130results about How to "Health threat" patented technology

The invention discloses a safety ensuring method of an implantable medical system and a system thereof. The method is characterized by: carrying out encryption function processing to only identification information of an implantable medical device and the only identification information of a corresponding patient controller; writing a generated only cipher lock into the implantable medical device; writing an only secret key into the patient controller after decryption processing is performed to the only cipher lock and the only secret key is generated. Therefore, only can the patient controller possessing the only secret key be communicated with the implantable medical device. When a patient damages or losses the original patient controller, the new patient controller can be configured by using the method of the invention. Even if others get the damaged or lost original patient controller, because the secret key in the original patient controller can not match with the new cipher lock of the implantable medical device, a threat to the health of the patient, which is generated by misusing or maliciously using the patient controller of the other patient, can be prevented.

Pig feed is disclosed. The feed is prepared from following components by weight: 40-50 parts of corn, 30-40 parts of wheat, 15-25 parts of soybean meal, 20-35 parts of sweet potato residue, 2-6 parts of lactic acid bacteria, 3-10 parts of yeast, 10-15 parts of medical stone, 10-15 parts of eggshell, 10-15 parts of shell powder, 20-30 parts of silene conoidea, 10-20 parts of cottonsedge-like thistle herb, 10-15 parts of sweet potato vine, 10-20 parts of purslane herb, 3-10 parts of composite vitamin, 10-25 parts of vegetable oil, 5-15 parts of isatis root, 5-15 parts of liquorice root, 5-15 parts of milkvetch root, 5-15 parts of medicated leaven, 5-15 parts of malt, 5-15 parts of hawthorn fruit and 5-15 parts of dried tangerine peel. The feed is reasonable in formula, comprehensive in nutrition, good in taste and high in feed absorption rate. By adopting a plurality of the proper raw materials and adopting reasonable using amounts, comprehensive nutrition of the feed is optimized, and three functions, namely functions of regulating feed palatability, increasing the lean meat percentage and boosting pig immunity are achieved.

The invention discloses an ecological pesticide and a preparation method thereof. The ecological pesticide is prepared from lantana camara, conical redpepper fruit, onion, pummelo peel and mandarin orange peel, chopping and fully and evenly stirring and bubbling with ethanol or limewater. The ecological pesticide is easy to degrade, has no residual toxity and no threat to the human health, does not harm natural enemy and pollute the environment, has multiple efficacies of desinsection, sterilization, disease prevention and disease resistance, is an ecological pesticide and room pesticide with multiple functions and has simple production process; in addition, raw materials are selected from common waste substances of vegetables and fruits and can be changed into valuables from wastes, so the production cost is low.

The invention discloses a halogen-free and phosphorus-free PBT (polybutylece terephthalate) enhanced composite material and a preparation method thereof, and belongs to the technical field of composite flame-retardant enhanced materials. The halogen-free and phosphorus-free PBT enhanced composite material consists of the following components: 45-65 pats of PBT, 15-30 parts of glass fibers, 15-25 parts of a halogen-free flame retardant, 1-2 parts of a toughening agent, 0.1-0.2 part of a main antioxidant, 0.1-0.2 part of an auxiliary antioxidant, 0.1-1 part of a lubricating agent and 0.3-1.0 part of a nucleating agent. The preparation method comprises the steps of uniformly mixing PBT, the halogen-free flame retardant, the toughening agent, the main antioxidant, the auxiliary antioxidant, the lubricating agent and the nucleating agent according to the weight part to obtain a mixture, and performing melting, coblending and extruding granulation on the mixture and the glass fibers to obtain the halogen-free and phosphorus-free PBT enhanced composite material. The halogen-free and phosphorus-free PBT enhanced composite material prepared by the method is excellent in anti-separation performance, flame retardancy, mechanical property and creepage cracking resistance, does not release hydrogen phosphide poisonous gas and can totally meet a limiting requirement of Samsung on hydrogen phosphide emission concentration.

The invention relates to the technical field of leather and chemical industries, in particular to a silicone-containing amphoteric phosphate fatliquor and a preparation method thereof. The invention aims at providing the silicone-containing amphoteric phosphate fatliquor and the preparation method thereof so as to overcome the problem of affecting the leather color, the physical health of operators and non-ideal fatliquoring effect in the prior art. In order to achieve the purpose, the technical proposal is as follows: the silicone-containing amphoteric phosphate fatliquor is prepared by compounding the following raw materials based on parts by weight: 30-50 parts of polyether-modified polysiloxane phosphobetaine, 20-30 parts of phosphorylated castor oil, 20-40 parts of sulfited fish oil and 0.2-5.0 parts of aliphatic alcohol polyethenoxy ether phosphate. The silicone-containing amphoteric phosphate fatliquor has pale color, does not affect the leather color, has no irritating odor and poses no threat to the physical health of the operators. The fatliquoring leather has the advantages of leather fullness, fine grain surface, elasticity and softness and strong slipperiness; and the fatliquor has good fatliquoring effect.

Described is a system for capturing and removing suspended particles in and from a gas medium. The system comprises a charged assembly (0101), a forced ventilation assembly (0102), a filtering assembly (0103), and a pipeline (0104) allowing gas to pass through and containing the above assemblies. The system is characterized in that the filtering assembly (0103) comprises at least two electrodes with different electric potential differences and a poor conductor fibrous material arranged between the electrodes.

The invention provides a primary and secondary isolation diagnosis table which comprises a diagnosis table body. The inside of the diagnosis table body is provided with a disinfecting and killing system, a fan and an air outlet groove, the air outlet groove is used for forming a doctor and patient isolation air wall and communicated with a working tabletop of the diagnosis table body, an air inletof the fan is used for inhaling outside air, the disinfecting and killing system is communicated with the air inlet of the fan, an air outlet of the fan is communicated with the air outlet groove, the air outlet groove comprises a first groove body and two second groove bodies, the first groove body is parallel to the length direction of the diagnosis table body, the second groove bodies are formed along the width direction of the diagnosis table body and communicated with the first groove body, and vertically telescopic baffle plates are arranged at joints among the first groove body and thesecond groove bodies and used for controlling the first groove body and the second groove bodies to be connected and disconnected. According to the primary and secondary isolation diagnosis table, aerosol exhaled by a patient suffering from an infectious disease can be isolated from medical staff, health of the medical staff can be guaranteed, air channel combination modes can be adjusted according to environmental change, flexible isolation is achieved, and energy consumption is reduced.

The invention discloses a powder falling-resistant hydrophobic nano-aerogel heat-insulating sheet as well as a preparation method and a use method thereof. The preparation method comprises the following steps: step 1) mixing and immersing a glass fiber needled mat with a sol to obtain a sol glass fiber mat precursor; step 2) aging and surface-modifying the sol glass fiber mat precursor to obtain asol fiber mat; step 3) performing supercritical CO2 drying treatment on the sol glass fiber mat to obtain a hydrophobic nano-aerogel heat-insulating material; step 4) performing profile processing onthe hydrophobic nano-aerogel heat-insulating material to obtain a sized hydrophobic nano-aerogel heat-insulating material; and step 5) pasting a film on a surface of the sized hydrophobic nano-aerogel heat-insulating material to obtain the powder falling-resistant hydrophobic nano-aerogel heat-insulating sheet. Compared with a method for attaching a flexible coating to the surface adopted at present, the preparation method provided by the invention has advantages of low cost, high efficiency and simple industry, and well solves popularization and application of aerogel fiber mat products.

The invention provides a novel tensile strength testing device for a core sample. The novel tensile strength testing device comprises a sleeve with a pull board, a test piece fixing sleeve, a gasket and a pulling device, wherein the test piece fixing sleeve comprises a sleeve; the upper part of a sleeve wall of the sleeve is an inner thread part with uniform thickness; the inner thread part gradually becomes thick towards the lower side from the bottom and the section of the inner thread part is in a normal trapezoid shape; the gasket is composed of two semi-circular arc shapes with the same size, the thickness of the gasket is gradually reduced along the vertical direction and the section of the gasket is in a reversed trapezoid shape matched with the normal trapezoid shape of the lower part of the sleeve; the gasket sleeves the two ends of a test piece; after the test piece fixing sleeve sleeves the test piece, the two ends of the test piece are lifted so that the gasket and the test piece fixing sleeve can be mutually engaged to clamp the test piece; the sleeve with the pull board and the inner thread part of the sleeve are in thread connection; one end of the pulling device is hinged with the sleeve with the pull board; and the other end of the pulling device is hinged with a tension tester. With the adoption of the novel tensile strength testing device, preparation and treatment processes of sticking and pulling off the tensile test piece and the pull board, crushing the test piece, stripping off the pull board and the like are simplified, and the working efficiency is improved to the greatest extent.

The invention relates to a nursing pollutant collecting device. The nursing pollutant collecting device comprises a box body, wherein a throwing hole is formed in the middle of the top surface of thebox body; three vertical tubes are uniformly arranged on the lower portion of the inner end of the throwing hole; the vertical tubes are made from transparent plastic materials and are distributed upand down; a transverse partition plate is arranged between gaps of adjacent two vertical tubes; the top surface and the bottom surface of the partition plate are in contact with and matched with the end surface of the corresponding vertical tube, separately; the three vertical tubes are fixedly connected to the inner part of the box body through a first bracket; a first through hole is formed in the upper side of the right end surface of the box body; a first transverse rod is arranged in the first through hole; the inner end of the first transverse rod is fixedly connected to the right end ofthe partition plate on the upper portion; a round leaking hole is formed in a position, close to the left end, of the upper portion of the partition plate; the leaking hole can communicate with the vertical tube; and transverse hydraulic telescopic rods are arranged at the left and right ends of the partition plate on the lower portion. The nursing pollutant collecting device can be helpful for medical staff to finish ultraviolet disinfection of nursing pollutants quickly, and the staff can be fully prevented from being in contact with the pollutants when the pollutants are bagged and tied bythe nursing pollutant collecting device.

The invention particularly relates to a green environmental-protection stemming for a taphole of a submerged arc furnace and a preparation method thereof. The preparation method comprises the steps: firstly, taking 45-65 wt% of bauxite, 5-15 wt% of kyanite, 5-15 wt% of fine quartz powder, 1-3 wt% of fine andalusite powder, 10-30 wt% of alumina micro-powder, 0.5-2 wt% of montmorillonite micro-powder, 1-2 wt% of fine elementary substance silicon powder, 0.5-1 wt% of earthy graphite micro-powder and 1-2 wt% of fine Ti3SiC2 powder as raw materials, then additionally adding 0.05-0.1 wt% of polypropylene fibers, 0.05-0.3 wt% of a retarder, 0.5-2 wt% of ZrOCl2.8H2O and 8-20 wt% of an aluminum dihydrogen phosphate aqueous solution according to the raw materials, wet-grinding for 15-30 min, and then extruding and molding by a mud extruder, and thus obtaining the green environmental-protection stemming for the taphole of the submerged arc furnace. The preparation method has low cost and environmental friendliness, and the prepared green environmental-protection stemming for the taphole of the submerged arc furnace has the advantages of high strength, good volume stability, excellent washing-out resistance, excellent corrosion resistance and repairability for the taphole.

The invention provides an automatic feeding crusher. The automatic feeding crusher comprises a feeding chamber, a crushing chamber and a receiving chamber, the feeding chamber is fixedly connected with the crushing chamber, the crushing chamber is fixedly connected with the receiving chamber, the bottom of the feeding chamber is provided with a feeding hole, the bottom of the crushing chamber is provided with a screen mesh, the center of the top of the crushing chamber is provided with a rotating shaft, the rotating shaft is provided with a blade, the blade is helical in shape and extends from the top of the rotating shaft to the bottom of the rotating shaft, the edge of the screen mesh is provided with an oscillators the center of the screen mesh is provided with a gravity inductor, and the gravity inductor is electrically connected with the feeding hole. The automatic feeding crusher has the advantages of time and labor saving, high safety coefficient, high working efficiency and good crushing effect.

The invention provides a method and a device for evaluating acute toxicity of a liquid fumigation agent to earthworms. The method includes following steps: 1), putting natural soil in a fumigation device; 2), regulating temperature and illumination intensity, and putting multiple earthworms on the surface of the natural soil in the step 1); 3), after all earthworms get into the natural soil, and adding the liquid fumigation agent into the natural soil; sealing the fumigation device, and performing fumigation treatment; 4), investigating death situation of the earthworms, calculating death rate of the earthworms, and evaluating the acute toxicity of the fumigation agent to the earthworms according to the death rate of the earthworms. The method has the advantages of accurate and reliable evaluation results, high repeatability, simplicity, convenience and quickness in operation and safety to operating personnel.

The invention relates to spinel castables for a coal water slurry gasification furnace and a using method thereof. The spinel castables comprise, by weight, 55-72% of magnesium aluminate spinel particles, 0-15% of tabular corundum particles, 4-10% of magnesium aluminate spinel fine powder, 2-5% of magnesium aluminate spinel micro powder, 4-6% of alpha-Al2O3 micro powder, 0.5-1.5% of Y2O3 micro powder, 0.5-1.5% of CeO2 micro powder, 0.2-1% of TiO2 micro powder, 1-7% of pure calcium aluminate cement, 2-12% of CMA cement, 0.03-0.1% anti-explosion fibers, and 0.1-0.3% of FS series water reducer. The using method comprises the steps of pouring water which accounts for 4.8-6.2%, by weight, of the castables in the castables, stirring evenly, and carrying out forming, conservation, demoulding and baking. Products prepared through the spinel castables for the coal water slurry gasification furnace have the advantages of being environmentally friendly, good in coal slag permeation resistance and anti-corrosion performance, capable of saving energy, high in strength and good in thermal shock stability, and thus demands of the production of the coal water slurry gasification furnace are met.

Belonging to the technical field of live poultry breeding, the invention in particular relates to a henhouse feeding device convenient for adjustment of the feeding amount. Directed at the technical problem that an automatic feeding device for free-range chickens cannot crush feed inside a feed bin, the invention proposes the following scheme that: the feeding device includes a storage shell, thetop outer wall of the storage shell is connected to a servo motor through a bolt, and the output end of the servo motor is connected to a rotating shaft through a coupling, one end of the rotating shaft far from the servo motor extends into the storage shell, the circumferential outer wall of the rotating shaft is connected to equally spaced stirring rods through bolts, and the circumferential outer wall bottom of the rotating shaft is connected to equally spaced stirring plates through bolts. According to the invention, the disposed servo motor and stirring rods can mix a variety of feed added into the storage shell, and the arranged stirring plates and cutting blades can achieve crushing treatment on the feed, thereby effectively improving the feed caking situation.

The invention discloses a preparation method of a natural preservative applied to iced fresh duck. The method comprises the following steps: 1) performing pretreatment: segmenting slaughtered Pekin-ducks (about 3.5kg) immediately, selecting duck, cleaning the surface of the duck with sterile pure water to wash off blood and dirt, then segmenting duck breast meat by using a sterile scissor, and then performing freezing storage; 2) preparing a natural preservative: separately preparing a rutin solution with a certain concentration from a rutin biological preservative purchased from the Chengdu Pufei De Biotech Company Limited, and conducting ultrasonic treatment to obtain the natural preservative; 3) performing soaking: soaking the iced fresh duck in the natural preservative, covering the duck with a preservative film, conducting standing and draining; and 4) performing packaging and refrigeration: subjecting the drained iced fresh duck to vacuum packaging by using fresh-keeping bags containing an antibacterial agent, and conducting refrigeration. The method has the advantages that the adopted food preservative is natural plant extract, so the quality of the fresh iced duck can be ensured under the condition, and the bacteriostatic effect is significant.

The invention discloses a multifunctional storage cabinet, which comprises a cabinet body, the cabinet body is a rectangular cavity structure, and an ultraviolet sterilizing lamp is installed on the inner wall of the top plate, and a set of opposite inner walls of the cabinet body are connected with hanging rods. A set of opposite inner walls of the cabinet body is connected with a placement board, and the placement board is located below the hanging rod, an air inlet hole is opened in the middle of the placement board, and drawers are symmetrically installed on both sides of the inner wall of the bottom board of the cabinet body. A hot air blower is fixed on the upper surface of the bottom plate of the cabinet, and the hot air blower is located between two groups of drawers. The air outlet of the hot air blower is connected with a pipe, and the end of the pipe away from the hot air blower is connected with an air inlet. In the present invention, the clothes in the cabinet can be dried, which can effectively prevent the clothes in the wardrobe from being damp for a long time, and the ultraviolet germicidal lamp realizes the disinfection function of the clothes in the cabinet, preventing the clothes from breeding bacteria; and the size of the inner space of the cabinet can be adjusted. Adjustable, easy to place items of various sizes, high applicability.

The invention provides a shower and a water heater with the same. The shower comprises a shower handle, a shower head, a sterilizing lamp member and a water pipe connector, wherein the shower handle comprises a first containing space and a second containing space which are communicated; the shower head is connected on the opening end of the first containing space of the shower handle in a sealed mode, and a water outlet is formed in the shower head; the sterilizing lamp member is placed in the second containing space and comprises an ultraviolet sterilization lamp, and the ultraviolet sterilization conducts sterilization treatment through water in the second containing space; the water pipe connector is connected to the opening end of the second containing space in a sealed mode; By means of the shower in the technical scheme, the problems that in the prior art, a shower cannot meet the human requirements for the safe and healthy shower can be solved.

The invention discloses a float hair removing device for textiles. The device comprises a machine body, a supporting beam, a dust removing pipe, a sponge body and a humidifying plate, a stand column is arranged on one side of the machine body, a water tank is arranged on one side of the stand column, a control panel is arranged above the machine body, the dust removing pipe is arranged at the topof the machine body, the supporting beam is arranged in the machine body, a motor is arranged above the supporting beam, a screw rod is arranged on one side of the motor, a movable block is arranged above the screw rod, and a reinforcing rod is arranged on one side of the movable block. The device has the beneficial effects that the dust removing pipe and the sponge body are arranged, float hair removing is carried out on the surfaces of the textiles twice, in addition, float hair removing can be repeatedly carried out, so that the removal effect is improved, the sponge body and the humidifying plate are arranged, and float hair is collected while float hair removing is carried out, so that the phenomenon that the health of the human body is threatened due to the fact that the float hair enters air can be avoided.

The invention discloses a face protective device for electric welding. The face protective device is used for bringing convenience to electric welding work of an operator. A machine frame and an air pump which are fixedly connected are arranged above guide rails. Rail wheels located on the guide rails are arranged at the bottom of the machine frame and the bottom of the air pump. A lead screw is arranged in the machine frame. The upper portion of the lead screw extends out of the machine frame. A lifting assembly for driving the lead screw to ascend or descend is arranged in the machine frame. A platform is fixed to the upper portion of the lead screw. A base plate is installed on the platform in a hinged mode. A mask is installed at the upper portion of the base plate in a rotary mode. A swinging assembly for driving the base plate to swing in the vertical plane is arranged between the platform and the base plate. A smoke sucking tube and a smoke outlet tube are connected to the air pump. The other end of the smoke sucking tube is fixed to the platform. The other end of the smoke outlet tube extends into a water-contained water tank located above the air pump. By means of the face protective device, the operator does not need to hold the mask with the hands, the double hands of the operator are further released, and a to-be-welded piece is held with the hands. In addition, the angle of the mask can be adjusted to meet the requirements of the operator.

The invention relates to the technical field of printing ink, in particular to a preparation method of water-based flexographic printing ink. The preparation method adopts the following raw materialsin parts by weight: 55-65 parts of water-soluble acrylic resin, 45-50 parts of water-based pigment, 2-4 parts of ethanol, 0.5-1.2 parts of polydimethylsiloxane, 1-1.5 parts of sodium lignin sulfonate,0.3-0.5 part of a defoamer CW-0601, 0.5-1 part of an antibacterial agent, 0.5-1 part of a wax emulsion, 2-3 parts of a triethanolamine buffer agent, 3-5 parts of sodium alginate and 50-60 parts of water. The water-based flexographic printing ink prepared by the method is safe and environment-friendly, and has strong coloring effect, high drying speed, good water resistance and wear resistance, low production cost and good storage stability.

The invention discloses a high-efficiency powder metallurgy dust removal device. The device comprises a shell, the upper surface of the shell is fixedly connected with the lower surface of a dust collector, an air outlet end of the dust collector is communicated with the top end of a guide pipe, the bottom end of the guide pipe penetrates through a pipe sleeve to communicate with the upper surfaceof a first fan cover, and the left side face and the right side face of the first fan cover are fixedly connected with the left side face and the right side face of the inner wall of the shell correspondingly. According to the high-efficiency powder metallurgy dust removal device, the dust collector, the first fan cover, a second fan cover, a filter cover, a baffle, the guide pipe, an adsorptionchamber and a buckling apparatus are matched with one another, when a worker controls the dust collector to work, gas penetrates through the filter cover and enters decomposition liquid in the adsorption chamber through a connecting pipe, dust is retained in the filter cover under the blocking of the filter cover, the filter cover is pulled out of the shell through the baffle, the dust collected in the filter cover is poured out, workers can conveniently recycle the metal dust, and waste of metal resources in the metallurgy process is avoided.

The invention provides a hydrophobic plastic film and a preparation method thereof. The preparation method comprises the following steps of polishing a metal sheet, and cleaning the polished metal sheet; performing sand blasting treatment on the cleaned metal sheet; laminating a plastic plate above the sand-blast metal sheet, and performing stamping treatment; and demolding the stamped plastic plate to obtain the hydrophobic plastic film. The plastic film prepared according to the preparation method has the advantages that the hydrophobicity of the plastic film can be effectively improved, andthe adhesion problem of viscous fluid to the surface of the plastic film is effectively solved.

The invention provides an alarm method. The method comprises the steps of obtaining a health information search instruction, wherein the health information search instruction carries a preset search distance; obtaining the distance between the at least one target terminal and the mobile terminal and target user health information stored in the at least one target terminal within a preset search distance according to the health information search instruction, and then, giving an alarm to the user according to the distance and the health information of the target user. When the user of the mobile terminal is in an environment which is not easy to be healthy, the mobile terminal can timely give an alarm to the user so as to prevent the health of the user from being threatened.

The invention relates to a 3D printer provided with an air filtering device. The 3D printer comprises a box body and a sealing door hinged to one side of the box body; a printing assembly is arrangedin the box body; an air inlet fixed to the box body is formed in the upper side of the printing assembly; a dust receiving box fixed to the box body is arranged below the air inlet and located above the printing assembly; a mounting groove fixed to the box body is formed in one side of the dust receiving box; an air filtering box is inserted into the mounting groove; the air filtering box communicates with a negative-pressure induced draft fan fixed to the side wall of the box body; and an air guide pipe communicating with the air filtering box is fixedly arranged on one side of the mounting groove. In the using process of the 3D printer, air enters the box body from the air inlet, makes contact with a printing material in the box body and then is pumped out of the filtering box through the air guide pipe by the aid of the induced draft fan, harmful substances are filtered out and retained in the filtering box after the air is filtered by the air guide pipe and the filtering box, and the purified air is discharged out of the box body by the aid of the induced draft fan.

The invention discloses a paint spraying device for a car steel plate. The paint spraying device for the car steel plate comprises a paint spraying disc, a plate fixing frame, a visible sealing door, absorbing discs, a side plate, a base, a paint feeding pipe, a burning furnace, an electric ring, a rotating disc, a spraying frame, a first telescopic column, a universal ball, a spraying head, a spraying hole, an electromagnetic adsorbing plate, a second telescopic column, an electricity connecting pipe, a third telescopic column and an absorbing and sending plate. The paint spraying device for the car steel plate has the beneficial effects that the paint spraying device adopts rotating type paint spraying design, paint spraying operation is conducted, meanwhile, the second telescopic column on the plate fixing frame also drives the steel plate to rotate, the second telescopic column is matched with the universal ball on the spraying frame to make the praying head to swing in any direction, paint spraying of the paint spraying device on the car steel plate is more comprehensive and uniform, the high quality and high efficiency of paint spraying are ensured, the multiple absorbing discs absorbs residual paint spraying particles, the residual paint spraying particles are absorbed and sent into the burning furnace for conducting burning purification through the paint feeding pipe, threat of the paint spraying particles on fitness of human bodies is prevented, the safety and environmental protection property of using the paint spraying device are ensured, the paint spraying device is convenient to operate, and components are flexibly connected.

The invention relates to a magnesium oxide-silicon carbide composite for the upper part of a copper smelting converter and a preparation method of the composite. The technical scheme is as follows: firstly, 40wt%-60wt% of fused magnesia particles, 5wt%-25wt% of silicon carbide particles, 6wt%-16wt% of sintered magnesia fine powder, 5wt%-15wt% of zircon fine powder, 4wt%-8wt% of raw alumina micro powder, 3wt%-7wt% of titanium oxide fine powder, 1wt%-3wt% of monatomic silicon fine powder and 2wt%-5wt% of nickel oxide fine powder are taken as raw materials, 6wt%-10wt% of zirconium oxide sol and 1wt%-3wt% of cerium oxide micro powder are added, uniform mixing, forming and drying are performed, the obtained mixture is kept at the constant temperature of 1,250-1,450 DEG C in a carbon embedded atmosphere for 2-8 h, then impregnated in a zirconium oxychloride solution for 0.5-3 h and kept at the constant temperature of 600-900 DEG C for 2-6 h, and the magnesium oxide-silicon carbide compositefor the upper part of the copper smelting converter is obtained. The produced product has the characteristics of environmental friendliness, low apparent porosity, high anti-stripping capacity and excellent residue permeation corrosion resistance.

The invention discloses a high-safety electric saw special for felling. The electric saw comprises a strip-shaped plate, two symmetrically-arranged supporting frames are arranged at the left end of the lower surface of the strip-shaped plate, first clamping pieces of the supporting frames are fixedly connected to the lower surface of the strip-shaped plate, a bottom plate is arranged at the fixedends of first electric telescopic rods of the supporting frames, four evenly-distributed trundles are arranged on the side face of the bottom plate, and an adjusting frame is arranged at the right endof the upper surface of the bottom plate. The high-safety electric saw special for felling is convenient to move, convenient to fix and good in stability, can be limited and fixed; the inclination angle and the height of the electric saw can be adjusted; and the position of the electric saw can be indirectly adjusted through the driving device, so that the electric saw can complete felling work,damage to the health of a feller due to close-range operation of wood chips can be avoided, meanwhile, threats to the health of the feller when trees topple over can be avoided, safety is high, and use is convenient.