Neutron capture therapy system

Abstract

The present invention provides a neutron capture therapy system, comprising a neutron generator and a beam shaper, the neutron capture therapy system further comprising a concrete wall that accommodates the neutron generator and the beam shaper and shields the radiation generated by the neutron generator and the beam shaper, the concrete wall and a reinforcement portion at least partially disposed in the concrete wall are used to support the beam shaper, the material elastic modulus of the reinforcement portion is not less than 40GPa, the yield strength is not less than 200MPa, and the ultimate strength is not less than 100MPa. In the neutron capture therapy system of the present invention, the reinforcement portion can increase the rigidity of the concrete, improve the tensile strength, and improve the bearing capacity.

Description

Technical Field

[0001] The invention relates to a radiation irradiation system, in particular to a neutron capture therapy system. Background Art

[0002] With the development of atomic science, radiation therapy such as cobalt-60, linear accelerator, and electron beam has become one of the main means of cancer treatment. However, traditional photon or electron therapy is limited by the physical conditions of radiation itself. While killing tumor cells, it will also cause damage to a large number of normal tissues along the beam path. In addition, due to the different sensitivity of tumor cells to radiation, traditional radiotherapy is often not effective in treating malignant tumors that are more resistant to radiation (such as glioblastoma multiforme and melanoma).

[0003] In order to reduce radiation damage to normal tissues around tumors, the concept of targeted therapy in chemotherapy has been applied to radiotherapy; and for tumor cells with high radiation resistance, radiation sources with high relative biological effectiveness (RBE) are currently being actively developed, such as proton therapy, heavy particle therapy, neutron capture therapy, etc. Among them, neutron capture therapy is a combination of the above two concepts, such as boron neutron capture therapy, which provides a better cancer treatment option than traditional radiation by specifically aggregating boron-containing drugs in tumor cells and coordinating precise neutron beam control.

[0004] Various radiations are generated during radiotherapy, such as low-energy to high-energy neutrons and photons generated during boron neutron capture therapy. These radiations may cause varying degrees of damage to normal human tissues. Therefore, in the field of radiotherapy, how to achieve effective treatment while reducing radiation contamination to the external environment, medical staff or normal tissues of the irradiated body is an extremely important issue. Radiotherapy equipment is usually placed in concrete buildings to isolate the radiation that may be generated by the equipment. In general reinforced concrete structures, after the steel bars are activated by neutrons, radioactive isotopes with longer half-lives are generated, such as the half-life of cobalt 60, which is 5.27 years, forming long-lived radioactive waste, which has a negative impact on the environment and radiation safety.

[0005] Therefore, it is necessary to propose a new technical solution to solve the above problems. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a neutron capture therapy system, including a neutron generating device and a beam shaping body, wherein the neutron generating device includes an accelerator and a target material, wherein the charged particle line generated by the accelerator interacts with the target material to generate a neutron line, wherein the beam shaping body includes a reflector, a retarder, a thermal neutron absorber, a radiation shielding body and a beam outlet, wherein the retarder decelerates the neutrons generated from the target material to the epithermal neutron energy zone, wherein the reflector surrounds the retarder and guides the deviated neutrons back to the retarder to improve the epithermal neutron beam intensity, and wherein the thermal neutron absorber is used to The radiation shielding body is arranged around the beam outlet at the rear of the reflector to shield the leaked neutrons and photons to reduce the normal tissue dose in the non-irradiated area. The neutron capture therapy system also includes a concrete wall for accommodating the neutron generating device and the beam shaping body. The concrete wall and the reinforcement part at least partially arranged in the concrete wall are used to support the beam shaping body. The elastic modulus of the material of the reinforcement part is not less than 40GPa, the yield strength is not less than 200MPa, and the ultimate strength is not less than 100MPa. The concrete structure can shield the neutrons and other radiation lines leaked during the operation of the neutron capture therapy system. The reinforcement part can increase the rigidity of the concrete, improve the tensile strength, and improve the bearing capacity.

[0007] Furthermore, more than 90% (by weight) of the material of the reinforcement part is composed of at least one element of C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, and Ca. The material of the reinforcement part is composed of elements with a small cross-section for interaction with neutrons or a short half-life of radioactive isotopes produced after neutron activation. Since the radioactivity derived from neutron activation is small, in addition to reasonably suppressing the dose caused by secondary radiation, it is more conducive to future equipment dismantling.

[0008] Furthermore, the half-life of the radioactive isotope generated by the reinforcement portion after being activated by neutrons is less than 1 year.

[0009] Furthermore, the material of the reinforcement part is at least partially aluminum alloy or carbon fiber composite material or glass fiber composite material. Aluminum has a short half-life after neutron activation, and carbon fiber composite material or glass fiber composite material has good anti-activation performance. Compared with traditional reinforced concrete structures, the radioactivity derived from neutron activation in a limited time is greatly reduced.

[0010] Furthermore, the neutron capture therapy system further comprises a treatment table and a collimator, wherein the collimator is arranged at the rear of the beam outlet to converge the neutron beam, and the neutron beam generated by the neutron generating device is irradiated to the irradiated body on the treatment table through the beam shaping body and the collimator, and a radiation shielding device is arranged between the irradiated body and the beam outlet to shield the radiation of the beam from the beam outlet to the normal tissue of the irradiated body. There can be one or more targets, and the charged particle beam can selectively act on one or more targets or on multiple targets at the same time to generate one or more neutron beams for treatment. Corresponding to the number of targets, there can also be one or more beam shaping bodies, collimators, and treatment tables.

[0011] Furthermore, the neutron capture therapy system further includes a charged particle beam generating chamber and an irradiation chamber, the irradiated body on the treatment table is treated with neutron beam irradiation in the irradiation chamber, the charged particle beam generating chamber accommodates the accelerator, the concrete wall includes a partition wall between the charged particle beam generating chamber and the irradiation chamber, and the beam shaping body is supported on a reinforcement portion at least partially disposed within the partition wall. The partition wall may completely separate the irradiation chamber from the charged particle beam generating chamber; or it may be a partial partition between the irradiation chamber and the charged particle beam generating chamber, and the irradiation chamber and the charged particle beam generating chamber are interconnected. Multiple treatment tables may be disposed in the same irradiation chamber, or a separate irradiation chamber may be disposed for each treatment table.

[0012] Furthermore, the neutron generating device further comprises a beam transmission part, which transmits the charged particle beam generated by the accelerator to the target material. A through hole is provided on the partition wall, and the beam transmission part passes through the through hole.

[0013] Another aspect of the present invention provides a support device for supporting a beam shaping body, wherein the beam shaping body is used to adjust the beam quality of the neutron line generated by the neutron generating device, wherein the support device comprises a housing cavity, wherein the beam shaping body is installed in the housing cavity, and wherein the support device further comprises a concrete wall and a reinforcement portion at least partially disposed in the concrete wall. The concrete structure can shield neutrons and other radiation lines leaked during operation, while the beam shaping body is very sensitive to deformation, requiring the support structure to have sufficient rigidity, and the reinforcement portion disposed in the concrete can increase the rigidity of the concrete, improve the tensile strength, and improve the bearing capacity.

[0014] Furthermore, the elastic modulus of the material of the reinforcement portion is not less than 40 GPa, the yield strength is not less than 200 MPa, and the ultimate strength is not less than 100 MPa.

[0015] Furthermore, more than 90% (by weight) of the material of the reinforcement part is composed of at least one element selected from C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, and Ca. The material of the reinforcement part is composed of elements with a small cross section for interaction with neutrons or a short half-life of radioactive isotopes produced after neutron activation. Since the radioactivity derived from neutron activation is small, in addition to reasonably suppressing the dose caused by secondary radiation, it is more conducive to future equipment dismantling.

[0016] Furthermore, the half-life of the radioactive isotope generated by the neutron activation of the reinforcement portion is less than 1 year.

[0017] Further, the reinforcement part includes a first reinforcement part and a second reinforcement part, the first reinforcement part is arranged in the concrete wall, and the second reinforcement part at least partially protrudes from the concrete wall.

[0018] Further, the first reinforcement part includes a ring, a frame and distribution ribs, the ring is arranged around the beam shaping body, the frame is arranged around the ring, the distribution ribs are distributed in the concrete at a predetermined spacing in the horizontal direction and the thickness direction of the concrete, the distribution ribs at least partially pass through the frame or overlap with the frame, the distribution ribs at least partially overlap with the ring, the ring and the frame are made of aluminum alloy or carbon fiber composite material or glass fiber composite material, and the distribution ribs are made of steel or aluminum alloy or carbon fiber composite material or glass fiber composite material. The ring and the frame increase the rigidity of the concrete and improve the tensile strength, and the distribution ribs can prevent the concrete from cracking and improve the overall performance of the wall.

[0019] As a preferred embodiment, the aluminum alloy is an aluminum-magnesium alloy, the carbon fiber composite material is a carbon fiber resin composite material, the glass fiber composite material is a glass fiber resin composite material, the ring is a profile or a rib structure, the frame is composed of a horizontal frame profile beam or a horizontal skeleton and a vertical frame profile column, the horizontal frame profile beam and the vertical frame profile column are bolted or welded, and the horizontal skeleton includes horizontal longitudinal bars and stirrups. Concrete has high compressive strength, but low tensile strength, and its strain increases slowly over time under constant stress, while the aluminum-magnesium alloy profile has good tensile strength and shear strength, high rigidity, and does not increase strain over time under constant stress, aluminum-magnesium alloy ribs have good tensile bearing capacity, and carbon fiber resin composite materials or glass fiber resin composite materials have high tensile strength, which can make up for the deficiencies in the mechanical properties and material properties of concrete, and stirrups can improve the shear resistance of the wall.

[0020] Further, the second reinforcement portion includes a horizontal support plate and a side plate connecting the support plate and the first reinforcement portion, and the accommodating cavity is formed on the support plate.

[0021] Furthermore, a flange is provided on one side of the support plate facing the first reinforcement portion, the flange forms the accommodating cavity and limits the beam shaping body in the horizontal direction, and a through hole is formed on the support plate, and the neutron line passes through the beam shaping body and comes out of the through hole.

[0022] In another aspect, the present invention provides a building for a neutron irradiation system, wherein the building is a concrete structure for accommodating the neutron irradiation system, and a reinforcement part is arranged in the concrete structure, wherein more than 90% (by weight) of the material of the reinforcement part is composed of at least one element selected from C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, and Ca. The concrete structure can shield neutrons and other radiations leaked during the operation of the neutron irradiation system, and the reinforcement part can increase the rigidity of the concrete, improve the tensile strength, and increase the bearing capacity. The material of the reinforcement part is composed of elements with a small cross-section for interaction with neutrons or a short half-life of radioactive isotopes produced after being activated by neutrons, and the radioactivity derived from neutron activation is small, which not only reasonably suppresses the dose caused by secondary radiation, but also facilitates the future removal of equipment.

[0023] Furthermore, the reinforcement part includes horizontal and / or vertical distribution bars, which are distributed in the concrete structure at predetermined intervals in the horizontal, vertical and thickness directions of the concrete structure. The distribution bars can prevent concrete cracking and improve the overall performance of the wall.

[0024] Furthermore, the elastic modulus of the material of the reinforcement portion is not less than 40 GPa, the yield strength is not less than 200 MPa, and the ultimate strength is not less than 100 MPa.

[0025] Furthermore, the half-life of the radioactive isotope generated by the reinforcement portion after being activated by neutrons is less than 1 year.

[0026] Furthermore, the material of the reinforcement part is at least partially aluminum alloy or carbon fiber composite material or glass fiber composite material. Aluminum has a short half-life after neutron activation, and carbon fiber composite material or glass fiber composite material has good anti-activation performance. Compared with traditional reinforced concrete structures, the radioactivity derived from neutron activation in a limited time is greatly reduced.

[0027] Furthermore, the aluminum alloy is an aluminum-magnesium alloy, the carbon fiber composite material is a carbon fiber resin composite material, the glass fiber composite material is a glass fiber resin composite material, and the concrete of the concrete structure is boron-containing barite concrete. Aluminum-magnesium alloy, carbon fiber composite material or glass fiber composite material has excellent mechanical properties, and boron-containing concrete has better neutron absorption performance. In addition to enhancing the radiation shielding effect of concrete, it can also reduce the neutron exposure of metal materials in concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a schematic structural diagram of a neutron capture therapy system in an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of the supporting structure of a beam shaping body of a neutron capture therapy system according to a first embodiment of the present invention;

[0030] Figure 3 for Figure 2 Schematic diagram at section AA;

[0031] Figure 4 for Figure 2 Schematic diagram of the section at BB;

[0032] Figure 5 for Figure 2 Schematic diagram of the CC section;

[0033] Figure 6 A schematic diagram of a support structure of a beam shaping body of a neutron capture therapy system according to a second embodiment of the present invention;

[0034] Figure 7 for Figure 6 Schematic diagram of the DD section;

[0035] Figure 8 for Figure 6 Schematic diagram of the EE section;

[0036] Fig. 9 for Figure 6 Schematic diagram of the FF section;

[0037] Fig.10 A schematic diagram of the support structure of a beam shaping body of a neutron capture therapy system according to a third embodiment of the present invention;

[0038] Fig.11 for Fig.10 Schematic diagram of the GG section. DETAILED DESCRIPTION

[0039] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0040] like Figure 1The neutron irradiation system in this embodiment is preferably a boron neutron capture therapy system 100, including a neutron generator 10, a beam shaper 20, a collimator 30 and a treatment table 40. The neutron generator 10 includes an accelerator 11 and a target material T. The accelerator 11 accelerates charged particles (such as protons, deuterons, etc.) to generate charged particle lines P such as proton lines. The charged particle lines P irradiate the target material T and react with the target material T to generate neutron lines (neutron beams) N. The target material T is preferably a metal target material. The appropriate nuclear reaction is selected based on the required neutron yield and energy, the energy and current of the accelerated charged particles that can be provided, the physical and chemical properties of the metal target material, and other characteristics. The commonly discussed nuclear reactions are 7Li(p,n)7Be and 9Be(p,n)9B, both of which are endothermic reactions. The energy thresholds of the two nuclear reactions are 1.881MeV and 2.055MeV, respectively. Since the ideal neutron source for boron neutron capture therapy is an epithermal neutron of the keV energy level, theoretically, if protons with energy only slightly higher than the threshold are used to bombard the metal lithium target, relatively low-energy neutrons can be produced, which can be used clinically without too much slowing down treatment. However, the cross-sections of the two targets of lithium metal (Li) and beryllium metal (Be) with protons of the threshold energy are not high. In order to produce a sufficiently large neutron flux, higher energy protons are usually selected to induce nuclear reactions. The ideal target should have a high neutron yield, the generated neutron energy distribution is close to the epithermal neutron energy region (described in detail below), there is not much strong penetrating radiation generated, it is safe, cheap, easy to operate, and resistant to high temperatures, but in fact, it is impossible to find a nuclear reaction that meets all the requirements. In the embodiment of the present invention, a target made of lithium metal is used. However, it is well known to those skilled in the art that the material of the target material T can also be made of metal materials other than lithium and beryllium, such as tantalum (Ta) or tungsten (W); the target material T can be in the shape of a disk, or other solid shapes, or a liquid (liquid metal). The accelerator 11 can be a linear accelerator, a cyclotron, a synchrotron, or a synchrocyclotron, and the neutron generating device 10 can also be a nuclear reactor instead of an accelerator and a target material. Regardless of whether the neutron source of the boron neutron capture therapy comes from a nuclear reactor or a nuclear reaction between charged particles in the accelerator and the target material, what is actually produced is a mixed radiation field, that is, the beam contains neutrons and photons ranging from low energy to high energy. For boron neutron capture therapy of deep tumors, in addition to epithermal neutrons, the more the rest of the radiation content, the greater the proportion of non-selective dose deposition in normal tissues, so these radiations that will cause unnecessary doses should be reduced as much as possible. In addition, for the normal tissues of the irradiated body, various radiations should be avoided from being excessive, which also causes unnecessary dose deposition.

[0041] The neutron beam N generated by the neutron generating device 10 is sequentially irradiated to the irradiated body 200 on the treatment table 40 through the beam shaping body 20 and the collimator 30. The beam shaping body 20 can adjust the beam quality of the neutron beam N generated by the neutron generating device 10. The collimator 30 is used to converge the neutron beam N so that the neutron beam N has a higher targeting in the treatment process. By adjusting the collimator 30, the direction of the beam and the positional relationship between the beam and the irradiated body 200 on the treatment table 40 can be adjusted. The positions of the treatment table 40 and the irradiated body 200 can also be adjusted so that the beam is aimed at the tumor cells M in the irradiated body 200. These adjustments can be manually operated or automatically realized through a series of control mechanisms. It can be understood that the present invention may not have a collimator, and the beam directly irradiates the irradiated body 200 on the treatment table 40 after coming out of the beam shaping body 20.

[0042] The beam shaping body 20 further includes a reflector 21, a retarder 22, a thermal neutron absorber 23, a radiation shield 24 and a beam outlet 25. Since the neutrons generated by the neutron generating device 10 have a wide energy spectrum, in addition to epithermal neutrons that meet the treatment needs, it is necessary to reduce the content of other types of neutrons and photons as much as possible to avoid causing harm to the operator or the irradiated body. Therefore, the neutrons coming out of the neutron generating device 10 need to pass through the retarder 22 to adjust the fast neutron energy (>40keV) to the epithermal neutron energy zone (0.5eV-40keV) and reduce the thermal neutrons (<0.5eV) as much as possible. The retarder 22 is made of a material with a large cross-section for fast neutrons and a small cross-section for epithermal neutrons. As a preferred embodiment, the retarder 13 is made of at least one of D2O, AlF3, Fluental, CaF2, Li2CO3, MgF2 and Al2O3; the reflector 21 surrounds the retarder 22 and adjusts the energy of the fast neutrons (>40keV) therein to the epithermal neutron energy zone (0.5eV-40keV) and reduce the thermal neutrons (<0.5eV) as much as possible. The retarder 22 is made of a material with a large cross-section for fast neutrons and a small cross-section for epithermal neutrons. As a preferred embodiment, the retarder 13 is made of at least one of D2O, AlF3, Fluental, CaF2, Li2CO3, MgF2 and Al2O3; the reflector 21 surrounds the retarder 22 and 22 reflects the neutrons diffused to the surroundings back to the neutron beam N to improve the utilization rate of the neutrons, and is made of a material with strong neutron reflection ability. As a preferred embodiment, the reflector 21 is made of at least one of Pb or Ni; a thermal neutron absorber 23 is provided at the rear of the retarder 22, which is made of a material with a large cross-section for interacting with thermal neutrons. As a preferred embodiment, the thermal neutron absorber 23 is made of Li-6. The thermal neutron absorber 23 is used to absorb thermal neutrons passing through the retarder 22 to reduce the content of thermal neutrons in the neutron beam N and avoid excessive dose to shallow normal tissues during treatment; a radiation shielding body 24 is arranged at the rear of the reflector around the beam outlet 25, and is used to shield neutrons and photons leaking from the part other than the beam outlet 25. The material of the radiation shielding body 24 includes at least one of a photon shielding material and a neutron shielding material. As a preferred embodiment, the material of the radiation shielding body 24 includes a photon shielding material lead (Pb) and a neutron shielding material polyethylene (PE). The collimator 30 is disposed at the rear of the beam outlet 25. The epithermal neutron beam from the collimator 30 irradiates the irradiated body 200, and is slowed down to thermal neutrons after passing through the shallow normal tissue to reach the tumor cells M. It can be understood that the beam shaping body 20 can also have other structures as long as the epithermal neutron beam required for treatment can be obtained.

[0043] After the irradiated body 200 takes or is injected with a boron-containing (B-10) drug, the boron-containing drug selectively accumulates in the tumor cells M. Then, the boron-containing (B-10) drug has a high capture cross section for thermal neutrons, and two heavily charged particles, 4He and 7Li, are generated by 10B(n,α)7Li neutron capture and nuclear fission reactions. The average energy of the two charged particles is about 2.33MeV, and they have high linear energy transfer (LET) and short range characteristics. The linear energy transfer and range of the α short particle are 150keV / μm and 8μm, respectively, while the 7Li heavy-charged particle is 175keV / μm and 5μm. The total range of the two particles is approximately equivalent to the size of a cell. Therefore, the radiation damage caused to the organism can be limited to the cellular level, so that the purpose of locally killing tumor cells can be achieved without causing too much damage to normal tissues.

[0044] In this embodiment, a radiation shielding device 50 is further provided between the irradiated body 200 and the beam outlet 25 to shield the radiation of the beam from the beam outlet 25 to the normal tissue of the irradiated body. It is understandable that the radiation shielding device 50 may not be provided.

[0045] The boron neutron capture therapy system 100 is contained in a building of concrete structure as a whole. Specifically, the boron neutron capture therapy system 100 further includes an irradiation chamber 101 and a charged particle beam generation chamber 102. The irradiated object 200 on the treatment table 40 is irradiated with a neutron beam N in the irradiation chamber 101. The charged particle beam generation chamber 102 contains an accelerator 11. The beam shaping body 20 is supported by a partition wall 103 between the irradiation chamber 101 and the charged particle beam generation chamber 102. It can be understood that the partition wall 103 can be a partition that completely separates the irradiation chamber 101 and the charged particle beam generation chamber 102; or it can be a partial partition between the irradiation chamber 101 and the charged particle beam generation chamber 102, and the irradiation chamber 101 and the charged particle beam generation chamber 102 are connected. There can be one or more targets T, and the charged particle line P can selectively act on one or more targets T or on multiple targets T at the same time to generate one or more neutron beams N for treatment. According to the number of the targets T, there may be one or more beam shapers 20, collimators 30, and treatment tables 40; multiple treatment tables may be arranged in the same irradiation room, or a separate irradiation room may be arranged for each treatment table.

[0046] The irradiation chamber 101 and the charged particle beam generation chamber 102 are spaces surrounded by a concrete wall W (including a partition wall 103). The concrete structure can shield neutrons and other radiation leaked during the operation of the boron neutron capture therapy system 100. The concrete wall W includes a reinforcement part (described in detail below) at least partially arranged in the concrete to increase rigidity, improve tensile strength, and improve bearing capacity. The elastic modulus of the material of the reinforcement part is not less than 40GPa, the yield strength is not less than 200MPa, and the ultimate strength is not less than 100MPa; at the same time, the material of the reinforcement part is composed of elements with a small cross-section for interaction with neutrons or a short half-life (less than 1 year) of radioactive isotopes generated after being activated by neutrons. Specifically, more than 90% (by weight) of the material of the reinforcement part is composed of at least one of C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, and Ca. In this embodiment, the material of the reinforcement part is at least partially aluminum alloy, carbon fiber composite material, glass fiber composite material, or a combination thereof. When aluminum alloy is selected, it can be at least partially aluminum-magnesium alloy. Aluminum has a short half-life of only 2.2 minutes after being activated by neutrons. In traditional reinforced concrete structures, the iron, cobalt, nickel and other elements rich in steel bars have a long half-life after being activated by neutrons, such as the half-life of cobalt 60 is 5.27 years. The use of aluminum-magnesium alloy can greatly reduce the radioactivity derived from neutron activation within a limited time. In addition to reasonably suppressing the dose caused by secondary radiation, it is more conducive to the future removal of equipment. Aluminum-magnesium alloy has excellent mechanical properties. It is understandable that other aluminum alloys can also be selected. When carbon fiber composite materials or glass fiber composite materials are selected, it can be a composite material of carbon fiber or glass fiber and resin. The composite material of carbon fiber or glass fiber and resin has high strength and good anti-activation performance. It is understandable that other composite materials can also be selected. Below, the concrete structure of the partition wall 103 is introduced in detail. The beam shaping body 20 is supported by the partition wall 103 and the reinforcement part at least partially arranged in the partition wall 103.

[0047] Continue reading Figure 2-Figure 5, is a first embodiment of the partition wall 103, the partition wall 103 is a side wall, that is, the irradiation chamber 101 and the charged particle beam generation chamber 102 are arranged horizontally, and a receiving cavity 1031 is provided on the partition wall 103, and the beam shaping body 20 is installed in the receiving cavity 1031. The receiving cavity 1031 is through in the thickness direction of the partition wall 103. In this embodiment, the beam shaping body 20 is cylindrical as a whole, and the receiving cavity 1031 is a circular through hole. Since the beam shaping body is very sensitive to deformation, the supporting structure is required to have sufficient rigidity, and the partition wall 103 is provided with a reinforcement part 1032 in the concrete structure. The reinforcement part 1032 includes a circular ring bar a surrounding the beam shaping body 20 and a frame bar b surrounding the circular ring bar a. The frame bar b includes a horizontal frame b1 and a vertical frame b2. The horizontal frame b1 includes a horizontal longitudinal bar b11 and a stirrup b12. The vertical frame b2 includes a vertical longitudinal bar b21 and a stirrup b22. The number of horizontal / vertical longitudinal bars and stirrups is determined according to actual conditions. The reinforcement part 1032 also includes horizontal and vertical distribution bars c. The horizontal and vertical distribution bars c are distributed in the entire concrete wall at a predetermined spacing in the horizontal, vertical and concrete thickness directions. The spacing is determined according to specific conditions and is only schematically drawn in the figure. The horizontal and vertical distribution bars c pass through the frame bar b, and the horizontal and vertical distribution bars c intersecting with the circular ring bar a overlap with it to increase the anchoring performance and facilitate its positioning during construction; the ends of the horizontal longitudinal bars b11 and the vertical longitudinal bars b21 are provided with anchor plates d to enhance the bonding strength of the horizontal longitudinal bars b11 and the vertical longitudinal bars b21. In addition to the distribution reinforcement overlapped with the circular reinforcement, the distribution reinforcement can also be set only in the area outside the frame reinforcement. In this case, it is ensured that the distribution reinforcement and the frame reinforcement have a certain overlap length, and the anchor plate may not be set. The materials of the circular reinforcement a and the frame reinforcement b are aluminum-magnesium alloy or carbon fiber resin composite material or glass fiber resin composite material; the material of the distribution reinforcement is also aluminum-magnesium alloy or carbon fiber resin composite material or glass fiber resin composite material. Since neutrons are generated in the beam shaping body, the materials in the periphery are most seriously activated. It can be understood that the distribution reinforcement can also be at least partially (such as the part other than the frame reinforcement) as steel bars to reduce costs. At the same time, the number of distribution reinforcements can meet the requirements of the building structure to reduce the generation of radioactive nuclides. It is well known to those skilled in the art that during the construction process, the distribution reinforcement can also be provided with tension bars (not shown) in the direction of the concrete thickness, and the number of tension bars is determined according to the actual situation; the intersecting bars are tied and connected by fixings such as steel wires, such as horizontal and vertical distribution bars, horizontal / vertical distribution bars and tension bars, horizontal / vertical longitudinal bars and stirrups, and circular reinforcements and horizontal / vertical distribution bars. It can be understood that when the beam shaping body is not installed in other concrete walls W, only distribution bars can be installed. During construction, the distribution bars of other concrete walls are first tied and anchored together with the distribution bars, annular bars and frame bars of the partition wall 103, and then the template of the wall edge (including the inner wall of the receiving cavity) is set up to pour concrete. After the pouring is completed, the beam shaping body is installed in the receiving cavity of the partition wall.It is understandable that the construction process can also be carried out in other ways known to those skilled in the art. Concrete has good compressive bearing capacity, and aluminum-magnesium alloy bars and steel bars have good tensile bearing capacity. The configuration of aluminum-magnesium alloy bars and steel bars in the tensile parts can make up for the lack of tensile strength of concrete, and the configuration of stirrups can improve the shear resistance of the wall. Distributed steel bars can prevent concrete cracking and improve the overall performance of the wall.

[0048] like Figure 6-Figure 9, which is a second embodiment of the partition wall 103', and only the differences from the first embodiment are described below. The reinforcement part 1032' of the partition wall 103' includes a circular profile a' surrounding the beam shaping body and a frame profile b' surrounding the circular profile a', and the frame profile b' includes a horizontal frame profile beam b1' and a vertical frame profile column b2'. The reinforcement part 1032' also includes horizontal and vertical distribution bars c', which are distributed in the entire concrete wall at a predetermined spacing in the horizontal, vertical and concrete thickness directions, and the spacing is determined according to specific conditions. The horizontal frame profile beam b1' and the vertical frame profile column b2' are connected by bolts, or by welding, etc., as long as the connection strength of the joints is guaranteed; the horizontal and vertical distribution bars c' pass through the reserved holes of the aluminum-magnesium alloy frame profile b' to strengthen the anchoring performance and ductility of the wall, and the horizontal and vertical distribution bars c' that intersect with the circular profile a' overlap with it to increase the anchoring performance and facilitate its positioning during construction. In addition to the distribution bars that intersect with the circular profile, distribution bars can also be set only in the area outside the frame profile, and the distribution bars overlap with the frame profile. The materials of the circular profile a' and the frame profile b' are aluminum-magnesium alloy or carbon fiber resin composite material or glass fiber resin composite material; the material of the distribution ribs is also aluminum-magnesium alloy or carbon fiber resin composite material or glass fiber resin composite material. Since neutrons are generated in the beam shaping body, the materials around them are most seriously activated. It can be understood that the distribution ribs can also be at least partially (such as the part outside the frame profile) as steel bars to reduce costs. At the same time, the number of distribution ribs can meet the requirements of the building structure to reduce the generation of radioactive nuclides. It is well known to those skilled in the art that during the construction process, the distribution ribs can also be provided with tie bars (not shown) in the direction of the concrete thickness, and the number of tie bars is determined according to the actual situation; the intersecting ribs are tied and connected by fixings such as steel wires, such as horizontal and vertical distribution ribs, horizontal / vertical distribution ribs and tie bars, and circular profiles and horizontal / vertical distribution ribs. In this embodiment, the cross-sectional shape of the aluminum-magnesium alloy profile is H-shaped. It can be understood that the cross-sectional shape can also be other shapes. During construction, first tie and anchor the distribution bars of other concrete walls together with the distribution bars, circular ring profiles, frame profiles, etc. of the partition wall 103', then set up the template of the wall edge (including the inner wall of the accommodating cavity) to pour the concrete, and after the pouring is completed, install the beam shaping body in the accommodating cavity of the partition wall. It can be understood that the construction process can also be carried out in other ways familiar to those skilled in the art. Concrete has high compressive strength, but low tensile strength, and its strain increases slowly over time under constant stress. The aluminum-magnesium alloy profile has good tensile strength and shear strength, high rigidity, and its strain does not increase over time under constant stress, which can make up for the deficiencies in the mechanical properties and material properties of concrete. Distributed steel bars can prevent concrete cracking and improve the overall performance of the wall.

[0049] It can be understood that the reinforcement part of the partition wall can also be a combination of the above two embodiments, such as the reinforcement part can include annular ribs surrounding the beam shaping body and a frame profile surrounding the annular ribs, or annular profile surrounding the beam shaping body and a frame rib surrounding the annular profile.

[0050] like Figure 10-11 , which is a third embodiment of the partition wall 103''. In this embodiment, the irradiation chamber and the charged particle beam generating chamber are arranged vertically, that is, the partition wall 103'' is a floor (floor or ceiling). The neutron generating device 10'' also includes a beam transmission part 12'', which transmits the charged particle line generated by the accelerator 11'' to the target material. A through hole 1031'' is set on the partition wall 103'', and the beam transmission part 12'' passes through the through hole 1031''. The reinforcement part 1032'' of the partition wall 103'' includes a first reinforcement part d and a second reinforcement part e, the first reinforcement part d is arranged in the concrete of the partition wall 103'', the second reinforcement part e at least partially extends out of the concrete of the partition wall 103'', the second reinforcement part e includes a horizontal support plate e1 and a side plate e2 connecting the support plate e1 and the first reinforcement part d, and the beam shaping body 20'' is supported on the horizontal support plate e1. In this embodiment, the second reinforcement part e is a U-shaped groove structure, and the side plates e2 are two opposite side plates, and the material is aluminum-magnesium alloy or carbon fiber resin composite material or glass fiber resin composite material to reduce the generation of radioactive nuclides; considering that the structural steel has high strength, good plastic toughness, uniform material and good weldability, steel can also be used; it can be understood that other materials or other forms of structures can also be used. A flange e11 is provided on one side of the support plate e1 facing the first reinforcement portion d, and the beam shaping body 20'' is located inside the flange e11, and the flange e11 limits the beam shaping body 20'' in the horizontal direction. In this embodiment, the beam shaping body is cylindrical as a whole, and the flange is a circular reinforcing rib correspondingly. A through hole e12 is also formed on the support plate e1, and the neutron beam N generated by the neutron generating device 10 passes through the beam shaping body 20'' and comes out from the through hole e12. In this embodiment, the through hole e12 is formed by cutting on the support plate e1.

[0051] On the one hand, the first reinforcement part strengthens the strength of the edge of the floor opening (through hole), and on the other hand, provides support for the beam shaping body. The first reinforcement part can be constructed according to the reinforcement part in the above embodiment to include frame ribs / profiles and circular ribs / profiles. Since this is a floor, the frame ribs or frame profiles only include horizontal skeletons or horizontal frame profile beams, and the vertical skeleton or vertical frame profile columns are replaced by horizontal skeletons or horizontal frame profile beams. The specific structure is not described in detail here, and only two profile beams are illustrated in the figure. When the first reinforcement part is constructed as a frame profile, the side plate e2 is welded or bolted to the frame profile. It can be understood that other connection methods can also be used as long as the connection strength is guaranteed; when the first reinforcement part is constructed as a frame rib, an anchor plate is set at the end of the side plate e2 to anchor it with the frame ribs. Considering the vertical force of the floor and the first reinforcement part, the horizontal skeleton or horizontal frame profile beam connected to the side plate extends over the entire length of the floor. The reinforcement part 1032'' also includes (horizontal) distribution bars c'', tension bars (not shown), etc., as in the above-mentioned embodiment. The distribution bars c'' are distributed in the concrete at a predetermined interval in the horizontal direction and the thickness direction of the concrete. During construction, the distribution bars of other concrete walls are first tied and anchored together with the distribution bars, frame bars / profiles, and circular ring bars / profiles of the partition wall 103'', and the second reinforcement part is welded or anchored to the first reinforcement part. Then, a template of the wall edge (including the inner wall of the through hole) is set up to cast concrete. After the casting is completed, the beam shaping body is installed into the flange from the side of the second reinforcement part without the side plate, and the beam transmission part is installed through the through hole. It can be understood that the construction process can also be carried out in other ways well known to those skilled in the art.

[0052] The boron neutron capture therapy system 100 may also include a preparation room, a control room and other spaces for auxiliary treatment. Each irradiation room may be equipped with a preparation room for preparatory work such as fixing the irradiated body to the treatment table, injecting boron medicine, and simulating the treatment plan before irradiation treatment. A connecting channel is set between the preparation room and the irradiation room. After the preparation work is completed, the irradiated body is directly pushed into the irradiation room or automatically entered into the irradiation room by the control mechanism through the track. The control room is used to control the accelerator, beam transmission unit, treatment table, etc., to control and manage the entire irradiation process. The management personnel can also monitor multiple irradiation rooms at the same time in the control room.

[0053] The concrete wall in this embodiment is made of boron-containing barite concrete with a thickness of more than 1m and a density of 3g / cc. Boron-containing concrete has better neutron absorption performance. In addition to enhancing the radiation shielding effect of concrete, it can also reduce the neutron exposure of metal materials in concrete. It can be understood that it can also have other thicknesses or densities or be replaced with other materials, and the thickness, density or material of the concrete wall in different parts can also be different. It can be understood that the present invention can also be applied to other types of neutron irradiation systems.

[0054] Although the above describes an illustrative specific embodiment of the present invention to facilitate those skilled in the art to understand the present invention, it should be clear that the present invention is not limited to the scope of the specific embodiment. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious and are all within the scope of protection required by the present invention.

Claims

1. A neutron capture therapy system, characterized in that: The invention comprises a neutron generating device and a beam shaping body, wherein the neutron generating device comprises an accelerator and a target material, wherein the charged particle line generated by the accelerator interacts with the target material to generate a neutron line, wherein the beam shaping body comprises a reflector, a retarder, a thermal neutron absorber, a radiation shielding body and a beam outlet, wherein the retarder decelerates the neutrons generated from the target material to the epithermal neutron energy zone, wherein the reflector surrounds the retarder and guides the deviated neutrons back to the retarder to improve the epithermal neutron beam intensity, wherein the thermal neutron absorber is used to absorb thermal neutrons to avoid excessive doses to shallow normal tissues during treatment, and wherein the radiation shielding body is arranged around the beam outlet and disposed at the The rear part of the reflector is used to shield leaked neutrons and photons to reduce the normal tissue dose in the non-irradiated area. The neutron capture therapy system also includes a concrete wall that accommodates the neutron generation device and the beam shaping body. The concrete wall and a reinforcement part at least partially arranged in the concrete wall are used to support the beam shaping body. The reinforcement part includes a first reinforcement part and a second reinforcement part. The first reinforcement part is arranged in the concrete wall, and the second reinforcement part at least partially extends out of the concrete wall. The second reinforcement part includes a horizontal support plate and a side plate connecting the horizontal support plate and the first reinforcement part. The beam shaping body is supported on the horizontal support plate.

2. The neutron capture therapy system according to claim 1, characterized in that: A flange is provided on a side of the horizontal support plate facing the first reinforcing portion, the beam shaping body is located inside the flange, and the flange limits the beam shaping body in a horizontal direction.

3. The neutron capture therapy system according to claim 2, characterized in that: The beam shaping body is cylindrical as a whole, and the flange is a circular reinforcing rib.

4. The neutron capture therapy system according to claim 1, characterized in that: The horizontal support plate is provided with a through hole, and the neutron beam generated by the neutron generating device passes through the beam shaping body and is emitted from the through hole.

5. The neutron capture therapy system according to claim 1, characterized in that: The neutron generating device further includes a beam transmitting portion, which transmits the charged particle beam generated by the accelerator to the target material. The concrete wall is provided with a through hole, and the beam transmitting portion passes through the through hole.

6. The neutron capture therapy system according to claim 1, characterized in that: The elastic modulus of the material of the reinforcement part is not less than 40 GPa, the yield strength is not less than 200 MPa, and the ultimate strength is not less than 100 MPa.

7. The neutron capture therapy system according to claim 1, characterized in that: More than 90% (by weight) of the material of the reinforcement portion is composed of at least one element of C, H, O, N, Si, Al, Mg, Li, B, Mn, Cu, Zn, S, and Ca. The half-life of the radioactive isotope generated by the reinforcement portion after neutron activation is less than 1 year. The material of the reinforcement portion is at least partially aluminum alloy or carbon fiber composite material or glass fiber composite material.

8. The neutron capture therapy system according to claim 1, characterized in that: The neutron capture therapy system also includes a treatment table and a collimator. The collimator is arranged at the rear of the beam outlet to converge the neutron line. The neutron line generated by the neutron generating device is irradiated toward the irradiated object on the treatment table through the beam shaper and the collimator. A radiation shielding device is arranged between the irradiated object and the beam outlet to shield the radiation of the beam exiting the beam outlet to the normal tissue of the irradiated object.

9. The neutron capture therapy system according to claim 1, characterized in that: The neutron capture therapy system also includes a charged particle beam generating chamber and an irradiation chamber. The irradiated object on the treatment table is treated with neutron beam irradiation in the irradiation chamber. The charged particle beam generating chamber accommodates the accelerator. The concrete wall includes a partition wall between the charged particle beam generating chamber and the irradiation chamber. The beam shaping body is supported on a reinforcement portion at least partially disposed in the partition wall.

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