Abstract: A neutron moderation material for use in a BNCT beam shaping assembly. The neutron moderation material comprises three elements, i.e., Mg, Al, and F, wherein the mass fraction of the Mg element is 3.5%-37.1%, the mass fraction of the Al element is 5%-90.4%, and the mass fraction of the F element is 5.8%-67.2%; the sum of the weights of the Mg, Al, and F elements is 100% of the total weight of the neutron moderation material. The neutron moderation material may be doped with a small amount of 6Li-containing substances, and the addition of the 6Li-containing substances effectively decreases the content of ?-rays in epithermal neutron beams.

Abstract: A beam shaping assembly for neutron capture therapy includes a beam inlet, a target having nuclear reaction with an incident proton beam from the beam inlet to produce neutrons forming a neutron beam defining a main axis, a moderator adjoining to the target, a reflector surrounding the moderator, a thermal neutron absorber adjoining to the moderator, a radiation shield arranged inside the beam shaping assembly and a beam outlet. The neutrons are moderated to epithermal neutron energies. The reflector leads the neutrons deviated from the main axis back, and a gap channel is arranged between the moderator and the reflector. The thermal neutron absorber is used for absorbing thermal neutrons so as to avoid overdosing in superficial normal tissue during therapy. The radiation shield is used for shielding leaking neutrons and photons so as to reduce dose of the normal tissue not exposed to irradiation.

Abstract: A beam shaping assembly for neutron capture therapy includes a beam inlet, a target having nuclear reaction with an incident proton beam from the beam inlet to produce neutrons forming a neutron beam defining a main axis, a moderator adjoining to the target, a reflector surrounding the moderator, a thermal neutron absorber adjoining to the moderator, a radiation shield arranged inside the beam shaping assembly and a beam outlet. The neutrons are moderated to epithermal neutron energies. An outer surface of the moderator includes at least a first tapered section. The reflector leads the neutrons deviated from the main axis back. The thermal neutron absorber is used for absorbing thermal neutrons so as to avoid overdosing in superficial normal tissue during therapy. The radiation shield is used for shielding leaking neutrons and photons so as to reduce dose of the normal tissue not exposed to irradiation.

Abstract: A shielding material for shielding radioactive ray and preparation method thereof. The shielding material consists of water, a cementing material, a fine aggregate material, a coarse aggregate material and an additive, wherein the fine aggregate material consists of a borosilicate glass powder and a barite sand, and the coarse aggregate material consists of a barite. A content of boron element in the borosilicate glass powder accounts for 0.5%-1% of the total weight of the shielding material. A content of barium sulfate in the barite sand and the barite accounts for 71%-75% of the total weight of the shielding material. Other contents include water, the cementing material and the additive, and a sum of contents of all components is 100% total weight of the shielding material.

Abstract: A beam shaping assembly for neutron capture therapy includes a beam inlet, a target having nuclear reaction with an incident proton beam from the beam inlet to produce neutrons forming a neutron beam defining a main axis, a moderator adjoining to the target, a reflector surrounding the moderator, a thermal neutron absorber adjoining to the moderator, a radiation shield arranged inside the beam shaping assembly and a beam outlet. The neutrons are moderated to epithermal neutron energies. The reflector leads the neutrons deviated from the main axis back, and a gap channel is arranged between the moderator and the reflector. The thermal neutron absorber is used for absorbing thermal neutrons so as to avoid overdosing in superficial normal tissue during therapy. The radiation shield is used for shielding leaking neutrons and photons so as to reduce dose of the normal tissue not exposed to irradiation.