84results about How to "For the purpose of purification" patented technology

The invention discloses an industrial preparation method of high-purity sodium pantothenate. The method comprises the following steps: adding calcium pantothenate into purified water and dissolving to obtain calcium pantothenate solutions; adding sodium carbonate solutions into sodium pantothenate solutions, performing reaction, filtering and collecting filter liquid; adding active carbon into the filter liquid to be filtered and then filtered by a film; concentrating the liquid filtered by the film and adding ethanol; adding concentrated liquid into which ethanol is added into acetone; growing grains and drying to obtain sodium pantothenate. According to the industrial preparation method, high-temperature drying by distillation and multi-time repeated concentration are not needed, so that the working hours are shortened, and the side reaction is reduced; a special crystallizing condition is not needed, so that the problems that ethanol crystals are difficult to dissolve, easy in oil outflow and difficult to separate out are solved; because the process is simple, the working hours can be shortened by 1-2 times, and the production cost can be reduced by more than 50 percent. The used solvent is low in cost, the defects of high solubility of sodium pantothenate in ethanol and low yield are overcome, and the quality and the yield of the product are guaranteed; moreover, the purity of the product reaches 99.8 percent, and the yield is increased to 90 percent; therefore, the method is more suitable for industrial production.

The invention relates to an aqueous two-phase separation method for total flavonoids, saponins and polysaccharides in astragalus. The method comprises the following steps of smashing an astragalus medicinal material; adding a solvent and performing solid-liquid extraction; filtering and removing impurities to obtain crude extract of the total flavonoids and the saponins of the astragalus; taking and concentrating the crude extract of the astragalus; adding an aqueous two-phase system formed by absolute ethyl alcohol / dipotassium hydrogen phosphate, adding water to make the total amount of the system be a constant value; mixing uniformly and standing, wherein the aqueous two-phase system is divided into an upper phase and a lower phase; taking an ethanol phase which contains a large amount of total flavonoids and saponins of the astragalus out; and concentrating the ethanol phase under a reduced pressure to obtain the extract of the total flavonoids of the astragalus. The method has the beneficial effects that the extraction rate of the total flavonoids and the total saponins of the astragalus; simultaneously the total flavonoids and the total saponins can be separated from the polysaccharides of the astragalus in the crude extract; the used solvent is low in toxicity, favorable to environment friendliness and low in cost; the inactivation or the denaturation of the flavonoids and the saponins of the astragalus cannot be caused; the phase separation time is short; the interfacial tension is low; and residual organic solvent does not exist.

The invention discloses a spot welding device and method for buzzer production based on positioning and clamping, and relates to the field of spot welding devices for buzzer production based on positioning and clamping, including a spot welding box, and spot welding is arranged above the spot welding box In order to solve the inconvenient fixing phenomenon in the production and processing of the buzzer, first of all, multiple sets of electronic buzzers are spaced into multiple sets of fixing holes on the spot welding table. When the electronic buzzer is located on the spot welding The rubber ring is elastically deformed by pressing the inclined surfaces in multiple sets of fixing holes on the table. The cross-section of the rubber ring forms an L-shaped clamping state covering the outer ring of the electronic buzzer, and the magnetic suction ring is adsorbed and fixed on the electronic buzzer. The bottom forms an adsorption-type positioning state, so that the electronic buzzer is stably clamped and fixed, and the adsorption-type clamping is fixed, and the structure is stable. At the same time, the adsorption-type clamping and fixing can cover and clamp the elastically deformable rubber ring The exterior of the electronic buzzer further increases the stability of the electronic buzzer.