33results about How to "Overcome the disadvantage of uneven heating" patented technology

The invention provides a preparation method of kilogram-grade high-purity silicon carbide powder, and the preparation method comprises the following steps: (1) coating a graphite crucible with a carbon film; (2) coating the graphite crucible coated with the carbon film with silicon carbide, (3) putting mixed silicon powder and carbon powder into the crucible, putting the crucible in a heating pipe, putting the heating pipe into a medium-frequency induction heating furnace, pumping air out of the system, heating, filling high-purity argon, helium or a hydrogen and argon mixed gas, heating to the synthesis temperature, keeping warm for a certain time, and then cooling to obtain the kilogram-grade high-purity silicon carbide powder. The method can effectively remove the majority of impurity elements in the silicon powder and the carbon powder, can eliminate interferences of non intentionally doped impurities on high-purity half-insulating silicon carbide single crystal growth or N-type doping and P-type doping silicon carbide single crystal growth, and is conducive to stabilizing crystal type, resistivity and other electrical parameters.

The invention relates to a multi-morphologic Ho/BiVO4 composite photocatalyst, and a preparation method and an application thereof. The main component of the multi-morphologic Ho/BiVO4 composite photocatalyst is BiVO4, the BiVO4 has a tetragonal zircon phase structure, and the crystal lattice of the BiVO4 contains Ho<3+>. The preparation method comprises the following steps: respectively dissolving bismuth nitrate pentahydrate and ammonium metavanadate in water to obtain a bismuth salt solution and a vanadium salt solution, adding the vanadium salt solution to the bismuth salt solution according to a molar ratio of Bi to V of 1:1 to obtain a mixed solution, adjusting the pH value of the mixed solution to 8, adding holmium nitrate hexahydrate according to a molar ratio of Ho to Bi of (2.04-13.64):100, and maintaining the temperature at 180DEG C unchanged for 40min under a power of 300W by using a microwave hydrothermal method to prepare Ho/BiVO4. The preparation method has the advantages of uniform heating, fast heating speed, mild reaction condition, simple process flow, shortened reaction time and increased work efficiency, and the synthesized multi-morphologic Ho/BiVO4 composite photocatalyst has a high photocatalytic activity and can be used for degrading environmental pollutants.

The invention discloses a preparation method of a rod-shaped self-assembled spherical zinc-cadmium-sulfur solid solution material. The preparation method comprises the following steps: measuring H2O with a measuring cylinder, adding 10mL of EN (ethylene diamine) to prepare a mixed solution, and performing magnetic stirring and ultrasonic treatment to form a mixed solution A; adding zinc acetate dihydrate and cadmium nitrate tetrahydrate which are taken as raw materials into the mixed solution A, and performing magnetic stirring and ultrasonic treatment to form a mixed solution B; adding L-cysteine which is taken as a sulfur source into the mixed solution B, and performing magnetic stirring and ultrasonic treatment to form a mixed solution C; adding the mixed solution C into an inner liningmade of polytetrafluoroethylene, and performing microwave hydrothermal reaction; and after the reaction is completed, performing centrifugal washing respectively with deionized water and ethanol forseveral times, and then performing drying and grinding to obtain zinc-cadmium-sulfur solid solution material powder.

The invention discloses a preparation method and application of a polymeric phosphato aluminum iron chloride coagulant under a micro-wave irradiation condition. The method comprises the steps of: based on aluminum polychloride and FeCl3.6H2O as main materials, adding water to dissolve and evenly mixing; then adding disodium hydrogen phosphate solution to adjust the molar ratio of phosphorus to ferro-aluminum; putting into a microwave reactor to radiate and heat, so as to polymerize under a microwave condition; taking out from the microwave reactor; adding NaOH solution to adjust the alkalization degree and continuing to react for a period of time under the condition of a water bath; and finally curing at normal temperature to obtain polymeric phosphato aluminum iron chloride. The prepared polymeric phosphato aluminum iron chloride coagulant can be widely applied to treatment of source water, and treatment of industrial wastewater and domestic wastewater; and the function is superior to that of common aluminum polychloride and ferric polychloride. The polymeric phosphato aluminum iron chloride disclosed by the invention can effectively reduce the turbidity and UV254 of a water body in feedwater treatment; and the polymeric phosphato aluminum chloride iron disclosed by the invention has good removal effect on the turbidity, chemical oxygen demand (COD) and total phosphorus in domestic wastewater and industrial wastewater.

The invention relates to a Dy/BiVO4 photocatalyst as well as a preparation method and an application thereof. The Dy/BiVO4 photocatalyst comprises a principal component of BiVO4, is in a square zircon-shaped structure and contains Dy<3+> in a BiVO4 lattice. The preparation method comprises the following steps: respectively dissolving bismuth nitrate pentahydrate and ammonium metavanadate in water to obtain a bismuth salt solution and a vanadium salt solution; adding the vanadium salt solution to the bismuth salt solution to obtain a mixed solution according to the mole ratio that Bi to V is equal to 1 to1; regulating the pH value of the mixed solution to 8; then adding dysprosium nitrate hexahydrate, wherein the mole ratio of Dy to Bi is (2.04-13.64) to 100; keeping temperature at the power of 300W and the temperature of 180 DEG C for 40 minutes by adopting a microwave hydrothermal method to prepare Dy/BiVO4. The preparation method disclosed by the invention combines the advantages of microwave heating and hydrothermal methods for synthesizing powder, is high in heating speed, uniform in heating, and capable of shortening the reaction time and improving the working efficiency; the synthesized Dy/BiVO4 photocatalyst is relatively high in photocatalysis activity and can be applied to environmental pollutant treatment.

The invention relates to a SnO2 nanorod for a negative electrode of a lithium ion battery, and a preparation method of the SnO2 nanorod. The preparation method comprises the following steps of: adding SnCl2*2H2O into deionized water to obtain milky solution, and performing ultrasonic treatment after adding super P into the milky solution so as to obtain uniform mixed solution; performing microwave hydrothermal reaction of the mixed solution to obtain a SnO2/super P composite material; and sintering the SnO2/super P composite material so as to obtain the SnO2 nanorod. According to the SnO2 nanorod for the negative electrode of the lithium ion battery, and the preparation method of the SnO2 nanorod disclosed by the invention, the super P is used as a template; the structure of a nano material can be controlled to a certain degree, such that aggregation of the nano material is inhibited; compared with the conventional hydrothermal method, a microwave hydrothermal method has the advantages that: microwave is used as a heating tool; stirring in a molecular level is realized; the non-uniform heating disadvantage of a hydrothermal container is overcome; the reaction time is shortened; the working efficiency is increased; and the nano material having complete crystallization and uniform particle size distribution can be prepared; and furthermore, the method is simple to operate, short in period and low in cost, and is suitable for large-scale production.

The invention discloses a preparation method of infant rice flour with functions of quick solubility and easy digestion. The method comprises the following steps: firstly, grinding and sieving raw material rice, pulping the rice with water, performing dissolving and uniformly mixing to prepare rice milk with the mass percent concentration of rice flour in the mixture being 15-20%, and then passing the rice milk twice through a colloid mill to obtain milled milk; then, adding high-temperature-resistant alpha-amylase and an enzyme activity accelerant into the milled milk, performing enzymolysis for 30-60 minutes at the temperature of 80-90 DEG C, detecting the DE value after enzymolysis, and performing enzyme deactivation to obtain enzymatic hydrolysate; thirdly, performing spray drying on the enzymatic hydrolysate for 5-10 seconds at the air inlet temperature at 170-180DEG C and the air outlet temperature at 90-95DEG C to obtain the product infant rice flour; and finally, detecting the DE value, the water solubility index WSI and the in-vitro digestion performance of the infant rice flour. According to the prepared infant rice flour, the palatability, the brewing performance and the digestion and absorption performance of the infant rice flour can be effectively improved.

The invention relates to the technical field of organic synthesis, in particular to a N-(5-[1,3,4]diazole-2-yl-2H-pyrazole-3-yl)-carboxamide derivative and a microwave hydrothermal synthesis method thereof, and further relates to application of the compound. A series of basic raw materials such as amine, 2,3-dicyan-opropionate, alcohol, acyl halide and the like are used for synthetizing of pyrazolecarbonitrile, pyrazolecarbonitrile is subjected to esterification, hydrazide reaction and amidation and reacts with a cyclization agent by the microwave hydrothermal synthesis method so as to obtainN-(5-[1,3,4]diazole-2-yl-2H-pyrazole-3-yl)-carboxamide derivative (including thiadiazole and oxadiazole). The derivative has good biological activity, can inhibit various bacterial stains, and has high activity in terms of bacterial resistance and insect killing; in terms of chemical structure, the derivative, according with the general formula, is synthetized, has great variety of active groups and excellent photo-physical properties, has multiple functions in the fields such as photoelectricity, medicines, pesticides, bacteriostat, diminish inflammation and virus protection, and accordinglyhas high development and application value.

A method for preparing lanthanum cuprate (La2CuO4) powder by means of the microwave-hydrothermal method includes the following steps: lanthanum nitrate is added into distilled water, so that solution A is obtained; copper nitrate is added into the solution A, so that solution B is obtained; citric acid is added into the solution B, so that solution C is obtained; the pH of the solution C is regulated to 1.5 to 7, so that solution D is obtained; the solution D is added into a microwave-hydrothermal reactor, the reactor is sealed and then put into a microwave-hydrothermal instrument to carry out hydrothermal reaction, and after reaction is finished, the reactor is naturally cooled to the room temperature; sample is collected by centrifugal separation and then repetitively washed by distilled water and acetone, and after drying, the La2CuO4 powder is obtained. Since the method adopts the microwave-hydrothermal method to prepare the La2CuO4 powder, the electric field and the magnetic field can be changed in the space, so that molecular motion can be intensified, as a result, heat energy can be obtained, and thereby the synthesis of the La2CuO4 powder becomes highly efficient, simple and highly repetitive. Moreover, the heating speed is high, heating is uniform and does not have the temperature gradient and the hysteresis effect, consequently, the defect of ununiform heating of a hydrothermal container is overcome, the reaction time is shortened, energy consumption is reduced, and the working efficiency is increased.

The invention discloses a method for preparing silicon sol by using a tubular slurry reactor and provides a reactor for preparing silicon sol, wherein an aim of homogeneous phase of the system is achieved by using the gas (H2) generated by silicon powder hydrolysis under the synergistic effect of the rising effect, the silicon powder settling and the liquid level rising in the tubular reactor. In the invention, with the stirring effect on the system caused by the gas generated by the silicon powder hydrolysis, dynamic balance among the silicon powder settling, alkali liquid rising and gas rising is realized so that the silicon powder is in a suspended state and does not settle to the tube bottom. Meanwhile, the bubbles (H2) generated by the silicon powder hydrolysis are of the same size and are generated in each position in the tube, and the gas distribution is uniform without dead angle. By adopting the tubular slurry reactor, the contact area between the heating medium and the reactants is increased, and the shortcoming of non-uniform heating is overcome.