34results about How to "Low technical requirements for production" patented technology

The invention discloses a stent for osteochondral defect repair. The stent consists of a cartilage layer with pores and a subchondral bone layer with pores, wherein the cartilage layer and the subchondral bone layer are tightly combined into a whole; the material of the cartilage layer is a mixture of type I collagen and chondroitin sulfate; and the material of the subchondral bone layer is porous titanium or porous titanium oxide or a porous titanium alloy. A preparation method of the stent comprises the following steps of: (1) processing the porous titanium or porous titanium oxide or porous titanium alloy to a shape and a size required by the subchondral bone layer; (2) preparing cartilage layer slurry; and (3) molding and treating a stent, putting the subchondral bone layer prepared in the step (1) into a mold, injecting the cartilage layer slurry prepared in the step (2) into the mold, putting the mold into a freeze dryer, freezing for at least 5 hours, molding, performing thermal crosslinking and chemical crosslinking on the molded stent, and putting the chemically-crosslinked stent into sterile water for rinsing to obtain the stent for osteochondral defect repair.

The invention discloses polyester modified hydroxyl type fluorinated acrylate resin and a preparation method thereof. On the basis of double-bond hydroxyl type polyester, (methyl) acrylics, (methyl) fluorinated acrylics, (methyl) acrylic acid and hydroxyl (methyl) acrylate monomers are subjected to graft copolymerization through solution polymerization, and hybridization of fluorinated acrylate resin and polyester resin is realized; and during preparation of fluorine resin, the polyester resin is introduced creatively to perform hybridizing modification on the fluorine resin, features of the fluorine resin are kept while the cost of the fluorine resin is reduced, meanwhile, the solid content is higher, and the resin has the better environmental protection performance. Used synthetic raw materials are common raw materials, the requirements for a production technology are not high, the synthesis cost of the fluorine resin is low, the performance of 2KPU (two-component polyurethane) varnish prepared with the fluorine resin is excellent, and prepared coatings are applicable to various base materials such as wood products, metals, plastics, concrete and the like.

The invention discloses a fibroblast liquid for beauty treatment and a preparation method thereof. The fibroblast liquid contains a cell culture solution, collagens, cell growth factors, amino acids and vitamins, wherein the cell growth factors comprise fibroblast growth factors, epidermal cell growth factors, hepatocyte growth factors and keratinocyte growth factors. The preparation method of the fibroblast liquid comprises the following steps: acquiring umbilical cord tissue hypodermal cells, carrying out primary culture of the umbilical cord tissue hypodermal cells, subcultring the umbilical cord tissue hypodermal cells, collecting the obtained cell culture liquid, and adding glycerin and cytokines to prepare the fibroblast liquid. The fibroblast liquid has the efficacies of epidermal cell metabolism promotion, skin elasticity enhancement, injured epidermal cell restoration, color spot removal and the like; and the preparation method is simple, is easy to operate, and is suitable for the large-scale growth preparation of stem cell liquids.

The invention belongs to the field of inorganic compound semiconductor materials, in particular relates to a method for efficiently preparing GaN nanocrystals by utilizing a CNT (Carbon Nano Tube). The method comprises the steps of firstly, uniformly grinding and mixing gallium salt and an acidified CNT; then, adding the mixture into a solution prepared from water and polyhydric alcohol; carrying out ultrasonic dispersion under a heating condition; putting a filtered and dried mixture into a tubular furnace; decomposing the filtered and dried mixture under 300 to 500 DEG C of air atmosphere to obtain a porous Ga2O3 and CNT composite material; pumping a protective nitrogen gas in the tubular furnace; rising the temperature to be 750 to 1000 DEG C; replacing the nitrogen gas with an ammonia gas to react for 40 to 80 minutes; stopping pumping the ammonia gas in the nitrogen atmosphere, cooling to room temperature and obtaining light-yellow GaN nanocrystals. According to the method disclosed by the invention, the contact area between the porous Ga2O3 and CNT composite material and NH3 is enlarged by utilizing the porosity of the porous Ga2O3 and CNT composite material, so that NH3 can diffuse and enter Ga2O3 particles for nitridation, the reaction speed is quickened, the reaction temperature is reduced, and prepared GaN nanoparticles are high in yield and purity.

The present invention belongs to the field of semiconductor materials, and in particular relates to a low-cost method for preparing a gallium nitride crystal. According to the method, a high temperature resistant inorganic mineral with a layered structure is used as a template, a surfactant and a metal complexing agent are used for modifying the inorganic layered mineral, and gallium ions are adsorbed uniformly in the layered structure of the inorganic mineral; the layered structure of the inorganic mineral is used as a gallium source precursor, and is placed in a quartz crucible to put into a tube furnace for reaction for 1-3h under a 250-400 DEG C air atmosphere, tube furnace temperature is raised to 800-1000 DEG C, ammonia gas is introduced into the tube furnace for reaction for 1-2h, an obtained crude product is washed with an acid to obtain a large-size pale yellow gallium nitride crystal in a regular crystal form. A confinement space between the layers of the inorganic mineral is used, so that the gallium nitride crystal grows along a gap of the layered structure, the layered structure confinement space has a certain thermal insulation effect, and can reduce the reaction temperature and improve reaction time. The cost is low, and the method is suitable for mass production.

The invention relates to the field of fasteners, in particular to an inner hexagon screw fastener which comprises an inner hexagon screw head. The inner hexagon screw head comprises an end head body and a No.1 inner hexagon slot; the No.1 inner hexagon slot is formed in one side surface of the end head body; a first section is perpendicularly connected onto one side surface, far away from the No.1inner hexagon slot, of the end head body; the first section is connected with a third section through a second section; an end section is connected to one end, far away from the second section, of the third section; and one end, far away from the third section, of the end section is connected with the third section through a reinforced screw. According to the inner hexagon screw fastener providedby the invention, by additionally arranging the second section, the third section and the end section in threaded connection, the effective length of the screw is extended; and in addition, through the connection manner, the length can be adjusted at will, and the occurrence of the phenomena of joint weakness, unevenness and damage caused to the screw is avoided, so that the application range andthe use convenience of the inner hexagon screw fastener provided by the invention are greatly improved.

The invention discloses a fibroblast liquid for beauty treatment and a preparation method thereof. The fibroblast liquid contains a cell culture solution, collagens, cell growth factors, amino acids and vitamins, wherein the cell growth factors comprise fibroblast growth factors, epidermal cell growth factors, hepatocyte growth factors and keratinocyte growth factors. The preparation method of the fibroblast liquid comprises the following steps: acquiring umbilical cord tissue hypodermal cells, carrying out primary culture of the umbilical cord tissue hypodermal cells, subcultring the umbilical cord tissue hypodermal cells, collecting the obtained cell culture liquid, and adding glycerin and cytokines to prepare the fibroblast liquid. The fibroblast liquid has the efficacies of epidermal cell metabolism promotion, skin elasticity enhancement, injured epidermal cell restoration, color spot removal and the like; and the preparation method is simple, is easy to operate, and is suitable for the large-scale growth preparation of stem cell liquids.

The invention discloses a face cleaning composition with the moisture-preserving function and the skin whitening function and a preparing method thereof. The face cleaning composition is prepared from soybean extract freeze-dried powder, sodium cocoyl glutamate, sodium lauroyl glutamate, bromelain, lipase, dipotassium glycyrrhizinate, pearl powder and chitosan oligosaccharide. The preparing method includes the following steps that 1, raw material soybeans are shelled to be prepared into water slurry and homogenized, (NH4)2SO4 is added, proteins settled when the concentration of the (NH4)2SO4 is larger than 40% and smaller than or equal to 50% are centrifugally collected, emulsion is obtained after concentration, freeze drying is carried out on the emulsion, and the soybean extract freeze-dried powder is obtained and sterilized; 2, the other components are added into the sterilized soybean extract freeze-dried powder according to the quantity of the formula, and the face cleaning composition is prepared. The face cleaning composition is weakly acidic, the skin surface lipid film of the human body is not injured, and the effects of cleaning the skin, locking water, preserving moisture and whitening the skin are further achieved; the preparing method of the face cleaning composition is free from a traditional chemical production adding technology, and the raw materials are natural.

The invention belongs to the field of inorganic compound semiconductor materials, and more particularly relates to a preparation method for improving the quality of gallium nitride crystals. The preparation method comprises the following steps: firstly, dispersing metal gallium salt and a nucleation inducer in a polyvinyl alcohol water solution, adding a water-based adhesive and stirring at a high speed, such that the gallium salt and the nucleation inducer are coated in a gel network structure formed from polyvinyl alcohol; then carrying out high-pressure homogenization to form nano composite gel; uniformly coating the obtained composite gel onto an Si substrate subjected to surface treatment; putting the Si substrate in a tube furnace and drying in a nitrogen atmosphere, and then raising the temperature of the tube furnace to 850 to 1050 DEG C; introducing ammonia to react for 90 to 110min; stopping introducing the ammonia and cooling to room temperature in the nitrogen atmosphere to obtain faint yellow gallium nitride crystals having a regular crystal form. According to the preparation method, the gallium nitride crystals are prepared by coating the composite nano gel formed by the gallium salt and the nucleation inducer onto the Si substrate, such that the gallium nitride crystals are good in surface appearance, regular in crystal form, high in yield and high in purity and have a wide application value.

The invention discloses a drinking bottle with a ventilation structure, and belongs to the field of bottles. The drinking bottle comprises a bottle body and a bottle cover, wherein the bottle cover comprises an air inlet for air intake and a drinking suction nozzle for sucking beverages; the ventilation structure is arranged inside a cavity of the bottle body; the ventilation structure comprises a soft silica gel tube and a hollow floating ball; one end of the soft silica gel tube communicates with and is connected to the air inlet, and the other end of the soft silica gel tube communicates with and is connected to the hollow floating ball; more than one air outlet, which communicates with the air inlet, are arranged at the top of the hollow floating ball; and a vent check valve is arranged on each air outlet. By virtue of the ventilation structure which is added inside the bottle body, air inside the bottle body basically communicates with external atmosphere, so that the beverages can be drunk more easily and babies can feel easier to suck the beverages; compared with a conventional structure which is arranged on a bottle cover and simultaneously serves as a valve body, the drinking bottle has lower requirement on production technology and lower manufacturing cost; and by arranging the vent check valve inside the bottle body, any phenomenon that liquid inside the bottle body flows back is avoided.

The invention relates to a method for preparing adipose-derived stem cell sap for cosmetic maintenance and belongs to the technical field of medical beauty. The method includes step 1 of obtaining adipose-derived stem cells; step 2 of subculture; step 3 of low temperature freezing; and step 4 of preparation of the adipose-derived stem cell sap. The method for preparing the adipose-derived stem cell sap is simple and convenient to operate, the production technology requirements are not high, the method is suitable for large-scale production of cell sap products, the production process can be developed for a long time in a large scale in a biotechnology production workshop, the manufacturing cost is low, the product effect is very good, the retention time of the adipose-derived stem cell sapcan be prolonged through the low temperature freezing step, a frozen state is removed when the adipose-derived stem cell sap needs to be used, and the market prospect is broad.

The invention belongs to the field of inorganic compound semiconductor materials, in particular relates to a method for efficiently preparing GaN nanocrystals by utilizing a CNT (Carbon Nano Tube). The method comprises the steps of firstly, uniformly grinding and mixing gallium salt and an acidified CNT; then, adding the mixture into a solution prepared from water and polyhydric alcohol; carrying out ultrasonic dispersion under a heating condition; putting a filtered and dried mixture into a tubular furnace; decomposing the filtered and dried mixture under 300 to 500 DEG C of air atmosphere to obtain a porous Ga2O3 and CNT composite material; pumping a protective nitrogen gas in the tubular furnace; rising the temperature to be 750 to 1000 DEG C; replacing the nitrogen gas with an ammonia gas to react for 40 to 80 minutes; stopping pumping the ammonia gas in the nitrogen atmosphere, cooling to room temperature and obtaining light-yellow GaN nanocrystals. According to the method disclosed by the invention, the contact area between the porous Ga2O3 and CNT composite material and NH3 is enlarged by utilizing the porosity of the porous Ga2O3 and CNT composite material, so that NH3 can diffuse and enter Ga2O3 particles for nitridation, the reaction speed is quickened, the reaction temperature is reduced, and prepared GaN nanoparticles are high in yield and purity.

The invention discloses a drinking bottle with a ventilation structure, and belongs to the field of bottles. The drinking bottle comprises a bottle body and a bottle cover, wherein the bottle cover comprises an air inlet for air intake and a drinking suction nozzle for sucking beverages; the ventilation structure is arranged inside a cavity of the bottle body; the ventilation structure comprises a soft silica gel tube and a hollow floating ball; one end of the soft silica gel tube communicates with and is connected to the air inlet, and the other end of the soft silica gel tube communicates with and is connected to the hollow floating ball; more than one air outlet, which communicates with the air inlet, are arranged at the top of the hollow floating ball; and a vent check valve is arranged on each air outlet. By virtue of the ventilation structure which is added inside the bottle body, air inside the bottle body basically communicates with external atmosphere, so that the beverages can be drunk more easily and babies can feel easier to suck the beverages; compared with a conventional structure which is arranged on a bottle cover and simultaneously serves as a valve body, the drinking bottle has lower requirement on production technology and lower manufacturing cost; and by arranging the vent check valve inside the bottle body, any phenomenon that liquid inside the bottle body flows back is avoided.

The invention belongs to the field of inorganic compound semiconductor materials, and more particularly relates to a preparation method for improving the quality of gallium nitride crystals. The preparation method comprises the following steps: firstly, dispersing metal gallium salt and a nucleation inducer in a polyvinyl alcohol water solution, adding a water-based adhesive and stirring at a high speed, such that the gallium salt and the nucleation inducer are coated in a gel network structure formed from polyvinyl alcohol; then carrying out high-pressure homogenization to form nano composite gel; uniformly coating the obtained composite gel onto an Si substrate subjected to surface treatment; putting the Si substrate in a tube furnace and drying in a nitrogen atmosphere, and then raising the temperature of the tube furnace to 850 to 1050 DEG C; introducing ammonia to react for 90 to 110min; stopping introducing the ammonia and cooling to room temperature in the nitrogen atmosphere to obtain faint yellow gallium nitride crystals having a regular crystal form. According to the preparation method, the gallium nitride crystals are prepared by coating the composite nano gel formed by the gallium salt and the nucleation inducer onto the Si substrate, such that the gallium nitride crystals are good in surface appearance, regular in crystal form, high in yield and high in purity and have a wide application value.

The invention discloses a face cleaning composition with the moisture-preserving function and the skin whitening function and a preparing method thereof. The face cleaning composition is prepared from soybean extract freeze-dried powder, sodium cocoyl glutamate, sodium lauroyl glutamate, bromelain, lipase, dipotassium glycyrrhizinate, pearl powder and chitosan oligosaccharide. The preparing method includes the following steps that 1, raw material soybeans are shelled to be prepared into water slurry and homogenized, (NH4)2SO4 is added, proteins settled when the concentration of the (NH4)2SO4 is larger than 40% and smaller than or equal to 50% are centrifugally collected, emulsion is obtained after concentration, freeze drying is carried out on the emulsion, and the soybean extract freeze-dried powder is obtained and sterilized; 2, the other components are added into the sterilized soybean extract freeze-dried powder according to the quantity of the formula, and the face cleaning composition is prepared. The face cleaning composition is weakly acidic, the skin surface lipid film of the human body is not injured, and the effects of cleaning the skin, locking water, preserving moisture and whitening the skin are further achieved; the preparing method of the face cleaning composition is free from a traditional chemical production adding technology, and the raw materials are natural.

The present invention belongs to the field of semiconductor materials, and in particular relates to a low-cost method for preparing a gallium nitride crystal. According to the method, a high temperature resistant inorganic mineral with a layered structure is used as a template, a surfactant and a metal complexing agent are used for modifying the inorganic layered mineral, and gallium ions are adsorbed uniformly in the layered structure of the inorganic mineral; the layered structure of the inorganic mineral is used as a gallium source precursor, and is placed in a quartz crucible to put into a tube furnace for reaction for 1-3h under a 250-400 DEG C air atmosphere, tube furnace temperature is raised to 800-1000 DEG C, ammonia gas is introduced into the tube furnace for reaction for 1-2h, an obtained crude product is washed with an acid to obtain a large-size pale yellow gallium nitride crystal in a regular crystal form. A confinement space between the layers of the inorganic mineral is used, so that the gallium nitride crystal grows along a gap of the layered structure, the layered structure confinement space has a certain thermal insulation effect, and can reduce the reaction temperature and improve reaction time. The cost is low, and the method is suitable for mass production.

The invention discloses a power loss recycling device. The power loss recycling device comprises a driving device and an energy storing device. The driving device comprises a power gear I, a primary drive shaft, a shifting slide gear II, a gear III, a gear IV and a gear V. The energy storing device comprises a secondary drive shaft, a gear VI, a gear VII, a roller, a rolling-sheet-type spring and a braking pad. The driving device cooperates with the energy storing device to transmit kinetic energy. By the aid of transmission among gears and power storage and release of the rolling-sheet-type spring, mutual transformation between kinetic energy and elastic potential energy can be realized; when motor vehicles need to be slowed down or stopped, kinetic energy of the running motor vehicles can be transformed into elastic potential energy to be stored; and elastic potential energy can be used when motor vehicles are started or sped up, so that energy conservation can be achieved and security assurance can be improved.

The invention discloses a split assembled internal single cover diesel rear cover breather which comprises a rear cover plate, a gas discharging element and a breather body. The breather body is arranged in an inner cavity of the rear cover plate, the breather body and the gas discharging element are fixed to the rear cover plate in a sealed mode through detachable structures, the gas discharging end of the gas discharging element is arranged on the outer side of the rear cover plate, and a gas exchange cavity in the breather body is communicated with the outside through the gas discharging element. Meanwhile, the invention discloses several typical structures of the breather and installation methods of the breather, the defects of the prior art are overcome, the negative pressure value of the breather can stably reach the height of a 19.5 cm water column or higher, the structure of an internal rear cover breather part is simplified, the use stability and reliability of the breather are improved, a welding sealing structure in the prior art is eliminated, an existing welding fixing structure is replaced by a split assembling structure, part production is facilitated, assembling is also facilitated, the first pass yield of product production is increased, the production cost can also be greatly reduced, and the requirement for production technologies is lowered.

The invention discloses an aqueous gel chromatography medium. The aqueous gel chromatography medium is composed of polysucrose, gelatin and water, wherein the concentration of polysucrose is 5-100g / L, and the concentration of gelatin is 1-10g / L , The aqueous gel chromatography medium can separate red blood cells and free immunoglobulins for the detection of incomplete antibodies and separate particulate antigens and antibodies for the detection of antigens and antibodies. Through the above method, the aqueous gel chromatography medium of the present invention and the method for detection can be applied to the detection of blood cells such as red blood cells, platelets, and white blood cells, and can also be used for other particulate antigens and free antigens in immunolabeling techniques. The separation of soluble proteins, such as ELISA, immunofluorescence, flow cytometry, etc., avoids the cumbersome washing process in the operation of immunological methods, greatly simplifies the operation steps, improves the detection efficiency, and can be used for the detection of a large number of samples. Water-based The raw materials of the gel chromatography medium are cheap, and the production technology requirements are low.

The invention discloses a thermostat for household electrical appliances and an assembly method thereof, and relates to a thermostat. The key points of the technical solution include a casing with a temperature control element installed inside, a temperature-sensing cover fixed on the casing, and a thermostat. Mounting seat; wherein, the temperature-sensing cover is provided with an outer edge which is polygonal and arranged around the outer wall of the temperature-sensing cover, and the outer wall of the outer edge is provided with a ring of grooves arranged circumferentially on the outer wall of the temperature-sensing cover. The middle position of the mounting seat is provided with a through hole that is equal in size to the shape of the outer edge; among them, when the mounting seat and the temperature sensing cover are rotated and snapped together, stamping holes are used to clamp and fix the mounting seat at each corner of the outer edge The pinch point; the present invention has the effect of ensuring the connection strength between the installation base and the temperature-sensing cover.

The invention belongs to the technical field of agricultural domestic sewage treatment and particularly relates to tide current constructed wetland substrate packing for deep treatment of rural domestic sewage. The tide current constructed wetland substrate packing comprises three layers of substrate structures, wherein universal type substrates are adopted in the upper layer structure and the lower layer structure, and a nitrogen preference type substrate and a phosphor preference type substrate are adopted in the middle layer structure. The universal type substrates comprise coarse sand and gravel. The nitrogen preference type substrate comprises zeolite and an organic carbon source obtained through alkali heating. The phosphor preference type substrate comprises vermiculite, limestone and coal ash residues. The height of the upper layer structure ranges from 10 cm to 20 cm. The height of the middle layer structure ranges from 40 cm to 100 cm, and the mixed material of vermiculite and zeolite which are equal in size and the mixed material of limestone, coal ash residues, zeolite and the organic carbon source obtained through alkali heating which are equal in size are arranged from top to bottom in sequence, wherein the height of the mixed material of vermiculite and zeolite ranges from 20 cm to 55 cm, and the height of the mixed material of limestone, coal ash residues, zeolite and the organic carbon source obtained through alkali heating ranges from 20 cm to 45 cm. The height of the lower layer structure ranges from 10 cm to 20 cm. The tide current constructed wetland substrate packing is capable of treating various pollutants in the sewage at the same time, stable in operation, not likely to cause blockage, economical and efficient.

The invention discloses a stent for osteochondral defect repair. The stent consists of a cartilage layer with pores and a subchondral bone layer with pores, wherein the cartilage layer and the subchondral bone layer are tightly combined into a whole; the material of the cartilage layer is a mixture of type I collagen and chondroitin sulfate; and the material of the subchondral bone layer is porous titanium or porous titanium oxide or a porous titanium alloy. A preparation method of the stent comprises the following steps of: (1) processing the porous titanium or porous titanium oxide or porous titanium alloy to a shape and a size required by the subchondral bone layer; (2) preparing cartilage layer slurry; and (3) molding and treating a stent, putting the subchondral bone layer prepared in the step (1) into a mold, injecting the cartilage layer slurry prepared in the step (2) into the mold, putting the mold into a freeze dryer, freezing for at least 5 hours, molding, performing thermal crosslinking and chemical crosslinking on the molded stent, and putting the chemically-crosslinked stent into sterile water for rinsing to obtain the stent for osteochondral defect repair.

The invention discloses a method for preparing a gallium nitride crystal by utilizing the solid-state displacement reaction. The method mainly comprises the following steps: (1) reaction precursors of gallic acid lithium and boron nitride are mixed and pre-pressed into a block, or pre-pressed into sheets respectively, and the sheets are alternately piled into a block; (2) a block reactant which are obtained by the pre-pressing after mixing or alternate piling is put in a high-pressure synthesis block; (3) the assembled high-pressure synthesis block is placed in a synthesis cavity of a large presser for the solid-state displacement reaction, the synthesis temperature is not less than 850 DEG C, the pressure is not less than 1.0GPa, and the synthesis time is not less than 1.0 minute; and (4) after the displacement reaction, the reactant is subjected to cooling and pressure relief, and the synthesis product is taken out and soaked in acid liquor to dissolve and remove LiBO2, and the gallium nitride crystal is obtained. The method has the advantages of low raw material cost, low requirement on production specification, convenient operation, high growth rate of crystal, short synthesistime, easy popularization, mass production and the like.

The invention discloses an antenna. The antenna is integrally formed by etching on a module PCB, and comprises a wifi antenna and a Bluetooth antenna. Compared with the prior art, in the manufacturing material process, most of common iron antennas in the market are made of stainless steel and are pressed and formed through a specific mold, and the antenna is formed by etching a copper sheet on a copper-clad plate with the thickness of 40 microns; in the use mode, the iron antenna needs to be welded on the module or externally connected with a tinned copper wire and an IPEX seat and then buckled on the module for use in the later use period, the technical scheme can be designed in the module PCB and is integrally etched and formed, the production cost of materials is reduced, the corrosion resistance is good, an antenna mold does not need to be opened, and sample manufacturing and batch production are convenient; and the shape of the antenna is exposed and etched on the board by a machine according to a drawing so that the difference between finished product individuals is small, the requirement on the production technology is not high, the cost is low, and the production efficiency is high.

The invention belongs to the field of inorganic compound semiconductor materials, in particular to a method for preparing gallium nitride nanocrystals by using a twin-screw extruder. Firstly, the metal gallium salt is dissolved in the water-soluble polymer aqueous solution to form a slurry, and the slurry is pumped into the twin-screw extruder, and the slurry passes through the dispersing screw element, so that the gallium salt is coated on the hydrogel network formed by the water-soluble polymer In the structure, the water-soluble polymer is carbonized under shear and high temperature conditions to form a gallium salt covered by a carbon network structure; thermoplastic glue is added through the auxiliary material port, and the mixing reaction is extruded to form a thin sheet; the thin sheet is placed in a tubular After drying in the furnace, raise the temperature of the tube furnace to 900-1200°C, pass through the ammonia gas for 120-150 minutes, stop the flow of ammonia gas and cool to room temperature in an argon atmosphere to obtain a light yellow nitride with regular crystal form. gallium nanocrystals. The gallium nitride crystal prepared by the invention has good surface appearance, regular crystal form, high yield and high purity, and has wide application value.