CN113050148A - Method for measuring abundance of uranium-235 - Google Patents
Method for measuring abundance of uranium-235 Download PDFInfo
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- CN113050148A CN113050148A CN202110276873.5A CN202110276873A CN113050148A CN 113050148 A CN113050148 A CN 113050148A CN 202110276873 A CN202110276873 A CN 202110276873A CN 113050148 A CN113050148 A CN 113050148A
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- characteristic peak
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/167—Measuring radioactive content of objects, e.g. contamination
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/20—Measuring radiation intensity with scintillation detectors
- G01T1/202—Measuring radiation intensity with scintillation detectors the detector being a crystal
Abstract
The embodiment of the application provides a method for measuring abundance of uranium-235, which comprises the following steps: and obtaining the target characteristic peak intensity radiated by the sample to be detected, and obtaining the abundance of uranium-235 in the sample to be detected according to the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity radiated by the sample to be detected. The abundance of the uranium-235 in the sample to be detected can be obtained by obtaining the intensity of the target characteristic peak radiated by the sample to be detected and combining the corresponding relation between the abundance of the uranium-235 and the intensity of the target characteristic peak. The intensity of the target characteristic peak is the intensity of the gamma ray characteristic peak radiated by uranium-235, and the acquisition of the intensity of the gamma ray characteristic peak does not need to destroy a sample to be measured, so that the acquisition process of the intensity of the target characteristic peak radiated by the sample to be measured does not need to destroy the sample to be measured, and the nondestructive measurement of the sample to be measured can be realized.
Description
Technical Field
The application relates to the technical field of nondestructive analysis of nuclear materials, in particular to a method for measuring abundance of uranium-235.
Background
The abundance of uranium-235 is also called uranium-235 enrichment degree, and the enrichment degree of uranium-235 is the proportion of the content of uranium-235 in a sample to be detected. The enrichment of uranium-235 can generally be expressed by the mass percentage of uranium-235 in the sample to be tested. There is no non-destructive measurement method for uranium-235 abundance in the prior art.
Disclosure of Invention
In view of the above, the embodiments of the present application are intended to provide a method for measuring the abundance of uranium-235, so as to achieve non-destructive measurement of the abundance of uranium-235.
In order to achieve the above object, an aspect of the embodiments of the present application provides a method for measuring abundance of uranium-235, including the following steps:
acquiring the intensity of a target characteristic peak radiated by a sample to be detected, wherein the intensity of the target characteristic peak is the intensity of a gamma ray characteristic peak radiated by uranium-235;
and obtaining the abundance of the uranium-235 in the sample to be detected according to the corresponding relation between the abundance of the uranium-235 and the intensity of the target characteristic peak radiated by the sample to be detected.
In an embodiment, before obtaining the abundance of uranium-235 in the sample to be measured according to the correspondence between the abundance of uranium-235 and the target characteristic peak intensity radiated by the sample to be measured, the measurement method further includes:
establishing a mathematical model of the abundance of uranium-235 according to the target characteristic peak intensity;
acquiring target characteristic peak intensity radiated by each standard sample in a plurality of standard samples, wherein the abundance of uranium-235 of each standard sample and the radiated target characteristic peak intensity form a data point;
and fitting the data points according to the mathematical model, wherein the fitting result of the data points is an expression of uranium-235 abundance, and the corresponding relation between the uranium-235 abundance and the target characteristic peak intensity is the expression of the uranium-235 abundance.
In one embodiment, the corresponding relationship between the abundance of uranium-235 and the target characteristic peak intensity is a linear relationship, and the mathematical model is as follows:
y＝a*x+b
wherein:
y is the abundance of uranium-235;
x is the target characteristic peak intensity;
a. and b are all coefficients.
In one embodiment, the target characteristic peak intensity radiated by each of the standard samples is obtained by a measurement system, and the thickness of each of the standard samples is greater than a first preset thickness along the axial direction of a collimator of the measurement system, where the first preset thickness is: the energy is 7 times of the mean free path of the gamma ray of the target characteristic peak in the standard sample.
In one embodiment, the target characteristic peak intensity radiated by the standard sample and the target characteristic peak intensity radiated by the sample to be measured are both obtained by a measuring system in a preset state, and in the preset state, the address of the measuring system corresponds to preset energy; the measurement method further comprises: and carrying out energy calibration on the measuring system so as to enable the measuring system to be in a preset state.
In one embodiment, a first preset distance is formed between the collimator of the measurement system and the standard sample, a second preset distance is formed between the collimator of the measurement system and the sample to be measured, and the first preset distance is equal to the second preset distance.
In one embodiment, the corresponding relationship between the abundance of uranium-235 and the target characteristic peak intensity is:
y＝0.0038x+0.0504
wherein:
y is the abundance of uranium-235;
and x is the target characteristic peak intensity.
In one embodiment, the target characteristic peak is 185.7 keV.
In one embodiment, the intensity of the target characteristic peak radiated by the sample to be measured is obtained by a measurement system, and along the axis direction of a collimator of the measurement system, the thickness of the sample to be measured is greater than a second preset thickness, where the second preset thickness is: the energy of the gamma ray is 7 times of the mean free path of the gamma ray of the target characteristic peak in the sample to be detected.
A second aspect of the embodiments of the present application provides a measurement system, where the measurement system is configured to implement any one of the measurement methods described above, and the measurement system includes:
a detector having a kalicetone-type scintillation crystal CLLB or a detector having a kalicetone-type scintillation crystal CLYC; and
and the collimator is positioned at the measuring receiving end of the detector.
According to the measuring method, the target characteristic peak intensity radiated by the sample to be measured is obtained, and the corresponding relation between the abundance of the uranium-235 and the target characteristic peak intensity is combined, so that the abundance of the uranium-235 in the sample to be measured can be obtained. The intensity of the target characteristic peak is the intensity of the gamma ray characteristic peak radiated by uranium-235, and the acquisition of the intensity of the gamma ray characteristic peak does not need to destroy a sample to be measured, so that the acquisition process of the intensity of the target characteristic peak radiated by the sample to be measured does not need to destroy the sample to be measured, and the nondestructive measurement of the sample to be measured can be realized.
Drawings
FIG. 1 is a flow chart of a measurement method according to an embodiment of the present application;
FIG. 2 is a uranium-235 abundance curve fitted to a plurality of data points in an embodiment of the present application, the uranium-235 abundance curve corresponding to a uranium-235 expression;
fig. 3 is a measurement system according to an embodiment of the present application.
Description of reference numerals: a detector 1; a collimator 2; sample 3; a viewable volume 31.
Detailed Description
It should be noted that, in the present application, technical features in examples and embodiments may be combined with each other without conflict, and the detailed description in the specific embodiment should be understood as an explanation of the gist of the present application and should not be construed as an improper limitation to the present application.
The research finds that a certain corresponding relation exists between the abundance of the uranium-235 and the target characteristic peak intensity. By utilizing the corresponding relation between the abundance of the uranium-235 and the target characteristic peak intensity, the corresponding abundance of the uranium-235 can be obtained as long as the target characteristic intensity radiated by the sample to be detected can be obtained.
In view of this, an embodiment of the present application provides a method for measuring abundance of uranium-235, please refer to fig. 1, where the method includes the following steps:
acquiring the intensity of a target characteristic peak radiated by a sample to be detected, wherein the intensity of the target characteristic peak is the intensity of a gamma ray characteristic peak radiated by uranium-235;
and obtaining the abundance of the uranium-235 in the sample to be detected according to the corresponding relation between the abundance of the uranium-235 and the intensity of the target characteristic peak radiated by the sample to be detected.
Therefore, the abundance of the uranium-235 in the sample to be detected can be obtained by acquiring the intensity of the target characteristic peak radiated by the sample to be detected and combining the corresponding relation between the abundance of the uranium-235 and the intensity of the target characteristic peak. The intensity of the target characteristic peak is the intensity of the gamma ray characteristic peak radiated by uranium-235, and the acquisition of the intensity of the gamma ray characteristic peak does not need to destroy a sample to be measured, so that the acquisition process of the intensity of the target characteristic peak radiated by the sample to be measured does not need to destroy the sample to be measured, and the nondestructive measurement of the sample to be measured can be realized.
It should be noted that the intensity of the gamma ray characteristic peak is usually expressed by a count rate.
In one embodiment, the target characteristic peak is 185.7 keV.
It is understood that the intensity of the characteristic gamma ray peak can be obtained by a gamma ray energy spectrum. In one embodiment, obtaining the target characteristic peak intensity radiated by the sample to be detected includes:
acquiring a first gamma ray energy spectrum radiated by a sample to be detected;
and obtaining the target characteristic peak intensity radiated by the sample to be detected according to the first gamma ray energy spectrum.
It should be explained that, the gamma ray energy spectrum takes the energy of the gamma ray as the horizontal axis and the intensity corresponding to the energy of the gamma ray as the vertical axis, and the characteristic peak of the gamma ray can be understood as an energy value on the horizontal axis of the gamma ray energy spectrum. The ordinate corresponding to the gamma ray characteristic peak is the intensity of the gamma ray characteristic peak. The target characteristic peak and the corresponding target characteristic peak intensity can be definitely identified through the first gamma ray energy spectrum of the sample to be detected.
In one embodiment, the first gamma-ray energy spectrum is acquired by a measurement system. Therefore, the target characteristic peak intensity can be obtained according to the first gamma ray energy spectrum, so that the target characteristic peak intensity can be obtained through the measuring system, and the target characteristic peak intensity radiated by the sample to be measured can be conveniently obtained through the measuring system.
In one embodiment, the target characteristic peak intensity may be obtained by a measurement system in a preset state, where a track address of the measurement system corresponds to a preset energy.
It can be understood that when the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity is known, the abundance of uranium-235 can be directly calculated according to the target characteristic peak intensity. In one embodiment, referring to fig. 2, the corresponding relationship between the abundance of uranium-235 and the target characteristic peak intensity is:
y＝0.0038x+0.0504 (1)
in formula (1):
y is the abundance of uranium-235;
and x is the target characteristic peak intensity.
Thus, the uranium-235 abundance in the sample to be detected can be obtained by substituting the obtained target characteristic peak intensity radiated by the sample to be detected into the formula (1).
It can be understood that, as shown in formula (1), the abundance of uranium-235 is proportional to the target characteristic peak intensity.
It will be appreciated that the correspondence between uranium-235 abundance and target characteristic peak intensity may not be fully defined. In an embodiment, referring to fig. 1, before obtaining the abundance of uranium-235 in the sample to be measured according to the correspondence between the abundance of uranium-235 and the target characteristic peak intensity radiated by the sample to be measured, the measuring method further includes:
establishing a mathematical model of the abundance of uranium-235 according to the target characteristic peak intensity;
acquiring target characteristic peak intensity radiated by each standard sample in a plurality of standard samples, wherein the abundance of uranium-235 of each standard sample and the radiated target characteristic peak intensity form a data point;
and fitting the data points according to the mathematical model, wherein the fitting result of the data points is an expression of uranium-235 abundance, and the corresponding relation between the uranium-235 abundance and the target characteristic peak intensity is the expression of the uranium-235 abundance.
Thus, the target characteristic peak intensity radiated by each standard sample is obtained, because the abundance of the uranium-235 of each standard sample is known, the abundance of the uranium-235 of each standard sample and the radiated target characteristic peak intensity form one data point, a plurality of data points can be obtained by a plurality of standard samples, fitting the scatter data according to a mathematical model can obtain an expression of the abundance of uranium-235, and the expression of the abundance of uranium-235 is used as the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity, because the data model is established according to the intensity of the target characteristic peak, the obtained expression of the abundance of the uranium-235 is associated with the intensity of the target characteristic peak, as long as the intensity of the target characteristic peak radiated by the sample to be detected is obtained, and substituting the uranium abundance into an expression of the uranium-235 abundance to obtain the uranium-235 abundance in the corresponding sample to be detected.
It should be explained that the standard sample refers to a sample with known abundance of uranium-235.
In one embodiment, the fitting of the plurality of data points is performed by least squares.
In one embodiment, obtaining the target characteristic peak intensity radiated by each of a plurality of standard samples comprises:
acquiring a second gamma ray energy spectrum radiated by each standard sample;
and obtaining the target characteristic peak intensity radiated by the standard sample according to the second gamma ray energy spectrum.
In one embodiment, the uranium-235 abundance is in a linear relationship with the target characteristic peak intensity, and the mathematical model is as follows:
y＝a*x+b (2)
wherein:
y is the abundance of uranium-235;
x is the target characteristic peak intensity;
a. and b are all coefficients.
Thus, the mathematical model can reflect the corresponding relation between the abundance of the uranium-235 and the target characteristic peak intensity more truly.
It is understood that the coefficient a and the coefficient b may be unknown, and therefore, the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity reflected by the mathematical model is unknown, and the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity is not completely clear. Obtaining a data point corresponding to each standard sample by obtaining the target characteristic peak intensity radiated by each standard sample, obtaining a plurality of data points by a plurality of standard samples, fitting the plurality of standard data points according to a mathematical model to obtain the values of a coefficient a and a coefficient b, thus obtaining an expression of the abundance of uranium-235, and determining the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity.
In one embodiment, referring to fig. 2, the expression of the uranium-235 abundance obtained by final fitting according to the mathematical model of formula (2) is shown as formula (1).
In one embodiment, reference R in FIG. 2 is the goodness of fit, R2The closer to 1, the better the fit.
It can be understood that after the expression of the uranium-235 abundance is obtained through the mathematical model and the standard sample, the obtained target characteristic peak intensity radiated by the sample to be detected is substituted into the expression of the uranium-235 abundance, that is, the uranium-235 abundance of the sample to be detected can be obtained.
It can be understood that the target characteristic peak intensity radiated by the standard sample and the target characteristic peak intensity radiated by the sample to be measured are obtained by the measuring system, and each expression of the abundance of uranium-235 corresponds to the state of the specific measuring system. The state of the measurement system changes and the expression for the abundance of uranium-235 may change accordingly. Illustratively, with reference to equation (2), the corresponding coefficient a and/or coefficient b of the measurement system may be different under different conditions, and thus may correspond to different expressions of uranium-235 abundance.
In one embodiment, the target characteristic peak intensity radiated by the standard sample and the target characteristic peak intensity radiated by the sample to be measured are both obtained by the measuring system in a preset state, and in the preset state, the address of the measuring system corresponds to the preset energy; the measuring method further comprises the following steps: and carrying out energy calibration on the measuring system so as to enable the measuring system to be in a preset state. Therefore, no matter the standard sample is measured or the sample to be measured is measured, the state of the measuring system is in a preset state, the state of the measuring system is the same, the energy corresponding to each channel of the measuring system is determined, the uranium-235 abundance expression obtained by fitting the standard sample is combined with the target characteristic peak intensity radiated by the sample to be measured, and the uranium-235 abundance of the sample to be measured can be accurately obtained.
In one embodiment, referring to fig. 1, energy calibration of the measurement system to keep the measurement system in a preset state includes:
measuring a plurality of standard gamma point sources by using a measuring system, wherein the energy of any two standard gamma point sources is unequal, the preset energy is the energy of the standard gamma point sources, the energy of the standard gamma point source with the minimum energy is first preset energy, the energy of the standard gamma point source with the maximum energy is second preset energy, the first preset energy is smaller than a target characteristic peak, and the second preset energy is larger than the target characteristic peak;
and adjusting the working parameters of the measuring system to make the track address of the measuring system correspond to the energy of the standard gamma point source.
Therefore, the measuring system is used for measuring the standard gamma point source, and the energy scale of the measuring system is realized by adjusting the working parameters of the measuring system, so that the measuring system is in a preset state.
In one embodiment, the operating parameters of the measurement system include an operating voltage of the measurement system, a gain of the measurement system, a measurement time of the measurement system, an energy lower domain of the measurement system, and the like. These operating parameters affect the correspondence of the addresses of the measurement systems to the energies, and adjusting the operating parameters of the measurement systems causes the addresses of the measurement systems to correspond to different energies.
In one embodiment, the operating voltage is the voltage of the detector.
It should be explained that the energy lower range, i.e. the lower energy limit that the measuring system can measure, is set according to the energy of the measured radiation, and the lower energy limit may vary depending on the energy of the measured radiation. The lower energy limit is adjusted to bring the measurement system to a preset state, mainly to reduce interference of the X-rays on the measurement system. The upper energy limit that the measuring system can measure is determined by the energy scale.
In one embodiment, the lower energy limit is 50keV or other energy value.
It should be noted that each track of the measurement system corresponds to an energy value, and the process of performing energy calibration on the measurement system is a process of determining the energy corresponding to each track of the measurement system.
It should be noted that the track address of the measurement system is understood to be the address of the energy track of the measurement system.
In one embodiment, the measurement system is energy scaled using a standard gamma point source.
In one embodiment, the standard gamma point source is typically a sample of a single nuclide.
In one embodiment, the standard gamma point source may be241Am、137Cs or60Co。
In one embodiment, multiple standard gamma point sources may be measured simultaneously by the measurement system.
It should be noted that when the sample 3 is sufficiently large, due to the self-absorption effect of the uranium itself, only a portion of the sample 3 irradiated with the target characteristic peak can be detected, and this portion of the sample 3 is referred to as the visible volume 31 of such sample 3 under the corresponding measurement system. The visible volume 31 of sample 3 is related to the collimator 2 of the measurement system, the operating parameters of the measurement system and the mean free path of the gamma rays with energy as the characteristic peak of interest in sample 3, and is not related to the uranium-235 enrichment of sample 3. And the measurement system measures the sample 3 in substantially the same state, for example, in a preset state, for the same measurement system, therefore, the mean free path of the gamma rays with energy of the target characteristic peak in the sample 3 has a large influence on the visible volume 31 of the sample 3.
In one embodiment, referring to fig. 3, the peak intensity of the target feature radiated by each standard sample is obtained by the measurement system, and the thickness of each standard sample along the axial direction of the collimator 2 of the measurement system is greater than or equal to a first preset thickness, where the first preset thickness is: the energy is 7 times of the mean free path of the gamma ray of the target characteristic peak in the standard sample. In this way, the visible volume 31 of the standard sample reaches the limit, and even if the thickness of the standard sample continues to increase, the target characteristic peak intensity radiated by the standard sample acquired by the measurement system does not increase. The interference of the standard sample size on the measurement result can be reduced to a certain extent, the linear relation between the abundance of the uranium-235 and the target characteristic strength is well ensured, and the accuracy of the measurement result of the abundance of the uranium-235 is improved.
In one embodiment, the measurement system further comprises a barrier impermeable to gamma rays.
In one embodiment, when the thickness of the standard sample is smaller than the first predetermined thickness along the axial direction of the collimator 2 of the measurement system, a barrier that is impenetrable to gamma rays may be disposed on a side of the standard sample facing away from the measurement system.
In one embodiment, the barrier may be a lead plate.
In an embodiment, referring to fig. 3, the intensity of the target characteristic peak radiated by the sample to be measured is obtained by the measurement system, the thickness of the sample to be measured is greater than or equal to a second predetermined thickness in the axial direction of the collimator 2 of the measurement system, and the second predetermined thickness is: the energy is 7 times of the mean free path of gamma rays of a target characteristic peak in a sample to be measured. Thus, the visible volume 31 of the sample to be measured reaches the limit, and even if the thickness of the sample to be measured continues to increase, the target characteristic peak intensity radiated by the sample to be measured, which is acquired by the measurement system, does not increase any more. The interference of the size of the sample to be measured on the measurement result can be reduced to a certain extent, the linear relation between the abundance of the uranium-235 and the target characteristic strength is well ensured, and the accuracy of the measurement result of the abundance of the uranium-235 is improved.
In an embodiment, along the axial direction of the collimator 2 of the measurement system, when the thickness of the sample to be measured is smaller than the second predetermined thickness, a blocking member that cannot be penetrated by gamma rays may be disposed on a side of the sample to be measured away from the measurement system.
In one embodiment, the thickness of the standard sample is greater than or equal to a first preset thickness, and the thickness of the sample to be measured is greater than or equal to a second preset thickness along the axial direction of the collimator 2 of the measurement system. Therefore, the influence of the shape of the standard sample and the shape of the sample to be measured on the target characteristic peak intensity obtained by the measuring system is small.
It should be explained that, with reference to fig. 3, the axial direction of the collimator 2 is the direction indicated by the arrow a in fig. 3.
In one embodiment, a first preset distance is formed between the collimator 2 of the measurement system and the standard sample, a second preset distance is formed between the collimator of the measurement system and the sample to be measured, and the first preset distance is equal to the second preset distance. Therefore, the first preset distance and the second preset distance are kept equal, the visual volume of the standard sample is basically equal to that of the sample to be detected, and the coefficient a and the coefficient b are basically unchanged, so that the expression of the uranium-235 abundance fitted by the standard sample can be better suitable for the sample to be detected, and the measured uranium-235 abundance of the sample to be detected is more accurate.
Specifically, referring to fig. 3, when the sample 3 is a standard sample, the distance D shown in fig. 3 is a first predetermined distance. When the sample 3 is a sample to be measured, the distance D shown in fig. 3 is a second preset distance.
In one embodiment, the measurement system is in a preset state, the thickness of the standard sample along the axial direction of the collimator 2 is greater than or equal to a first preset thickness, and the thickness of the sample to be measured along the axial direction of the collimator 2 is greater than or equal to a second preset thickness.
It should be noted that not every measurement of the sample to be tested requires the repeated execution of the steps of fitting the expression of the abundance of uranium-235 from the mathematical model to a plurality of data points. Under the condition that the corresponding relation between the abundance of the uranium-235 and the target characteristic peak intensity is clear, the abundance of the uranium-235 of the sample to be detected can be obtained by obtaining the target characteristic peak intensity of the sample to be detected.
Specifically, for example, it is known that the corresponding relationship between the abundance of uranium-235 and the target characteristic peak intensity is formula (1), and the abundance of uranium-235 in the sample to be measured can be obtained by obtaining the target characteristic peak intensity and substituting formula (1).
When the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity is formula (1), and the state of the corresponding measurement system is known. The measuring system obtains the target characteristic peak intensity of the sample to be measured in a corresponding state and substitutes formula (1), so that more accurate uranium-235 abundance can be obtained.
The embodiment of the application provides a measuring system, and the measuring system is used for realizing the corresponding measuring method. Referring to fig. 3, the measurement system includes a detector 1 and a collimator 2. The detector 1 has a kaliceite type scintillation crystal CLLB, or the detector 1 has a kaliceite type scintillation crystal CLYC. The collimator 2 is located at the measurement receiving end of the detector 1. In such a structure, when the measurement system is used for measuring the sample 3, the gamma ray radiated by the sample 3 enters the detector 1 after being collimated by the collimator 2, and the detector 1 receives the gamma ray radiated by the sample 3 and performs measurement and analysis.
It is to be explained that the chemical formula of the kalziolite type scintillation crystal CLLB is Cs2LiLaBr6: Ce, and the abbreviation of the chemical formula is CLLB. The chemical formula of the kalicerite type scintillation crystal CLYC is Cs2LiYCl6: Ce, and the abbreviation of the chemical formula is CLYC.
In an embodiment, the collimator 2 is located between the detector 1 and the sample 3.
In one embodiment, the measurement system performs measurements on the sample 3.
In one embodiment, sample 3 may be a standard sample.
In one embodiment, the sample 3 may be a sample to be tested.
In one embodiment, the sample 3 may be a standard gamma point source.
In one embodiment, all the standard samples are identical in shape.
In one embodiment, all samples to be tested have the same shape.
In one embodiment, all of the standard gamma point sources are identical in shape.
In one embodiment, all the standard samples, all the samples to be tested, and all the standard gamma point sources have the same shape.
The various embodiments/implementations provided herein may be combined with each other without contradiction.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. A method for measuring the abundance of uranium-235 is characterized by comprising the following steps:
acquiring the intensity of a target characteristic peak radiated by a sample to be detected, wherein the intensity of the target characteristic peak is the intensity of a gamma ray characteristic peak radiated by uranium-235;
and obtaining the abundance of the uranium-235 in the sample to be detected according to the corresponding relation between the abundance of the uranium-235 and the intensity of the target characteristic peak radiated by the sample to be detected.
2. The method according to claim 1, wherein before obtaining the abundance of uranium-235 in the sample to be measured according to the correspondence between the abundance of uranium-235 and the target characteristic peak intensity radiated by the sample to be measured, the method further comprises:
establishing a mathematical model of the abundance of uranium-235 according to the target characteristic peak intensity;
acquiring target characteristic peak intensity radiated by each standard sample in a plurality of standard samples, wherein the abundance of uranium-235 of each standard sample and the radiated target characteristic peak intensity form a data point;
and fitting the data points according to the mathematical model, wherein the fitting result of the data points is an expression of uranium-235 abundance, and the corresponding relation between the uranium-235 abundance and the target characteristic peak intensity is the expression of the uranium-235 abundance.
3. The method of measurement according to claim 2, wherein the correspondence between the abundance of uranium-235 and the target characteristic peak intensity is a linear relationship, and the mathematical model is:
y＝a*x+b
wherein:
y is the abundance of uranium-235;
x is the target characteristic peak intensity;
a. and b are all coefficients.
4. The measurement method according to claim 2, wherein the target characteristic peak intensity radiated by each of the standard samples is obtained by a measurement system, and the thickness of each of the standard samples in the axial direction of a collimator of the measurement system is greater than a first preset thickness, and the first preset thickness is: the energy is 7 times of the mean free path of the gamma ray of the target characteristic peak in the standard sample.
5. The measurement method according to claim 2, wherein the target characteristic peak intensity radiated by the standard sample and the target characteristic peak intensity radiated by the sample to be measured are both obtained by a measurement system in a preset state in which a track address of the measurement system corresponds to a preset energy; the measurement method further comprises: and carrying out energy calibration on the measuring system so as to enable the measuring system to be in a preset state.
6. The method according to claim 2, wherein the collimator of the measuring system is spaced apart from the standard sample by a first predetermined distance, and the collimator of the measuring system is spaced apart from the sample to be measured by a second predetermined distance, and the first predetermined distance is equal to the second predetermined distance.
7. The method for measuring the peak abundance according to any one of claims 1 to 6, wherein the corresponding relation between the abundance of uranium-235 and the target characteristic peak intensity is as follows:
y＝0.0038x+0.0504
wherein:
y is the abundance of uranium-235;
and x is the target characteristic peak intensity.
8. The measurement method according to any one of claims 1 to 6, wherein the target characteristic peak is 185.7 keV.
9. The measurement method according to any one of claims 1 to 6, wherein the target characteristic peak intensity radiated by the sample to be measured is obtained by a measurement system, and along the axial direction of a collimator of the measurement system, the thickness of the sample to be measured is greater than a second preset thickness, and the second preset thickness is: the energy of the gamma ray is 7 times of the mean free path of the gamma ray of the target characteristic peak in the sample to be detected.
10. A measuring system for implementing the measuring method according to any one of claims 1 to 9, the measuring system comprising:
a detector having a kalicetone-type scintillation crystal CLLB or a detector having a kalicetone-type scintillation crystal CLYC; and
and the collimator is positioned at the measuring receiving end of the detector.
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| CN117250651A (en) * | 2023-11-07 | 2023-12-19 | 中国科学技术大学 | Planet element detection device based on pixel type tellurium-zinc-cadmium detector |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102175704A (en) * | 2011-02-18 | 2011-09-07 | 中国原子能科学研究院 | Uranium isotope abundance analysis method |
| CN103064101A (en) * | 2013-01-04 | 2013-04-24 | 中国原子能科学研究院 | Gama scanning measuring method through adoption of asymmetrical standard sample calibration |
| CN107656305A (en) * | 2017-08-15 | 2018-02-02 | 中国原子能科学研究院 | A kind of method for determining uranium enrichment |
| CN109100001A (en) * | 2018-08-22 | 2018-12-28 | 中国原子能科学研究院 | A kind of UF6The verification measurement method of uranium quality in big tank |
| CN110261417A (en) * | 2019-07-02 | 2019-09-20 | 中国原子能科学研究院 | A kind of uranium Measuring abundance of U-bar system improving monitoring accuracy |
| CN110308474A (en) * | 2019-07-02 | 2019-10-08 | 中国原子能科学研究院 | A kind of small-sized monitoring device for on-line measurement gas uranium abundance |
-
2021
- 2021-03-15 CN CN202110276873.5A patent/CN113050148A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102175704A (en) * | 2011-02-18 | 2011-09-07 | 中国原子能科学研究院 | Uranium isotope abundance analysis method |
| CN103064101A (en) * | 2013-01-04 | 2013-04-24 | 中国原子能科学研究院 | Gama scanning measuring method through adoption of asymmetrical standard sample calibration |
| CN107656305A (en) * | 2017-08-15 | 2018-02-02 | 中国原子能科学研究院 | A kind of method for determining uranium enrichment |
| CN109100001A (en) * | 2018-08-22 | 2018-12-28 | 中国原子能科学研究院 | A kind of UF6The verification measurement method of uranium quality in big tank |
| CN110261417A (en) * | 2019-07-02 | 2019-09-20 | 中国原子能科学研究院 | A kind of uranium Measuring abundance of U-bar system improving monitoring accuracy |
| CN110308474A (en) * | 2019-07-02 | 2019-10-08 | 中国原子能科学研究院 | A kind of small-sized monitoring device for on-line measurement gas uranium abundance |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117250651A (en) * | 2023-11-07 | 2023-12-19 | 中国科学技术大学 | Planet element detection device based on pixel type tellurium-zinc-cadmium detector |
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