Neutron generator with shielding body

Abstract

The utility model discloses a neutron generator with a shielding body. The neutron generator comprises a shell, a neutron tube and the shielding body, wherein the front end of the shell is connected with a detector; in the first direction from the front end of the shell to the rear end of the shell, the shielding body and the neutron tube are sequentially located in the shell, so that the shielding body is used for shielding gamma rays generated by neutrons directly emitted to the detector from the neutron tube, interference to the detector is reduced, and the detection efficiency is improved. The accuracy of detection data of the detector is improved, and the accuracy of neutron activation analysis data is ensured.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of prompt neutron activation analysis, specifically relates to a neutron generator with shielding body. BACKGROUND

[0002] Prompt neutron activation analysis is a technique for detecting and analyzing elemental composition. It is based on the principle of neutron activation, which emits neutrons from a neutron generator to bombard the elemental atomic nucleus in the sample, so that it excites to form a compound nucleus, and then measures the prompt gamma rays released by the compound nucleus to obtain its characteristic spectrum, and finally determines the composition and content of the elements in the sample. This method has the advantages of high sensitivity, high resolution and non-destructive, and is especially suitable for the identification and analysis of low-Z elements. Prompt neutron activation analysis is commonly used in environmental sample measurement, material science analysis, geological mineral detection and archaeological detection.

[0003] When the neutron tube inside the neutron generator produces neutrons, it emits neutrons in 4π direction, so part of the neutrons will not pass through the sample to be measured and will be directly emitted from the front end of the neutron generator to the detector, producing gamma rays through various reactions, thereby interfering with the detection data of the detector, causing errors in the final analysis data and affecting the measurement accuracy. UTILITY MODEL CONTENT

[0004] In order to solve the above problems existing in the prior art, the utility model provides a neutron generator with shielding body.

[0005] The technical problem to be solved by the utility model is solved by the following technical scheme:

[0006] A neutron generator with shielding body, comprising: a shell, a neutron tube and a shielding body;

[0007] Wherein, the front end of the shell is connected with a detector; along the first direction from the front end of the shell to the rear end of the shell, the shielding body and the neutron tube are located in the shell in turn, so as to shield the gamma rays produced by the neutrons directly emitted from the neutron tube to the detector by using the shielding body.

[0008] Optionally, the shielding body is a tungsten-nickel-iron shielding body.

[0009] Optionally, the shielding body is a shadow cone shielding body; the tip of the shadow cone shielding body faces the detector.

[0010] Optionally, the neutron generator further comprises a transformer and a power supply module;

[0011] The shielding body, the transformer, the neutron tube and the power module are sequentially arranged in the shell along the first direction; the transformer is electrically connected with the power module and the neutron tube; the power module is used for providing high-voltage electricity for the neutron generator; and the transformer is used for converting the high-voltage electricity into working voltage of the neutron tube.

[0012] Optionally, the neutron generator further comprises a metal framework.

[0013] The shielding body, the metal framework, the neutron tube and the power module are sequentially arranged in the shell along the first direction; and the transformer is fixed to the metal framework.

[0014] Optionally, the neutron generator further comprises a metal connecting rod, which connects the neutron tube and the metal framework.

[0015] Optionally, the shielding body is located at a position corresponding to a limiting structure on the shell; and the neutron generator further comprises a spring.

[0016] One end of the spring is abutted against the metal framework, and the other end is abutted against the limiting structure; and the spring is partially sleeved on the shielding body.

[0017] Optionally, a gas connection port is arranged at a rear end of the shell; and the gas connection port is used for vacuumizing the shell and filling sulfur hexafluoride gas into the shell after vacuumizing the shell.

[0018] Optionally, a terminal post is arranged at a front end of the shell; and the terminal post is externally connected with a power supply and is used for supplying power to an ion source of the neutron tube.

[0019] The neutron generator with the shielding body provided by the utility model can shield gamma rays generated by neutrons directly radiating to the detector by arranging the shielding body between the detector and the neutron tube, reduce the interference on the detector, significantly improve the accuracy of the detection data of the detector, and thus ensure the accuracy of the neutron activation analysis data.

[0020] The utility model will be further described in detail below with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a structure schematic view of a neutron generator with a shielding body provided by an embodiment of the utility model;

[0022] Figure 2 is a schematic view of emitting neutrons to bombard a sample to be detected by using the neutron generator provided by the embodiment of the utility model.

[0023] Figure 3is a structural schematic view of another neutron generator with a shielding body provided by the embodiment of the utility model.

[0024] Figure 4 is Figure 3 The partial enlarged view of the position of the shielding body in the neutron generator is shown.

[0025] Reference signs:

[0026] 1, terminal post; 2, shielding body; 3, transformer; 4, neutron tube; 5, shell; 6, power module; 7, terminal head; 8, gas connection; 9, spring; 10, metal framework; 11, metal connecting rod; 12, sample to be measured; 13, detector. DETAILED DESCRIPTION

[0027] The utility model will be further described in detail in combination with specific embodiments, but the implementation of the utility model is not limited to this.

[0028] In order to improve the data accuracy of prompt neutron activation analysis, the embodiment of the utility model provides a neutron generator with a shielding body, as shown in Figure 1 The neutron generator comprises a shell 5, a neutron tube 4 and a shielding body 2.

[0029] The shell 5 is a metal shell, for example, a steel shell, which can be designed as a sealed circular shell, of course, not limited to this. The front end of the shell 5 is connected with the detector 13. In the first direction (X direction) from the front end of the shell 5 to the rear end of the shell 5, the shielding body 2 and the neutron tube 4 are sequentially located in the shell 5, so as to shield the gamma ray generated by the neutron directly emitted from the neutron tube 4 to the detector 13 by the shielding body 2. Figure 1

[0030] In the embodiment of the utility model, the neutron tube 4 is a controllable neutron source, which adopts D-T (deuterium-tritium) reaction to generate 14MeV neutron. Compared with the ordinary chemical isotope neutron source, the neutron yield of this neutron source is high, the monochromaticity of the energy spectrum is good, there is no gamma background, the pulsed neutron can be generated, there is no radioactivity when not working, and the surrounding environment and human body will not be harmed, and the protection is easy, the storage management and transportation are convenient.

[0031] As shown in Figure 2 ​As shown, in the working process of the above neutron generator, the neutrons generated by the neutron tube 4 are emitted in the 4π direction, part of the neutrons (denoted by a) are emitted to the sample to be measured 12, gamma rays are generated through various reactions and are emitted to the detector 13, and are collected by the detector 13; another part of the neutrons (denoted by b) are emitted to the front end of the shell 5, and the gamma rays generated thereby are blocked by the shielding body 2 and cannot be collected by the detector 13. Thus, the shielding body 2 is used to shield the gamma rays generated by the neutrons directly emitted from the neutron tube 4 to the detector 13, thereby reducing the interference to the detector 13 and significantly improving the accuracy of the detection data of the detector 13, thereby ensuring the accuracy of the neutron activation analysis data.

[0032] In addition, the shielding body 2 is integrated in the neutron generator in the embodiment of the utility model, rather than being externally arranged outside the neutron generator, so that the installation, movement and overall control of the neutron generator can be facilitated.

[0033] In one embodiment, the shielding body 2 is preferably a tungsten-nickel-iron shielding body, that is, the shielding body 2 is preferably made of tungsten-nickel-iron alloy. The tungsten-nickel-iron alloy is a high-density alloy with strong anti-radiation performance, and its density is about 1.6 times that of lead, has good plasticity, processability and weldability, has a high neutron inelastic scattering cross section and good gamma ray absorption performance. Therefore, the shielding body 2 made of tungsten-nickel-iron alloy can effectively shield the gamma rays generated by the neutrons directly emitted from the neutron tube 4 to the detector 13.

[0034] In addition, the tungsten-nickel-iron alloy has the characteristics of high strength, high hardness, corrosion resistance and heat resistance, is suitable for harsh environments, and can maintain its physical and chemical properties at high temperatures, and is suitable for high-temperature conditions. Thus, the shielding body 2 can effectively absorb the gamma rays generated by the neutrons from the front end under various conditions, reduce the influence on the sample neutron activation analysis, and improve the accuracy of the data.

[0035] In one embodiment, referring to Figure 3 and Figure 4 As shown, the shielding body 2 can be a shadow cone-shaped shielding body (for example, a shadow cone-shaped tungsten-nickel-iron shielding body), and the tip of the shadow cone-shaped shielding body faces the detector 13.

[0036] In this embodiment, the shadow cone-shaped shielding body can effectively shield the neutrons emitted from the neutron tube 4 to the detector 13 at different angles, thereby improving the shielding effect and further ensuring the accuracy of the detection data and the accuracy of the neutron activation analysis data.

[0037] In one embodiment, referring to Figure 3 As shown, the neutron generator provided by the utility model further comprises a transformer 3 and a power supply module 6.

[0038] Wherein, in the shell 5, along the first direction, in turn, provided with shielding body 2, transformer 3, neutron tube 4 and power module 6;Transformer 3 is electrically connected power module 6 and neutron tube 4;Power module 6 is used to provide high voltage for neutron generator electricity;Transformer 3 is used to convert high voltage into the working voltage of neutron tube 4.

[0039] It can be understood that the neutron tube 4 needs to be powered to emit beam, therefore, the power module 6 is used to provide stable high voltage for neutron generator to ensure its normal operation. Since the power module 6 is a high voltage power module, its output voltage may not be stable, which may affect the beam performance of the neutron generator. Therefore, the transformer 3 is used to convert the high voltage supplied by the power module 6 to the neutron tube 4 into the stable voltage required by the neutron tube 4, so as to ensure that the neutron generator works in a stable voltage range, and improve the reliability and safety of the equipment.

[0040] In addition, the shell can also be provided with a terminal 7, so as to introduce the external power supply into the shell through the terminal 7, so as to be electrically connected with the power module 6.

[0041] In one embodiment, referring to Figure 3 The neutron generator provided by the utility model further comprises a metal framework 10.

[0042] Specifically, in the shell 5, along the first direction, in turn, provided with shielding body 2, metal framework 10, neutron tube 4 and power module 6;Transformer 3 is fixed to the metal framework 10.

[0043] Here, the metal framework 10 is used to fix the transformer 3, which avoids the instability of the transformer 3 in the shell 5, and helps to ensure the stability of the equipment.

[0044] In one embodiment, referring to Figure 3 The neutron generator provided by the utility model further comprises a metal connecting rod 11, which connects the neutron tube 4 and the metal framework 10.

[0045] Exemplarily, a threaded connector can be used to connect the metal connecting rod 11 with the neutron tube 4 and the metal framework 10.

[0046] Here, the metal connecting rod 11 is used to connect the neutron tube 4 and the metal framework 10, which can play a fixing role for the neutron tube 4 and ensure the stability of the equipment.

[0047] In one embodiment, referring to Figure 3 In the shell 5, the position corresponding to the shielding body 2 is provided with a limiting structure on the shell;The neutron generator provided by the utility model further comprises a spring 9;One end of the spring 9 abuts against the metal framework 10, the other end abuts against the limiting structure, and the spring 9 is partially sleeved on the shielding body 2.

[0048] Optionally, as shown in Figure 4 The shell 5 can be designed as a shell structure with different diameters, wherein the diameter of the shell 5 corresponding to the positions where the metal framework 10, the neutron tube 4 and the power module 6 are located is D, and the diameter of the shell 5 corresponding to the position where the shielding body 2 is located is d, and D>d. In this way, the position on the shell 5 where the diameter changes from D to d can be used as a limiting structure to abut against the spring 9. Of course, the specific implementation of the limiting structure is not limited to this.

[0049] Optionally, as shown in Figure 4 The end of the metal framework 10 close to the spring 9 is protruded, and the spring 9 is sleeved on the part of the protruded structure to abut against the main body structure of the metal framework 10.

[0050] In this embodiment, by introducing the spring 9 in the shell 5, the metal framework 10 and the shell 5 can be provided with buffering and damping.

[0051] In one embodiment, the rear end of the shell 5 is provided with a gas connection port 8; the gas connection port 8 is used for vacuumizing the shell 5 and filling sulfur hexafluoride gas into the shell 5 after vacuumizing the shell 5.

[0052] Here, to ensure the stable operation of the circuits (the neutron tube 4, the transformer 3 and the power module 6) inside the neutron generator, the arc phenomenon of the circuits inside the shell 5 can be effectively prevented by vacuumizing the inside of the shell 5 through the gas connection port 8 and then filling sulfur hexafluoride gas.

[0053] In one embodiment, the front end of the shell 5 can also be provided with a terminal post 1; the terminal post 1 is externally connected to a power supply for supplying power to the ion source of the neutron tube 4.

[0054] In summary, the neutron generator with a shielding body provided by the embodiments of the present application has an integrated and compact design, so that the whole neutron generator is portable and easy to move, without the need for additional installation of shielding components, and the operation is simple, which greatly simplifies the operation and installation process. The operator does not need to perform complex installation and adjustment, but only needs to simply connect and start to use, which significantly improves the work efficiency on the basis of significantly improving the accuracy of the detection data of the detector, reduces the risk of on-site operation and the possibility of equipment damage, and improves the stability and safety of the overall system.

[0055] It should be noted that other conventional components contained in the neutron generator, such as accelerators, ion sources, targets, gas pressure adjusting systems and shielding devices, can be referred to related prior art, and the embodiments of the present application will not be described in detail.

[0056] It should be noted that the terms "first", "second", and so on are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the utility model described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the utility model. Instead, they are only examples of devices and methods consistent with some aspects of the utility model.

[0057] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in the specification.

[0058] Although the utility model is described herein in conjunction with various embodiments, those skilled in the art can understand and implement other changes of the disclosed embodiments by viewing the drawings and disclosure in the process of implementing the claimed utility model. In the description of the utility model, the word "comprising" does not exclude other components or steps, "one" or "a" does not exclude multiple cases, and "multiple" means two or more, unless otherwise explicitly specified. In addition, some measures are recorded in different embodiments, but this does not mean that these measures cannot be combined to produce good results.

[0059] In the description of the utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0060] In the utility model, unless another definite provision and limitation, the terms "mount", "link", "connect", "fix" and so on should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated; can be mechanical connection, also can be electrical connection; can be direct connection, also can be indirectly connected through intermediate medium, can be the communication of two elements or the interaction of two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to specific circumstances.

[0061] In the utility model, unless another definite provision and limitation, the first feature is "on" or "under" the second feature can include that the first and second features are in direct contact, also can include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature is "on", "above" and "on the surface of" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than the second feature. The first feature is "under", "below" and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than the second feature.

[0062] The above is further detailed description of the utility model in combination with specific preferred embodiments, and the specific implementation of the utility model cannot be limited to these descriptions. For ordinary skilled in the art to which the utility model belongs, on the premise of not departing from the concept of the utility model, a number of simple deductions or substitutions can also be made, and all should be regarded as belonging to the protection scope of the utility model.

Claims

1. A neutron generator with a built-in shield, characterized in that, The application relates to a neutron generator. The neutron generator comprises a shell, a neutron tube and a shielding body. The front end of the shell is connected with a detector. The shielding body and the neutron tube are sequentially arranged in the shell along a first direction from the front end of the shell to the rear end of the shell, so that the shielding body shields the gamma ray generated by the neutron directly shot from the neutron tube to the detector.

2. The self-shielded neutron generator of claim 1, wherein, The shielding body is a tungsten-nickel-iron shielding body.

3. The self-shielded neutron generator of claim 1, wherein, The shielding body is a shadow cone-shaped shielding body, and the tip of the shadow cone-shaped shielding body is directed to the detector.

4. The self-shielded neutron generator of claim 1, wherein, The neutron generator further comprises a transformer and a power module. The shielding body, the transformer, the neutron tube and the power module are sequentially arranged in the shell along the first direction, the transformer is electrically connected with the power module and the neutron tube, the power module is used for providing high-voltage electricity for the neutron generator, and the transformer is used for converting the high-voltage electricity into the working voltage of the neutron tube.

5. The self-shielded neutron generator of claim 4, wherein, The neutron generator further comprises a metal framework. The shielding body, the metal framework, the neutron tube and the power module are sequentially arranged in the shell along the first direction, and the transformer is fixed to the metal framework.

6. The self-shielded neutron generator of claim 5, wherein, The neutron generator further comprises a metal connecting rod, and the metal connecting rod connects the neutron tube and the metal framework.

7. The self-shielded neutron generator of claim 5, wherein, The position of the shielding body corresponds to a limiting structure arranged on the shell, and the neutron generator further comprises a spring. One end of the spring is abutted against the metal framework, and the other end of the spring is abutted against the limiting structure, and the spring is partially sleeved on the shielding body.

8. The self-shielded neutron generator of claim 1, wherein, The rear end of the shell is provided with a gas connection port, the gas connection port is used for vacuumizing the shell and filling sulfur hexafluoride gas into the shell after the shell is vacuumized.

9. The self-shielded neutron generator of claim 1, wherein, The front end of the shell is provided with a terminal post, the terminal post is externally connected with a power supply and is used for supplying power for the ion source of the neutron tube.

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