46results about How to "Don't need protection" patented technology

The invention discloses a preparation method for Er<3+>-Yb<3+>-co-doped NaYF4 fluorescent powder of which the crystalline phase can be controllably synthesized. The method comprises the following steps that yttrium acetate, ytterbium acetate, erbium acetate and sodium hydroxide are batched and mixed, isopropanol, ethyl alcohol and water serve as solvent, trifluoroacetic acid is added, and transparent sol A is obtained after the mixture is stirred evenly; heat treatment is performed on colloidal matter obtained by drying the transparent sol A, the temperature is increased to 300-800 DEG C from the room temperature, heat preservation is performed for a certain time, and the colloidal matter is cooled to the room temperature along with a furnace and then ground to obtain the Er<3+>-Yb<3+>-co-doped up-conversion fluorescent powder with different crystalline phase compositions and multiple light emitting colors. The preparation method is simple in synthesis technology, short in production cycle and capable of easily achieving scale production; the synthesized Er<3+>-Yb<3+>-co-doped up-conversion fluorescent powder is controllable in crystalline phase, diverse in light emitting colors and wide in application.

The invention relates to the technical field of hydroxymethylfurfural preparation, particularly a preparation method of 5-hydroxymethylfurfural, which comprises the following steps: dissolving a saccharide raw material in a dimethylsulfoxide solvent, heating to 80-160 DEG C, adding chromium chloride to react, and detecting the reaction yield of the 5-hydroxymethylfurfural; and when the yield is greater than 90%, quenching the reaction, carrying out vacuum distillation to remove the solvent, diluting the residual liquid with a saturated sodium chloride water solution to obtain a solution to be extracted, extracting with an organic solvent, and drying by distillation to obtain the 5-hydroxymethylfurfural. The mass ratio of the saccharide raw material to the dimethylsulfoxide is 1:(1.5-20), and the addition amount of chromium chloride is 5-20 wt% of the saccharide raw material. The synthetic route is easy and simple to operate, and does not need any inert gas protective atmosphere; the total mass yield is up to higher than 90%, and the purity is up to higher than 96%; and the invention is suitable for industrial production, and enhances the solid content of the reaction to 33%, thereby greatly enhancing the reaction efficiency.

The invention discloses a method for preparing blue titanium dioxide. The method is characterized in that cheap titanium trichloride is used as a raw material, balance conjugate pair titanium tetrachloride is added in a solvent thermal reaction system according to a certain molar ratio, sodium fluoride is used as a stabilizer, and blue titanium dioxide nanometer particles with high stability are synthesized by a one-step method. The method disclosed by the invention is simple, free of insert gas protection and short in period, the obtained product is good in crystallization growth, high in purity, free of agglomeration, high in yield and uniform in grain size, the product is granular, and the size of the product is 15-25 nanometers.

The invention relates to a preparation method of a chlorohydroxyapatite whisker, and belongs to the fields of chemistry and materials. The method comprises the steps: with calcium carbonate and calcium hydrophosphate as calcium and phosphorus source materials and an alkali metal chloride as a fused salt, obtaining the chlorohydroxyapatite whisker material by controlling the composition of the fused salt, the ratio of the fused salt to the calcium and phosphorus mixed material, and the reaction temperature. The diameter of the obtained chlorohydroxyapatite whisker ranges from 0.5 microns to 40 microns, and the length of the chlorohydroxyapatite whisker ranges from 5 microns to 300 microns; the chlorohydroxyapatite whisker is mainly used for reinforcing and toughening ceramics and high molecular biological materials; therefore, the chlorohydroxyapatite whisker has the value of wide application.

The invention discloses a perovskite CsPbBr 3 The method for preparing quantum dots is characterized in that it includes the following features: S1. Prepare a compound containing CsBr, PbBr 2 , a mixed solution of dimethylformamide, oleic acid and oleylamine; S2. In the mixed solution of step S1., add silicon sphere particles, and then stir and react at 30-60°C for at least 1h to obtain the perovskite CsPbBr 3 quantum dots. The preparation method provided by the present invention only needs to add a solid catalyst silicon sphere particle in the preparation process, which can quickly precipitate the perovskite CsPbBr 3 Quantum dots have simple operation steps, short reaction time, mild conditions, no need for protective gas, high repetition rate, and large-scale production; moreover, the product is stable, the original structure of perovskite will not be destroyed, and the obtained product can still Maintain the original high-efficiency fluorescence characteristics.

The invention discloses a synthesis method of a biaryl six-membered ring lactone compound, which uses 2-arylbenzoic acid as a raw material, realizes C-O cyclization by constant current electrolysis in the presence of a supporting electrolyte, and separates and purifies the compound. After that, the biaryl six-membered ring lactone compound is obtained. The synthesis by the electrochemical method of the present invention has the characteristics of high atom economy, green and high efficiency, avoiding the use of metal catalysts and oxidants, simple process and the like, and is suitable for industrial production.