a saliva sample at a predetermined time subsequent to intake of the dose of nicotine, and measuring the nicotine and cotinine levels in the sample. Thereafter, a ratio is calculated which includes both the nicotine and cotinine levels as an indicator of the rate of nicotine metabolism of the individual being screened.Type: ApplicationFiled: February 16, 1999Publication date: November 8, 2001Inventor: W. DALE HORST
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Patent number: 6277645Abstract: An indirect calorimeter is disclosed which comprises a test body (18) and a computation unit (24). In use, oxygen consumption in a respirator gas flow is determined by measuring inhaled and exhaled flow rates, and exhaled flow density, such that oxygen consumption is computed as a function of the exhaled mass.Type: GrantFiled: November 7, 2000Date of Patent: August 21, 2001Inventor: James R. Mault
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Patent number: 6267928Abstract: A method and apparatus for applying infrared radiation to a respiratory gas and detects a signal associated with the quantity of transmitted radiation for measuring the concentration of CO2 in the respiratory gas. The capnometer detects a maximum value of the detection signal from the thermal detector during the present inspiration phase, stores the detected maximum value in RAM, performs the first approximation, Kalman filtering or some other suitable method to compute a corrected value that is valid for the time being until a maximum value is detected in the next inspiration phase, and determines a density signal by calculating the difference between the corrected value and the detection signal.Type: GrantFiled: July 9, 1998Date of Patent: July 31, 2001Assignee: Nihon Kohden CorporationInventors: Shinji Yamamori, Hidehiro Hosaka, Kohei Ono, Masami Ito, Masayuki Inoue, Masaki Sugiura, Noriaki Todokoro, Yoshinobu Nakae
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Patent number: 6265221Abstract: A device for use in trapping and assaying 14CO2 in air exhaled by a person to which a 14CO labelled compound has been administered, in particular 14CO labelled urea, comprises first and second substantially flat oblong duct forming elements joined to each other at their edges except for one of their short edges and forming a duct between them. The first duct forming element includes a gas permeable matrix element for absorption of CO2. The device is provided with indicator means for visual detection of CO2 absorption and a film element of low &bgr;-radiation absorptivity interposed or interposable between the matrix element and a &bgr;-radiation measuring instrument. Also disclosed is a corresponding method.Type: GrantFiled: June 7, 1999Date of Patent: July 24, 2001Assignee: Noster System ABInventor: Stefan Nilsson
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Patent number: 6214628Abstract: In accordance with the present invention, a method of conducting an assay of a sample containing an analyte of interest includes the step of forming a mixture so as to bring a metal-ligand complex into interactive proximity with the sample containing the analyte of interest. The mixture is irradiated with electromagnetic light energy so as to cause emission of light indicative of the analyte of interest. The emitted light is measured, and the measurement of the emitted light is utilized to measure the analyte of interest. The metal-ligand complex can be [Re(bcp)(CO)3(4-COOHPy)]+, [Os(phen)2(aphen)]2+, [Os(tpy)(triphos)]2+, [Os(tppz)2]2+, and [Os(ttpy)2]2+, or the like. Also, the present invention is directed to a metal-ligand complex of the formula [Re(bcp)(CO)3(4-COOHPy)]+.Type: GrantFiled: January 14, 1998Date of Patent: April 10, 2001Inventors: Joseph R. Lakowicz, Felix Castellano, Zakir Murtaza
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Patent number: 6180414Abstract: A breath test for determining the rate of metabolism of a drug is described. First, a safe and effective amount of the drug, preferably appropriately labelled and most preferably isotopically-labelled, is administered to a subject. After a suitable time period, the exhaled breath of the subject is analyzed to determine the concentration of a metabolite. The concentration of the metabolite is then used to determine the rate of metabolism of the drug. A breath test kit is also described. Such a breath test kit would include an item or items necessary for performing at least one of the methods of determining the rate of metabolism of a drug in a subject. For example, such a breath test kit could include an isotopically-labelled drug to be administered to the subject.Type: GrantFiled: June 28, 1999Date of Patent: January 30, 2001Assignee: Oridion Medical Ltd.Inventor: Daniel E. Katzman
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Patent number: 6180413Abstract: A method for the determination of total organic carbon in an aqueous sample by trapping the organic matter on a sorbent which is carbon free and analyzing the sorbent by combustion and determination of total CO2 by IR.Type: GrantFiled: July 13, 1999Date of Patent: January 30, 2001Assignee: Westinghouse Savannah River CompanyInventor: Amy A. Ekechukwu
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Patent number: 6143568Abstract: A method for determining constituents in water, in particular the content of organic carbon and/or nitrogen, in which an aqueous sample is evaporated and combusted in at least one heating vessel (154a) provided with a heater (154), and the combustion product is delivered in a transporting gas stream to a detector (142) for determining the concentration of a gaseous compound of the constituent, wherein the heating vessel, or a first heating vessel, at the instant of delivery of the aqueous sample has a temperature below or at most within the range of the boiling temperature of the sample, and after delivery of the sample the temperature is increased, wherein the sample is heated by one and the same heater in a first step from an outset temperature below the boiling temperature to an evaporation temperature, and in a second step to a substantially higher temperature, and the combustion product is kept in closed circulation during the analysis.Type: GrantFiled: June 24, 1998Date of Patent: November 7, 2000Assignee: LAR Analytik und Umweltmesstechnik GmbHInventor: Ulrich Pilz
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Patent number: 6133042Abstract: 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: GrantFiled: February 10, 1998Date of Patent: October 17, 2000Assignee: Ford Global Technologies, Inc.Inventors: Margherita Zanini-Fisher, Eleftherios M. Logothetis, Jacobus H. Visser
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Patent number: 6087181Abstract: 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: GrantFiled: March 16, 1998Date of Patent: July 11, 2000Assignee: Symyx TechnologiesInventor: Pejun Cong
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Patent number: 6046054Abstract: The selectivity of response of resistive gas sensors to specific gases or vapors is improved by the selection of specified gas-sensitive materials which are not previously known for the applications described, which include detection of hydrocarbons in the presence of CO, H.sub.2 S, SO.sub.2, chlorine, NO.sub.2, CO.sub.2 (especially in low concentrations), CFC's, ammonia, free oxygen by determination of partial pressures, and numerous organic gases and vapors.Type: GrantFiled: December 9, 1997Date of Patent: April 4, 2000Assignee: Capteur Sensors & Analysers, Ltd.Inventors: Peter McGeehin, Patrick Timothy Moseley, David Edward Williams, Geoffrey Stephen Henshaw, Darryl Hirst Dawson, Laura Jane Gellman
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Patent number: 6010243Abstract: A thermal conductivity detector system within an incubator having an atmosphere of moisture and CO.sub.2 therein is calibrated this way: in a first phase, the incubator, after ambient air being supplied thereto, is closed with respect to further gas or air admission; in a second phase, and after a predetermined time interval, a CO.sub.2 measurement is made by means of the thermal conductivity cell, and upon deviation of the measured value from a CO.sub.2 zero value, the deviation is stored and utilized for 0.2 correction of the CO.sub.2 measured value. A CO.sub.2 tolerance range of measured values of, for example, .+-.0.2 vol. % CO.sub.2 is determined. After introduction of moisture or humidity into the chamber, a third phase is initiated for a predetermined time interval and run through so often until the CO.sub.2 measured value for the entire time interval remains within the CO.sub.2 tolerance range. After successful termination of the third phase, the moisture of said value of the CO.sub.Type: GrantFiled: August 7, 1997Date of Patent: January 4, 2000Assignee: Kendro Laboratory Products GmbHInventors: Karlheinz Hessler, Hubert Heeg
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Patent number: 5994144Abstract: When adsorbed gas is analyzed after metal, ceramics or metallic salt has been left in an environmental atmosphere for a predetermined period of time, an average concentration of specific gas over a long period of time can be accurately measured with an inexpensive small apparatus. Especially, porous metal or ceramics (transition metal oxide) are excellent in selective adsorption properties for NO.sub.x, porous ceramics (rare earth element oxide) are excellent in selective adsorption properties for CO.sub.2, and a specific chloride such as copper chloride and silver chloride is excellent in selective adsorption properties for SO.sub.2. A test kit accommodating such test pieces in a case, a protective case for the test kit to put the test kit into practical use, an umbrella and a forced air blowing unit are also disclosed.Type: GrantFiled: January 4, 1994Date of Patent: November 30, 1999Assignee: Fujitsu LimitedInventors: Eiichi Nakajima, Yasuo Udoh, Tsutomu Iikawa, Toshisuke Kitakohji, Teruo Motoyoshi, Takashi Furusawa, Shiori Yamazaki, Masao Nakayama, Michiko Satoh, Shigeru Fukushima, Mayumi Itabashi
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Patent number: 5993640Abstract: The CaCO.sub.3 content of a scrubbing suspension, especially for a desulfurizing apparatus for flue gas is measured by injecting an acid into a constant mass flow of the suspension circulating along a bypass and measuring the pH before and after such injection. The change in pH is compared with reference measurements and used as a basis for calculating the CaCO.sub.3 concentration.Type: GrantFiled: July 31, 1998Date of Patent: November 30, 1999Assignee: Lurgi Lentjes Bischoff GmbHInventor: Theo Risse
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Patent number: 5994147Abstract: A method for determining the concentration of acid-gases in an amine-regeneration system, such as is typically found in a natural gas refining plant, having a device for measuring the pH of the system from which the concentration of the acid-gases complexed and the amine can be calculated using an empirically-derived relationship between acid-gas concentration and pH. The invention also includes a system for controlling amine regeneration based upon the above described determining method.Type: GrantFiled: May 23, 1997Date of Patent: November 30, 1999Assignee: Union Pacific Resources Co.Inventors: Eduardo F. Rodriguez, Robert R. Craycraft
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Patent number: 5962335Abstract: A breath test for determining the rate of metabolism of a drug is described. First, a safe and effective amount of the drug, preferably appropriately labelled and most preferably isotopically-labelled, is administered to a subject. After a suitable time period, the exhaled breath of the subject is analyzed to determine the concentration of a metabolite. The concentration of the metabolite is then used to determine the rate of metabolism of the drug. A breath test kit is also described. Such a breath test kit would include an item or items necessary for performing at least one of the methods of determining the rate of metabolism of a drug in a subject. For example, such a breath test kit could include an isotopically-labelled drug to be administered to the subject.Type: GrantFiled: January 3, 1997Date of Patent: October 5, 1999Assignee: Oridion Medical Ltd.Inventor: Daniel E. Katzman
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Patent number: 5910448Abstract: The process of this invention comprises providing a membrane for separating CO.sub.2 into a first CO.sub.2 sample phase and a second CO.sub.2 analyte phase. CO.sub.2 is then transported through the membrane thereby separating the CO.sub.2 with the membrane into a first CO.sub.2 sample phase and a second CO.sub.2 analyte liquid phase including an ionized, conductive, dissociated CO.sub.2 species. Next, the concentration of the ionized, conductive, dissociated CO.sub.2 species in the second CO.sub.2 analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO.sub.2 to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO.sub.2 in the first CO.sub.2 sample phase. Finally, the chemically amplified, ionized, conductive, dissociated CO.sub.2 species is introduced to a conductivity measuring instrument. Conductivity changes in the chemically amplified, ionized, conductive, dissociated CO.sub.Type: GrantFiled: April 4, 1997Date of Patent: June 8, 1999Assignee: Umpqua Research CompanyInventors: James E. Atwater, James R. Akse, Jeffrey DeHart
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Patent number: 5908789Abstract: The invention relates to a method and apparatus for determining the concentration of at least carbon dioxide in a gas mixture on the basis of the absorption of infrared radiation (2), said apparatus comprising: a radiation source (1), the radiation emitted thereby being aligned to travel through a measuring cell (4) containing a gas mixture (6) to be analyzed; an optical band-pass filter (10), which is transmissive to a first wavelength band and positioned on the path of radiation emerging from the measuring cell or entering into the measuring cell through which the radiation passes; and a first detector (14), positioned in the radiating direction downstream of said first band-pass filter and used for detecting the radiation intensity falling thereon. Said optical band-pass filter (10) has a band-pass which lies within the wavelength range of 4.38 .mu.m-4.47 .mu.m for measuring the total concentration of carbon dioxide by means of the absorption spectrum of a molecule .sup.13 CO.sub.Type: GrantFiled: March 12, 1997Date of Patent: June 1, 1999Assignee: Instrumentarium OyInventor: Kurt Peter Weckstrom
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Patent number: 5854078Abstract: Novel sensor devices composed of a crystalline colloidal array (CCA) polymerized in a hydrogel are disclosed. The hydrogels are characterized as being capable of shrinking and swelling in response to specific stimuli applied thereto. As the hydrogels shrink or swell, the lattice structure of the CCA embedded therein changes, thereby changing the wavelength of light diffracted by the CCA. Thus by monitoring the change in diffracted wavelength, the concentration of a stimulus is determined. The gels can be modified to sense numerous different stimuli. The sensor devices are specific in that they are modified to react with only one species or family of species. These sensors have various applications in areas including, for example, environmental and chemical systems, chemomechanical systems, sensor devices and medical diagnostic tools. Various methods for making and using these devices are also disclosed.Type: GrantFiled: March 17, 1997Date of Patent: December 29, 1998Assignee: University of PittsburghInventors: Sanford A. Asher, John H. Holtz