9 results about "Nuclear graphite" patented technology

The invention discloses a treatment method for blocking open pores of nuclear graphite by adopting a silicon carbide nanostructure so as to prevent molten salt and molten metal from infiltrating graphite. Comprising the following steps: 1) mixing polycarbosilane and an organic solvent according to a mass concentration ratio of 50%-70% to form a solution, adding a catalyst to serve as a precursor solution, and completely immersing the precursor solution into graphite pores through vacuum infiltration or pressure infiltration; 2) placing the infiltrated graphite in a closed environment of 70-200 DEG C, hydrolyzing and curing the precursor solution to form a gel network, then drying in a vacuum environment of 0-300 DEG C, and forming an aerogel precursor in graphite holes; and 3) in an inert gas atmosphere or a vacuum environment, heating to 1300-1800 DEG C, and pyrolyzing the aerogel precursor to form the silicon carbide nanostructure. Compared with a traditional method, the method has the advantages of simple process, difficulty in failure, no change of the original performance of graphite and the like, and has relatively high economic value and application prospect.

The invention discloses a preparation method of modified high-carbon ferrochrome, and belongs to the technical field of nano modification. The method comprises the following steps: ultrasonically dispersing Fe-Cr alloy powder, a nano carbon material, a nitrogen source precursor and nano ceramic particles in an alcohol solvent, heating and stirring, sintering, and etching with hydrofluoric acid to obtain core-shell particles; adding the core-shell particles into the high-carbon ferrochrome matrix for mechanical stirring, and then adding graphene powder for smelting to obtain a modified melt; the modified melt is poured and subjected to directional solidification, and a modified casting is obtained; the casting is immersed in a hexamethylenetetramine ethanol solution, and a surface wear-resistant layer is formed through pyrolysis treatment and laser remelting; and the casting is quenched and tempered, and the modified casting with the surface nanocrystalline structure is obtained. The comprehensive performance of the high-carbon ferro-chrome is remarkably improved through synergistic modification of nanometer heterogeneous nucleation, graphene enhancement and surface nanometer crystallization.

A preparation method of isotropic coke for nuclear graphite, distillation of high-temperature coal tar to obtain fractional oil; the fractional oil is mixed with a solvent, and then flocculation separation is performed to obtain light phase oil and heavy phase oil; the light phase oil is subjected to distillation to recover the solvent, and then light purified tar is obtained; the heavy phase oil is subjected to distillation to recover the solvent, and then heavy tar is obtained; the heavy tar and the solvent are subjected to extraction separation to obtain a soluble phase and an insoluble phase; the soluble phase is subjected to distillation to recover the solvent, and then heavy purified tar is obtained; the light purified tar is subjected to multi-stage series hydrogenation to obtain fractional oil A; the heavy purified tar is subjected to hydrocracking to obtain fractional oil B; the fractional oil B is subjected to vacuum distillation to obtain fractional oil C; the fractional oil A is subjected to asphaltization reaction to obtain pre-polymerized asphalt; the fractional oil C and the pre-polymerized asphalt are mixed and subjected to liquid-phase carbonization to obtain mosaic structure green coke; the mosaic structure green coke is crushed and subjected to calcination to obtain isotropic coke for nuclear graphite. The coke has excellent physical and chemical properties, low manufacturing cost and short manufacturing period.

The application belongs to the technical field of photocatalytic functional materials, and specifically provides a core-shell-shell three-level structure composite material and a preparation method and application thereof, and belongs to the technical field of photocatalytic functional materials. The core-shell-shell three-level structure composite material takes an up-conversion micron particle as a core, graphite phase carbon nitride as an intermediate shell layer, and magnetic sepiolite as an outer shell layer. The core-shell combination of the UCMPs and g-C3N4 is realized through a one-step calcination method, the sepiolite is magnetically modified through a coprecipitation method, and finally, the core-shell-shell structure is formed through interface self-assembly. The obtained material has both photocatalytic activity and magnetic separation performance, the degradation efficiency of organic pollutants under simulated sunlight is increased by more than 257% compared with a single component, and the material can be quickly recycled and reused through an external magnetic field. The application has simple process and low cost, and is suitable for large-scale production.

A dual-optical-path nuclear graphite damage evolution and crack propagation whole-process deformation field measurement method comprises the following steps: constructing a fracture triggering mechanism, setting a low-speed high-resolution camera to continuously collect in a whole period, and capturing a crack image through a high-speed low-resolution camera when a triggering condition is met; a global high-precision deformation field of the surface of the test piece in a full loading period is solved through a digital image correlation method (PINN-DIC) based on a physical information neural network, a displacement field of the surface of the test piece in a high-speed fracture process is solved through the PINN-DIC while a damage feature region is identified, and crack core parameters are extracted; and in combination with strain distribution evolution characteristics and crack initiation positions, high-speed fracture information is mapped to a main coordinate system, and a cross-scale correlation mechanism is established. According to the method, accurate measurement and cross-scale data communication of the nuclear graphite damage evolution-fracture failure complete-period deformation field are realized, the deformation field measurement accuracy of a boundary region and a crack neighborhood is remarkably improved, and a key technical support is provided for analysis of a nuclear graphite fracture mechanism.

The invention belongs to the technical field of photocatalytic functional materials, and particularly provides a core-shell-shell three-stage structure composite material and a preparation method and application thereof, and belongs to the technical field of photocatalytic functional materials. The core-shell-shell three-stage structure composite material takes up-conversion micron particles as a core and graphite phase carbon nitride as a middle shell layer; the magnetic sepiolite is a shell layer; core-shell combination of UCMPs and g-C3N4 is achieved through a one-step calcination method, sepiolite is subjected to magnetic modification through a coprecipitation method, finally, a core-shell-shell structure is formed through interface self-assembly, the obtained material has photocatalytic activity and magnetic separation performance, the degradation efficiency on organic pollutants under simulated sunlight is improved by 257% or above compared with a single component, and the material has a good application prospect. The method can be quickly recycled through an external magnetic field, and is simple in process, low in cost and suitable for large-scale production.

The invention belongs to the technical field of resourceful treatment of retired nuclear graphite, and particularly relates to a resourceful treatment method of retired nuclear graphite. The treatment method comprises the following steps: (1) crushing a decommissioned graphite block into graphite powder; (2) uniformly mixing the graphite powder obtained in the step (1) with a brominating agent to obtain mixed powder; and (3) carrying out roasting treatment on the mixed powder obtained in the step (2) in an inert atmosphere at the roasting temperature of 900-1300 DEG C, so that the radioactive metal elements in the retired nuclear graphite form gaseous metal bromides and are volatilized from the retired nuclear graphite. According to the method disclosed by the invention, radioactive metal elements such as 59, 63Ni, 134, 137Cs, 152, 154 and 155Eu are roasted and recovered by adopting a 100% N2 inert atmosphere, so that the adsorption capacity between the radioactive metal elements and the surface of nuclear graphite is weakened, and meanwhile, a metal bromide which is low in melting point, high in saturated steam pressure, easy to dissolve in water and easy to reduce is formed between a brominating agent and metal ions; the cleaning treatment of the retired nuclear graphite and the resource recovery of radioactive metal elements are realized.

This invention discloses a wear-resistant dry-coupled probe device for nuclear graphite detection, relating to the field of dry-coupled probe technology. It includes a probe housing with a measurement window at one end. An elastomer core and an ultrasonic transducer assembly are housed within the probe housing, with the elastomer core positioned closer to the measurement window than the ultrasonic transducer assembly. A protective film is detachably connected to the measurement window. This invention adds a detachable protective film to the outside of the elastomer core. During actual testing, the elastomer core contacts the material being tested through the protective film, preventing wear on the elastomer core and thus improving the device's lifespan and detection accuracy.

The application discloses a preparation method of modified high-carbon ferrochrome and belongs to the technical field of nano modification. The method comprises the following steps: ultrasonic dispersion and heating stirring of Fe-Cr alloy powder, nano carbon material, nitrogen source precursor and nano ceramic particles in an alcohol solvent, sintering, hydrofluoric acid etching to obtain core-shell particles; mechanical stirring of the core-shell particles into a high-carbon ferrochrome matrix, followed by addition of graphene powder for smelting to obtain a modified melt; pouring of the modified melt and directional solidification to obtain a modified casting; immersion of the casting into a hexamethylenetetramine ethanol solution, pyrolysis treatment and laser remelting to form a surface wear-resistant layer; quenching and tempering treatment of the casting to obtain a modified casting with a surface nanocrystalline structure. The application remarkably improves the comprehensive performance of the high-carbon ferrochrome through nano heterogeneous nucleation, graphene reinforcement and surface nanocrystallization synergistic modification.