With Means To Supply The Gas Patents (Class 250/379)
  • Patent number: 10969371
    Abstract: A method of detecting gas includes determining and storing, by a controller, a zero level of a photoionization detector using ambient air inflow when an ultraviolet lamp is in a turned OFF state, wherein the stored zero level is based on an ambient temperature; sampling, by the controller, an output of a detector electrode of the photoionization detector when the ultraviolet lamp is in a turned ON state; and comparing the sampled output of the detector electrode to the stored zero level to determine if a threshold concentration of a gas is present.
    Type: Grant
    Filed: August 7, 2020
    Date of Patent: April 6, 2021
    Assignee: Honeywell International Inc.
    Inventors: Guangli Xie, Bo Chen, Zhanghua Wu, Yaofu Gong
  • Patent number: 10782273
    Abstract: A method of detecting gas with a photoionization detector (PID) system. The method includes powering on a photoionization detector, turning off an ultraviolet lamp of the photoionization detector by a controller of the PID system and keeping it turned off during the zero calibration procedure, flowing ambient air from a surrounding environment by a fan of the photoionization detector system past a detector electrode of the photoionization detector, processing an output of the detector electrode by the controller to determine a zero level of the photoionization detector, and storing the zero level in a memory of the photoionization detector system. The photoionization detector system in a detecting mode compares an output of the detector electrode to the zero level to determine if a threshold concentration of a gas is present.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: September 22, 2020
    Assignee: Honeywell International Inc.
    Inventors: Guangli Xie, Bo Chen, Zhanghua Wu, Yaofu Gong
  • Patent number: 10254439
    Abstract: Implementations are directed to monitoring and reporting on actual hazardous conditions at a facility receiving data associated with a site, the site being susceptible to potentially hazardous conditions, and include actions of determining that a hazardous condition is present at the site, processing the data based on one or more models to provide output data, processing the output data to provide indicator data for providing a graphical representation of the site, the graphical representation providing a graphical depiction of the hazardous condition, and providing the indicator data to one or more user devices, the indicator data being processed by each of the one or more user devices to display the graphical representation.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: April 9, 2019
    Assignee: WellAware Holdings, Inc.
    Inventor: Cody James Lee
  • Patent number: 10061093
    Abstract: A method, system, and apparatus are disclosed for a ruggedized photonic crystal (PC) sensor packaging. In particular, the present disclosure teaches a ruggedized packaging for a photonic crystal sensor that includes of a hermetic-seal high-temperature jacket and a ferrule that eliminate the exposure of the optical fiber as well as the critical part of the photonic crystal sensor to harsh environments. The disclosed packaging methods enable photonic crystal based sensors to operate in challenging environments where adverse environmental conditions, such as electromagnetic interference (EMI), corrosive fluids, large temperature variations, and strong mechanical vibrations, currently exclude the use of traditional sensor technologies.
    Type: Grant
    Filed: October 14, 2016
    Date of Patent: August 28, 2018
    Assignee: The Boeing Company
    Inventors: Michael A. Carralero, Eric Y. Chan, Dennis G. Koshinz
  • Patent number: 10041908
    Abstract: A VOC detection sensor includes: a photoemission acceleration unit including a first electrode and a second electrode spaced apart from each other to face each other and a power source unit forming an electric field between the first electrode and the second electrode, photoemission means disposed within a space formed by the first electrode and second electrode of the photoemission acceleration unit and emitting photoelectrons, a light source supplying light energy by which the photoemission means emits photoelectrons, and an ammeter measuring the amount of charges flowing between the first electrode and the second electrode, wherein VOCs in the space between the first electrode and the second electrode are ionized through a collision against photoelectrons accelerated by the photoemission acceleration unit, and the ammeter detects a concentration of the VOCs by measuring the amount of charges formed by the ionized VOCs between the first electrode and the second electrode.
    Type: Grant
    Filed: September 13, 2016
    Date of Patent: August 7, 2018
    Assignee: INDUSTRY-ACADEMIC COOPERATION FOUNDATION YONSEI UNIVERSITY
    Inventors: Jong Baeg Kim, Kyounghoon Lee, Yunsung Kang
  • Patent number: 9576776
    Abstract: The invention provides a charged particle sensor (10) for detecting and measuring ionic current generated by charged particles resulting from ionization processes, comprising: a housing (16), a detection electrode (14) enclosed within the housing for collecting the charged particles, and an electrometer (12) having an input connected to the detection electrode for receiving a DC input signal therefrom and an output (18) for supplying a DC measurement signal as output. The housing comprises an electrostatic screen (16) for screening the detection electrode from external electric fields, whereby to reduce the sensitivity of the detection electrode to such fields.
    Type: Grant
    Filed: October 30, 2013
    Date of Patent: February 21, 2017
    Assignee: University of Sussex
    Inventor: Robert Prance
  • Patent number: 9500808
    Abstract: A method, system, and apparatus are disclosed for a ruggedized photonic crystal (PC) sensor packaging. In particular, the present disclosure teaches a ruggedized packaging for a photonic crystal sensor that includes of a hermetic-seal high-temperature jacket and a ferrule that eliminate the exposure of the optical fiber as well as the critical part of the photonic crystal sensor to harsh environments. The disclosed packaging methods enable photonic crystal based sensors to operate in challenging environments where adverse environmental conditions, such as electromagnetic interference (EMI), corrosive fluids, large temperature variations, and strong mechanical vibrations, currently exclude the use of traditional sensor technologies.
    Type: Grant
    Filed: May 9, 2012
    Date of Patent: November 22, 2016
    Assignee: THE BOEING COMPANY
    Inventors: Michael A. Carralero, Eric Y. Chan, Dennis G. Koshinz
  • Patent number: 9103752
    Abstract: A radon collection cartridge and a radon extraction system for economically reducing or removing radon gas danger are disclosed. The cartridge and system can include one or more screens having a plurality of spaced openings. Loosely stacked screens can be secured within a frame to form a cartridge with a labyrinth-like airflow path. At least some of the screens are provided with a surface that collects and retains radon materials. The radon extraction system can include at least one of the above described screens or cartridges. The system may also include a fan assembly having a motor connected to a fan wheel to induce an air flow through the screen(s) or cartridge(s). A controller may be provided that operates the fan assembly motor. The controller can operate the fan motor based on the operational state of a gas burning appliance.
    Type: Grant
    Filed: June 2, 2014
    Date of Patent: August 11, 2015
    Inventor: Armand D. Maanum
  • Publication number: 20140197323
    Abstract: A radiation detection assembly includes an ionization chamber for detecting radiation. The ionization chamber includes a volume of pressurized gas. An exterior enclosure houses the ionization chamber within an interior volume. The exterior enclosure includes a frangible section. A relief assembly defines a gas flow path from the ionization chamber to the frangible section of the exterior enclosure. The frangible section releases pressure from within the ionization chamber when the pressurized gas within the ionization chamber exceeds a predetermined pressure such that at least some of the pressurized gas flows through the relief assembly and through the frangible section of the exterior enclosure. The pressurized gas is then released to an exterior of the exterior enclosure. A method of reducing pressure within a radiation detection assembly is also provided.
    Type: Application
    Filed: January 17, 2013
    Publication date: July 17, 2014
    Applicant: General Electric Company
    Inventors: Edward Joseph Baus, Joseph Paul Constant
  • Patent number: 8680476
    Abstract: A beta radiation monitor (70,90), comprising a gas flow proportional detector (60) for detecting beta radiation emitted by a beta emitter external to the detector; a fill gas supply (51) configured to supply a fill gas to the detector, wherein the fill gas comprises nitrogen; a temperature sensor (72) for measuring temperature; and a controller (64) in communication with the temperature sensor for adjusting an operational parameter of the monitor in accordance with the measured temperature. The operational parameter may comprise a voltage applied across the fill gas, which may be thermistor controlled, or a beta radiation detection threshold of the detector. The fill gas is supplied by a nitrogen generator. The gas flow proportional detector may be a large-area detector.
    Type: Grant
    Filed: December 9, 2009
    Date of Patent: March 25, 2014
    Assignee: Thermo Electron Limited
    Inventors: Neil Andrew Webster, John Stanley Usher, Christopher Edward Hill, Michael Hodgson
  • Patent number: 8223913
    Abstract: A method for measuring high-energy radiation includes applying a voltage pulse to electrodes in an ion chamber filled with a gas capable of forming charged ions by the high-energy radiation; measuring an ion current signal related to ion currents induced by the voltage pulse; and determining a magnitude of the high-energy radiation based on the ion current signal.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: July 17, 2012
    Assignee: Thermo Fisher Scientific Inc.
    Inventors: Michael Masterov, Alexander Joseph Esin
  • Patent number: 8188442
    Abstract: Electron capture detector for use with an effluent stream from a gas chromatograph includes a non-radioactive electron source means and an adjacent ionization chamber in which electron capture take place. The detector comprises two partial chambers, of which one contains the electron source, and the other contains connections for input and output of analysis gas as well as a collector electrode for detecting ions. The collector electrode and the electron source are each of cylindrical configurations, and are coaxially aligned but are spaced apart with respect to each other. The electron current to the collector electrode provides an indication of the presence of electronegative constituents in the gas passing into the second partial chamber.
    Type: Grant
    Filed: June 7, 2009
    Date of Patent: May 29, 2012
    Inventors: Mahmoud Tabrizchi, Hamed Bahrami
  • Publication number: 20110315889
    Abstract: A beta radiation monitor (70,90), comprising a gas flow proportional detector (60) for detecting beta radiation emitted by a beta emitter external to the detector; a fill gas supply (51) configured to supply a fill gas to the detector, wherein the fill gas comprises nitrogen; a temperature sensor (72) for measuring temperature; and a controller (64) in communication with the temperature sensor for adjusting an operational parameter of the monitor in accordance with the measured temperature. The operational parameter may comprise a voltage applied across the fill gas, which may be thermistor controlled, or a beta radiation detection threshold of the detector. The fill gas is supplied by a nitrogen generator. The gas flow proportional detector may be a large-area detector.
    Type: Application
    Filed: December 9, 2009
    Publication date: December 29, 2011
    Inventors: Neil Andrew Webster, John Stanley Usher, Christopher Edward Hill, Michael Hodgson
  • Patent number: 7737424
    Abstract: A high strength window for a radiation detection system includes a plurality of intersecting ribs defining a grid having openings therein with tops of the ribs terminate substantially in a common plane. The intersecting ribs are oriented non-perpendicularly with respect to each other and define non-rectangular openings. The window also includes a support frame around a perimeter of the plurality of intersecting ribs, and a film disposed over and spanning the plurality of intersecting ribs and openings. The film is configured to pass radiation therethrough. An associated radiation detection system includes a sensor disposed behind the window. The sensor is configured to detect radiation passing through the high strength window.
    Type: Grant
    Filed: June 1, 2007
    Date of Patent: June 15, 2010
    Assignee: Moxtek, Inc.
    Inventors: Degao Xu, Eric C. Anderson, Keith W. Decker, Raymond T. Perkins
  • Publication number: 20090242783
    Abstract: Electron capture detector for use with an effluent stream from a gas chromatograph includes a non-radioactive electron source means and an adjacent ionization chamber in which electron capture take place. The detector comprises two partial chambers, of which one contains the electron source, and the other contains connections for input and output of analysis gas as well as a collector electrode for detecting ions. The collector electrode and the electron source are each of cylindrical configurations, and are coaxially aligned but are spaced apart with respect to each other. The electron current to the collector electrode provides an indication of the presence of electronegative constituents in the gas passing into the second partial chamber.
    Type: Application
    Filed: June 7, 2009
    Publication date: October 1, 2009
    Applicant: Isfahan University of Technology
    Inventors: Mahmoud Tabrizchi, Hamed Bahrami
  • Publication number: 20080210879
    Abstract: The invention concerns a method for measuring the leakage rate of an activated carbon filter, characterised in that it comprises the following steps: injecting into the circuit comprising the filter to be tested a gas mixture comprising a carrier gas and a gas trappable by said filter to be tested, sampling, upstream and downstream of the filter, a relative amount of said gas mixture in storage means, measuring the amount of trappable gas contained in each of the storage means using a photoionisation chromatograph, determining the leakage rate by comparing the relative amount of trappable gas present downstream and the relative amount of trappable gas present upstream of the filter.
    Type: Application
    Filed: July 7, 2006
    Publication date: September 4, 2008
    Applicant: Maintenance Securite Installation Service
    Inventor: Pascal Gontier
  • Patent number: 7368726
    Abstract: A method for measuring high-energy radiation flux includes applying a positive voltage to electrodes in an ion chamber filled with a gas capable of forming charged ions by a high-energy radiation, measuring a positive ion current signal related to ion currents induced by the positive voltage, applying a negative voltage to the electrodes, measuring a negative signal related to ion currents induced by the negative voltage, and determining a magnitude of the high-energy radiation flux based on the ion current signal.
    Type: Grant
    Filed: February 2, 2005
    Date of Patent: May 6, 2008
    Assignee: Thermo Fisher Scientific Inc.
    Inventors: Alexander Joseph Esin, Michael Masterov
  • Patent number: 7196336
    Abstract: An apparatus for injecting plasma in the atmosphere is provided, including a plurality of dielectric panels (13a, 13b, 13c), and 13d, which are disposed in parallel at predetermined intervals, a gas supply portion (14), to which the dielectric panels (13a, 13b, 13c, and 13d) are fixed and which supplies a gas to spaces between the dielectric panels (13a and 13b), between the dielectric panels (13b and 13c), and between the dielectric panels (13c and 13d), power electrodes (15a, 15b, and 15c), which are linearly installed near the gas supply portion (14) and between the dielectric panels (13a and 13b, between the dielectric panels 13b and 13c, and between the dielectric panels 13c and 13d), respectively, ground electrodes (16a, 16b, 16c, and 16d), which are formed in the ends of the dielectric panels (13a, 13b, 13c, and 13d), respectively, and a high frequency generator (17), which applies high frequency power to the power electrodes (15a, 15b, and 15c) and the ground electrodes (16a, 16b, 16c, and 16d).
    Type: Grant
    Filed: April 26, 2004
    Date of Patent: March 27, 2007
    Assignee: Industry-University Cooperation Foundation Hanyang University
    Inventors: Kyu Sun Chung, Yong Sup Choi, Myoung Jae Lee
  • Patent number: 6765198
    Abstract: An ion trap mobility spectrometer is provided. The ion trap mobility spectrometer employs algorithms to simultaneously detect and analyze both positive and negative plasmagrams. Selectivity is improved by detecting the presence of peaks in both spectra and setting logic filters which require the presence or absence of certain peaks in both spectra. Selectivity is improved by looking for two peaks in the two spectra.
    Type: Grant
    Filed: March 20, 2002
    Date of Patent: July 20, 2004
    Assignee: General Electric Company
    Inventors: Anthony Jenkins, William J. McGann
  • Patent number: 6717153
    Abstract: Ions produced by radioactive gases present in air impact on the sensitivity of contamination measuring instruments which detect ions generated by radioactive materials present on an item. Methods and apparatus address this issue by conducting a measurement of ions generated in a chamber by gaseous emitters and other background events in a volume of medium and deducting this from a measurement of ions generated in another chamber by the item as well as the gaseous emitters and background events. The variation of the gaseous emitters present within the medium is addressed by moving the medium about. An alternative solution uses a medium free of gaseous emitters having a significant level, for instance by sealed storage of air prior to its use in a method and instrument.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: April 6, 2004
    Assignee: British Nuclear Fuels PLC
    Inventors: Richard Donald Gunn, Thomas Dockray
  • Publication number: 20030030006
    Abstract: A gaseous supply system and method for operating the same is disclosed for supplying at least one gaseous source material to an ion source chamber for use with an ion implanter including at least one gas supply module in gaseous communication with an ion source chamber including at least one pneumatic valve to control the delivery of at least one gaseous source material to the ion source chamber for generation of source material ions for implantation including a driver gas source in communication with said at least one pneumatic valve for operating the at least one pneumatic valve said driver gas source having a different atomic mass unit than the source material ions for implantation generated from the at least one gaseous source material.
    Type: Application
    Filed: August 10, 2001
    Publication date: February 13, 2003
    Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventor: Lu-Chang Chen
  • Patent number: 6455859
    Abstract: A method and apparatus for monitoring alpha contamination are provided in which ions generated in the air surrounding the item, by the passage of alpha particles, are moved to a distant detector location. The parts of the item from which ions are withdrawn can be controlled by restricting the air flow over different portions of the apparatus. In this way, detection of internal and external surfaces separately, for instance, can be provided. The apparatus and method are particularly suited for use in undertaking alpha contamination measurements during the commissioning operations.
    Type: Grant
    Filed: July 11, 2000
    Date of Patent: September 24, 2002
    Inventors: Christopher Henry Orr, Craig Janson Luff, Thomas Dockray, Duncan Whittemore Macarthur
  • Patent number: 6429020
    Abstract: A sensor for detecting the flame occurring during a flashback condition in the fuel nozzle of a lean premix combustion system is presented. The sensor comprises an electrically isolated flashback detection electrode and a guard electrode, both of which generate electrical fields extending to the walls of the combustion chamber and to the walls of the fuel nozzle. The sensor is positioned on the fuel nozzle center body at a location proximate the entrance to the combustion chamber of the gas turbine combustion system. The sensor provides 360° detection of a flashback inside the fuel nozzle, by detecting the current conducted by the flame within a time frame that will prevent damage to the gas turbine combustion system caused by the flashback condition.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: August 6, 2002
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Jimmy Dean Thornton, George Alan Richards, Douglas L. Straub, Eric Arnold Liese, John Lee Trader, Jr., George Edward Fasching
  • Patent number: 6023169
    Abstract: ECD with a non-radioactive electron source for generation of ions in a reaction chamber. The reaction chamber consists of two partial chambers, of which one is evacuated and contains the electron source, and the other contains connections for the feeding in of analysis gas as well as a collector electrode for detecting ions. The partition between the two partial chambers is permeable for electrons from the source but impermeable for gas molecules. The electron source may be a thermoemitter or a photocathode, which is irradiated from the outside through a window. In this way, contact between the analysis substance and the electron source is prevented, which increases measurement stability.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: February 8, 2000
    Assignee: Bruker-Saxonia Analytik GmbH
    Inventors: Vitali Lvovich Budovich, Alexei Anatolevich Mikhailov, Gerd Arnold
  • Patent number: 5920072
    Abstract: An ionization detector having an upper ionization chamber, a lower ionization chamber, and a radioactive source located in the upper ionization chamber but shielded from the lower ionization chamber by a barrier. A substantially constant fluid stream of detector gas is supplied to the upper ionization chamber so as to fill the upper ionization. The radioactive particle emitter is disposed on the periphery of the interior of the upper ionization chamber so as to generate a constant supply of alpha particles into the internal volume defined by the upper ionization chamber. The interaction of the alpha particles and the detector gas generates metastables and photons as the alpha particles traverse a portion of the volume in the upper ionization chamber. The lower ionization chamber is coupled to the upper ionization chamber so as to receive the detector gas flow and the metastables.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: July 6, 1999
    Assignee: Hewlett-Packard Co.
    Inventor: Mahmoud F. Abdel-Rahman
  • Patent number: 5861629
    Abstract: Method of quantitatively detecting material in a sample, whereby the material is in the form of submicrometric particles covered by a photoemitting substance, and a device for practicing the method. The material in the sample is heated to a photoemitting state and subjected while in that state to photoemission measurement. The proportion of material in the sample is determined from the signal obtained from that measurement by comparison with empirical data obtained from a reference sample containing a previously detected quantity of the material or by comparison with data obtained for the material by calibration.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: January 19, 1999
    Assignee: Forschungszentrum Julich GmbH
    Inventors: Helmut Hackfort, Georg Hinzen
  • Patent number: 5804828
    Abstract: Electron capture detector for use with an effluent stream from a gas chromatograph includes an ionization cell and a sample inlet system connected to the ionization cell for providing an effluent fluid having a sample concentration therein. In the preferred constant-current, variable frequency mode of operation, a cell current is measured and compared to the reference current. The pulse rate is then adjusted to maintain a constant cell current. The pulse rate is converted to a voltage, processed according to a novel linearization formula, and recorded. The ionization cell includes a radioactive ionization source and the ionization cell defines an optimized cell volume in which the electron capture reaction is forced to occur according to a concentration mode of operation. Improved sensitivity in the electron capture detector may be achieved by restricting the effective radioactivity in the ionization cell to be in the range of 0.5 to 3 milliCuries, and preferably in the range of 1 to 2 milliCuries.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: September 8, 1998
    Assignee: Hewlett-Packard Company
    Inventor: Mahmoud F. Abdel-Rahman
  • Patent number: 5773833
    Abstract: A photo-ionization detector (PID) which measures volatile organic gas uses electrically insulated parallel plates to energize a miniaturized gas discharge UV lamp and an energy efficient method to modulate the UV lamp intensity and reduce power consumption. A miniaturized centrifugal pump is integrated into the PID to provide active sampling for fast response to volatile gas. An ionization chamber in the PID includes a UV shield which protects a measurement electrode from UV light and a UV monitor which measures changes in UV intensity due to external interferences and UV lamp variations. A microprocessor in the PID uses measurements from the measurement electrode and from the UV monitor to accurately account for UV intensity variations when determining a volatile gas concentration.
    Type: Grant
    Filed: March 22, 1996
    Date of Patent: June 30, 1998
    Assignee: RAE Systems, Inc.
    Inventor: Peter C. Hsi
  • Patent number: 5760291
    Abstract: Electron capture detector for use with an effluent stream from a gas chromatograph includes an ionization chamber and a sample inlet system connected to the ionization chamber wherein the sample inlet system effects uniform fluid mixture of the effluent fluid and a make-up gas prior to entry of the fluid mixture into the ionization chamber. A preferred mixing device includes a column liner having a flow acceleration region wherein a localized reduction in the internal diameter of the liner causes momentary turbulence of the fluid mixture.
    Type: Grant
    Filed: September 3, 1996
    Date of Patent: June 2, 1998
    Assignee: Hewlett-Packard Co.
    Inventor: Mahmoud F. Abdel-Rahman
  • Patent number: 5679958
    Abstract: A beta radiation detector which is capable of reliably detecting beta radiation emitted from a surface. An electrically conductive signal collector is adjustably mounted inside an electrically conductive enclosure which may define a single large opening for placing against a surface. The adjustable mounting of the electrically conductive signal collector can be based on the distance from the surface or on the expected beta energy range. A voltage source is connected to the signal collector through an electrometer or other display means for creating an electric field between the signal collector and the enclosure. Air ions created by the beta radiation are collected and the current produced is indicated on the electrometer or other display means.
    Type: Grant
    Filed: February 27, 1996
    Date of Patent: October 21, 1997
    Assignee: The Regents of the University of California
    Inventor: Duncan W. MacArthur
  • Patent number: 5561344
    Abstract: A photo-ionization detector utilizes an ultraviolet (UV) lamp and is designed for detecting and measuring the concentration of volatile gases flowing between closely spaced parallel electrodes. One of the electrodes is formed to allow photons to pass into the space between the electrodes to ionize the volatile gases between the electrodes. The detector also incorporates an improved ionization chamber.
    Type: Grant
    Filed: March 7, 1995
    Date of Patent: October 1, 1996
    Assignee: RAE Systems, Inc.
    Inventor: Peter C. Hsi
  • Patent number: 5550381
    Abstract: An electrostatic detector for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: August 27, 1996
    Assignee: The Regents of the University California
    Inventors: Richard D. Bolton, Duncan W. MacArthur
  • Patent number: 5539208
    Abstract: A surface radiation detector for sensing low energy ionizing radiation on the surface of an object includes a open window gas proportional counter provided with a compressible skirt surrounding the window in a detection chamber. The compressible skirt is preferably of open cell plastic foam, but may be made from a gas impermeable sheet formed in the shape of an accordion bellows. An open screen of electrically conductive material, attached to said skirt and covering the window, may be placed in direct contact with the surface of an object to be tested. Counter gas flows at a rate into the chamber sufficient to maintain a positive pressure in the chamber relative to the ambient atmosphere. A momentarily actuated valve supplies additional counter gas at a flow rate sufficient to fill said chamber within a short period of time.
    Type: Grant
    Filed: January 27, 1995
    Date of Patent: July 23, 1996
    Inventor: Mario W. Overhoff
  • Patent number: 5393979
    Abstract: A photo-ionization detector utilizes an ultraviolet (UV) lamp for detecting and measuring the concentration of volatile gases flowing between closely spaced parallel electrodes. One of the electrodes is made of mesh to allow photons to pass into the space between the electrodes to ionize the volatile gases between the electrodes. The detector also incorporates an improved ionization chamber. In other embodiments, a plurality of gas discharge lamps, each generating a different photon energy, may be placed adjacent to a plurality of closely spaced electrodes, all electrodes in one ionization chamber, to detect and measure different types of volatile gases that may exist.
    Type: Grant
    Filed: May 12, 1993
    Date of Patent: February 28, 1995
    Assignee: RAE Systems, Inc.
    Inventor: Peter C. Hsi
  • Patent number: 5345083
    Abstract: An inner side of a radiation entrance window in an X-ray detector is provided with an electrically conductive layer of gold, platinum, irridium or a mixture of these elements. Using such a layer, suitable electrical conductivity, a low radiation absorption for soft X-rays and a suitable mechanical stability can be achieved also in the case of a comparatively small layer thickness.
    Type: Grant
    Filed: February 22, 1993
    Date of Patent: September 6, 1994
    Assignee: U.S. Philips Corporation
    Inventor: Johannes J. De Koning
  • Patent number: 5324948
    Abstract: An apparatus for conducting radiologic surveys. The apparatus comprises in the main a robot capable of following a preprogrammed path through an area, a radiation monitor adapted to receive input from a radiation detector assembly, ultrasonic transducers for navigation and collision avoidance, and an on-board computer system including an integrator for interfacing the radiation monitor and the robot. Front and rear bumpers are attached to the robot by bumper mounts. The robot may be equipped with memory boards for the collection and storage of radiation survey information. The on-board computer system is connected to a remote host computer via a UHF radio link. The apparatus is powered by a rechargeable 24-volt DC battery, and is stored at a docking station when not in use and/or for recharging.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: June 28, 1994
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Aed M. Dudar, David G. Wagner, Gregory D. Teese
  • Patent number: 5317159
    Abstract: An electron capture type detector for gas chromatography has an ionization vessel containing therein line sources for a radioactive isotope serving as a negative electrode, a collector electrode, a purge gas route, a discharge gas route, and an end of a column disposed at its lower section. The collector electrode includes a filament made of a heat resistant material and itself connected to a heating device such that the filament can be heated to about 300.degree.-600.degree. C. so as to eliminate contaminants deposited on the collector electrode by thermal decomposition, oxidation or reduction, without the necessity of disassembling the detector itself. The contaminants are effectively removed by simultaneously causing air or hydrogen gas to pass over the collector electrode through the ionization vessel from the purge gas route to the discharge gas route.
    Type: Grant
    Filed: November 20, 1992
    Date of Patent: May 31, 1994
    Assignee: Shimadzu Corporation
    Inventors: Toyoaki Fukushima, Shozo Tanabe
  • Patent number: 5298754
    Abstract: A substantially stable, substantially portable open-window gas flow Geiger-Mueller type detector capable of monitoring ionizing radiation having an electrically conductive chamber with one or more fluid inlets and opening to receive radiation. A counting gas is provided to the chamber through the inlet(s). The detector also has at least one insulated anode positioned in the chamber and a radiation permeable cover substantially sealed over the opening. A source of electricity is connected to the chamber and electric pulses generated within the chamber are detected when an ionizing event is caused by ionizing radiation entering the chamber.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: March 29, 1994
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Charles W. Anderson, John W. Nagy, Leonard R. Smith
  • Patent number: 5281824
    Abstract: A detector for atmospheric radon using a long range alpha detector as its sensing element. An electrostatic filter removes ions from ambient air, while allowing radon atoms to pass into a decay cavity. Here, radon atoms are allowed to decay, creating air ions. These air ions are drawn by a fan through a second electrostatic filter which can be activated or deactivated, and into the long range alpha detector. With the second electrostatic filter activated, no air ions are allowed to pass, and the signal output from the long range alpha detector consists of only the electronic background. With the second electrostatic filter deactivated, air ions and cosmic rays will be detected. The cosmic ray contribution can be minimized by shielding.
    Type: Grant
    Filed: April 7, 1992
    Date of Patent: January 25, 1994
    Assignee: The United States Department of Energy
    Inventors: Duncan W. MacArthur, Krag S. Allander, John A. Bounds
  • Patent number: 5254861
    Abstract: System and method for detection and measurement of airborne biological aerosol particles in a gaseous sample are described comprising a source of low energy radiation for irradiating the gaseous sample whereby biological particles in the sample are ionized, a detector for detecting ionized biological particles in the sample including a pair of electrically charged conducting plates disposed in parallel confronting relationship to each other with a preselected space therebetween, a source of electrical power operatively connected to the plates for applying a preselected electrical potential thereacross, and electronics for sensing collisions on the plates of ionized biological particles in the sample.
    Type: Grant
    Filed: September 29, 1992
    Date of Patent: October 19, 1993
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: David R. Carpenter, John Taboada
  • Patent number: 5194737
    Abstract: Alpha particle detectors capable of detecting alpha radiation from distant sources. In one embodiment, a voltage is generated in a single electrically conductive grid while a fan draws air containing air molecules ionized by alpha particles through an air passage and across the conductive grid. The current in the conductive grid can be detected and used for measurement or alarm. Another embodiment builds on this concept and provides an additional grid so that air ions of both polarities can be detected. The detector can be used in many applications, such as for pipe or duct, tank, or soil sample monitoring.
    Type: Grant
    Filed: October 8, 1991
    Date of Patent: March 16, 1993
    Assignee: University of California Patent, Trademark & Copyright Office
    Inventors: Duncan W. MacArthur, Krag S. Allander
  • Patent number: 5187370
    Abstract: An alpha particle detector, utilizing alternating currents, whcih is capable of detecting alpha particles from distinct sources. The use of alternating currents allows use of simpler ac circuits which, in turn, are not susceptible to dc error components. It also allows the benefit of gas gain, if desired. In the invention, a voltage source creates an electric field between two conductive grids, and between the grids and a conductive enclosure. Air containing air ions created by collision with alpha particles is drawn into the enclosure and detected. In some embodiments, the air flow into the enclosure is interrupted, creating an alternating flow of ions. In another embodiment, a modulated voltage is applied to the grid, also modulating the detection of ions.
    Type: Grant
    Filed: November 27, 1991
    Date of Patent: February 16, 1993
    Assignee: University of California
    Inventors: Duncan W. MacArthur, James L. McAtee
  • Patent number: 5126676
    Abstract: A gas-amplified ionization detector for gas chromatrography which possesses increased sensitivity and a very fast response time. Solutes eluding from a gas chromatographic column are ionized by UV photoionization of matter eluting therefrom. The detector is capable of generating easily measured voltage signals by gas amplification/multiplication of electron products resulting from the UV photoionization of at least a portion of each solute passing through the detector.
    Type: Grant
    Filed: November 27, 1989
    Date of Patent: June 30, 1992
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Gregg C. Huston
  • Patent number: 5028544
    Abstract: The objects of the invention are attained in an apparatus for performing a method of analysis of organic compounds in chromatography, comprising a chromatographic column sealingly connected with the housing of a surface ionization detector having coaxially arranged inside, a collector and a thermoemitter with current leads, the housing of the surface ionization detector being provided with an opening for an auxiliary gas feed line and an opening for delivering the spent gases. The thermoemitter includes a closed-end sleeve with a heating element in contact with the external non-working surface of the thermoemitter. The collector includes a hollow cylinder spaced from the inner ionizing surface of the thermoemitter, and the outlet portion of the chromatographic column being received inside and throughout the length of the collector.
    Type: Grant
    Filed: October 14, 1988
    Date of Patent: July 2, 1991
    Inventors: Utkur K. Rasulev, Erkinzhan G. Nazarov, Valery O. Sidelnikov, Rustam N. Evtukhov, Shavkat S. Alimkhodzhaev, Bakhtiyar M. Tashpulatov, Gulsara B. Khudaeva
  • Patent number: 4990786
    Abstract: The Alpha Energy Range Discrimination (AERD) method employs first and second proportional counter tubes separated by a foil and an electronic evaluation system, and comprises the following steps:(a) a filter is disposed in the stream of air flow and is thereby covered with dust, no artificial aerosol alpha activity being present;(b) the radiation of natural nuclides is measured by means of the first and second counter tubes in pulses per second, and respective count rates alpha.sub.1 and alpha.sub.2 are determined;(c) the ratio alpha.sub.1 /alpha.sub.2 is plotted graphically against alpha.sub.2 and corresponding constant values a.sub.1 and a.sub.2 are determined for each counter tube in accordance with the least square fit method;(d) the counter tubes are arranged with the second counter tube above the first counter tube, separated by the separating foil, so that the lower counter tube measures the radiation of both natural and artificial nuclides (count rate alpha.sub.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: February 5, 1991
    Assignee: FAG Kugelfischer Georg Schafer (KGaA)
    Inventors: Hans-Jurg Kreiner, Eberhard Frenzel
  • Patent number: 4880983
    Abstract: A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: November 14, 1989
    Assignee: Yale University
    Inventor: John K. Markey
  • Patent number: 4879472
    Abstract: Method and apparatus for detecting and differentiating organic compounds based on their electron affinity. An electron capture detector cell (ECD) is operated in a plurality of multiplexed electroncially programmable operating modes to alter the detector response during a single sampling cycle to acquire multiple simultaneous chromatograms corresponding to each of the different operating modes. The cell is held at a constant subatmospheric pressure while the electron collection bias voltage applied to the cell is modulated electronically to allow acquisition of multiple chromatograms for a single sample elution from a chromatograph representing three distinctly different response modes.
    Type: Grant
    Filed: May 19, 1988
    Date of Patent: November 7, 1989
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Marcus B. Wise, Michelle V. Buchanan
  • Patent number: 4870281
    Abstract: The anode connections in a gas-filled X-ray detector are mounted so as to extend transversely of the anode wire so that a substantial saving as regards space is achieved. In order to reduce field inhomogeneities in the ionization space, there may be provided a field profile bush which partly encloses the anode wire and field bushes may be arranged around the anode connection pins.
    Type: Grant
    Filed: February 4, 1988
    Date of Patent: September 26, 1989
    Assignee: U.S. Philips Corporation
    Inventors: Johannes Van Der Borst, Lourens Valkonet, Frans G. Vreugdenhil
  • Patent number: 4862005
    Abstract: An apparatus for detecting radioactive contamination in hand-held objects, such as tools used to service a nuclear power facility, is disclosed herein. The apparatus generally comprises a radiation detector assembly having a gas-flow proportional detector, and a platform assembly formed from a perforated sheet of rigid material disposed over the topside of the detector for both supporting the hand-holdable objects and uniformly spacing the object from the detector. The radiation detector assembly is contained within a shielding cabinet having an access opening that is offset out of alignment with the top side of the detector for allowing an operator to deposit and withdraw an object onto and off of the platform. The walls of the shielding cabinet include pocket-like mounting assemblies for releasably holding one or more sheets of lead shielding material so that the amount of background radiation-reducing shielding may be advantageously adjusted.
    Type: Grant
    Filed: June 2, 1988
    Date of Patent: August 29, 1989
    Assignee: Westinghouse Electric Corp.
    Inventors: Alfred N. Johnson, Martin D. Humphrey
  • Patent number: 4837440
    Abstract: Aerosol particles, resulting from the combustion of organic substances with insufficient oxygen supply, usually contain toxic, higher hydrocarbonic substances (e.g. tar) on their surface. These substances, e.g. tar, has the property to be photoelectrically more active than other substances contained in the atmosphere. In the method and apparatus according to the invention an aerosol, i.e. the carrier gas containing the particles to be characterized, is used which has been brought to at least one predetermined temperature sufficient for evaporation or decomposition or preventing condensation of molecules on particles of said aerosol that quench or enhance photoelectric activity. Such aerosol is exposed to electromagnetic radiation and, thereby, activated to electron emission. Thereafter the charge of the photoelectrically positively charged particles is determined by means of size selective filter means which are connected to current or charge measuring equipment.
    Type: Grant
    Filed: November 3, 1986
    Date of Patent: June 6, 1989
    Assignee: Matter & Siegmann AG
    Inventors: Heinz Burtscher, Adnreas Schmidt-Otl, Hans-Christoph Siegmann