41results about How to "Promote nucleation growth" patented technology

The invention discloses a preparation method for a hybrid composite coating used for magnesium-based biological material surface medication. The preparation method mainly comprises the following steps: A, grinding and polishing a magnesium-based biological material, cleaning the magnesium-based biological material, and vacuum-drying the magnesium-based biological material; B, soaking the magnesium-based biological material into a NaOH solution for 6-12 hours to obtain an alkaline-activated magnesium-based biological material; C, mixing a (NH4)2TiF6 solution with a H3BO3 solution to prepare an inorganic mixed solution with a pH being 2.7-2.9; preparing an organic solution with concentration being 2-10g/L, and regulating the pH value of the organic solution to 5-6, wherein the organic solution is a solution of phosphonic substances; D, soaking the magnesium-based biological material into the organic solution, and preserving the heat for 10-20 minutes at a temperature being 30-40 DEG C; E, soaking the magnesium-based biological material into the inorganic mixed solution, and preserving the heat for 30-40 minutes at a temperature being 45-55 DEG C; and F, repeating steps D and E for 1-10 times, thereby obtaining the hybrid composite coating. The coating prepared by the preparation method is good in binding force with the magnesium-based biological material, so that corrosion resistance and mechanical property of the magnesium-based biological material are improved, and therefore, the coating has very good biocompatibility; and the preparation method is gentle in preparation condition and is simple and controllable in process.

The invention provides a preparation method of scandium nitride cubic crystals, belonging to the technical field of preparation of a rare earth nitride nanometer material. The prepared scandium nitride cubic crystal comprises a regular cube or cuboid which has a flat and smooth surface and is uniform in appearance and dimension. With the adoption of the preparation method, the high-purity rare earth metal is directly reacted with nitrogen through a direct current arc plasma discharging device under the assistance of a high-temperature low-air pressure system condition and plasma, so as to prepare into powder with metallic luster and showing bluish green. According to the preparation method provided by the invention, the direct current arc plasma discharging device is utilized at the first time to synthesize scandium nitride cubic crystal which has high impurity and is uniform in appearance and dimension; the preparation method is simple, reliable, high in repeatability, short in reaction time, low in energy consumption, needs no the harsh vacuum condition, is environment-friendly, and has high output of products; and the scandium nitride cubic crystal has outstanding physical properties such as electricity, mechanics and the like, thus the scandium nitride cubic crystal can be widely applied in the fields of semiconductor devices and durable protecting coating and the like.

The invention belongs to the technical field of photocatalysts, in particular to an ultrasonic chemical in-situ preparation method for phthalocyanine-sensitized vanadate nano-powder. The method comprises the following steps specifically: dissolving a bismuth-containing reactant A in 2 to 5 mol/L acidic diluting agent to obtain a reaction liquid A; dissolving a vanadate-containing reactant B in distilled water to obtain a reaction liquid B of which the concentration is the same as that of the reaction liquid A; adding phthalocyanine serving as a sensibilizer into the reaction liquid A; adjusting the pH value of the solution to be between 1 and 4 by using an alkaline diluting agent; adjusting the temperature of the reaction liquid A to be between 50 and 95 DEG C; holding the temperature for 2 to 4 hours; adding the reaction liquid B into the reaction liquid A dropwise; and performing an ultrasonic reaction on the mixed liquid for 2 to 4 hours to obtain a product. The bismuth vanadate photocatalyst prepared by the method has the characteristics of good uniformity and higher photocatalytic activity.

This invention involves a kind of stannic oxide microballoon with controllable crystallite dimension and its preparation method and application. This stannic oxide microballoon is composed of stannic oxide microcrystal with fine crystallinity through self-assembly. The grain size of stannic oxide microcrystal is adjustable within range of 5-30nm. The diameter of stannic oxide microballoon is 200-400nm and its specific surface area >40m2/g; During preparation, add concentrated hydrochloric acid and tin source into the mixed solution of normal propyl alcohol and water in order, forming the transparent homogeneous solution; Conduct solvothermal reaction; After the reaction ends, take out the sediment, wash and separate it. Being compared with the current technology, this invention has simple and easy process route, which does not need surface active agent. And the multilevel structure Sno2 microballoon with equally distributed dimension can be gotten through one-step method, which is composed of stannic oxide microcrystal through self-assembly. Also, the dimension of Sno2 microcrystal can be adjusted and controlled through adjusting the alcohol/water proportion in the reaction system. The microballoon has features of high specific area and submicron level dimension, which has wide application prospect in areas of solar cell, lithium ion battery and photocatalysis.

The invention relates to a method for preparing a composite ultrafiltration membrane, and belongs to the technical field of water treatment. The composite ultrafiltration membrane is prepared by a sol-gel method. Silica and titanium dioxide are added to a casting solution, and the phase splitting process in the film formation process is controlled by means of the unique chain structure of the silica and the hydroxyl group on the surface thereof. The blending of nano titanium dioxide and a membrane material can enhance the hydrophilicity of the membrane, increase the membrane flux, improve theroughness of the membrane surface, delay membrane fouling, prolong the service life of the membrane, and reduce the operating cost of the membrane device. The porosity of the composite ultrafiltrationmembrane is gradually increased, and the water flux is gradually increased. A hydrogen bond may also be formed between polyvinylidene fluoride and cellulose micro/nano crystal, which enables the cellulose micro/nano crystal to be uniformly dispersed in a polyvinylidene fluoride solution, and have good interface bonding with the polyvinylidene fluoride, so that the composite membrane has certain strength and toughness, and thus the composite membrane exhibits good mechanical properties.

The invention discloses a polysilicon ingot furnace with a diversion device. The polysilicon ingot furnace comprises a heat insulation cage, a gas pipe and a diversion device. The diversion device is equipped with multiple diversion airways used for dividing input carrier gas into multiple outgoing carrier gas flows. The carrier gas flows are dispersedly and slantly blown to different areas on the surface of liquid silicon, thus effectively increasing contact area of the carrier gas and the surface of liquid silicon and minimizing heat per unit area by carrier gas flow. Thermal drop of liquid silicon in the area is reduced, degree of supercooling is decreased, and impurity nucleation and impurity formation caused by carrier gas are reduced. The outgoing carrier gas flows produce carrier gas stress to liquid silicon so as to drive liquid silicon to flow and to form a rotary flow field for circumferential flow. The rotary flow field is beneficial to transportation and uniform distribution of impurities in liquid silicon. An observation window at the top of the furnace has a field of view leading to the ingot furnace via the diversion device. Through the observation window, state inside the furnace can be observed, and a crystal measurement rod is inserted into the furnace. An infrared detector can detect the state of silicon materials inside the furnace, and the automatic crystal growth process is smoothly carried out.

The invention relates to a preparation method of photo-thermal response drug sustained-release hydrogel based on magnetic cellulose nanocrystals. The preparation method comprises the following steps:(1) preparing a CNC solution from plant raw materials by using an acid hydrolysis method; (2) introducing iron ions with different valence states into the CNC solution, and synthesizing magnetic nanoparticles in situ under an alkaline condition to obtain a colloidal solution; and (3) adding a polymer monomer, an initiator, a cross-linking agent and a catalyst into the colloidal solution obtained in the step (2), and reacting to obtain the target product. Compared with the prior art, the CNC solution is taken as a raw material, in-situ growth of the magnetic nanoparticles is taken as a basis, and different types of polymers with different contents are added, so that preparation of photo-thermal response drug-loaded hydrogel and light-operated drug release can be realized.

The invention provides an epitaxial structure of a light-emitting diode and a preparation method of the epitaxial structure, relates to the technical field of diodes, and is applied to a miniature light-emitting diode or an ultraviolet light-emitting diode. The epitaxial structure of the light-emitting diode comprises a substrate, a buffer layer and an epitaxial layer; the buffer layer is arranged between the substrate and the epitaxial layer, the buffer layer sequentially comprises a first buffer layer, a composite buffer layer and a second buffer layer, the first buffer layer is arranged on the substrate, the first buffer layer is made of metal Ni, and the first buffer layer grows in a PVD sputtering mode to form a metal Ni thin film layer with the thickness of 5-10 nm. According to the invention, the technical problem of poor crystal quality of an epitaxial layer of subsequent epitaxial growth caused by lattice mismatch generally existing in a light-emitting diode in the prior art can be solved.

The invention discloses a polysilicon ingot furnace with a diversion device. The polysilicon ingot furnace comprises a heat insulation cage, a gas pipe and a diversion device. The diversion device is equipped with multiple diversion airways used for dividing input carrier gas into multiple outgoing carrier gas flows. The carrier gas flows are dispersedly and slantly blown to different areas on the surface of liquid silicon, thus effectively increasing contact area of the carrier gas and the surface of liquid silicon and minimizing heat per unit area by carrier gas flow. Thermal drop of liquid silicon in the area is reduced, degree of supercooling is decreased, and impurity nucleation and impurity formation caused by carrier gas are reduced. The outgoing carrier gas flows produce carrier gas stress to liquid silicon so as to drive liquid silicon to flow and to form a rotary flow field for circumferential flow. The rotary flow field is beneficial to transportation and uniform distribution of impurities in liquid silicon. An observation window at the top of the furnace has a field of view leading to the ingot furnace via the diversion device. Through the observation window, state inside the furnace can be observed, and a crystal measurement rod is inserted into the furnace. An infrared detector can detect the state of silicon materials inside the furnace, and the automatic crystal growth process is smoothly carried out.

The invention discloses a CrAlYO coated cutter and a preparation method thereof. The coated cutter comprises a cutter substrate and a (Cr1-a-bAlaYb)2O3 layer which is deposited on the cutter substrate and is of a corundum structure. The preparation method comprises the following steps: pretreating the cutter substrate; then, selectively depositing a Ti1-xAlxN transition layer of a face-centered cubic structure; and depositing a CrAlYO coating. The coated cutter has high hardness, high abrasion resistance and excellent high-temperature oxidation-resistant property; furthermore, the bonding strength between the coating and the substrate is high; and the preparation method is simple in process and low in production cost.

The invention relates to a preparation method of an anticorrosive layer on the surface of stainless steel, in particular to a preparation method of a carbon nanoribbon anticorrosive layer on the surface of the stainless steel. The preparation method aims to solve the problems of poor corrosion resistance of existing stainless steel materials in the acidic environment of fuel cells and short service life of the stainless steel in high-temperature fuel cells. The preparation method comprises the steps that 1, the stainless steel is placed in a vacuum device of plasma enhanced chemical vapor deposition, vacuumizing is carried out, argon gas is injected, and the surface of the stainless steel is etched under certain pressure, temperature and radio frequency power conditions; 2, after etching,a radio frequency power supply is turned off, argon gas and methane gas are injected, and deposition is carried out under certain pressure, temperature and radio frequency power conditions; and 3, after deposition, the radio frequency power supply and a heating power supply are turned off, the methane gas and the argon gas stop being injected, vacuum cooling is carried out to be in a room temperature, and then the preparation method of the carbon nanoribbon anticorrosive layer on the surface of the stainless steel is completed. The preparation method is used for preparing the carbon nanoribbonanticorrosive layer on the surface of the stainless steel.

The invention discloses a method for heterogeneously growing AlN on a SiC seed crystal via a PVT process. The method comprises the following steps: designing a crucible structure comprising a vapor saturation microcavity, wherein vacuumizing and inflating can be conducted in the microcavity; in an initial growth stage of AlN, inhibiting forward decomposition and sublimation of initial SiC and realizing growth of AlN by adopting the vapor saturation microcavity, inhibiting lateral sublimation of the initial SiC by covering of an adhesive with weak air holes, and allowing an AlN polycrystalline spacer to gradually sublimate from the back and to be deposited on the surface of the SiC; after sublimation of the polycrystalline spacer disappears, transporting Al atoms obtained by sublimation at AlN source powder to a growth surface; and after the AlN polycrystalline spacer and the AlN adhesive sublimate, allowing an AlN layer to cover the SiC seed crystal, and enabling the AlN adhesive on the side surface of the SiC to sublimate to leave a crucible area, thereby realizing lateral sublimation and decomposition of the SiC and gradual disappearing of the SiC seed crystal layer and obtaining the SiC-free AlN seed crystal. By adopting the method disclosed by the invention, the crack-free AlN seed crystal with high single crystal rate and low impurity content can be prepared.