247results about "Neutron sources" patented technology

The design of a compact, high-efficiency, high-flux capable compact-accelerator fusion neutron generator (FNG) is discussed. FNG's can be used in a variety of industrial analysis applications to replace the use of radioisotopes which pose higher risks to both the end user and national security. High efficiency, long lifetime, and high power-handling capability are achieved though innovative target materials and ion source technology. The device can be scaled up for neutron radiography applications, or down for borehole analysis or other compact applications. Advanced technologies such as custom neutron output energy spectrum, pulsing, and associated particle imaging can be incorporated.

A novel method and compact neutron source for generating thermal neutrons is described that uses an ion source to emit ions toward a target where neutrons are generated. Surrounding the target is a secondary electron shield, and surrounding the target is a first stage moderator to reduce the energy of generated fast neutrons. Enclosing the first stage moderator is a second stage moderator with a thermal neutron port.

A therapy apparatus for producing thermal neutrons at a tumor site in a patient has a plurality of fast neutron sources surrounding a moderator, a fast neutron reflecting media around the fast neutron sources, a gamma-ray and neutron shielding media surrounding the fast neutron reflecting media, and a patient chamber positioned inside the moderator. The fast neutron sources are positioned around the moderator to maximize and direct the neutron flux to said tumor site.

The invention discloses a small neutron source adopting a windowless gas target, which belongs to the field of nuclear technology and application. In the invention, an ECR (Electron Cyclotron Resonance) ion source is used for generating a deuterium ion and directly extracted by a high-voltage extraction electrode for bombarding a windowless gas target sealed by a plasma; because the windowless deuterium gas target is sealed by adopting the plasma, the windowless deuterium gas target is allowed to bear high-flow-strength beam current; and because the energy loss of the deuterium ion when penetrating through a plasma window is less, the neutron yield is higher. Compared with a neutron pipe, the neutron source provided by the invention has high allowed beam current strength and high neutron yield. Compared with an accelerator neutron source with large size, complex system and high cost, the neutron source provided by the invention has small size, simple system and low cost. Compared with a neutron source for directly carrying out deuterium-tritium reaction on an ion source to generate neutron, the ion source has simple system, low cost and no tritium radioactive processing and circulating problem. The invention has very wide application prospect.

Disclosed is a filter including a second layer disposed between a first layer and a third layer. The first layer is composed of iron. The second layer is composed of 1 part by volume of lithium fluoride, 20 to 50 parts by volume of aluminum, and 50 to 80 parts by volume of aluminum fluoride. The third layer is composed of 1 part by weight of lithium fluoride and 99 to 100 parts by weight of magnesium fluoride.

A portable neutron generator includes a Radio Frequency Quadrupole linear accelerator designed to accelerate charged particles of hydrogen (protons) to energies useful for producing neutrons with the (p,n) reaction on lithium. The ion source is driven by a coaxial feed and a spiral antenna to couple the microwave power into the plasma. The linear accelerator is driven by a 600 MHz pulsed RF power supply. A differential pumping scheme is used to balance the need for a high gas load on the ion source end and good vacuum on the accelerator end.

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.

A system for radioisotope production uses fast-neutron-caused fission of depleted or naturally occurring uranium targets in an irradiation chamber. Fast fission can be enhanced by having neutrons encountering the target undergo scattering or reflection to increase each neutron's probability of causing fission (m, f) reactions in U-238. The U-238 can be deployed as layers sandwiched between layers of neutron-reflecting material, or as rods surrounded by neutron-reflecting material.

An object of the present invention is to provide a beam source capable of efficiently generating a high-density energy beam having good directivity and a relatively large beam diameter. The beam source of the present invention comprises a discharge tube; a gas inlet for introducing gas into the discharge tube; three electrodes mounted in the discharge tube downstream from the gas inlet, wherein the electrode on the upstream end has a plurality of openings through which the gas can pass, the middle electrode is a mesh-shaped electrode, and the electrode on the downstream end is a beam-emitting electrode having a plurality of beam-emitting holes and is disposed in a plane parallel to the middle electrode; plasma-generating means disposed between the two upstream electrodes on the outside of the discharge tube for transforming gas introduced into the discharge tube into plasma; and voltage-applying means for accelerating the beam between the two downstream electrodes and emitting the accelerated beam from the downstream beam-emitting electrode.

Provided are a long-lived target for a neutron-generating device and a method for manufacturing the target therefore. The target is for a neutron-generating device and includes: a metal substrate retaining a target material; and a metal thin film for sealing that holds the target material at a retention surface X side. The retention surface X side of the metal substrate includes: a frame portion; and an embossed structure including: a plurality of island portions that are surrounded by the frame portion; and the rest recessed portion that is created by decreasing a thickness of a region other than the frame portion and the island portions by a thickness of the target material. The metal thin film and surfaces of the frame portion and the island portions are subjected to hot isostearic pressing (HIP) bonding to seal the target material onto the recessed portion by using the metal thin film.

An apparatus for producing thermal or epithermal neutrons in a sample has a plurality of fast neutron sources positioned around a cylindrical or spherical moderator to maximize the neutron flux at a sample placed in a void at the center of the moderator.

The invention relates to a reactor core component of a neutron source device of a hospital neutron irradiator-I. The reactor core component has the advantages of being low in production cost, easy and convenient to operate and maintain, safe to use, low in operation cost, pollution-free to environment and can be built directly in hospitals and the like, so that the reactor core component is an ideal device as a neutron source of the neutron irradiator. The device realizes innovation and invention of the four reactor core important components, such as a high-equivalent central control rod, a high-effect responsive regulator, a graphite tile and aluminium tile piece adaptive to neutron spectrum as well as low-concentration design of a reactor core fuel element and update of fuel assembly structure material and the like. On the basis that the intrinsic security of a reactor and extremely-low uranium filling volume are maintained and operation is done under nuclear-free engineering personnel caring conditions, the reactor for scientific research which is only used in small sample element activation analysis is developed to be a high-tech clinic cancer-curing medical instrument. The specially-designed reactor core component forms the four mutually-associated invention points in the invention.

The invention provides a liquid target system which comprises a beam current action zone and a neutron generating device arranged in the beam current action zone. The neutron generating device is made of fissile material. The output rate of neutrons can be effectively increased.

Gamma radiation (22) is shielded by producing a region of heavy electrons (4) and receiving incident gamma radiation in such region. The heavy electrons absorb energy from the gamma radiation and re-radiate it as photons (38, 40) at a lower energy and frequency. The heavy electrons may be produced in surface plasmon polaritons. Multiple regions (6) of collectively oscillating protons or deuterons with associated heavy electrons may be provided. Nanoparticles of a target material on a metallic surface capable of supporting surface plasmons may be provided. The region of heavy electrons is associated with that metallic surface. The method induces a breakdown in a Born-Oppenheimer approximation Apparatus and method are described.

The invention relates to a generation device of a controllable isotopic neutron source. The generation device of the controllable isotopic neutron source comprises an upper sealing barrel, a lower sealing barrel, an adjusting device, a sealing device, a beryllium sheet set and an alpha-particle emission nuclide plating sheet set. The adjusting device comprises a rotary main rod and a rotary handle, wherein the rotary main rod is arranged at the upper end portion of the upper sealing barrel and can rotate on its axis, and the rotary handle is fixed at the top end of the rotary main rod. The sealing device comprises a corrugated pipe and a connecting body, wherein the connecting body comprises a bottom face and a threaded hole, the threaded hole is formed in the bottom face, and an opening of the threaded hole faces upwards. The upper sealing barrel and the lower sealing barrel are in sealed connection, the corrugated pipe is arranged in the lower sealing barrel, an opening in the upper end of the lower sealing barrel is in sealed connection with an opening in the lower end of the upper sealing barrel, and an opening in the lower end of the lower sealing barrel is sealed with the bottom face of the connecting body. The generation device of the controllable isotopic neutron source aims to solve the problem that due to the uncontrollability of the isotopic neutron source, the safety, the motility and the like are poor. Neutrons appear and disappear by controlling two kinds of reactive nuclides to be closed or separated, and the purpose of controllability is achieved.

A neutron emitting assembly, which is useful in nuclear reactors and other industrial applications, is made of a major amount of beryllium encapsulating a minor amount of 252Cf, which can be placed in a capsule having end plugs and a holding spring.

The invention relates to a high thermal power target system suitable for deuterium and tritium fusion neutron sources. The system includes a deuterium beam, a beam scanning drive device, a target slice, a target slice drive device, a cooling structure, a cooling medium, a cooling medium circulation system, a beam transmission chamber, a cooling medium dynamic sealing structure, and a vacuum dynamic sealing structure. The beam scanning drive is used to drive the deuterium beam to move. The deuterium beam is located in the beam transmission chamber. The target slice drive device drives the target slice to move. The target slice is disposed on the moving path of the deuterium beam. The deuterium beam bombards a target spot formed by the target slice. The cooling structure is located in the target slice area where the target spot is located. The cooling medium is filled in the cooling structure. The cooling medium is circulated through the cooling medium circulation system. According to the invention, the tritium target system for the high intensity deuterium and tritium fusion neutron sources can maintain a target surface temperature of less than 200 DEG C when being subjected to bombardment with a deuterium beam of greater than 100 kw / cm2, the stable operation of the tritium target system is ensured, and then 14MeV high-energy fusion neutrons with neutron sources up to 1013 to 1015n / s are produced.

A system for generating a source of neutrons from a thermonuclear fusion reaction includes a reaction chamber and a number of particle beam emitters. The reaction system has at least four particle beam emitters supported spatially around oriented toward a common focal region of the reaction chamber for directing the plurality of plasma beams that are spatially symmetrical in three dimensional space. Each of the plasma beams are directed towards a plasma region in the geometric center. A stable collapse of the plasma region permits a controllable and sufficiently long confinement time, which in combination with necessary temperature and density conditions may ignite and sustain fusion reactions and achieve a net energy output. Optionally, laser beams or other input energy devices may also be oriented around and toward the common focal region to direct high-energy laser beams at the plasma ball to assist with instigation of the fusion reaction. The thermonuclear reaction system may be used as a neutron source for nuclear power reactors.

A spallation device for production of neutrons includes a solid spallation target that produces neutrons by interaction with a hollow particle beam propagating within a first chamber, a second chamber containing the spallation target, and a leak tight partition separating the first and second chambers.

A radiation detection system and method for a neutron capture therapy system, which may increase the accuracy of neutron beam irradiation dose of the neutron capture therapy system and find out a fault position in time. The neutron capture therapy system includes a charged particle beam, a charged particle beam inlet allowing the charged particle beam to pass through, a neutron beam generating unit which may generate a neutron beam after a nuclear reaction occurs between the neutron beam generating unit and the charged particle beam, a beam shaping assembly for adjusting the flux and the quality of the neutron beam generated by the neutron beam generating unit, and a beam outlet adjacent to the beam shaping assembly, the radiation detection system includes a radiation detection device for real-time detection of γ rays instantly emitted under neutron beam irradiation.

The invention provides a radioactive isotope neutron source, which comprises a source core and a shell, wherein the source core is a ceramic body. The preferable source core of the neutron source comprises americium oxide and / or plutonium oxide and metal beryllium, wherein the granularity of the metal beryllium is between 100 and 200nm, and the americium oxide and / or the plutonium oxide and the metal beryllium are made into nanoscale particles by ball grinding in the preparation process. Additionally, the invention also provides a method for preparing the radioactive isotope neutron source. Because the source core is the ceramic body, the radioactive isotope neutron source has firm and stable source core, does not expand after being soaked in water and reduces the radioactive pollution. In addition, the nanoscale particles are formed in the source core by the ball grinding, so the internal metal beryllium particles are evenly distributed and have even sizes, and neutrons are evenly and stably output.

Apparatuses and methods for producing neutrons for applications such as boron neutron capture therapy (BNCT) are described. An apparatus can include a rotary fixture with a coolant inlet and a coolantoutlet, and a plurality of neutron-producing segments. Each neutron- producing segment of the plurality of neutron-producing segments is removably coupled to the rotary fixture, and includes a substrate having a coolant channel circuit defined therein and a solid neutron source layer disposed thereon. The coolant channel circuits are in fluid communication with the coolant inlet and the coolant outlet.

The invention provides a neutron source. A porous ion source is adopted for the neutron source, so as to educe deuterium ions or deuterium and tritium mixed ions with specific shapes and density distribution. Each educing hole is provided with corresponding initial focusing electrode and accelerating electrode; after being completed in acceleration, ion beams pass through an electric quadrupole field, and are focused to be in a required small size in a direction Z, and meanwhile, are defocused and spread to a certain length in a direction Y, so as to form a fan-shaped ion beam. The fan-shaped ion beam bombards a moving target; in the direction Y, an emergent neutron beam equivalent to a small-size focal-spot-shaped neutron source is generated. The neutron source which is provided by the invention is suitably applied to the fields, which have requirements on the directivity and the point source characteristic of a neutron beam, of neutron therapy, photography, explosives detection and the like.