EP1493045A2 - Procede et dispositif d'analyse chimique non destructive rapide d'objets de mesure - Google Patents

Procede et dispositif d'analyse chimique non destructive rapide d'objets de mesure

Info

Publication number
EP1493045A2
EP1493045A2 EP03729816A EP03729816A EP1493045A2 EP 1493045 A2 EP1493045 A2 EP 1493045A2 EP 03729816 A EP03729816 A EP 03729816A EP 03729816 A EP03729816 A EP 03729816A EP 1493045 A2 EP1493045 A2 EP 1493045A2
Authority
EP
European Patent Office
Prior art keywords
photon
measurement object
photon energy
energy spectrum
characteristic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP03729816A
Other languages
German (de)
English (en)
Inventor
Stefan RÖTTGER
Uwe Keyser
Annette RÖTTGER
Andreas Zimbal
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bundesrepublik Deutschland
Original Assignee
Bundesrepublik Deutschland
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bundesrepublik Deutschland filed Critical Bundesrepublik Deutschland
Publication of EP1493045A2 publication Critical patent/EP1493045A2/fr
Withdrawn legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K5/00—Irradiation devices
    • G21K5/02—Irradiation devices having no beam-forming means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/02—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material
    • G01N23/025—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material using neutrons
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/22—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material
    • G01N23/221—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material by activation analysis
    • G01N23/222—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material by activation analysis using neutron activation analysis [NAA]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/10—Nuclear fusion reactors

Definitions

  • the invention relates to a method for the non-destructive chemical analysis of measurement objects by irradiating the measurement object with neutrons generated by target-free fusion of concentrically accelerated deuterium ions and measuring the amount of gamma photon radiation emitted promptly during the irradiation from the number of gamma photon quanta and the like respective photon energy for recording a photon energy spectrum.
  • the invention further relates to a device for the non-destructive chemical analysis of measurement objects with a neutron source for briefly irradiating the measurement object with neutrons generated by target-free fusion of concentrically accelerated deuterium ions and with at least one photon detector aimed at the measurement object for measuring the immediately after irradiation of the Measurement object promptly emitted the amount of gamma photon radiation from the number of gamma photon quanta and the respective photon energy.
  • WO 01 / 07888A2 and US Pat. No. 5,539,788 disclose the neutron activation analysis as a nuclear physical analysis method, with a small part due to the irradiation of stable nuclides with neutrons artificial radioactive nuclides are generated. During the subsequent beta decay of the generated nuclides, electrons are emitted and the gamma spectrum of the neutron-activated material to be analyzed is measured. Element concentrations can be determined very precisely from the gamma spectrum.
  • the neutron activation analysis disadvantageously requires a high required neutron density in or on a reactor core and, in connection with this, a strong activation of the measurement object.
  • stable elements with the exception of the last stable isotope and if the half-life is sufficiently long cannot be detected, since these are converted into another isotope or element after activation of a neutron.
  • Tsahi Gozani Novel applications of fast neutron interrogation methods in: Nuclear Instruments & Methods in Physics Research A 353 (1994) 635 to 640 describes a method for ⁇ -spectral analysis of luggage with a neutron activation analysis using 14 MeV neutrons.
  • spectra are examined that are based on the nuclear reactions with the formation of new radionuclides or isomers due to neutron activation.
  • a photon energy spectrum (n, ⁇ spectrum) is measured from the number of photon quanta per photon energy and the molar mass of the silicon sphere is determined from the emitted photon radiation energy.
  • n, ⁇ spectrum is measured from the number of photon quanta per photon energy and the molar mass of the silicon sphere is determined from the emitted photon radiation energy.
  • Destructive analysis methods are conventionally used for the chemical analysis of measurement objects to determine the elements and / or isotopes. When measuring, therefore, only samples can be examined for the presence of individual elements or isotopes in a relatively complex manner.
  • the object of the invention was therefore to create an improved method for the non-destructive chemical analysis of measurement objects, with which all elements and / or isotopes present in a measurement object can be determined very easily and quickly.
  • Quantities of photon radiation of the entire photon energy spectrum at least up to the range of 12 MeV and
  • Determining the elements and / or isotopes of the measurement object by assigning the characteristic photon energies distributed over the entire photon energy spectrum to corresponding elements and / or isotopes that are clearly stored in each case to form a photon energy.
  • the method has the advantage that all isotopes occurring in nature can be detected.
  • the measurement object only has to be irradiated without the need for prior sample preparation.
  • the sample geometry and the physical state of the measurement object are also arbitrary.
  • the photon energy spectrum corresponds to a recorded light frequency spectrum.
  • a quantitative determination of the chemical composition of the measurement object can preferably be carried out by measuring the complete measurable range of the gamma-photon energy spectrum and determining the proportions of the specific elements and / or isotopes by relating the amount of gamma-photon radiation per element and / or isotope to the total for all characteristic gamma-photon radiation amount determined.
  • the number of photon quanta of the individual characteristic photon energies, which protrude as pulse peaks from the curve of the recorded photon energy spectrum, are thus standardized, and the percentage distribution of the elements or isotopes determined over the entire mass of the measurement object can be calculated in a simple manner.
  • the amounts of photon radiation are preferably determined, for example, using known methods for processing measurement curves by determining the areas of the characteristic pulse curves of the photon energy spectrum at the regions of the characteristic photon energies. The pulse peaks projecting beyond the base curve of the photon energy spectrum are thus recognized and the areas under these pulse peaks are calculated.
  • a base photon energy spectrum of the measurement space is preferably recorded without the measurement object, and a photon energy spectrum used for evaluation is calculated from the difference between the photon energy spectrum recorded for analysis and the base photon energy spectrum. It is particularly advantageous to irradiate sections of the measurement object from several directions and to evaluate the multiple measurement results for a location-dependent analysis of the measurement object. In this way, the measurement object is scanned comparable to a tomography device and provides a three-dimensional spatial resolution of the isotope or element concentration.
  • the measuring objects Due to the short irradiation times and the low required energy of the thermal neutrons of E ⁇ 25 meV, the measuring objects are not adversely affected, so that the method can also be used for examining living objects, for example.
  • the object is further achieved by the generic device in that the neutron source is a neutron generator arranged next to the measurement object.
  • An evaluation computing unit is coupled to the at least one photon detector, which unit is used to determine characteristic photon energies from the gamma-photon radiation amounts of the photon energy spectrum going beyond a basic photon radiation and to determine the elements and / or isotopes of the measurement object by assigning the characteristic photon energies to the corresponding photon energy stored elements and / or isotopes is formed.
  • the at least one photon detector is shielded with means for absorbing neutrons. In this way, the scattering influence of photons that are not emitted by the measurement object can be reduced and the photon detector can be aligned as precisely as possible with the measurement object.
  • a focusing element is preferably provided between the neutron generator and the measurement object, which is designed for thermal adaptation of the neutrons.
  • the neutron velocity is adapted, for example, to the Brownian movement of the air, so that thermal neutrons are almost exclusively present in the neutron beam.
  • the focusing element can be designed, for example, as a neutron-absorbing plate with a passage bore.
  • a suitable material for the shielding of the neutron detector and the focusing element are all materials with a high neutron entrance cross section.
  • FIG. 1 shows a basic block diagram of the method according to the invention for non-destructive chemical analysis
  • Fig. 2 is a schematic representation of the immersion of a neutron in an atomic nucleus and the emission of gamma-photon energy
  • Fig. 4 - a block diagram of a device according to the invention for non-destructive chemical analysis.
  • FIG. 1 shows a schematic block diagram of the method according to the invention for the non-destructive chemical analysis of measurement objects 1.
  • the measurement object 1 is briefly or continuously irradiated with neutrons n, which are arranged in the vicinity of the measurement object 1, and which each immerse into the atomic nuclei.
  • neutrons n which are arranged in the vicinity of the measurement object 1, and which each immerse into the atomic nuclei.
  • gamma-photon energy E ⁇ is emitted.
  • a part of the emitted gamma photon quanta is measured with a gamma photon detector 3 and sent to an evaluation computing unit 5 via measuring electronics 4 known per se.
  • a photon energy spectrum 6 is first recorded there in the step of data acquisition D by plotting the number N of photon quanta over the respective photon energy E ⁇ .
  • characteristic photon energies E ⁇ are determined as the amount of gamma-photon radiation in the photon energy spectrum 6 going beyond a basic photon radiation, by detecting the pulse peaks, for example, by means of known signal curve evaluation methods.
  • the elements and / or isotopes present in the measurement object 1 are then determined from the characteristic photon energies E ⁇ by assignment to the corresponding known elements and / or isotopes that are clearly stored in each case to a photon energy.
  • the areas below the characteristic pulse curves of the photon energy spectrum are determined at the regions of the characteristic photon energies E ⁇ .
  • the proportions of the elements in the total mass of the measurement object 1 can then be determined very precisely, since the recorded photon energy spectrum 6 takes into account all known elements and / or isotopes.
  • a complete chemical analysis of the measurement object 1 can thus be carried out with a single measurement, without the measurement object 1 having to be prepared or an examination being necessary for the presence of individual elements or isotopes.
  • FIG. 2 shows the basic physical principle on which the method is based in a schematic representation.
  • the prompt process shown lasts at most 10 "17 seconds from the immersion of the neutron in the atomic nucleus.
  • FIG. 3 shows an exemplary gamma photon energy spectrum recorded with the method with characteristic pulse curves at characteristic photon energies of 380.99 keV, 393.65 keV, 41 1, 80 keV, 418.59 keV, 440.08 keV and 444, 15 keV detect.
  • the number of photons N is determined from the areas below these characteristic pulse curves.
  • FIG. 4 shows a block diagram of a device according to the invention for non-destructive chemical analysis of a measurement object 1.
  • the neutron beam n is directed to the measurement object 1.
  • a neutron moderator 7 for adapting the neutron speed to generate thermal neutrons n, which are adapted to the Brownian movement of the air
  • a focusing means 8 for focusing the neutron beam n:
  • Adjacent to the measurement object 1 is a gamma photon detector 3, which is aligned with the measurement object 1 and is designed to record a photon energy spectrum. With the aid of a multi-channel measurement, the number of photon quanta as a function of the respective photon energy E ⁇ or the light frequency v of the photons is measured and fed to an evaluation computing unit 5.
  • the at least one photon detector 3 is laterally provided with a shield 9 in order to reduce the effects of interference radiation.
  • Suitable materials for the neutron moderator 7, the focusing means 8 and the shielding 9 are all materials with a small atomic number and a small cross-section, for example polyethylene, which is mixed with a catalyst.
  • the focusing means 7 is designed, for example, as a plate with a hole.
  • the evaluation computing unit 5 is designed, for example, in terms of program technology to determine the characteristic photon energies E ⁇ from the photon radiation quantities of the photon energy spectrum that go beyond a basic photon radiation by means of signal analysis.
  • the evaluation computing unit 5 accesses a stored table 10 in which the characteristic photon energies E ⁇ of all known isotopes and thus also of the elements are stored.
  • By correlating the determined Characteristic photon energies E ⁇ with the photon energies E ⁇ for the isotopes stored in Table 10 can now be clearly concluded from the photon energy spectrum on the chemical composition of the measurement object 1.
  • the proportion of the individual isotopes in the total mass under consideration can also be determined with high precision.
  • the measurement object 1 is scanned with the aid of a three-dimensional measurement, so that a location analysis can be carried out similarly to a tomography method.
  • the invention can preferably be used wherever a qualitative and / or quantitative isotope or element detection of samples of any physical state and any geometry is concerned. This is particularly the case for the prospection of raw materials, material analysis, quality control and quality assurance, in the investigative and forensic area (preservation of evidence, evidence of evidence), the detection of weapons and explosives at airports, as well as pure substance analysis in the chemical industry.

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  • Physics & Mathematics (AREA)
  • General Health & Medical Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Engineering & Computer Science (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)

Abstract

L'invention concerne un procédé d'analyse chimique non destructive d'objets de mesure (1) par irradiation de l'objet de mesure (1) avec des neutrons et mesure de la quantité de rayonnement de photons gamma émis directement après irradiation de l'objet de mesure (1), à partir du nombre de quanta de photons gamma et de l'énergie de photons correspondante (E<), de manière à enregistrer un spectre d'énergie de photons (6). Ledit procédé consiste à déterminer des énergies de photons caractéristiques (E?) à partir des quantités de rayonnement de photons gamma du spectre d'énergie de photons (6) dépassant un rayonnement de photons de base, et à déterminer les éléments et/ou isotopes de l'objet de mesure (1) par affectation des énergies de photons caractéristiques (E?) à des éléments et/ou isotopes correspondants enregistrés de façon univoque à une énergie de photons (E?).
EP03729816A 2002-04-05 2003-04-02 Procede et dispositif d'analyse chimique non destructive rapide d'objets de mesure Withdrawn EP1493045A2 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10215070A DE10215070A1 (de) 2002-04-05 2002-04-05 Verfahren und Einrichtung zur prompten zerstörungsfreien chemischen Analyse von Messobjekten
DE10215070 2002-04-05
PCT/DE2003/001084 WO2003085418A2 (fr) 2002-04-05 2003-04-02 Procede et dispositif d'analyse chimique non destructive rapide d'objets de mesure

Publications (1)

Publication Number Publication Date
EP1493045A2 true EP1493045A2 (fr) 2005-01-05

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP03729816A Withdrawn EP1493045A2 (fr) 2002-04-05 2003-04-02 Procede et dispositif d'analyse chimique non destructive rapide d'objets de mesure

Country Status (5)

Country Link
US (1) US20050195932A1 (fr)
EP (1) EP1493045A2 (fr)
AU (1) AU2003240384A1 (fr)
DE (1) DE10215070A1 (fr)
WO (1) WO2003085418A2 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006033662A1 (de) 2006-07-20 2008-01-24 Forschungszentrum Dresden - Rossendorf E.V. Verfahren zum Bestimmen einer Materialzusammensetzung einer Materialprobe
DE102006033661A1 (de) * 2006-07-20 2008-01-24 Forschungszentrum Dresden - Rossendorf E.V. Detektoranordnung zur winkelauflösenden Detektion von Strahlung und Verfahren zum Betrieb desselben
RU2751586C2 (ru) * 2017-05-31 2021-07-15 Аахен Институт Фор Ньюклеар Трейнинг Гмбх Способ и устройство для многоэлементного анализа на основании нейтронной активации, а также применение
ES2831850T3 (es) * 2017-05-31 2021-06-09 Aachen Inst For Nuclear Training Gmbh Procedimiento y dispositivo para el análisis multielemento basado en la activación de neutrones y uso

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US4397810A (en) * 1979-03-16 1983-08-09 Energy Profiles, Inc. Compressed beam directed particle nuclear energy generator
FR2652651B1 (fr) * 1989-10-03 1991-12-13 Commissariat Energie Atomique Systeme de detection de substances et en particulier d'explosifs, par irradiation neutronique de ceux-ci.
US5539788A (en) * 1992-10-08 1996-07-23 Westinghouse Electric Corporation Prompt gamma neutron activation analysis system
US5383538A (en) * 1993-10-04 1995-01-24 Eaton Corporation Brake squeal spring clip dampener
IL129609A0 (en) * 1996-11-01 2000-02-29 Miley George H Spherical inertial electrostatic confinement device as a tunable x-ray source
US5982838A (en) * 1997-03-26 1999-11-09 Western Kentucky University Method and portable apparatus for the detection of substances by use of neutron irradiation
DE19745669B4 (de) * 1997-10-17 2004-03-04 Bruker Daltonik Gmbh Analysensystem zur zerstörungsfreien Identifikation des Inhalts von Objekten, insbesondere von Sprengstoff und chemischen Kampfstoffen
EE200000528A (et) * 1997-11-12 2002-02-15 The Board Of Trustees Of The University Of Illinois Seade ja meetod suurte ioonvoolude impulsside genereerimiseks inertsiaal-elektrostaatilise vangistusega seadmes
AU6607200A (en) * 1999-07-23 2001-02-13 Westinghouse Electric Company Llc Pulsed gamma neutron activation analysis (pgnaa) method and apparatus for nondestructive assay of containerized contaminants

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Title
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Also Published As

Publication number Publication date
DE10215070A1 (de) 2003-10-30
US20050195932A1 (en) 2005-09-08
AU2003240384A8 (en) 2003-10-20
WO2003085418A2 (fr) 2003-10-16
AU2003240384A1 (en) 2003-10-20
WO2003085418A3 (fr) 2003-12-18

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