100 results about "Radiation resistant" patented technology

The invention relates to the technical field of photovoltaic adhesive films, and discloses an anti-radiation photovoltaic packaging adhesive film, a preparation method thereof and a photovoltaic module. The adhesive film is of a multi-layer co-extrusion composite structure formed by co-extrusion molding and irradiation, and comprises an upper surface layer, a middle functional layer and a lower surface layer, the upper surface layer is a radiation-resistant polymer matrix (such as EVA-g-St, EVA-g-(alpha-MeSt), POE-g-St and an EVA / POE-aromatic resin blend); the middle functional layer comprises a packaging resin matrix, an anti-radiation agent (which is a nano-scale radiation protection material such as a rare earth oxide, a heavy metal oxide, a boron-containing compound and a polymer derivative of a benzotriazole type ultraviolet absorbent) and a stabilizer; and the lower surface layer is a bonding surface layer formed by light-transmitting bonding resin. The adhesive film is good in radiation resistance, the light transmittance, the cohesiveness, the elongation at break retention rate, the yellowing resistance, the power attenuation resistance of a component and the like after accelerated radiation are obviously improved, and the service life of the component under strong radiation can be prolonged.

The environment-friendly nuclear power high-voltage power cable comprises a cable body, and the cable body comprises a conductor, a semi-conductive shielding layer, an insulating layer, a filling layer, a belting layer, a waterproof layer, an armor layer and an outer protective layer from inside to outside in sequence; the semi-conductive shielding layer is made of a low-smoke halogen-free cross-linked polyolefin semi-conductive material; the insulating layer is made of a radiation-resistant low-smoke halogen-free cross-linked polyolefin composite material; the filling layer is a low-smoke halogen-free polypropylene filling rope; the belting layer is made of a low-smoke halogen-free polypropylene and water-based butyl rubber composite material; the semi-conductive shielding layer tightly wraps the outer side of the conductor, the semi-conductive shielding layer is made of a low-smoke halogen-free cross-linked polyolefin semi-conductive material, is used for uniformizing an electric field on the surface of the conductive wire core and preventing point discharge, and is firmly bonded with the adjacent insulating layer, and the insulating layer is made of a radiation-resistant low-smoke halogen-free cross-linked polyolefin composite material, so that the radiation-resistant low-smoke halogen-free cross-linked polyolefin semi-conductive material has good radiation resistance. And the arrangement of the filling layer, the belting layer and the outer sheath layer improves the comprehensive performance of the cable body and meets the halogen-free, low-smoke, low-toxicity and environment-friendly requirements of the cable.

The invention relates to the field of nuclear cable manufacturing, in particular to a radiation-resistant cable for a nuclear power platform and a preparation method of the radiation-resistant cable. According to the nuclear cable, the five-layer structural design of conductor-insulation-shielding-polyimide film-sheath is adopted, the overlapping wrapping technology of the polyimide film is combined, and the comprehensive performance of the cable in the extreme environment of a nuclear power platform is comprehensively improved. The low-smoke halogen-free flame-retardant ethylene-propylene rubber is adopted as an insulating material, and through the cooperation of an EPDM / POE blending system and the ternary composite flame retardant, the insulating property is stable under the condition of ensuring radiation, and the flame retardant property is excellent. The sheath material is added with the intumescent flame retardant and the polysilazane modifier, so that the cable has no crack at the low temperature of-40 DEG C, the bending radius can be controlled to be less than 5 times of the outer diameter, and the cable is adaptive to the layout of a narrow cabin. Through the synergistic effect of material innovation and structural design, the balance of flame retardant property, mechanical property, radiation resistance, low temperature resistance, aging resistance and small-space applicability of the nuclear cable is realized.

The utility model discloses a kind of irradiation resistance underwater light supplementing lamps, belong to underwater light supplementing lamp technical field, solve the irradiation range of the underwater light supplementing lamp of multiple lamp body becomes larger, but condensing effect is obviously worse, so cannot condensing clear irradiation certain object, affect the visibility when actual underwater operation problem. Including circular arc lamp panel, the lamp body of several fixed connections in lamp panel, and the light-reflecting plate of the rotation connection in lamp panel outer circle, several light-reflecting plate can be relative lamp panel flip, several light-reflecting plate synchronous rotation setting. The utility model uses, when needing large range illumination, traction electromagnet pulls connection rope, makes light-reflecting plate deflect, torsional spring accumulates elastic potential energy, turns wire pole and prevents connection rope scratch breakage. When needing condensing irradiation, traction electromagnet is powered off, release connection rope, torsional spring releases potential energy and drives light-reflecting plate reverse deflection, forms spotlight cover, makes light concentration, clear irradiation object, does not affect underwater operation visibility.

The invention relates to the technical field of thermal control coatings, in particular to a liquid metal commercial aerospace thermal control coating adaptive to extreme temperature difference, which comprises a substrate binding layer and a thermal control functional layer, the thermal control functional layer is arranged on the side wall of the substrate binding layer, a thermal circulation pipe is arranged in the thermal control functional layer, and a composite heat conduction layer is arranged on the side wall of the thermal control functional layer. A limiting stabilizing layer is arranged on the side wall of the composite heat-conducting layer. By arranging the multi-layer composite structure and the liquid metal, efficient heat regulation and control in an extreme temperature difference environment are achieved, the substrate combination layer is made of a radiation-resistant material, it is ensured that the structure stability is kept in a strong radiation environment, the liquid metal material in the heat control function layer and a cross circulation plate form a three-dimensional heat conduction network through a disc-shaped heat control circulation pipe, and the heat conduction efficiency is improved. And by arranging the separation cavity, atomic oxygen erosion is effectively blocked, and the inorganic thermal control coating layer of the separation cavity can adjust the surface thermal radiation characteristic.

The invention relates to the technical field of cables, in particular to a self-checking acid and alkali resistant nuclear cable which comprises conductors, double-layer insulation, a polyimide tape layer, a filling layer, a waterproof inner sheath and an outer sheath. The waterproof inner sheath and the waterproof outer sheath are made of acid and alkali resistant fluororubber materials, and can cope with long-term soaking of strong acid and alkali solutions under extreme accidents of a nuclear power station; through the combined design of double-layer insulation and the polyimide tape layer, the radiation resistance, high temperature resistance and flame retardance of the cable are improved, and the special working condition requirements of the nuclear power station are met; through the synergistic effect of the built-in diversion monitoring pipe, the external diversion monitoring pipe and the magnetic control reciprocating diversion pump, in cooperation with the temperature and humidity sensor and the pressure sensor, temperature, humidity and pressure state parameters in the cable can be monitored in real time, so that the running state of the cable is judged, the internal heat dissipation effect of the cable is enhanced, and when the parameters exceed a preset threshold value, the cable is protected. Early warning signals can be sent to an external monitoring terminal in time, so that workers can check hidden dangers in time, and the maintenance cost is reduced.

This invention relates to the field of neutron dose monitoring, specifically to a method and apparatus for monitoring the dose equivalent around neutrons over a wide energy range. The apparatus includes an outer moderator, a thermal neutron absorbing layer, a high-energy neutron compensation layer, and an inner moderator. The high-energy neutron compensation layer is composed of a heavy metal material capable of undergoing a significant neutron multiplication reaction with ultra-high-energy neutrons. The thermal neutron detector is a radiation-resistant solid-state semiconductor detector, comprising a silicon carbide semiconductor substrate and an enrichment layer closely adhering to its surface. 6 The device is equipped with a lithium fluoride thermal neutron converter; an initial thermal neutron detector group is deployed within the device to collect thermal neutron fluence information under different slowing degrees; based on the initial thermal neutron detector group, position optimization and weight coefficient output are performed, and multiple groups of thermal neutron detectors in the first depth order are selected to make the total dose response flat in a wide energy range for dose equivalent monitoring.

The utility model belongs to the technical field of power cables, and particularly relates to an IE-grade K3-class radiation-resistant power cable, which comprises a protective sleeve, ventilation and heat dissipation ports arranged at equal intervals are arranged on the outer surface of the protective sleeve, a connecting sleeve is arranged in the protective sleeve, a power cable is arranged on the inner wall of the connecting sleeve, and two groups of support rings are fixedly connected to the outer surface of the connecting sleeve. The side faces, close to each other, of each set of supporting rings are fixedly connected with supporting plates arranged at equal intervals, the side face, away from the connecting sleeve, of each supporting plate is fixedly connected with two sets of telescopic springs, and the ends, away from each other, of each set of telescopic springs are fixedly connected with connecting plates. Particularly, an elastic buffering system composed of a supporting ring, a supporting plate, a telescopic spring and a connecting plate can convert mechanical impact into spring deformation energy, the external force resisting performance is greatly improved, and meanwhile an efficient heat dissipation path can be formed by matching equidistant ventilation heat dissipation openings in the surface of the protective sleeve with an air channel between the protective sleeve and a connecting sleeve.

The invention relates to the technical field of nuclear energy fuel cladding materials, in particular to a nuclear high-temperature-resistant and radiation-resistant ODS ferrite alloy and a preparation method of a pipe of the nuclear high-temperature-resistant and radiation-resistant ODS ferrite alloy. The ODS ferrite alloy comprises the following components in percentage by mass: 11.0 to 15.0 percent of Cr, 1.0 to 3.0 percent of W, 0.1 to 1.0 percent of Mn, 0.0 to 0.6 percent of Ta, 0.2 to 0.6 percent of Ti, 0.15 to 0.5 percent of Y, 0.11 to 0.26 percent of O and Clt, 0.1%, Zirt; %, 0.01%, Allt; the mass ratio of Y to Ti is equal to 0.4-1.0, and the pipe is prepared by adopting the processes of hot forging, low-temperature quick forging and room-temperature rolling. The ODS ferrite alloy and the pipe thereof provided by the invention have a microstructure with fine grains and uniformly distributed nano oxides, the alloy and the pipe have excellent high-temperature mechanical properties, the quality of the inner surface and the outer surface of the pipe is good, and the linear precision is high.

A hoisting plate is fixedly connected with a boss through a net plate to form a hoisting frame, the two hoisting frames are fixedly connected together through two bridge frames to form the damping frame, the hoisting plate, the bridge frames, a supporting table, the boss and the net plate are all made of Q355B steel, the thickness of the supporting table is 20 mm, the thickness of the supporting table is 20 mm, and the thickness of the boss is 20 mm. The thickness of the hoisting plate is 8mm, the thickness of the net plate is 6mm, and the thicknesses of the bridge frame and other plates are 5mm; the net plate and the hoisting plate are provided with cross-shaped reinforcing ribs with the width of 5 mm and the height of 8 mm, and triangular reinforcing ribs with the thickness of 5 mm are arranged on the rack main body; lightening holes are formed in a web plate of the screen plate; the boss is matched with the supporting table in a convex-concave structure, and the polyurethane pouring layer is filled in a convex-concave gap between the boss and the supporting table to form an anti-falling structure. The vibration isolator can effectively reduce impact stress, and has the characteristics of good vibration isolation effect, irradiation resistance, corrosion resistance, light weight, high strength and the like.

The utility model relates to the technical field of film heaters, in particular to an irradiation-resistant heater, which comprises an electric heating layer, a pair of leads and a pair of insulating layers. The electric heating layer is fixedly arranged between the pair of insulating layers; the head ends of the pair of wires are electrically connected with the positive electrode of the electric heating layer and the negative electrode of the electric heating layer respectively. According to the utility model, the thermoplastic connecting layer made of the thermoplastic polyimide material is adopted to replace a bonding layer of a film heater in the prior art, so that the total radiation-resistant dose of the device is improved to 1.0 * 1010rad (SI), and the device can meet the requirements of the use environment outside a spacecraft cabin; the defect that a film heater in the prior art is poor in environment adaptability is overcome.

The application relates to a glass for liquid scintillation capillary array and a preparation method and application thereof. The glass components in terms of mole percentage include: 80-85% of SiO2; 0.5-4% of Al2O3; 4.5-8% of B2O3; the sum of K2O and Na2O is 2-8%; the sum of PbO and CdO is 1-2%; 1.5-4% of ZrO2; the sum of KFH2 and K2SiF6 is 1-4%; 0.2-0.5% of BaF2; and 0.5-1% of CeO2. The technical problem solved is how to provide a glass with low refractive index, high softening point, good anti-crystallization performance, good pressure resistance and radiation resistance, so that the glass can be used for preparing a liquid scintillation capillary array.

The utility model provides an anti-contamination instrument water filling and air exhausting tool which comprises an equipment body, a lower sealing component, an upper sealing component and a drainage pipeline, a pipeline channel is formed in one end of the equipment body, and the lower sealing component and the upper sealing component are connected to the two ends of the pipeline channel of the equipment body respectively. The drainage pipeline is connected to the upper sealing component and communicated with the pipeline channel of the equipment body, and the pipeline channel of the equipment body is connected with the instrument water filling and exhausting connector through the lower sealing component. According to the utility model, the equipment main body made of a radiation-resistant material and the built-in rotating ratchet wheel are matched with the instrument pollution discharge plug, and are matched with the two built-in sliding sealing rings in the lower sealing part to be connected with the instrument pollution discharge port, so that the radioactive medium is drained, and the pressurized radioactive medium can be effectively prevented from splashing; the safety problem caused by the fact that radioactive media in a pipeline splash or flow out when a traditional water filling and air exhausting tool such as an open spanner is used for instrument water filling and air exhausting is solved.

This application discloses a radiation-resistant glass, a chemically strengthened glass, and their preparation methods and applications, belonging to the field of glass material technology. The radiation-resistant glass, based on the mass percentage of oxides, comprises: SiO2: 64.0~72.0%, Al2O3: 1.0~7.0%, MgO: 1.0~2.0%, ZnO: 2.0~5.0%, Na2O: 5.0~9.0%, K2O: 3.0~5.5%, CaO: 0.1~2.0%, B2O3: 0~6.0%, TiO2: 0~3.0%, CeO2: 2.0~6.0%, Sb2O3: 0.01~2.0%; and satisfies: 1.5≤(B2O3+Na2O) / (Al2O3+ZrO2)≤5; 1.70≤Na2O / K2O≤1.80; 0≤TiO2 / CeO2≤1.0. This application enables the glass to possess excellent radiation resistance and optical stability, low coefficient of thermal expansion, high strength and safe breakage characteristics by adjusting the basic components and proportions. It can be used in applications that require ultraviolet cutoff and resistance to high-energy radiation, such as in solar modules, as a cover plate for solar modules in aerospace or outer space environments.

The utility model relates to the technical field of intelligent cards, and discloses an anti-radiation intelligent card, which comprises an intelligent card bottom plate, the upper end of the intelligent card bottom plate is fixedly provided with a mounting groove, the upper end of the mounting groove is fixedly provided with an induction ring, one end of the induction ring is fixedly provided with a connection data line, and the other end of the induction ring is fixedly provided with a power supply. A fixing clamping groove is fixedly formed in one end of the connecting data line, a card recognition plate is fixedly arranged at the upper end of the interior of the fixing clamping groove, a clamping structure is fixedly arranged at the upper end of the mounting groove, and a protection structure is fixedly arranged at the upper end of the intelligent card bottom plate. According to the anti-radiation intelligent card, through the improvement of the intelligent card, the clamping and protection capability of the intelligent card is improved, in the actual use process of the intelligent card, the SIM card can be effectively fixed and clamped according to needs, the protection and radiation resistance of the intelligent card are facilitated, and the use experience of the anti-radiation intelligent card is improved.

A nuclear-grade radiation-resistant infrared video monitoring system belongs to the technical field of nuclear facility safety monitoring, and comprises a radiation-resistant infrared camera used for collecting infrared video data in a strong nuclear radiation environment; the image processing unit is used for performing enhancement processing on the infrared video data, removing non-uniform fixed mode noise caused by radiation and obtaining an enhanced video image; and the intelligent analysis and prediction unit is used for carrying out quantitative identification on the enhanced video image, obtaining pipeline defects in the video image and carrying out risk prediction. The problems that no available infrared monitoring equipment exists in a radiation area of an existing nuclear facility, the existing nuclear facility depends on an imported visible light camera (the problems of short service life, sensitivity to temperature, poor image quality and the like), and the existing nuclear facility lacks intelligent early warning capability are solved.

The utility model discloses a radiation-resistant long-life low-noise coaxial cable for a nuclear power station, which comprises a conductor formed by twisting tinned soft copper, and a wrapping semi-conductive layer, an insulating layer, an extruded semi-conductive layer, a comprehensive shielding structure, a wrapping high-temperature-resistant layer and an outer sheath are sequentially arranged outside the conductor. The tinned soft copper conductors are stranded, so that the structural stability is ensured, and oxidation is avoided; the insulating layer is made of radiation-resistant and long-service-life crosslinked polyethylene, so that the transmission performance is ensured to be stable; noise is reduced through the semi-conductive layer, and signal quality is improved; a comprehensive shielding structure is adopted, so that the electromagnetic compatibility is enhanced; the high-temperature-resistant layer is arranged to meet the high-temperature requirement of the And the outer sheath is made of a radiation-resistant polyolefin material, so that the mechanical property and the service life are ensured. Overall performance is excellent, and the system is suitable for complex environments.

The invention discloses a high-temperature and vibration coupled soft sealing structure, which is used for a high-temperature vibration sensor calibration device and comprises a base, an outer corrugated pipe, an inner thermal radiation shielding layer and a fixed mounting block, the corrugated pipe and the thermal radiation shielding layer are of symmetrical cylindrical hollow metal structures, and the thermal radiation shielding layer is arranged on the inner side of the corrugated pipe. The fixed mounting block is a cylindrical metal mounting block, the base is of a symmetrical cylindrical hollow metal structure, the upper end of the corrugated pipe and the upper end of the heat radiation shielding layer are connected with the fixed mounting block, the lower end of the corrugated pipe is welded and fixed to the base, and a plurality of through holes are formed in the fixed mounting block and the base respectively. The connecting piece is fixedly connected with the high-temperature vibration sensor calibration device through a screw; the corrugated pipe, the base and the fixed mounting block are made of high-temperature-resistant metal materials, the corrugated pipe is formed by welding thin metal plates in a corrugated shape, and the inner thermal radiation shielding layer is made of thermal radiation prevention metal materials. According to the invention, heat leakage can be reduced, the uniformity of a temperature field is improved, and the calibration precision is improved.

A space active optical cable (SAOC) includes a cable including one or more optical fibers, and two or more electrical transceivers on opposing ends of the cable and interconnected by the cable. Each of the electrical transceivers includes an enclosure that encloses one or more light sources, one or more light detectors, and control electronics. Also included in the enclosure are a coupling medium to couple light into and out of the one or more optical fibers. The coupling medium can be reflecting surface or an on-axis mount. The enclosure provides a suitable heat propagation and electromagnetic interference (EMI) shielding, and the cable and the two or more electrical transceivers are radiation resistant. SAOC features optionally support a health check algorithm that allows trending optical performance in the absence of an optical connector and a potential surface treatment to increase nominally low emissivity of an EMI conductive surface.

The application discloses an anti-radiation sensor, which comprises a sensor body, a base fixedly connected to the bottom of the sensor body, and a sensing surface on the top of the sensor body; and an anti-radiation assembly surrounding the side surface of the sensor body, which comprises, from inside to outside, a heat insulation layer, an anti-radiation layer and a protective shell. The application provides an anti-radiation sensor, which can reduce the influence of external radiation on the sensor by arranging the anti-radiation assembly outside the sensor body, so that the sensor can normally work in a high-dose-rate and high-cumulative-dose radiation environment, and stable operation of the sensor is ensured.

The application discloses a kind of high-temperature high-pressure thermal flow sensor of radiation resistance and preparation method thereof, and relates to the technical field of sensor.The purpose of the present application is to solve the problems of low precision, large error, complex process preparation, high cost and long production cycle in the preparation process of traditional thermal flow sensor.The present application is based on ceramic co-firing process technology, and the main process includes punching process, screen printing process, laminating process, cutting process and glue sintering process, etc.The preparation of flow sensor of different flow rates is realized through electrode material system, structure design and debugging calibration.The manufacturing method of the present application can reduce temperature gradient and improve heat exchange efficiency, improve precision and service life, and meet the specific environmental requirements of high temperature, high pressure and radiation.The present application can obtain a kind of high-temperature high-pressure thermal flow sensor of radiation resistance and preparation method thereof.

The invention provides a space-environment-resistant flexible solar cell array and a preparation method thereof, and relates to a cell and a manufacturing method thereof, the space-environment-resistant flexible solar cell array comprises a flexible substrate, a thin film solar cell and a flexible transparent radiation-resistant packaging film which are stacked and fixed from bottom to top; the flexible transparent radiation-resistant packaging film completely covers the thin film solar cell; the flexible transparent radiation-resistant packaging film is a pseudo glass sheet which is prepared by uniformly mixing and curing glass beads and cover sheet glue; the glass beads are at least one of cerium-containing glass beads, titanium dioxide hollow glass beads, samarium-doped borosilicate glass beads and indium tin oxide (ITO) modified glass beads; the particle size of the glass beads is less than or equal to 38 microns; the mixing ratio of the glass beads to the cover sheet glue is 1: (0.5-4).

The application discloses a novel resistive material applied to a microstructure gas detector and relates to the technical field of composite materials, which comprises an insulating base layer and a high-conductivity material outer layer, wherein the high-conductivity material outer layer is composed of a conductive polymer and nanoscale conductive material after modification; a microstructure layer is further arranged on the outer surface of the high-conductivity material outer layer; and a self-repairing structure is further arranged in the high-conductivity material outer layer, wherein the self-repairing structure comprises a plurality of microcapsules uniformly embedded in the high-conductivity material outer layer. The novel resistive material applied to the microstructure gas detector disclosed by the application significantly improves the detection sensitivity and time resolution of the microstructure gas detector, has excellent radiation resistance and environmental adaptability, and solves many defects in the prior art. Through microstructure design and self-repairing function, the material exhibits excellent performance under high particle flow conditions and is suitable for application in the fields of high-energy physics and nuclear medicine.

The application relates to the technical field of photovoltaic adhesive films, and discloses an anti-radiation photovoltaic packaging adhesive film, a preparation method thereof and a photovoltaic module. The adhesive film is a multilayer co-extrusion composite structure formed through co-extrusion molding and irradiation, and comprises an upper surface layer, a middle functional layer and a lower surface layer; the upper surface layer is a radiation-resistant polymer matrix (such as EVA-g-St, EVA-g-(alpha-MeSt), POE-g-St or an EVA / POE-aromatic resin blend); the middle functional layer comprises a packaging resin matrix, an anti-radiation agent (a nanoscale radiation protection material such as a rare earth oxide, a heavy metal oxide, a boron-containing compound or a high molecular derivative of a benzotriazole type ultraviolet absorber) and a stabilizer; and the lower surface layer is a bonding surface layer formed by a light-transmitting bonding resin. The adhesive film has good radiation resistance, and the light transmittance, bonding property, elongation at break retention rate, yellowing resistance and module power attenuation resistance of the adhesive film after accelerated irradiation are obviously improved, so that the service life of the module under strong radiation can be prolonged.

The invention discloses an anti-radiation large-current SiC device packaging structure, and belongs to the technical field of power semiconductor packaging. The module comprises at least two subunit modules, a miniature common mode inductor, an interconnection copper column and an annular flow channel radiator. Each subunit module comprises an upper half bridge arm, a lower half bridge arm and a parallel SiC MOSFET chip, a miniature common mode inductor is integrated in a driving loop, an interconnection copper column is connected with the subunit modules, and an annular flow channel radiator is filled with a heat-conducting medium and multiplexed as an irradiation shielding layer. Through the synergistic effect of external shielding and internal suppression, the problems of uneven electric heating and grid oscillation induced by irradiation are solved, large-current transmission, efficient heat dissipation and anti-irradiation performance are considered, the reliability of the device in severe environments such as aerospace and high-altitude power transmission is improved, and the device has important engineering application value.

The present application relates to the technical field of nuclear industry robot control, and discloses a radiation-resistant variable stiffness mechanical arm, comprising a plurality of torsion modules, two adjacent torsion modules are connected through a rotating module, so that the torsion module can spin around its longitudinal axis and rotate around the horizontal axis of the rotating module, the top of the uppermost torsion module is provided with a top cover, the bottom of the lowermost torsion module is provided with a bottom plate, a plurality of SMA artificial muscles are connected between the top cover and the torsion module, between the torsion modules and between the torsion module and the bottom plate, the two ends of the SMA artificial muscle are led out of wires and connected to independent driving circuits. The radiation-resistant variable stiffness mechanical arm can control the stiffness and deformation of the mechanical arm, greatly reduce the volume and weight of the mechanical arm and improve the power density.

The utility model discloses a printed circuit board (PCB) applied to a Birch Stream server, which comprises a PCB body, and the PCB body comprises a copper foil layer I, a polytetrafluoroethylene layer I, a substrate layer, a polytetrafluoroethylene layer II and a copper foil layer II which are arranged in sequence. The PCB further comprises a heat dissipation piece, an installation hole is formed in the PCB body, and the heat dissipation piece is installed in the installation hole. According to the invention, the first polytetrafluoroethylene layer and the second polytetrafluoroethylene layer are arranged, and the excellent high-frequency dielectric property, excellent high and low temperature resistance and excellent radiation resistance of polytetrafluoroethylene are utilized, so that the PCB has the advantages of low dielectric constant, low dielectric loss, high signal fidelity, excellent high and low temperature resistance and excellent radiation resistance; meanwhile, by arranging the heat dissipation piece, the heat dissipation capacity of the PCB can be improved, and therefore the PCB can well meet the application requirement of a Birch Stream server.

This invention belongs to the field of target material processing technology, specifically a radiation-resistant target melting device, including a target melting assembly and a melting tank assembly for holding the target material, secured by the target melting assembly. The target melting assembly includes a base, a heating seat, a tank body support for securing the melting tank assembly, and a drive control unit for driving the melting tank assembly's switch. The melting tank assembly includes a tank body assembly and a tank cover assembly. The tank body assembly is placed on the heating seat and secured by the tank body support. The tank cover assembly is connected to the output end of the drive control unit. The tank body assembly includes a heat-conducting plate, heat-conducting metal strips, and a tank body made of radiation-resistant material. A heat-conducting plate is provided at the bottom of the tank body, and multiple heat-conducting metal strips are connected circumferentially along the edge of the heat-conducting plate. Each heat-conducting metal strip is inserted into the tank body. This invention has good radiation resistance, and combined with the tank body, it effectively isolates external radiation while ensuring uniform heating inside the tank.

The invention discloses a high-temperature-irradiation-resistant inflatable sealing ring for a nuclear power station equipment gate and a preparation method, the sealing ring comprises an integrated hollow inflatable annular sealing body, and the sealing body is sequentially compounded with a high-temperature-irradiation-resistant ethylene propylene diene monomer outer layer, a polyamide fiber woven reinforcement layer and a low-gas-permeation rubber inner layer from outside to inside; the polyamide fiber woven reinforcing layer is of a continuous and joint-free integral woven structure and is bonded with the ethylene propylene diene monomer outer layer and the low-gas-permeation rubber inner layer into a whole through an adhesive. On the basis of a known EPDM + polyamide fiber system, a complete and reliable technical chain from materials to finished products is constructed by introducing a precise split combined mold, a Chemlok 238 adhesive cement pretreatment bonding process and an optimized formula containing an irradiation-resistant auxiliary agent; the problem of early failure caused by material failure, weak structure or insufficient verification of a traditional sealing ring is solved.

The application provides a kind of radiation resistant multimode optical fiber and its preparation method.The application provides a kind of radiation resistant multimode optical fiber, and the radiation resistant multimode optical fiber includes core layer, adjusting layer, fluorine-doped cladding layer and barrier layer and outer cladding layer.Core layer is located in the center of the optical fiber;Adjusting layer is wrapped outside the core layer;Fluorine-doped cladding layer and barrier layer are located outside the adjusting layer;Outer cladding layer is located outside the fluorine-doped cladding layer and the barrier layer.The absolute value of the refractive index difference between the core layer and the adjusting layer relative to the outer cladding layer gradually increases from the center of the core layer to the outside of the adjusting layer;The refractive index difference of the core layer relative to the outer cladding layer is a parabola from its center to its outside, the refractive index difference of the adjusting layer relative to the outer cladding layer is an inclined straight line, and the absolute value of the slope of the inclined straight line is less than the absolute value of the slope of the parabola endpoint.To solve the problem of high-order mode pulse shift caused by the diffusion of fluorine element at the core-cladding interface in the existing radiation resistant multimode optical fiber technology.