33results about How to "Solve easy hydrolysis" patented technology

The invention discloses a method for extracting persimmon leaf flavone with content of more than or equal to 85 to 98 percent from a persimmon leaf. The method comprises the following steps of: grinding the persimmon leaf; performing microwave extraction for 1 to 5 times by using water in an amount which is 2 to 10 times that of the persimmon leaf, wherein the pH value of the water is 10 to 14, extraction at each time lasts for 10 to 60 minutes and the extraction temperature is between 30 and 60 DEG C; combining extracting solution and adjusting the pH value to be 5 to 7; adding a flocculation clarifying agent; stirring, standing and filtering; performing ultrafiltration membrane purification and reverse osmosis (RO) membrane dehydration on the filtrate; adjusting the pH value of concentrated solution to be 4 to 5; extracting the obtained concentrated solution by using ethyl acetate for 2 to 6 times; concentrating the extraction liquid; and drying to prepare the persimmon leaf flavones. By the method, the process is simple; the production cost is low; the extraction time is short; environmental pollution is small; and the flavonoids content of the extract is high and can reach 85 to 98 percent.

The invention discloses synthesis and application of a solid acid catalyst and particularly relates to a solid acid catalyst for preparation of sodium isophthalate diethylene glycol 5-sulfonate via direct esterification and preparation and application of the solid acid catalyst; the solid acid catalyst comprises an inorganic lamellar structure material and an intercalation element; the inorganic lamellar structure material may be one or any of montmorillonite, mica, purified bentonite, kaolin, graphite, hydrotalcite and a tetravalent metallic insoluble salt; and the intercalation element may be one or any of Ti, O, H and C. The solid acid catalyst has high catalytic activity in the production of sodium isophthalate diethylene glycol 5-sulfonate from 5-sulfoisophthalic acid monosodium salt and diethylene glycol via direct esterification, the catalyst is easy to separate from the product after reaction, and the catalyst is reusable after being activated.

The present invention relates to the field of polyimide, in particular to a preparation method of polyimide resin, comprising the following steps: S1, after dissolving the first batch of polydiamine in a solvent under an inert gas atmosphere, heat the polyimide at 30°C and In the following low temperature environment, add 105‑110% of the first batch of polyvalent diamine molar total polyvalent dianhydride to polymerize first to form a resin solution, and control the viscosity of the resin solution at 50000‑70000cps; Gradually raise the temperature inside, add the second batch of polydiamines in batches, first more and then less gradually, until the viscosity of the resin solution is 180000-200000cps; S3, add fluorine-containing end-capping agent and mix evenly, and obtain polyimide after high-vacuum defoaming Resin solution, the polyimide coating formed has strong thermal stability, and the thermal expansion coefficient is close to that of the base film.

The invention discloses a preparation method of niobium, tungsten and tantalum-doped cobalt trioxide and belongs to the technical field of lithium ion batteries. The preparation method is characterized in that the synthetic reaction is performed by taking a certain concentration of cobalt solution as a cobalt source, a sodium hydroxide solution as a precipitating agent, an ammonia aqueous solutionas a complexing agent, a hydrazine hydrate solution as a reducing agent and a niobium, tungsten and tantalum chloride anhydrous alcohol solution as a doping agent; in the reaction process, the niobium, tungsten and tantalum chloride anhydrous alcohol solution is added in a reaction kettle in a dispersive liquid adding manner to participate in the reaction; after the end of the synthetic reaction,a synthetic product is oxidized into hydroxyl cobalt oxide by utilizing a hydrogen peroxide solution under the condition of a certain pH value, and then a mixture is washed, dried and calcined to obtain a niobium, tungsten and tantalum-doped cobalt trioxide product with uniformly-distributed doped elements; the production efficiency is high. The niobium, tungsten and tantalum-doped cobalt trioxide product prepared by the preparation method disclosed by the invention has a doping amount of 0.5-1 percent, has the uniformly-distributed doped elements, has a laser particle size of 15-20 mum, a tap density of more than or equal to 2.5 g / cm<3> and a specific surface area of 1.0-3.0 m<2> / g and has a massive or nearly-spherical appearance.

The invention discloses fully-degradable polylactic acid fiber melt-blowing nonwoven and a preparation method thereof. The nonwoven is characterized in that polylactic acid slices are spinned at a melting temperature; and fiber filaments stretched by hot air is formed by self-adhesion and hot rolling, wherein, the even fineness of the nonwoven fiber filaments is 0.52-5mu m, the surface density is5-50g / m2, the thickness is 0.1-0.9mm, the ratio of longitudinal strength to transverse strength is 0.9-1.2, and the filtering efficiency to bacteria is above 95%. The filtering efficiency of the melt-blowing nonwoven product of the invention to bacteria reaches up to 95% which is far higher than that of the existing similar products. The invention solves the problem of low and uneven longitudinalstrength and transverse strength of the existing melt-blowing nonwoven. The invention lowers the melt-blowing die head temperature to 180-185 DEG C and brings optimal spinning effect. The technology of the invention is easy to operate and control, has favorable technical stability and can carry out industrial production.