Comprehensive analysis method for PGNAA detection data

Abstract

The invention provides a PGNAA detection data comprehensive analysis method, and relates to the technical field of detection, and the method comprises the following steps: obtaining the first element content, neutron absorption cross section, environment temperature variation and humidity of a detected sample; adjusting a ray self-absorption correction coefficient based on the first element content, adjusting flux distribution based on a neutron absorption cross section, calibrating a peak position based on an environment temperature variation, and correcting a background based on environment humidity. According to the method, through processing according to conditions, when relevant parameters exceed threshold values, modes such as cooperative calculation and simulation are adopted, otherwise, standard values are used, accurate comprehensive analysis of PGNAA detection data is achieved, and the accuracy and adaptability of detection results are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of detection, in particular to a PGNAA detection data comprehensive analysis method. BACKGROUND

[0002] With the increasing requirements of industrial production on material composition detection accuracy and efficiency, PGNAA technology is widely used because it can realize non-destructive detection. However, in actual detection, the element content of the measured sample, neutron absorption characteristics and environmental temperature and humidity change dynamically, and these changes will cause deviations in ray self-absorption, flux distribution, peak position and background, affecting the reliability of the detection results.

[0003] The traditional PGNAA detection data comprehensive analysis method does not process different element contents, neutron absorption cross sections and environmental parameters, and usually uses a unified standard value or a simplified model, which cannot take into account the influence of multi-element synergy, complex flux distribution and environmental dynamic changes, resulting in insufficient absorption correction of high content elements, distortion of low content element signals, and detection accuracy difficult to meet the requirements.

[0004] Therefore, it is necessary to design a PGNAA detection data comprehensive analysis method to solve the problem that the prior art does not process element content, neutron absorption cross section and environmental parameter, resulting in large deviation of detection results, insufficient accuracy, and inability to adapt to complex detection scenarios. SUMMARY

[0005] In view of this, the present application provides a PGNAA detection data comprehensive analysis method, which aims to solve the problem that the prior art does not process element content, neutron absorption cross section and environmental parameter, resulting in large deviation of detection results and insufficient accuracy.

[0006] In one aspect, the present application provides a PGNAA detection data comprehensive analysis method, comprising: S1, obtaining the first element content, neutron absorption cross section and environmental temperature change, and environmental humidity of the measured sample; S2, adjusting the ray self-absorption correction coefficient of the first element based on the first element content; S3, adjusting the flux distribution based on the neutron absorption cross section; S4, calibrating the peak position based on the environmental temperature change; S5, correcting the background based on the environmental humidity.

[0007] Further, when adjusting the ray self-absorption correction coefficient of the first element based on the first element content, comprising: When the first element content is greater than a first element content threshold, the ray self-absorption correction coefficient of the first element is determined by using a multi-element synergy calculation method. When the first element content is less than or equal to the first element content threshold value, then the first element ray self-absorption correction coefficient is equal to the standard first element ray self-absorption correction coefficient.

[0008] Further, when determining the first element ray self-absorption correction coefficient by using the multi-element collaborative calculation method, the method comprises the following steps: extracting an absorption interaction element in the measured sample which has absorption interaction with the first element; obtaining the standard first element ray self-absorption correction coefficient, atomic number, content, and ray energy of the first element, and the standard ray self-absorption correction coefficient, atomic number, content, and ray energy of each absorption interaction element; dividing the product of the standard first element ray self-absorption correction coefficient, atomic number, and content of the first element by the ray energy of the first element to obtain a first correction coefficient; dividing the product of the standard ray self-absorption correction coefficient, atomic number, and content of the absorption interaction element by the ray energy of the absorption interaction element to obtain a second correction coefficient; adding the second correction coefficient of each absorption interaction element to obtain a third correction coefficient; summing the third correction coefficient and the first correction coefficient to obtain the first element ray self-absorption correction coefficient.

[0009] Further, when adjusting the flux distribution based on the neutron absorption cross section, the method comprises the following steps: when the neutron absorption cross section is greater than the neutron absorption cross section threshold value, then the flux distribution is determined by using the Monte Carlo simulation method; when the neutron absorption cross section is less than or equal to the neutron absorption cross section threshold value, then the flux distribution is equal to the standard flux distribution.

[0010] Further, when determining the flux distribution by using the Monte Carlo simulation method, the method comprises the following steps: extracting a neutron interaction element in the measured sample which has interaction with neutrons; obtaining the neutron scattering cross section, neutron absorption cross section, and content of the neutron interaction element; dividing the product of the neutron scattering cross section, neutron absorption cross section, and content of the neutron interaction element by a preset neutron energy constant to obtain a first distribution parameter; adding the first distribution parameter of each neutron interaction element to obtain a second distribution parameter; substituting the second distribution parameter into the Monte Carlo simulation model to obtain the flux distribution.

[0011] Further, when calibrating the peak position based on the environmental temperature change amount, the method comprises the following steps: When the environmental temperature change amount is greater than the temperature change threshold, then the peak position calibration value is determined by using a temperature segmented calibration manner; When the environmental temperature change amount is less than or equal to the temperature change threshold, then the peak position calibration value is equal to a standard peak position calibration value.

[0012] Further, when the peak position calibration value is determined by using the temperature segmented calibration manner, the method comprises: dividing the environmental temperature into a plurality of continuous temperature intervals; determining a temperature interval to which a current environmental temperature belongs; obtaining a peak position temperature coefficient corresponding to the temperature interval and a standard peak position value; multiplying the peak position temperature coefficient, a difference between the current environmental temperature and a standard temperature, and the standard peak position value to obtain the peak position calibration value.

[0013] Further, when the background is corrected based on the environmental humidity, the method comprises: When the environmental humidity is greater than a humidity threshold, then a background correction amount is determined by using a humidity dynamic correction manner; When the environmental humidity is less than or equal to the humidity threshold, then the background correction amount is equal to a standard background correction amount.

[0014] Further, when the background correction amount is determined by using the humidity dynamic correction manner, the method comprises: obtaining an initial humidity and a current humidity of the measured sample; calculating a difference between the current humidity and the initial humidity to obtain a humidity change amount; obtaining a preset humidity correction coefficient and a standard background spectrum; multiplying the humidity change amount, the humidity correction coefficient, and the standard background spectrum to obtain the background correction amount.

[0015] Compared with the prior art, the PGNAA detection data comprehensive analysis method has the beneficial effects that the PGNAA detection data comprehensive analysis method determines a ray self-absorption correction coefficient according to the first element content, adjusts the flux distribution according to the neutron absorption cross section, calibrates the peak position based on the environmental temperature change amount, and corrects the background based on the environmental humidity, realizes the targeted processing of different element contents, neutron absorption characteristics, and environmental parameters, avoids the limitations of unified standard values or simplified models, can comprehensively consider the synergistic effect of multiple elements and the influence of environmental factors, and thus improves the accuracy and adaptability of PGNAA detection data comprehensive analysis, and meets the needs of complex detection scenarios. BRIEF DESCRIPTION OF DRAWINGS

[0016] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a better understanding of the preferred embodiments, and are not intended to constrain the application. Moreover, in the drawings, like reference numerals denote same or similar components. In the drawings: Figure 1 A flow chart of a PGNAA detection data comprehensive analysis method provided by an embodiment of the application. DETAILED DESCRIPTION

[0017] Exemplary embodiments of the present application will be described in detail with reference to the drawings. Although exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the application to those skilled in the art. It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict, if possible. The present application will be described in detail with reference to the drawings and in conjunction with the embodiments.

[0018] Referring to Figure 1 In some embodiments of the present application, a PGNAA detection data comprehensive analysis method includes: S1, obtaining a first element content, a neutron absorption cross section, and an environmental temperature variation and an environmental humidity of a sample to be measured; S2, adjusting a ray self-absorption correction coefficient of the first element based on the first element content; S3, adjusting a flux distribution based on the neutron absorption cross section; S4, calibrating a peak position based on the environmental temperature variation; S5, correcting a background based on the environmental humidity.

[0019] Specifically, the first element refers to an element with a large atomic number (atomic number greater than 20) in the periodic table. The atomic nucleus of such an element has more protons and neutrons, and has a strong ability to absorb gamma rays. In PGNAA detection, the content and distribution of such elements in the sample to be detected will significantly affect the self-absorption effect of gamma rays, and in turn affect the accuracy of the detection data. Common examples include iron (Fe, atomic number 26) and lead (Pb, atomic number 82). The content of each element in the sample to be detected is obtained by the following means: using PGNAA technology, irradiating the sample to be detected with a neutron source to cause the elements in the sample to be activated to produce characteristic gamma rays, and then receiving these characteristic gamma rays by a detector. According to the energy and intensity of the characteristic gamma rays, combined with known element characteristic gamma ray information and related calibration curves, the content of each element is calculated. The neutron absorption cross section is obtained by analyzing the main element composition of the sample to be detected, according to the known neutron absorption cross section data of each element, combined with the content proportion of the element in the sample to be detected, and the neutron absorption cross section of the whole sample to be detected is calculated by weighting. The known neutron absorption cross section data of each element comes from the standard value measured by experiment in the nuclear physics database. The gamma ray self-absorption correction coefficient is a parameter used to correct the absorption effect of the sample to be detected on the rays. Through this coefficient, the deviation of the detection data caused by the absorption of the sample to be detected on the rays can be adjusted, so that the analysis result is more in line with the actual situation.

[0020] It can be understood that by determining the ray self-absorption correction coefficient according to the content of the first element, adjusting the flux distribution according to the neutron absorption cross section, calibrating the peak position according to the change in environmental temperature, and correcting the background based on the environmental humidity, the accuracy and adaptability of the comprehensive analysis of PGNAA detection data are improved by realizing the targeted processing of different element contents, neutron absorption characteristics and environmental parameters, avoiding the limitations of uniform standard values or simplified models, and comprehensively considering the synergistic effect of multiple elements and the influence of environmental factors.

[0021] In some embodiments of the present application, when the content of the first element is adjusted to adjust the ray self-absorption correction coefficient of the first element, it includes: When the content of the first element is greater than the first element content threshold, the ray self-absorption correction coefficient of the first element is determined by using a multi-element synergistic calculation method; When the content of the first element is less than or equal to the first element content threshold, the ray self-absorption correction coefficient of the first element is equal to the standard ray self-absorption correction coefficient of the first element.

[0022] Specifically, the first element content threshold is an element content value determined by a critical value at which the first element has a significant effect on the self-absorption of the rays; and the standard ray self-absorption correction coefficient is a reference coefficient determined in advance for the first element or the absorption interactive element under specific standard conditions (such as standard content, standard environment, etc.) and used to correct the intensity attenuation of the rays in the measured sample due to the self-absorption effect. It is usually obtained by experimental measurement, that is, PGNAA detection is performed on a standard sample with known composition and content, the attenuation law of the rays in the standard sample is analyzed by combining a theoretical calculation model (such as Monte Carlo simulation), and then the coefficient is determined; or it can be obtained by referring to the correction coefficient of the same type of element under standard conditions verified in the relevant standard database or literature.

[0023] It can be understood that different ray self-absorption correction coefficient determination methods are set for the content of the first element, the synergistic calculation is used when the content exceeds the threshold, otherwise the standard value is used, thereby avoiding the limitation of a single processing method and improving the adaptability of the correction coefficient.

[0024] In some embodiments of the present application, when the ray self-absorption correction coefficient of the first element is determined by using the multi-element synergistic calculation method, the method comprises: extracting an absorption interactive element in the measured sample that has an absorption interaction with the first element; obtaining the standard ray self-absorption correction coefficient, atomic number, content, and ray energy of the first element, and the standard ray self-absorption correction coefficient, atomic number, content, and ray energy of each absorption interactive element; dividing the product of the standard ray self-absorption correction coefficient, atomic number, and content of the first element by the ray energy of the first element to obtain a first correction coefficient; dividing the product of the standard ray self-absorption correction coefficient, atomic number, and content of the absorption interactive element by the ray energy of the absorption interactive element to obtain a second correction coefficient; adding the second correction coefficients of each absorption interactive element to obtain a third correction coefficient; summing the third correction coefficient and the first correction coefficient to obtain the ray self-absorption correction coefficient of the first element.

[0025] Specifically, by analyzing the differences in atomic numbers between each element in the sample under test and the first element, the overlap of radiation energy absorption cross sections and the correlation between element contents, elements that have a significant impact on the radiation self-absorption of the first element are screened out as absorption interaction elements that have absorption interaction with the first element; radiation energy refers to the specific energy value of the gamma rays released by the first element and the absorption interaction elements in the sample under test after neutron activation. Different elements will release characteristic gamma rays after activation, and their energy is unique, which can be used to identify the type of element; radiation energy is obtained in the following way: use a standard radiation source with known energy (such as cobalt-60, cesium-137, etc.) to calibrate the detector energy, establish a correspondence between the detector output signal and the radiation energy, and then measure the gamma rays released by the sample under test after neutron activation, and determine the energy of the measured radiation through the detector output signal and the established correspondence.

[0026] Specifically, when the content of the first element is greater than the first element content threshold, its absorption interaction with other elements in the sample being tested is significant, and the standard value cannot be relied upon alone. After extracting the absorption interaction elements, based on the characteristics that the atomic number reflects the difference in the element's ability to absorb radiation, the content affects the strength of the absorption effect, and the radiation energy is related to the degree of absorption attenuation, the product of the standard radiation self-absorption correction coefficient, atomic number, and content of the first element and each absorption interaction element is divided by their respective radiation energies, and then the absorption effects of the first element itself and each absorption interaction element are summed and integrated to comprehensively reflect the actual absorption situation under the synergistic effect of multiple elements, thereby obtaining an accurate radiation self-absorption correction coefficient of the first element.

[0027] It can be understood that the specific steps of collaborative calculation of radiation self-absorption correction coefficients of multiple elements have been refined. By extracting interactive elements and quantitatively calculating them, the absorption effects of multiple elements are comprehensively considered, making the correction of high-content first elements more accurate.

[0028] In some embodiments of the present application, adjusting the flux distribution based on the neutron absorption cross section includes: When the neutron absorption cross section is greater than a neutron absorption cross section threshold, the flux distribution is determined using a Monte Carlo simulation method; When the neutron absorption cross section is less than or equal to a neutron absorption cross section threshold, the flux distribution is equal to a standard flux distribution.

[0029] Specifically, when the neutron absorption cross section is greater than the neutron absorption cross section threshold, the measured sample has a strong absorption effect on neutrons, and the scattering, attenuation and other interaction processes of neutrons in the sample are more complex. At this time, the method based on the simplified assumption of homogeneous medium cannot accurately reflect the actual propagation and distribution of neutrons, while the Monte Carlo simulation method can accurately depict the complex scattering, absorption and other microscopic processes between neutrons and matter by simulating the motion trajectories of a large number of neutrons through random sampling, so as to more reliably determine the flux distribution; the neutron absorption cross section threshold is a cross section value determined by statistically determining the critical value of the neutron absorption cross section that has a significant impact on the flux distribution; the standard flux distribution is the neutron flux distribution data obtained by measuring a standard sample with a known composition under a preset standard experimental condition; the standard flux distribution is obtained by measuring the neutron flux of a standard sample containing no neutron interaction elements or having a content of neutron interaction elements lower than a preset threshold under a preset experimental condition, recording the flux values of neutrons at different positions in the standard sample, and obtaining the flux distribution data after data processing and averaging.

[0030] It can be understood that the flux distribution is determined according to the neutron absorption cross section, the Monte Carlo simulation is used when the cross section is greater than the threshold, and otherwise the standard distribution is used, which takes into account the complex and simple scenarios and improves the rationality of the flux distribution.

[0031] In some embodiments of the present application, when the Monte Carlo simulation method is used to determine the flux distribution, the method comprises: extracting neutron interaction elements in the measured sample that interact with neutrons; obtaining the neutron scattering cross section, the neutron absorption cross section and the content of the neutron interaction elements; dividing the product of the neutron scattering cross section, the neutron absorption cross section and the content of the neutron interaction elements by a preset neutron energy constant to obtain a first distribution parameter; adding the first distribution parameters of each of the neutron interaction elements to obtain a second distribution parameter; substituting the second distribution parameter into a Monte Carlo simulation model to obtain the flux distribution.

[0032] Specifically, the preset neutron energy constant is a constant related to the neutron energy determined by experiment and fixed by referring to the average energy of the actually used neutron source; when extracting the neutron interaction elements in the measured sample that interact with neutrons, first, based on the periodic table of elements, elements with atomic number greater than or equal to a preset threshold (such as Z≥10) are screened out, and the atomic nuclei of these elements have sufficient mass number to have significant scattering or absorption effects with neutrons; then, the measured sample is scanned by an energy dispersive X-ray fluorescence spectrometer (EDXRF) to identify the major and minor elements with a relative content greater than 0.1% as candidate interaction elements. When obtaining the neutron scattering cross section and the neutron absorption cross section of the neutron interaction elements, the standard cross section data of each element in the thermal neutron energy region (0.0253eV) is extracted from the ENDF / B-Ⅷ.0 database published by the International Atomic Energy Agency (IAEA), and for isotopes not included in the database, a theoretical calculation model (such as an optical model potential) is used in combination with experimental data to extrapolate; the element content is measured by neutron activation analysis (NAA) to obtain the characteristic gamma ray peak area, and the calibration curve of the known standard material is used to quantitatively calculate the element content, and for light elements (such as H, C, N), elastic recoil detection analysis (ERDA) is used for supplementary measurement, and finally the element content is normalized to mass percentage.

[0033] Specifically, when the neutron absorption cross section is greater than the threshold value, the interaction between the neutron and the sample is strong and complex, and after extracting the neutron interaction elements, their scattering cross section, absorption cross section and content jointly determine the scattering and absorption behavior of the neutron. The first distribution parameter obtained by multiplying the product of the three by the neutron energy constant can quantify the influence of a single element on the neutron flux, and the second distribution parameter obtained by accumulation can comprehensively reflect the overall effect of all interaction elements. Substituting into the Monte Carlo simulation model can accurately simulate the motion trajectory and distribution rule of the neutron under complex action, thereby obtaining an accurate flux distribution.

[0034] It can be understood that the operation of determining the flux distribution by Monte Carlo simulation is defined, and the flux distribution calculation in a complex scene is more targeted and accurate by extracting the neutron interaction elements and calculating the distribution parameters.

[0035] In some embodiments of the present application, when the peak position is calibrated based on the environmental temperature change amount, it includes: When the environmental temperature change amount is greater than the temperature change threshold, the peak position calibration value is determined by using the temperature segmented calibration method; When the environmental temperature change amount is less than or equal to the temperature change threshold, the peak position calibration value is equal to the standard peak position calibration value.

[0036] Specifically, the temperature change threshold is the minimum temperature change amount determined by statistics of the influence of different temperature change amplitudes on the peak position calibration accuracy, which needs to use the segmented calibration method; the standard peak position calibration value is a fixed peak position calibration value determined based on the standard temperature and the initial measurement condition when the environmental temperature change amount does not exceed the temperature change threshold; the standard peak position calibration value is a peak position calibration value determined by measuring the detector at a preset standard temperature condition using a standard radioactive source with a known energy, obtaining the characteristic peak position data corresponding to the standard radioactive source, and taking the characteristic peak position data as a reference.

[0037] It can be understood that the peak position is calibrated according to the environmental temperature change amount, the segmented calibration is used when the threshold is exceeded, and the standard value is used otherwise, which reduces the influence of temperature fluctuations on the peak position and improves the reliability of the peak position calibration.

[0038] In some embodiments of the present application, when the peak position calibration value is determined by using the temperature segmented calibration method, the method comprises: dividing the environmental temperature into a plurality of continuous temperature intervals; determining the temperature interval to which the current environmental temperature belongs; obtaining the peak position temperature coefficient and the standard peak position value corresponding to the temperature interval; multiplying the peak position temperature coefficient, the difference between the current environmental temperature and the standard temperature, and the standard peak position value to obtain the peak position calibration value.

[0039] Specifically, the peak position temperature coefficient is determined by measuring the peak position offset amount and the temperature change ratio of a standard sample at different temperatures in a specific temperature interval, and is used to quantify the influence of temperature on the peak position; the standard peak position value is a peak position reference value obtained by measuring a standard source ray with a known energy at a standard temperature condition; the standard temperature is a constant temperature value set by experiment as a peak position calibration reference, and is usually the environmental temperature when the detection equipment is calibrated or initially measured; when the peak position temperature coefficient and the standard peak position value corresponding to the temperature interval are obtained, standard samples covering each temperature interval are selected, the characteristic peak position of the standard sample is measured at a plurality of temperature points in each temperature interval, the difference between the peak position at different temperature points and the peak position at the standard temperature is calculated, and the peak position temperature coefficient of the interval is fitted by combining the temperature change amount, and the characteristic peak position measured at the standard temperature is determined as the standard peak position value corresponding to the interval.

[0040] Specifically, when the environmental temperature change is greater than the temperature change threshold, the influence of temperature on the detector presents a nonlinear characteristic, dividing the environmental temperature into several continuous intervals can make the relationship between temperature and peak position shift in each interval approximately linear, by determining the interval to which the current temperature belongs, obtaining the peak position temperature coefficient (reflecting the relative shift amount of the peak position caused by unit temperature change in the interval) corresponding to the interval and the standard peak position value, and then combining the difference between the current environmental temperature and the standard temperature, multiplying the three to quantify the peak position shift caused by temperature change in the interval, thereby obtaining the peak position calibration value.

[0041] It can be understood that the step of refining the temperature segmented calibration peak position divides the interval and quantitatively calculates the calibration value, so that the peak position calibration is more accurate when the temperature changes greatly, and adapts to different temperature environments.

[0042] In some embodiments of the present application, when the background is corrected based on the environmental humidity, comprising: When the environmental humidity is greater than the humidity threshold, the background correction amount is determined by using the humidity dynamic correction method; When the environmental humidity is less than or equal to the humidity threshold, the background correction amount is equal to the standard background correction amount.

[0043] Specifically, the humidity threshold is a humidity value determined by statistics of the critical value of the environmental humidity that has a significant influence on the background noise; the standard background correction amount is a background correction reference value obtained by measuring the background under the condition of a preset humidity without a measured sample; the process of obtaining the standard background correction amount is as follows: under the condition of a preset humidity, ensure that there is no measured sample in the detection environment, use the same PGNAA equipment and parameter settings as the actual detection, measure the background radiation in the environment, obtain the background spectrum data, and then obtain the reference value for subsequent background correction by processing the background spectrum data, such as baseline deduction and noise filtering. The reference value is the standard background correction amount.

[0044] It can be understood that the background is corrected based on the environmental humidity, and the dynamic correction is used when the threshold is exceeded, otherwise the standard value is used, which effectively deals with the influence of humidity change on the background and improves the applicability of the background correction.

[0045] In some embodiments of the present application, when the background correction amount is determined by using the humidity dynamic correction method, comprising: Obtain the initial humidity and the current humidity of the measured sample; Calculate the difference between the current humidity and the initial humidity to obtain the humidity change; Obtain the preset humidity correction coefficient and the standard background spectrum; Multiply the humidity change, the humidity correction coefficient, and the standard background spectrum to obtain the background correction amount.

[0046] Specifically, the initial humidity is an initial value of the environmental humidity recorded at the beginning of detection; the preset humidity correction coefficient is a correction proportional coefficient corresponding to humidity change obtained by fitting the change rule of background noise under different humidity through experimental measurement; the standard background spectrum is background radiation spectrum data obtained by measuring the state of no sample under the preset humidity condition; the preset humidity correction coefficient is obtained by measuring the background noise change corresponding to different humidity through multiple detection of the sample under different humidity conditions, and then calculating the ratio of the background noise change to the humidity change; and the standard background spectrum is obtained by detecting the environment without the sample under the preset standard humidity condition, collecting and recording the background radiation spectrum at the time.

[0047] Specifically, when the environmental humidity is greater than the humidity threshold value, the humidity change will significantly affect the physical state of the sample (such as the change of water content which may change the density and scattering characteristics of the sample) and the scattering background of the environment around the detector (such as the scattering enhancement of water molecules to the rays), and the difference between the initial humidity and the current humidity (the humidity change) directly reflects the degree of such influence, the preset humidity correction coefficient is a proportional coefficient for quantifying the influence of humidity change on the background based on a large amount of experimental data, and the standard background spectrum represents the background radiation level under the benchmark state, so the multiplication of the three can comprehensively quantify the influence of humidity change on the background, and obtain the accurate background correction amount.

[0048] It can be understood that the specific operation of dynamically correcting the background by humidity is determined, the background correction under high humidity environment is more accurate by calculating the humidity change and quantifying the correction, and the humidity interference is reduced.

[0049] It should be noted that: In the specification provided herein, a large number of specific details are described. However, it can be understood that the embodiments of the present application can be practiced without these specific details. In some examples, well-known structures and techniques are not shown in detail in order not to obscure the understanding of the present specification.

[0050] In addition, those skilled in the art can understand that although some embodiments described herein include certain features included in other embodiments but not others, the combination of features of different embodiments means within the scope of the present application and forms different embodiments.

[0051] The above is only the preferred specific implementation of the present application, but the protection scope of the present application is not limited to this. Any changes or replacements easily thought of by those skilled in the art within the technical scope disclosed by the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A comprehensive analysis method for PGNAA detection data, characterized in that: include: S1, obtaining the first element content, neutron absorption cross section, ambient temperature change, and ambient humidity of the sample under test; S2, adjusting the radiation self-absorption correction coefficient of the first element based on the content of the first element; S3, adjusting the flux distribution based on the neutron absorption cross section; S4, calibrating the peak position based on the ambient temperature change; S5, correcting the background based on the ambient humidity.

2. The method for comprehensive analysis of PGNAA detection data according to claim 1, characterized in that: Adjusting the radiation self-absorption correction coefficient of the first element based on the content of the first element includes: When the first element content is greater than the first element content threshold, a multi-element collaborative calculation method is used to determine the radiation self-absorption correction coefficient of the first element; When the first element content is less than or equal to a first element content threshold, the radiation self-absorption correction coefficient of the first element is equal to the standard radiation self-absorption correction coefficient of the first element.

3. A method for comprehensive analysis of PGNAA detection data according to claim 2, characterized in that: When determining the radiation self-absorption correction coefficient of the first element by using a multi-element collaborative calculation method, it includes: extracting an absorption interaction element that has an absorption interaction with the first element in the sample being tested; Obtaining the standard radiation self-absorption correction coefficient, atomic number, content, and radiation energy of the first element and the standard radiation self-absorption correction coefficient, atomic number, content, and radiation energy of each of the absorption interaction elements; The first correction coefficient is obtained by dividing the product of the standard radiation self-absorption correction coefficient, the atomic number, and the content of the first element by the radiation energy of the first element; The second correction coefficient is obtained by dividing the product of the standard radiation self-absorption correction coefficient, the atomic number, and the content of the absorbing interactive element by the radiation energy of the absorbing interactive element; Adding the second correction coefficients of each of the absorption interaction elements to obtain a third correction coefficient; The third correction coefficient and the first correction coefficient are summed to obtain the radiation self-absorption correction coefficient of the first element.

4. A method for comprehensive analysis of PGNAA detection data according to claim 3, characterized in that: When adjusting the flux distribution based on the neutron absorption cross section, it includes: When the neutron absorption cross section is greater than a neutron absorption cross section threshold, the flux distribution is determined using a Monte Carlo simulation method; When the neutron absorption cross section is less than or equal to a neutron absorption cross section threshold, the flux distribution is equal to a standard flux distribution.

5. A method for comprehensive analysis of PGNAA detection data according to claim 4, characterized in that: When the flux distribution is determined by Monte Carlo simulation, it includes: Extracting neutron-interactive elements that interact with neutrons in the sample being tested; Obtaining the neutron scattering cross section, neutron absorption cross section, and content of the neutron interactive element; The first distribution parameter is obtained by dividing the product of the neutron scattering cross section, the neutron absorption cross section, and the content of the neutron interactive element by a preset neutron energy constant; Adding the first distribution parameter of each of the neutron interaction elements to obtain a second distribution parameter; Substituting the second distribution parameter into the Monte Carlo simulation model, the flux distribution is obtained.

6. A method for comprehensive analysis of PGNAA detection data according to claim 5, characterized in that: When calibrating the peak position based on the ambient temperature change, the method includes: When the ambient temperature change is greater than the temperature change threshold, a temperature segmented calibration method is used to determine a peak position calibration value; When the ambient temperature change is less than or equal to a temperature change threshold, the peak position calibration value is equal to a standard peak position calibration value.

7. A method for comprehensive analysis of PGNAA detection data according to claim 6, characterized in that: When using the temperature segmented calibration method to determine the peak position calibration value, it includes: Divide the ambient temperature into several continuous temperature intervals; Determine the temperature range to which the current ambient temperature belongs; Obtaining the peak temperature coefficient and the standard peak value corresponding to the temperature range; The peak position calibration value is obtained by multiplying the peak position temperature coefficient, the difference between the current ambient temperature and the standard temperature, and the standard peak position value.

8. A method for comprehensive analysis of PGNAA detection data according to claim 7, characterized in that: When correcting the background based on the ambient humidity, it includes: When the ambient humidity is greater than the humidity threshold, a background correction amount is determined using a humidity dynamic correction method; When the ambient humidity is less than or equal to the humidity threshold, the background correction amount is equal to the standard background correction amount.

9. A method for comprehensive analysis of PGNAA detection data according to claim 8, characterized in that: When using the humidity dynamic correction method to determine the background correction amount, it includes: Obtaining the initial humidity and current humidity of the sample being tested; Calculate the difference between the current humidity and the initial humidity to get the humidity change; Obtain the preset humidity correction factor and standard background spectrum; The background correction amount is obtained by multiplying the humidity change amount, the humidity correction coefficient, and the standard background spectrum.

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