38results about How to "Slow down the spread" patented technology

The invention discloses a laser additive manufacturing method for an aluminum / titanium alloy gradient structure, and belongs to the technical field of laser additive manufacturing. The laser additive manufacturing method comprises the steps that TiNbVZr or TiNbV high-entropy alloy powder is used for preparing the high-entropy alloy transition layer on the surface of titanium alloy through the laser additive manufacturing process, and then the aluminum alloy layer is prepared on the surface of the high-entropy alloy transition layer through the laser additive manufacturing process. According to the preparation method, the aluminum / titanium alloy gradient structure with high performance is prepared by combining optimization of the intermediate transition layer of the high-entropy alloy with two preferable components with a laser additive manufacturing technology, and the problems of interface cracking and low bonding strength of the current aluminum / titanium alloy can be effectively solved.

The invention discloses a novel Topcon solar cell double-sided rate improvement method, which belongs to the field of Topcon cells, and comprises the following steps: selecting an N-type silicon substrate and carrying out double-sided texturing to obtain a textured silicon wafer; performing boron diffusion on the front surface of the textured silicon wafer to form a P + doping layer and a borosilicate glass layer; removing the borosilicate glass layer on the front surface of the silicon wafer after boron diffusion and the doped layer expanded on the back surface and the edge of the silicon wafer; a first tunneling oxide layer is formed on the surface of the silicon wafer substrate, and three doped polycrystalline silicon layers with different densities are deposited and formed without deposition pressure; performing low-pressure oxidation to form a silicon dioxide masking film, and then performing phosphorus diffusion segmented propulsion to obtain an initial battery piece; removing the wound-plated polycrystalline silicon on the front surface and the edge of the primary battery piece; printing silver aluminum paste, printing silver paste on the back surface, drying and sintering, and then carrying out light injection treatment. The double-sided rate of the Topcon battery is improved through the cooperation of the steps of controlling the alkali polishing process time, reducing the size of a back tower footing after alkali polishing, reducing the number of silk-screen printing grid lines, reducing the width of the grid lines and the like.

The utility model belongs to the technical field of vibrating screens, and particularly relates to a vibrating screen for plastic additive master batch processing, which comprises a screen frame with an upper opening and a lower opening, a screen mesh arranged at the bottom of the screen frame, a speed reduction component arranged in the screen frame and matched with the screen mesh, a screen drum arranged at the bottom of the screen frame, and a conical plate arranged on the inner side of the bottom of the screen drum. A vibrating frame is arranged at the bottom of the screen drum, a vibrating motor is arranged on the vibrating frame, a plurality of springs are arranged at the bottom of the vibrating frame, a support is arranged at the bottom end of each spring, and a base is arranged at the bottom end of each support. A first output channel connected with the interior is arranged on one side of the screen frame, and a second output channel connected with the interior is arranged on one side of the screen drum. Compared with the prior art, the vibrating screen has the advantages that the speed reducing assembly is arranged, under the condition that high-frequency output of the vibrating motor is guaranteed, the speed of materials diffusing from the center to the periphery is greatly reduced, the screening time of the materials is prolonged, and therefore the screening precision is improved.

The invention relates to the technical field of coating part preparation, in particular to a zinc-iron coating part and a preparation method thereof. The preparation method comprises the steps that a part steel base body is annealed, and an annealed base plate is obtained; carrying out hot dipping on the annealed substrate by using a zinc-containing plating solution, and then carrying out alloying treatment to obtain a rough steel plate containing a zinc-iron plating layer; the rough steel plate is subjected to cold stamping forming, and a preformed part is obtained; according to the thickness of the preformed part, the optimal hot stamping processing parameters are determined; and the rough part is subjected to heat treatment through the hot stamping treatment parameters, and the zinc-iron coating part is obtained. The hot stamping treatment parameters comprise austenitizing heating temperature and austenitizing heat preservation time; and the thickness of the preformed part is in positive correlation with the temperature and the time respectively. According to the preparation method, the correlation between the thickness of the preformed part and the austenitizing heating temperature and the austenitizing heat preservation time is defined, so that the content of a brittle gamma phase in a zinc-iron coating is reduced; and further, the liquid metal embrittlement sensitivity of the preformed part in the hot stamping treatment process is reduced.

The invention discloses a preparation method of a microalloyed high-temperature-resistant aluminum alloy. The high-temperature-resistant aluminum alloy is prepared from the following components in percentage by mass: 4.7 percent to 5.04 percent of Cu, 0.98 percent to 1.08 percent of Fe, 1.45 percent to 1.6 percent of Ni, 0.51 percent to 0.56 percent of Mn, 0.45 percent to 0.55 percent of Mg, 0.18 percent to 0.2 percent of Ti, 0.2 percent to 0.32 percent of Ce, 0.05 percent to 0.3 percent of Zr, impurities and the balance of Al. By adding Mn, an Al20Cu3Mn2 precipitated phase with high thermal stability can be formed, and Mn is gathered around a theta'phase to inhibit coarsening of the theta 'phase, so that the high-temperature strength and the alloy performance of the aluminum alloy are improved. Fe and Ni are added, so that a stable iron-rich phase Al9FeNi is formed, and the thermal stability and the high-temperature strength of the alloy are also favorably improved. Ti is attached to the periphery of a theta'precipitated phase and hinders coarsening of the theta 'precipitated phase, grains are refined, and the high-temperature strength of the aluminum alloy is cooperatively improved. Ce can form an Al-Ce-M (M = Fe, Ti) intermetallic compound, and can also synergistically improve the thermal stability of the aluminum alloy. In addition, by adding the compounded refining agent, the degassing and impurity removal efficiency can be improved, and after deep purification, the high-temperature-resistant strength of the aluminum alloy is promoted. And the effect of improving the high-temperature strength of the alloy is integrally achieved.

The invention provides a photoresist composition and a preparation process thereof. The photoresist composition is prepared from the following raw materials in parts by weight: 80.0 to 100.0 parts of solvent, 20.0 to 40.0 parts of resin, 3.0 to 5.0 parts of photoinitiator, 1.0 to 3.0 parts of light stabilizer, 1.5 to 2.5 parts of tackifier, 1.0 to 1.5 parts of monomer, 1.0 to 2.0 parts of acid diffusion inhibitor and 0.5 to 2.0 parts of flatting agent. Wherein the acid diffusion inhibitor is prepared from perfluorocyclohexane, benzo-15-crown ether-5 and L-ethyl lactate, and the mass volume ratio g / mL of the perfluorocyclohexane to the benzo-15-crown ether-5 to the L-ethyl lactate is (2-3): (1-2): (1-2). According to the acid diffusion inhibitor disclosed by the invention, through the combined action of different mechanisms of the perfluorocyclohexane, the benzo-15-crown ether-5 and the L-ethyl lactate, the diffusion speed of acid is slowed down, so that the boundary between an exposure region and a non-exposure region is clearer, and the resolution ratio of photoresist is improved. By modifying the methacrylic resin, the surface energy and polarity of the methacrylic resin are changed, and the solubility of the resin after exposure is remarkably changed, so that the photoresist is easier to remove in a developing solution, and the definition and resolution of a pattern are improved.

The application discloses a hot water boiler based on a porous medium burner, which comprises a hot water boiler shell, wherein the hot water boiler shell comprises a boiler barrel, the outer side of the boiler barrel is provided with a water jacket for storing water, and the inside of the boiler barrel is fixedly provided with a porous medium burner; the inner cavity of the porous medium burner comprises a combustion reaction zone, the two ends of the combustion reaction zone are provided with anti-backfire areas, the two ends of the porous medium burner are provided with mixed gas inlets, the mixed gas inlets are connected with mixed gas input pipelines, one end of the mixed gas input pipelines extends out of the hot water boiler shell and is connected with a gas fuel supply device; the porous medium burner is internally provided with an ignition device, mixed gas flows into the combustion reaction zone from the mixed gas input pipelines and is ignited by the ignition device, heat generated by combustion of the mixed gas heats water in the water jacket, flue gas is discharged from the combustion reaction zone through the pores of the porous medium of the porous medium burner and is discharged into a flue gas treatment mechanism connected with the hot water boiler shell, the gas utilization rate is improved, and the heat diffusion speed is slowed down.

The utility model relates to the technical field of cable manufacturing, and discloses a double-layer co-extrusion sheath cable which comprises a conductor, a conductor shielding layer, a crosslinked polyethylene insulating layer, an insulation shielding layer, a semi-conductive water-blocking tape, a soft round copper wire, a soft pure copper tape, a non-conductive water-blocking tape and a CPP tape from inside to outside. According to the double-layer co-extrusion sheath cable, the inner sheath layer and the outer sheath layer are arranged, the inner sheath layer is made of the flame-retardant PVC material with the oxygen index larger than or equal to 32%, a carbonization layer can be rapidly formed under the condition of high temperature or open fire, oxygen is effectively isolated, flame-retardant gas is released, and flame is prevented from spreading towards the interior of the cable, and the outer sheath layer is made of the high-hardness MDPE material. Although the flame retardance is general, the flame diffusion speed can be slowed down, and through the synergistic effect with the inner layer PVC, the overall flame retardant grade of the cable reaches the V-0 grade (UL 94 standard), the high-flame-retardant scene requirement is met, and the flame retardant property is further remarkably improved.

The invention discloses a pharmaceutical composition for treating or preventing ovarian cancer, the pharmaceutical composition comprises a PARP inhibitor, a VEGF inhibitor, an excipient, a disintegrating agent, a lubricant and a latent solvent, various raw materials are combined and mixed through a proper process to obtain the pharmaceutical composition for treating ovarian cancer, the PARP inhibitor and the VEGF inhibitor are matched for pharmaceutical production, the formula is novel, and the pharmaceutical composition is suitable for clinical application. The preparation method is simple, the process is ingenious, the growth of the ovarian tumor is synergistically inhibited through multiple mechanisms by utilizing the matched multi-target effect of various inhibitors, the treatment and inhibition effect on the ovarian tumor is improved, the selection and proportioning of auxiliary materials are adopted, the adverse reaction of the medicine is reduced, the workability of medicine granulation is improved, the production is convenient, and the quality of a finished product is ensured; meanwhile, by adopting an oral tablet mode, the traditional Chinese medicine composition has good oral property, the compliance of a patient is improved, and the traditional Chinese medicine composition has a good application prospect.

The invention relates to the technical field of knitted fabrics, in particular to a three-dimensional knitted fabric and a preparation process thereof. The preparation method comprises the following steps: taking 4, 4 '-diphenyl ether dicarboxylic acid, a dicarboxyl flame retardant, ethylene glycol and butanediol as raw materials, carrying out melt polycondensation reaction to prepare a modified polyester material, and carrying out melt spinning, winding and stretching treatment on the modified polyester material to obtain the modified polyester fiber. Blending the modified polyester fibers and the modified viscose fibers to obtain blended yarns; the blended yarn and the spandex filaments are subjected to a double-face weft knitting process, and gray fabric is obtained; the three-dimensional knitted fabric is obtained by sequentially performing scutching, washing and deoiling, blank fixing, dyeing, reducing and washing, dewatering and drying and shaping on gray fabric. The prepared three-dimensional knitted fabric not only has excellent flame retardant property, can effectively resist flame spreading and ensure safety, but also has excellent hydrophilicity, and the wearing comfort is remarkably improved.

The invention relates to the technical field of vinyl acetate-acrylic emulsion preparation methods, in particular to a self-thickening vinyl acetate-acrylic emulsion and a preparation method thereof.According to the self-thickening vinyl acetate-acrylic emulsion prepared through the method, an anionic emulsifier and a nonionic emulsifier are used in cooperation, the stability of the emulsion is improved, and the stability of the emulsion is improved; the used nonionic emulsifier can further increase the thickness of a hydrated layer, so that the defect of poor stability of the vinyl acetate-acrylic emulsion is overcome; secondly, the acrylic hydrophilic monomer is added, so that the prepared vinyl acetate-acrylic emulsion has a self-thickening effect, and the production cost is reduced on the basis of improving the stability and powder holding capacity of the emulsion; and finally, the added crosslinking monomer can be subjected to crosslinking reaction with vinyl acetate and alkyl acrylate monomers to form a crosslinking film, so that the crosslinking density of the vinyl acetate-acrylic emulsion and the bond energy of molecular chain group connection are greatly improved, and the adhesive force, the tensile strength and the elongation at break are improved.

The present application relates to a safety structure for an integrated pipe gallery or tunnel based on a drainage system, and relates to the technical field of pipe gallery construction safety, which includes a drainage channel, which is opened on both sides of the bottom wall of the pipe gallery or tunnel along the length direction of the pipe gallery or tunnel, and a water storage chamber is spaced along the length direction of the drainage channel; a water curtain forming device is installed between the two drainage channels, and the water curtain forming device includes an arc-shaped water spraying mechanism and a clamping guide mechanism, the arc-shaped water spraying mechanism is installed on the clamping guide mechanism, the clamping guide mechanism is detachably installed at a position near the water storage chamber in the drainage channel, the clamping guide mechanism is used to fix the arc-shaped water spraying mechanism at a position near the water storage chamber, and the arc-shaped water spraying mechanism is used to absorb the water in the water storage chamber and form a truncated water curtain in the pipe gallery or tunnel. The present application can improve the safety problem when constructing in locations where groundwater and methane areas exist.

The invention discloses a fluid loss agent for multipolymer oil well cement and a preparation method thereof, and belongs to the technical field of fluid loss agent preparation. The fluid loss agent for the multipolymer oil well cement is prepared from the following components in parts by weight: 42 to 56 parts of high-molecular polymer, 4 to 6 parts of bentonite, 1 to 3 parts of disodium ethylene diamine tetraacetate, 10 to 13 parts of composite hydrating agent, 8 to 12 parts of distilled water and 0.2 to 0.4 part of ammonium persulfate, the high-molecular polymer is prepared from dimethylamino propyl acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, glycidyl methacrylate, 3-propyl-2-olefin acyloxy propane-1-sodium sulfonate and 2-aminoethanethiol, and the molecular polymer is prepared from the following components: 2-dimethylamino propyl acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, glycidyl methacrylate, 3-propyl-2-olefin acyloxy propane-1-sodium sulfonate and 2- the composite hydrating agent is prepared from acrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, sodium lignin sulfonate, corn fiber and butyl succinic anhydride. The fluid loss agent prepared by the method has excellent fluid loss performance, temperature resistance and salt resistance.

The present application belongs to the technical field of fruit tree disease prevention and control, and particularly relates to a method for removing sporadic citrus Huanglongbing trees in citrus orchards. According to the epidemiological characteristics of citrus Huanglongbing, the control strategy of 'completely removing diseased plants, strictly preventing and controlling citrus psyllids, and comprehensively preventing and controlling' is implemented at sporadic disease points in the diffusion front area. The sporadic disease point orchards are promptly cleaned of diseased trees, and the diffusion front area is comprehensively prevented and controlled to prevent the disease from occurring again. In this way, disease information and risk warnings can be promptly released, the removal of diseased trees and the strict prevention and control of citrus psyllids can be achieved, the invasion and reproduction of exogenous psyllids can be hindered, the risk of healthy seedlings getting sick can be reduced, and the spread of citrus Huanglongbing can be blocked. The present application provides technical support for delaying the further spread of citrus Huanglongbing and saves human and material resources.

The invention relates to an ultra-high molecular weight polyethylene fiber with a surface hairiness structure as well as a manufacturing method and application of the ultra-high molecular weight polyethylene fiber. The ultra-high molecular weight polyethylene fiber of the present invention has a core and hairiness covering at least a portion of the surface of the core, wherein the hairiness has an average length of 1-100 [mu] m and an average density of 1-50 pieces / 100 [mu] m. The surface of the obtained fiber has a surface hairiness structure, so that the surface roughness and the specific surface area are increased, and the fiber is more easily compounded with an adhesive.

The invention discloses a sintered neodymium-iron-boron magnet and a preparation method and application thereof, and the sintered neodymium-iron-boron magnet comprises the following components in percentage by mass: 28-32% of Re which is selected from at least one of Pr, Nd, Dy, Tb and Ho; b: 1.000% to 1.080%; m at least comprises Zr and / or Ti, and the sum of Zr and Ti is larger than 0.1% and smaller than or equal to 0.2%. According to the magnet, the content of the B element is increased, existence of a proper amount of boron-rich phase is guaranteed, in the diffusion process of the sheet magnet, the diffusion effect of the heavy rare earth dysprosium element or terbium element towards the interior of the magnet can be delayed, and Hcj and Hk / Hcj reduction caused by excessive diffusion are prevented.

The utility model relates to the field of bus ducts, and discloses a bus duct with a fire extinguishing function, which comprises a bus duct body, an alarm is fixedly arranged on one side of the upper end of the bus duct body, and a temperature sensor is fixedly arranged on one side of the upper end in the bus duct body. A smoke sensor is fixedly arranged on the other side of the upper end of the interior of the bus duct body, flame-retardant plates are fixedly arranged on the two sides of the interior of the bus duct body, and a fire extinguishing air bag is fixedly arranged in the bus duct body. According to the utility model, the bus duct is provided with the puncturing assembly and the fire extinguishing air bag, and carbon dioxide gas used for extinguishing fire is stored in the fire extinguishing air bag, so that when the bus duct is on fire, the puncturing assembly stretches out and draws back through the operation of the miniature electric telescopic rod, thereby driving the connecting block to stretch out and draw back and driving the puncturing needle to move; and therefore, carbon dioxide flows out from the interior of the fire extinguishing airbag to realize fire extinguishing.

The utility model relates to the technical field of color box processing equipment, and provides a color box processing spraying device with a protection mechanism, which comprises an operation table and a fixing plate, the fixing plate is fixed on one side of the top end of the operation table, a supporting plate is fixed on the top end of the fixing plate, and a moving structure is arranged on the top of the supporting plate. The protective structure is arranged, the first protective plate and the second protective plate are in sliding connection with the operation table, the first protective plate and the second protective plate can be conveniently taken out from the interior of the operation table to be cleaned, and during spraying, the first protective plate, the second protective plate, the fixing rod, the door plate and the top cover enclose the spray head, so that the diffusion speed of pigment can be reduced, workers are prevented from inhaling the pigment, and the working efficiency is improved. The spraying device with the protection mechanism for color box processing has the advantages that air pollution is reduced, meanwhile, pigment can be prevented from being splashed to the body of a worker, a certain protection effect is achieved, the protection function of the device is achieved, and the safety of the spraying device with the protection mechanism for color box processing in use is improved.

The invention relates to a method for constructing a hollow porous material through jujube peel fibers and carrageenan, an obtained product and application, and belongs to the technical field of food processing. The jujube peel fiber is combined with carrageenan, the fiber can serve as a framework support to form a stable hollow porous structure, the hollow porous structure provides larger surface area and pore volume, and the loading capacity of hydrophobic active ingredients can be increased. The inner surface of the prepared hollow porous structure material can adsorb hydrophobic active ingredients through non-covalent interaction such as physical adsorption and Van der Waals force. The structure can effectively protect the hydrophobic active component from being influenced by the external environment, so that the stability and bioavailability of the hydrophobic active component are improved. The structure not only can effectively load and protect hydrophobic components, but also can adjust the pore size by adjusting the ratio of the fibers to the carrageenan, and the smaller pore size can slow down the diffusion speed of the hydrophobic active components and prolong the release time, so that the hydrophobic active components can be released as required. The bioavailability of hydrophobic nutritional ingredients is improved.

The invention discloses a magnetic-core-free arched MEMS inductor and a preparation method, and belongs to the technical field of semiconductors. The arched MEMS inductor without the magnetic core comprises a glass substrate, an inductor coil, a fuse bonding pad and a non-photosensitive polyimide coating, the inductor coil comprises an inductor bottom coil and an inductor top arched coil, the fuze bonding pad comprises a first fuze bonding pad and a first connecting line thereof, and a second fuze bonding pad and a second connecting line thereof, and the inductor bottom coil, the first fuze bonding pad and the first fuze bonding pad are electroplated on the glass substrate. The two ends of the inductor coil are connected with the first fuze bonding pad and the second fuze bonding pad respectively, the non-photosensitive polyimide coating is attached to the surface of the glass substrate and serves as a supporting layer of the inductor top arch coil, and the inductor top arch coil and the non-photosensitive polyimide coating follow the shape. The top surface of the fuze pad and the top surface of the inductor top arch coil are not covered by the non-photosensitive polyimide coating. By using the method, the preparation time is shortened by 15-20%.

This utility model relates to the field of gas filling protection technology and discloses an automatic gas filling protection device, including an equipment frame, an equipment frame fixedly installed on the upper part of the equipment frame, a hydraulic rod fixedly installed on the upper surface of the equipment frame, a lifting plate fixedly installed at the lower end of the hydraulic rod, a gas pipe installed at the lower part of the lifting plate, an installation plate installed on the rear side of the equipment frame, a lead screw rotatably installed on the inner wall of the installation plate, a moving block threaded on the outer side of the lead screw, a motor fixedly installed on the upper part of the installation plate, a connecting block fixedly installed on the outer side of the moving block, a protective cover fixedly installed on the outer side of the connecting block, and a bottom clamping plate fixedly installed in the inner middle layer of the equipment frame. This device can prevent accidents involving gas cylinders. In the event of a gas cylinder explosion, it can effectively block or buffer the impact force of fragments, limiting the scope of the hazard. Simultaneously, the protective cover can slow down the diffusion rate of leaked gas, buying time for operators to evacuate or handle emergencies.

The invention belongs to the field of cultivation of betula alnoides timber forests, and particularly relates to a comprehensive prevention and control method for betula alnoides young forest stage canker, which comprises the following steps: (1) regulating and blocking a small environment of a planting area, and constructing a forest stand small environment for reducing the occurrence of diseases through intermediate cutting to improve the disease prevention capability of the forest stand; the distance of the blocky intermediate cutting area is reasonably controlled, and the disease transmission path and the diffusion speed are blocked or reduced; and (2) climate change monitoring and disease early warning: analyzing the relationship between disease occurrence and rainfall and temperature environmental factors to find out a disease occurrence rule and propose an early warning strategy. According to the method, the disease prevention capability of the forest stand is improved, the disease occurrence rule is found out, the appropriate chemical prevention time is selected, and the growth vigor of affected forest trees is promoted to be quickly recovered and the disease influence is reduced through combination and configuration of different agents, mastering of a chemical prevention method and reasonable additional application of leaf fertilizer; the method is an important technology for actively coping with climate change influence in the field of artificial forest cultivation.

A polyurethane adhesive for road paving comprises the following components in parts by weight: prepolymer A, 15-30; prepolymer B, 10-30; prepolymer C, 5-20; diluent, 14-26; stabilizer, 0.01-0.1; wherein prepolymer A is a prepolymer of polyether polyol and toluene diisocyanate; prepolymer B is a prepolymer of vegetable oil polyol and diphenylmethane diisocyanate; prepolymer C is a prepolymer of long-chain fatty monool and polymethylene polyphenyl isocyanate. The preparation method is simple. When the polyurethane adhesive is mixed with aggregate to prepare polyurethane concrete, the obtained polyurethane concrete has a long construction open time, high splitting strength, high dynamic stability, and high low-temperature bending strain.

The application discloses a preparation method of magnesium sulfide / MXene composite material, and products and applications thereof. Lithium halide is added into strong acid to dissolve Ti3AlC2 powder, and the treated Ti3AlC2 powder is collected when the pH value is 6 after washing, centrifugation, vacuum drying, ultrasonic bath and centrifugation. The green supernatant is collected to obtain a layered MXene colloidal suspension. The MXene dispersion liquid and oleylamine are stirred to form an emulsion. The mixed dispersion is heated to form Mg-O-X / MXene. A solution containing thioacetamide in oleylamine is injected into the three-necked bottle. After heating, stirring, cooling, washing, centrifugation and freeze drying, the magnesium sulfide / MXene composite material is obtained. The first discharge specific capacity of the magnesium sulfide / MXene composite material is 199.7 mAh / g at a current density of 500 mA / g, and the discharge specific capacity is 187 mAh / g after 50 cycles, and the capacity retention rate is 93.6%.

The utility model discloses an inorganic cloth fireproof roller shutter, which is characterized in that a drain pipe is arranged below a roller shutter structure, and a plurality of spray heads are uniformly arranged on the lower side of the drain pipe along the direction of a notch, so that a water spray system can be started at the first time when a fire disaster or toxic smog occurs; water mist sprayed by the spray heads quickly forms a continuous water curtain barrier in front of the roller shutter. The water curtain not only has a physical isolation effect, but also can effectively capture and cool high-temperature smoke and harmful particles, obviously reduce the concentration and diffusion speed of smoke, and prevent the smoke from spreading from a fire disaster area to other safe areas. Compared with a traditional dry type fireproof roller shutter, the structure improves the smoke prevention performance, and the flowing path of smoke in a building in the initial stage of a fire disaster can be controlled easily.

The invention discloses a concave permanent magnet structure, which belongs to the technical field of vacuum electronics, solves the technical problems of surface damage and plasma generation of a permanent magnet anode in a zero field region, is in a circular ring shape, and comprises an axial leftward magnetized magnetic block, an axial rightward magnetized magnetic block and a radial circle center magnetized magnetic block. The radial magnetizing magnetic block towards the circle center is a circular ring with a step which is located on the right side of the inner ring. And the axially leftward magnetized magnetic block and the axially rightward magnetized magnetic block are positioned in the step. An interval groove is formed between the axially leftward magnetized magnetic block and the axially rightward magnetized magnetic block, and the ratio of the axial width to the radial depth of the inner ring of the interval groove is 35%-55%. The magnetization direction of the axial leftward magnetization magnetic block is leftward in the axial direction, the magnetization direction of the axial rightward magnetization magnetic block is rightward in the axial direction, and the magnetization direction of the radial circle center magnetization magnetic block is towards the circle center in the radial direction. The device is used for inhibiting plasma generation in a null field region in a permanent magnet structure and charged particle backflow caused by the plasma generation.

The utility model relates to the technical field of induction smelting furnaces, in particular to a vacuum induction directional zone smelting furnace which comprises a smelting furnace body, and a dustproof assembly is installed on the top of the smelting furnace body. The dustproof assembly comprises a longitudinal frame fixedly connected with the smelting furnace body, air holes penetrating through the longitudinal frame are formed in the two sides of the longitudinal frame correspondingly, a water storage tank is fixedly connected to the bottom of the inner side of the longitudinal frame, a heat dissipation assembly is installed at the top of the water storage tank, and a retarding assembly is installed on the side, close to the smelting furnace body, of the longitudinal frame. The heat dissipation assembly comprises an outer pipe fixedly connected with the water storage tank, a metal hollow column with one end movably extending to the outside of the outer pipe is arranged in the outer pipe, and an elastic rope is fixedly connected between the top of the metal hollow column and the longitudinal frame. The technical problems that according to an existing induction smelting furnace, it is difficult to stop dust from getting close to the smelting furnace without dead corners through the air pressure difference, dust around the smelting furnace is cleaned away at the slow air flowing speed, and the speed of heat diffusing around is decreased when the smelting furnace is opened are solved.

The present invention belongs to the field of semiconductor device preparation, and specifically relates to a method for preparing an air insulation layer based on back-to-back integration and a semiconductor device, wherein the method for preparing the air insulation layer comprises the following steps: Step 1: sequentially performing a silicon photonic front-end process and a silicon photonic back-end process on a first SOI wafer, wherein the back-end process does not include making a thermal adjustment electrode; bonding with a carrier wafer; and removing the silicon substrate of the first SOI wafer; Step 2: etching and hollowing out to form an air insulation layer, bonding an epitaxial wafer to the first wafer, wherein the epitaxial wafer isolates the air insulation layer from the outside to form a closed cavity. The air insulation layer formed by the present invention can reduce the complexity of the process design while reducing the additional power consumption brought by the thermal adjustment device, and at the same time, improve the stability of the semiconductor device without affecting the subsequent process and packaging; the size and depth controllability of the formed air insulation layer are increased, thereby improving the process reliability.

The invention belongs to the technical field of oil exploitation, and particularly relates to an oil-based foam oil displacement system based on stability augmentation of high-temperature-resistant nano-particles and a preparation method and application thereof.The stability augmentation oil-based foam oil displacement system is characterized in that 0.5 wt%-1.5 wt% of nano-particles, 0.5 wt%-2 wt% of a nonionic surfactant Span20 and 0.1 wt%-1.0 wt% of a nonionic surfactant JQ-1 are adopted, the half-life period of foam drainage can be 15-22 min under the conditions that the pressure is 1 MPa and the temperature is 100 DEG C, and the stability augmentation oil-based foam oil displacement system is stable. And the half-life period of foam is 9-15 days. The stability-enhancing oil-based foam oil displacement system based on the high-temperature-resistant nano-particles is high in foaming capacity in an oil solvent, the surface tension of the oil solvent can be remarkably reduced, high foaming performance and foam stability are achieved, and the preparation process is simple, green and environmentally friendly.

The invention relates to the technical field of pesticide stirring, in particular to a pesticide mixing and stirring device for an agricultural planting and fertilizing robot. The device comprises a ploughing device and a treatment device arranged in the ploughing device, the ploughing device plows gullies on the land when moving, the treatment device collects soil, after collection, the soil is refined, after treatment is completed, the soil and pesticide are mixed, and then the mixture is mixed with the pesticide. And the soil mixed with the pesticide is filled in gullies ploughed by the ploughing device. A gully is ploughed on the land through the ploughing device, soil is collected through the processing device, the soil and pesticide are mixed together and guided into the gully, then the soil is guided through the processing device, the soil mixed with the pesticide covers the gully through the soil, and therefore the situation that the pesticide is sprayed on plants is avoided, and the effect of preventing the pesticide from being sprayed on the plants is achieved. Meanwhile, the pesticide is mixed with the soil and covers the soil, so that the diffusion speed of the pesticide in the air is reduced.