36 results about "Neutron multiplication" patented technology

An accelerator-driven subcritical breeding reactor is operated with a neutron multiplication coefficient as large as possible in order to require a small input power from the accelerator, reducing its dimension and hence its cost and complexity. The beam-generated spallation neutron yield then becomes comparable to the fraction of delayed neutrons from the fissioned elements. This can be exploited to ensure an accurate on-line determination of the reactivity. Resulting changes can be adjusted with the help of neutron absorbing control rods and / or variations of the proton current. In addition, the temperature variations during operation can be continuously monitored and adjusted in order to avoid that the subcritical systems approaches too closely the (delayed) criticality condition and that the neutron multiplication coefficient remains within acceptable limits.

The invention belongs to the field of cladding designs of a fusion and fission hybrid reactor, and particularly relates to a Th-U self-sustaining circulating full fused salt fuel hybrid reactor system and an operation method thereof. The Th-U self-sustaining circulating full fused salt fuel hybrid reactor system is characterized in that a fast fission breeder reactor provides an initial easily fission fuel required by starting of a thermal fission reactor, a cladding design of the thermal fission reactor utilizes an arrangement strategy of a seed-cladding to improve the entirety neutron economy of the system, and the purposes of a high energy enlargement factor of the system, tritium breeding and thorium-uranium self-sustaining circulating of the system are realized; <233>U is loaded in an energy generating region, so that the energy generating region has a good neutronics property and is mainly used for realizing the purposes of energy amplification of the system, neutron multiplication and most <233>U breeding of the system; superfluous neutrons enter a tritium producing region and are used for tritium breeding and part of <233>U breeding of the system. According to the hybrid reactor, due to self-sustaining circulating of thorium and uranium, a thorium fuel is converted into <233>U and is gradually burn up in an operation process, and the Th-U self-sustaining circulating full fused salt fuel hybrid reactor system can effectively and stably operate for a long time just by gradually adding the thorium fuel and removing the generated fission product.

The invention discloses a heavy-metal-multiplication wide-energy neutron source intensity measurement system, which can be suitable for single-energy or wide-energy neutron radiation field source intensity measurement and value transfer of a high-energy accelerator and a reactor and the like. The system comprises a neutron probe, a signal processing system and a data analysis system. The neutron probe is formed by a central thermal neutron detector, an inner-layer moderator, a neutron multiplication layer, a peripheral thermal neutron detector, a reflecting layer, a lateral thermal neutron absorber, an external-layer moderator and a forward thermal neutron absorber. The central thermal neutron detector adopts a position-sensitive neutron detector to obtain energy spectrum information of aradiation field; and an energy weighting factor is set to compensate for energy response of the central thermal neutron detector, thereby improving measurement precision. The system is novel in structure, wide in energy range and good in angle response performance, can carry out energy response compensation and is high in source intensity measurement precision and the like.

A first intensity Az expressed as Az=az×Eα, a first reference intensity Ao expressed as Ao=ao×Eα, a second intensity Bz expressed as Bz=bz×E, and a second reference intensity Bo=bo×E, are evaluated. The first intensity and the first reference intensity are of radioactive nuclides generated by a neutron capture reaction of a heavy nuclide or a fission product nuclide. The second intensity and the second reference intensity are of radioactive fission product nuclides except nuclides generated by a neutron capture reaction. The reference intensities are measured where the void fraction is known. Also a correlation curve of (az / ao) and a void fraction is evaluated. Finally an axial void fraction distribution is evaluated based on the value of (az / ao) and the correlation curve.

The invention relates to a novel test blanket testing device for tritium breeding and heat rejection. The novel test blanket testing device comprises sub-modules; each sub-module comprises a first U-shaped wall, an upper cover plate, a lower cover plate and a sub-module backboard system so as to act as an outer boundary; a middle plate is arranged in each sub-module; two sides of the middle plate are provided with two groups of double-layer U-shaped helium cooling plates; the internal part of the sub-module is divided into neutron multiplication regions and tritium breeding regions by the double-layer U-shaped helium cooling plates and the middle plate; and the sub-module backboard system is provided with a helium cooling pipeline communicated with the double-layer U-shaped helium cooling plates, the cover plates and the middle plate and a tritium extraction pipeline communicated with the tritium breeding regions and the neutron multiplication regions. According to the novel test blanket testing device, a modularized structure is adopted; the double-layer U-shaped cooling plates are adopted in the sub-modules, and structural arrangement, which is conducive to tritium breeding, of the neutron multiplication regions and the tritium breeding regions, is formed; and a bypass is adopted, and therefore, control on the flow rate of a cooling agent can be benefitted, and realization of tritium breeding and efficient energy extraction under the premise of stable and safe operation of an ITER test window can be ensured.

The invention discloses a fusion reactor water-helium cold ceramic breeder cladding, which comprises parts such as a first wall, a cooling plate, separators and side plates. The cladding simultaneously adopts water and helium as a coolant, the water is used for cooling the first wall, and the helium is used for cooling the parts except the first wall. The first wall is a U-shaped plate; the cooling plate is in a shape like a Chinese character ao; the cooling plate is located at the inner side of the first wall and is connected with the side wall of the first wall; the cooling plate is crossed with the separators and the side plates, the inner space of the cladding is divided to multiple independent cavities arranged along a radial direction, cavities contacted with the first wall are filled with Li2TiO3 / Be12Ti mixed ball beds as tritium breeding zones, and cavities not contacted with the first wall are filled with Be ball beds as neutron multiplication zones. The fusion reactor water-helium cold ceramic breeder cladding has the advantages that the surface heat flow endurance capability is strong, the tritium production performance is good, the coolant outlet temperature is high, the coolant is well compatible with the neutron multiplication zone material, the flow of the coolant is easy to control, and the development prospect is good.

An accelerator-driven subcritical breeding reactor is operated with a neutron multiplication coefficient as large as possible in order to require a small input power from the accelerator, reducing its dimension and hence its cost and complexity. The beam-generated spallation neutron yield then becomes comparable to the fraction of delayed neutrons from the fissioned elements. This can be exploited to ensure an accurate on-line determination of the reactivity. Resulting changes can be adjusted with the help of neutron absorbing control rods and / or variations of the proton current. In addition, the temperature variations during operation can be continuously monitored and adjusted in order to avoid that the subcritical systems approaches too closely the (delayed) criticality condition and that the neutron multiplication coefficient remains within acceptable limits.

The invention belongs to the field of fusion and fission hybrid energy reactors and cladding design, and particularly relates to a hybrid reactor system arranged by means of water-cooling thorium fuel modules and water-cooling uranium fuel modules in a staggered mode and an operating method. Natural thorium fuel reaction modules and natural uranium fuel reaction modules are annularly and alternately arranged in an optimized mode, a seed-cladding strategy is made full use of to improve overall neutron economy of the system, the aim of making the best of thorium fuel under high-energy magnification is achieved, namely good neutron performance of the water-cooling natural uranium modules is used for compensating for defects of natural thorium neutron multiplication and energy amplification, achievement of energy amplification and neutron multiplication of the system mainly depends on natural uranium, and redundant neutrons generated from the natural uranium are used for driving natural thorium to operate and multiplying 233U. When 233U in the natural thorium is accumulated to a certain quantity, the natural uranium can be extracted step by step and replaced by new natural thorium, a hybrid reactor can be filled with thorium fuel ultimately, and cycle operations of thorium and uranium are achieved.

The invention discloses a multi-type neutron energy spectrum regulation and control target apparatus. The apparatus comprises a coupled target reaction apparatus and a target replacing apparatus in aneutron energy spectrum regulation and control apparatus. The apparatus is applied to a fusion neutron source driven sub-critical mixed pile energy system; deuterium beam generated by a strong flow deuterium tritium fusion neutron generator bombards a solid-state target to generate a high-flux deuterium tritium fusion neutron beam; then the fusion neutron bombards a sub-critical coating layer witha neutron multiplication material; through neutron multiplication and energy spectrum optimization, neutron energy spectrum regulation and control is realized; the coupled target reaction apparatus comprises a vacuum tube, a target tube and a target sheet assembly positioned in the target tube; and the target replacing apparatus comprises a target replacing cavity, a target sheet storage cavity,a target sheet replacing apparatus, and a target sheet conveying apparatus for conveying the target sheet assembly to the target pipe. Labor intensity of the working staff in target replacing is lowered effectively, meanwhile, the target replacing efficiency is improved, and operational stability of a clean energy system is improved.

The invention relates to a neutron detection technology, and discloses a neutron detection cathode, a neutron detector and a neutron detection method. The neutron detection cathode converts neutrons and releases electrons after the incidence of neutrons, and then detects neutron signals indirectly by detecting the electrons. The neutron detection cathode includes a support substrate, an electrodelayer and a neutron capture layer. The electrode layer is arranged on the support substrate. The neutron capture layer is arranged on the other side, opposite to the support substrate, of the electrode layer. The neutron capture layer contains a neutron capture material, and the neutron capture material captures neutrons and then releases electrons. A neutron multiplication detection device further includes a vacuum vessel, a dynode and an anode. The vacuum vessel has an incident window. The electrode layer covers the inner surface of the incident window of the vacuum vessel. The neutron capture layer covers the inner surface of the electrode layer. Thus, accurate multiplication detection or direct detection can be carried out on electrons converted from neutrons through the capture layer,and thermal neutrons can be sensitively detected.

A novel cladding structure for a fusion reactor comprises a U-shaped first wall, cover plates, a front back plate, a rear back plate and a proliferation unit, the U-shaped first wall and the upper andlower cover plates are internally provided with slots, and the upper and lower cover plate and the U-shaped first wall are welded to the front and rear back plates, thereby forming a sealed outer box. The proliferation unit is inserted in the front and rear back plates to be fixedly connected, an internal tritium proliferation agent is wrapped by a cooling plate in the form of a pebble bed, and the pebble bed and the cooling plate are sealed in a neutron multiplication agent. The front and rear back plates and the upper and lower cover plate and the U-shaped first wall form a six-layer platelike gas header which is used for collecting and reallocating coolants and purge gas. According to the novel cladding structure for a fusion reactor, on the premise of ensuring a module proliferation effect, a central area adopts an M-shaped cooling channel, thus a cooling effect can be better improved, and installation procedures are reduced, thereby facilitating replacement and maintenance.

The invention discloses a <99>Mo sub-critical production device and method based on accelerator driving. The <99>Mo sub-critical production device based on accelerator driving comprises an acceleratorunit, a radiation production unit and a separation and purification unit; the accelerator unit sequentially comprises a high-energy particle source, a collimator, an accelerator, a target and a target cavity in an output direction; the high-energy particle source accurately bombards the target positioned in the target cavity at the center of the radiation production unit through the collimator and the accelerator to generate neutron; the radiation production unit adopts a concentric cylindrical structure and sequentially comprises neutron slowing layer, a neutron multiplying layer, a low enriched uranium salt solution and a neutron reflecting layer from inside to outside; and the low enriched uranium salt solution is placed into a fission reaction container to be sealed, the reflecting neutron generated by the target in the target cavity passes through the neutron slowing layer and the neutron multiplying layer to obtain high neutron flux and react with the low enriched uranium salt solution, the solution after reaction enters the separation and purification unit through a pipeline, and the neutron reflecting layer and a shielding layer are arranged sequentially from inside to outside, are positioned on an outer layer and are used for reducing neutron loss.

A first intensity Az expressed as Az=az×Eα, a first reference intensity A0 expressed as A0=a0×Eα, a second intensity Bz expressed as Bz=bz×E, and a second reference intensity B0=b0×E, are evaluated. The first intensity and the first reference intensity are of radioactive nuclides generated by a neutron capture reaction of a heavy nuclide or a fission product nuclide. The second intensity and the second reference intensity are of radioactive fission product nuclides except nuclides generated by a neutron capture reaction. The reference intensities are measured where the void fraction is known. Also a correlation curve of (az / a0) and a void fraction is evaluated. Finally an axial void fraction distribution is evaluated based on the value of (az / a0) and the correlation curve.

The invention discloses a neutron energy spectrum measurement device and a measurement method thereof. A neutron gamma ray information conversion device of the neutron energy spectrum measurement device comprises a thermal neutron capture material, a fast neutron moderator, a fast neutron inelastic scattering material and a high-energy neutron multiplication material which are of a concentric sphere structure, wherein the central gamma detector is arranged in the center of the concentric sphere, the multilayer thermal neutron capture material, the single-layer fast neutron moderator, the multilayer fast neutron inelastic scattering material and the single-layer high-energy neutron multiplication material sequentially wrap the central gamma detector from inside to outside, and the data acquisition and processing system is electrically connected with the central gamma detector. The device is advantaged in that instantaneous gamma rays generated by reaction of neutrons and various nuclides with different neutron reaction sections are detected through the central gamma detector, and a neutron energy spectrum is reversely deduced through the data acquisition and processing system by utilizing the energy and intensity of characteristic gamma rays and information of various nuclide materials, so detection efficiency of the system is effectively improved; and on-line measurement of theneutron energy spectrum in the wide energy region is realized.

The invention discloses a <99>Mo sub-critical production device and method based on accelerator driving. The <99>Mo sub-critical production device based on accelerator driving comprises an acceleratorunit, a radiation production unit and a separation and purification unit; the accelerator unit sequentially comprises a high-energy particle source, a collimator, an accelerator, a target and a target cavity in an output direction; the high-energy particle source accurately bombards the target positioned in the target cavity at the center of the radiation production unit through the collimator and the accelerator to generate neutron; the radiation production unit adopts a concentric cylindrical structure and sequentially comprises neutron slowing layer, a neutron multiplying layer, a low enriched uranium salt solution and a neutron reflecting layer from inside to outside; and the low enriched uranium salt solution is placed into a fission reaction container to be sealed, the reflecting neutron generated by the target in the target cavity passes through the neutron slowing layer and the neutron multiplying layer to obtain high neutron flux and react with the low enriched uranium salt solution, the solution after reaction enters the separation and purification unit through a pipeline, and the neutron reflecting layer and a shielding layer are arranged sequentially from inside to outside, are positioned on an outer layer and are used for reducing neutron loss.

The invention provides a pebble-bed high-temperature gas cooled reactor high neutron multiplication performance fuel element. The element comprises a graphite cladding and a graphite matrix from outside to inside, wherein a plurality of coated fuel particles are uniformly distributed in the graphite matrix according to spherical coordinates, each coated fuel particle comprises a uranium dioxide core particle and a coating layer from inside to outside in the radial direction, each coating layer sequentially comprises a loose pyrolytic carbon layer, an inner compact pyrolytic carbon layer, a silicon carbide layer and an outer compact pyrolytic carbon layer from inside to outside, and the thickness of each layer of the coating layer is obtained by multi-objective optimization under the condition that the diameter and the enrichment degree of the uranium dioxide core particles are fixed. According to the invention, the neutron multiplication performance is improved from the perspective ofoptimizing the thickness of each layer of the coating layer, the purpose of improving the neutron performance by simply increasing the diameter or the enrichment degree of the core particles in the past is avoided, and experiments prove that the neutron performance is improved, and the pebble-bed high-temperature gas cooled reactor high neutron multiplication performance fuel element has very strong economic advantages.

A hexagon accelerator driven subcritical reactor fuel assembly and a design method thereof are disclosed. The assembly includes a hexagon base the top surface of which is provided with a plurality ofbase units for fuel rod mounting, with one of the base units being at the center of the base, other base units surrounding the center base unit and being arranged in an annular array manner, distancesbetween adjacent base units being equal; a shell including a prismatic sleeve the cross section of which adapts to the shape of the base and the bottom of which is mounted on the base; an inner sleeve including a prismatic sleeve, disposed inside the shell with a gap between the inner sleeve and the shell, with the bottom of the inner sleeve being mounted on the base; and a plurality of fuel rods, wherein each fuel rod includes a cylindric casing and a core rod in the casing and made of fuel, the bottom of each casing is mounted in one base unit, and the number of the fuel rods is equal to the number of the base units. The assembly and the method are used for solving a problem that neutron performance is poor, and technical effects that economic performance and neutron performance are high are achieved.

The invention discloses a lead-based neutron multiplier suitable for a fusion reactor solid cladding, which adopts a composite sphere design of a three-layer core-shell structure: a PbxMy sphere core material is a lead-based intermetallic compound with high melting point and excellent neutron multiplication performance, including but not limited to LaPb3, CePb3, Zr5Pb4, Zr5Pb3, PrPb3, NbPb3, Nd5Pb4, Nd5Pb3 and PbS, and plays a role in neutron multiplication; the middle shell layer is a PbxMy-Li2O metal ceramic composite material, the comprehensive tritium breeding ratio of the cladding is improved through efficient tritium production of Li2O and fusion neutrons, meanwhile, the metal ceramic composite material and a PbxMy metal interface have good thermodynamic matching, and the overall core-shell structure is stable; and the PbxMy shell layer is a thin film, so that the overall chemical inertness of the spherical shell is ensured. The invention provides a neutron multiplier design which is good in economical efficiency and can meet the fusion reactor tritium breeding requirement, and a feasible solution can be provided for replacing pure beryllium.

The invention belongs to the field of fusion and fission hybrid energy reactors and cladding design, and particularly relates to a hybrid reactor system arranged by means of water-cooling thorium fuel modules and water-cooling uranium fuel modules in a staggered mode and an operating method. Natural thorium fuel reaction modules and natural uranium fuel reaction modules are annularly and alternately arranged in an optimized mode, a seed-cladding strategy is made full use of to improve overall neutron economy of the system, the aim of making the best of thorium fuel under high-energy magnification is achieved, namely good neutron performance of the water-cooling natural uranium modules is used for compensating for defects of natural thorium neutron multiplication and energy amplification, achievement of energy amplification and neutron multiplication of the system mainly depends on natural uranium, and redundant neutrons generated from the natural uranium are used for driving natural thorium to operate and multiplying 233U. When 233U in the natural thorium is accumulated to a certain quantity, the natural uranium can be extracted step by step and replaced by new natural thorium, a hybrid reactor can be filled with thorium fuel ultimately, and cycle operations of thorium and uranium are achieved.

The invention discloses a non-centrosymmetric single-beam accelerator driven subcritical reactor. The single-beam accelerator driven subcritical reactor comprises a proton beam, a spallation target, a fuel area and a radiation shielding layer, the radiation shielding layer wraps the periphery of the fuel area, the spallation target is located at a non-central position in the fuel area, and is inserted into the fuel area in a penetrating manner along the axial direction, and a proton beam is inserted into the spallation target along one axial end of the spallation target. According to the single-beam accelerator driven subcritical reactor provided by the invention, the proton beam and the spallation target are arranged at the non-central position of the fuel area, and under the same parameters, the neutron multiplication factor of the single-beam accelerator driven subcritical reactor provided by the invention is improved by 0.02399 compared with that of a centrosymmetric ADS; and the integral energy efficiency of the reactor is improved under the condition that the charging amount is not increased, high economic advantages are achieved, the refueling operation of the refueling mechanism is obviously simplified, engineering implementation is simpler, more convenient and safer, and the economical efficiency is better.

The invention relates to monitoring and testing of a nuclear reactor, specifically to a structure combination of a reactor core for measuring radioactivity and a sensitive instrument, and specificallyprovides a method for measuring reactivity. The reactivity of the reactor core can be evaluated without the need of putting a disturbance neutron source into the reactor core; experimental results and calculation results show that the method can evaluate the critical degree (reactivity) of the reactor by measurement of the neutron multiplication factor of an external neutron source, and providesa novel idea for measuring the reactivity of the reactor core under special working conditions.

The invention discloses a heavy-metal-multiplication wide-energy neutron source intensity measurement system, which can be suitable for single-energy or wide-energy neutron radiation field source intensity measurement and value transfer of a high-energy accelerator and a reactor and the like. The system comprises a neutron probe, a signal processing system and a data analysis system. The neutron probe is formed by a central thermal neutron detector, an inner-layer moderator, a neutron multiplication layer, a peripheral thermal neutron detector, a reflecting layer, a lateral thermal neutron absorber, an external-layer moderator and a forward thermal neutron absorber. The central thermal neutron detector adopts a position-sensitive neutron detector to obtain energy spectrum information of aradiation field; and an energy weighting factor is set to compensate for energy response of the central thermal neutron detector, thereby improving measurement precision. The system is novel in structure, wide in energy range and good in angle response performance, can carry out energy response compensation and is high in source intensity measurement precision and the like.

The invention discloses a fusion reactor water-helium cold ceramic breeder cladding, which comprises parts such as a first wall, a cooling plate, separators and side plates. The cladding simultaneously adopts water and helium as a coolant, the water is used for cooling the first wall, and the helium is used for cooling the parts except the first wall. The first wall is a U-shaped plate; the cooling plate is in a shape like a Chinese character ao; the cooling plate is located at the inner side of the first wall and is connected with the side wall of the first wall; the cooling plate is crossed with the separators and the side plates, the inner space of the cladding is divided to multiple independent cavities arranged along a radial direction, cavities contacted with the first wall are filled with Li2TiO3 / Be12Ti mixed ball beds as tritium breeding zones, and cavities not contacted with the first wall are filled with Be ball beds as neutron multiplication zones. The fusion reactor water-helium cold ceramic breeder cladding has the advantages that the surface heat flow endurance capability is strong, the tritium production performance is good, the coolant outlet temperature is high, the coolant is well compatible with the neutron multiplication zone material, the flow of the coolant is easy to control, and the development prospect is good.

A method of controlling the criticality of a nuclear fuel cycle facility includes steps of producing a reactor fuel by adding less than 0.1% by weight of gadolinia to a uranium dioxide powder with a uranium enrichment of greater than 5% by weight and controlling the effective neutron multiplication factor of a uranium dioxide system in a step of handling the reactor fuel to be less than or equal to the maximum of the effective neutron multiplication factor of a uranium dioxide system with a uranium enrichment of 5% by weight.

The invention belongs to the field of cladding designs of a fusion and fission hybrid reactor, and particularly relates to a Th-U self-sustaining circulating full fused salt fuel hybrid reactor system and an operation method thereof. The Th-U self-sustaining circulating full fused salt fuel hybrid reactor system is characterized in that a fast fission breeder reactor provides an initial easily fission fuel required by starting of a thermal fission reactor, a cladding design of the thermal fission reactor utilizes an arrangement strategy of a seed-cladding to improve the entirety neutron economy of the system, and the purposes of a high energy enlargement factor of the system, tritium breeding and thorium-uranium self-sustaining circulating of the system are realized; <233>U is loaded in an energy generating region, so that the energy generating region has a good neutronics property and is mainly used for realizing the purposes of energy amplification of the system, neutron multiplication and most <233>U breeding of the system; superfluous neutrons enter a tritium producing region and are used for tritium breeding and part of <233>U breeding of the system. According to the hybrid reactor, due to self-sustaining circulating of thorium and uranium, a thorium fuel is converted into <233>U and is gradually burn up in an operation process, and the Th-U self-sustaining circulating full fused salt fuel hybrid reactor system can effectively and stably operate for a long time just by gradually adding the thorium fuel and removing the generated fission product.

A novel cladding structure for a fusion reactor comprises a U-shaped first wall, cover plates, a front back plate, a rear back plate and a proliferation unit, the U-shaped first wall and the upper andlower cover plates are internally provided with slots, and the upper and lower cover plate and the U-shaped first wall are welded to the front and rear back plates, thereby forming a sealed outer box. The proliferation unit is inserted in the front and rear back plates to be fixedly connected, an internal tritium proliferation agent is wrapped by a cooling plate in the form of a pebble bed, and the pebble bed and the cooling plate are sealed in a neutron multiplication agent. The front and rear back plates and the upper and lower cover plate and the U-shaped first wall form a six-layer platelike gas header which is used for collecting and reallocating coolants and purge gas. According to the novel cladding structure for a fusion reactor, on the premise of ensuring a module proliferation effect, a central area adopts an M-shaped cooling channel, thus a cooling effect can be better improved, and installation procedures are reduced, thereby facilitating replacement and maintenance.

The invention provides an efficient neutron conversion screen, and relates to the technical field of neutron photography; an efficient neutron conversion screen is composed of a neutron multiplication layer, a fluorescent layer and a high-purity duralumin plate; wherein the high-purity duralumin plate is coated with the fluorescent layer in a uniform smearing mode, and the fluorescent layer is coated with the neutron multiplication layer in a uniform smearing mode; a neutron multiplication material is placed in the neutron multiplication layer, wherein neutron multiplication is carried out through fission or (n, 2n) or (n, 3n) and other reactions, the number of neutrons reaching the fluorescent layer is increased, and then light emitted after passing through the neutron conversion screen is enhanced. The neutron signal reaching the conversion screen can be amplified, and formation of a clear image and shortening of imaging time are facilitated even under the condition of a weak source or a thick sample to be detected.

The invention provides a <99>Mo subcritical production device based on a Th-U self-sustaining cycle. The <99>Mo subcritical production device comprises an accelerator system, a <99>Mo production system and a separation and purification unit; the accelerator system is used for accelerating and transporting ion beams and generating neutrons; the <99>Mo production system sequentially comprises a neutron multiplication layer, a <232>Th-<233>U salt solution, a neutron reflection layer and a shielding layer from inside to outside; the neutron multiplication layer is used for generating high neutron flux; the <232>Th-< 233>U salt solution is used for <233>U(n, f)<99>Mo reaction to produce < 99>Mo, and meanwhile, neutrons react with <232>Th to be converted into <233>U, so that the self-sustaining cycle of the <232>Th-<233>U is achieved; and the separation and purification unit is used for separation and purification of <99>Mo. The invention further provides a <99>Mo subcritical production method. The device and the method are simple in structure and process, low in cost and high in <99> Mo yield, the Th-U self-sustaining cycle is met, and no extra fuel needs to be added within 15 years.

The invention discloses a fusion reactor solid water cooled blanket tritium proliferating-neutron multiplying agent. A composite core-shell spherical structure is adopted, the core is a beryllium sphere, the shell is ceramic state lithium titanate, and the ceramic state lithium titanate wraps the beryllium sphere. In order to increase the filling factor, the tritium yield of the water cooled blanket is increased, and a two-component sphere bed form with an optimized diameter ratio is adopted. A water cooled blanket filled by the novel proliferating-multiplying agent can overcome the problem that beryllium taken as a neutron multiplying agent may contact with water in an accident, and hydrogen is generated; and thus the safety of the water cooled blanket is effectively improved. Furthermore, multiplied neutrons generated by the beryllium core of the proliferating-multiplying agent spheres must go through the proliferation layer that wraps the core during the releasing process, in a macroscopic view, the happening rate of reactions between neutrons and the proliferating agent is increased, and thus the total tritium yield of the blanket is increased.