217results about How to "Same temperature" patented technology

An article made of constituent elements is prepared by furnishing at least one nonmetallic precursor compound, wherein all of the nonmetallic precursor compounds collectively contain the constituent elements. The constituent elements include a titanium-base metallic composition, boron present at a level greater than its room-temperature solid solubility limit, and, optionally, a stable-oxide-forming additive element present at a level greater than its room-temperature solid solubility limit. The precursor compounds are chemically reduced to produce a material comprising a titanium-base metallic composition having titanium boride particles therein, without melting the titanium-base metallic composition. The titanium-base metallic composition having the titanium boride particles therein is consolidated without melting.

An article made of constituent elements is prepared by furnishing at least one nonmetallic precursor compound, wherein all of the nonmetallic precursor compounds collectively contain the constituent elements. The constituent elements include a titanium-base metallic composition, boron present at a level greater than its room-temperature solid solubility limit, and, optionally, a stable-oxide-forming additive element present at a level greater than its room-temperature solid solubility limit. The precursor compounds are chemically reduced to produce a material comprising a titanium-base metallic composition having titanium boride particles therein, without melting the titanium-base metallic composition. The titanium-base metallic composition having the titanium boride particles therein is consolidated without melting.

Provided are methods of screening and identification of bioactivities and bioactive molecules of interest using a capillary array system. More specifically, disclosed are methods of using optical detection and capillary array-based techniques for screening libraries and recovering bioactive molecules having a desired activity or a nucleic acid sequence encoding such bioactive molecules.

The invention provides a blowing device system for air-conditioner, which is able to equalize the cooling air amount blown to the indoor space. In the invention, the blowing device system for air-conditioner includes an air-conditioner (21), an air-supply chamber (23), a plurality of blowing-out devices (30), an air flow measurement part and a blowing-out control part; the air-conditioner (21) inhales the air from an inhalation hole (21a) and blows out the cooling air from a blowing-out hole; the air-supply chamber (23) is formed under the ground and ventilates the air-conditioner (21), in the meantime, the cooling air is blown out to the indoor space (15) through a plurality of blowing-out holes (11a) formed on the floor; the plurality of blowing-out devices (30) inhale the cooling air in the air-supply chamber (23) and blows out to the indoor space (15); the air flow measurement part measures static pressure or wind speed of the cooling air within the air-supply chamber (23); the blowing-out control part, in accordance with the output of the air flow measurement part, enables the blowing-out devices near a stated position within the air-supply chamber to operate when the static pressure or wind speed of the cooling air at the stated position within the air-supply chamber is less than or equal to the limit value, so that the cooling air within the air-supply chamber is blown to the indoor space.

The invention discloses an air conditioner, which comprises an outer casing (2), a fan (1), an adsorption module (6), a heat exchanger set and a water tank (7) arranged in the outer casing (2), wherein the outer casing (2) is provided with an air inlet (3) and an air outlet (8), the air draft side of the fan faces the air inlet, and the air blowing side of the fan faces the air outlet. The adsorption module (6) and the heat exchanger set are sequentially arranged in the outer casing (2) along the air draft path from the air inlet (3) to the air draft side of the fan (1). The water tank (7) deviates from the air draft path and is located under the adsorption module (6), wherein the adsorption module (6) is inserted from the outer casing (2), the top of the adsorption module (6) is fixed on the outer casing (2), and the bottom of the adsorption module (6) penetrates into the inner water surface of the water tank (7) to adsorb water or is higher than the water surface. Compared with humidifying and dehumidifying air conditioners in the prior art, the air conditioner can achieve the same humidifying and dehumidifying effects, but is obviously simple in structure and does not need an externally-connected water supply pipeline, so that the air conditioner has superiority.

The invention relates to a two-stage jet nozzles series super-magnetostrictive jet servo valve and an operating method thereof, which belong to the field of a hydraulic servo control technique. The two-stage jet nozzles series super-magnetostrictive jet servo valve provided by the invention comprises an upper end cover (4), a lower end cover (26), a super-magnetostrictive rod (14), an output rod (21), a coil skeleton (8), a polarization magnetic filed generating unit and a driving magnetic field generating unit, wherein the upper end cover (26) is provided with a left valve core installation cavity (45) and a right valve core installation cavity (46) which are symmetrical relative to the axis of the output rod; a group of valve core components are respectively installed in the left valve core installation cavity (45) and the right valve core installation cavity (46); and wedge-shaped amplification mechanisms are formed in the contact positions of the output rod (21) and the left and the right valve core installation cavities. The two-stage jet nozzles series super-magnetostrictive jet servo valve provided by the invention has the advantages of great pressure gain and rapid response, and the driving part has the obvious characteristics of small heat radiation, adjustable polarization magnetic filed, intelligentized effect and the like.

The invention discloses an optical fiber gyroscope with an optical fiber ring adopting a double-ring design. The optical fiber gyroscope comprises a light source, a photoelectric detector, an optical fiber coupling device, a signal processor, an optical modulator and an interference part, wherein the interference part comprises two optical fiber rings and a heat insulation device; the heat insulation device comprises an inner cavity and an outer cavity; a hard insulating ring is mounted between the inner cavity and the outer cavity; a heat guide groove is mounted in the inner cavity; the two optical fiber rings are symmetrically mounted on the two sides of the heat guide groove; a small hole is formed in the heat guide groove; corresponding ends of the two optical fiber rings are spliced and a splicing point is located in the small hole of the heat guide groove; leading-out ends of the two optical fiber rings are led out from other small holes of the heat guide groove and penetrate through the inner cavity and the outer cavity respectively; the leading-out end of one optical fiber ring is connected with a first output end of the optical modulator and the leading-out end of the other optical fiber ring is connected with a second output end of the optical modulator; and the small holes on the heat guide groove are sealed, and the inner cavity and the outer cavity are sealed. The optical fiber gyroscope has the advantages of high temperature stability.

The invention relates to the technical field of food processing equipment, and particularly discloses a sheet food processing device. The sheet food processing device comprises a drying cylinder, wherein the outer periphery of the drying cylinder is rotationally connected with a sleeve, a first cavity is formed between the sleeve and the drying cylinder, a plurality of hot air holes are formed inthe side wall of the drying cylinder, one end of the drying cylinder is provided with a feeding valve and a pressure release valve, and the sheet food processing device further comprises a hot fan; across shaft is rotationally connected in the drying cylinder, a second cavity is arranged in the cross shaft, and the other end of the cross shaft is connected with a heat conduction tube; and a plurality of cylindrical air bags are fixed on the cross shaft, first magnets are fixed on the circumferential inner walls of the air bags, springs are fixed between the first magnets and the cross shaft,second magnets are fixedly arranged on the sleeves below each air bag, and when the first magnets and the second magnets are close to each other, the first magnets and the second magnets attract eachother, air inlet one-way valves communicating with the second cavity and the air bags are arranged on the cross shaft, a plurality of exhaust holes are formed in the air bags, and an air outlet one-way valve is arranged in the exhaust holes. According to the sheet food processing device, hard bean curd is subjected to centrifugal, heating type and extrusion type dehydration, so that the hard beancurd is good in drying effect and high in efficiency.

The invention discloses an air-cooled module for heat transfer temperature uniformization of a fuel cell. The air-cooled module mainly consists of a fuel cell module, fins and a fan system; the fuel cell module comprises an end cap, a membrane electrode, an ultra-thin temperature uniformization plate, a plurality of membrane electrodes and a plurality of ultra-thin uniform temperature plates are alternately arranged, the two sides of each membrane electrode are respectively provided with an ultra-thin uniform temperature plate, and the ultra-thin uniform temperature plate comprises a shell, acavity, a liquid suction core and a working medium; The hollow cavity is arranged in the housing, the hollow cavity is at least protruded from one end of the housing, and the hollow cavity is providedwith a liquid suction core and a working medium; The upper surface or the lower surface of the shell is respectively provided with an air flow channel or a hydrogen flow channel; The overall thickness of the ultra-thin homogeneous temperature plate shall not exceed 3mm; A plurality of fins are installed on the condensing end of the ultra-thin uniform temperature plate. The evaporation end of theultra-thin uniform temperature plate of the invention can separate the reaction gas, collect and conduct the electric current; The heat flux concentrated on the surface of the bipolar plate is rapidlytransferred and diffused to the large area of the condensation surface, which has the effect of uniform temperature and heat dissipation.

A novel multi-capacitor divider network in which two capacitors are fabricated in a single package, using a common dielectric material, is disclosed. In a preferred embodiment of the present invention, the multi-capacitor network comprises a high-voltage capacitor and a low-voltage capacitor fabricated in a single monolithic package, both fabricated from a class one dielectric material having a combined tolerance of plus or minus five percent. The use of the same class one dielectric material for both capacitors assures that the temperature coefficents are similar for both capacitors and, more importantly, that the tolerance of the ratio between the high-voltage capacitor and low-voltage capacitor is within a predetermined range.

A tab lead soldering apparatus soldering a tab lead to a front face and a rear face of a solar cell has a first pressing mechanism pressing the tab lead toward the front face of the solar cell, a second pressing mechanism pressing the tab lead toward the rear face of the solar cell rear face, a heat member and a support member provided to the first pressing mechanism and / or the second pressing mechanism to contact with the tab lead, a heat member shift mechanism shifting the heat member between a contact position to contact an end of the heat member with the tab lead and a separation position to separate the end of the heat member from the tab lead, and a support member shift mechanism shifting the support member between a contact position to contact an end of the support member with the tab lead and a separation position to separate the end of the support member from the tab lead.

In a Czochralski process for growing single crystal silicon ingots, a system is provided for adding solid material to the liquid silicon during crystal growth for the purpose of directly controlling the latent heat of fusion with respect to a crystal melt interface. In contrast to the standard method for controlling power to the crucible heater, the present system has been found to be much more effective for controlling melt temperature in the crucible, especially in heavily insulated systems. The system provides the advantage of reducing the electric power required to operate a Czochralski grower, while increasing the speed with which the melt temperature can be raised or lowered in a controlled manner.

The invention discloses a vehicle rear combined lamp. The vehicle rear combined lamp comprises a lamp shell and a lens; the lens is tightly connected with the lamp shell, and includes an inner layer and an outer layer; a thermal insulating layer is arranged between the inner layer and the outer layer, and is a vacuum layer; a circulating device for forming internal circulation of gas in the lamp shell is arranged in the lamp shell, and includes a gas sucking pipe, a gas blowing pipe and a fan for connecting the two; a reflecting cup is arranged in the lamp shell, and is provided with a hole for passing through a light source; and the gas sucking pipe and the gas blowing pipe are both positioned in the hole of the reflecting cup, and are symmetrically arranged about the axis of the reflecting cup. The lens is set as two layers, so that the temperature difference of the inner and outer two sides of the lens is reduced, the fogging on the surface of the lens is prevented, and the influence on the effect of the lens by fog is prevented, and the driving safety is improved.

The invention discloses a waste heat hardening and tempering process of motorcycle crank forged piece, comprising the working procedures like medium-frequency heating, extracting billet, blocking, precise forging, isothermal processing, quenching, tempering and the like. The process can obviously improve hardenability through forging waste heat hardening and tempering, ensure even distribution of tissues and hardness and ensure that the forged piece has the mechanical performance superior to that of the workpieces after conventional hardening and tempering. The workpieces undergoing finish forging adopt short isothermal processing to ensure the temperature of the workpieces to be uniform when entering quenching liquid, thus ensuring stable performance and excellent quality and realizing industrial production. Meanwhile, the short isothermal processing only consumes little electric energy, thus conforming to the requirement of the economical society.

The invention relates to an ultralow loss optical fiber production system and a technology used for production. The ultralow loss optical fiber production system comprises a wire drawing device, an annealing device, a coating curing device, and a control unit A. The wire drawing device is a wire drawing furnace, which, from top to bottom, comprises a furnace top gas disc, a wire drawing furnace body, and a lower end annealing tube, which are in a coaxial arrangement. The annealing device is a heat preservation annealing furnace, and the coating curing device comprises a coating device and an ultraviolet light curing furnace, which are sequentially arranged. When the ultralow loss optical fiber is disposed in the production system, the optical fiber passes through the wire drawing device, the annealing device, the coating curing device, and the control unit A. The ultralow loss optical fiber production system and the technology used for the production are advantageous in that the wire drawing furnace top gas disc is provided with a plurality of gas inlets, and the original single heating element of the heat preservation annealing furnace is changed into an upper heating element and a lower heating element, which are independent from each other, and are controlled respectively by independent power supplies; the connection with the wire drawing furnace is realized by a data line, and then remote control is realized; the ultraviolet light curing furnace is used for on-line monitoring of a gas exhaust condition, and is used to adjust the gas exhaust condition automatically.

The invention discloses a stir-fry machine and a porridge cooking control method thereof. The stir-fry machine comprises a heating assembly, a cooking cavity and a stirring shovel extending into the cooking cavity, wherein the stirring shovel is used for turning over cooking food materials that are placed in the cooking cavity up and down. The porridge cooking control method comprises the steps: agradient type temperature rising stage: controlling the heating power of the heating assembly to heat in a gradient descending mode, and controlling the stirring shovel to turn over the cooking foodmaterials in a first rotating mode; and a boiling porridge cooking stage: controlling the heating power of the heating assembly to heat in an intermittent heating mode, and turning over the cooking food materials up and down by the stirring shovel in a second rotating mode until the cooking is finished. According to the invention, in the stirring process, the food is gelatinized, the viscosity ismoderate, the taste of a user is good, and the pot overflowing phenomenon in the porridge cooking process can be avoided by combining segmented and stepped heating with stirring.

The invention relates to a crystallization tank for traditional Chinese medicine extraction. The crystallization tank comprises a crystallization tank body and a crystal seed generation tank, wherein a tank cover is arranged on the crystallization tank body; a plurality of material addition ports are formed in the tank cover; a motor is arranged above the crystallization tank body and connected with a stirring shaft; a plurality of paddles are arranged on the stirring shaft; a first cooling jacket is arranged around the crystallization tank body; a discharge port is formed in the bottom of the crystallization tank body; a second cooling jacket is arranged around the crystal seed generation tank; a plurality of ultrasonic transducers are uniformly arranged on the outer wall of the second cooling jacket; a feeding port and a conveying port are formed in the top and the bottom of the crystal seed generation tank respectively; the conveying port is connected with a conveying pipeline, and the other end of the conveying pipeline extends into the upper part of the crystallization tank body. With the adoption of the crystallization tank for traditional Chinese medicine extraction, the quantity of added crystal seeds and the granularity can be effectively controlled, the controllability of the crystallization process is improved, the quality of produced traditional Chinese medicine crystals is good, the purity is high, the granularity is uniform, and convenience is brought for the following preparation process.

The invention relates to a hot-pressing sintering machine and a temperature uniformity control method thereof. The sintering machine comprises two electrodes, n temperature sensors and a temperature control device. The first electrode is divided into n electrode sections arranged in a mutual insulation mode, and n is larger than or equal to two. Each electrode section is connected with a corresponding power supply line and used for leading-in of an electric current, and thus the electric current flows among the corresponding electrode section, a mold and the second electrode. The temperature sensors are in one-to-one correspondence with the electrode sections and used for detecting the temperature of the corresponding electrode sections. The temperature control device is in sampling connection with the n temperature sensors and in control connection with all the power supply lines and used for correspondingly adjusting electric currents in the corresponding power supply lines according to collected temperature values. Temperature on the electrodes of all parts can be made to tend to equality, then temperature in a graphite mold is controlled and distributed uniformly, the condition of a nonuniform temperature field is eliminated, thus uniformity of performance of sintered products is ensured, and the quality of the sintered products is improved.

The invention discloses a heat-preserving shell provided with an LED (Light-Emitting Diode) lamp for a flowerpot. The heat-preserving shell comprises a cover body and a base, wherein the cover body has a bowl-shaped structure consisting of an inner wall and an outer wall, and is free from upper and lower surfaces; a gap is reserved between the inner wall and the outer wall; the inner wall is provided with ventilation holes; a vertical support rod is arranged on the upper edge of the cover body; an LED lamp and a second switch are arranged at the upper end of the support rod; a power supply, a control module, a temperature detection module, a resistive heater and a fan are arranged inside the base; a first switch is arranged outside the base; the resistive heater is arranged on the upper part of the fan; the air outlet of the fan faces upwards; the power supply is connected with the control module through the first switch; the control module is connected with the temperature detection module, the resistive heater and the fan respectively; the LED lamp is connected with the power supply through the second switch. The temperature detection module is provided, the resistive heater and the fan are started when the environmental temperature is lower than the growth temperature of plants, and blown hot air can surround the plants, so that more healthy growth of the plants is ensured.

An all-directional constant-temperature wine cellar with the sub-control adjustment function comprises a wine cellar body, a temperature and humidity control device, an air disperse device and a wine rack, wherein the temperature and humidity control device, the air disperse device and the wine rack are arranged in the wine cellar body, the wine rack is located in a wine storage space on the upper portion of the interior of the wine cellar body, an airflow circulating space is arranged in the wine storage space and between the wine rack and the inner wall of the wine cellar body, a plurality of partition plates are arranged inside the wine rack so that the interior of the wine rack is divided into a plurality of vertical wine storage channels, air holes for air circulation are formed in the walls of the wine rack and the partition plates, the air disperse device is arranged below the wine rack and is connected with the temperature and humidity control device, a plurality of air disperse holes are evenly distributed in the top surface of the air disperse device, and the air disperse device is further provided with an air disperse window which is arranged at the bottom of the wine storage space. According to the all-directional constant-temperature wine cellar with the sub-control adjustment function, constant-temperature and constant-humidity airflow circulation is formed in the wine storage space, so that it is guaranteed that the temperature and the humidity at any position in the wine storage space are the same.

The invention relates to a temperature difference measuring device of heating systems pertaining to the technical field of a temperature measuring device. The invention is mainly characterized by composing of a double end thermocouple and a signal conditioning circuit, the two connecting poles of the double end thermocouple are sealed together, assuring insulation and the same temperature; when in operation, both testing ends of the double end thermocouple adopt sealing fixing pedestal are respectively inserted into the inlet and outlet port of a customer heating pipe, both connecting ends are arranged close and are respectively wrapped insulated in thermal insulation material, temperature is assured the same at both the ends, after the double end thermocouple induces the temperature difference at the inlet and the outlet ports, a tiny voltage difference is generated at both ends of the thermocouple, the signal is amplified and displayed by a temperature difference amplifying circuit, the signal multiplies with the flow data acquired by a flowmeter sensor, the double end thermocouple is made of economic and universal thermocouple material copper constantan, the cost is low, the cost is only 1 / 5 of Pt1000 pairing thermocouple. The invention can also be applied to temperature difference measuring of adjacent fields.

The invention provides refrigerating equipment (1). A storage chamber located on the same layer of a box-shaped liner (10) is at least divided into a first storage chamber body (101) and a second storage chamber body (102). A vacuumizing cavity (11) can be formed in the first storage chamber body (101). In this way, the second storage chamber body (102) serves as a non-vacuum storage chamber body and can serve as a moisturizing storage chamber body and the like according to requirements, and various types of storage chamber bodies are provided for a user to select. In addition, the vacuum cavity (11) needs to be vacuumized through a vacuum pump (12). The vacuum pump (12) can be located inside or outside the first storage chamber body (101). An exhaust pipe (13) and / or a wire cable connected with the vacuum pump (12) can stretch out by means of the wall of the second storage chamber body (102), and the situation that pipelines and wires penetrate through the rear wall of the first storage chamber body (101) is avoided. In this way, the assembling difficulty is lowered, and the height limitation, caused by pipeline installation, of a vacuum storage unit in the first storage chamber body (101) can be eliminated.

The invention discloses an etching machine, wherein an etching groove, a flushing tank and a driving device are arranged in a chassis; a basket is connected to the driving device, a first rotary shaft and a second rotary shaft are arranged on the basket, and the driving device drives the basket to rotate around the first rotary shaft and drives the first rotary shaft to rotate around the second rotary shaft. The etching machine disclosed by the invention improves the corrosive uniformity and corrosive speed as well as the uniformity of backwashing and the flushing speed.

The invention provides a dynamic water amount adjustment method for laminar flow cooling of a medium-thickness plate and a wide and thick plate considering head-tail temperature deviation. The steel sheet temperature is detected dynamically according to a certain cycle period by considering the advancing speed of a steel sheet in laminar flow cooling, and the flow of the required cooling water is dynamically calculated according to the newly detected temperature; then, the group number N of valves with the opening degree being 100% and the valve opening degree K of the last group of flow adjustment valves are determined according to the flow, wherein the K is larger than or equal to zero and smaller than or equal to one; and the delay time delta t of flow adjustment is determined according to the valve group number. By means of the dynamic water amount adjustment method, it can be guaranteed that the head and the tail of the steel sheet can be the same in temperature after being cooled, uniformity of product performance is guaranteed, the situation that the head performance is qualified while the tail performance is unqualified, or the tail performance is qualified while the head performance is unqualified is avoided, and controversy about quality is avoided as much as possible.

The invention discloses a compound feed for feeding an ecological sea duck and a preparation method of the compound feed. The compound feed comprises main ingredients are comprise corn and rice. The compound feed for feeding the ecological sea duck further comprises auxiliary materials including high-mountain Tieguanyin tea leaves, Codonopsis pilosula, astragali radix, liquorice, hawthorn, fennel, dried tangerine or orange peel, cinnamon and sand ginger, wherein the weight ratio of the auxiliary materials to the main ingredients is 40 to 1000. The main ingredients are mixed and ground into duck acceptable powders; the auxiliary materials are mixed and ground into grains; and the main ingredients and the auxiliary materials are mixed to obtain the product. After a laying duck is fed by the compound feed for a period of time, the egg yield of the laying duck is obviously increased; VA (vitamin A) and VE (vitamin E) in the egg are greatly increased; the content of cholesterol is reduced; and the disease resistance, the appetite and the vitality of the laying duck are significantly improved. After a meat duck is fed by the compound feed for a period of time, the appetite and the vitality of the meat duck are obviously improved; the physique is significantly enhanced; VA and VE in the duck meat are largely increased; the content of cholesterol is reduced; the taste of the duck meat is fresher and tender; and the drug residue is lowered.

The invention relates to a protective tube for detecting a high-temperature tungsten-rhenium thermocouple, and belongs to the field of high-temperature tungsten-rhenium thermocouple detection or calibration. The protective tube comprises a protective tube, an etalon radiation test hole, an upper tungsten piece grating, a lower tungsten piece grating, a sealing ring and a flange, wherein one end of the protective tube is in a closed state, and the other end of the protective tube is in an opened state; the inner wall of the protective tube adopts a two-level stepped design; a thick area of a tube wall is a uniform temperature area and is also a temperature sensing area of a calibration thermocouple, and the other areas of the tube wall are non-uniform temperature areas; the etalon radiation test hole is formed on the tube wall on the bottom of the lower end of the protective tube, and the bottom of the lower end of the protective tube is contacted with the uniform temperature area; and the two groups of tungsten piece gratings are arranged in the non-uniform temperature areas, one group is arranged in the boundaries of the uniform temperature area and the non-uniform temperature areas, and the other group is arranged in the middle of the non-uniform temperature areas. The uncertainty of a calibration result is reduced to the maximum extent, so that calibration conditions of the high-temperature tungsten-rhenium thermocouple at 3000 DEG C and blow are greatly improved.

The invention discloses a high-entropy alloy preparation method and device based on laser cladding deposition. The method comprises the following steps: mixed powder A is prepared; the mixed powder Acomprises three, four, five or six in metal simple-substance powder of tungsten, niobium, molybdenum, tantalum, zirconium and rhenium; the atom number percentage of each metal element in the mixed powder A is within 5-35%; powder B is uniformly mixed in the obtained mixed powder A to obtain mixed powder C; the powder B comprises one or more in metal simple-substance powder of titanium, vanadium and hafnium; a substrate of the device for realizing the laser cladding deposition is preheated; and then, the laser cladding deposition method is used for molding the mixed powder C. Through mixing ofthe low-melting-point metal simple-substance powder of titanium, vanadium or hafnium, and meanwhile, through reduction of the temperature gradient between the substrate and a clad layer by preheating,the crack elimination and inhibition in the preparation of high-melting-point high-entropy alloys based on the laser cladding deposition can be achieved.

A sensor for determining a mass flow of a fluid in a pipe includes a wall element adapted for insertion into a cutout in a wall of the pipe through which a mass flow can flow, so that at least one gap remains between the wall element and the wall of the pipe, and so that the wall element is positionable on the outside facing away from the mass flow. A sealed chamber is adapted to enclose the wall element on the outside of the pipe. At least one expandable connection is located in the sealed chamber and is clamped in between the wall element and one wall of the chamber. At least one strain gauge comprising a fiber Bragg grating sensor is located on a section of the expandable connection that is clamped in between the wall of the chamber and the wall element.

The invention discloses an integral low-frequency microwave dehydration method for large-sized food. The method comprises the following steps of: preprocessing and draining food to be dehydrated; filling in a 915 MHz low-frequency microwave vacuum drying device ; drying until the water content is 65-55 percent under the conditions of pressure of 30 kPa and microwave loading power of 2.0 W / g; increasing the pressure of a drying cabin to 60 kPa, reducing the microwave loading power to 1.2 W / g and drying until the water content is 35-25 percent; and finally, recovering the pressure of the dryingcabin to 30 kPa, reducing the microwave loading power to 0.5 W / g and drying until the final water content is 7 percent. By using the low-frequency microwave sectional drying method, the drying speed is increased, the drying time is shortened, the risk of deterioration of nutrient components in the food in a drying period is reduced, meanwhile, the structure and the nutrient components in the foodare not damaged yet, and the deformation of appearance of the food is small after the drying is finished.