CN115144886B - High-throughput neutron dose assessment method and device - Google Patents

Abstract

The invention relates to the field of nuclear emergency medical rescue, and provides a high-throughput neutron dose assessment method and device. By performing the conversion calculation from the neutron dose to the surrounding dose equivalent rate in advance, when evaluating the neutron dose of the human body, no The energy spectrometer is used to measure the specific activity of ²⁴ Na in the human body, and the preliminary neutron dose of a person can be realized only by using the radiation survey instrument to measure the surrounding dose equivalent rate at the abdomen position of the human body within a few seconds. Judgment and assessment: Compared with traditional methods, the present invention greatly saves the time for neutron dose assessment, and is especially suitable for scenarios where a large number of personnel need to perform neutron dose assessment and screening after a nuclear disaster.

Description

High-throughput neutron dose assessment method and device

technical field

The invention relates to the field of nuclear emergency medical rescue, and relates to a high-throughput neutron dose assessment method and device.

Background technique

In nuclear explosions and nuclear accidents, neutron external exposure is an important source of human radiation. Therefore, when personnel are exposed to nuclear radiation, timely and accurate assessment of neutron external exposure dose is of great value for the medical treatment of the wounded and the assessment of the degree of accident hazard. Especially in the scenario of a nuclear disaster, a large number of people are exposed to neutrons, and it is necessary to complete the assessment of the severity of the neutron exposure of a large number of people in the shortest possible time, and then proceed according to the severity of the assessment. Targeted treatment, in order to achieve the scientific allocation of medical resources, to avoid the purpose of running out of medical resources.

In the prior art, the amount of ²⁴ Na produced by the reaction of neutrons and ²³ Na elements in the human body is usually used to judge the neutron dose. However, the disadvantages are as follows:

1) It is necessary to measure and analyze the ²⁴ Na content of the human body, the process is complicated, and the measurement of a single person may take tens of minutes, which is time-consuming;

2) The measurement technology is difficult and requires the inspectors to have rich professional knowledge;

3) The measurement requires an expensive energy spectrometer.

Therefore, there is an urgent need for a high-throughput neutron dose assessment method with high measurement efficiency.

Contents of the invention

The present invention provides a high-throughput neutron dose assessment method, device and electronic equipment, which only need to use a simple portable radiation survey instrument to measure the ²⁴ Na-induced radioactive intensity produced by neutron irradiation in the body of the irradiated population. Weakness, to quickly reflect the size of the neutron dose, and then achieve the technical effect of quickly judging the severity of a large number of personnel exposed to neutrons.

In order to achieve the above object, the present invention provides a high-throughput neutron dose assessment method, the method comprising:

Use a radiation measuring instrument to measure the surrounding dose equivalent rate of the person to be detected at a set distance from the abdomen of the human body;

Acquire the distance corresponding to the interval time according to the interval time from the end time of neutron irradiation to the measurement time of the radiation measuring instrument and the pre-acquired surrounding dose equivalent rate at the set distance from the abdomen of the digital model of the human body at the end time of neutron irradiation Ambient dose equivalent rate at a set distance from the abdomen of the digital human model;

Determine whether the neutron dose of the person to be detected is greater than the neutron dose limit according to the surrounding dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time and the actually measured surrounding dose equivalent rate at the set distance from the abdomen of the human body value; where,

When the actual measured ambient dose equivalent rate at the set distance from the abdomen of the human body is greater than the ambient dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time, it is determined that the neutron dose of the person to be detected is greater than the neutron dose limit value .

Further, preferably, the method for obtaining the surrounding dose equivalent rate at a set distance from the abdomen of the digital human body model includes,

Use the preset human body tomographic image data set to establish a digital model of the human body, and obtain the number of pixels of each organ tissue;

Assign corresponding element composition and density value to each organ tissue of the digital human body model, and determine the mass of each organ tissue according to the density value;

Obtain the ²³ Na mass percentage of each organ tissue, and then obtain the ²³ Na atom number of each organ tissue in the digital model of the human body according to the ²³ Na mass percentage of each organ tissue, the organ tissue mass and Avogadro constant;

Use the particle transport simulation program to obtain the neutron fluence of monoenergetic neutrons in each organ and tissue in the human body digital model under the energy E and different irradiation geometric modes, and according to the neutron fluence of each organ tissue in the human body digital model The sub-fluence and the number of ²³ Na atoms, to obtain the ²⁴ Na output of each organ and tissue in the digital model of the human body under the condition of single-energy neutron external irradiation of unit fluence;

Using the particle transport simulation program, set each organ and tissue as a photon source, and set the ²⁴ Na yield in each organ and tissue of the digital model of the human body under the energy E and different irradiation geometry as each organ The photon sampling probability of the photon source of the organization, and the establishment of a human body photon source model with ²⁴ Na content distribution;

Based on the photon source model of the human body with ²⁴ Na content distribution, the particle transport simulation program is used to obtain the photon fluence at the set distance from the abdomen of the digital model of the human body under different irradiation geometries;

Calculate the neutron fluence corresponding to the human neutron dose limit, and according to the neutron fluence corresponding to the human neutron dose limit and the unit fluence single-energy neutron external irradiation ²⁴ Na production obtains the ²⁴ Na activity produced by each organ corresponding to the neutron dose limit of the human body;

According to the photon fluence at the set distance from the abdomen of the digital model of the human body under different irradiation geometric modes and the ²⁴ Na activity produced by each organ corresponding to the neutron dose limit of the human body, the distance from the abdomen of the digital model of the human body to the end time of neutron irradiation is obtained. Ambient dose equivalent rate at distance.

Further, preferably, the method for establishing a digital model of a human body by using a preset human body tomographic image data set, and obtaining the number of pixels of each organ tissue includes,

Starting from the first pixel of the first image of the human body tomographic image dataset, traverse the color value of each pixel of all human tomographic images;

According to the color value C _n (a, b, c) corresponding to each organ tissue, obtain the total number of pixels of each organ tissue; where, a, b, c represent red R, green G, blue Integer component value of color B, and 0≤a≤255, 0≤b≤255, 0≤c≤255; organs and tissues include skin, bone, brain, heart, lung, liver, kidney, spleen, stomach, large intestine, small intestine and muscles;

All the pixel numbers of each organ tissue are accumulated to obtain the pixel number P _n of each organ tissue.

Further, preferably, the number of ²³ Na atoms in each organ and tissue in the human body digital model is obtained according to the ²³ Na mass percentage of each organ tissue, the mass of the organ tissue and Avogadro's constant, and is realized by the following formula:

S _n =M _n ×Y _n (N _a , p)/23×N _A

Among them, S _n represents the number of ²³ Na atoms in each organ and tissue in the digital model of the human body, N _A represents Avogadro’s constant, Y _n (N _a , p) represents the mass percentage of ²³ Na in the organ and tissue; M _n represents organ tissue quality; in addition,

The mass of organs and tissues is obtained by the following formula: M _n = R×P _n ×ρ _n , n∈(1,2,3…T), T is the quantity of organs and tissues, R is the resolution of the human body digital model, and P _n is The number of pixels of organ tissue, ρ _n is the density of each organ tissue.

Further, preferably, according to the neutron fluence and the number of ²³ Na atoms of each organ and tissue in the digital human body model, obtain the ²⁴ Na production of each organ and tissue in the human body digital model under the condition of unit fluence monoenergetic neutron external irradiation. Amount, realized by the following formula,

_Pn (G,E)/Φ(G,E)= _Φn (G,E,ε)×σ(ε)× _Sn ×A

Among them, P _n (G, E)/Φ (G, E) represents the ²⁴ Na output of each organ and tissue in the digital model of the human body under the condition of unit fluence monoenergetic neutron external irradiation; P _n (G, E) represents The number of ²⁴ Na atoms produced by monoenergetic neutrons with energy E under different irradiation geometries in various organs and tissues, Φ(G, E) represents the fluence of neutron sources with energy E under different irradiation geometries; Φ _n (G, E, ε) represents the neutron fluence of each organ and tissue in the digital human body model; σ(ε) represents the cross-section of the capture reaction between neutrons with energy ε and ²³ Na; S _n represents each The number of ²³ Na atoms in an organ or tissue; A represents the cross-sectional area of the neutron source; in addition,

The neutron fluence Φ _n (G, E, ε) of each organ tissue in the digital human body model is obtained by the following formula:

Φ _n (G, E, ε) = L _n /( R×P _n )

G represents the geometry of neutron external radiation, G∈(LLAT, RLAT, AP, PA, ISO), where LLAT represents left lateral radiation, RLAT represents right lateral radiation, AP represents forward radiation, and PA represents backward radiation , ISO means isotropic irradiation; E means the initial monoenergetic neutron energy incident to the human body, ε means the neutron energy of the initial monoenergetic neutron energy entering the organ tissue n after being slowed down by other organs and tissues; L _n Indicates the length of the neutron movement track in the organ tissue, R indicates the resolution of the digital model of the human body, and P _n is the number of pixels in the organ tissue.

Further, preferably, the method of setting each organ tissue as a photon source includes,

Starting from the first pixel of the first image of the human body tomographic image dataset, traverse the color value of each pixel of all human tomographic images;

Screen the pixels whose color value corresponds to the color value of a certain organ tissue, and set the type of emitted particles corresponding to the pixel to photons, and set the probability of emitted particles corresponding to the pixel to unit fluence in the case of single-energy neutron external irradiation of the human body ^24Na production P _n (G, E)/Φ (G, E) of a certain organ tissue in the digital model;

Traversing all the pixels of all the images in the human body tomographic image data set, complete the photon source setting of each organ tissue; wherein, the photon energy in the photon source of each organ tissue is set to 1.369MeV and 2.754MeV.

Further, preferably, the set distance from the abdomen of the digital human body model is the distance d between the radiation measuring instrument and the abdomen of the person to be detected when the radiation measuring instrument is perpendicular to the abdomen surface, and 5 cm≤d≤30 cm.

Further, preferably, the surrounding dose equivalent rate corresponding to the interval time at a set distance from the abdomen of the digital human body model is obtained by the following formula,

Among them, H ^* (G, E) represents the surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval time, and H´(G, E) represents the distance from the abdomen setting of the digital human body model at the end of neutron irradiation The surrounding dose equivalent rate at the distance, e is a constant, and T is the half-life of ²⁴ Na; in addition,

The surrounding dose equivalent rate H´(G,E) at the set distance from the abdomen of the digital model of the human body at the end of neutron irradiation is obtained by the following formula,

表示人体中子剂量限值相对应各个器官产生的²⁴Na活度，

表示 对所有器官的²⁴Na活度累加后获得的人体²⁴Na总活度；F（G，E）表示单能光子单位注量-周围 剂量当量转换系数。Φ _d (G, L) represents the photon fluence at a set distance from the abdomen of the digital human body model under different irradiation geometries,

Indicates that the human neutron dose limit corresponds to the ²⁴ Na activity produced by each organ,

Indicates the total ²⁴ Na activity of the human body obtained after summing up the ²⁴ Na activities of all organs; F(G, E) indicates the conversion coefficient of monoenergetic photon unit fluence-surrounding dose equivalent.

In order to solve the above problems, the present invention also provides a high-throughput neutron dose assessment device, which includes:

The radiation measuring instrument measurement module is used to measure the surrounding dose equivalent rate at the set distance from the abdomen of the human body of the person to be detected by using the radiation measuring instrument;

The judgment threshold acquisition module is used to obtain the surrounding dose equivalent rate at the set distance from the abdomen of the digital model of the human body according to the interval time between the end time of the neutron irradiation of the person to be detected and the measurement time of the radiation measuring instrument and the pre-acquired neutron irradiation end time. , to obtain the surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval time;

The judging module is used to determine whether the neutron dose of the person to be detected is greater than the neutron dose limit; where,

When the actual measured ambient dose equivalent rate at the set distance from the abdomen of the human body is greater than the ambient dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time, it is determined that the neutron dose of the person to be detected is greater than the neutron dose limit value.

In order to solve the above problems, the present invention also provides an electronic device, which includes:

a memory storing at least one instruction; and

A processor, executing the instructions stored in the memory to implement the steps in the above-mentioned high-throughput neutron dose assessment method.

The beneficial effects of the high-throughput neutron dose assessment method, device and electronic equipment of the present invention are as follows,

1) Due to the calculation of the conversion from neutron dose to ambient dose equivalent rate in advance, when evaluating the neutron dose to the human body, it is not necessary to use the energy spectrometer to measure the specific activity of ²⁴ Na in the human body, but only need to use radiation The survey instrument measures the surrounding dose equivalent rate of the abdomen position of the human body in a few seconds, and can realize the preliminary judgment and evaluation of the neutron dose of a person; compared with the traditional method, the present invention greatly saves the cost of neutron dose assessment. Time, especially suitable for scenarios where a large number of personnel need to undergo neutron dose assessment and screening after a nuclear disaster;

2) The neutron dose assessment method of the present invention is quick and convenient, and the radiation survey instrument has simple functions and can be operated by non-professionals. Therefore, a large number of personnel can be allocated to carry out neutron dose assessment and screening work, which requires more than traditional methods. This method realizes high-throughput screening, greatly improves the efficiency of neutron dose assessment, and has very important social and economic benefits.

3) Compared with the neutron dose assessment using the energy spectrometer in the prior art, the present invention uses a cheap portable radiation survey instrument, which can be configured in large quantities, thereby greatly improving the detection efficiency on the basis of reducing the detection cost .

Description of drawings

Fig. 1 is a schematic flow chart of a high-throughput neutron dose assessment method provided by an embodiment of the present invention;

Fig. 2 is a schematic diagram of the principle of particle external irradiation geometric conditions provided by an embodiment of the present invention;

Fig. 3 is a schematic diagram of a scene in which a radiation survey instrument is used to measure the dose equivalent rate around the abdomen of a human body according to an embodiment of the present invention;

4 is a schematic diagram of the principle of a high-throughput neutron dose assessment device provided by an embodiment of the present invention;

Fig. 5 is a schematic diagram of the internal structure of electronic equipment for implementing a high-throughput neutron dose assessment method provided by an embodiment of the present invention;

The realization of the purpose of the present invention, functional characteristics and advantages will be further described in conjunction with the embodiments and with reference to the accompanying drawings.

detailed description

It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Referring to FIG. 1 , it is a schematic flowchart of a high-throughput neutron dose assessment method provided by an embodiment of the present invention. The method may be performed by a device, and the device may be implemented by software and/or hardware.

In this embodiment, the high-throughput neutron dose assessment method includes steps S1-S3.

S1. Using a radiation measuring instrument to measure the surrounding dose equivalent rate of the person to be detected at a set distance from the abdomen of the human body.

It should be noted that the radiation survey instrument, the full name of the ionizing radiation survey instrument, generally uses NaI(T _l ) crystal or GM tube as the detector, and is equipped with an electronic amplification circuit and an alarm indicating device, which is regarded as an ionizing radiation survey instrument. meter. Typical levels of gamma (γ) radiation can be detected. Generally, under the normal background level, if the radiation level doubles, common radiation survey instruments can clearly detect it. For example, after the Japanese nuclear leak, the radiation survey instrument can detect it. The unit of measurement is uSv/h.

S2. According to the interval time from the end of neutron irradiation to the measurement time of the radiation measuring instrument and the pre-acquired surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model, obtain the distance corresponding to the interval time from the digital human body model. Peripheral dose equivalent rate at a set distance from the abdomen.

The method for obtaining the surrounding dose equivalent rate at a set distance from the abdomen of the digital human body model includes steps S21-S28.

S21. Establish a digital model of a human body by using a preset human body tomographic image data set, and obtain the number of pixels of each organ tissue.

It should be noted that it is necessary to use the preset human tomographic image data set to establish a digital model of the human body to represent the population subjected to external neutron irradiation. The human tomographic image dataset includes sequential tomographic images of the human body. The number of human body sequence tomographic images is k, the thickness between human body sequence tomographic images is i, and i≤0.2 cm; the pixel resolution of sequence tomographic images is j×j, and j×j≤0.1 cm×0.1 cm. First of all, it is necessary to obtain high-quality sequential tomographic images of the human body; such as CT pictures, MRI or color anatomical pictures; it should be noted that the number of original tomographic images is k, and the size of k should be able to include the whole body of the human body, not just a part of the body. Then, the sequential tomographic images of the human body are preprocessed to generate a three-dimensional digital model. The digital model can be a voxel model, etc.; but not limited to, Matlab7.0 and Photoshop8.0 image processing software can be used to process the sequence tomographic images of the human body.

In addition, in the process of establishing the digital model of the human body, it is necessary to identify and segment the organs and tissues in the tomographic images. The organs and tissues that need to be identified include at least: skin, bones, brain, heart, lungs, liver, kidneys, spleen, and stomach Organs that mainly contain ²³ Na, such as the large intestine, small intestine, and muscle, and unrecognized tissues were replaced by muscle. The total number of organs and tissues is represented by T.

After identifying and segmenting the organs and tissues in the tomographic image, the different organs and tissues identified in the tomographic image are filled with different colors, and the filled color value is C _n (a, b, c), where n∈ (1,2,3...T), T is the number of organs and tissues, a, b, c respectively represent the integer component values of red R, green G, and blue B in the RGB color space, and 0≤a≤255, 0≤b≤255, 0≤c≤255. For example muscles are filled with color values C1 (10, 79, 210) and bones are filled with color values C2 (130, 0, 75).

In a specific embodiment, the method for establishing a digital model of a human body by using a preset human body tomographic image data set, and obtaining the number of pixels P _n of each organ tissue, n∈(1,2,3...T) includes: S211 , starting from the first pixel of the first image of the human body tomographic image data set, traverse the color value of each pixel of all human body tomographic images; S212, according to the color value C _n (a, b, c) Obtain the total number of pixels of each organ tissue; wherein, the organ tissue includes skin, bone, brain, heart, lung, liver, kidney, spleen, stomach, large intestine, small intestine, and muscle; S113. All the pixel numbers are accumulated to obtain the pixel number P _n of each organ tissue. That is to say, if the color value belongs to a certain organ tissue C _n (a, b, c), the pixels of this organ tissue are accumulated until the number of pixels P _n of this organ tissue is obtained, and then each organ tissue is Do so.

S22. Assign corresponding element composition and density value to each organ tissue of the digital human body model, and determine the mass of each organ tissue according to the density value. In other words, it is necessary to assign physical attributes to the digital model of the human body.

Specifically, for different organ tissues, different element compositions and density values are assigned. The element composition of organ tissue is represented by Y _n {(e ₁ , p ₁ ), (e ₂ , p ₂ ), (e ₃ , p ₃ ),…(e _i , p _i )}, where n∈(1, 2,3...T), e _i represents a certain chemical element, p _i represents the mass percentage of the chemical element, and p ₁ +p ₂ +p ₃ ...+p _i =1. The density of each organ is ρ _n , n∈(1, 2, 3...T). For example, the physical properties of muscle are: Y ₁ {(C, 32%), (H, 45%), (O, 22%), (N, 1%)}, and its density value is ρ ₁ =1.04 g cm ^{- 3} ; The ²³ Na mass percentage of a certain organ tissue is expressed as Y _n (Na, p). Among them, the elemental composition and density values of the digital model of the human body are taken from the International Commission on Radiation Units and Measurements (ICRU) 44 and ICRU 46 reports.

The mass of organs and tissues is obtained by the following formula: M _n = R×P _n ×ρ _n , n∈(1,2,3…T), T is the quantity of organs and tissues, R is the resolution of the human body digital model, and P _n is The number of pixels of organ tissue, ρ _n is the density of each organ tissue. It should be noted that R is the resolution of the digital model of the human body in cm ³ , which is expressed as the volume of a small cube, the smaller the volume, the higher the resolution; R is determined by the pixel resolution of the tomographic image used and The distance between two adjacent tomographic images is determined.

S23. Obtain the ²³ Na mass percentage of each organ tissue, and then obtain the ²³ Na atom number of each organ tissue in the digital model of the human body according to the ²³ Na mass percentage of each organ tissue, the organ tissue mass and Avogadro constant .

According to the mass percentage of ²³ Na in each organ tissue, the mass of the organ tissue and Avogadro's constant, the number of ²³ Na atoms in each organ tissue in the digital human body model is obtained through the following formula:

S _n =M _n ×Y _n (Na,p)/23×N _A

Among them, S _n represents the number of ²³ Na atoms in each organ and tissue in the digital model of the human body, n∈(1,2,3…T), N _A represents Avogadro’s constant, Y _n (Na, p) represents ^23Na mass percentage of organ tissue; M _n represents mass of organ tissue.

S24. Use the particle transport simulation program to obtain the neutron fluence of monoenergetic neutrons in each organ and tissue in the digital human body model with energy E and different irradiation geometry, and obtain the neutron fluence of each organ and tissue in the digital human body model The neutron fluence and the number of ²³ Na atoms are used to obtain the ²⁴ Na production of each organ and tissue in the digital model of the human body under the condition of monoenergetic neutron external irradiation of unit fluence. That is to say, calculate the ²⁴ Na output of various organs and tissues of the human body under the condition of unit fluence monoenergetic neutron external irradiation.

Fig. 2 is a schematic diagram of the principle of particle external irradiation geometric conditions provided by an embodiment of the present invention; as shown in Fig. (AP), backward (PA), isotropic (ISO) irradiation, that is, G∈(LLAT, RLAT, AP, PA, ISO).

The neutron fluence Φ _n (G, E, ε) of each organ tissue in the digital human body model is obtained by the following formula:

Φ _n (G, E, ε) = L _n /( R×P _n )

That is to use the particle transport simulation program to calculate the neutron fluence Φ _n (G, E, ε) of a single neutron in each organ and tissue of the human body under the energy E and different irradiation geometric modes; The neutron track length divided by the volume of organ tissue n; G represents the geometrical mode of neutron external irradiation, G∈(LLAT, RLAT, AP, PA, ISO), E represents the initial monoenergetic neutron energy incident on the human body, ε represents the neutron energy of the initial monoenergetic neutron energy entering the organ tissue n after being slowed down by other organs and tissues; L _n represents the length of the neutron movement track in the organ tissue, R represents the resolution of the digital model of the human body, P _n is the number of pixels of the organ tissue. The main idea of calculating Φ _n (G, E, ε) is to track and record the movement process of neutrons in a certain organ tissue n of the human body, and calculate the length L _n of the neutron movement track in the organ tissue.

That is to say, if you want to obtain the neutron fluence Φ _n (G, E, ε) of each organ and tissue in the digital model of the human body, you need to calculate the neutron movement track length L _n in the organ and tissue first; the specific method is: When the incident neutron i enters the boundary of a certain organ tissue n, record the state of the neutron at the moment, denoted by Par(i) (v ₀ , t ₀ ), where v ₀ , t ₀ respectively represent entering a certain organ tissue The initial velocity and initial moment of the neutron at the n boundary; when the neutron leaves the n boundary of an organ or tissue, use Par´(i)(v´, t´) to represent the state of the neutron at the moment, and v´ and t´ respectively represent The neutron's departure velocity and departure time; the state of the neutron at any moment in the movement of the organ tissue n is expressed as Par(i) (v, t).

Then the calculation method of L _n is:

In the specific implementation process, the energy E of the initial monoenergetic neutrons is respectively set as: 0.01, 0.015, 0.02, 0.03, 0.04, 0.05, 0.06, 0.08, 0.1, 0.15, 0.2, 0.3, 0.4, 0.5, 0.6, 0.8 , 1, 2, 4, 6, 8, 10MeV, 11MeV, 12MeV, 13MeV, 14MeV, 15MeV, 16MeV, 17MeV, 18MeV, 19MeV, 20MeV to cover the common neutron energy range.

Finally, according to the neutron fluence and the number of ²³ Na atoms in each organ and tissue in the digital model of the human body, the ²⁴ Na output of each organ and tissue in the digital model of the human body is obtained under the condition of monoenergetic neutron external irradiation per unit fluence, through The following formula implements,

_Pn (G,E)/Φ(G,E)= _Φn (G,E,ε)×σ(ε)× _Sn ×A

Among them, P _n (G, E)/Φ (G, E) represents the ²⁴ Na production of each organ and tissue in the digital model of the human body under the condition of unit fluence monoenergetic neutron external irradiation; that is, it means different irradiation geometry The ²⁴ Na production of each organ and tissue under the neutron irradiation with unit fluence of energy E. Among them, P _n (G, E) represents the number of ²⁴ Na atoms produced by monoenergetic neutrons with energy E under different irradiation geometries; Φ(G, E) represents the number of 24 Na atoms with energy E under different irradiation geometries The fluence of the neutron source; Φ _n (G, E, ε) represents the neutron ^fluence of each organ and tissue in the digital model of the human body; Cross-section; S _n represents the number of ²³ Na atoms in each organ and tissue in the digital model of the human body; A represents the cross-sectional area of the neutron source, in cm ² .

S25. Using the particle transport simulation program, set each organ and tissue as a photon source, and set the ²⁴ Na yield in each organ and tissue of the human body digital model for monoenergetic neutrons with energy E and different irradiation geometry as The photon sampling probability of the photon sources of various organs and tissues is used to establish a human photon source model with ²⁴ Na content distribution. That is to say, using the particle transport program, according to the ²⁴ Na yield of each organ and tissue calculated in step S24, each organ and tissue of the human body is set as a photon source, and the photon sampling probabilities of each organ and tissue photon source are respectively P _n (G ,E)/Φ(G,E).

The method for setting each organ tissue as a photon source includes: S251, starting from the first pixel of the first image of the human body tomographic image data set, traversing the color value of each pixel of all human tomographic images; S252, screening the color The value is the pixel corresponding to the color value of a certain organ tissue, and the type of emitted particles corresponding to the pixel is set to photon, and the probability of emitting particles corresponding to the pixel is set to the digital model of the human body in the case of single-energy neutron external irradiation The ²⁴ Na yield Pn(G, E)/Φ(G, E) of a certain organ tissue; that is, the organ tissue is set as the photon source; S253, traverse all the pixels of all the images in the human body tomographic image data set, and complete each organ The photon source setting of the tissue; wherein, the photon energy in each organ tissue photon source is set to 1.369MeV and 2.754MeV, and the sampling ratio of the two energies is 1:1.

S26. Based on the photon source model of the human body with ²⁴ Na content distribution, the particle transport simulation program is used to obtain the photon fluence at a set distance from the abdomen of the digital human body model under different irradiation geometric modes.

Firstly, calculate the photon fluence Φ _d (G, L) at the set distance dcm from the abdomen of the digital human body model, based on the human body model with ²⁴ Na content distribution in the body established in step S25, use the particle transport simulation program to calculate the different irradiation The photon fluence at a certain distance d cm from the abdomen of the mannequin in a geometric manner is represented by Φ _d (G, L); its meaning is the photon fluence caused by a photon produced by the decay of ²⁴ Na in the human body at a certain distance d cm from the mannequin abdomen . Among them, G is the geometry of neutron external irradiation, G ∈ (LL, RL, AP, PA, ISO), L represents the remaining photon energy after the photon emitted from the decay of ²⁴ Na in the body, L ∈ (0.01MeV, 0.015 MeV, 0.02 MeV, 0.03 MeV, 0.04 MeV, 0.05MeV, 0.06 MeV, 0.08MeV, 0.1MeV, 0.2MeV, 0.3MeV, 0.4MeV, 0.5MeV, 0.6MeV, 0.7MeV, 0.8MeV, 0.9MeV, 1MeV, 1.5 MeV, 2MeV, 2.5MeV, 2.8MeV).

The calculation method of Φ _d (G, L) is: at a certain distance d cm from the abdomen, set a small sphere with d cm as the center point and a radius of r, record and accumulate the number N of photons entering the small sphere from all directions of the human body _p , then Φ _d (G, L) = N _p /(πr ² ), the setting rule for r is: 0.01 cm≤r≤0.05 cm.

S27. Calculate the neutron fluence corresponding to the neutron dose limit of the human body, and according to the neutron fluence corresponding to the neutron dose limit of the human body and the single-energy neutron external irradiation of the unit fluence, each organ tissue in the digital model of the human body The ²⁴ Na production obtains human neutron dose limits corresponding to the ²⁴ Na activity produced by each organ.

Calculate the human neutron dose limit H corresponding to the ²⁴ Na activity B _n (G, E) produced by each organ. In order to quickly conduct preliminary judgment and screening on the severe neutron exposure of a large number of people, the range of H is set to: 50mSv≤H≤200mSv, which is the neutron dose screening limit; (ICRP74) reports the unit neutron fluence-effective dose conversion coefficient C (G, E), calculates the neutron fluence corresponding to the neutron dose H, expressed by Φ´(G, E); where, G∈ (LL, RL, AP, PA, ISO), E represents the initial monoenergetic neutron energy incident on the human body; the calculation method of Φ´(G, E) is: Φ´(G, E)=H/C(G , E).

Using the ²⁴ Na yield P _n (G, E)/Φ (G, E) calculated in step S24, use the following formula to calculate the ²⁴ Na atomic number Q _n (G, E) of each organ corresponding to H;

Qn(G,E)= _Pn (G,E)/Φ(G,E)× _Φ´ (G,E).

Finally, further use the following formula to calculate the ²⁴ Na activity produced by each organ corresponding to the neutron dose size H in the human body, expressed by B _n (G, E).

B _n (G, E)=0.693/T×Q _n (G, E)

Among them, T is the half-life of ²⁴ Na.

S28. According to the photon fluence at the set distance from the abdomen of the digital model of the human body under different irradiation geometric modes and the neutron dose limit of the human body corresponding to the ²⁴ Na activity produced by each organ, obtain the distance from the digital model of the human body at the end of neutron irradiation Peripheral dose equivalent rate at a set distance from the abdomen.

The surrounding dose equivalent rate H´(G,E) at the set distance from the abdomen of the digital human body model at the end of neutron irradiation is obtained by the following formula:

表示人体中子剂量限值相对应各个器官产生的²⁴Na活度，

表示对所有器官的²⁴Na活度累加后获得的人体²⁴Na总活度；F（G，E）表示单 能光子单位注量-周围剂量当量转换系数，该系数取自ICRP74号报告。需要说明的是，由于²⁴Na一次衰变放出2个光子，因此，

要乘以系数2。 Among them, Φ _d (G, L) represents the photon fluence at the set distance dcm from the abdomen of the digital model of the human body under different irradiation geometries,

Indicates that the human neutron dose limit corresponds to the ²⁴ Na activity produced by each organ,

Indicates the total ²⁴ Na activity of the human body obtained after summing up the ²⁴ Na activities of all organs; F(G, E) indicates the monoenergetic photon unit fluence-surrounding dose equivalent conversion coefficient, which is taken from ICRP74 report. It should be noted that, since ²⁴ Na decays once and emits 2 photons, therefore,

To be multiplied by a factor of 2.

S3. According to the surrounding dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time and the actually measured surrounding dose equivalent rate at the set distance from the abdomen of the human body, determine whether the neutron dose of the person to be detected is greater than the neutron dose Dose limit value; wherein, when the actual measured ambient dose equivalent rate at the set distance from the abdomen of the human body is greater than the ambient dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time, it is determined that the neutron dose of the person to be detected The dose is greater than the neutron dose limit.

Fig. 3 is a schematic diagram of a scene where a radiation survey instrument is used to measure the dose equivalent rate around the abdomen of a human body according to an embodiment of the present invention; Equivalent rate. The set distance from the abdomen of the human body is the distance d between the radiation measuring instrument and the abdomen of the person to be detected when the radiation measuring instrument is perpendicular to the abdominal surface, and 5 cm≤d≤30 cm. distance.

That is to say, according to the interval time t from the end of neutron irradiation to the measurement time of the radiation measuring instrument and the surrounding dose equivalent rate H´(G, E) at a distance d cm from the abdomen of the digital model of the human body, the interval time is obtained The corresponding surrounding dose equivalent rate H*(G, E) at the distance d cm from the abdomen of the digital human model; the corresponding surrounding dose equivalent rate H*(G, E) at the distance d cm from the abdomen of the digital human model according to the interval time and the actual measured ambient dose equivalent rate M(G, E) at a distance d cm from the abdomen of the human body, to determine whether the neutron dose of the person to be detected is greater than the neutron dose limit value H; where, when the distance d cm from the abdomen of the human body When the surrounding dose equivalent rate M(G, E) of the corresponding interval time is greater than the surrounding dose equivalent rate H*(G, E) corresponding to the distance d cm from the abdomen of the digital model of the human body, it is determined that the neutron dose of the person to be detected is greater than the neutron dose Limit value H.

Assuming that the personnel are measured after t seconds after the end of the neutron irradiation, the surrounding dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time is obtained by the following formula:

Among them, H ^* (G, E) represents the surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval time, and H´(G, E) represents the distance from the abdomen setting of the digital human body model at the end of neutron irradiation The surrounding dose equivalent rate at distance, e is a constant, its value is 2.7183, T is the half-life of ²⁴ Na.

When M(G,E)≤H*(G,E), it means that the neutron dose of the person is ≤neutron dose limit H, and it is judged that the person does not need medical treatment; when M(G,E)>H* (G, E), indicating that the neutron dose of the person is greater than the neutron dose limit value H, and the person needs further medical treatment; thus, rapid neutron dose assessment and screening of the person can be realized.

It should be noted that, in the specific implementation process, when the neutron irradiation geometry of the measured person cannot be determined, the ISO irradiation geometry is adopted.

In the high-throughput neutron dose evaluation method of the present invention, since the conversion calculation of the neutron dose to the surrounding dose equivalent rate is carried out in advance, when evaluating the neutron dose of the human body, it is not necessary to use the ratio of ²⁴ Na to the human body by an energy spectrometer. The neutron dose of a person can be initially judged and evaluated by using a radiation survey instrument to measure the surrounding dose equivalent rate at the abdomen of the human body within a few seconds; compared with the traditional method, this The invention greatly saves the time for neutron dose assessment, and is especially suitable for scenarios where a large number of personnel need to conduct neutron dose assessment and screening after a nuclear disaster; The function is simple and can be operated by non-professionals, so a large number of personnel can be allocated for neutron dose assessment and screening. Compared with traditional methods that require professionals to operate, this method achieves high-throughput screening and greatly improves The efficiency of neutron dose assessment has very important social and economic benefits. Compared with the neutron dose assessment using the energy spectrometer in the prior art, the present invention uses a cheap portable radiation survey instrument, which can be configured in large quantities, thereby greatly improving the detection efficiency on the basis of reducing the detection cost.

As shown in FIG. 4 , the present invention provides a high-throughput neutron dose assessment device 400 , which can be installed in electronic equipment. According to the functions realized, the high-throughput neutron dose assessment device 400 may include a radiometer measurement module 410 , a decision threshold acquisition module 420 and a decision module 430 . The module in the present invention can also be called a unit, which refers to a series of computer program segments that can be executed by the processor of the electronic device and can complete fixed functions, and are stored in the memory of the electronic device.

In this embodiment, the functions of each module/unit are as follows:

The radiation measuring instrument measurement module 410 is used to measure the surrounding dose equivalent rate of the person to be detected at a set distance from the abdomen of the human body by using the radiation measuring instrument;

Judgment threshold acquisition module 420, which is used to obtain the surrounding dose equivalent at a set distance from the abdomen of the digital model of the human body according to the interval time between the end time of the neutron irradiation of the person to be detected and the measurement time of the radiation measuring instrument and the pre-acquired neutron irradiation end time Rate, obtain the surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval time;

The determination module 430 is used to determine the neutron dose of the person to be detected according to the surrounding dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time and the actually measured surrounding dose equivalent rate at the set distance from the abdomen of the human body Is it greater than the neutron dose limit value; where,

When the actual measured ambient dose equivalent rate at the set distance from the abdomen of the human body is greater than the ambient dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time, it is determined that the neutron dose of the person to be detected is greater than the neutron dose limit value.

Since the high-throughput neutron dose evaluation device 400 of the present invention has carried out the conversion calculation from the neutron dose to the surrounding dose equivalent rate in advance, when evaluating the neutron dose to the human body, it is not necessary to use the ratio of the energy spectrometer to the human body ²⁴ Na The neutron dose of a person can be initially judged and evaluated by using a radiation survey instrument to measure the surrounding dose equivalent rate at the abdomen of the human body within a few seconds; compared with the traditional method, this The invention greatly saves the time for neutron dose assessment, and is especially suitable for scenarios where a large number of personnel need to conduct neutron dose assessment and screening after a nuclear disaster; The function is simple and can be operated by non-professionals, so a large number of personnel can be allocated for neutron dose assessment and screening. Compared with traditional methods that require professionals to operate, this method achieves high-throughput screening and greatly improves The efficiency of neutron dose assessment has very important social and economic benefits. Compared with the neutron dose assessment using the energy spectrometer in the prior art, the present invention uses a cheap portable radiation survey instrument, which can be configured in large quantities, thereby greatly improving the detection efficiency on the basis of reducing the detection cost.

As shown in FIG. 5 , the present invention provides an electronic device 5 for a high-throughput neutron dose assessment method.

The electronic device 5 may include a processor 50 , a memory 51 and a bus, and may also include a computer program stored in the memory 51 and operable on the processor 50 , such as a high-throughput neutron dose assessment program 52 .

Wherein, the memory 51 includes at least one type of readable storage medium, and the readable storage medium includes flash memory, mobile hard disk, multimedia card, card-type memory (for example: SD or DX memory, etc.), magnetic memory, magnetic disk, CD etc. The memory 51 may be an internal storage unit of the electronic device 3 in some embodiments, such as a mobile hard disk of the electronic device 5 . The memory 31 can also be an external storage device of the electronic device 5 in other embodiments, such as a plug-in mobile hard disk equipped on the electronic device 3, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, flash memory card (Flash Card), etc. Further, the memory 51 may also include both an internal storage unit of the electronic device 5 and an external storage device. The memory 51 can not only be used to store application software and various data installed in the electronic device 5, such as the code of the high-throughput neutron dose assessment program, but also can be used to temporarily store the data that has been output or will be output.

In some embodiments, the processor 50 may be composed of an integrated circuit, for example, may be composed of a single packaged integrated circuit, or may be composed of multiple integrated circuits with the same function or different functions, including one or more Combination of central processing unit (Central Processing unit, CPU), microprocessor, digital processing chip, graphics processor and various control chips, etc. The processor 50 is the control core (Control Unit) of the electronic device, and uses various interfaces and lines to connect various components of the entire electronic device, and runs or executes programs or modules stored in the memory 51 (such as high Flux neutron dose assessment program, etc.), and call the data stored in the memory 51 to execute various functions of the electronic device 5 and process data.

The bus may be a peripheral component interconnect (PCI for short) bus or an extended industry standard architecture (EISA for short) bus or the like. The bus can be divided into address bus, data bus, control bus and so on. The bus is configured to realize connection and communication between the memory 51 and at least one processor 50 and the like.

Figure 5 only shows an electronic device with components, and those skilled in the art can understand that the structure shown in Figure 5 does not constitute a limitation to the electronic device 5, and may include fewer or more components than those shown in the illustration. components, or combinations of certain components, or different arrangements of components.

For example, although not shown, the electronic device 5 may also include a power supply (such as a battery) for supplying power to various components. Preferably, the power supply may be logically connected to the at least one processor 50 through a power management device, so that through power management The device implements functions such as charge management, discharge management, and power consumption management. The power supply may also include one or more DC or AC power supplies, recharging devices, power failure detection circuits, power converters or inverters, power status indicators and other arbitrary components. The electronic device 3 may also include various sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be repeated here.

Further, the electronic device 5 may also include a network interface. Optionally, the network interface may include a wired interface and/or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which are usually used in the electronic device 3 Establish a communication connection with other electronic devices.

Optionally, the electronic device 5 may further include a user interface. The user interface may be a display (Display) or an input unit (such as a keyboard (Keyboard)). Optionally, the user interface may also be a standard wired interface or a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode, organic light-emitting diode) touch device, and the like. Wherein, the display may also be appropriately referred to as a display screen or a display unit, and is used for displaying information processed in the electronic device 5 and for displaying a visualized user interface.

It should be understood that the embodiments are only for illustration, and are not limited by the structure in terms of the scope of the patent application.

The high-throughput neutron dose assessment program 52 stored in the memory 51 in the electronic device 5 is a combination of multiple instructions. When running in the processor 50, it can be realized: use a radiation measuring instrument to measure the dose of the person to be detected The surrounding dose equivalent rate at the set distance from the abdomen of the human body; the interval time from the end of neutron irradiation to the measurement time of the radiation measuring instrument and the pre-acquired surrounding dose at the set distance from the abdomen of the digital model of the human body Equivalent rate, obtain the surrounding dose equivalent rate at the set distance from the abdomen of the digital model of the human body corresponding to the interval time; according to the surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval time and the set distance from the abdomen of the human body The actual measured ambient dose equivalent rate, to determine whether the neutron dose of the person to be detected is greater than the neutron dose limit value; wherein, when the actual measured ambient dose equivalent rate at the set distance from the abdomen of the human body is greater than the distance corresponding to the interval time When the surrounding dose equivalent rate at the set distance from the abdomen of the digital model is determined, it is determined that the neutron dose of the person to be detected is greater than the neutron dose limit value.

Specifically, for the specific implementation method of the above instructions by the processor 50, reference may be made to the description of relevant steps in the embodiment corresponding to FIG. 1 , and details are not repeated here. It should be emphasized that, in order to further ensure the privacy and security of the above-mentioned high-throughput neutron dose assessment program, the above-mentioned database can store the processed data in the nodes of the blockchain where the server cluster is located.

Further, if the integrated modules/units of the electronic device 5 are realized in the form of software function units and sold or used as independent products, they can be stored in a computer-readable storage medium. The computer readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, removable hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory) .

An embodiment of the present invention also provides a computer-readable storage medium, the storage medium may be non-volatile or volatile, the storage medium stores a computer program, and the computer program is executed by a processor Timely implementation: use radiation measuring instrument to measure the surrounding dose equivalent rate of the person to be detected at a set distance from the abdomen of the human body; according to the interval time between the end time of the person to be detected being exposed to neutrons and the time of receiving the measurement of the radiation measuring instrument and the pre-acquired distance The surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model is obtained, and the surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval time is obtained; the surrounding dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval time The dose equivalent rate and the actual measured surrounding dose equivalent rate at the set distance from the abdomen of the human body are used to determine whether the neutron dose of the person to be detected is greater than the neutron dose limit value; When the ambient dose equivalent rate is greater than the ambient dose equivalent rate at the set distance from the abdomen of the digital human body model corresponding to the interval, it is determined that the neutron dose of the person to be detected is greater than the neutron dose limit value.

Specifically, for the specific implementation method when the computer program is executed by the processor, reference may be made to the description of relevant steps in the high-throughput neutron dose assessment method in the embodiment, and details are not repeated here.

In the several embodiments provided by the present invention, it should be understood that the disclosed devices, devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation.

The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional module in each embodiment of the present invention may be integrated into one processing unit, or each unit may physically exist separately, or two or more units may be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware, or in the form of hardware plus software function modules.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention.

Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

The block chain referred to in the present invention is a new application mode of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm. Blockchain (Blockchain), essentially a decentralized database, is a series of data blocks associated with each other using cryptographic methods. Each data block contains a batch of network transaction information, which is used to verify its Validity of information (anti-counterfeiting) and generation of the next block. The blockchain can include the underlying platform of the blockchain, the platform product service layer, and the application service layer.

In addition, it is obvious that the word "comprising" does not exclude other elements or steps, and the singular does not exclude the plural. A plurality of units or means stated in the device claims may also be realized by one unit or device through software or hardware. Secondary terms are used to denote names without implying any particular order.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be Modifications or equivalent replacements can be made without departing from the spirit and scope of the technical solutions of the present invention.

Claims (9)

1. A high-throughput neutron dose assessment method, characterized in that the method comprises:

measuring the peripheral dose equivalent rate of a person to be detected at a set distance from the abdomen of the human body by using a radiation survey meter;

according to the interval time from the neutron irradiation ending time to the radiation inspection instrument measuring time of a person to be detected and the pre-acquired peripheral dose equivalent rate at the set distance from the neutron irradiation ending time to the human digital model abdomen, acquiring the peripheral dose equivalent rate at the set distance from the human digital model abdomen corresponding to the interval time;

judging whether the neutron dose of the person to be detected is greater than a neutron dose limit value or not according to the peripheral dose equivalent rate at the set distance from the human digital model abdomen corresponding to the interval time and the actually measured peripheral dose equivalent rate at the set distance from the human abdomen; wherein,

when the actually measured peripheral dose equivalent rate at the set distance from the human abdomen is greater than the peripheral dose equivalent rate at the set distance from the human digital model abdomen corresponding to the interval time, determining that the neutron dose of the person to be detected is greater than the neutron dose limit value;

the method for acquiring the peripheral dose equivalent rate at the set distance from the neutron irradiation ending time to the human digital model abdomen comprises the following steps,

establishing a human body digital model by using a preset human body tomography image data set, and acquiring the pixel number of each organ tissue;

assigning corresponding element compositions and density values to the organ tissues of the human digital model, and determining the mass of each organ tissue according to the density values;

obtaining tissue of each organ ²³ Na by mass percent, further according to each organ tissue ²³ Obtaining Na mass percentage, organ tissue mass and Avogastron constant of each organ tissue in human digital model ²³ The number of Na atoms;

obtaining neutron fluence of monoenergetic neutrons under different irradiation geometric modes in each organ tissue in the human digital model with energy of E by using a particle transport simulation program, and obtaining the neutron fluence of the monoenergetic neutrons in each organ tissue in the human digital model according to the neutron fluence sum of each organ tissue in the human digital model ²³ The number of Na atoms is obtained, and the number of each organ tissue in the human body digital model under the condition of external irradiation of unit-fluence single-energy neutrons is obtained ²⁴ Na yield;

setting each organ tissue as photon source by utilizing particle transport simulation program, and arranging monoenergetic neutrons with energy of E and different irradiation geometric modes in each organ tissue in human digital model ²⁴ Na yield is set as the photon sampling probability of photon source of each organ tissue, and the Na yield is set to have ²⁴ A human photon source model with Na content distribution;

based on the fact that ²⁴ A human body photon source model with distributed Na content obtains photon fluence at a set distance from the abdomen of the human body digital model in different irradiation geometric modes by utilizing a particle transport simulation program;

calculating neutron fluence corresponding to the neutron dose limit value of the human body, and according to the neutron fluence corresponding to the neutron dose limit value of the human body and the neutron of unit fluence under the condition of external irradiation of single-energy neutrons, determining the neutron fluence of each organ tissue in the human body digital model ²⁴ Obtained by Na yield from each organ corresponding to neutron dose limit in human body ²⁴ Activity of Na;

according to photon fluence at a set distance from the abdomen of the digital phantom under different irradiation geometries and the neutron dose limit value generated by each organ corresponding to the neutron dose limit value ²⁴ And Na activity, namely obtaining the peripheral dose equivalent rate at the set distance from the human digital model abdomen at the neutron irradiation end moment.

2. The high-throughput neutron dose evaluation method of claim 1,

a method for establishing a digital model of a human body using a preset tomographic image data set of the human body and obtaining the number of pixels per organ tissue, comprising,

starting from the 1 st pixel of the first image of the human body tomography image data set, traversing and acquiring the color value of each pixel of all human body tomography images;

color values C corresponding to respective organ tissues _n (a, b, c) obtaining the total number of pixels of each organ tissue; wherein a, B and c respectively represent integer component values of red R, green G and blue B in an RGB color space, and a is more than or equal to 0 and less than or equal to 255,0 and less than or equal to B and less than or equal to 255,0 and less than or equal to c and less than or equal to 255; the organ tissue includes skin, bone, brain, heart, lung, liver, kidney, spleen, stomach, large intestine, small intestine, and muscle;

accumulating all the pixel numbers of each organ tissue to obtain the pixel number P of each organ tissue _n 。

3. The high-throughput neutron dose evaluation method of claim 1,

according to the tissue of each organ ²³ Obtaining the mass percentage of Na, the mass of the organ tissues and the Avgalois constant of each organ tissue in the human digital model ²³ The number of Na atoms is realized by the following formula:

S _n =M _n ×Y _n (N _a ，p)/23×N _A

wherein S is _n Representing each organ tissue in a digital model of the human body ²³ Number of Na atoms, N _A Denotes the Avogastron constant, Y _n (N _a P) of organ tissue ²³ Na in percentage by mass; m is a group of _n Representing organ tissue mass; in addition, the air conditioner is provided with a fan,

the organ tissue mass is obtained by the following formula: m _n = R◊P _n ◊ρ _n N is the number of organ tissues (1,2,3 … T), T is the resolution of the human digital model, and P is the number of organ tissues _n Number of pixels of organ tissue, p _n Is the density of each organ tissue.

4. The high-throughput neutron dose evaluation method of claim 1,

according to the neutron fluence sum of each organ tissue in the human body digital model ²³ The number of Na atoms is obtained, and the number of each organ tissue in the human body digital model under the condition of external irradiation of unit-fluence single-energy neutrons is obtained ²⁴ The Na yield is realized by the following formula,

P _n （G，E）/Φ（G，E）= Φ _n （G，E，ε）×σ（ε）×S _n ×A

wherein, P _n (G, E)/phi (G, E) represents the tissue of each organ in the digital human body model under the condition of external irradiation of unit fluence monoenergetic neutrons ²⁴ Na yield; p _n (G, E) represents the generation of monoenergetic neutrons with energy E in various organ tissues under different irradiation geometries ²⁴ The number of Na atoms, phi (G, E) represents the fluence of a neutron source with the energy of E under different irradiation geometric modes; phi _n (G, E, ε) represents the neutron fluence of each organ tissue in the human digital model; σ (ε) represents the energy of a neutron with ε ²³ Cross section where Na capture reaction occurs; s _n Representing each organ tissue in a digital model of the human body ²³ The number of Na atoms; a represents the cross-sectional area of the neutron source; in addition, the air conditioner is provided with a fan,

neutron fluence phi of each organ tissue in the digital phantom _n (G, E, ε) is obtained by the following formula:

Φ _n （G，E，ε）= L _n /( R×P _n )

g represents the out-of-neutron irradiation geometry, G ∈ (LLAT, RLAT, AP, PA, ISO), wherein LLAT represents left lateral irradiation, RLAT represents right lateral irradiation, AP represents forward irradiation, PA represents backward irradiation, and ISO represents isotropic irradiation; e represents the initial monoenergetic neutron energy incident to the human body, and epsilon represents the neutron energy of the initial monoenergetic neutron energy entering the organ tissue n after the moderation of other organ tissues; l is a radical of an alcohol _n Representing the length of a neutron's motion track in organ tissue, R representing the digital model of the bodyResolution of type P _n The number of pixels of the organ tissue.

5. The high-throughput neutron dose evaluation method of claim 1,

a method of providing individual organ tissues as a photon source, comprising,

starting from the 1 st pixel of the first image of the human body tomography image data set, traversing and acquiring the color value of each pixel of all human body tomography images;

screening pixels with color values corresponding to certain organ tissues, setting the types of emitted particles corresponding to the pixels as photons, and setting the probability of the emitted particles corresponding to the pixels as the probability of certain organ tissues in a human digital model under the condition of unit fluence single energy neutron external irradiation ²⁴ Na yield P _n （G，E）/Φ（G，E）；

Traversing all pixels of all images of the human body tomographic image data set to complete the photon source setting of each organ tissue; wherein the photon energy in each organ tissue photon source is set to be 1.369MeV and 2.754MeV.

6. The high-throughput neutron dose evaluation method of claim 1,

the distance from the human digital model abdomen is set to be d between the radiation patrol instrument and the abdomen of a person to be detected when the radiation patrol instrument is perpendicular to the abdomen surface for detection, and d is not less than 5 cm and not more than 30 cm.

7. The high-throughput neutron dose evaluation method of claim 1,

the peripheral dose equivalent rate at a set distance from the abdomen of the digital phantom at the interval time is obtained by the following formula,

wherein,H ^* (G, E) represents the peripheral dose equivalent rate at a set distance from the abdomen of the digital human body model corresponding to the interval time, H ´ (G, E) represents the peripheral dose equivalent rate at a set distance from the abdomen of the digital human body model at the end time of neutron irradiation, E is a constant, and T is a constant ²⁴ Half-life of Na; in addition, the air conditioner is provided with a fan,

the peripheral dose equivalent rate H ´ (G, E) at a set distance from the abdomen of the digital phantom at the end of neutron irradiation is obtained by the following equation,

Φ _d (G, L) represents the photon fluence at a set distance from the abdomen of the digital phantom of the human body in different irradiation geometric modes,

indicating production of neutron dose limits in humans for respective organs ²⁴ The activity of the Na is high,

representing for all organs ²⁴ Human body obtained after Na activity accumulation ²⁴ Total activity of Na; f (G, E) represents the conversion coefficient of unit fluence of monoenergetic photons to the surrounding dose equivalent.

8. A high-flux neutron dose evaluation device, characterized in that the device comprises,

the radiation patrol instrument measuring module is used for measuring the peripheral dose equivalent rate of a person to be detected at a set distance from the abdomen of the human body by using the radiation patrol instrument;

the judgment threshold value obtaining module is used for obtaining the peripheral dose equivalent rate at the set distance from the human digital model abdomen corresponding to the interval time according to the interval time from the neutron irradiation ending time of the person to be detected to the radiation inspection instrument measuring time and the pre-obtained peripheral dose equivalent rate at the set distance from the neutron irradiation ending time to the human digital model abdomen; the method for acquiring the peripheral dose equivalent rate at the set distance from the neutron irradiation ending time to the human digital model abdomen comprises the following steps,

establishing a human body digital model by using a preset human body tomography image data set, and acquiring the pixel number of each organ tissue;

assigning corresponding element compositions and density values to the organ tissues of the human digital model, and determining the mass of each organ tissue according to the density values;

obtaining tissue of each organ ²³ Percentage by mass of Na, further according to the tissue of each organ ²³ Obtaining the mass percentage of Na, the mass of the organ tissues and the Avgalois constant of each organ tissue in the human digital model ²³ The number of Na atoms;

obtaining the neutron fluence of the monoenergetic neutrons in each organ tissue in the human digital model under different irradiation geometric modes with the energy of E by utilizing a particle transport simulation program, and obtaining the neutron fluence sum of each organ tissue in the human digital model according to the neutron fluence sum of each organ tissue in the human digital model ²³ The number of Na atoms is obtained, and the number of each organ tissue in the human body digital model under the condition of external irradiation of unit-fluence single-energy neutrons is obtained ²⁴ Na yield;

setting each organ tissue as photon source by using particle transport simulation program, and arranging the monoenergetic neutrons with energy of E and different irradiation geometries in each organ tissue in the human digital model ²⁴ Na yield is set as photon sampling probability of photon source of each organ tissue, and Na yield is set to be ²⁴ A human photon source model with Na content distribution;

the judgment module is used for judging whether the neutron dose of the person to be detected is larger than the neutron dose limit value or not according to the peripheral dose equivalent rate at the set distance from the human body digital model abdomen corresponding to the interval time and the actually measured peripheral dose equivalent rate at the set distance from the human body abdomen; wherein,

and when the actually measured peripheral dose equivalent rate at the set distance from the human abdomen is greater than the peripheral dose equivalent rate at the set distance from the human digital model abdomen corresponding to the interval time, judging that the neutron dose of the person to be detected is greater than the neutron dose limit value.

9. An electronic device, characterized in that the electronic device comprises:

at least one processor; and (c) a second step of,

a memory communicatively coupled to the at least one processor; wherein,

the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the steps in the high-throughput neutron dose evaluation method of any of claims 1 to 7.

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