Target system and method of manufacturing a radioisotope

Abstract

The present application relates to the field of medical radioisotope production, and discloses a target system and a method for manufacturing radioisotopes, the target system comprising: a target chamber, an on-off control member, a target body and a cooling device, the target chamber being provided with a beam entry port and a vacuum extraction interface; the on-off control member being arranged on the target chamber and used for opening or closing the beam entry port; the target body being arranged in the target chamber; the cooling device being connected with the target body and used for heat exchange of the target body; the target body comprising a target sheet, a support frame and a transmission shuttle, an end of the transmission shuttle opposite to the beam entry port being open, the support frame being arranged in the transmission shuttle, the target sheet being arranged on the support frame, a front surface of the target sheet being provided with a target material layer, a back surface of the target sheet being provided with a cooling flow channel, the cooling flow channel being communicated with the cooling device, and the target sheet being inclined relative to an axis direction of the transmission shuttle. The target system of the present application can omit the vacuum film and the helium cooling of the traditional system, reduce energy loss, improve beam utilization, reduce beam loss and system maintenance cost, and improve the reliability of the target system.

Description

Technical Field

[0001] This invention relates to the field of medical radioisotope production technology, and in particular to a target system and a method for manufacturing radioisotopes. Background Technology

[0002] Of the more than one hundred elements discovered by humans to date, there are approximately three hundred stable isotopes and more than one thousand five hundred radioactive isotopes. Isotope technology is now widely used in many fields, including agriculture, industry, medicine, geology, and archaeology. In nuclear medicine, radioactive isotope tracing technology is often used to scan organs such as the thyroid, liver, kidneys, brain, heart, and pancreas to diagnose and treat diseases such as tumors. This method is simple and safe. Radiopharmaceuticals, represented by radionuclides such as technetium-99m, fluorine-18, and iodine-131, have long been widely used in clinical diagnosis and treatment. PET (positron emission tomography) and SPECT (single-photon emission computed tomography) imaging are typical applications of radioactive isotopes.

[0003] Radioactive isotopes are mainly obtained through reactor irradiation, accelerator preparation, separation of natural isotopes, extraction from high-level radioactive waste, and generator preparation. Cyclotrons, with their ability to accelerate a wide variety of particles, broad energy coverage, and high average beam intensity, are one of the core pieces of equipment for preparing medical radioactive isotopes and are currently frequently used in this field. 18 F-FDG (fluorine-18 labeled fluorodeoxyglucose) is a drug. Accelerators prepare radioactive isotopes by accelerating a particle beam to bombard a target, triggering a nuclear reaction. The device used to contain the target and receive the beam irradiation is called the target system. Based on the physical state of the target material, target systems can be divided into three categories: solid targets, liquid targets, and gas targets. Astatine-211, copper-64, gallium-68, and zirconium-89 are examples of radionuclides prepared using solid targets.

[0004] Among them, Astatine-211 ( 211 The half-life of At (T) 1 / 2 Astatine has a decay time of 7.2 hours, a dual decay pathway, and releases an alpha particle with each decay. It is one of the most researched alpha nuclides and could be used for targeted alpha therapy. Astatine itself belongs to the halogen group and has chemical properties similar to iodine. It is volatile, with a melting point of approximately 300°C and a boiling point of approximately 340°C. Currently, production... 211 At(T 1 / 2 =7.2h) The most common approach is to use a cyclotron to bombard high-purity natural bismuth with high-current alpha particles, through nuclear reactions. 209 Bi(α, 2n) 211The preparation was completed at At. The initial incident energy for this nuclear reaction was 20.7 MeV. It should be noted that the nuclear reaction will be triggered when the incident energy exceeds 28.6 MeV. 209 Bi(α, 3n) 210 At(T 1 / 2 =8.1h), and 210 At decay produces long-lived nuclides. 210 Po(T 1 / 2 =138.4d), therefore, control is required during the production process. 210 The amount of At produced. Considering both product yield and quantity, the optimal incident energy range for preparing astatine-211 is 28 MeV to 29 MeV. Bismuth metal has extremely low thermal conductivity (7.97 W·K). -1 ·m -1 With a melting point of only 271℃, the thermal management and cooling of bismuth targets are crucial. 211 Key points and challenges in the design process of At-target systems.

[0005] In the mass production of Astatine-211, the external target system is one of the current mainstream technical approaches. Existing external target systems generally set up a vacuum membrane between the target chamber and the accelerator's main vacuum chamber to separate the accelerator vacuum environment from the helium environment. Its cooling usually adopts a "helium cooling before the target + water cooling after the target" scheme. That is, helium is mainly used to cool the surface of the vacuum membrane through a conduit before the target, while carrying away a small amount of heat from the bismuth target. After the target, water cooling is used to remove most of the surface heat load from the bismuth target, avoiding excessively high target surface temperature that could lead to the volatilization and loss of Astatine-211.

[0006] However, this traditional structure has the following shortcomings: First, the alpha particle beam generated by the accelerator needs to pass through a vacuum membrane and a helium environment before it can irradiate the target material, which will increase the beam energy loss and reduce the beam utilization rate. For example, existing literature has recorded that the energy loss of a 30 MeV alpha particle beam after passing through a 40 μm carbon film window is about 1.42 MeV, and the energy loss after passing through 60 mm of helium (1.25 atm) is about 0.34 MeV, and the final energy incident on the target surface is only 28.34 MeV.

[0007] Secondly, alpha particles have a mass four times that of protons and a charge twice that of protons. The displacement damage (DPA) they cause to vacuum membranes is much greater than that caused by protons. Long-term exposure of vacuum membranes to alpha beams can lead to problems such as radiation hardening, embrittlement, heat generation and thermal stress accumulation, blistering and peeling, and even perforation and vacuum leakage. Under high-intensity alpha beam conditions of 50μA to 200eμA, the effective service life of vacuum membranes may be shortened to several months, significantly increasing maintenance time and costs.

[0008] Third, helium cooling can only remove about one-tenth of the total heat load. Core heat dissipation still relies on target back water cooling. However, the helium supply system has a complex structure and requires multiple subsystems such as filtration, pressurization, flow control, and heat exchange. It also requires regular helium refilling or replacement of helium cylinders, resulting in high maintenance costs.

[0009] Therefore, there is an urgent need for a target system that can reduce beam loss, control bismuth target temperature, and reduce system maintenance costs. Summary of the Invention

[0010] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one object of the present invention is to provide a target system that can reduce beam loss and system maintenance costs, and improve the reliability of the target system while achieving controllable target temperature.

[0011] The present invention also aims to provide a method for manufacturing a radioactive isotope for use with the target system described above.

[0012] The target system according to an embodiment of the present invention is used for preparing... 211 At includes: a target chamber, the target chamber having a beam inlet and a vacuum interface; an on / off control component, the on / off control component being disposed on the target chamber for opening or closing the beam inlet; a target body, the target body being disposed within the target chamber; a cooling device, the cooling device being connected to the target body for heat exchange of the target body; the target body includes a target plate, a support frame, and a transfer shuttle, the end of the transfer shuttle facing the beam inlet being open, the support frame being disposed within the transfer shuttle, the target plate being disposed on the support frame, the front side of the target plate having a target material layer, the back side of the target plate having a cooling channel, the cooling channel being connected to the cooling device, and the target plate being inclined relative to the axial direction of the transfer shuttle so that the target material layer corresponds to the beam inlet.

[0013] According to the target system of the present invention, this structure can eliminate the need for vacuum membrane and helium cooling in traditional systems. During beam irradiation, the particle beam does not need to pass through the vacuum membrane and helium environment, which can avoid the energy loss caused by the vacuum membrane in traditional solutions, improve beam utilization, simplify the overall structure, and eliminate the operational and maintenance burden caused by irradiation damage to the vacuum membrane and helium supply. At the same time, it achieves multiple optimization goals of high beam utilization, efficient thermal management and low maintenance cost.

[0014] In some embodiments of the present invention, the target chamber includes a first part, a second part, and a third part connected in sequence. The end of the first part away from the second part forms the beam inlet. The on / off control element is disposed on the first part. The vacuum interface is disposed on the second part. The target body and the cooling device are disposed on the third part. The target body seals the connection between the third part and the second part.

[0015] In some embodiments of the present invention, the third part is provided with a first region and a second region inside, and a transmission interface is provided at the end of the third part away from the second part. The transmission interface is connected to the second region. The target is disposed in the first region. The target and the transmission interface are arranged in a parallel direction along the first region and the second region. The target system includes a disassembly mechanism. The disassembly mechanism drives the target to move from the first region to the second region.

[0016] In some embodiments of the present invention, the included angle between the axis of the target plate and the axis of the transmission shuttle is 5° to 45°.

[0017] In some embodiments of the present invention, the target chamber is provided with an installation port, the cooling device is installed in the installation port, the target system includes a disassembly mechanism, the disassembly mechanism includes a first driving member and a second driving member, the first driving member drives the cooling device to engage or disengage from the support frame along the axial direction of the transfer shuttle, the second driving member drives the transfer shuttle to move along the axial direction perpendicular to the transfer shuttle, the target chamber is provided with a transfer interface, the transfer interface and the first driving member are located on the same side of the target chamber.

[0018] In some embodiments of the present invention, the support frame is provided with a groove, the groove having a bottom surface, the bottom surface being parallel to the target plate, the bottom surface being provided with an inlet and an outlet for conveying cooling medium, the target plate being disposed in the groove, a gap being formed between the back surface of the target plate and the bottom surface of the groove, and the cooling device having an inlet channel and an outlet channel for conveying cooling medium, the inlet channel being connected to the inlet, and the outlet channel being connected to the outlet.

[0019] In some embodiments of the present invention, the temperature of the cooling medium at the inlet is less than or equal to 20°C, and the flow rate is greater than or equal to 2L / min.

[0020] According to an embodiment of the present invention, a method for manufacturing a radioactive isotope is provided, which uses a target system as described in any of the preceding claims to prepare the radioactive isotope. The method includes: connecting the beam inlet of the target chamber to the outlet of an accelerator; keeping the on / off control device in a closed state and evacuating the target chamber through the vacuum port to make the vacuum level in the target chamber consistent with the vacuum level in the vacuum chamber of the accelerator; opening the on / off control device to connect the target chamber with the vacuum chamber of the accelerator; introducing the beam from the accelerator into the target chamber and bombarding the target body, and controlling the cooling device to cool the target body; and closing the on / off control device and the vacuum port after irradiation.

[0021] According to the method for manufacturing radioactive isotopes of the present invention, by employing the aforementioned target system, direct beam bombardment of the target can be achieved in a high-vacuum, window-free environment. This effectively reduces beam energy loss, improves beam utilization, lowers system maintenance costs, and ensures the stability and repeatability of isotope yield. Simultaneously, a cooling device is activated during irradiation to ensure the target remains structurally stable under thermal load, preventing target material degradation or radioactive product loss due to overheating, further guaranteeing the stability and repeatability of isotope yield.

[0022] In some embodiments of the present invention, in the step of introducing the beam of the accelerator into the target chamber and bombarding the target, the emitted beam of the accelerator is an alpha particle beam, and the target material of the target is bismuth, in order to prepare... 211 At.

[0023] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a three-dimensional structural diagram of the target system provided in some embodiments of the present invention; Figure 2 A front view of a target system provided for some embodiments of the present invention; Figure 3 Simulation results of the temperature distribution of the target sheet provided in some embodiments of the present invention; Figure 4 A side view of a target system provided for some embodiments of the present invention; Figure 5 for Figure 4 A sectional view taken along direction AA; Figure 6 This is a schematic diagram of the three-dimensional structure of the target provided in some embodiments of the present invention; Figure 7 Exploded views of the target structure provided in some embodiments of the present invention; Figure 8 Top view of a target provided for some embodiments of the present invention; Figure 9 A front view of a target provided for some embodiments of the present invention; Figure 10 A bottom view of the target provided for some embodiments of the present invention; Figure 11 for Figure 5 A magnified view of a portion of point I; Figure 12 This is a flowchart illustrating a method for manufacturing radioactive isotopes according to some embodiments of the present invention.

[0025] Figure label: 100. Target system; 10. Target chamber; 10a. Beam inlet; 10b. Mounting port; 101. Vacuum interface; 11. First part; 12. Second part; 13. Third part; 13a. First area; 13b. Second area; 131. Transmission interface; 20. On / off control components; 30. Target body; 31. Target sheet; 311. Target material layer; 312. Cooling channel; 32. Support frame; 32a. Groove; 32b. Groove bottom surface; 32c. Inlet; 32d. Outlet; 33. Transfer shuttle; 331. Transfer shuttle cover; 332. Transfer shuttle shell; 40. Cooling device; 40a. Inlet channel; 40b. Outlet channel; 50. Disassembly mechanism; 51. First driving component; 511. Connecting sleeve; 52. Second driving component. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0027] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not 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, they should not be construed as limitations on this invention.

[0028] Furthermore, features specified as "first" or "second" may explicitly or implicitly include one or more of the same feature, used to distinguish and describe features, without any order or distinction of importance.

[0029] In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] The following is for reference. Figures 1-12 The target system 100 of an embodiment of the present invention is described.

[0032] like Figures 1 to 10 As shown, the target system 100 according to an embodiment of the present invention is used for preparing... 211 The system includes: a target chamber 10, an on / off control component 20, a target body 30, and a cooling device 40. The target chamber 10 is provided with a beam inlet 10a and a vacuum interface 101. The on / off control component 20 is located on the target chamber 10 and is used to open or close the beam inlet 10a. The target body 30 is located inside the target chamber 10. The cooling device 40 is connected to the target body 30 and is used for heat exchange of the target body 30. The target body 30 includes a target plate 31, a support frame 32, and a transfer shuttle 33. The end of the transfer shuttle 33 facing the beam inlet 10a is open. The support frame 32 is located inside the transfer shuttle 33. The target plate 31 is located on the support frame 32. The front side of the target plate 31 is provided with a target material layer 311, and the back side of the target plate 31 is provided with a cooling channel 312. The cooling channel 312 is connected to the cooling device 40. The target plate 31 is inclined relative to the axial direction of the transfer shuttle 33 so that the target material layer 311 corresponds to the beam inlet 10a.

[0033] The target chamber 10 refers to a sealed cavity structure used to house the target 30 and provide a beam irradiation environment. The target chamber 10 is equipped with a beam inlet 10a and a vacuum port 101, and its cross-sectional shape can be, but is not limited to, circular, polygonal, and irregular shapes. The beam inlet 10a is used to connect to the beam outlet of the accelerator, while the vacuum port 101 is used to connect to an external vacuum pump unit to independently evacuate the interior of the target chamber 10 before irradiation, ensuring that its vacuum level is consistent with or close to that of the accelerator's main vacuum chamber, thus preventing gas backflow or beam scattering caused by pressure difference.

[0034] The on / off control component 20 can refer to a component that controls the opening or closing of the beam inlet 10a, and can be, but is not limited to, a slide gate valve, ball valve, butterfly valve, gate valve, etc. For example, the on / off control component 20 can be a slide gate valve, which has a compact structure, good sealing performance, and can be quickly opened and closed in a high vacuum environment, effectively isolating the accelerator's main vacuum chamber from the target chamber 10. Before beam irradiation, the on / off control component 20 is in the closed state, ensuring that the target chamber 10 can be evacuated independently; after the vacuum level of the target chamber 10 reaches the standard, the on / off control component 20 is opened, allowing the beam to smoothly enter the target chamber 10 to bombard the target 30. After irradiation, the on / off control component 20 is promptly closed to prevent radioactive gases or volatile products (such as astatine-211) from diffusing into the accelerator system, ensuring equipment safety and operator protection.

[0035] The target 30 can refer to the core component used to support the target material and receive beam irradiation to generate the target radioactive isotope, and can be, but is not limited to, a bismuth target or a lead target, etc. For example, the target 30 is a bismuth target, and the accelerator's emission beam is an alpha particle beam. The alpha particle beam bombards the bismuth target, enabling the preparation of... 211 At. In the above technical solution, the target body 30 includes a target plate 31, a support frame 32, and a transfer shuttle 33. The target plate 31 can be made of, but is not limited to, aluminum, copper, gold, silver, or other metals with good heat dissipation. The target material layer 311 can be made of, but is not limited to, bismuth, lead, etc. For example, the target plate 31 is made of aluminum with a thickness of 6 mm, and the target material layer 311 is a bismuth layer. The bismuth layer can be processed by vacuum evaporation, magnetron sputtering, niobium film sealing, etc., and its areal density is 5 mg / cm³. 2 ~30mg / cm 2This design avoids both excessively high target density leading to overheating of the target sheet 31 and insufficient target radioisotope yield due to insufficient surface density. A cooling channel 312 is located on the back of the target sheet 31 and connects to the cooling device 40 to form a cooling circuit, directly dissipating heat from the target sheet 31. This enhances the cooling effect, avoids the risk of target material melting or peeling due to localized overheating, ensures structural integrity and isotope yield stability under long-term beam irradiation, and improves the reliability of the target system 100. Simultaneously, the target sheet 31 is tilted relative to the axis of the transmission shuttle 33, causing the beam to be incident on the surface of the target layer 311 at a non-perpendicular angle. This effectively increases the effective path length of the beam within the target material, increases nuclear reaction yield, and further improves the reliability of the target system 100. The cooling channel 312 can be, but is not limited to, a fractal topology or a microchannel array. For example, the cooling channel 312 can be multiple parallel channels with open ends, or it can be a serpentine channel with a channel inlet and a channel outlet. Optionally, the transfer shuttle 33 may include a transfer shuttle housing 332 and a transfer shuttle cover 331, which are connected by threads. The target plate 31 is placed on the support frame 32 and tightened by threads to achieve a detachable connection between the transfer shuttle housing 332 and the transfer shuttle cover 331.

[0036] The cooling device 40 can refer to a device used to dissipate heat from the target 30. It is in direct or indirect contact with the target 30 and uses a circulating cooling medium to promptly remove the heat generated during irradiation. Optionally, the cooling medium is deionized water.

[0037] In the above technical solution, the beam inlet 10a is connected to the accelerator's beam outlet. Before beam irradiation, the on / off control element 20 controls the beam inlet 10a to close. The vacuum pump group independently evacuates the target chamber 10 through the vacuum port 101, making the vacuum level inside the target chamber 10 consistent with or close to the accelerator's main vacuum chamber. Then, the on / off control element 20 is controlled to open the beam inlet 10a, directly connecting the target chamber 10 with the accelerator's main vacuum chamber to form a unified vacuum. The particle beam directly enters the target chamber 10 to bombard the target 30, producing the target radioactive isotope. After irradiation, the on / off control element 20 and the vacuum pump group are turned off, isolating the target chamber 10 from the accelerator to prevent radioactive material backflow. Simultaneously, during beam irradiation, the cooling device 40 exchanges heat with the target 30 to cool it. (Note: The last sentence appears to be incomplete and possibly refers to a reference.) Figure 3 The target 30 is a bismuth target. When the accelerator emits an alpha particle beam of 30 MeV and 50 eμA, the peak temperature of the bismuth target is 182.34℃ during the bombardment of the bismuth target, which is lower than the melting point of bismuth, 271℃. The pure water cooling (helium-free cooling) solution of this application can meet the thermal management requirements of the alpha particle beam under high power density irradiation and avoid target material melting or structural failure.

[0038] Optionally, the vacuum port 101 can be fitted with two activated carbon gas filters in series as an additional safety measure. At the same time, the air discharged from the exhaust pipe in the cyclotron chamber is also fitted with an activated carbon gas filter to further ensure the safety of personnel and equipment.

[0039] According to the target system 100 of the present invention, this structure eliminates the need for a vacuum membrane and helium cooling in traditional systems. During beam irradiation, the particle beam does not need to pass through the vacuum membrane and helium environment, which avoids the energy loss caused by the vacuum membrane in traditional solutions, improves beam utilization, simplifies the overall structure, and eliminates the operational and maintenance burden caused by irradiation damage to the membrane window and helium supply. At the same time, it achieves multiple optimization goals of high beam utilization, efficient thermal management and low maintenance cost.

[0040] In some embodiments of the present invention, reference is made to Figure 2 and Figure 5 The target chamber 10 includes a first part 11, a second part 12 and a third part 13 connected in sequence. The end of the first part 11 away from the second part 12 forms a beam inlet 10a. The on / off control element 20 is provided on the first part 11, the vacuum interface 101 is provided on the second part 12, the target body 30 and the cooling device 40 are provided on the third part 13, and the target body 30 seals the connection between the third part 13 and the second part 12.

[0041] The cross-sectional shapes of the first part 11, the second part 12, and the third part 13 can be the same or different. For example, the first part 11 can adopt a circular cross-section matching the accelerator beam pipe, the second part 12 can be designed as rectangular or elliptical to facilitate the arrangement of the vacuum port 101, and the third part 13 can be optimized into a larger cavity structure according to the installation space requirements of the target 30. At the same time, the target 30 seals the connection between the third part 13 and the second part 12, so that the internal spaces of the target 30, the first part 11, and the second part 12 together form a sealed cavity. Thus, when the on / off control element 20 is closed, the sealed cavity is kept in a vacuum state through the vacuum port 101, allowing the particle beam to directly enter the sealed cavity to bombard the target 30 and generate the target radioactive isotope. Therefore, the third part 13 can be a frame structure or a sealed structure, as long as it is ensured that its connection with the second part 12 is reliably sealed by the target 30.

[0042] In the above technical solution, the first part 11 is dedicated to beam introduction and vacuum isolation, the second part 12 centrally houses the vacuum pumping interface 101, and the third part 13 serves as the core area for target body 30 installation and thermal management. This not only facilitates the independent design and maintenance of each functional module but also effectively avoids mutual interference between the vacuum pumping path and the beam channel, improving the stability and reliability of the target system 100. Simultaneously, the target body 30 is sealed at the connection between the third part 13 and the second part 12, simplifying the sealing structure, reducing potential leakage points, and further improving the reliability of the target system 100.

[0043] In some embodiments of the present invention, reference is made to Figure 2 and Figure 5 The third part 13 has a first region 13a and a second region 13b inside. The end of the third part 13 away from the second part 12 is provided with a transmission interface 131, which is connected to the second region 13b. The target 30 is located in the first region 13a. The target 30 and the transmission interface 131 are arranged in a parallel direction along the first region 13a and the second region 13b. The target system 100 includes a disassembly mechanism 50, which drives the connected target 30 to move the target 30 from the first region 13a to the second region 13b.

[0044] The "side-by-side direction" can be used as a reference. Figure 2 The disassembly mechanism 50 can refer to a device that can move the target 30 from the first region 13a to the second region 13b. After the irradiation task is completed, the on / off control element 20 is turned off to isolate the accelerator main vacuum chamber. Then the disassembly mechanism 50 is activated, driving the target 30 to move from the first region 13a located inside the third part 13 in a parallel direction into the second region 13b, so that the target 30 is in the space communicating with the transmission interface 131. The target 30 can be taken out and transported to the hot chamber through the transmission interface 131 by an external robot or automated device for subsequent isotope extraction or target material recovery.

[0045] In the above technical solution, by setting up a first region 13a and a second region 13b, and cooperating with the disassembly mechanism 50 and the transmission interface 131, the target 30 can be quickly replaced or removed, shortening downtime, improving system operating efficiency, reducing the risk of exposure to radioactive materials, and improving the reliability of the target system 100.

[0046] In some embodiments of the present invention, reference is made to Figure 5 and Figure 7 The included angle between the axes of the target plate 31 and the transmission shuttle 33 is 5°~45°.

[0047] The included angle between the axes of the target plate 31 and the transmission shuttle 33 can be, but is not limited to, 5°, 15°, 25°, 35°, 45°, etc.

[0048] In the above technical solution, by setting the axis of the target plate 31 and the transmission shuttle 33 to an inclination angle of 5° to 45°, it can avoid the projection of the target plate 31 on the cross section of the transmission shuttle 33 being too small due to the angle being too small, so that the beam only partially bombards the target plate 31. It can also avoid the reduction of the effective irradiation area of ​​the beam due to the angle being too large, so that the beam concentrates and bombards the same place on the target plate 31, resulting in concentrated heat and causing local overheating. This achieves uniform deposition and efficient utilization of beam energy in the target material layer 311, and improves the reliability of the target system 100.

[0049] In some embodiments of the present invention, reference is made to Figure 2 and Figure 5 The target chamber 10 is provided with an installation port 10b, and the cooling device 40 is installed in the installation port 10b. The target system 100 includes a disassembly mechanism 50, which includes a first driving member 51 and a second driving member 52. The first driving member 51 drives the connected cooling device 40 to engage or disengage the cooling device 40 from the support frame 32 along the axial direction of the transfer shuttle 33. The second driving member 52 drives the connected transfer shuttle 33 to move along the axial direction perpendicular to the transfer shuttle 33. The target chamber 10 is provided with a transfer interface 131, and the transfer interface 131 and the first driving member 51 are located on the same side of the target chamber 10.

[0050] The first drive unit 51 and the second drive unit 52 can be, but are not limited to, a cylinder, a hydraulic cylinder, an electric actuator, or a linear motor, or other drive devices capable of providing precise displacement control. Meanwhile, since secondary radiation generated by the accelerator's magnetic field and beam irradiation can interfere with electronic components, the first drive unit 51 and the second drive unit 52 are preferably pneumatic components such as cylinders to effectively avoid this problem.

[0051] The second driving component 52 is provided with a connecting sleeve 511 near the support frame 32 (see...). Figure 11The transfer shuttle 33 is located inside the connecting sleeve 511. When the target 30 is replaced after its work is completed, the cooling medium inside the target 30 is first emptied. Then, the cooling device 40 is driven by the first driving member 51 to move away from the target 30 along the axial direction of the transfer shuttle 33, so that the cooling device 40 is separated from the support frame 32. Then, the transfer shuttle 33 is driven by the second driving member 52 to move along the direction perpendicular to its axis, so that the target 30 is moved from the first region 13a to the vicinity of the transfer interface 131 in the second region 13b. The transfer interface 131 is connected to the pneumatic transfer pipe. A negative pressure is generated inside the pneumatic transfer pipe. The target 30 is transported to the hot chamber for subsequent processing in sequence through the transfer interface 131 and the pneumatic transfer pipe. By generating positive pressure inside the pneumatic transmission pipe, a new target 30 can be driven into the connecting sleeve 511 via the transmission interface 131. Then, the second drive member 52 reverses its action, pushing the new target 30 back to the predetermined working position in the first region 13a. Then, the first drive member 51 pushes the cooling device 40 to reset along the axial direction. The cooling device 40 is combined with the support frame 32 to achieve cooling when the target 30 is working.

[0052] In the above technical solution, the cooling device 40 and the target 30 can be disconnected and connected through the cooperation of the first driving component 51 and the second driving component 52, and the bismuth target can be transferred as a whole to the transmission end of the pneumatic transmission system, thereby realizing the fully automatic replacement process of the target 30. At the same time, this process does not require personnel operation, reduces the risk of radiation exposure, and improves the continuity and safety of the target system 100 operation.

[0053] In some embodiments of the present invention, reference is made to Figure 7 and Figure 11 The support frame 32 is provided with a groove 32a, the groove 32a has a bottom surface 32b, the bottom surface 32b is arranged parallel to the target plate 31, the bottom surface 32b is provided with an inlet 32c and an outlet 32d for conveying the cooling medium, the target plate 31 is disposed in the groove 32a, and a gap is formed between the back of the target plate 31 and the bottom surface 32b, the cooling device 40 has an inlet channel 40a and an outlet channel 40b for conveying the cooling medium, the inlet channel 40a is connected to the inlet 32c, and the outlet channel 40b is connected to the outlet 32d.

[0054] The cross-sectional shapes of inlet 32c and outlet 32d can be, but are not limited to, circles, polygons, and irregular shapes, etc.

[0055] A gap is formed between the back surface of the target plate 31 and the bottom surface 32b of the groove. The cooling medium can enter the cooling channel 312 through the inlet 32c from the inlet channel 40a and flow through the cooling channel 312 to cool the target plate 31. And / or, the cooling medium can enter the gap through the inlet channel 40a and flow through the gap to cool the target plate 31.

[0056] In the above technical solution, by setting a cooling path that forms a gap with the back of the target 31 within the groove 32a of the support frame 32, not only can directional and efficient heat dissipation be achieved using the cooling channel 312, but the flow of the medium within the gap can also achieve uniform cooling of the entire target 31, further improving thermal management capabilities. This effectively mitigates the formation of local hot spots under high-power beam irradiation, preventing deformation of the target 31 or cracking of the target material layer 311 due to thermal stress concentration, thereby ensuring the stability of isotope production. Simultaneously, the groove 32a can also limit the target 31, preventing it from detaching from the support frame 32 and ensuring its stable posture during beam bombardment and cooling medium flow. This prevents displacement caused by vibration or thermal expansion from affecting beam alignment accuracy, further ensuring the stability of isotope production.

[0057] In some embodiments of the present invention, reference is made to Figure 5 and Figure 11 The temperature of the cooling medium at inlet 32c is less than or equal to 20℃, and the flow rate is greater than or equal to 2L / min.

[0058] In the above technical solution, by controlling the temperature of the cooling medium at the inlet 32c to 20°C or below and maintaining a flow rate of not less than 2L / min, the heat generated by the target plate 31 can be effectively removed under high beam power conditions, ensuring that the working temperature of the target layer 311 is within a safe threshold, avoiding target material volatilization, melting or structural failure due to excessive temperature rise, and improving the reliability of the target system 100.

[0059] like Figure 12 As shown, an embodiment of the present invention also provides a method for manufacturing a radioactive isotope, which uses a target system 100 as described in any of the preceding embodiments to prepare the radioactive isotope. The method includes: Step S1: Connect the beam inlet of the target chamber 10 to the outlet of the accelerator.

[0060] Step S2: Keep the on / off control element 20 in the closed state, and evacuate the target chamber 10 through the vacuum port 101 to make the vacuum level in the target chamber 10 consistent with the vacuum level in the accelerator's vacuum chamber.

[0061] Step S3: Open the on / off control component 20 to connect the target chamber 10 with the vacuum chamber of the accelerator.

[0062] Step S4: Introduce the accelerator beam into the target chamber 10 and bombard the target 30, and control the cooling device 40 to cool the target 30.

[0063] Step S5: After irradiation ends, turn off the on / off control device 20 and the vacuum port 101.

[0064] According to the method for manufacturing radioactive isotopes according to embodiments of the present invention, by employing the aforementioned target system 100, direct bombardment of the target 30 by a beam can be achieved in a high-vacuum, window-free environment. This effectively reduces beam energy loss, improves beam utilization, and lowers system maintenance costs, while ensuring the stability and repeatability of isotope yield. Simultaneously, a cooling device 40 is activated during irradiation to ensure the target 30 maintains structural stability under thermal load, preventing target material performance degradation or radioactive product loss due to overheating, further ensuring the stability and repeatability of isotope yield.

[0065] In some embodiments of the present invention, in the step of introducing the accelerator beam into the target chamber 10 and bombarding the target 30, the emitted beam of the accelerator is an alpha particle beam, and the target material of the target 30 is bismuth, in order to prepare... 211 At.

[0066] In the above technical solution, by bombarding a bismuth target with an alpha particle beam, it is possible to prepare materials with medical value. 211 At, to meet the needs of clinical diagnosis and treatment, and improve the reliability of methods for manufacturing radioisotopes.

[0067] In some embodiments of the present invention, prior to the step of docking the beam inlet of the target chamber 10 with the outlet of the accelerator, the method further includes: installing the target body 30 into the target chamber 10 by means of a disassembly mechanism 50.

[0068] In some embodiments of the present invention, after the irradiation ends and the on / off control element 20 and vacuum interface 101 are turned off, the method further includes: disassembling the target 30 by means of disassembly mechanism 50 and moving it to the transmission interface 131, and transporting the target 30 as a whole to the hot chamber for subsequent processing by means of pneumatic transmission system.

[0069] The following is combined with Figures 1 to 11 This describes a specific embodiment of the target system 100 of the present invention.

[0070] The target system 100 includes: a target chamber 10, an on / off control component 20, a target body 30, a cooling device 40, and a disassembly mechanism 50.

[0071] The target chamber 10 includes a first part 11, a second part 12, and a third part 13 connected in sequence. The end of the first part 11 furthest from the second part 12 forms a beam inlet 10a. A vacuum port 101 is located on the second part 12. The target 30 and a cooling device 40 are located on the mounting port 10b of the third part 13. The interior of the third part 13 has a first region 13a and a second region 13b. The end of the third part 13 furthest from the second part 12 has a transmission port 131, which connects to the second region 13b. The target 30 is located within the first region 13a.

[0072] The on / off control element 20 is provided on the first part 11 for opening or closing the beam inlet 10a.

[0073] The target body 30 seals the connection between the third part 13 and the second part 12, and is arranged alongside the transmission interface 131 in the parallel direction of the first region 13a and the second region 13b. The target body 30 includes a target plate 31, a support frame 32, and a transmission shuttle 33. The end of the transmission shuttle 33 facing the beam inlet 10a is open. The support frame 32 is disposed within the transmission shuttle 33. The support frame 32 has a groove 32a with a bottom surface 32b, which is parallel to the target plate 31. The bottom surface 32b has an inlet 32c and an outlet 32d for conveying the cooling medium. The front side of the target plate 31 has a target material layer 311, and the back side of the target plate 31 has a cooling channel 312. The target plate 31 is disposed within the groove 32a, and a gap is formed between the back side of the target plate 31 and the bottom surface 32b. The cooling channel 312 communicates with the cooling device 40. The included angle between the axes of the target plate 31 and the transmission shuttle 33 is 10°.

[0074] The cooling device 40 has an inlet channel 40a and an outlet channel 40b for conveying the cooling medium. The inlet channel 40a is connected to the inlet 32c, and the outlet channel 40b is connected to the outlet 32d. The temperature of the cooling medium at the inlet 32c is 5°C, and the flow rate is 4 L / min.

[0075] The disassembly mechanism 50 includes a first drive member 51 and a second drive member 52. Both the first drive member 51 and the second drive member 52 are cylinders. The transmission interface 131 and the first drive member 51 are located on the same side of the target chamber 10. The first drive member 51 drives the connected cooling device 40 to engage or disengage the cooling device 40 from the support frame 32 along the axial direction of the transmission shuttle 33. The second drive member 52 drives the connected transmission shuttle 33 to move along an axial direction perpendicular to the transmission shuttle 33, causing the target 30 to move from the first region 13a to the second region 13b.

[0076] In the description of this specification, references to terms such as "some embodiments," "optionally," "furthermore," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0077] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A target system, characterized in that, Used for preparation 211 At, including: The target chamber is equipped with a beam inlet and a vacuum port; An on / off control element is disposed on the target chamber and is used to open or close the beam inlet. A target body, wherein the target body is disposed within the target chamber; A cooling device, which is connected to the target body, is used to exchange heat with the target body; The target body includes a target sheet, a support frame, and a transfer shuttle. The end of the transfer shuttle facing the beam inlet is open. The support frame is located inside the transfer shuttle. The target sheet is located on the support frame. The front side of the target sheet has a target material layer, and the back side of the target sheet has a cooling channel. The cooling channel is connected to the cooling device. The target sheet is inclined relative to the axis of the transfer shuttle so that the target material layer corresponds to the beam inlet.

2. The target system according to claim 1, characterized in that, The target chamber includes a first part, a second part, and a third part connected in sequence. The end of the first part away from the second part forms the beam inlet. The on / off control element is located on the first part. The vacuum interface is located on the second part. The target body and the cooling device are located on the third part. The target body seals the connection between the third part and the second part.

3. The target system according to claim 2, characterized in that, The third part has a first region and a second region inside. The end of the third part away from the second part is provided with a transmission interface, which is connected to the second region. The target is located in the first region. The target and the transmission interface are arranged in a parallel direction along the first region and the second region. The target system includes a disassembly mechanism, which drives the target to move from the first region to the second region.

4. The target system according to claim 1, characterized in that, The included angle between the axis of the target and the axis of the transmission shuttle is 5° to 45°.

5. The target system according to claim 1, characterized in that, The target chamber is provided with an installation port, and the cooling device is installed in the installation port. The target system includes a disassembly mechanism, which includes a first driving member and a second driving member. The first driving member drives the cooling device to engage or disengage from the support frame along the axial direction of the transfer shuttle. The second driving member drives the transfer shuttle to move along the axial direction perpendicular to the transfer shuttle. The target chamber is provided with a transfer interface, and the transfer interface and the first driving member are located on the same side of the target chamber.

6. The target system according to claim 1 or 4, characterized in that, The support frame is provided with a groove, the groove has a bottom surface, the bottom surface of the groove is parallel to the target plate, the bottom surface of the groove is provided with an inlet and an outlet for conveying cooling medium, the target plate is disposed in the groove, a gap is formed between the back of the target plate and the bottom surface of the groove, the cooling device has an inlet channel and an outlet channel for conveying cooling medium, the inlet channel is connected to the inlet, and the outlet channel is connected to the outlet.

7. The target system according to claim 6, characterized in that, The temperature of the cooling medium at the inlet is less than or equal to 20°C, and the flow rate is greater than or equal to 2L / min.

8. A method for manufacturing a radioactive isotope, characterized in that, The radioisotope is prepared using the target system as described in any one of claims 1 to 7, the method comprising: Connect the beam inlet of the target chamber to the outlet of the accelerator; The on / off control element is kept in the off state, and the target chamber is evacuated through the vacuum port to make the vacuum level inside the target chamber consistent with the vacuum level inside the accelerator's vacuum chamber; Open the on / off control device to connect the target chamber with the vacuum chamber of the accelerator; The beam from the accelerator is introduced into the target chamber and bombards the target, and the cooling device is controlled to cool and reduce the temperature of the target. After irradiation, shut off the on / off control and the vacuum port.

9. The method for manufacturing a radioactive isotope according to claim 8, characterized in that, In the step of introducing the accelerator beam into the target chamber and bombarding the target, the emitted beam of the accelerator is an alpha particle beam, and the target material of the target is bismuth, in order to prepare... 211 At.

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