40results about How to "Hazard reduction" patented technology

The invention relates to the technical field of disaster prevention and control, in particular to a disaster identification and disposal method based on real-time video information and a knowledge graph. The method comprises the following steps: preprocessing video data of a disaster area to obtain disaster images at all moments; inputting the disaster image at the current moment into the trained first detection model to obtain a first disaster type, a personnel density and disaster duration; inputting the disaster image at the current moment into a trained second detection model, and obtaining personnel behaviors, disaster features, disaster grades and second disaster types; obtaining a current disaster type according to the first disaster type and the second disaster type; and constructing a disaster knowledge graph, and searching an emergency response scheme in the disaster knowledge graph according to the current disaster type, the personnel density, the disaster duration, the personnel behavior, the disaster characteristics and the disaster level. According to the invention, the accuracy and real-time performance of disaster monitoring can be improved, and a corresponding emergency scheme is provided for disaster disposal.

The invention provides a preparation method of a high-expansion phosphoramidated natural polysaccharide flame retardant. The preparation method comprises the following preparation steps: S1, carrying out amination treatment on a phosphoramidated reagent to obtain a precursor solution; and S2, adding the natural polysaccharide into the precursor solution, and carrying out phosphoramidation reaction to obtain the high-expansion phosphoramidated natural polysaccharide flame retardant. According to the invention, the natural biomass is used as the raw material, and the water is used as the solvent, so that the prepared flame retardant has the advantages of high expansion rate, low environmental hazard, high matrix compatibility and excellent flame retardance. Moreover, on one hand, the flame retardant prepared by the invention has higher expansion rate and fire endurance, and on the other hand, the heat released by the flame retardant during combustion can be reduced and inhibited, so that the harm to the environment is reduced, and the practical effect of the flame retardant prepared by the invention during use is further ensured.

The invention relates to a method for removing trace toxic polycyclic aromatic hydrocarbon in coal-based residues, which comprises the following steps of: crushing the residues to obtain residues before modification, and grinding and uniformly mixing the residues before modification and a modifier to obtain mixed powder; adding the mixed powder, a catalyst and a system solvent into a reactor, and carrying out a chemical reaction for removing toxic polycyclic aromatic hydrocarbon; a reaction product is collected and recycled through rotary evaporation, modified residues are obtained after solids are dried and ground, and the solvent is recycled; according to the method, the content of the toxic polycyclic aromatic hydrocarbon in the coal-based residues is reduced to the greatest extent by preferably selecting the multifunctional composite modifier and establishing an efficient removal method of the polycyclic aromatic hydrocarbon, and indexes such as the softening point, the needle penetration and the solubility in the residues are improved; the content of trace toxic polycyclic aromatic hydrocarbon in the coal-based residues can be reduced, the rheological property and stability of the residues are improved, and the pavement standard of road asphalt is met.

The present invention relates to an anti-mite down jacket fabric and a processing method thereof, wherein the anti-mite down jacket fabric comprises an inner layer and an outer layer hot-pressed and composited on the inner layer, wherein the outer layer is a plain fabric woven from cotton fiber, modified viscose fiber, and polylactic acid fiber; wherein the modified viscose fiber is prepared by mixing camel thorn alkaline essential oil and a thickener into viscose, and then heating, stirring, ultrasonically dispersing, and degassing the viscose mixture through a wet spinning process. The present invention adds camel thorn alkaline essential oil to the preparation of the modified viscose fiber, and the camel thorn alkaline essential oil has a strong antibacterial effect on Escherichia coli, Staphylococcus aureus, and Candida albicans, and the camel thorn alkaline essential oil has a strong inhibitory effect on the reproduction of mites, can also expel mites, has good durability, natural ingredients, less harmful to the human body, is safer, and can improve the wrinkle resistance of the anti-mite down jacket fabric.

The invention relates to the technical field of coal crushing devices, and discloses a coal crushing device for a thermal power plant, the coal crushing device comprises a main frame mechanism, the main frame mechanism comprises a crushing box, the crushing box is internally provided with a crushing assembly, the bottom of the crushing assembly is provided with a filtering assembly, and the top of the crushing box is provided with a dust collecting assembly; and the crushing assembly comprises a second motor, the outer surface of the second motor is fixedly connected with a motor support, the right side of the motor support is fixedly connected with the left side of a crushing box, two crushing rollers are arranged in the crushing box, and the interiors of the two crushing rollers are fixedly connected with third rotating shafts. A motor I is started to work to drive a rotating shaft III to rotate, the rotating shaft III rotates to drive two crushing rollers to rotate relatively and crush crushed coal briquettes, and the crushed coal briquettes are crushed again, so that the crushing effect on the coal briquettes is greatly improved, and the practicability of the equipment is greatly improved; and meanwhile, the yield of products is greatly improved.

The invention provides an electromagnetic interference suppression method and device for a PWM signal, electronic equipment and a storage medium, and relates to the technical field of vehicles, and the method comprises the steps: obtaining a PWM signal generated by a drive circuit and an original drive frequency of the PWM signal, the original drive frequency being a higher harmonic frequency corresponding to the PWM signal; at least one first target driving frequency corresponding to the original driving frequency is determined, the first target driving frequency is different from the original driving frequency, the first target driving frequency is any driving frequency in a preset driving range, and the at least one first target driving frequency is not completely the same; and controlling the driving circuit to drive based on the at least one first target driving frequency. According to the invention, the electromagnetic interference of the PWM signal can be effectively suppressed, and the harmfulness of EMI radiation interference is reduced.

The utility model relates to an anti-ice-falling device for the surface of a cross tie beam of a bridge tower, which comprises a plurality of anti-ice-falling devices arranged on the surface of the cross tie beam, each anti-ice-falling device comprises an anti-ice-falling clamp, a plurality of raised fixing pieces and a plurality of extended connecting pieces, and the anti-ice-falling clamps comprise a first anti-ice-falling clamp and a second anti-ice-falling clamp. The first anti-ice-falling clamp and the second anti-ice-falling clamp are fixedly arranged on the edges of the left side and the right side of the cross tie beam respectively, and the first anti-ice-falling clamp and the second anti-ice-falling clamp are connected into a whole through the extending connecting pieces and the protruding fixing pieces and fixed to the upper surface of the cross tie beam. The limiting baffles arranged at certain intervals prevent solid accumulated ice from sliding on the upper surface of the bridge tower cross tie beam, meanwhile, lateral drainage of the upper surface of the cross tie beam cannot be hindered, the phenomenon that a traditional drainage channel becomes a'water blocking channel 'due to icing is avoided, and the size of a single block of ice accumulated on the upper surface of the cross tie beam is limited within a safety threshold value as much as possible.

This application discloses a soft magnetic powder composite, a magnetic powder core material, and an insulating coating method based on organic growth, belonging to the field of soft magnetic materials technology. The soft magnetic powder composite of this application includes soft magnetic powder and an insulating coating layer, with the insulating coating layer encapsulating the soft magnetic powder. The insulating coating layer is prepared by a crosslinking reaction of dopamine hydrochloride (hereinafter referred to as dopamine) and polyethyleneimine. The soft magnetic powder is selected from metals and / or alloys containing Fe. The insulating coating method of this application has low hazard, achieves high stability within a certain temperature range, features scalable and controllable insulating film thickness, high film uniformity, and effectively isolates interparticle eddy currents. Simultaneously, the insulating coating layer has strong adhesion, reducing the amount of insulating adhesive used, facilitating molding, reducing the dilution effect of non-magnetic phases, and further improving the magnetic properties of the matrix.

The invention discloses a mineral water ozone treatment box with a self-adaptive water volume, and relates to the field of mineral water ozone treatment.The mineral water ozone treatment box comprises a treatment box main body, a mineral water injection opening is formed in the outer wall of the treatment box main body, supporting frames are circularly distributed and fixedly connected to the bottom end of the treatment box main body, and a mounting placement plate is fixedly connected to the interior of the treatment box main body; a control assembly is arranged in the treatment box main body, and an adjusting assembly is arranged in the treatment box main body; according to the device, by arranging a shaking plate, when mineral water in the treatment box main body contains excessive ozone, a transmission ball is started to drive the shaking plate to shake, so that medicine powder and water are uniformly mixed in a rotary spraying ball through shaking, and the mixed medicine liquid is injected into the mineral water in the treatment box main body along with shaking; ozone in mineral water is removed, it is ensured that the water quality is kept in a good state, the water is clearer and purer, and the original taste of the water can be restored.

The invention relates to a low-temperature waste heat blackening agent, a blackening film layer and a manufacturing method. The low-temperature waste heat blackening agent comprises the following components: 24-48% of a water-based acrylic resin dispersion, 4-8% of amino resin, 0.4-4% of a titanic acid compound coupling agent, 0.5-6% of a coloring agent, 0.6-5% of a wetting agent, 0.1-1% of a defoaming agent and the balance of water. The water-based acrylic resin dispersion is used as a film-forming agent of the waste heat blackening agent, amino resin and a titanic acid compound coupling agent are introduced, the crosslinking temperature is reduced, the binding force of a workpiece and a film layer is improved, and the prepared blackening liquid has the characteristics of high dryness, low crosslinking temperature, good film layer glossiness and the like.

This invention discloses a composite dewatering agent for sludge dewatering in wastewater treatment and its preparation method, belonging to the field of sludge treatment technology. The composite dewatering agent comprises, by weight, the following raw materials: 30-50 parts chitosan-acetylcysteine-modified coal gangue, 20-40 parts cationic starch-modified fly ash fiber, and 1-3 parts nonionic surfactant. The composite dewatering agent of this invention, comprising chitosan-acetylcysteine-modified coal gangue, cationic starch-modified fly ash fiber, and nonionic surfactant, significantly improves the sludge dewatering rate through the synergistic effect of each component, utilizing multiple mechanisms such as charge neutralization, adsorption bridging, and the release of bound water through extracellular polymer destruction. This invention fully utilizes solid waste and natural materials in the preparation of the composite dewatering agent, achieving resource utilization of solid waste while avoiding residual pollution from traditional polyacrylamide flocculants and reducing environmental hazards.

The invention belongs to the technical field of conductive macromolecules, and particularly relates to a preparation method of high-conductivity PEDOT conductive powder. According to the preparation method, the alcohol-water mixed solvent is used for replacing a water solvent in a traditional preparation process, a suspension polymerization process is converted into a solution polymerization process, and the PEDOT conductive powder with excellent performance is obtained under the condition that no auxiliaries are added. The method has the characteristics of high efficiency and energy conservation, and the high-conductivity PEDOT powder is obtained by controlling the reaction raw material proportion and the reaction time at room temperature. Meanwhile, the product prepared by the process is good in stability and high in repeatability. Compared with a mainstream PEDOT commodity in the market at present, the PEDOT powder product has higher conductivity and processability.

This application discloses a system and method for producing cryogenic cooling capacity based on carbon dioxide, belonging to the field of pipeline transportation technology. The system includes: a multi-stage compressor, a first heat exchanger, an absorption chiller, a regenerator, a second heat exchanger, a booster pump, and an expander. By processing the input room-temperature gaseous carbon dioxide through a series of steps, the system can output cryogenic gaseous carbon dioxide that provides cryogenic cooling capacity for the cryogenic distillation process of carbon dioxide. By using this cryogenic carbon dioxide to replace liquid ammonia as a refrigerant, not only is the problem of the difficulty in obtaining cryogenic cooling capacity in the cryogenic distillation process solved, but the hazards are also reduced, making the refrigeration process more energy-efficient and environmentally friendly.

This invention provides an automatic valve body grinding system and method. The grinding system includes a frame, a conveying assembly, a grinding device, a material gripping assembly, and a tilting assembly. The frame is a box structure with a closed accommodating space. The conveying assembly includes a first chain conveyor belt and a second chain conveyor belt, with at least a portion of the conveying assembly located within the frame. The conveying assembly is used to convey the valve body. The grinding device is located within the accommodating space and is used to automatically grind the valve body. At least a portion of the material gripping assembly is connected to the top of the frame and is used to grip the valve body and place it in a designated position. The tilting assembly is located within the accommodating space and is used to tilt the valve body 90 degrees. By setting up the material gripping assembly, tilting assembly, and grinding device, this invention can achieve automatic grinding of the valve body, simultaneously grinding both sides of the valve body, improving grinding efficiency. Placing the grinding process inside the frame improves the safety of equipment use.

This application provides a data processing method, apparatus, and device applied to a terminal device. The method includes: acquiring multiple upper eyelid positions and multiple eye opening areas within a preset time period; adjusting the illumination of a lighting device and / or the display of the terminal device based on the multiple upper eyelid positions and multiple eye opening areas, wherein the lighting device is used to provide ambient lighting to the terminal device. This reduces the harm of the terminal device to the user's eye health.

The invention discloses homogeneous-phase low-toxicity zinc-bromine flow battery electrolyte, and belongs to the field of flow batteries. The electrolyte contains zinc salt, bromine salt, sulfamate and acetate. The zinc-bromine flow battery using the electrolyte can realize high coulombic efficiency and stable long circulation. The electrolyte always exists in a homogeneous form in the charging and discharging process, and oil phase dispersion caused by adding a bromine complexing agent into the traditional zinc-bromine flow is avoided, so that the complexity of a zinc-bromine flow battery system can be reduced. Besides, compared with a traditional zinc-bromine flow battery added with a bromine complexing agent, the zinc-bromine flow battery using the electrolyte has extremely low concentration of elemental bromine and polybromide ions, so that the toxicity can be greatly reduced, and the safety of the zinc-bromine flow battery is improved.

The utility model relates to the technical field of wind turbine generator heavy-duty bearings, and particularly discloses a wind turbine generator heavy-duty bearing lubricating device which comprises a bottom plate and a wind turbine generator heavy-duty bearing body, an oil box is fixedly connected to the surface of the bottom plate, a limiting structure is arranged on the surface of the bottom plate, and the limiting structure comprises a supporting arm. The supporting arm is fixedly connected with the surface of the bottom plate, a servo motor is fixedly connected with the surface of the supporting arm, a lead screw is fixedly connected with the output end of the servo motor, the end, away from the servo motor, of the lead screw is rotationally connected with the surface of the bottom plate, and a driving arm is in threaded connection with the surface of the lead screw. And the surface of the driving arm is fixedly connected with an extension plate, the two sides of the extension plate are rotationally connected with threaded rods, and the surfaces of the threaded rods are in threaded connection with a support. According to the utility model, the problem that the heavy-duty bearing of the wind turbine generator needs to be taken out by hands when being placed in the oil box or taken out is solved.

The utility model belongs to the technical field of medical instruments, and discloses a nuclear magnetic tube cleaning device which comprises a supporting disc, a plurality of water outlet supports are fixedly arranged on the supporting disc, the water outlet supports are used for cleaning the inner wall of a nuclear magnetic tube, and supporting columns are arranged at the two ends of the supporting disc; the connector is connected with a plurality of liquid distribution pipes, and the liquid distribution pipes penetrate through the supporting disc and communicate with the bottom end of the water outlet support; one end of the first infusion tube is communicated with one end of the second infusion tube and then is connected with the connector; wherein the other end of the first infusion tube is inserted into the first washing bottle, and the other end of the second infusion tube is inserted into the second washing bottle; a waste liquid pipe is inserted into the waste liquid barrel, and the waste liquid pipe is in butt joint with the waste liquid outlet; wherein a first pressure pump and a second pressure pump are respectively mounted on the first infusion tube and the second infusion tube; the waste liquid outlet is formed in the edge of the supporting disc and located at the lower edge of the supporting disc; according to the cleaning device, the cleaning efficiency and effect are improved, and meanwhile the problems that the nuclear magnetic tube is broken or cracked due to collision and the like are effectively solved.

The invention belongs to the technical field of conductive macromolecules, and particularly relates to a preparation method of PEDOT conductive powder with controllable conductivity. An ethanol solvent is used for replacing water in a traditional preparation process, a suspension polymerization process is converted into a solution polymerization process, and PEDOT powder with various electrical conductivities is obtained by controlling process conditions under the condition that no auxiliaries are added. The method has the characteristic of controllability, and PEDOT powder with different conductivities can be obtained by controlling process parameters such as reaction temperature, reaction time or oxidant dosage. Meanwhile, the product prepared by the preparation process is good in stability and high in repeatability, and compared with mainstream PEDOT commodities in the market at present, the PEDOT powder product has higher machinability and wider application range.

The utility model relates to the technical field of plastic-coated steel pipe defective product treatment, in particular to plastic-coated steel pipe surface coating removing equipment. According to the technical scheme, the device comprises a cabinet body, a scraping sliding rail and a polishing sliding rail, a fixing frame is fixedly installed on the upper portion in the cabinet body, two sliding rods are fixedly installed on the front side in the fixing frame, two clamping plates are slidably installed on the outer walls of the sliding rods, and rotating motors are fixedly installed on the lower portions of the outer sides of the clamping plates; and the output end of the rotating motor penetrates through the clamping plate and is fixedly provided with a fixed disc. Through the combination of various structures, the device can remove the coating on the surface of the plastic-coated steel pipe in a chemical mode, the chemical mode reduces the harmfulness when the coating of the plastic-coated steel pipe is removed, and the situation that follow-up use is affected is avoided, so that the service life of the plastic-coated steel pipe is prolonged, and the service life of the plastic-coated steel pipe is prolonged. And the equipment can polish and grind the outer wall of the cleaned steel pipe, so that the cleanliness and smoothness of the outer wall of the steel pipe are improved, and a worker can conveniently process the steel pipe subsequently.

This application provides a method for removing aluminum from lithium iron phosphate waste through directional recycling. The method includes the following steps: (1) mixing lithium iron phosphate waste, iron salt solution, and reducing agent to form a slurry, and then reacting in one step to obtain a mixed salt solution containing aluminum ions and ferrous ions, and lithium iron phosphate after aluminum removal; (2) adjusting the pH of the mixed salt solution obtained in step (1), and then reacting in two steps to obtain aluminum hydroxide slag and a solution containing ferrous ions through solid-liquid separation; (3) mixing the ferrous ions obtained in step (2) with an oxidizing agent, adjusting the pH, and then reacting in three steps to obtain an iron salt solution, which is used for recycling the iron salt solution from step (1). The aluminum removal method described in this application does not introduce other impurities during leaching, is simple to operate, pollution-free, and the impurity removal agent can be recycled. Furthermore, the iron element can be recovered, resulting in low process cost and good impurity removal effect.

The present invention belongs to the technical field of floor coating preparation, and specifically refers to a coating preparation device for floor engineering construction, including a base, a preparation tube, a layered mixing mechanism and a negative pumping type gas measuring mechanism, wherein the preparation tube is arranged on the upper wall of the base, the layered mixing mechanism is arranged on the preparation tube, the negative pumping type gas measuring mechanism is arranged on the side wall of the preparation tube, and the layered mixing mechanism includes a pouring mechanism and a stirring mechanism. The present invention provides a coating preparation device for floor engineering construction that can place raw materials of different components in layers to avoid premature mixing and reaction between the raw materials, and can measure the volatile harmful gases released when the raw materials are mixed, timely adjust the raw material components according to the measurement results, and reduce the release of harmful gases in the coating.

The invention relates to the field of solid waste resource utilization, in particular to a coal gangue treatment and processing technological method. The coal gangue treatment and processing technological method comprises the following steps: crushing and grinding coal gangue in sequence to obtain coal gangue powder; the coal gangue powder is subjected to first calcination, and calcined coal gangue is obtained; mixing the calcined coal gangue with a nitric acid solution, and carrying out oxidation treatment to obtain a precipitate; mixing the precipitate, a chemical activator and a solvent, carrying out heat treatment, and carrying out solid-liquid separation to obtain filter residues and filtrate; carrying out secondary calcination on the filter residue to obtain a silicon fertilizer; and adding an acidic leaching solution into the filtrate to adjust the pH value to be acidic, thereby obtaining the humic acid. According to the invention, inorganic matters in the coal gangue are prepared into the silicon fertilizer, and organic matters are prepared into the humic acid, so that combined preparation of the silicon fertilizer and the humic acid is realized, the production cost is greatly reduced, and high value-added utilization of solid wastes is realized.

An electrochemical device is disclosed, including a housing, an electrode assembly, a first bonding piece, and a second bonding piece. The electrode assembly includes electrode plates and a separator. The electrode plates include a first electrode plate and a second electrode plate. The separator is disposed between the first electrode plate and the second electrode plate. The electrode assembly is of a wound structure and located in the housing. In a winding direction, the electrode assembly includes a first section, a first bend section, a second section, and a second bend section that are connected sequentially. An outermost coil of the first section is the separator. The first bonding piece is configured to bond an outermost coil of the electrode plates in the first section together with the separator located outside the outermost coil of the electrode plates in the first section. A bonding force between the first bonding piece and the outermost coil of the electrode plates in the first section is 3 N / m to 30 N / m. The second bonding piece is configured to bond an outermost coil of the separator in the first section together with the housing. A bonding force between the second bonding piece and the housing is 20 N / m to 150 N / m. This application further provides an electronic device containing the electrochemical device. This application can improve the anti-drop performance and safety of the electrochemical device.

The invention discloses an Al Si7Cu0. 5Mg alloy for high-performance casting of an automobile engine and a production process of the Al Si7Cu0. 5Mg alloy, and relates to the technical field of aluminum alloys. The alloy is composed of, by mass, 6.5%-7.5% of silicon, smaller than or equal to 0.15% of iron, 0.48%-0.55% of copper, 0.05%-0.10% of manganese, 0.37%-0.45% of magnesium, 0.10%-0.15% of titanium, 0.015%-0.020% of strontium, smaller than or equal to 0.07% of zinc and the balance aluminum, and impurities contained in the alloy are smaller than 0.3%. The content of the element magnesium is reduced, and the harmful effect of the element magnesium on the toughness and thermal stability of the alloy is reduced; the content of silicon is adjusted, and the casting performance and the cutting performance of the alloy are improved; through strontium modification, the alloy has high density, and the strength and toughness of the alloy are improved; by adding the titanium element, the alloy strength and the higher high-temperature-resistant effect are improved, and an alloy ingot prepared from the alloy has excellent casting performance, mechanical performance, physical performance, corrosion resistance and machining performance; the production process is simple, the process is simple and efficient, and mass production is facilitated.

The utility model relates to the technical field of batteries, and discloses a battery and a power utilization device, and the battery comprises a box body, an outer cover plate, a battery cell group, an inner cover plate and a pressure relief piece. The battery cell groups are arranged in the accommodating cavity along the second direction, each battery cell group comprises a plurality of battery cells arranged along the first direction, and each battery cell is provided with an anti-explosion valve; the inner cover plate is arranged in the accommodating cavity and is connected with one surface, facing the battery cell group, of the outer cover plate, the inner cover plate comprises a plurality of first pressure relief parts extending along the first direction, and the first pressure relief parts are arranged in the accommodating cavity along the second direction; a first pressure relief channel is arranged between each first pressure relief part and the outer cover plate, and the anti-explosion valve of each battery cell is arranged on one surface, opposite to the first pressure relief part, of the battery cell; and a plurality of first pressure relief holes sealed by pressure relief pieces are formed in the positions, opposite to the anti-explosion valve, of the first pressure relief parts. Diffusion of high-pressure gas and eruptions in the battery can be reduced, and the risk of thermal runaway propagation is reduced.

The invention relates to a secondary battery and an apparatus. The secondary battery comprises a positive pole piece, a negative pole piece and an electrolyte, wherein the positive pole piece comprises a positive active material selected from lithium-nickel transition metal oxides; the electrolyte comprises a solvent and a lithium salt, wherein the solvent comprises non-fluoro carbonate, fluoro carbonate and a cyclic sulfone compound; relative to every 100g of nickel element in the positive electrode active material, the content of the cyclic sulfone compound is Ag; relative to every 100g of nickel element in the positive electrode active material, the content of the fluoro-carbonic ester is Bg; wherein 0.1 < = A < = 5, 1 < = B < = 7.5, and 1.3 < = A + 0.25 * B < = 3.3. The electrolyte can effectively improve the problem of high-temperature gas production of the nickel-containing positive electrode battery, improve the out-of-control temperature of a battery hot box, reduce the maximum rate of instantaneous pressure change of a battery combustion bomb, and ensure the normal-temperature cycle capacity retention rate and the high-temperature storage capacity recovery rate of the nickel-containing positive electrode battery.

The present invention discloses a barrel polishing resin grinding block, comprising the following components in parts by weight: 48-57 parts of E-44 epoxy resin, 12-17 parts of curing agent, 3-5 parts of diluent, 21-35 parts of brown corundum powder, 0.5-2 parts of dispersant, and 0.5-2 parts of anhydrous ethanol. The present invention also discloses a method for preparing a barrel polishing resin grinding block, wherein E-44 epoxy resin, diluent, dispersant, and anhydrous ethanol are added to a vacuum stirring tank and mixed evenly; brown corundum powder is added to the base material of the vacuum stirring tank, and the stirring tank is vacuumized and mixed evenly; the mixture is poured into a high-speed stirring barrel, a curing agent is added, and stirred evenly; the finished material is poured into a mold for scraping; the cured blank is demoulded, and dried at 90°C for 4-6 hours to obtain a grinding block. The present invention adopts the above-mentioned barrel polishing resin grinding block and its preparation method, which can solve the problems of the existing grinding block having a large odor, easily generating toxic gases, difficult wastewater treatment, weak cutting force, and a large wear rate.

The invention provides an automatic valve body grinding system and method, the grinding system comprises a frame, a conveying assembly, a grinding device, a grabbing assembly and an overturning assembly, and the frame is of a box body structure with a closed containing space; the conveying assembly comprises a first chain plate conveying belt and a second chain plate conveying belt, at least one part of the conveying assembly is located in the frame, and the conveying assembly is used for conveying the valve body; the grinding device is located in the containing space and used for automatically grinding the valve body. At least one part of the material grabbing assembly is connected with the top of the frame, and the material grabbing assembly is used for grabbing the valve body and placing the valve body at a designated position; the overturning assembly is located in the containing space and used for overturning the valve body by 90 degrees. By arranging the grabbing assembly, the overturning assembly and the grinding device, automatic grinding of the valve body can be achieved, meanwhile, the two faces of the valve body are ground, the grinding efficiency is improved, the grinding process is conducted in the frame, and the use safety of the equipment is improved.

The present invention belongs to the technical field of aviation accessories, and specifically relates to an APU bleed air electric actuator that can be automatically closed, comprising: an electric motor, an electric control mechanism, an bleed air valve, a power-off automatic reset mechanism and a control component. The APU bleed air electric actuator can be automatically closed after power failure at any position to protect the auxiliary power unit (APU) of the aircraft, thereby improving the reliability of the aircraft auxiliary power system and greatly improving flight safety.