63results about How to "Large aperture" patented technology

The utility model relates to a kind of spray panels for liquid-cooled energy storage integrated cabinet, it includes plate body, the continuous fluid passage is set up on the plate body upper surface, the fluid passage is equipped with liquid inlet;Multiple spray holes are set up on the plate body, each The spray hole is all through the plate body and is communicated with the inside of the fluid passage;Along the flow direction of fluid in each branch of the fluid passage, the spray hole aperture that is away from the branch entrance is greater than the spray hole aperture close to the branch entrance;And the cross-sectional area of the fluid passage corresponding to the spray hole that is away from the branch entrance and is communicated is less than the cross-sectional area of the fluid passage corresponding to the spray hole close to the branch entrance and is communicated.The utility model realizes the effect that each hole liquid is consistent, improves energy storage cabinet battery heat dissipation uniformity.

The invention discloses a zoom lens. The zoom lens comprises a focusing lens group with negative focal power, a zoom lens group with positive focal power and a fixed lens group with negative focal power which are sequentially arranged from an object plane to an image plane along an optical axis; the fixed lens group is fixedly arranged, and the focusing lens group and the zoom lens group are movably arranged along an optical axis; the focusing lens group comprises a convex-concave first lens with negative focal power, a biconcave second lens with negative focal power and a convex-concave third lens with positive focal power; the zoom lens group comprises a biconvex fourth lens with positive focal power, a convex-concave fifth lens with positive focal power, a convex-concave sixth lens with negative focal power, a convex-concave / plano-concave seventh lens with positive focal power, a convex-concave eighth lens with negative focal power and a convex-concave ninth lens with positive focal power; the fixed lens group includes a concave-convex tenth lens having a negative refractive power. By the adoption of the technical scheme, the zoom lens has the advantages of being small in size, large in aperture, high in image quality and the like.

A broadband athermal optical system based on a global surface lens is characterized by the following components arranged sequentially from the outside to the inside along the light propagation direction: a protective window, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a detector photosensitive surface (image plane). The protective window, first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, eighth lens, and ninth lens are coaxially arranged with the detector photosensitive surface (image plane). The optical system receives visible light reflections and short-wave infrared radiation information inherent to the target and background, and converges them onto the detector photosensitive surface for photoelectric conversion. It exhibits high sensitivity and relatively low spatial resolution, enabling target detection, identification, and precise positioning under all-weather and complex meteorological conditions. This invention belongs to the field of optical imaging technology. The optical system exhibits excellent imaging quality, strong light-gathering ability, and good environmental adaptability within a wide spectral and temperature range of 0.4μm to 2.3μm and -50℃ to +70℃. It features simple structure, easy assembly and adjustment, high reliability, low cost, good manufacturability, and high yield. It can be widely used in aerospace optical remote sensing, ground-based target tracking and detection, optical imaging guidance, astronomical observation, industrial multispectral imaging analysis and non-destructive testing, and civil security surveillance, with broad application prospects and significant economic benefits.

The application discloses a kind of based on dual atomic norm minimization multipath high-order QAM signal direct positioning method, first, construct distributed multi-sensor array positioning model under multipath environment, receive signal is obtained;Second, the simplified fourth-order cumulant of each sensor array received signal is calculated, and it is extended to obtain virtual signal;Then, respectively construct semi-positive definite constraint problem, and the dual vector is solved to obtain;Finally, all dual vectors are combined to construct cost function and directly search emitter position, and the position estimation value is obtained.The kind of direct positioning method based on dual atomic norm minimization multipath high-order QAM signal that the application designs can effectively locate emitter.In addition, the method makes full use of the characteristics of high-order QAM signal, can extend array aperture, estimates more emitters.The positioning performance of the application is superior to the traditional spatial smoothing subspace data fusion direct positioning method and discrete fourier transform direct positioning method.

The invention provides a metallocene catalyst and a preparation method and application thereof. The method comprises the following steps: providing a first silicate aqueous solution with the pH value of 9-10 as a base solution; mixing the second silicate aqueous solution, inorganic acid and the base solution, and aging at 70-80 DEG C to obtain a first mixed solution; mixing and reacting the first mixed solution, an alkaline substance and organic alcohol to obtain a second mixed solution; mixing and reacting the second mixed solution, an alkaline substance and organic alcohol to obtain a hydrogel system; mixing the hydrogel system with inorganic acid to obtain acidified gel; performing first post-treatment to obtain a silica gel carrier; carrying out thermal activation on the silica gel carrier, and mixing and reacting with an aluminum alkyl solution to obtain MAO modified silica gel; and mixing the MAO modified silica gel with a metallocene compound, reacting, and carrying out second post-treatment to obtain the metallocene catalyst, wherein the alkaline substance comprises one or a combination of more than two of ammonia water, ammonium carbonate and ammonium bicarbonate. The metallocene catalyst has good catalytic activity.

The utility model belongs to the technical field of glass fiber reinforced plastic film gluing equipment, specifically relates to a continuous film scraping device, the utility model discloses a film unwinding device, scraper platform frame is established in the export one side of film unwinding device, glue assembly is established in the arbitrary side of scraper platform frame, at least one oven is established in the export one side of scraper platform frame, traction machine is established in the export one side of oven, film unwinding device is used for releasing film roll and outputting film, and film passes through scraper platform frame, glue assembly and oven in proper order, and moves forward under the traction of traction machine. The utility model is used for solving the technical problem of the poor production environment, the easy failure of spray gun and the high cleaning frequency of spray gun of the film of glass fiber reinforced plastic plate in the prior art.

The utility model discloses a large-aperture half-frame lens, which belongs to the technical field of optical lenses and comprises a first lens group, a second lens group, a third lens group and a fourth lens group which are sequentially arranged from an object side to an image side along an optical axis. The focal lengths of all the lens groups meet the following conditional expressions: 1.2 < f (G1) / f (G2-G4) < 3.7; -3.8 < f (G3) / f (G2-G4) <-1.3; 1.6 < f (G1) / f < 4.8. According to the large-aperture half-frame lens, various aberrations of various wave bands are corrected, the central field of view and the edge field of view have enough resolution, the large-aperture half-frame lens has the advantages of being simple in structure, small in size and large in aperture, and the high resolution of imaging with the object distance from infinity to close distance can be achieved.

This application discloses a microscope objective optical system, relating to the field of optical instrument technology. The system includes a first lens group, a second lens group, and a third lens group. The three lens groups are configured such that the first lens group has positive refractive power, the second lens group has positive refractive power, and the third lens group has negative refractive power. Furthermore, the composition of each of the first, second, and third lens groups is defined, and their focal distances are defined and satisfy preset conditions. Based on this design, the microscope objective optical system has a long working distance, large aperture, high resolution, good imaging performance over a wide wavelength range, and well-corrected chromatic aberration.

This invention discloses a high spatiotemporal resolution millimeter-wave radar imaging system, comprising: a U-shaped antenna array module, wherein the transmitting and receiving antennas are symmetrically distributed in a U-shape, with an element spacing greater than or equal to half a wavelength, adapted to the SAR imaging mechanism, and using an electronic scanning scheme to achieve beam scanning; a radio frequency (RF) module, employing a cyclic one-transmit-multiple-receive mode, completing data acquisition for all transmitting and receiving channels by cyclically switching the transmitting elements to ensure high system refresh rate and spatiotemporal resolution; a signal processing module, receiving multi-channel echo signals, rearranging the echo signals, and using a hardware-parallel accelerated time-domain backpropagation (BP) algorithm for imaging; and a control module, using a microcontroller to control the RF chip of the RF module. This invention verifies the applicability of antenna spacing greater than or equal to half a wavelength in near-field SAR imaging mechanisms, overcomes the dependence of traditional MIMO systems on antenna half-wavelength spacing, achieves high spatiotemporal resolution near-field imaging, and reduces system complexity and cost.

The application discloses a high desalination reverse osmosis membrane and a preparation method thereof, and belongs to the technical field of reverse osmosis membrane preparation. The method comprises the following steps: (1) a first intermediate membrane is obtained by casting a polysulfone film solution on a non-woven fabric layer and then solidifying; (2) the first intermediate membrane is immersed in an aliphatic biological amine solution, a first polyacyl chloride solution is poured onto the surface of the polysulfone porous layer, the membrane sheet is transferred to hot water to hydrolyze the acyl chloride groups into carboxyl groups, and a second intermediate membrane with a first polyamide layer is obtained; (3) the second intermediate membrane is immersed in a polybasic aniline solution, a second polyacyl chloride solution is poured onto the surface of the first polyamide layer, heat treatment is carried out after a certain time of reaction, and finally hot water is used for cleaning, and the high desalination reverse osmosis membrane is obtained. The application constructs a double-layer polyamide reverse osmosis membrane with gradient pore size and interfacial interlocking through a two-step differential interface polymerization process, has ultra-high desalination rate, high water permeation flux, excellent long-term stability and industrialization value, and is suitable for various water treatment scenes.

The application discloses a small-distortion large-view-field high-definition lens based on Q- TYPE aspheric surface, which comprises first lens elements, second lens elements,..., tenth lens elements and an aperture diaphragm arranged in sequence from left to right, the aperture diaphragm is arranged between the fifth lens element and the sixth lens element, two aspheric surfaces are adopted in total, and the front surface of the first lens element and the front surface of the tenth lens element are both Q- type aspheric surfaces. The application applies the novel Q- type aspheric surface to the design of the wide-angle lens, reduces the weight and processing cost of the lens, realizes small distortion, a large aperture and high pixels, strictly limits the structural parameters of the lens elements, finally realizes the size requirements of a long back intercept, a short total length of the system and a small first surface lens, so as to meet the assembly requirements, improves the processing and detection precision to a certain extent due to the excellent characteristics of the Q- type, and improves the optimization efficiency.

This invention provides a method for preparing and applying a catalyst for co-thermal pyrolysis of waste plastics and biomass, comprising the following steps: Step 1, mixing FCC waste catalyst, sodium carbonate, and a metal oxide precursor uniformly to form a powder; Step 2, modifying HZSM-5 molecular sieve with phosphorus; Step 3, mixing the mixture obtained in Step 1, the phosphorus-modified ZSM-5 molecular sieve from Step 2, a binder, and water to form microspheres, calcining to obtain the catalyst for co-thermal pyrolysis of waste plastics and biomass. The catalyst prepared by this invention has a large pore size and pore volume, and when used for co-thermal pyrolysis of waste plastics and biomass, the liquid yield is greater than 70%.

The application discloses a low-cost mid-wave refrigeration athermalization optical system based on a silicon germanium material, which sequentially comprises a fairing, a first lens, a second lens, a third lens, a detector protection glass, a cold light diaphragm and an image plane from outside to inside in the propagation direction of light. The first lens, the second lens, the third lens, the detector protection glass, the cold light diaphragm, the image plane and the fairing are coaxially arranged. The optical system is used for receiving infrared radiation inherent to a target and a background, and converging the infrared radiation onto a photosensitive surface of a refrigeration detector to realize photoelectric conversion, so that the target can be detected, identified and accurately positioned at night or under complex weather conditions. The application belongs to the technical field of optical imaging, can adapt to a harsh missile-borne working environment with a wide temperature range of 110 DEG C and high impact overload, has the characteristics of simple structure, excellent imaging quality, high resolution, strong environmental adaptability, good processing process, easy assembly and adjustment and high yield, is suitable for mass production, and can be widely applied to the fields of optical imaging guidance, search, tracking and reconnaissance.

This invention discloses a core-shell hydrogenation catalyst and its preparation method. The catalyst comprises a core layer and a shell layer, wherein the core layer is alumina loaded with an active metal component, and the shell layer is alumina loaded with molybdenum carbide. The active metal is at least one of Group VIII metals and at least one of Group VIB metals. The preparation method of the catalyst is as follows: first, boehmite powder is mixed with an organic acid solution and dried before introducing the active metal component. Then, after molding, a spherical core layer material is obtained. Then, under rolling spherical conditions, the obtained spherical core layer material, boehmite powder, molybdenum carbide powder, and an organic alcohol polymer solution are mixed evenly to obtain a catalyst precursor. Finally, the catalyst precursor is dried and calcined to obtain the core-shell hydrogenation catalyst. The hydrogenation catalyst provided by this invention is particularly suitable for the hydrogenation conversion of heavy oil, coal tar, and other oils containing macromolecular aromatics and polycyclic aromatic hydrocarbons.

This invention discloses an alumina-based catalytic ceramic membrane loaded with a high content of iron oxide, its preparation method, and its application, belonging to the technical field of inorganic functional ceramic microfiltration membranes and their preparation. This invention solves the problems of low catalyst loading limiting the catalytic activity of existing catalytic ceramic membranes, as well as the complex and costly preparation processes. In preparing the alumina-based ceramic membrane, this invention adds silica to generate a liquid phase during sintering to promote sintering, and adds the catalyst α-Fe₂O₃ to the ceramic powder before sintering. A one-step co-sintering method is used to prepare a ceramic membrane with catalytic function, simplifying the preparation process while increasing the α-Fe₂O₃ content on the surface and inside of the ceramic membrane, utilizing Fe… 3+ It activates the crystal lattice and promotes sintering. Furthermore, with the increase of α-Fe2O3 addition, small pores are expelled during sintering, pore walls shrink, large pores are generated, the pore size of the ceramic membrane gradually increases, and the permeation flux of the ceramic membrane is improved.

This application discloses an optical lens. The optical lens, along the optical axis from the object side to the image side, sequentially includes: a first lens with negative optical power, whose image side is concave; a second lens with optical power, whose object side is concave and image side is convex; a third lens with optical power, whose object side is convex; a fourth lens with positive optical power, whose image side is convex; a fifth lens with positive optical power, whose object side and image side are both convex; a sixth lens with negative optical power, whose object side is concave; a seventh lens with positive optical power, whose object side and image side are both convex; and an eighth lens with optical power, whose object side is convex and image side is concave. The sum of the distances between any two adjacent lenses on the optical axis, ∑AT, and the distance on the optical axis from the object side of the first lens to the image plane of the optical lens, TTL, satisfy: 0.1 ≤ ∑AT / TTL ≤ 0.2.

The application discloses a servo cut-off valve group, which comprises a first valve body and a second valve body integrated on a valve seat. Both the valve bodies are provided with valve cavities, and the valve cavities are internally provided with valve spools driven by a servo motor through a screw rod. The valve bodies are provided with outer ring channels communicated with inlet and outlet of the valve seat on the side surfaces, the outer ring channels are communicated with the valve cavities through a plurality of uniformly distributed lateral flow channels, and the inner walls of the valve cavities are further provided with inner ring channels. The longitudinal flow channels at the bottoms of the two valve cavities are communicated with each other through channels in the valve seat. When the two valve spools synchronously rise above the lateral flow channels, fluid can sequentially pass through the flow channels, and the valve is opened; when the two valve spools synchronously descend to completely cover the lateral flow channels, the valve is closed. The two valve cavities are communicated at the bottoms to form a pressure balance cavity, so that the valve spools are hardly subjected to axial thrust when the valve is closed, and high pressure is converted into sealing force in the radial direction of the valve spools, thereby fundamentally solving the high pressure leakage problem of traditional cut-off valves, and the application is especially suitable for high pressure equipment such as filter presses.

This utility model discloses a heater and a chemical vapor deposition apparatus. The heater includes a heating body comprising multiple circumferentially extending heating segments. These heating segments are sequentially connected by a reversing portion to form at least two radially arranged heating rings. Gaps exist between adjacent heating segments. The reversing portion is provided with a first through-hole communicating with the gaps. The cross-sectional area at the shortest distance between the wall of the first through-hole and the circumferentially extending sidewall of the reversing portion is not less than three-quarters of the cross-sectional area of ​​the heating segment. This utility model extends the service life of the heater by limiting the cross-sectional area at the shortest distance between the wall of the first through-hole and the circumferentially extending sidewall of the reversing portion.

The invention discloses a silicon-aluminum material and a preparation method thereof. After being roasted at 500-700 DEG C, the silicon-aluminum material has the following properties: the content of silicon dioxide is 20-75wt%, and the pore volume is 0.70-1.5 mL / g; and the specific surface area is 280-400 m < 2 > / g. The preparation method of the silicon-aluminum material comprises the following steps: (1) uniformly mixing a silicon-containing compound A, an auxiliary agent A, an aluminum-containing compound and water to obtain a material flow A; (2) carrying out heat treatment on the material flow A in the presence of organic amine to obtain a material flow B; (3) uniformly mixing a silicon-containing compound B, an acidic aluminum-containing compound, an alkaline aluminum-containing compound and water, and treating to obtain a material flow C; (4) mixing the material flow C with an auxiliary agent B to obtain a material flow D; and (5) mixing the material flow B and the material flow D, carrying out hydrothermal treatment, and then washing, drying and roasting to obtain the silicon-aluminum material. The provided silicon-aluminum material shows certain molecular sieve characteristics, has the characteristics of high B acid content and stepped pore channel distribution, and is especially suitable for being used as a carrier of a hydrogenation catalyst.

This invention discloses an optical system and a projection device. The optical system has an object side and an image side arranged opposite each other along the optical axis. From the object side to the image side, the optical system sequentially includes a zoom lens assembly and a focusing lens assembly. The zoom lens assembly includes a first lens assembly with negative optical power, an aperture stop, a second lens assembly with positive optical power, and a third lens assembly with positive optical power, arranged sequentially from the object side to the image side. The aperture stop and the second lens assembly are fixed in position relative to the image side. The first lens assembly and the third lens assembly can move closer to each other or further away from each other along the optical axis to enable the optical system to zoom. The focusing lens assembly has positive optical power and can move to a corresponding position along the optical axis to enable the optical system to focus, thus solving the problem of low zoom efficiency in existing optical lenses.

The invention discloses a low-light-level lens, which comprises a first lens group with positive focal power or negative focal power and a second lens group with positive focal power, and is characterized in that the first lens group comprises a first lens with negative focal power, a second lens with negative focal power and a third lens with positive focal power; the second lens group comprises a fourth lens with positive focal power, a fifth lens with negative focal power, a sixth lens with positive focal power, a seventh lens with positive focal power, an eighth lens with negative focal power and a ninth lens with positive focal power; the combined focal power of the fourth lens, the fifth lens and the sixth lens is phi 456, the combined focal power of the seventh lens, the eighth lens and the ninth lens is phi 789, and the focal power of the low-light-level lens is phi; wherein phi 456 / phi is larger than 0.05 and smaller than or equal to 0.245, and phi 789 / phi is larger than or equal to 0.415 and smaller than or equal to 0.565. According to the technical scheme, the number of the lens groups, the number of the lenses, the focal power matching mode of the lens groups, the focal power matching mode of the lenses and specific values in the low-light-level lens are reasonably set, so that the design of the low-light-level lens with a large aperture can be realized.

The invention discloses a silicon oxide microsphere as well as a preparation method and application thereof. The silicon oxide microspheres are large-aperture silicon oxide microspheres, the specific surface area is 395-750m < 2 > / g, the pore volume is 1.0-3.5 ml / g, and the average aperture is 17-50nm. The silicon oxide microspheres have the characteristics of large specific surface area, large pore volume and large pore diameter, and the catalyst prepared by using the silicon oxide microspheres as the carrier has the advantage that the activity is remarkably improved when the catalyst is applied to olefin polymerization reaction.

The present application relates to a kind of big aperture low distortion fixed focus line sweep lens, first lens, second lens, third lens, fourth lens, fifth lens, diaphragm, sixth lens, seventh lens, eighth lens, ninth lens, tenth lens and eleventh lens are sequentially arranged from object side to image side direction and are made of, second lens and third lens, fourth lens and fifth lens, sixth lens and seventh lens, eighth lens and ninth lens respectively form closely double cemented lens, and each other lens is single lens.The present application overcomes the shortcomings of small aperture, long total length and other defects of existing line sweep lens, adopts eleven lenses cooperation, by optimizing the refractive power, shape, air gap, center thickness, radius of curvature of each lens, with the advantages of large aperture, short total length and low distortion.

The application discloses a kind of porous graphite, preparation method and application of silicon-carbon composite material, belong to battery material technical field.The preparation method is: metal, petroleum coke and its dopant are mixed uniformly, pre-carbonization, graphitization, obtain graphite material, then it is etched to pore by plasma technology, then activation, obtain porous graphite;Finally by silane cleavage method, pass in silane mixed gas and carry out nanometer silicon deposition, passivation, then the obtained material is added to the solution of lithium molybdate and lithium sulfonate and coated, spray drying, obtain double lithium compound coated silicon-carbon composite material.The obtained material utilizes the characteristics that porous graphite itself electronic conductivity is high, and the outer layer coated double lithium salt structure improves ionic conductivity and its first efficiency, and plays the synergistic effect between the two, reduces expansion, improves cycle performance.

The application belongs to the technical field of lithium batteries, and relates to a preparation method of a double-coated silicon-carbon composite material, an electrode and a lithium battery.The method comprises the following steps: placing a lithium dopant and a MOF material in a first organic solvent, adding a template agent and a catalyst, reacting, filtering, freeze-drying and obtaining a gel composite; in an inert atmosphere, the gel composite is heated to a first preset temperature, carbon dioxide is introduced at a preset flow rate, the temperature is lowered, the gel composite is soaked in mixed acid, pickling is performed, vacuum drying is performed, and a porous carbon composite material is obtained; liquid silane, a phosphine derivative, a dispersing agent, the porous carbon composite material and a silane coupling agent are added to a second organic solvent, spray drying is performed, primary carbonization is performed, and a silicon-carbon precursor material is obtained; resin is dissolved in a third organic solvent, a fast ion conductor and the silicon-carbon precursor material are added, secondary carbonization is performed, the temperature is lowered to a second preset temperature, a reducing gas is introduced, and a double-coated silicon-carbon composite material is obtained; the conductivity is improved, the interface stability is improved, and the full charge swelling is reduced.

The utility model provides an end cover assembly of oil -filled air compressor outer rotor motor belongs to mechanical technical field. It solved the problem of inconvenient maintenance of existing outer rotor motor. The end cover assembly of oil -filled air compressor outer rotor motor of present application includes end cover body and the stator support of setting in the end cover body rear side and being the barrel, the inboard wall of stator support is integrally formed with a ring connecting pipe, and the axis of connecting pipe and stator support is parallelly arranged; The rear end surface of end cover body is formed with the connecting portion of ring, and the rear end of connecting portion is inserted into the front end of stator support, and the threaded hole is axially arranged on the rear end of connecting portion, the number of connecting pipe and threaded hole is same and the position is one to one correspondence; The front end surface of connecting pipe is pressed on connecting portion, and the bolt is arranged in each connecting pipe, the head of bolt is pressed on corresponding connecting pipe, and the bolt rod is screwed into corresponding threaded hole. The end cover assembly of oil -filled air compressor outer rotor motor of present application is beneficial to motor maintenance.

The utility model discloses a conductive wire mesh based on a non-metal base material, which belongs to the technical field of conductive materials and comprises a wire mesh structure formed by weaving non-metal wires, the non-metal wires are made of carbon fibers, and a conductive layer is arranged on the surface of the wire mesh structure. According to the conductive wire mesh based on the non-metal base material provided by the utility model, the carbon fiber wire mesh structure is compounded with the conductive layer, so that the conductive wire mesh has the advantages that the surface is smoother and not easy to deform while excellent conductivity and electromagnetic shielding performance are obtained.

This invention discloses a method for preparing silica microspheres, the prepared silica microspheres, and their applications. The method for preparing silica microspheres includes: (1) heating a mixture of n-alkane and pitch under reflux to separate a solid product; (2) mixing the solid product from step (1) with a mixture of aromatics I, a first silicon source, a polyoxyethylene-polyoxypropylene-polyoxyethylene copolymer, and water to obtain a crystallization solution, followed by hydrothermal crystallization and calcination to obtain an intermediate product; (3) mixing the intermediate product from step (2), a second silicon source, a pore-forming agent, and water to obtain a slurry; then, spray-drying and calcining the slurry to obtain the silica microspheres. The silica microspheres prepared by this method have the advantages of large specific surface area, large pore volume, and large average pore size, which significantly improves polymerization activity in olefin polymerization reactions.

The present invention discloses a telephoto lens and an electronic device, which include a first lens, a second lens, a third lens, a fourth lens, and a fifth lens from the object side to the image side; the first lens has a positive optical power, and the object side surface of the first lens is a convex surface; the second lens has a negative optical power, and the curvature radius L2R1 of the object side surface of the second lens satisfies 5 mm < L2R1 < 15 mm; the third lens has a positive optical power, and the curvature radius L3R1 of the object side surface of the third lens satisfies 3 mm < L3R1 < 11 mm; the fourth lens has a positive optical power; the fifth lens has a negative optical power, the object side surface of the fifth lens is a convex surface at the paraxial region, the image side surface of the fifth lens is a concave surface at the paraxial region, and at least one of the object side surface and the image side surface of the fifth lens has at least one inflection point. The telephoto lens and the electronic device of the present invention have the advantages of lens miniaturization, large aperture, and good resolution.

This invention relates to the field of rare earth electrolysis processes, specifically to an oxide feeding control system and its control method, comprising: an oxide feeding device and a control module. The oxide feeding device includes a first hopper and a second hopper located below the first hopper. A control valve is installed between the first and second hoppers. A feeding mechanism is installed below the second hopper, and a loss-in-weight detection scale is installed at the bottom of the second hopper. The control valve includes a valve body, a drive motor, and a transmission component. A valve core is connected to the end of the transmission component. A spring is installed on the side wall of the valve body located below the valve core. A first vibration sensor is provided at one end of the spring near the side wall. The control module is electrically connected to the drive motor, the loss-in-weight detection scale, the first vibration sensor, and the second vibration sensor. When the second hopper is filled to more than 70% of the target weight, the speed of the motor auger is reduced. This invention reduces the impact on the sensors to an acceptable range, thereby achieving precise control.