Coincidence activity measuring device

Abstract

The embodiment of the invention provides a coincidence activity measuring device. The coincidence activity measuring device comprises a light-emitting chamber, a light detection assembly and a gamma ray detector. The light-emitting chamber comprises a light-transmitting cavity with a containing cavity and working gas filled in the containing cavity, the containing cavity is used for installing an alpha radioactive source, and the working gas can emit fluorescent light under radiation of the alpha radioactive source. The light detection assembly is arranged on one side outside the light-emitting cavity and faces the alpha radioactive source so as to be used for detecting fluorescence emitted by the working gas. The gamma ray detector is arranged outside the light-emitting cavity and used for detecting gamma rays emitted by the alpha radioactive source. The coincidence activity measuring device provided by the embodiment of the invention is convenient to measure.

Description

Technical Field

[0001] The present application relates to the technical field of particle detection, and in particular to a coincidence activity measurement device. Background Art

[0002] In the related technology, the α-γ coincidence device is a low-background α nuclide activity measurement device with strong anti-interference ability. It can measure the activity of mixed nuclide α samples and solve the problem of serious spectrum overlap of traditional α spectrometer and Compton plateau annihilation of low-energy γ rays of γ spectrometer.

[0003] However, due to the limitation of the short range of α particles (less than 5 cm in the air), the α-γ coincidence spectrometer measurement in related technologies is troublesome. It has strict requirements on the measurement source, measurement equipment, measurement distance, etc., and there are problems such as sample damage, high process and small space of measurement equipment, long measurement process, and inability to directly and quickly measure complex nuclide samples.

[0004] For example, the α-γ coincidence device composed of ZnS-HPGe and PIPS-HPGe requires an electroplating device to prepare an electroplated thin source for measurement. The source preparation is time-consuming and has a high risk of radioactive contamination. The detector window is very thin, usually in the micron level, and the equipment manufacturing process is high. The distance between the source and the detector is very small (5mm-4cm), the measurement space is limited, and the PIPS detector also needs to be evacuated. As for liquid scintillator detectors, although luminescence detection is used, the sample needs to be destroyed and dissolved in scintillation fluid, resulting in untreatable toxic scintillation fluid and radioactive mixed waste. These conditions limit the convenient and long-distance measurement of α nuclide samples of any matrix and specification for direct sampling. It can be seen that the measurement device in the related art is troublesome for measuring α particles. Summary of the invention

[0005] In view of this, the main purpose of the embodiments of the present application is to provide a coincidence activity measurement device that is convenient for measurement.

[0006] To achieve the above purpose, the technical solution of the embodiment of the present application is implemented as follows:

[0007] The present application provides a device for measuring activity, including:

[0008] A light-emitting chamber, the light-emitting chamber comprising a light-transmitting cavity having a receiving cavity, and a working gas filled in the receiving cavity, the receiving cavity being used to install an α radiation source, and the working gas being able to emit fluorescence under the radiation of the α radiation source;

[0009] A light detection component, which is arranged outside the light-emitting chamber and faces the α-radiation source to detect the fluorescence emitted by the working gas;

[0010] A gamma ray detector is arranged outside the light emitting chamber to detect the gamma rays emitted by the alpha radiation source.

[0011] In one embodiment, the light detection assembly is disposed on one side of the light-transmitting cavity along the circumferential direction, and the gamma-ray detector is disposed on the bottom side of the light-transmitting cavity.

[0012] In one embodiment, the gamma-ray detector is bonded to the bottom of the light-transmitting cavity, and at the bonding point between the light-transmitting cavity and the gamma-ray detector, at least a portion of the bottom of the light-transmitting cavity is a carbon fiber window.

[0013] In one embodiment, the central axis of the end surface of the gamma-ray detector close to one side of the light-transmitting cavity coincides with the central axis of the light-transmitting cavity, and the alpha radiation source is located on the central axis of the light-transmitting cavity.

[0014] In one embodiment, the accommodating cavity has an installation position for installing an α radiation source, and the distance between the installation position and the inner wall of the light-transmitting cavity is greater than or equal to the range of α particles of the α radiation source.

[0015] In one embodiment, the coincidence activity measurement device further comprises an integrated digital spectrometer, and the integrated digital spectrometer is respectively connected to the light detection assembly and the gamma-ray detector signal.

[0016] In one embodiment, the light detection assembly includes a photomultiplier tube and an optical filter, wherein the optical filter is disposed between the photomultiplier tube and the light emitting chamber, and the center of the photomultiplier tube, the center of the optical filter and the center of the light emitting chamber are coaxially disposed.

[0017] In one embodiment, the compliance activity measuring device also includes a light reflecting component, which is arranged outside the light emitting chamber, and at least a portion of the light reflecting component is located on the side of the light emitting chamber away from the light detection component, so that part of the fluorescence emitted by the working gas is reflected toward one side of the light detection component.

[0018] In one embodiment, the light-transmitting cavity further has an airflow inlet and an airflow outlet;

[0019] The airflow inlet and the airflow outlet are respectively located on the inner wall of the light-transmitting cavity on two opposite sides of the α-radiation source; and / or,

[0020] The air flow outlet is located at the top side of the air flow inlet.

[0021] In one embodiment, at least a portion of the light-transmitting cavity is made of ultraviolet fused quartz glass; and / or,

[0022] The light-emitting chamber further comprises an ultraviolet anti-reflection film, and at least one of the inner surface and the outer surface of the periphery of the light-transmitting cavity is provided with the ultraviolet anti-reflection film.

[0023] The embodiment of the present application provides a compliance activity measurement device, which comprises a light-emitting chamber, a light detection assembly and a gamma-ray detector. The light-emitting chamber comprises a light-transmitting cavity having a receiving cavity, and a working gas filled in the receiving cavity, the receiving cavity is used to install an α radiation source, and the working gas can emit fluorescence under the radiation of the α radiation source. The light detection assembly is arranged outside the light-emitting chamber and faces the α radiation source to detect the fluorescence emitted by the working gas. Thus, on the one hand, the α particles of the α radiation source cause the working gas to radiate light, and then the fluorescence emitted by the working gas is detected by the light detection assembly, so that the detection of α particles can be conveniently realized, and the convenience of measurement can be improved. In addition, since the working gas and the α radiation source are both located in the receiving cavity, the purity of the working gas in the light-transmitting cavity can be greatly improved, the effect of saving the working gas can be achieved, and a stable measurement state can be entered quickly. At the same time, since the light detection assembly is arranged outside the light-emitting chamber, the risk of damage to the light detection assembly can be reduced in the process of filling the receiving cavity with working gas, and the safety performance of the compliance activity measurement device can be improved. On the other hand, the gamma ray detector is arranged outside the light-emitting chamber to detect the gamma rays emitted by the alpha radiation source, thereby enabling better measurement of gamma rays, facilitating single gamma spectrum measurement and alpha fluorescence-gamma coincidence spectrum measurement, and further facilitating alpha nuclide identification and activity measurement of the alpha radiation source. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a partial structural schematic diagram of an activity measurement device according to an embodiment of the present application;

[0025] Figure 2 A schematic diagram of the coordination relationship between a light emitting chamber, a light detection component and a light reflection component according to another embodiment of the present application;

[0026] Figure 3 This is a schematic diagram of the matching relationship between the radiation source mounting bracket and the α radiation source according to another embodiment of the present application, in which a cover is shown;

[0027] Figure 4 This is a schematic diagram of the coordination relationship among an alpha fluorescence detector, a gamma ray detector, an integrated digital spectrometer and a gamma spectrum analysis software according to yet another embodiment of the present application.

[0028] Description of Reference Numerals

[0029] 1. α fluorescence detector; 10. Light-emitting chamber; 11. Transparent cavity; 11a. Accommodating cavity; 11b. Air flow inlet; 11c. Air flow outlet; 111. Cavity body; 112. Cover; 12. Radiation source mounting bracket; 121. Frame; 122. Tray; 20. Light detection assembly; 21. Photomultiplier tube; 22. Light filter; 30. Light reflection assembly; 31. Reflection cavity; 40. Darkroom; 50. α radiation source; 60. γ-ray detector; 70. Integrated digital spectrometer; 80. γ spectrum analysis software; 90. Shielding room. DETAILED DESCRIPTION

[0030] In this application, the "first direction" orientation or position relationship is based on the attached Figure 2 It should be understood that these directional terms are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application.

[0031] The optical method of detecting alpha particles based on alpha radiation causing the working gas (such as nitrogen, argon and other gases) to emit light, that is, the working gas is excited by alpha particles, and the working gas is de-excited to generate fluorescence, and the radiation and luminescence caused by the working gas caused by alpha particles can be detected remotely through the light detection component 20. The method of detecting luminescence breaks the stringent requirements of the range on the alpha particle measurement source, detection distance, detector thin window, etc. For example, the fluorescence detection method can directly measure sampling samples of any shape and specification. The alpha radiation source 50 does not need to be made into a plating thin source using vacuum plating equipment, and can be a directly sampled wipe sample, a thin layer solution, nuclear material particles, air filter membrane, etc. It saves the equipment, manpower and time costs of preparing traditional plating sources, and does not increase additional environmental pollution. Fluorescence can be measured remotely, breaking the measurement space limitation, and the detection distance can be greater than 1 meter. It realizes the convenience of simple measurement equipment, convenient operation, and direct and fast measurement of samples, providing a basis for the on-site application of the equipment. There is no need to use semiconductor or scintillation detectors with thin windows. It only needs to use the light detection component 20 to detect the fluorescence emitted by the working gas, reducing the use of high-tech detectors. The measurement equipment is simple and the measurement is convenient.

[0032] An embodiment of the present application provides a device for measuring the activity of a component. Figure 1 and Figure 2 The compliance activity measuring device includes a light emitting chamber 10 , a light detection assembly 20 and a γ-ray detector 60 .

[0033] Specifically, at least a portion of the light-transmitting cavity 11 is made of light-transmitting material, which allows the fluorescence generated by the working gas to pass through, thereby facilitating measurement by the light detection component 20 .

[0034] According to actual conditions, the light-transmitting cavity 11 may be partially made of light-transmitting material. For example, the light-transmitting cavity 11 includes a cavity body 111 and a cover 112. A take-in and take-out port is formed on the top of the cavity body 111. The cover 112 is detachably covered on the take-in and take-out port. The light detection assembly 20 is arranged on the side of the cavity body 111. The cavity body 111 is made of light-transmitting material, and the cover 112 is made of polyethylene. Thus, on the one hand, by dividing the light-transmitting cavity 11 into the cavity body 111 and the cover 112, it is convenient to take and put the α radiation source 50 through the take-in and take-out port. On the other hand, the cavity body 111 is made of light-transmitting material, which can facilitate the fluorescence emitted by the working gas to be better emitted from the light-transmitting cavity 11, and thus facilitate the measurement of the light detection assembly 20. At the same time, the cover 112 is made of polyethylene, which can reduce the loss of the fluorescence emitted by the working gas from the top of the light-transmitting cavity 11, and there is a problem that it is difficult to be measured by the light detection assembly 20 arranged on the side of the light-transmitting cavity 11.

[0035] Of course, according to actual conditions, the entire area of ​​the light-transmitting cavity 11 may be made of light-transmitting material.

[0036] The specific material type of the light-transmitting cavity 11 is not limited.

[0037] Exemplarily, at least a portion of the light-transmitting cavity 11 is made of ultraviolet fused quartz glass, thereby facilitating the passage of fluorescence and improving the accuracy of measurement by the light detection assembly 20 .

[0038] Of course, in order to increase the light transmission effect, anti-reflection materials can also be provided.

[0039] For example, the light-emitting chamber 10 further includes an ultraviolet anti-reflection film, and at least one of the inner surface and the outer surface of the light-transmitting cavity 11 is provided with the ultraviolet anti-reflection film. It is understandable that only the inner surface of the light-transmitting cavity 11 is provided with the ultraviolet anti-reflection film, only the outer surface of the light-transmitting cavity 11 is provided with the ultraviolet anti-reflection film, or both the inner and outer surfaces of the light-transmitting cavity 11 are provided with the ultraviolet anti-reflection film. In this way, the light transmission effect can be improved.

[0040] The α radiation source 50 is placed in the accommodating chamber 11a, and the accommodating chamber 11a contains a working gas that can generate fluorescence under the radiation of the α radiation source 50. It should be noted that the specific type of the working gas can be determined according to actual needs, for example, the working gas includes nitrogen or argon.

[0041] The light detection component 20 is disposed outside the light emitting chamber 10 , and is a component capable of detecting the fluorescence emitted by the working gas.

[0042] In fact, the working gas can generate ultraviolet fluorescence under the irradiation of the α radiation source 50 , and the light-transmitting cavity 11 can allow the ultraviolet fluorescence to pass through so as to be measured by the light detection component 20 .

[0043] The specific structure of the light detection component 20 is not limited.

[0044] For example, the light detection assembly 20 includes a photomultiplier tube 21 and an optical filter 22, and the optical filter 22 is disposed between the photomultiplier tube 21 and the light emitting chamber 10. The photomultiplier tube 21 faces the α radiation source 50 to measure the fluorescence generated by the working gas under the irradiation of the α radiation source 50. The optical filter 22 can reduce the detection of interfering light, such as the optical filter 22 includes an optical filter.

[0045] It should be noted that the light emitting chamber 10 and the light detection assembly 20 need to be tested in a dark room 40 to reduce the influence of ambient light. The dark room 40 may be a part of the structure of the compliance activity measurement device, that is, the dark room 40 is a part of the compliance activity measurement device. Of course, the dark room 40 may also be a structure matching the compliance activity measurement device, that is, the dark room 40 is not a part of the compliance activity measurement device.

[0046] The gamma ray detector 60 can be used to measure the gamma rays emitted by the alpha nuclide of the alpha radiation source 50. Thus, the alpha fluorescence signal can be measured by the light detection assembly 20, and the gamma signal can be measured by the gamma ray detector 60, so that a single gamma energy spectrum can be obtained, thereby facilitating the alpha fluorescence-gamma coincidence energy spectrum, and further facilitating the alpha nuclide identification and activity measurement of the alpha radiation source 50.

[0047] The type of the γ-ray detector 60 is not limited, for example, the γ-ray detector 60 is a HPGe γ detector.

[0048] It should be noted that since the fluorescence yield of gamma rays, beta rays, etc. in the working gas is relatively small, for example, beta rays are 1 / 2600 of alpha rays, the alpha fluorescence detection method of measuring fluorescence through the light detection component 20 can ignore the interference of beta and gamma rays and has a better measurement effect.

[0049] The luminescent activity measuring device of the embodiment of the present application includes a light-emitting chamber 10, a light detection assembly 20 and a gamma-ray detector 60. The light-emitting chamber 10 includes a light-transmitting cavity 11 having a housing 11a, and a working gas filled in the housing 11a, wherein the housing 11a is used to install an α radiation source 50, and the working gas can emit fluorescence under the radiation of the α radiation source 50. The light detection assembly 20 is arranged outside the light-emitting chamber 10 and faces the α radiation source 50, so as to detect the fluorescence emitted by the working gas. Thus, on the one hand, the α particles of the α radiation source 50 cause the working gas to radiate light, and then the fluorescence emitted by the working gas is detected by the light detection assembly 20, so that the detection of α particles can be conveniently realized, and the convenience of measurement can be improved. Moreover, since the working gas and the α radiation source 50 are both located in the housing 11a, the purity of the working gas in the light-transmitting cavity 11 can be greatly improved, which can save the working gas and quickly enter a stable measurement state. At the same time, since the light detection assembly 20 is arranged outside the light emitting chamber 10, the risk of damage to the light detection assembly 20 can be reduced during the process of filling the working gas into the accommodating chamber 11a, and the safety performance of the coincidence activity measurement device can be improved. On the other hand, the gamma ray detector 60 is arranged outside the light emitting chamber 10 to detect the gamma rays emitted by the alpha radiation source 50. Thus, the measurement of gamma rays can be better achieved, and the single gamma spectrum measurement and alpha fluorescence-gamma coincidence spectrum measurement can be facilitated, and the alpha nuclide identification and activity measurement of the alpha radiation source 50 can be facilitated.

[0050] In the related art, the α radiation source and the photomultiplier tube are placed in the same darkroom, and the working gas is filled in by gas flow. However, since the light-sensitive area of ​​the photomultiplier tube is very small, only about 8mm, in order to collect fluorescence efficiently, a large-diameter lens is placed between the photomultiplier tube and the α radiation source to collect fluorescence, and the photomultiplier tube detects fluorescence near the focal length. Since the focal length is large due to the large lens diameter, the darkroom space is relatively large (greater than 20L), which makes it difficult to achieve a high-purity working gas in the darkroom, thereby affecting the fluorescence luminescence efficiency and wasting a lot of working gas.

[0051] In the related art, there is also a method of separating the α radiation source and the photomultiplier tube with a gate valve, evacuating the α radiation source side and then filling it with working gas, and then opening the gate valve to detect with the photomultiplier tube to avoid pressure damage to the photomultiplier tube. Although this method saves gas, the side where the photomultiplier tube is placed is a normal pressure environment containing air. When the gate valve is opened, air will mix into the vacuum side, reducing the purity of the working gas and affecting the gas fluorescence luminescence efficiency.

[0052] The α radiation source 50 and the working gas of the activity measurement device of the present application are both placed in the light-transmitting cavity 11, and the light detection assembly 20 is located outside the light-emitting chamber 10. Therefore, there is no problem that the darkroom 40 is relatively large due to the large diameter lens, thereby affecting the fluorescence luminescence efficiency. At the same time, since the light-transmitting cavity 11 separates the working gas and the light detection assembly 20, there is no problem of damage to the photomultiplier tube 21 due to vacuuming, and there is no problem of reduced purity of the working gas due to air mixing.

[0053] In one embodiment, please refer to Figure 1 and Figure 2 The light detection assembly 20 is arranged on one side of the light-transmitting cavity 11 along the circumferential direction, and the gamma-ray detector 60 is arranged on the bottom side of the light-transmitting cavity 11 .

[0054] It should be noted that the structural layout of the light detection assembly 20 and the gamma-ray detector 60 is the core of the coincidence activity measurement device, which is related to the efficiency of α and gamma rays, and further affects the coincidence efficiency index of the coincidence activity measurement device.

[0055] Since the light detection assembly 20 and the gamma-ray detector 60 measure different rays of the α radiation source 50, the light detection assembly 20 and the gamma-ray detector 60 are arranged on different sides of the light-transmitting cavity 11, which can facilitate the light detection assembly 20 and the gamma-ray detector 60 to measure the α radiation source 50 from different directions.

[0056] For example, the gamma-ray detector 60 is attached to the bottom of the light-transmitting cavity 11 , and at least a portion of the bottom of the light-transmitting cavity 11 is a carbon fiber window at the attachment point between the light-transmitting cavity 11 and the gamma-ray detector 60 .

[0057] Specifically, by arranging a carbon fiber window at the bottom of the light-transmitting cavity 11, the absorption of low-energy gamma rays of the alpha nuclide by the bottom wall of the light-transmitting cavity 11 can be reduced, so that the low-energy gamma rays emitted by the alpha nuclide can efficiently pass through the bottom wall of the light-transmitting cavity 11, thereby improving the detection efficiency of the gamma-ray detector 60 for gamma rays.

[0058] The gamma-ray detector 60 is in contact with the bottom of the light-transmitting cavity 11 , and the bottom of the light-transmitting cavity 11 may be partially or entirely made of carbon fiber windows.

[0059] For another example, the sidewalls of the light-transmitting cavity 11 along the circumferential direction are made of a light-transmitting material, thereby facilitating the passage of fluorescence, so as to facilitate measurement by the light detection component 20 .

[0060] In one embodiment, please refer to Figure 1, the central axis of the end face of the gamma-ray detector 60 close to the light-transmitting cavity 11 coincides with the central axis of the light-transmitting cavity 11, and the alpha radiation source 50 is located on the central axis of the light-transmitting cavity 11. In other words, the center line of the gamma-ray detector 60 and the center line of the light-transmitting cavity 11 are located on the same axis. Thus, the detection efficiency of the gamma-ray detector 60 for the gamma-rays of the alpha radiation source 50 can be further improved.

[0061] In one embodiment, the accommodating cavity 11 a has an installation position for installing the α radiation source 50 , and the distance between the installation position and the inner wall of the light-transmitting cavity 11 is greater than or equal to the range of α particles of the α radiation source 50 .

[0062] Specifically, considering the range of the α particles of the α radiation source 50, in order to make the energy of the α particles lost in the working gas as completely as possible and generate fluorescence, by controlling the distance between the installation position of the α radiation source 50 and the inner wall of the light-transmitting cavity 11 to be greater than or equal to the range of the α particles of the α radiation source 50, the distance from the α particles to the upper, lower, left and right walls of the chamber can be made as large as possible, thereby making the measurement of the α radiation source 50 more accurate.

[0063] For example, the α radiation source 50 is installed at the center of the accommodating chamber 11 a .

[0064] It should be noted that the specific size of the light-transmitting cavity 11 needs to meet the range of the α particles, and at the same time, its size should not be too large.

[0065] For example, the light-transmitting cavity 11 is a hollow cylindrical cavity with a diameter of 100 mm to 110 mm, a height of 100 mm to 110 mm, and a wall thickness of 1 mm. For example, the diameter of the light-transmitting cavity 11 is 100 mm, and the height is 100 mm.

[0066] In one embodiment, please refer to Figure 3 The light-emitting chamber 10 further includes a radiation source mounting bracket 12, which includes a frame 121 and a tray 122. The tray 122 is disposed on the frame 121 and is located at the center of the accommodating chamber 11a. The tray 122 is used to mount the α radiation source 50. Thus, the measurement of the α radiation source 50 can be made more accurate.

[0067] In one embodiment, please refer to Figure 4 The compliance activity measurement device also includes an integrated digital spectrometer 70, which is signal-connected to the light detection assembly 20 and the gamma-ray detector 60 respectively.

[0068] Specifically, the α fluorescence signal is detected by the light detection component 20, and the logic signal outputted by the light detection component 20 is inputted into the gate signal input terminal of the integrated digital spectrometer 70. The digital spectrometer also receives the signal of the γ-ray detector 60 to perform single γ energy spectrum measurement and coincident γ energy spectrum measurement, thereby obtaining the α fluorescence-γ coincidence energy spectrum, thereby realizing the α nuclide identification and activity measurement of complex samples.

[0069] In a specific embodiment, please refer to Figure 4 After the digital spectrometer receives the signal from the light detection component 20 and the signal from the gamma-ray detector 60, it starts measuring through the gamma spectrum analysis software 80 to obtain the α fluorescence-γ coincidence spectrum, and then the activity of the α radiation source 50 in the sample can be obtained by the corresponding analysis method.

[0070] In one embodiment, please refer to Figure 1 and Figure 2 The light detection assembly 20 includes a photomultiplier tube 21 and an optical filter 22, wherein the optical filter 22 is disposed between the photomultiplier tube 21 and the light emitting chamber 10, and the center of the photomultiplier tube 21, the center of the optical filter 22, and the center of the light emitting chamber 10 are coaxially disposed. Thus, by placing the centers of the three on the same axis, the measurement effect of the photomultiplier tube 21 can be improved.

[0071] In one embodiment, please refer to Figure 1 and Figure 2 The activity measurement device further includes a light reflecting component 30, which is arranged outside the light emitting chamber 10, and at least a part of the light reflecting component 30 is located on the side of the light emitting chamber 10 away from the light detecting component 20, so that part of the fluorescence emitted by the working gas is reflected toward the side of the light detecting component 20. Thus, the light reflecting component 30 can reflect at least part of the fluorescence moving toward the side of the light reflecting component 30 toward the side of the light detecting component 20, and by changing the movement trajectory of the part of the fluorescence, the collection efficiency of the fluorescence by the light detecting component 20 can be greatly increased, so that the detection effect of the light detecting component 20 can be better and the speed can be faster.

[0072] The light reflecting component 30 is a component capable of reflecting fluorescence, and a part of the light reflecting component 30 may be located on the side of the light emitting chamber 10 away from the light detecting component 20 , or the whole of the light reflecting component 30 may be located on the side of the light emitting chamber 10 away from the light detecting component 20 .

[0073] The specific structure and shape of the light reflection component 30 is not limited.

[0074] For example, see Figure 1 and Figure 2The light reflection component 30 includes a reflection cavity 31, and the light detection component 20 and the light emitting cavity 10 are arranged at intervals along the first direction. In the projection plane perpendicular to the first direction, the projection of the light emitting cavity 10 is located within the projection range of the reflection cavity 31. Therefore, the reflection effect of the reflection cavity 31 can be greatly improved, and the collection efficiency of the light detection component 20 for fluorescence can be further improved.

[0075] That is, the reflective cavity 31 at least covers the side of the light emitting cavity 10 away from the light detection assembly 20 along the first direction, so as to reflect more fluorescence to the light detection assembly 20. From the perspective of projection, the projection range of the reflective cavity 31 covers the projection of the light emitting cavity 10.

[0076] The material of the reflective cavity 31 is not limited. For example, the reflective cavity 31 is made of polytetrafluoroethylene, thereby greatly increasing the reflective effect of the reflective cavity 31 .

[0077] In one embodiment, please refer to Figure 1 and Figure 2 , the reflective cavity 31 and the light detection assembly 20 are located on different sides of the light emitting chamber 10. That is, the reflective cavity 31 is not located on the side of the light emitting chamber 10 where the light detection assembly 20 is disposed, and the side of the light emitting chamber 10 where the light detection assembly 20 is disposed is open, which can prevent the reflective cavity 31 from affecting the measurement of the light detection assembly 20.

[0078] In one embodiment, the light-transmitting cavity 11 has a take-in and put-out opening for taking in and putting in the α radiation source 50, and the take-in and put-out opening is on the opposite side of the reflective cavity 31. That is, the reflective cavity 31 is not located on the side of the light-transmitting cavity 11 where the take-in and put-out opening is provided, and the side of the light-transmitting cavity 11 where the take-in and put-out opening is provided is open, so that the reflective cavity 31 can be prevented from affecting the taking in and putting in of the α radiation source 50.

[0079] In one embodiment, please refer to Figure 1 and Figure 2 The surface of the reflective cavity 31 near the light emitting cavity 10 is a part of a spherical surface and is concave toward the side away from the light emitting cavity 10. Thus, the reflection effect of the reflective cavity 31 on the fluorescence can be improved so that it can be better reflected toward the side near the light detection component 20.

[0080] Specifically, at least the surface of the reflective cavity 31 on the side close to the light-emitting cavity 10 is a curved surface, which is actually a part of a spherical surface, and is concave toward the side away from the light-emitting cavity 10 .

[0081] Of course, according to actual conditions, the surface of the reflective cavity 31 facing away from the light-emitting chamber 10 can be a flat surface or a curved surface.

[0082] In one embodiment, the light reflection assembly 30 further includes a first diffuse reflection layer disposed on the side of the reflection cavity 31 close to the light emitting cavity 10. By coating the first diffuse reflection layer on the surface of the reflection cavity 31 close to the light emitting cavity 10, the fluorescence collection efficiency can be further increased.

[0083] In one embodiment, please refer to Figure 1 and Figure 2 The light-transmitting cavity 11 also has an airflow inlet 11b and an airflow outlet 11c, which are respectively located on the inner wall of the light-transmitting cavity 11 on opposite sides of the α radiation source 50. Thus, by using the airflow method to fill the working gas, the working gas with a different density from the air can flow into the light-transmitting cavity 11 at normal pressure faster, so as to drive the air out of the light-transmitting cavity 11.

[0084] The airflow inlet 11b and the airflow outlet 11c are both connected to the accommodating chamber 11a. The airflow inlet 11b is used for the working gas to flow into the accommodating chamber 11a, and the airflow outlet 11c is used for the gas in the accommodating chamber 11a to flow out.

[0085] In one embodiment, please refer to Figure 1 and Figure 2 The light-transmitting cavity 11 also has an airflow inlet 11b and an airflow outlet 11c, and the airflow outlet 11c is located on the top side of the airflow inlet 11b. Thus, after the working gas flows into the light-transmitting cavity 11, the air can be driven out of the light-transmitting cavity 11 more quickly.

[0086] In a specific embodiment, the distance between the airflow inlet 11 b and the α-radiation source 50 is about 30 mm, and the distance between the airflow outlet 11 c and the α-radiation source 50 is greater than 50 mm.

[0087] The sizes of the airflow inlet 11b and the airflow outlet 11c are not limited, for example, the inner diameters of the airflow inlet 11b and the airflow outlet 11c are less than 10 mm.

[0088] In a specific embodiment, the α radiation fluorescence measuring device further includes a high-pressure gas cylinder, which is connected to the air flow inlet 11b for inflation.

[0089] The specific filling speed of the high-pressure gas cylinder can be set according to actual conditions. For example, the high-pressure gas cylinder is filled with working gas from the air flow inlet 11b at a flow rate of 80mL / min for 15 minutes, so that the light-transmitting cavity 11 can be completely filled with working gas, and the purity of the working gas will continue to increase with the increase of the filling time.

[0090] In one embodiment, please refer to Figure 1 and Figure 2The α radiation fluorescence measuring device further includes a darkroom 40, in which the light emitting chamber 10, the light detection assembly 20 and the light reflection assembly 30 are all arranged, and the α radiation fluorescence measuring device further includes a second diffuse reflection layer arranged on the inner surface of the darkroom 40. Thus, the second diffuse reflection layer can reflect the fluorescence of the radiation source emitted to the wall of the darkroom 40 onto the light detection assembly 20, and can further improve the fluorescence collection efficiency of the light detection assembly 20.

[0091] It should be noted that the specific material of the darkroom 40 is not limited. For example, the darkroom 40 is formed by processing with black anodized aluminum material, and the junction between the inside and the outside of the darkroom 40 is sealed to prevent light from penetrating.

[0092] In one embodiment, the coincidence activity measurement device further includes a shielding room 80 , in which the light emitting chamber 10 , the light detection assembly 20 and the gamma-ray detector 60 are all located.

[0093] In one embodiment, please refer to Figure 4 The compliance activity measuring device includes an α fluorescence detector 1 and a γ-ray detector 60 , wherein the α fluorescence detector 1 includes a light emitting chamber 10 and a light detection component 20 .

[0094] In the description of the present application, the description with reference to the terms "in one embodiment", "in some embodiments", "in a specific embodiment", or "exemplary" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In the present application, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0095] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims

1. A coincidence activity measuring device, characterized in that: include: A light-emitting chamber, the light-emitting chamber comprising a light-transmitting cavity having a receiving cavity, and a working gas filled in the receiving cavity, the receiving cavity being used to install an α radiation source, and the working gas being able to emit fluorescence under the radiation of the α radiation source; A light detection component, which is arranged outside the light-emitting chamber and faces the α-radiation source to detect the fluorescence emitted by the working gas; A gamma ray detector is arranged outside the light emitting chamber to detect the gamma rays emitted by the alpha radiation source.

2. The coincidence activity measuring device according to claim 1, characterized in that: The light detection assembly is arranged on one side of the light-transmitting cavity along the circumferential direction, and the gamma-ray detector is arranged on the bottom side of the light-transmitting cavity.

3. The coincidence activity measuring device according to claim 2, characterized in that: The gamma-ray detector is fitted to the bottom of the light-transmitting cavity. At the fitting point between the light-transmitting cavity and the gamma-ray detector, at least a part of the bottom of the light-transmitting cavity is a carbon fiber window.

4. The coincidence activity measuring device according to claim 2, characterized in that: The central axis of the end surface of the gamma-ray detector close to one side of the light-transmitting cavity coincides with the central axis of the light-transmitting cavity, and the alpha radiation source is located on the central axis of the light-transmitting cavity.

5. The coincidence activity measuring device according to claim 2, characterized in that: The accommodating cavity has an installation position for installing an α radiation source, and the distance between the installation position and the inner wall of the light-transmitting cavity is greater than or equal to the range of α particles of the α radiation source.

6. The coincidence activity measuring device according to any one of claims 1 to 5, characterized in that: The coincidence activity measurement device also includes an integrated digital spectrometer, which is respectively connected to the light detection component and the gamma-ray detector signal.

7. The coincidence activity measuring device according to any one of claims 1 to 5, characterized in that: The light detection assembly includes a photomultiplier tube and an optical filter. The optical filter is arranged between the photomultiplier tube and the light emitting chamber, and the center of the photomultiplier tube, the center of the optical filter and the center of the light emitting chamber are coaxially arranged.

8. The coincidence activity measuring device according to any one of claims 1 to 5, characterized in that: The compliance activity measuring device also includes a light reflecting component, which is arranged outside the light emitting chamber, and at least a portion of the light reflecting component is located on a side of the light emitting chamber away from the light detecting component, so that part of the fluorescence emitted by the working gas is reflected toward one side of the light detecting component.

9. The coincidence activity measuring device according to any one of claims 1 to 5, characterized in that: The light-transmitting cavity also has an airflow inlet and an airflow outlet; The airflow inlet and the airflow outlet are respectively located on the inner wall of the light-transmitting cavity on two opposite sides of the α-radiation source; and / or, The air flow outlet is located at the top side of the air flow inlet.

10. The coincidence activity measuring device according to any one of claims 1 to 5, characterized in that: At least part of the light-transmitting cavity is made of ultraviolet fused quartz glass; and / or, The light-emitting chamber further comprises an ultraviolet anti-reflection film, and at least one of the inner surface and the outer surface of the periphery of the light-transmitting cavity is provided with the ultraviolet anti-reflection film.

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