Neutron source emissivity valuing device and neutron source emissivity measuring method

Abstract

The embodiment of the invention provides a neutron source emissivity valuing device and a neutron source emissivity measuring method. The neutron source emissivity valuing device comprises a solution pool, a measuring chamber, a circulating pipeline, a shielding body and a detector. The solution tank is provided with a first accommodating cavity for accommodating an activating solution and a second accommodating cavity for accommodating a neutron radioactive source; the measuring chamber is provided with a third accommodating cavity and a measuring cavity; the shielding body is provided with a fourth accommodating cavity for accommodating the measuring chamber and a communication channel communicated with the outside, and the communication channel is communicated with the measuring cavity; the detector is arranged in the communication channel, and one end of the detector extends into the measuring cavity. According to the neutron source emissivity valuing device, the detector in the measurement chamber can be taken out through the communication channel, so that on one hand, the detector is simpler and more convenient to disassemble and assemble; on the other hand, the detector can be independently packaged and stored, and collision damage of the detector is effectively prevented.

Description

Technical Field

[0001] This application relates to the technical field of neutron metrology, and in particular to a device for determining the emissivity of a neutron source and a method for measuring the emissivity of a neutron source. Background Technology

[0002] A neutron source is a device used to generate neutrons and has wide applications in scientific research, medicine, industry, and agriculture. Neutron emissivity refers to the number of neutrons emitted by a neutron source per unit time and is a core parameter for measuring the intensity of a neutron source.

[0003] In related technologies, neutron source emissivity determination devices are based on activation analysis and can be used to determine the emissivity of neutron sources for radioactive nuclides. However, during the measurement process, the detector of these devices is encased in a shielded chamber as a fixed component, making it impossible to remove directly. The disassembly and assembly process is complex and inconvenient for storage and transportation. Summary of the Invention

[0004] In view of this, the main objective of the embodiments of this application is to provide a neutron source emissivity determination device and a neutron source emissivity measurement method that facilitates the assembly and disassembly of the detector.

[0005] To achieve the above objectives, the technical solution of this application embodiment is implemented as follows: The first aspect of this application provides a device for setting the emission rate of a neutron source, comprising: The solution pool has a first containment cavity and a second containment cavity, the first containment cavity being used to contain an activation liquid and the second containment cavity being used to contain a neutron radiation source; the first containment cavity and the second containment cavity are separated. The measuring chamber has a third receiving cavity and a measuring cavity, the third receiving cavity being separated from the measuring cavity; A circulation pipeline connects the first receiving cavity and the third receiving cavity. A shielding body having a fourth receiving cavity and a communication channel communicating with the outside, wherein the measuring chamber is disposed in the fourth receiving cavity and the communication channel is connected to the measuring cavity; A detector is disposed in the communication channel, and one end of the detector extends into the measurement cavity through the communication channel.

[0006] In one embodiment, the outer wall of the solution pool has a detector mounting position, and the detector can be selectively disposed in one of the measuring cavity and the detector mounting position.

[0007] In one embodiment, the neutron source emissivity setting device includes a movable support, and the solution pool, the measurement chamber, and the shield are disposed on the movable support.

[0008] In one embodiment, the neutron source emission rate setting device further includes a mechanical pump, which is disposed on the circulation pipeline and located on the movable support.

[0009] In one embodiment, in a projection plane parallel to the horizontal plane, at least a portion of the projection of the solution pool coincides with the projection of the measuring chamber; and / or, The solution pool is located on the top side of the measuring chamber.

[0010] In one embodiment, the shielding body includes an inner shielding body and an outer shielding body. The inner shielding body has the fourth accommodating cavity, and the outer shielding body wraps around the outside of the inner shielding body. One of the inner shielding body and the outer shielding body is a photon shielding body, and the other is a neutron shielding body. The connecting channel includes a first sub-channel and a second sub-channel that are interconnected. The inner shielding body has the first sub-channel, and the outer shielding body has the second sub-channel.

[0011] In one embodiment, one end of the second receiving cavity extends through the solution pool to form an opening, the second receiving cavity is arranged in a vertical direction, and the opening faces vertically upward.

[0012] In one embodiment, the activating solution is a manganese sulfate solution or a vanadium sulfate solution.

[0013] In one embodiment, the detector is a gamma detector.

[0014] A second aspect of this application provides a method for measuring the emissivity of a neutron source, the method comprising: The neutron radiation source is placed in the second containment cavity, and the activation liquid in the second containment cavity is irradiated by the neutron radiation source. Control the flow of the activation solution along the circulation pipeline; The detector is placed in the communicating channel to measure the radiation emitted by the decay of the activated liquid in the third containment cavity.

[0015] In one embodiment, the solution pool further has a detector mounting position, and after the detector is placed in the communicating channel, the neutron source emissivity measurement method further includes: Remove the neutron radiation source from the second receiving cavity; The detector is positioned at the detector mounting location to measure the radiation emitted by the decay of the activated liquid within the first containment cavity.

[0016] This application provides a neutron source emissivity determination device and a neutron source emissivity measurement method. The neutron source emissivity determination device includes a solution pool, a measurement chamber, a detector, a circulation pipeline, and a shield. The solution pool has a first and a second receiving cavity. The first receiving cavity is used to contain an activation liquid, and the second receiving cavity is used to contain a neutron radiation source. The first and second receiving cavities are separated. The measurement chamber has a third receiving cavity and a measurement cavity, which are separated. The first and third receiving cavities are connected by the circulation pipeline. The shield has a fourth receiving cavity and a connecting channel to the outside. The measurement chamber is located in the fourth receiving cavity, and the connecting channel is connected to the measurement cavity. The detector is located in the connecting channel, and one end of the detector extends into the measurement cavity through the connecting channel. Thus, the connecting channel of the shield connects the measurement cavity to the outside, and the detector in the measurement chamber can be removed and installed through the connecting channel. This makes the detector easier to disassemble and assemble, and allows the detector to be individually packaged and stored, effectively preventing damage from collisions. For example, during the calibration and setting of the emissivity of a neutron radiation source, the detector is placed in the measurement cavity. After the calibration is completed, the detector can be removed from the measurement cavity through the connecting channel to prevent the detector from being hit. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a neutron source emissivity setting device according to an embodiment of this application; Figure 2 for Figure 1 Schematic diagram of the intermediate solution tank; Figure 3 for Figure 1 Schematic diagram of the structure of the measurement chamber and shielding enclosure; Figure 4 A schematic diagram of the first process of a neutron source emissivity measurement method provided in an embodiment of this application; Figure 5 This is a schematic diagram of the second process of a neutron source emissivity measurement method provided in an embodiment of this application.

[0018] Explanation of reference numerals in the attached figures 10. Solution pool; 10a. First containment cavity; 10b. Second containment cavity; 11. Detector mounting position; 20. Measurement chamber; 20a. Third containment cavity; 20b. Measurement cavity; 30. Detector; 40. Shielding body; 40a. Connecting channel; 41. Inner shielding body; 42. Outer shielding body; 50. Circulation pipeline; 51. First valve; 52. Second valve; 60. Mechanical pump; 70. Movable support; 80. Activation solution; 90. Neutron radiation source. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] In the description of the embodiments of this application, the technical terms "first", "second", "third", "fourth", etc. are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0021] In this application, the terms "upper" and "lower" or their positional relationships are based on the appendix. Figure 1 The orientation or positional relationship shown is for illustrative purposes only and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0022] Unless otherwise defined, all technical and scientific terms used in the embodiments of this application have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the embodiments of this application is for the purpose of describing the embodiments of this application only and is not intended to limit this application.

[0023] One embodiment of this application provides a device for setting the emittance of a neutron source. Please refer to [link to relevant documentation]. Figures 1 to 3 The neutron source emissivity setting device includes a solution pool 10, a measurement chamber 20, a detector 30, a circulation pipeline 50, and a shield 40.

[0024] The solution pool 10 has a first receiving cavity 10a and a second receiving cavity 10b. The first receiving cavity 10a is used to receive the activation liquid 80, and the second receiving cavity 10b is used to receive the neutron radiation source 90. The first receiving cavity 10a and the second receiving cavity 10b are separated.

[0025] The measuring chamber 20 has a third receiving cavity 20a and a measuring cavity 20b, which are separated from each other; the first receiving cavity 10a and the third receiving cavity 20a are connected by a circulation pipe 50.

[0026] The shield 40 has a fourth receiving cavity and a communication channel 40a that communicates with the outside. The measuring chamber 20 is disposed in the fourth receiving cavity, and the communication channel 40a communicates with the measuring chamber 20b.

[0027] The detector 30 is disposed in the communication channel 40a, and one end of the detector 30 extends into the measurement cavity 20b through the communication channel 40a.

[0028] Specifically, the first cavity 10a of the solution pool 10 is used to contain the activation liquid 80, the second cavity 10b of the solution pool 10 is used to contain the neutron radiation source 90, and a detector 30 is installed in the measuring chamber 20. Thus, the neutron radiation source 90 can irradiate the activation liquid 80, which is activated after irradiation. The activated liquid 80 decays and emits radiation. The detector 30 can convert the optical signal or charge difference generated by the interaction between the radiation and the material of the detector 30 into an electrical pulse signal. By analyzing the intensity of the electrical pulse signal, the emissivity of the neutron radiation source 90 can be calculated.

[0029] The first receiving cavity 10a and the second receiving cavity 10b of the solution pool 10 are separated, which prevents the activation liquid 80 from directly contacting the neutron radiation source 90. This effectively prevents a reaction from occurring on the surface of the neutron radiation source 90 during contact with the activation liquid 80, which could lead to corrosion of the neutron radiation source 90's casing by the activation liquid 80 and complete damage to the neutron radiation source 90.

[0030] The specific arrangement of the second receiving cavity 10b is not limited.

[0031] For example, a portion of the top of the solution pool 10 is recessed to the center, thereby enabling the neutron radiation source 90 to be located at the geometric center of the solution pool 10. As a result, the emitted neutrons can be more fully slowed down by the activation liquid 80 and captured to generate radionuclides.

[0032] The third receiving cavity 20a of the measuring chamber 20 is separated from the measuring cavity 20b, which prevents the activation liquid 80 in the third receiving cavity 20a from directly contacting the detector 30. This effectively prevents the activation liquid 80 from adhering to the surface of the detector 30 and corroding or damaging the detector 30.

[0033] The specific arrangement between the third receiving cavity 20a and the measuring cavity 20b is not limited.

[0034] Exemplarily, a portion of the outer surface of the measuring chamber 20 is recessed to form a measuring cavity 20b. A third receiving cavity 20a is formed inside the measuring chamber 20, and the third receiving cavity 20a extends circumferentially around the measuring cavity 20b. The detection end of the detector 30 extends into the measuring chamber 20 and is located at the center of the third receiving cavity 20a. This allows the detector 30 to receive a greater intensity of the X-ray signal.

[0035] The circulation pipeline 50 refers to the pipeline through which the activating liquid 80 flows between different chambers. Thus, the activating liquid 80 in the first receiving chamber 10a can enter the third receiving chamber 20a, and the activating liquid 80 in the third receiving chamber 20a can re-enter the first receiving chamber 10a.

[0036] The shield 40 has a fourth receiving cavity, and the measurement chamber 20 is disposed in the fourth receiving cavity of the shield 40. That is to say, the shield 40 surrounds the outside of the measurement chamber 20, which can effectively reduce the influence of the external environment on the measurement results of the detector 30 in the measurement chamber 20.

[0037] The specific structural form of the shield 40 is not limited.

[0038] For example, the shield 40 includes a photon shield 40 and a neutron shield 40. On the one hand, it effectively prevents damage to the detector 30 from neutrons leaking from the boundary of the solution pool 10; on the other hand, it effectively reduces the background count generated on the detector 30 by naturally occurring radioactive nuclides in the environment, making the emissivity determination result of the neutron radiation source 90 more accurate.

[0039] The specific arrangement of the measuring chamber 20 and the fourth accommodating chamber is not limited.

[0040] For example, measuring chamber 20 fills the fourth receiving cavity.

[0041] For example, the measuring chamber 20 is located behind the fourth receiving cavity, and a portion of the fourth receiving cavity is not filled by the measuring chamber 20.

[0042] One end of the detector 30 extends into the measurement cavity 20b through the connecting channel 40a. It should be noted that the specific arrangement of the detector 30 and the measurement cavity 20b is not limited. For example, the signal receiving end of the detector 30 extends into the measurement cavity 20b to receive X-ray signals.

[0043] It should be noted that the detector 30 can be installed through the communication channel 40a, so that one end extends into the measurement cavity 20b. The detector 30 can be detachably mounted in the communication channel 40a.

[0044] In the neutron source emissivity calibration device of this application embodiment, the shield 40 is connected to the measurement cavity 20b via a connecting channel 40a. The detector 30 is disposed in the connecting channel 40a, and one end of the detector 30 extends into the measurement cavity 20b through the connecting channel 40a. Thus, the connecting channel 40a of the shield 40 connects the measurement cavity 20b to the outside world. The detector 30 inside the measurement chamber 20 can be removed and installed through the connecting channel 40a, which simplifies the disassembly and assembly of the detector 30. Furthermore, the detector 30 can be individually packaged and stored, effectively preventing damage from collisions. For example, during the emissivity calibration of the neutron radiation source 90, the detector 30 is disposed in the measurement cavity 20b. After calibration, the detector 30 can be removed from the measurement cavity 20b through the connecting channel 40a, preventing the detector 30 from being damaged by collisions.

[0045] In one embodiment, please refer to Figure 2The outer wall of the solution pool 10 has a detector mounting position 11, and the detector 30 can be selectively located in either the measuring cavity 20b or the detector mounting position 11.

[0046] Specifically, the manner in which the detector mounting position 11 is located on the outer wall of the solution pool 10 is not limited. For example, the detector mounting position 11 may be formed by a recess in a portion of the outer wall of the solution pool 10. Alternatively, the detector mounting position 11 may be formed by a protrusion in a portion of the outer wall of the solution pool 10.

[0047] For example, the detector 30 is installed with its orientation pointing towards the geometric center of the solution pool 10. As a result, the detector 30 can receive a greater intensity of the X-ray signal.

[0048] It should be noted that the detector 30 can be selectively set in either the measurement cavity 20b or the detector mounting position 11. This means that both the measurement cavity 20b and the detector mounting position 11 can be used to install the detector 30, and the operator can selectively install the detector 30 in either the measurement cavity 20b or the detector mounting position 11 according to the needs of the experiment.

[0049] For example, detector 30 may be placed inside measurement cavity 20b as needed. This effectively reduces the background count generated by naturally occurring radionuclides in the environment on detector 30, resulting in a more accurate emissivity determination of neutron source 90.

[0050] For example, detector 30 is placed on detector mounting position 11. The amount of activation liquid 80 in solution pool 10 is greater than that in measurement chamber 20. Detector 30 can measure the radiation emitted by the decay of activation liquid 80 throughout the entire first containment cavity 10a, and the radiation signal received by detector 30 is stronger. Therefore, detector 30 can better distinguish the signal generated by the low-emissivity neutron source 90 from the background signal. The emissivity of the neutron source 90 can be calculated based on the measured radiation signal intensity, thereby calibrating the low-emissivity neutron source 90.

[0051] It should be noted that the neutron source emission rate setting device may consist of only one detector 30, which can be selectively installed at any location by the operator according to experimental requirements.

[0052] Of course, in some embodiments, the neutron source emission rate setting device may also include two detectors 30, with one detector 30 provided on both the measurement cavity 20b and the detector mounting position 11.

[0053] It should be noted that the specific connection method between the detector 30 and the measuring cavity 20b is not limited. For example, the detector 30 may simply extend into the measuring cavity 20b. Alternatively, the detector 30 and the measuring cavity 20b may be connected via other auxiliary connection methods, such as snap-fit ​​fixing, threaded connection, adhesive bonding, plug-in connection, or other connection methods.

[0054] Of course, the specific arrangement of the detector 30 at the detector mounting position 11 is not limited. For example, the detector 30 can be placed on the detector mounting position 11. Or, the detector 30 can be connected to the detector mounting position 11 through other auxiliary connection methods, such as snap-fit ​​fixing, threaded connection, adhesive bonding, plug-in connection, or other connection methods.

[0055] In related technologies, standard devices for neutron source emissivity determination often produce weak signals when measuring low-emissivity neutron sources, making it difficult to distinguish them well from the ambient background signal. The measurement limit is typically only 10⁻⁶. 5 s -1 The scale is insufficient to meet the current market demand of 10 4 s -1 The calibration requirements for neutron radiation sources with emission rates on the order of magnitude.

[0056] In the neutron source emissivity calibration device of this embodiment, by placing the detector 30 on the detector mounting position 11 on the outer wall of the solution pool 10, and since the amount of activated liquid 80 in the solution pool 10 is greater than the amount of activated liquid 80 in the measurement chamber 20, the detector 30 can measure the radiation emitted by the decay of the activated liquid 80 throughout the entire first containment cavity 10a. Therefore, the radiation signal received by the detector 30 is stronger, the measurement range is increased, and the emissivity of the neutron source 90 can be calculated based on the measured radiation signal intensity, thereby calibrating the neutron source 10a. 4 s -1 A low-emissivity neutron radiation source of magnitude 90.

[0057] In one embodiment, please refer to Figure 1 The neutron source emissivity setting device includes a movable support 70, a solution pool 10, a measuring chamber 20, and a shield 40, which are mounted on the movable support 70.

[0058] Specifically, the movement method of the movable support 70 is not limited. For example, several casters are provided at the bottom of the movable support 70, enabling the movable support 70 itself to move. Furthermore, the casters are omnidirectional casters. Thus, it is more convenient to move the neutron source emission rate setting device to the transport equipment via the movable support 70, and the position adjustment within the laboratory is also more flexible.

[0059] For example, the mobile support 70 is moved and transported by mechanical equipment.

[0060] It should be noted that the specific arrangement of the solution tank 10 and the movable support 70 is not limited. For example, the solution tank 10 and the movable support 70 may be welded and fixed. Alternatively, the solution tank 10 and the movable support 70 may be detachably connected by bolts. Yet another example is that the solution tank 10 may be placed on the movable support 70.

[0061] Of course, the specific arrangement of the measuring chamber 20, the shield 40, and the movable support 70 is not limited. For example, the measuring chamber 20 and the shield 40 may be welded and fixed to the movable support 70. Alternatively, the measuring chamber 20 and the shield 40 may be detachably connected to the movable support 70 by bolts. Yet another example is that the measuring chamber 20 and the shield 40 may be placed on the movable support 70.

[0062] In related technologies, the standard apparatus for neutron source emissivity determination is relatively large, thus it can only be used in a fixed laboratory. Furthermore, because neutron sources are radioactive, their transfer is strictly controlled, making it inconvenient to transport them to a laboratory for emissivity calibration. Therefore, neutron source emissivity determination is particularly difficult.

[0063] In the neutron source emissivity calibration device of this application embodiment, the solution pool 10, the measuring chamber 20, and the shield 40 are mounted on a movable support 70. The movable support 70 serves as a transport carrier for the solution pool 10, the measuring chamber 20, and the shield 40. The movable support 70, together with the solution pool 10, the measuring chamber 20, and the shield 40, constitutes a movable neutron source emissivity calibration device. Therefore, the neutron source emissivity calibration device is not subject to transportation restrictions, offering the advantage of convenient transportation. Calibrating the neutron radiation source 90 by transporting the neutron source emissivity calibration device avoids long-distance transportation of the neutron radiation source 90, thus solving the problem of inconvenient emissivity calibration of the neutron radiation source 90. For example, when the emissivity of a certain neutron radiation source 90 needs to be calibrated, the neutron source emissivity calibration device can be transported to the location of the neutron radiation source 90 requiring calibration, and the emissivity of the neutron radiation source 90 can be calibrated using the neutron source emissivity calibration device.

[0064] In one embodiment, please refer to Figure 1 The neutron source emission rate setting device also includes a mechanical pump 60, which is installed on the circulation pipeline 50 and located on the movable support 70.

[0065] Specifically, a mechanical pump 60 is installed on the circulation pipeline 50, which serves as the power source for the flow of the activation liquid 80. The mechanical pump 60 drives the activation liquid 80 to circulate. The activation liquid 80 in the first receiving chamber 10a enters the third receiving chamber 20a through the circulation pipeline 50. The radiation signal emitted by the decay of the activation liquid 80 is received by the detector 30. The activation liquid 80 in the third receiving chamber 20a re-enters the first receiving chamber 10a through the circulation pipeline 50 to be irradiated. The mechanical pump 60 circulates and stirs the activation liquid 80, which enables the radioactive nuclides produced by the neutron radiation source 90 irradiating the activation liquid 80 to be more evenly distributed in the activation liquid.

[0066] It should be noted that the specific location of the mechanical pump 60 is not limited. For example, the mechanical pump 60 may be installed on the pipeline from the solution tank 10 to the measuring chamber 20. Or, the mechanical pump 60 may be installed on the pipeline from the measuring chamber 20 to the solution tank 10.

[0067] Of course, the specific arrangement of the mechanical pump 60 and the movable support 70 is not limited. For example, the mechanical pump 60 may be welded to the movable support 70. Or, the mechanical pump 60 may be detachably connected to the movable support 70 by bolts. Or, the mechanical pump 60 may be placed on the movable support 70.

[0068] The specific model of mechanical pump 60 is not limited. For example, mechanical pump 60 can be a centrifugal pump, a gear pump, a peristaltic pump, or even a vacuum pump.

[0069] In one embodiment, a first valve 51 is provided between the solution tank 10 and the measuring chamber 20, and a second valve 52 is provided between the measuring chamber 20 and the mechanical pump 60.

[0070] The first valve 51 controls the connection between the solution pool 10 and the measuring chamber 20. The first valve 51 can connect or isolate the solution pool 10 and the measuring chamber 20. When the first valve 51 is open, the activation liquid 80 in the solution pool 10 can enter the measuring chamber 20, and the radiation signal emitted by the decay of the activation liquid 80 is received by the detector 30. When the first valve 51 is closed, the channel between the solution pool 10 and the measuring chamber 20 is cut off, and the activation liquid 80 in the solution pool 10 cannot enter the measuring chamber 20.

[0071] The first valve 51 controls the connection between the measuring chamber 20 and the mechanical pump 60. The first valve 51 can connect or disconnect the measuring chamber 20 from the mechanical pump 60. When the first valve 51 is open, the activating solution 80 in the measuring chamber 20 can enter the mechanical pump 60 and be driven by the mechanical pump 60 to circulate along the circulation pipeline 50. When the first valve 51 is closed, the passage between the measuring chamber 20 and the mechanical pump 60 is cut off, and the activating solution 80 cannot enter the mechanical pump 60.

[0072] It should be noted that the first valve 51 and the second valve 52 can be opened or closed individually or simultaneously. The first valve 51 can be installed on the circulation pipeline 50 connecting the solution pool 10 and the measuring chamber 20; the second valve 52 can be installed on the circulation pipeline 50 connecting the measuring chamber 20 and the mechanical pump 60. Therefore, by controlling the opening and closing of the first valve 51 and the second valve 52, the flow rate of the activation solution 80 can be adjusted, optimizing the measurement conditions and the operating status of the device. Furthermore, in the event of an anomaly in the neutron source emissivity setting device, closing the first valve 51 and the second valve 52 can quickly cut off the circulation pipeline 50, reducing the possibility of an accident.

[0073] In one embodiment, please refer to Figure 1 In a projection plane parallel to the horizontal plane, at least a portion of the projection of the solution pool 10 coincides with the projection of the measuring chamber 20.

[0074] Specifically, the overlapping area between the projection of solution pool 10 and the projection of measurement chamber 20 is not limited. It can be that the projections of solution pool 10 and measurement chamber 20 completely overlap. Alternatively, the projection of measurement chamber 20 may include the projection of solution pool 10. It can also be that the projection of solution pool 10 includes the projection of measurement chamber 20. Furthermore, the projection of measurement chamber 20 may partially overlap with the projection of solution pool 10. This allows the neutron source emission rate determination device to have a smaller footprint.

[0075] In one embodiment, the solution pool 10 is located on the top side of the measuring chamber 20.

[0076] In other words, the solution pool 10 is located above the measuring chamber 20. As a result, the activation solution 80 in the solution pool 10 can enter the measuring chamber 20 through the circulation pipe 50 under the action of gravity.

[0077] It should be noted that the measuring chamber 20 is surrounded by a shield 40, which has a relatively large mass. The measuring chamber 20 and the shield 40 are located below the solution pool 10. This lowers the center of gravity of the neutron source emissivity setting device, giving it greater anti-tipping stability.

[0078] In one embodiment, please refer to Figure 1 and Figure 3 The shield 40 includes an inner shield 41 and an outer shield 42. The inner shield 41 has a fourth receiving cavity, and the outer shield 42 is wrapped around the outside of the inner shield 41. One of the inner shield 41 and the outer shield 42 is a photon shield 40, and the other is a neutron shield 40. The connecting channel 40a includes a first sub-channel and a second sub-channel that are interconnected. The inner shield 41 has the first sub-channel, and the outer shield 42 has the second sub-channel.

[0079] Specifically, the inner shield 41 has a fourth receiving cavity to accommodate the measurement chamber 20, the measurement chamber 20 is disposed within the fourth receiving cavity, and the detector 30 is disposed within the measurement cavity 20b of the measurement chamber 20. Thus, the shield 40 surrounds the outside of the measurement chamber 20, effectively reducing the influence of external factors on the measurement results of the detector 30 in the measurement chamber 20.

[0080] The outer shield 42 is wrapped around the outside of the inner shield 41. It should be noted that the specific arrangement of the inner shield 41 and the outer shield 42 is not limited.

[0081] For example, the inner shield 41 and the outer shield 42 are tightly fitted together; For example, a portion of the inner shield 41 has a gap with the outer shield 42.

[0082] The inner shield 41 and the outer shield 42 are respectively a photon shield 40 and a neutron shield 40. Therefore, on the one hand, this effectively prevents damage to the detector 30 inside the measurement chamber 20 from neutrons leaking from the boundary of the solution pool 10; on the other hand, it effectively reduces the background count generated by naturally occurring radionuclides in the environment on the detector 30 inside the measurement chamber 20, making the emissivity determination of the neutron radiation source 90 more accurate.

[0083] It should be noted that the inner shield 41 can be a photon shield 40, and the outer shield 42 can be a neutron shield 40. Thus, the photon shield 40 with a higher density and a thinner thickness is placed in the inner layer of the shield 40 structure, while the neutron shield 40 with a lower density and a thicker thickness is placed in the outer layer of the shield 40 structure, in order to reduce manufacturing costs and the overall mass of the shield 40.

[0084] Alternatively, the inner shield 41 can be a neutron shield 40, and the outer shield 42 can be a photon shield 40.

[0085] The shielding body 40 has a connecting channel 40a, which includes a first sub-channel and a second sub-channel that are interconnected. The first sub-channel is connected to the measurement chamber 20b, and the second sub-channel is connected to the outside. As a result, the detector 30 inside the measurement chamber 20 can be taken out through the connecting channel 40a, which makes it easier to replace the detector 30. On the other hand, the detector 30 can be packaged and stored separately, effectively preventing the detector 30 from being damaged by collision.

[0086] In one embodiment, please refer to Figure 2 The second receiving cavity 10b has an opening at one end that extends through the solution pool 10. The second receiving cavity 10b is arranged vertically and the opening faces vertically upward.

[0087] Specifically, one end of the second receiving cavity 10b extends through the solution pool 10 to form an opening, which is connected to the second receiving cavity 10b. This allows the neutron radiation source 90 to be placed in the second receiving cavity 10b through the opening.

[0088] The second receiving cavity 10b is arranged vertically with its opening facing vertically upwards. Therefore, the neutron source 90 is located at the bottom of the second receiving cavity 10b, resulting in a more accurate placement of the neutron source 90 and thus smaller measurement errors.

[0089] The shape and structure of the second receiving cavity 10b are not limited. For example, the second receiving cavity 10b is a cylindrical cavity. Or, the second receiving cavity 10b is a frustum-shaped cavity.

[0090] In one embodiment, the activation solution 80 is a manganese sulfate solution or a vanadium sulfate solution.

[0091] Specifically, the activation solution 80 can be a manganese sulfate solution. Alternatively, the activation solution 80 can be a vanadium sulfate solution. Thus, some of the neutrons emitted by the neutron source 90 are slowed down by the nuclides in the solution and captured by some naturally occurring stable nuclides in the activation solution 80 (2516340-U-CP-MKWE), continuously generating radioactive nuclides. The radiation released during their decay is received by the detector 30.

[0092] In one embodiment, detector 30 is a gamma detector 30.

[0093] Specifically, the activating liquid 80 decays and emits gamma rays. The gamma detector 30 can convert the light signal or charge difference generated by the interaction between the gamma rays and the material of the detector 30 into an electrical pulse signal. By analyzing the intensity of the electrical pulse signal, the emissivity of the neutron radiation source 90 can be calculated.

[0094] One embodiment of this application provides a neutron source emissivity measurement method, which is used in the neutron source emissivity setting device of any of the embodiments of this application. Please refer to [link to relevant documentation]. Figure 4 ,include: S10. Place the neutron radiation source 90 into the second containment cavity 10b and irradiate the activation liquid 80 in the second containment cavity 10b through the neutron radiation source 90.

[0095] S20, control the flow of the activation solution 80 along the circulation pipeline 50.

[0096] S30. The detector 30 is placed in the connecting channel 40a to measure the radiation emitted by the decay of the activated liquid 80 in the third containment cavity 20a.

[0097] Specifically, in this embodiment, the detector 30 fixed on the detector mounting position 11 is removed, and then the neutron radiation source 90 is placed into the second receiving cavity 10b of the solution pool 10. This prevents neutrons emitted by the neutron radiation source 90 from leaking through the boundary of the solution pool 10, thereby avoiding damage to the detector 30 on the detector mounting position 11.

[0098] It should be noted that the second containment cavity 10b has an opening communicating with the outside, and a portion of the second containment cavity 10b is located at the geometric center of the solution pool 10. Thus, the neutron radiation source 90 is placed through the opening at the geometric center of the solution pool 10 to irradiate the activation liquid 80. The distances from the neutron radiation source 90 to the boundaries of the solution pool 10 in all directions are made as consistent as possible, allowing it to be more fully slowed down and captured by the nuclides in the activation liquid 80, generating radionuclides.

[0099] The neutron radiation source 90 continuously irradiates the activation liquid 80 in the second containment cavity 10b for an unlimited duration.

[0100] For example, the activation solution 80 is a manganese sulfate solution. The neutron radiation source 90 continuously irradiates the activation solution 80 in the second containment cavity 10b for more than or equal to 30 hours. The continuous generation reaction counteracts the decay reaction of the radionuclide, thereby making the generation and decay rate of the radionuclide in the solution pool 10 reach a balanced state. The activation solution 80 is close to the radioactive saturation state, and the radiation signal measured by the detector 30 is more stable and the measurement data is more accurate.

[0101] Mechanical pump 60 is turned on, circulating the activation solution 80. The activated solution 80 in the first receiving chamber 10a enters the third receiving chamber 20a through the circulation pipeline 50. Detector 30 in the measuring chamber 20 measures the radiation emitted by the decay of the activated solution in the third receiving chamber 20a. Thus, after circulation and stirring, the activation solution 80 achieves a uniform distribution of radionuclides, and the emissivity of the neutron source 90 can be calculated based on the measured radiation signal intensity.

[0102] In one specific embodiment, the solution pool 10 also has a detector mounting position 11, please refer to [reference needed]. Figure 5 After detector 30 is positioned in connecting channel 40a in step S30, the neutron source emissivity measurement method further includes: S40. Remove the neutron radiation source 90 from the second receiving cavity 10b.

[0103] S50. The detector 30 is set on the detector mounting position 11 to measure the radiation emitted by the decay of the activated liquid 80 in the first receiving cavity 10a through the detector 30.

[0104] Specifically, the neutron radiation source 90 is removed from the second receiving cavity 10b, and then the detector 30 is placed on the detector mounting position 11. This effectively prevents neutrons emitted by the neutron radiation source 90 from leaking through the boundary of the solution pool 10, thereby preventing neutron irradiation damage to the detector 30 on the detector mounting position 11.

[0105] The detector 30 is mounted on the detector mounting position 11 on the outer wall of the solution pool 10. The amount of activation liquid 80 in the solution pool 10 is greater than that in the measuring chamber 20. The detector 30 can measure the radiation emitted by the decay of the activation liquid 80 in the entire first receiving cavity 10a, and the radiation signal received by the detector 30 is stronger. Therefore, the detector 30 can better distinguish the 10 4 s -1 The measurement range of the low-emissivity neutron source 90 and the ambient background signal is increased. The emissivity of the neutron source 90 can be calculated from the measured radiation signal intensity, thus enabling calibration of 10... 4 s -1 A low-emissivity neutron radiation source of magnitude 90.

[0106] In the description of this application, the references to terms such as "in one embodiment," "in some embodiments," "in a specific embodiment," or "exemplary," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the embodiments of this application. In this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine the different embodiments or examples described in this application, as well as the features of the different embodiments or examples.

[0107] The above are merely preferred embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the protection scope of this application.

Claims

1. A neutron source emittance setting device, characterized in that, include: The solution pool has a first containment cavity and a second containment cavity, the first containment cavity being used to contain an activation liquid and the second containment cavity being used to contain a neutron radiation source; the first containment cavity and the second containment cavity are separated. The measuring chamber has a third receiving cavity and a measuring cavity, the third receiving cavity being separated from the measuring cavity; A circulation pipeline connects the first receiving cavity and the third receiving cavity. A shielding body having a fourth receiving cavity and a communication channel communicating with the outside, wherein the measuring chamber is disposed in the fourth receiving cavity and the communication channel is connected to the measuring cavity; A detector is disposed in the communication channel, and one end of the detector extends into the measurement cavity through the communication channel.

2. The neutron source emission rate setting device according to claim 1, characterized in that, The outer wall of the solution pool has a detector mounting position, and the detector can be selectively disposed in either the measuring cavity or the detector mounting position.

3. The neutron source emission rate setting device according to claim 1, characterized in that, The neutron source emissivity setting device includes a movable support, and the solution pool, the measurement chamber, and the shield are mounted on the movable support.

4. The neutron source emission rate setting device according to claim 3, characterized in that, The neutron source emission rate setting device also includes a mechanical pump, which is installed on the circulation pipeline and located on the movable support.

5. The neutron source emission rate setting device according to any one of claims 1-4, characterized in that, Within a projection plane parallel to the horizontal plane, at least a portion of the projection of the solution pool coincides with the projection of the measuring chamber; and / or, The solution pool is located on the top side of the measuring chamber.

6. The neutron source emission rate setting device according to any one of claims 1-4, characterized in that, The shielding body includes an inner shielding body and an outer shielding body. The inner shielding body has the fourth accommodating cavity. The outer shielding body wraps around the outside of the inner shielding body. One of the inner shielding body and the outer shielding body is a photon shielding body, and the other is a neutron shielding body. The connecting channel includes a first sub-channel and a second sub-channel that are interconnected. The inner shielding body has the first sub-channel, and the outer shielding body has the second sub-channel.

7. The neutron source emission rate setting device according to any one of claims 1-4, characterized in that, The second receiving cavity has an opening at one end that extends through the solution pool. The second receiving cavity is arranged vertically, and the opening faces vertically upward.

8. The neutron source emission rate setting device according to any one of claims 1-4, characterized in that, The activation solution is a manganese sulfate solution or a vanadium sulfate solution; and / or, The detector is a gamma detector.

9. A method for measuring the emissivity of a neutron source, characterized in that, The neutron source emissivity setting device according to any one of claims 1-8; the neutron source emissivity measurement method includes: The neutron radiation source is placed in the second containment cavity, and the activation liquid in the second containment cavity is irradiated by the neutron radiation source. Control the flow of the activation solution along the circulation pipeline; The detector is placed in the communicating channel to measure the radiation emitted by the decay of the activated liquid in the third containment cavity.

10. The neutron source emissivity measurement method according to claim 9, characterized in that, The solution pool also has a detector mounting position, and after the detector is placed in the communicating channel, the neutron source emissivity measurement method further includes: Remove the neutron radiation source from the second receiving cavity; The detector is positioned at the detector mounting location to measure the radiation emitted by the decay of the activated liquid within the first containment cavity.

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