82results about How to "Facilitate subsequent purification" patented technology

The invention relates to a method for extracting high-purity steviol glycosides from stevia rebaudiana. The method comprises the following steps: (1) soaking a ground stevia rebaudiana raw material into water, and adding a cellulase preparation for enzymolysis; (2) carrying out heating extraction and centrifugation, and filtering, so as to obtain stevia rebaudiana enzyme extraction liquid; (3) carrying out water-bath heating on the stevia rebaudiana enzyme extraction liquid, adding an inorganic salt flocculating agent, stirring, flocculating, carrying out centrifugation, and filtering, so as to obtain stevia rebaudiana edulcorated liquid; (4) carrying out decolorization adsorption on the stevia rebaudiana edulcorated liquid by virtue of a macroporous adsorption resin column, carrying out elution through eluent, carrying out nanofiltration, and concentrating, so as to obtain a stevia rebaudiana concentrated liquid; and (5) carrying out silica-gel column chromatography and elution on the stevia rebaudiana concentrated liquid, collecting each fraction, concentrating, and drying, so as to obtain multiple high-purity steviol glycosides products. The purity of the products obtained by virtue of the method can reach up to 98.4%, and the final yield is more than 90%; the residual amounts of ethanol and ethyl ester are low, so that the method is environmentally friendly and safe; the method is simple in process, high in operability, low in energy consumption and cost and applicable to industrial production.

The invention specifically relates to a method for preparing a fluorine-silicon tri-block copolymer through activators regenerated by electron transfer-atom transfer radical polymerization (ARGET ATRP) under the condition of a low catalyst concentration, belonging to the field of technical materials. According to the invention, an excess weak reducing agent is used to continuously reduce a passivating agent in a system, and an activator prepared through in-situ reaction catalyzes atom transfer radical polymerization of a monomer; in such a process, a small amount of oxygen hard to thoroughly remove in the system can be consumed in situ; the amount of a catalyst used in a polymerization system is substantially reduced at the same time; and the step of removal of copper in subsequent operation can be avoided. The preparation method for the fluorine-silicon tri-block copolymer has the advantages of a low catalyst concentration, mild reaction conditions and suitability for industrial production.

The invention relates to the field of environment protection equipment and discloses a gas cleaning tank which comprises a rack, a stirring mechanism and a tank body, wherein a liquid outlet is formedin the bottom of the tank body; the stirring mechanism comprises a stirring shaft, fan blades, an air inlet cylinder and a stepper motor; a piston is arranged inside the air inlet cylinder; an air inlet tube is fixed on the air inlet cylinder; a cavity is formed in the stirring shaft; an air outlet one-way valve and an air inlet one-way valve are fixed on the side wall of the piston or the air inlet cylinder; the stirring shaft penetrates through the tank body, the piston and the air inlet cylinder; the stirring shaft is in threaded connection with the piston; a plurality of beads are arranged between the stirring shaft and the piston; a chute is formed in the side wall of the air inlet cylinder; a sliding block is fixed on the side wall of the piston; a water outlet is formed in the lower end of the stirring shaft; the fan blades are fixed on the stirring shaft; and through holes are formed in the fan blades. By adopting the gas cleaning tank, the sizes of bubbles can be reduced, andthe contact areas of the bubbles with a solution are increased.

The invention discloses an extraction method for grape seed polyphenols, which comprises the following steps: 1) grape seed raw material is dried and then pulverized; 2) the pulverized grape seed raw material is placed in leachate to be subjected to leaching treatment to obtain grape seed raw juice; 3) the grape seed raw juice is filtered to obtain grape seed polyphenols. The extraction method has the benefits as follows: a water-ethanol double aqueous phase system is adopted to replace the traditional leaching method that polyphenols in grape seeds are extracted by a single solvent; as the polarities of leaching solvents can be adjusted better through solvent compounding, not only is the extraction rate of polyphenols in grape seeds increased, but also the selectivity of solvents is improved so as to facilitate follow-up purification, what's more, the solid to liquid ratio of the traditional technology is reduced from 1:20 to 1:1.5 in the whole extraction process, and massive water resource can be saved in the extraction technology.

The invention relates to an artificially synthesized signal peptide and application thereof. An amino acid sequence of the signal peptide is selected from any one of SEQIDNO: 1-5. The signal peptide can be added in a mammal zooblast expression vector for guiding a mammal source protein to secrete and express, and can improve the exogenous protein expression in a zooblast by 2-36 times.

The invention belongs to the field of natural pharmaceutical chemistry and discloses a method for extracting mulberroside A from white mulberry root-bark. The method comprises the following steps of: 1) crushing the white mulberry root-bark, adding an ethanol solution at the concentration of between 30 and 90 percent in an amount which is 6 to 15 times that of the crushed mulberry root-bark, refluxing and extracting for 1 to 3 times, decompressing an extracting solution to recover ethanol, regulating the pH value to 4 to 5, standing and precipitating, and filtering to obtain a concentrated solution; 2) adding the concentrated solution into an ultrafiltration membrane and ultrafiltering, adding permeate into macroporous resin and absorbing, eluting by using an ethanol solution at the concentration of between 40 and 60 percent, collecting eluent, concentrating under reduced pressure, regulating the pH value of a concentrated solution to 4 to 5, filtering, and adding ethyl acetate and extracting to obtain extract liquor; and 3) recovering a reagent from the extract liquor, adding activated carbon and drying, loading into an activated carbon column, performing gradient elution by using ethanol solution, performing thin-layer detection, collecting target ingredients, concentrating, and drying at low temperature to obtain the mulberroside A. The process is easy to operate, is low in production cost and is suitable for industrialized production.

The invention provides a method for preparing a gonadotropin-releasing hormone (GnRH) parallel body and a vaccine in solid-phase conditions. After Lys is coupled on carrier resin, rink amide liners are respectively coupled on the two side chains of the Lys, and two same peptide chains are synthesized simultaneously. Disulfide bond bridging is realized on a solid phase, full-protective oxidation is adopted, and a large amount of impurities caused by the reaction involved by the side chains in the process are avoided.

The invention discloses a sewage treatment device for a municipal pipeline network, which comprises a sedimentation tank, a sludge mixing tank, a purification tank and an air-dissolving tank. The sedimentation tank is connected to the sludge mixing tank through a mud delivery pipe, and a second Stirring chamber and pressurized pipe, the second stirring chamber is provided with a stirring mechanism, the pressurized pipe is provided with a conveying screw, the end of the conveying screw is provided with a third motor, and a filter ball is provided in the sedimentation tank, which is connected by a sewage pump Purification tank, the purification tank is divided into a first mixing chamber and a purification chamber through a partition, a permeable membrane is set on the partition, the first stirring chamber is connected to the sludge mixing tank through a mud guide pipe, and the upper and lower intervals in the purification chamber are provided with drug discharge pipes and The deflector and the purification pool are connected to the dissolved air tank through the dissolved air water pump. The invention has simple structure and strong practicability, can not only improve the sewage purification treatment effect, make sludge and sewage be separated rapidly, but also facilitate the recycling of sludge and sewage, reduce waste of resources and realize recycling.

The invention relates to the technical field of biology and discloses a whole genome cloning method of pelteobagrus fulvidraco bacillus-shaped virus. The method comprises the following steps of: designing 14 specific primers for reverse transcription and 14 pairs of specific primers for PCR, wherein the primer sequences are shown as SEQ ID No.1-SEQ ID No.14; extracting pelteobagrus fulvidraco bacillus-shaped virus RNA; taking the extracted viral RNA as a template, respectively adding the extracted viral RNA into a reverse transcription reaction system and a PCR reaction system by using the primers, cloning the whole genome of the pelteobagrus fulvidraco bacillus-shaped virus by sections under reaction conditions, wherein 13 fragments of the amplified product are 2000bp in size, one fragment is 1000bp in size, a total of 14 fragments contain the entire genome sequence of the pelteobagrus fulvidraco bacillus-shaped virus. The invention provides a cloning method of the whole genome of thepelteobagrus fulvidraco bacillus-shaped virus. The method not only can be used for rapid cloning of the whole genome of the pelteobagrus fulvidraco bacillus-shaped virus, but also can be used for researching molecular biology pathogenic mechanism and molecular epidemiology investigation of the pelteobagrus fulvidraco bacillus-shaped virus, and is convenient to use and has good effect.

The invention belongs to the field of organic synthesis, and particularly relates to a method for synthesizing cyclic carbonate and derivatives thereof, which comprises the following step of: reactingan epoxy compound shown in a formula I with carbon dioxide under the catalysis of a catalyst shown in a formula II to obtain a target product. The product prepared by the method has the advantages ofhigh yield, high purity, low catalyst cost and mild synthesis conditions, and the obtained product has no metal residue.

The invention discloses a production system for preparing formaldehyde, paraformaldehyde, methylal and hexamethylene tetramine from methanol, and belongs to the technical field of compound preparation. A process includes the steps that S1 methanol is used as a raw material and is subjected to recovery to obtain a low-concentration formaldehyde solution through oxidation, and unrecovered formaldehyde mixed gas is absorbed by an absorption tower to obtain a light aldehyde solution; S2 methanol and the low-concentration formaldehyde solution are used as raw materials and sequentially processed bya resin reactor, a reaction tower, a rectification tower and a cooler to obtain methylal; S3 the low-concentration formaldehyde solution in the process S1 is concentrated by secondary evaporation toobtain a high-concentration formaldehyde solution, and the high-concentration formaldehyde solution is vacuum-dried to obtain paraformaldehyde; and S4 liquid ammonia is used as a raw material, after vaporization, the liquid ammonia reacts with the light aldehyde solution in the step S1, and evaporative crystallization, centrifugation and drying are performed to obtain hexamethylene tetramine. Theproduction system can improve the effective utilization of resources such as the raw materials, reduce the discharge of pollutants, reduce environmental pollution, effectively reduce the production cost of enterprises and improve economic benefits.

Methods for the synthesis of 2-thiohistidine or a derivative thereof of the formula (I), or of a physiologically acceptable salt, a tautomer, a stereoisomer or a mixture of stereoisomers in any proportions thereof, from a compound of the formula (II) or a physiologically acceptable salt, a tautomer, a stereoisomer or a mixture of stereoisomers in any proportions thereof, by cleavage reaction in the presence of a thiol at a temperature higher than or equal to 60° C. The invention also relates to compounds of the formula (II) and a method for the synthesis thereof.

The invention provides a foam separation method for concentrating and separating rosmarinic acid in labiatae (preferably perilla leaves). The method comprises the following steps: 1, a perilla leaf extract is prepared; 2, in the first-stage foam separation, a betaine type surfactant is used as an auxiliary agent, rosmarinic acid is effectively collected to a gas-liquid interface, concentration and separation of perilla rosmarinic acid are facilitated, and an obtained concentrated solution can be directly used as a raw material for producing perilla rosmarinic acid powder; and step 3, second-stage foam separation is carried out by taking the first-stage residual liquid as a feed liquid, so that the recovery effect of the rosmarinic acid in the perilla frutescens is further improved. According to the two-stage foam separation, the concentration (enrichment) ratio of the rosmarinic acid can be greatly increased (7.5-14.0), and the recovery rate can be increased (86%-99%). The method has the advantages of greenness in process, no addition of organic reagents, low energy consumption, simplicity in operation and the like, effectively solves the problem of concentration and separation of rosmarinic acid in perilla frutescens, and has good economic and social benefits.

The invention discloses an environmental-protection garbage incineration device. The device comprises a base; a garbage incineration furnace is fixedly arranged at the top of the base through a bracket; a first drawer is arranged at the inner bottom of the garbage incineration furnace; the bottom of the first drawer is opened, and the opened place is fixedly connected with a ventilation net; the left wall of the garbage incineration furnace is fixedly connected with a feed pipe; the feed pipe is positioned above the first drawer, and is inclined to the right lower side; the left end of the feed pipe is fixedly connected with a feed hopper; a shelf is fixedly connected to the top in the garbage incineration furnace; a heating water tank is arranged above the shelf; the right lower angle ofthe heating water tank is connected with a water inlet pipe; the left upper angle of the heating water tank is connected with a hot water pipe; and the hot water pipe and the water inlet pipe both extend outside the garbage incineration furnace. The device heats water through garbage incineration for resource reutilization to achieve energy conservation and environmental protection; and smoke generated in garbage incineration preheats cold water, so that the heating speed of hot water is higher, and the energy utilization rate is further increased.

The invention discloses a sewage purification device. The device comprises a pretreatment component, a sterilization component, a purification component, a water storage tank, a water outlet, a liquidometer and an electric control cabinet. According to the device, through the arrangement of the pretreatment component, sewage enters the device from a raw water inlet pipe, a pretreatment filter screen pretreats impurities in the sewage, the impurities fall into a waste box, thus, the purpose of pretreatment is achieved, subsequent purification of the sewage is benefited, the purification effectof the purification device is improved, and the service life of the purification device is prolonged; a second valve is opened regularly to discharge the impurities in the waste box from a blow-off pipe, and thus normal running of the pretreatment component is guaranteed; and through the arrangement of the sterilization component and the purification component, when a button switch is pressed, a UV lamp performs sterilization on the sewage, then the sewage enters a purification box and is purified after passing through a primary filter screen, an activated carbon filling layer and a nanofiltration membrane layer, thus, the purpose of thoroughly purifying the sewage is achieved, purified water reaches a recycling standard, and waste of water resources is avoided.

The invention provides an expression purification method restriction enzyme SmaI. The method comprises the following steps that recombinant bacteria containing restriction enzyme SmaI expression fragments are constructed, induced culture is conducted, bacterium bodies are fragmented, a product is purified and recycled, and the restriction enzyme SmaI is obtained; and the purifying modes comprise combination of at least two of Ni ion affinity chromatography, anion exchange chromatography or heparin-affinity chromatography. Through combination of multiple purifying modes, the restriction enzymeSmaI with the purity larger than 98% of obtained.

The invention relates to the technical field of biology, in particular to a method for achieving soluble expression of recombinant CXCL9 (C-X-C motif chemokine 9) protein in Escherichia coli by fusionof a solubilizing label and Intern. The target protein is expressed by fusion with the solubilizing label and the Intein with the self-shear function, and soluble protein and shear release of the target protein are realized. Compared with a known method of expression of recombinant CXCL9 protein in Escherichia coli, the method has the advantages that the process of inclusion volume degeneration renaturation can be avoided, introduction of protease is not needed, a target product with the completely naturally sequence can be obtained, and good application prospect for the enlarged-scale industrial production is achieved.

The invention relates to an injection-grade echinacea extractive and an injection thereof. The extractive is prepared according to the following method: 1) crushing echinacea for usage; 2) warmly dipping the crushed echinacea powder with an aqueous solution containing a base to extract for two times, filtering, discarding medicine residues, and merging the filtrate for usage; 3) applying the filtrate obtained in the step 2) to anion resin, washing with water, then eluting with an ethanol solution containing an acid, collecting the eluate, and recovering ethanol in a reduced-pressure manner, and obtaining a concentrate for usage; and 4) performing salting out on the concentrate obtained in the step 3), refrigerating, filtering, discarding filtrate, and washing the precipitate with water, so as to obtain the extractive. The provided injection is high in content of intermediates chicoric acid and caftaric acid, low in cost and good in medicine effect.