A neutron radiation shielding structure, a shielding device made therefrom, and a detection method

Abstract

The present invention provides a neutron radiation shielding structure, a shielding device made therefrom, and a detection method. The neutron radiation shielding structure includes: a matrix and a cantilever. The cantilever stands on the matrix and is arranged in an array. Thereby, the number of albedo neutrons is reduced, and thus the neutron shielding effect is effectively improved.

Description

Technical Field

[0001] The present invention relates to neutron radiation shielding technology, and in particular to a neutron radiation shielding structure, a shielding device made therefrom, and a detection method. Background Art

[0002] With the rapid development of industries such as nuclear energy, radiation processing, non-destructive testing, and radiation medicine, high-energy rays have been widely present in multiple fields such as industry, medicine, and scientific research. Common high-energy rays include X-rays, γ-rays, and neutron rays, etc. Therefore, the radiation and protection problems of such high-energy rays have always been the focus of people's attention.

[0003] Among them, neutrons have strong penetration when passing through matter, and pose a more serious danger to the human body than the same dose of X-rays and γ-rays. After the human body is irradiated by neutrons, the gastrointestinal tract and male gonads will be severely damaged, the biological effect of inducing tumors is high, and it is easy to cause early death. At the same time, the damaged body is prone to infection and the degree is serious. The relative biological effect of causing cataract of the eye lens is 2 to 14 times that of γ or X-rays. It is extremely easy to cause hematopoietic organ failure, digestive system damage, and central nervous system damage. It can also cause malignant tumors, leukemia, cataracts, etc. Neutron radiation can also produce genetic effects and affect the development of the offspring of the irradiated person.

[0004] Therefore, in actual work, for the safety of staff, the shielding protection of neutrons will be particularly important.

[0005] Currently, existing neutron shielding technologies usually focus on the research of shielding materials. For example, traditional neutron shielding materials mainly use boron-based or lead-based polyethylene composite shielding materials as the main body, and the concrete shielding surface of the neutron shielding device made of such shielding materials is mostly in the structure of plates or sheets.

[0006] Therefore, the inventor considered taking a different approach and tried to improve the structure of the shielding surface made of existing shielding materials to further supplement and enhance the neutron shielding effect. Summary of the Invention

[0007] The main purpose of the present invention is to provide a neutron radiation shielding structure, a shielding device made therefrom, and a detection method to achieve the inventor's goal in the background art.

[0008] To achieve the above object, according to the first aspect of the present invention, a neutron radiation shielding structure is provided, which includes: a matrix, overhangs. The matrix is a plane, and the overhangs are columnar and stand on the matrix. Among them, the overhangs are in the shape of a cuboid and are arranged at intervals perpendicular to the matrix, or in the shape of a cube and are arranged at intervals perpendicular to the matrix, or are arranged in a cross-shaped array to form a waffle-like layout, where each side surface of the overhang is perpendicular to the matrix and the top surface is parallel to the matrix.

[0009] Further, in a possible preferred embodiment, the array pitch of the cantilevers on the substrate is less than or equal to 5 cm.

[0010] Further, in a possible preferred embodiment, at least one of the substrate and the cantilever is made of concrete including Portland cement.

[0011] To achieve the above object, according to the second aspect of the present invention, there is also provided a neutron radiation shielding detection method, the steps of which include: establishing a spherical detection system, arranging a detector at the hemispherical position in the positive direction of the X-axis of the system, placing any one of the above neutron shielding structures at the origin of the system, and making the center of the substrate coincide with the origin of the system coordinates, and the connection surface between the substrate and the cantilever coincide with the YOZ plane of the system; the neutron source is arranged on the X-axis to be incident on the origin position of the system for the detector to read the detection data.

[0012] To achieve the above object, according to the third aspect of the present invention, there is also provided a neutron radiation shielding device, which includes: a shielding surface, wherein the shielding surface is made of any one of the above neutron radiation shielding structures.

[0013] Through the neutron radiation shielding structure provided by the present invention, the shielding device and the detection method made thereof, compared with the shielding surface structure of the prior art, can significantly reduce the number of albedo neutrons, thereby effectively improving the neutron shielding effect, and the implementation cost is low, which is suitable for improving the prior art, conducive to the popularization of technology, and in actual use, for the maintenance workers, they can stay in the radiation operation area for a longer time, which will be of effective help to the entire operation plan. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0015] Figure 1 It is a schematic structural diagram of the neutron radiation shielding structure according to the first embodiment of the present invention;

[0016] Figure 2 It is the spatial distribution of albedo neutrons in Table 1 according to the first embodiment of the present invention;

[0017] Figure 3 It is the energy distribution diagram of albedo neutrons in Table 2 according to the first embodiment of the present invention;

[0018] Figure 4 It is a schematic diagram of the array layout of regular hexagonal cantilevers on the substrate according to the first embodiment of the present invention;

[0019] Figure 5Schematic diagram of the cross-shaped overhang arranged on the substrate in the second embodiment of the present invention;

[0020] Figure 6 Schematic diagram of the cross-shaped overhang in the second embodiment of the present invention being arrayed into a waffle structure on the substrate;

[0021] Figure 7 Table 3 spatial distribution data graph in the second embodiment of the present invention;

[0022] Figure 8 Table 4 energy distribution data graph in the second embodiment of the present invention;

[0023] Figure 9 Isotropic neutron source detection waffle structure data graph in the second embodiment of the present invention;

[0024] Figure 10 Neutron shielding detection system diagram in the third embodiment of the present invention;

[0025] Figure 11 Neutron shielding detection system diagram in the third embodiment of the present invention. Detailed implementation manners

[0026] The following will describe in detail the detailed implementation manners of the present invention. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made. These all belong to the protection scope of the present invention. In addition, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0027] In order to enable those skilled in the art to better understand the solution of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. (1)

[0029] Please refer to Figures 1 to 4 As shown, the neutron radiation shielding structure provided by the present invention includes: a substrate, an overhang, and the overhang stands on the substrate and is arranged in an array. Among them, as Figure 1 shown, the overhang can be selected as a hexahedron rectangle. In other alternative implementation manners, a regular hexahedron shape can also be adopted.

[0030] Among them, the base body can be a planar shielding wall solution in the prior art, and this overhang can be arranged on the planar shielding wall of the prior art according to the solution of this embodiment to form a transformation of the prior art, and it can still achieve better performance in reducing the number of backscattered neutrons than the solution of setting only the existing planar shielding wall alone.

[0031] In addition, there is no unique limitation on the preparation material used for this overhang in this embodiment. In the experimental example of this embodiment, it is preferably made of Portland cement concrete. However, those skilled in the art should understand that in other possible alternative implementation manners, other materials with enhanced neutron shielding performance can also be used for substitution. Therefore, any solution that improves this overhang only by material substitution is within the scope of disclosure of this embodiment.

[0032] Experimental Example 1

[0033] To prove the effectiveness of the neutron radiation shielding structure proposed in this embodiment, this embodiment conducted experiments based on the following parameters.

[0034] Base body: A planar shielding wall is used, with dimensions of 100x100x35 cm

[0035] Overhang: A regular hexahedron is used, with dimensions of 5x5x10 cm

[0036] [[ID=G19]]Angle of the regular hexahedron: Arranged perpendicular to the wall surface

[0037] Arrangement density: 10x10 cm

[0038] Spacing distance: 5 cm up and down

[0039] Preparation material: Both the base body and the overhang are made of Portland cement concrete

[0040] Comparison object: Planar shielding wall

[0041] The experimental data and analysis of the regular hexahedron structure are as follows:

[0042]

[0043]

[0044] Table 1 Spatial distribution data (100 eV) Table 2 Energy distribution data (100 eV)

[0045] According to the above experimental results, it can be seen that:

[0046] 1) The number of backscattered neutrons generated by the shielding wall with the overhang structure is significantly reduced:

[0047] As Figure 4As shown, an array structure of cantilevers overhanging on a matrix in a regular hexahedron structure is presented. From the output data in Table 1 or Table 2, it can be seen that the total number of albedo neutrons decreases from 64.73% to

[0048] 55.94%, with an overall decrease of 8.79%.

[0049] 2) Among them, the number of neutrons in the middle and high latitude regions (30° - 90°) decreases significantly, while the number of neutrons in the low latitude region

[0050] (0° - 30°) increases slightly:

[0051] Based on the data in Table 1, the spatial distribution of albedo neutrons can be plotted Figure 2 . It can be clearly seen from the figure that the number of neutrons in the middle and high latitude regions (30° - 90°) decreases significantly, while the number of neutrons in the low latitude region (0°

[0052] - 30°) increases slightly.

[0053] 3) The number of neutrons in the high - energy region decreases significantly, while the number of neutrons in the low - energy region increases slightly:

[0054] Based on the data in Table 2, the energy distribution of albedo neutrons can be plotted Figure 3 . It can be clearly seen from the figure that the number of neutrons in the high - energy region decreases significantly, while the number of neutrons in the low - energy region increases slightly.

[0055] According to the above experimental result data, it can be known that through the neutron radiation shielding structure provided in this embodiment, the number of albedo neutrons can be significantly reduced. Therefore, compared with a planar shielding wall, its neutron shielding effect is better. (II)

[0057] Please refer to Figures 5 to 8 As shown, in another preferred embodiment, the neutron radiation shielding structure provided by the present invention includes: a matrix and a cantilever. The cantilever stands on the matrix and is arranged in an array. Among them, as Figure 5 shown, the cantilever can be selected as a cross - shaped body, and each cross - shaped cantilever can be arranged at intervals and perpendicular to the matrix.

[0058] However, it is worth mentioning that if the cross - shaped cantilever is arranged in an array form with the head and tail connected as Figure 6 shown to form a waffle - like shape, it is better than the scheme in Example 1 and this embodiment where each cross - shaped cantilever is arranged at intervals.

[0059] Specifically, Figure 4 is the cross - section of the regular hexahedron structure at the x = 5 plane, Figure 6 is the cross - section of the waffle structure at the x = 5 plane. Among them, the example structures in this embodiment and Experimental Example 2 change from a Figure 4 regular hexahedron toFigure 6 The structure of the "waffle" is formed by extending the material along two directions of the y-axis and the z-axis until it is connected to the adjacent overhanging structure. Therefore, in the following Experimental Example 2, taking this Figure 4 regular hexahedron structure and Figure 6 the waffle structure as an example for data test and comparison.

[0060] In addition, it is worth mentioning that the design concept of this waffle structure is that after the inventor accidentally discovered through experiments the trend that "the volume of the overhanging structure is directly proportional to the albedo neutron suppression force", the volume of the overhanging structure was increased as much as possible on the basis of the regular hexahedron, and the derivative product was obtained.

[0061] On the other hand, in this embodiment, the matrix can be the plane shielding wall solution of the prior art, and the overhanging can be arranged on the plane shielding wall of the prior art according to the solution of this embodiment to form a transformation of the prior art, and it can still achieve better performance than the solution of setting the existing plane shielding wall alone in terms of reducing the number of albedo neutrons.

[0062] At the same time, there is no unique limitation on the preparation material used for the overhanging in this embodiment. In the experimental examples of this embodiment, it is preferably made of Portland cement concrete. However, those skilled in the art should understand that in other possible alternative embodiments, other materials with enhanced neutron shielding performance can also be used for substitution. Therefore, any solution that improves the overhanging only by material substitution is within the scope of disclosure of this embodiment.

[0063] Experimental Example 2

[0064] To prove the effectiveness of the neutron radiation shielding structure proposed in this embodiment, this embodiment conducted experiments according to the following parameters.

[0065] Among them, in this embodiment, the structure of the waffle is evolved from the regular hexahedron structure and can be composed of several small crosses with a thickness of 5 cm and a height of 10 cm placed in the middle of a single 10x10 cm small grid. The experimental material is still Portland cement concrete.

[0066] The experimental data and analysis of the waffle structure are as follows:

[0067]

[0068]

[0069] Table 3 Spatial Distribution Data Table (1eV)

[0070]

[0071]

[0072] Table 4 Quantity Distribution Data Table (1eV)

[0073] Using the spatial distribution data table in Table 3 (1eV), Figure 7 , the energy distribution data table in Table 4 (1eV), and Figure 8 As shown, taking the neutron source as an example, the albedo neutrons generated by the planar shielding wall, the regular hexahedron, and the waffle structure are 63.48%, 54.04%, and 31.08% respectively. In the case of 1eV neutrons incident on the shielding body, compared with the shielding wall without the overhanging structure, the overhanging structure of the regular hexahedron reduces the albedo neutrons by 9.44%, and the waffle-shaped overhanging structure reduces the albedo neutrons by 32.4%.

[0074] It can be seen from the above experimental results that the waffle structure in Example 2 has a significant improvement in the key parameters of reducing the number of albedo neutrons compared with the regular hexahedron structure in Example 1, and its neutron shielding effect is better.

[0075] In addition, in order to prove that the waffle structure can be applied to more complex usage scenarios (such as isotropic neutron sources), and whether the waffle structure is still effective, the inventor has also made corresponding verifications.

[0076] For example, when irradiating the convex part and the concave part surfaces of the waffle structure with two neutron beams respectively, and then comparing with the ordinary plane, as Figure 9 shown, the first curve A1, the second curve A2, and the third curve A3 are the conditions of incident on the concave part, the convex part, and the ordinary plane of the waffle structure respectively. The area formed by the curve and the x-axis in this figure represents the number of albedo neutrons generated. The area of the A2 curve is 5.95% larger than the blue curve, and the area of the A1 curve is 32.4% smaller than the A3 curve. It can be seen that the total attenuation caused by incident on the concave part is much larger than the gain caused by incident on the convex part.

[0077] And the isotropic neutron source can be decomposed and simplified into the situation of several single-beam neutron sources. It can be seen that under more complex neutron source conditions, the waffle structure can still achieve an ideal effect of reducing the number of albedo neutrons.

[0078] In addition, it should be noted that according to the above-mentioned Example 1 and Example 2, the scheme of adding an overhang on the planar shielding wall can effectively reduce the number of albedo neutrons and improve the neutron shielding effect. However, although the overhang structure is exemplified by the hexahedron and cross shapes in this embodiment, the shape of the overhang is not limited. Those skilled in the art can completely deploy an overhang with other shaped structures on the substrate according to the concept of the present invention to meet the requirements of different neutron shielding effects. Therefore, any implementation method of replacing the overhang shape is within the disclosure scope of the present invention.

[0079] On the other hand, according to the above embodiments of the present invention, it can be seen that for the array structure cantilevered on the substrate, it is not necessary for the cantilevers to be completely spaced apart from each other. Therefore, the above description of the array layout in the present invention includes the meaning that the cantilevers can be completely spaced apart (such as a hexahedron structure) or at least partially connected (a waffle structure).

[0080] On the other hand, although the substrate is exemplified by a plane in the above embodiments, in other possible alternative embodiments, it can also be a curved surface structure to meet the structural requirements of the shielding scenario. Therefore, no matter what kind of changed structure the substrate adopts, as long as it can enable the cantilevers to be arrayed thereon and protrude from the surface of the substrate, it falls within the disclosure scope of the present invention. (Three)

[0082] In the third aspect of the present invention, a method for detecting neutron radiation shielding is further provided. The steps include: establishing a spherical detection system, arranging detectors at the hemispherical position in the positive direction of the X-axis of the system, placing the neutron shielding structure in the above embodiments at the origin of the system, and making the center of the substrate coincide with the origin of the system coordinates, and the connection surface between the substrate and the cantilever coincide with the YOZ plane of the system; the neutron source is arranged on the X-axis (such as (40, 0, 0)) to be incident on the origin position of the system (such as (0, 0, 0)) for the detector to read the detection data.

[0083] The neutron source used for detection preferably includes: low-energy neutrons of 1 eV and 100 eV, which are incident on the origin position in the form of a beam of neutrons.

[0084] Specifically, according to the experimental results of the above Embodiment 1 and Embodiment 2, as long as the cantilever scheme of the present invention is introduced, it will have three levels of influence on the albedo neutrons generated in the system:

[0085] 1) Influence on the total count of albedo neutrons. The number of albedo neutrons generated by the shielding wall is reduced.

[0086] 2) Influence on the spatial distribution of albedo neutrons. The number of neutrons in the middle and high latitude regions (30° - 90°) is significantly reduced, and the number of neutrons in the low latitude region (0° - 30°) slightly increases.

[0087] 3) Influence on the energy distribution of albedo neutrons. The number of neutrons in the high energy region is significantly reduced, and the number of neutrons in the low energy region slightly increases.

[0088] To help understand the second effect, as Figure 10As shown in the figure, the neutron shielding detection system is exemplified. The entire detection system is a sphere. The hemisphere in the positive X-axis direction is set as the detector. The hexahedron is a schematic position of the shielding wall. The center of the shielding wall surface coincides with the center of the coordinate axis. The cantilever structure is also directly added to this surface, and this surface also coincides with the YOZ plane. The neutron source is located on the X-axis at (40, 0, 0). The initial energies of the simulated neutron sources are 1 eV and 100 eV, and they are incident on the origin position (0, 0, 0) in the form of a beam of neutrons.

[0089] As Figure 11 shown, No. 1 is the position of the shielding body; No. 2 is the position where the incident neutron source is located; the spherical surface in the positive x-axis direction is the detector. The neutron sources used in the simulation are mainly low-energy neutrons (1 eV and 100 eV), and the neutron source in the simulation experiment is located at the position of the coordinate axis (40, 0, 0). Thus, the detection of neutron radiation shielding can be effectively realized. (IV)

[0091] In the fourth aspect of the present invention, a neutron radiation shielding device is further provided, which includes: a shielding surface, wherein the shielding surface is made of the neutron radiation shielding structure in any of the above embodiments.

[0092] In summary, through the neutron radiation shielding structure provided by the present invention, the shielding device made thereof, and the detection method, compared with the shielding surface structure of the prior art, the number of albedo neutrons can be significantly reduced, thereby effectively improving the neutron shielding effect. Moreover, the implementation cost is low, which is suitable for improving the prior art and conducive to the popularization of technology. And in actual use, for the maintenance workers, they can stay in the radiation operation area for a longer time, which will be of effective help to the entire operation plan.

[0093] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments to better explain the principle and practical application of the present invention, so that those skilled in the relevant technical field can understand and utilize the present invention well. The present invention is only limited by the claims and their full scope and equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0094] Those skilled in the art can understand that, in addition to implementing the systems, devices, and their respective modules provided by the present invention in the form of pure computer-readable program codes, the method steps can be logically programmed to enable the systems, devices, and their respective modules provided by the present invention to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. Therefore, the systems, devices, and their respective modules provided by the present invention can be regarded as a kind of hardware components, and the modules included therein for implementing various programs can also be regarded as the structures within the hardware components; the modules for implementing various functions can also be regarded as either software programs for implementing the methods or the structures within the hardware components.

[0095] In addition, all or part of the steps in the methods of the above embodiments can be completed by a program instructing relevant hardware. The program is stored in a storage medium, including several instructions for enabling a single-chip microcomputer, a chip, or a processor to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs.

[0096] In addition, any combination can be made among the various different implementation manners of the embodiments of the present invention, as long as it does not violate the idea of the embodiments of the present invention, and it should also be regarded as the content disclosed by the embodiments of the present invention.

Claims

1. A neutron radiation shielding structure, characterized in that, Comprising: A base body and a cantilever. The base body is planar, and the cantilever is columnar and stands upright on the base body. The cantilever is in the shape of a cuboid and is arranged at intervals perpendicular to the base body array, or in the shape of a cube and is arranged at intervals perpendicular to the base body array, or is arranged in a waffle shape by being connected in a cross-shaped array. Each side surface of the cantilever is perpendicular to the base body, and the top surface is parallel to the base body.

2. The neutron radiation shielding structure according to claim 1, characterized in that, The array pitch of the cantilevers on the base body is less than or equal to 5 cm.

3. The neutron radiation shielding structure according to claim 1, characterized in that, At least one of the base body and the cantilever is made of concrete including Portland cement.

4. A neutron radiation shielding device, comprising: A shielding surface, characterized in that the shielding surface is made of the neutron radiation shielding structure according to any one of claims 1 to 3.

5. A method for detecting neutron radiation shielding, characterized in that the steps Comprising: Establish a spherical detection system. A detector is set at the hemispherical position in the positive direction of the X-axis of the system. The neutron radiation shielding structure according to any one of claims 1 to 3 is placed at the origin of the system, and the center of the base body coincides with the origin of the system coordinates, and the connection surface between the base body and the cantilever coincides with the YOZ plane of the system; the neutron source is set on the X-axis and is incident on the origin position of the system for the detector to read the detection data.

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