With Indicating Or Recording Means Patents (Class 250/392)
  • Patent number: 10650932
    Abstract: A detector signal-processing circuit comprises the following: a current/voltage conversion part that converts the current value of a neutron detector to a voltage value; a variable gain amplification part that performs amplification by a first-step variable gain using a D/A converter; a current level response-use resistance circuit that selects the measurement range in accordance with the voltage value; temperature measurement units for measuring the temperature of the resistance circuit for current level response; a temperature compensation part for commanding gain compensation by the D/A converter on the basis of the measured temperature; and a selective adjustment control part for selective control of the measurement range and adjustment of the variable gain of the variable gain amplification part. Due to this configuration, neutron flux can be measured with high precision while maintaining a constant output precision, before and after switching of the measurement range.
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: May 12, 2020
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Toshihide Aiba, Toshimitsu Nakai
  • Patent number: 10317559
    Abstract: A ground tracking apparatus for connection to a locator or other measurement device and configured to determine position, motion, and/or orientation information is disclosed. The ground tracking apparatus may include a ground follower assembly including one or more wheels, which may be detachably coupled to a buried object locator system to capture three-dimensional positional and orientation information during a locate process, as well as provide output data or information to be integrated with maps, photographs, drawings, or other data or information.
    Type: Grant
    Filed: June 26, 2017
    Date of Patent: June 11, 2019
    Assignee: SEESCAN, INC.
    Inventors: Mark S. Olsson, David A. Cox, Ryan B. Levin, Ray Merewether, Sequoyah Aldridge
  • Patent number: 10061056
    Abstract: Various embodiments include apparatus and methods to conduct measurements on a formation using a dual purpose detector. The dual purpose detector can be disposed on a neutron tool in a borehole, where the dual purpose detector operatively detects neutrons and gamma rays in response to the formation being probed using a neutron source of the neutron tool. Porosity of the formation can be determined from data based on the neutrons and gamma rays detected by the dual purpose detector. Additional apparatus, systems, and methods are disclosed.
    Type: Grant
    Filed: May 30, 2013
    Date of Patent: August 28, 2018
    Assignee: HALLIBURTON ENERGY SERVICES, INC.
    Inventor: Gordon L. Moake
  • Patent number: 9796921
    Abstract: The present disclosure is directed to liquid boron compounds for use in scintillation. The present disclosure further relates to liquid boron compounds for admixture to plastic and liquid scintillators.
    Type: Grant
    Filed: August 5, 2014
    Date of Patent: October 24, 2017
    Assignee: Colorado School of Mines
    Inventors: Cory Pecinovsky, Pascale Meysing, Adam Mahl, John Dorgan, Uwe Greife, Tyler Remedes
  • Patent number: 9702988
    Abstract: A method for detecting both gamma-ray events and neutron events with a common detector, where the detector includes a layer of semiconductor material adjacent one side of a glass plate and a Gd layer on an opposite side of the glass plate, between the glass plate and a layer of silicon PIN material to form an assembly that is bounded by electrodes, including a semiconductor anode on one side of the semiconductor layer, a cathode connected to the glass plate, and a Si PIN anode on a side of the Si PIN layer opposite the semiconductor anode. The method includes the steps of: (1) monitoring the electrical signal at each of the semiconductor anode and the Si PIN anode, and (2) comparing signals from the semiconductor anode and the SI PIN anode to differentiate between gamma-ray events and neutron events based on predetermined criteria.
    Type: Grant
    Filed: January 6, 2016
    Date of Patent: July 11, 2017
    Assignee: Raytheon Company
    Inventors: David R Rhiger, Justin Gordon Adams Wehner, Kelly Jones, Siddhartha Ghosh
  • Patent number: 9046613
    Abstract: A radiation detector for neutrons and gamma-rays includes a conversion screen comprising a mixture of a neutron absorbing material, e.g., containing 6Li, and a phosphorescent material, e.g., ZnS(Ag) and a wavelength-shifting light-guide arranged to receive photons emitted from the phosphorescent material and generate wavelength-shifted photons therefrom. The wavelength-shifting light-guide is doped so as to form a gamma-ray scintillator material operable to generate scintillation photons in response to a gamma-ray detection event therein. A photodetector is optically coupled to the wavelength-shifting light-guide and arranged to detect the wavelength-shifted photons and the scintillation photons. Signals from the photodetector are processed to distinguish neutron detection events from gamma-ray detection events.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: June 2, 2015
    Assignee: Symetrica Limited
    Inventors: David Ramsden, Calvin Giles
  • Publication number: 20140361186
    Abstract: The invention relates to an improved method for detecting and possibly identifying and/or characterizing nuclear and/or radiological material in a container, vehicle, or on a person, comprising the steps of: a. providing at least one detector, which is capable of detecting radiation events being interrelated to nuclear or radiological material; b. bringing the at least one detector in the vicinity of the container, vehicle or person to be monitored; c. detecting radiation events being interrelated to the container, vehicle or person to be monitored; d. assigning each detected radiation event an individual time stamp in order to generate a time pattern of the detected radiation events; and e. analyzing the time pattern with respect to time correlation structures in order to identify a presence and/or characteristics of the nuclear or radiological material.
    Type: Application
    Filed: June 10, 2013
    Publication date: December 11, 2014
    Inventors: Rico Chandrasekharan, David Murer, Ulisse Gendotti, Giovanna Davatz
  • Patent number: 8858831
    Abstract: Scintillator compositions are provided which include a solvent or matrix containing a fluorophore having the formula (I) and/or a fluorophore having the formula (II), wherein R1 and R2, being identical or different, are independently chosen from the group consisting of hydrogen, halogen, alkyl which optionally contains one or more heteroatoms, alkoxy, aryl and alkyne with an aryl end group; R3 is chosen from the group consisting of hydrogen, alkyl which optionally contains one or more heteroatoms, aryl, heterocycle, ether and ester; R4 and R5, being identical or different, are independently chosen from the group consisting of hydrogen, alkyl which optionally contains one or more heteroatoms, aryl, heterocycle, ether and ester, whereby the R4 and R5 groups are optionally combined to one cyclic structure; and R6, if present, is chosen from the group consisting of hydrogen, aryl and alkyl.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: October 14, 2014
    Assignee: Stichting Incas3
    Inventors: Peter Dijkstra, Heinrich Johannes W├Ârtche
  • Patent number: 8502157
    Abstract: A neutron detector includes an exterior shell bounding an interior volume. The neutron detector includes at least a wall portion serving as a cathode. In one example the wall portion has microfeatures. The neutron detector includes a central structure located within the interior volume and serving as an anode. The neutron detector includes a boron coating on the wall portion. In on example, the boron coating is applied by an electrostatic spray process. In one example, the boron coating conforms to the microfeatures on the wall portion. In one example, the wall portion has a thickness of between 2 to 5 microns. The neutron detector includes an electrical connector operatively connected to the central structure for transmission of a signal collected by the central structure. An associated method provides for depositing the boron coating.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: August 6, 2013
    Assignee: General Electric Company
    Inventors: James Michael Lustig, Jon Bennett Jansma
  • Publication number: 20130062531
    Abstract: A neutron detector includes an exterior shell bounding an interior volume. The neutron detector includes at least a wall portion serving as a cathode. In one example the wall portion has microfeatures. The neutron detector includes a central structure located within the interior volume and serving as an anode. The neutron detector includes a boron coating on the wall portion. In on example, the boron coating is applied by an electrostatic spray process. In one example, the boron coating conforms to the microfeatures on the wall portion. In one example, the wall portion has a thickness of between 2 to 5 microns. The neutron detector includes an electrical connector operatively connected to the central structure for transmission of a signal collected by the central structure. An associated method provides for depositing the boron coating.
    Type: Application
    Filed: September 9, 2011
    Publication date: March 14, 2013
    Applicant: General Electric Company
    Inventors: James Michael Lustig, Jon Bennett Jansma
  • Publication number: 20130043379
    Abstract: Each pulse of a pulse sequence received from a neutron detector is set as a trigger pulse triggering a predefined gate, the multiplicity of pulses within this gate is determined, the pulse having triggered the gate is assigned to a multiplicity category corresponding to this multiplicity of pulses and the trigger-to-predecessor distances from the trigger pulse to pulses preceding the trigger pulse within a certain range in the pulse sequence are determined. The range within which one looks for predecessor pulses of each trigger pulse exceeds the dead time of the neutron detector. For each multiplicity category, the number of trigger pulses assigned thereto is determined. For each multiplicity category, one builds, based upon the trigger-to-predecessor intervals determined, a distribution in time after an arbitrary preceding pulse of trigger pulses assigned to that specific multiplicity category.
    Type: Application
    Filed: July 9, 2010
    Publication date: February 21, 2013
    Applicant: The European Atomic Energy Community(EURATOM)
    Inventors: Ludwig Holzleitner, Martyn T. Swinhoe
  • Patent number: 8299439
    Abstract: A method of operating a radiation-detecting device includes charging a first charge storage region of a charge storage structure to place a first charge value at the first charge storage region, and charging a second charge storage region of the charge storage structure to place a second charge value at the second charge storage region. The method further includes conducting a first read operation to determine a change in the first charge value at the first charge storage region at a first time after charging the first charge storage region, and determining a first radiation flux value for an environment containing the charge storage structure based on the change in the first charge value at the first time.
    Type: Grant
    Filed: May 19, 2009
    Date of Patent: October 30, 2012
    Assignee: Spansion LLC
    Inventor: Michael McCarthy
  • Publication number: 20120043469
    Abstract: A radiation detecting device is provided, according to which it is possible use only one radiation detecting device to measure radiation and measure gamma ray and neutron at once and discriminately in a restricted space. The radiation detecting device includes a radiation detecting unit to measure gamma ray and neutron discriminately at once, and a signal processing circuit which applies voltage to the neutron detecting unit and indicates measured gamma ray and neutron discriminately.
    Type: Application
    Filed: July 25, 2011
    Publication date: February 23, 2012
    Applicants: Korea Hydro and Nuclear Power Co., Ltd., Korea Atomic Energy Research Institute
    Inventors: Se-Hwan Park, Sung-Ho Eom, Hee-Sung Shin, Han Soo Kim, Ha-Dong Kim
  • Patent number: 8115179
    Abstract: A preamplifier circuit for processing a signal provided by a radiation detector includes a transimpedance amplifier coupled to receive a current signal from a detector and generate a voltage signal at its output. A second amplification stage has an input coupled to an output of the transimpedance amplifier for providing an amplified voltage signal. Detector electronics include a preamplifier circuit having a first and second transimpedance amplifier coupled to receive a current signal from a first and second location on a detector, respectively, and generate a first and second voltage signal at respective outputs. A second amplification stage has an input coupled to an output of the transimpedance amplifiers for amplifying the first and said second voltage signals to provide first and second amplified voltage signals.
    Type: Grant
    Filed: September 15, 2010
    Date of Patent: February 14, 2012
    Assignee: UT-Battelle
    Inventors: Richard A. Riedel, Alan L. Wintenberg, Lloyd G. Clonts, Ronald G. Cooper
  • Publication number: 20110042577
    Abstract: A detector for fast neutrons has been developed which includes 1) selected open structure of solid hydrogen-containing material which converts impinging neutrons into recoil protons; 2) a surrounding gas which interacts with the protons to release electrons; 3) an electric field able to drift the electrons through and away from the open-structure material; and 4) an electron detector which monitors the drifted electrons thereby sensing the original impinging neutrons. This type of detector is advantageous for many applications, including efficient fast neutron detection; large area imaging of fast neutrons for fast neutron radiography; or fast neutron beam profiling.
    Type: Application
    Filed: August 19, 2010
    Publication date: February 24, 2011
    Inventors: HUGH ROBERT ANDREWS, Marius Emanuel Facina, Harry Ing, Vernon Theodore Koslowsky, Vitali Dmitrievitch Kovaltchouk, Irina Stefanescu
  • Publication number: 20110001055
    Abstract: A preamplifier circuit for processing a signal provided by a radiation detector includes a transimpedance amplifier coupled to receive a current signal from a detector and generate a voltage signal at its output. A second amplification stage has an input coupled to an output of the transimpedance amplifier for providing an amplified voltage signal. Detector electronics include a preamplifier circuit having a first and second transimpedance amplifier coupled to receive a current signal from a first and second location on a detector, respectively, and generate a first and second voltage signal at respective outputs. A second amplification stage has an input coupled to an output of the transimpedance amplifiers for amplifying the first and said second voltage signals to provide first and second amplified voltage signals.
    Type: Application
    Filed: September 15, 2010
    Publication date: January 6, 2011
    Applicant: UT-Battelle, LLC
    Inventors: Richard A. Riedel, Alan L. Wintenberg, Lloyd G. Clonts, Ronald G. Cooper
  • Publication number: 20090321650
    Abstract: A radiation detection blanket for use in surveying a broad or irregular area of interest for radiation emissions. Small radiation detectors are affixed to the fabric and distributed relative to its surface area. The detector materials may be of the OSL, TLD, or ERD variety, or may be a combination of OSL, TLD and ERD. Detector materials having varying thicknesses of high Z coatings may be clustered together in the blanket fabric to yield a gamma radiation spectrum. Use of a converter material on the detector material allows the blanket to detect neutron radiation. The blanket includes specialized transmission means for allowing the detector materials to be read individually, by passing the reader along a surface or along an edge of the blanket. A composite radiation measurement is obtained upon reading the individual detectors, allowing determination of the radiation distribution within the object being surveyed by the blanket.
    Type: Application
    Filed: April 22, 2008
    Publication date: December 31, 2009
    Inventors: Steven P. Kadner, Markku J. Koskelo, Robert Craig Yoder
  • Publication number: 20090166550
    Abstract: Neutron detectors including one or more gamma shields over memory dies and methods of making the neutron detectors are provided. The neutron detectors can contain two or more memory dies, neutron-reactant layers over the two or more memory dies, and one or more gamma shields over at least a portion of or an entire of the two or more memory dies. By containing the gamma shield over the at least a portion of or an entire of the two or more memory dies, the neutron detector can detect and discriminate neutrons in the presence of gamma rays.
    Type: Application
    Filed: December 28, 2007
    Publication date: July 2, 2009
    Applicant: SPANSION LLC
    Inventors: Jerzy Gazda, Tim Z. Hossain
  • Patent number: 7505544
    Abstract: A system for detecting and classifying small amounts of explosives and other controlled substances while rejecting confounders, including a source/detector array formed of a plurality of sources and a plurality of detectors, a signal processor coupled to the source/detector array for processing data received from the detectors, a classifier coupled to the signal processor for classifying data received from the signal processor according to a plurality of algorithms, a maximal rejection classifier coupled to the classifier; and a declarative decision module coupled to the maximal rejection classifier for rendering an accurate decision regarding the contents of the object is provided. The apparatus includes an enclosure, a shield layer disposed within the enclosure, a cavity disposed within the shield layer, a plurality of neutron sources and a detection array disposed within the cavity, and a transport mechanism for moving objects through the cavity past the sources and detection array.
    Type: Grant
    Filed: January 9, 2004
    Date of Patent: March 17, 2009
    Assignee: FAJ International Holdings, LLC
    Inventor: Aaron L. Jestice
  • Publication number: 20080272308
    Abstract: A detector is provided that includes a plurality of layered hemispherically shaped elements. Each element is configured to sense the detection of an event. The detector further includes a lead for each element. Each lead is configured to pass a detection signal when its associate element detects an event.
    Type: Application
    Filed: May 1, 2007
    Publication date: November 6, 2008
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventor: John R. Samson, Jr.
  • Patent number: 7235784
    Abstract: Drift generated at the time of photographing a TEM image is corrected simultaneously with photographing, so that a TEM image free form influence of drift is photographed. While the TEM image is recorded, drift in the place out of the view field subjected to recording is measured from moment to moment by another TV camera or a position sensitive detector. Drift is corrected by the movement of the specimen due to a specimen holder or by the movement of the image due to an image shift coil.
    Type: Grant
    Filed: October 7, 2005
    Date of Patent: June 26, 2007
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Yoshifumi Taniguchi, Hisafumi Otsuka
  • Patent number: 7026627
    Abstract: A portable survey instrument and methodology yield intensity of neutron radiation, intensity of gamma radiation, and a direction of impinging gamma radiation. The instrument uses a neutron detector surrounded by an essentially rectangular moderator with preferably four gamma ray detectors disposed symmetrically about the neutron detector and within the moderator. Material and dimensions of the moderator are selected so that the neutron measurement is equally sensitive to fast and thermal neutrons. The moderator also induces angular responses to the gamma ray detectors. Responses of the gamma ray detectors are combined to yield a parameter indicative of the angular position of a source. The survey instrument is portable and suited for hand held use.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: April 11, 2006
    Assignee: Delta Epsilon Instruments
    Inventors: Fred E. Fowler, Jr., Jerry L. Burnham, Robert D. Wilson
  • Patent number: 6838671
    Abstract: A device and method for detection of buried objects (40) utilizing a down looking infrared array (140) having infrared detectors (170) positioned in a sensor array (30). This sensor array (30) may also contain ground penetrating radar (70) and EMI coils (80). All signals from the ground penetrating radar (70), EMI coils (80) and down looking infrared array (140) may be combined to generate alarms (1100). However, the down looking infrared array (140) may be utilized as a sole means of detecting buried objects (40). This device and method for detecting buried objects (40) utilizing down looking infrared array (140) reduces the cost of construction and maintenance of such a device.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: January 4, 2005
    Assignee: Northrop Grumman Corporation
    Inventors: Stephen B. Compana, Conrad W. Terrill
  • Patent number: 6577697
    Abstract: A system and method for rapidly analyzing elemental abundances in rock or soil samples (14) under field conditions. The system uses a portable neutron source (12) to allow neutron activation analysis of elements having identifiable radioactive decay characteristics. A radiation detector (18) detects radiation released by the sample (14) and provides radiation testing results to an amplifier (26) for computing the concentration of trace elements in the sample with a high degree of accuracy.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: June 10, 2003
    Assignee: Southwest Research Institute
    Inventors: English C. Pearcy, Mark S. Jarzemba, James R. Weldy
  • Patent number: 6529573
    Abstract: A neutron rem meter utilizing proton recoil and thermal neutron scintillators to provide neutron detection and dose measurement. In using both fast scintillators and a thermal neutron scintillator the meter provides a wide range of sensitivity, uniform directional response, and uniform dose response. The scintillators output light to a photomultiplier tube that produces an electrical signal to an external neutron counter.
    Type: Grant
    Filed: March 9, 2001
    Date of Patent: March 4, 2003
    Assignee: The Regents of the University of California
    Inventors: Richard H. Olsher, David T. Seagraves
  • Patent number: 6456681
    Abstract: A neutron flux measuring apparatus, adapted to a boiling-water reactor (BWR) of a nuclear power plant and an advanced boiling-water reactor (ABWR) of a nuclear power plant, for measuring a neutron flux in a reactor pressure vessel, comprises a neutron flux detector assembly incorporating a local power range monitor detector assembly and a start-up range neutron monitor detector, a preamplifier amplifying a detector signal obtained from said start-up range neutron monitor detector, a start-up range neutron monitor operation unit operating, indicating and monitoring the amplified signal of the start-up range neutron monitor detector, and a local power range monitor operation unit operating, indicating and monitoring a signal obtained from the local power range monitor detector.
    Type: Grant
    Filed: August 31, 1999
    Date of Patent: September 24, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasushi Goto, Nobuaki Oono, Yuki Narawa, Teruji Tarumi, Koji Hirukawa
  • Patent number: 6333631
    Abstract: Apparatus and method is provided for performing detailed mine detection over variable terrain. An articulated robotic scanner comprises an articulated arm mounted to any vehicle such as a robot. One or more mine detectors mounted at the end of the arm. The arm operates autonomously to repetitively sweep the mine detector in ever forward advancing side-to-side arcs over the terrain. The vehicle can operate autonomously or be tele-operated. The position of the mine detector is monitored and known with respect to a known coordinate system. Sensors measure their position relative to the ground and relative to known co-ordinates of the mine detector. A controller determines the relative position of the ground and the mine detector and dynamically adjusts the mine detector's position to maintain a constant separation over variable terrain without ever contacting the ground or objects thereon.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: December 25, 2001
    Assignee: Minister of National Defence of Her Majesty's Canadian Government
    Inventors: Yogadish Das, Kevin Russell, Nenad Kircanski, Andrew Goldenberg
  • Patent number: 6026135
    Abstract: A multisensor vehicle-mounted mine detector having one or more sensors leading the vehicle for detecting objects in the ground while moving. A navigational system tracks the coordinates of the detected objects, performs data fusion, declares whether the object is a target worthy of interest and if so, stops the vehicle with a trailing thermal neutron activator sensor (TNA) over the coordinates of the object and interrogating the object with slow neutrons to confirm whether it contains sufficient nitrogen to indeed be a mine. The TNA confirmation is kept brief due to the use of a strong source coupled with means for analysing the resultant pulses and rejecting piled-up pulses. The difference between an integration of the entire pulse and a portion of the pulse is compared against a predetermined difference for a normal pulse wherein variations therebetween are indicative of a piled-up pulse which is then rejected.
    Type: Grant
    Filed: April 3, 1998
    Date of Patent: February 15, 2000
    Assignee: Her Majesty the Queen in right of Canada, as represented by the Minister of National Defence of Her Majesty's Canadian Government
    Inventors: John E. McFee, Victor C. Aitken, Yogadhish Das, Kevin L. Russell, Chris A. Brosinsky, Robert H. Chesney, Philip Church, George Gundesen, Edward T. H. Clifford, E. Barclay Selkirk, Harry Ing, Robert O. Ellingson, Steven G. Penzes, Mick Saruwatari, Kevin Saruwatari, Craig Poulsom
  • Patent number: 5818054
    Abstract: A method and apparatus for non-invasively determining the internal composition of objects are disclosed. The object of interest is probed with low energy, monoenergetic narrow beams of fast neutrons. The object is generally placed on a conveyor belt which is positioned between the accelerator and the detectors. Detectors, positioned at radial angles corresponding to the resonance energy levels of certain preselected elements, measure the neutrons that are not absorbed or scattered by the elements in the object and thus pass straight through the object. The information obtained from the detectors can then be used for subsequent tomographic reconstruction.
    Type: Grant
    Filed: April 29, 1997
    Date of Patent: October 6, 1998
    Assignee: Radio Programmes Corp.
    Inventors: Gerhard Randers-Pehrson, David Brenner
  • Patent number: 5578830
    Abstract: A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: November 26, 1996
    Assignee: The Regents of the University of California
    Inventors: Richard H. Olsher, Hsiao-Hua Hsu, William H. Casson, Dennis G. Vasilik, Jeffrey H. Kleck, Anthony Beverding
  • Patent number: 5567936
    Abstract: A reference locket for use in calibrating a radiac computer indicator or trument having a light emitting diode or LED. The present invention is an inexpensive stable device having a base, a retainer placed in the base holding a light emitting diode or LED, and a cover forming a reference locket. The reference locket is placed in a radiac computer indicator or instrument for calibration. A forward constant current pulse provided to the LED results in electromagnetic radiation or light that simulates a gamma dose. The characteristic junction resistance of the LED simulates a neutron reading. The present invention replaces a conventional reference locket having a silver activated phosphate glass and a neutron diode. The phosphate glass blocks have exhibited unexplained increases in the previously calibrated gamma doses. Therefore, calibration or reference lockets using phosphate glass may be unstable.
    Type: Grant
    Filed: June 23, 1995
    Date of Patent: October 22, 1996
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Michael J. Basso
  • Patent number: 5557108
    Abstract: An apparatus and method for non-destructively detecting and identifying narcotics, explosives, and other forms of contraband concealed within a container or otherwise hidden from view. A radioactive source is used in conjunction with both neutron and gamma ray detector arrays. Depending upon the desired accuracy as well as the accessibility to all sides of the container, both back scattered and forward scattered radiation can be measured. Multiple detection systems mounted along different axes allow pseudo three dimensional images of the container in question as well as its contents to be produced.
    Type: Grant
    Filed: June 15, 1995
    Date of Patent: September 17, 1996
    Inventor: Tumay O. Tumer
  • Patent number: 5446288
    Abstract: A portable device used for non-destructive detection of illicit narcotics, or other hydrogen or light element containing substances, includes a weak, self-contained, radioactive source of fast neutrons and a detector for detecting scattered thermal neutrons and gamma rays. The detector design allows it to detect hermetically sealed or unsealed packages of narcotics or other materials concealed behind compartment barriers. The detector can also be used to detect the identity or type of material by simultaneously using both the gamma ray flux and thermal neutrons flux.
    Type: Grant
    Filed: October 25, 1993
    Date of Patent: August 29, 1995
    Inventor: Tumay O. Tumer
  • Patent number: 5278417
    Abstract: A device for measuring dose equivalents in neutron radiation fields. The device includes nested symmetrical hemispheres (forming spheres) of different neutron moderating materials that allow the measurement of dose equivalents from 0.025 eV to past 1 GeV. The layers of moderating material surround a spherical neutron counter. The neutron counter is connected by an electrical cable to an electrical sensing means which interprets the signal from the neutron counter in the center of the moderating spheres. The spherical shape of the device allows for accurate measurement of dose equivalents regardless of its positioning.
    Type: Grant
    Filed: November 25, 1992
    Date of Patent: January 11, 1994
    Assignee: The Regents of the University of California
    Inventor: Rai Ko S.F. Sun
  • Patent number: 5229066
    Abstract: The present invention is a system which determines nuclear reactor control rod axial position using a deviation signature database generated from a current or reference signal pattern produced by one or more strings of axially dispersed fixed incore detector sections in the reactor core. The deviation signature database is produced by assuming deviant axial positions for the control rods in the core, calculating expected detector signals for the assumed positions and storing the deviation of expected signals from a calibration reference along with corresponding assumed rod positions. The signature database is periodically updated to take into account changed core conditions. When a change in detector responses is detected the system performs a signature analysis of the deviations in the signature database using the current deviation from the reference to search for the closest match.
    Type: Grant
    Filed: August 5, 1991
    Date of Patent: July 20, 1993
    Assignee: Westinghouse Electric Corp.
    Inventors: Albert J. Impink, Jr., Michael D. Heibel, Louis R. Grobmyer
  • Patent number: 5192490
    Abstract: A neutron detection device is housed in a metal enclosure containing a first detector with a high-sensitivity fission chamber, and a second detector having a low-sensitivity fission chamber and a boron-lined ionization chamber compensated for gamma radiation. The detection device is useful for extended range measurement of the neutron fluence rate outside the core of a nuclear reactor.
    Type: Grant
    Filed: November 27, 1991
    Date of Patent: March 9, 1993
    Assignee: Merlin Gerin
    Inventor: Jean-Pierre Burel
  • Patent number: 5180917
    Abstract: The invention relates to a method and an apparatus for qualifying the operation of a radiation (e.g. neutron) detector containing an ionizable gas (e.g. He.sub.3), such as a detector disposed in a logging sonde designed to be lowered in a well, wherein a radioactive source capable of ionizing said gas is disposed inside the detector. From the counts of the ionization pulses, one qualifies the operation of the detector. The method provides either a verification (usually performed before the logging operation, outside the well) or, when carried out while the detector is operating in the well, a stabilization of the measured spectrum.Preferably, the internal source is an alpha source comprising uranium or americium and which is disposed inside the detector in the form of a thin foil.
    Type: Grant
    Filed: September 4, 1991
    Date of Patent: January 19, 1993
    Assignee: Schlumberger Technology Corporation
    Inventor: Peter D. Wraight
  • Patent number: 5155356
    Abstract: An apparatus and method for detecting changes in a physical property of the material beneath a large storage vessel, such as a landfill. The apparatus includes one or more tubes defining elongate channels in the material beneath the storage vessel. A sensing probe is moved through the channel while taking and collecting measurements of the physical property of the material in the vicinity of the probe. Typically, moisture and/or density may be measured using conventional nuclear sources and associated detectors. The measurements are compared with reference data to thereby detect a change indicating a leak in the storage vessel.
    Type: Grant
    Filed: November 29, 1991
    Date of Patent: October 13, 1992
    Assignee: Troxler Electronic Laboratories, Inc.
    Inventors: Lawrence E. Peters, Ali Regimand
  • Patent number: 5078951
    Abstract: A high-efficiency apparatus for detecting fast neutrons includes an assembly of disks of solid state charged particle detector material, or other appropriate charged particle detecting devices, disposed between adjacent thick (on the order of 1 mm) disks of fissionable material. The fissionable material must be an isotope that has a sharp increase in the neutron-induced fission cross section at a neutron energy of about 100 keV or greater, i.e., a fast neutron. An array of such assemblies housed in a thermal neutron shielding structure provides a threshold detector for fast neutrons resulting from neutron-induced fission of the fissionable material.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: January 7, 1992
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Robert A. August, Jr.
  • Patent number: 5057268
    Abstract: Paper notes used as a monetary currency are deuterated. The level of deuteration while not complete, is high. For U.S. currency the level of deuteration is at least 0.1 mg of deuterium for each one dollar in value of the currency note, and preferably at least 0.3 mg. Use of X-ray or gamma ray interrogation with a beam energy above 2 MeV produces a nuclear reaction releasing a neutron from the deuterium nucleus. If the currency is in large concentrations, e.g. $100,000 or more, the neutrons emitted by this reaction are reliably detectable. The deuteration occurs in the cellulose fibers forming the currency. To resist an exchange of hydrogen atoms for deterium atoms, the deuterium atoms can be used in the formation of synthetic cellulose where the deuterium is more deeply buried within the cellulose molecule than in naturally occurring cellulose. The deuterated synthetic fibers are blended with natural, non-deuterated fibers to form the paper.
    Type: Grant
    Filed: December 19, 1990
    Date of Patent: October 15, 1991
    Assignee: The Mitre Corporation
    Inventor: Richard A. Muller
  • Patent number: 4853174
    Abstract: A method and apparatus for monitoring the neutron flux in the core of a nuclear reactor by means of a neutron detector which is composed of two electrodes between which a d.c. bias voltage is applied and which has a greater neutron sensitivity when the d.c. bias voltage is applied with one polarity than with the opposite polarity, which involves operating the nuclear reactor at a power level in the vicinity of zero, and applying a d.c. bias level with the one polarity between the detector electrodes and measuring the neutron-induced current flowing through the detector electrodes.To permit reversal of the bias voltage polarity, a safety interlock is provided to permit this to occur only if the bias voltage has been brought below a selected level.
    Type: Grant
    Filed: October 6, 1987
    Date of Patent: August 1, 1989
    Assignee: Westinghouse Electric Corp.
    Inventors: Fred H. Bednar, Kenneth G. Lunz
  • Patent number: 4814623
    Abstract: A pulsed neutron detector and system for detecting low intensity fast neutron pulses has a body of beryllium adjacent a body of hydrogenous material the latter of which acts as a beta particle detector, scintillator, and moderator. The fast neutrons (defined as having En>1.5 MeV) react in the beryllium and the hydrogenous material to produce larger numbers of slow neutrons than would be generated in the beryllium itself and which in the beryllium generate hellium-6 which decays and yields beta particles. The beta particles reach the hydrogenous material which scintillates to yield light of intensity related to the number of fast neutrons. A photomultiplier adjacent the hydrogenous material (scintillator) senses the light emission from the scintillator. Utilization means, such as a summing device, sums the pulses from the photo-multiplier for monitoring or other purposes.
    Type: Grant
    Filed: April 22, 1987
    Date of Patent: March 21, 1989
    Assignee: University of New Mexico
    Inventors: J. Craig Robertson, deceased, Mark S. Rowland
  • Patent number: 4757202
    Abstract: This invention provides a direct reading solid-state dosimeter which will measure neutron and gamma radiation. A dual metal-oxide-semiconductor field-effect transistor (MOSFET) is used as a gamma sensor and a forward biased PIN diode as a neutron sensor. A liquid crystal display is provided for displaying the gamma and neutron radiation dosage.
    Type: Grant
    Filed: July 10, 1986
    Date of Patent: July 12, 1988
    Assignee: Canadian Patents & Development Limited
    Inventor: Philip C. East
  • Patent number: 4699751
    Abstract: A dosimeter which incorporates new methods for determining neutron dose. Less than one millirad of dose due to neutrons of all energies down to approximately 10.sup.3 eV can be measured, and the response can be adjusted by design of the dosimeter. The dosimeter utilizes the sputtering of material from a target due to the action of the neutrons and measuring of the amount of sputtered material to determine the dose. The sputtered material may be, for example, a noble gas or an inert solid. Various radiator materials can be included to interact with the neutrons so that the resulting charged particles control the sputtering process and hereby increase the sensitivity of the dosimeter. The target material can be, for example, noble-gas-impregnated polycrystalline or amorphous metals. The sputtered material is analyzed using resonance ionization spectroscopy, sputter-initiated resonance ionization spectroscopy or other methods to determine its quantity and hence the neutron dose.
    Type: Grant
    Filed: October 24, 1983
    Date of Patent: October 13, 1987
    Assignee: Atom Sciences, Inc.
    Inventors: G. Samuel Hurst, Harold W. Schmitt, Norbert Thonnard, Tom J. Whitaker
  • Patent number: 4667107
    Abstract: The invention comprises a neutron detector (50) of very high temporal resolution that is particularly well suited for measuring the fusion reaction neutrons produced by laser-driven inertial confinement fusion targets. The detector comprises a biased two-conductor traveling-wave transmission line (54, 56, 58, 68) having a uranium cathode (60) and a phosphor anode (62) as respective parts of the two conductors. A charge line and Auston switch assembly (70, 72, 74) launch an electric field pulse along the transmission line. Neutrons striking the uranium cathode at a location where the field pulse is passing, are enabled to strike the phosphor anode and produce light that is recorded on photographic film (64). The transmission line may be variously configured to achieve specific experimental goals.
    Type: Grant
    Filed: June 19, 1985
    Date of Patent: May 19, 1987
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Ching L. Wang
  • Patent number: 4646068
    Abstract: A layer of hydrogenous material, such as ice which may accumulate on an outer airplane surface, is monitored according to neutron moderation by the layer.A source of fast neutrons and a detector of slow neutrons are mounted on one side of a mounting plate which may be the skin of an airplane. As a layer of ice or other hydrogenous material accumulates on the outer surface of the mounting plate, some of the fast neutrons collide with hydrogen nuclei therein to lose energy and be scattered into the slow neutron detector where each detected slow neutron generates an electrical pulse. The electrical pulses are transformed into a signal which corresponds to the amount of hydrogenous material per unit area.
    Type: Grant
    Filed: August 3, 1984
    Date of Patent: February 24, 1987
    Inventor: Stephen F. Skala
  • Patent number: 4642466
    Abstract: An amplifier-discriminator is tailored to output a very short pulse upon an above-threshold input from a detector which may be a .sup.3 He detector. The short pulse output is stretched and energizes a light emitting diode (LED) to provide a visual output of operation and pulse detection. The short pulse is further fed to a digital section for processing and possible ORing with other like generated pulses. Finally, the output (or ORed output ) is fed to a derandomizing buffer which converts the rapidly and randomly occurring pulses into synchronized and periodically spaced-apart pulses for the accurate counting thereof. Provision is also made for the internal and external disabling of each individual channel of amplifier-discriminators in an ORed plurality of same.
    Type: Grant
    Filed: March 5, 1985
    Date of Patent: February 10, 1987
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: James E. Swansen
  • Patent number: 4634568
    Abstract: Disclosed is a neutron detector, provided with a sealed chamber having two spaced apart electrodes, hermetically sealed in the chamber with a seal which is located in an environment of at least two decades less neutron flux than that experienced by the detector. An ionizable gas is placed within the space between the electrodes, and pressurized to a pressure above one atmosphere. A layer of a mixture of an active material and a breeding material are positioned within the chamber, the active material and breeding material being respectively U-235 and U-234, which layer has a thickness of at least 0.2 milligrams per square centimeter.
    Type: Grant
    Filed: October 19, 1983
    Date of Patent: January 6, 1987
    Assignee: General Electric Company
    Inventors: Lealon C. Wimpee, John P. Sturtz, John P. Neissel
  • Patent number: 4617167
    Abstract: A detector apparatus for differentiating between gamma and neutron radiation is provided. The detector includes a pair of differentially shielded Geiger-Mueller tubes. The first tube is wrapped in silver foil and the second tube is wrapped in lead foil. Both the silver and lead foils allow the passage of gamma rays at a constant rate in a gamma ray only field. When neutrons are present, however, the silver activates and emits beta radiation that is also detected by the silver wrapped Geiger-Mueller tube while the radiation detected by the lead wrapped Geiger-Mueller tube remains constant. The amount of radiation impinging on the separate Geiger-Mueller tubes is then correlated in order to distinguish between the neutron and gamma radiations.
    Type: Grant
    Filed: March 6, 1984
    Date of Patent: October 14, 1986
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Lyle W. Kruse, Richard P. McKnight
  • Patent number: 4581813
    Abstract: A method for fabricating a thermocouple unit for service in and about nuclear reactors and other radioactive environments. The method provides a thermocouple encapsulated within a sphere of fissile material.
    Type: Grant
    Filed: October 17, 1984
    Date of Patent: April 15, 1986
    Assignee: General Electric Company
    Inventor: James H. Terhune