1354 results about "Butanediol" patented technology

The invention belongs to the technical field of polyurethane elastomers, and particularly relates to a high-static-rigidity high-damping low-pressure-change polyurethane elastomer and a preparation method thereof. Comprising a polyol component and an isocyanate component, and the polyol component comprises polyol A, a chain extender, a stabilizer, a hydrolysis-resistant agent and a catalyst; the isocyanate component is prepared from isocyanate, polyhydric alcohol B and branched chain unit alcohol; the polyol A comprises amine ether polyol and polytetrahydrofuran ether polyol; the polyhydric alcohol B comprises bio-based hydrolysis-resistant polyhydric alcohol and polytetrahydrofuran ether polyhydric alcohol; the bio-based hydrolysis-resistant polyol is prepared by carrying out a reaction on sebacic acid, 1, 2-propylene glycol and 1, 4-butanediol; the branched-chain unit alcohol is prepared from tetrahydrofuran and isooctanol through a reaction. By introducing the bio-based hydrolysis-resistant polyhydric alcohol and branched chain monohydric alcohol, the damping effect is remarkably enhanced, and on this basis, through formula adjustment and raw material screening, the product toughness is greatly improved, the compression set is reduced, and the performance of the product in heavy haul railway application is effectively optimized.

The utility model provides an emission reduction system for producing tetrahydrofuran from 1, 4-butanediol, and relates to the technical field of chemical production equipment. By arranging the 1, 4-butanediol raffinate separation unit, the 1, 4-butanediol raffinate generated in the tetrahydrofuran production unit can directly enter the film evaporator to be separated, the light component 1, 4-butanediol is rapidly evaporated and flows out from the first gas phase outlet, and the light component 1, 4-butanediol is condensed by the gas phase condenser and then returns to the tetrahydrofuran production unit to serve as a raw material to be recycled. And heavy components of tar in the film evaporator flow out from a first liquid phase outlet at the bottom and are discharged and incinerated. The system can further separate the 1, 4-butanediol raffinate generated in the tetrahydrofuran production unit, and recycle the 1, 4-butanediol in the raffinate, so that the material waste of the 1, 4-butanediol is reduced, and the utilization rate of the 1, 4-butanediol raw material is improved. And meanwhile, the 1, 4-butanediol residual liquid discharge incineration treatment amount is greatly reduced, energy conservation and emission reduction are achieved, and the production cost is reduced.

The invention discloses an anti-hair loss shampoo capable of effectively inhibiting bacteria and controlling oil and a preparation method of the anti-hair loss shampoo, and belongs to the technical field of anti-hair loss shampoo. The anti-hair loss shampoo is prepared from the following components in percentage by weight: 0.2 to 0.5 percent of plant extract nano-liposome, 0.5 to 1.5 percent of surfactant, 0.5 to 1 percent of nitrilotriacetic acid, 0.2 to 0.8 percent of EDTA (Ethylene Diamine Tetraacetic Acid) disodium, 0.1 to 0.5 percent of D-panthenol, 0.5 to 1 percent of piroctone olamine salt, 1 to 5 percent of glycerol, 1 to 5 percent of 1, 3-butanediol, 0.4 to 0.8 percent of hyaluronic acid, 0.2 to 0.5 percent of preservative, 0.2 to 0.5 percent of essence, 0.5 to 1 percent of thickening agent and the balance of deionized water. 0.1-0.3% of tocopherol and the balance of water. According to the invention, a plurality of natural plant extracts with bacteriostatic, oil-control and anti-hair-loss effects are screened and are wrapped by using a nano-liposome technology, and other functional components are reasonably matched, so that the preparation of the efficient, stable and mild anti-hair-loss shampoo capable of effectively inhibiting bacteria and controlling oil is realized, the scalp environment is improved from multiple aspects, and the anti-hair-loss effect is improved. The hair loss problem is effectively reduced, and the requirements of people on anti-hair loss hair washing products are met.

The invention relates to the field of fermentation processes, in particular to a method for preparing 1, 4-butanediol through multi-strain synergistic fermentation, which comprises the following steps: inoculating a first strain and a second strain into a culture medium containing glucose and / or xylose for synergistic fermentation, producing ornithine by the first strain by taking glucose and / or xylose as a substrate, and converting ornithine into 1, 4-butanediol by the second strain. The invention discloses 1, 4-butanediol. Glucose is converted into ornithine through the first strain, ornithine is converted into 1, 4-butanediol through the second strain, the first strain and the second strain are subjected to synergistic fermentation, preparation of 1, 4-butanediol through microbial synergistic fermentation is achieved, and higher metabolic capacity and higher production efficiency are achieved. The mixed sugar of xylose and glucose prepared from biomass raw materials is used as a substrate for fermentation, so that the method has the advantages that the raw materials are easy to obtain, renewable and low in cost, and the production cost can be reduced.

The invention provides a bio-based 1, 4-butanediol composition and a preparation method thereof, and polyester prepared from the bio-based 1, 4-butanediol composition, the bio-based 1, 4-butanediol composition comprises bio-based 1, 4-butanediol, an acidic compound, a nitrogen-containing compound and acetal; the content of acetal in the bio-based 1, 4-butanediol composition is less than or equal to 195ppm. According to the invention, polyester prepared by taking the bio-based 1, 4-butanediol composition as a raw material has a low color value and a low melt index.

The invention discloses collagen polypeptide firming and anti-wrinkle freeze-dried powder, and relates to the technical field of cosmetics. The invention relates to a biological preservative which is prepared from water, butanediol, a bacillus / soybean fermentation product extract, soluble collagen, acetyl hexapeptide-8, panthenol, 1, 2, 4-trimethyl-1, 3-pentanediol and a proper amount of water. The cosmetic is prepared from 1, 2-hexanediol, tetrahydromethylpyrimidine carboxylic acid, hydroxypropyl tetrahydropyrantriol, tremella polysaccharide, saccharide isomeride, a bifidus yeast fermentation product lysate, sodium hyaluronate, DNA sodium, a radix gentianae extract, mannitol, palmitoyl tripeptide-1, palmitoyl tetrapeptide-7, oligopeptide-1, decapeptide-4, oligopeptide-3, hydrolyzed royal jelly protein, folic acid and disodium hydrogen phosphate. The additive is composed of sodium dihydrogen phosphate, citric acid and sodium citrate. The mask can provide rich nutrients for skin, deeply care the skin, moisturize and relieve the skin, tighten the skin, resist wrinkles and make the skin moisturized, glossy, elastic and tight, and is high in use safety and wide in application prospect.

The invention discloses a polyurethane protective adhesive tape for aviation and a preparation method thereof, and relates to the technical field of adhesives. When the polyurethane protective adhesive tape for aviation is prepared, polyester glycol, an ultraviolet absorption monomer, 3-(4-pyridyl) pentane-1, 5-diol, 1, 4-butanediol and isophorone diisocyanate are polymerized to prepare polyurethane; the preparation method comprises the following steps: carrying out a reaction on polyurethane and 2-bromoethyl acrylate to prepare modified polyurethane; enabling the pretreated magnesium hydroxide to react with 3-epoxypropoxy-1, 1, 3, 3-tetramethyldisiloxane and ammonia water in sequence, so as to obtain modified magnesium hydroxide; the modified polyurethane and the modified magnesium hydroxide are mixed and then subjected to compression molding to prepare a polyurethane film; and coating a polyurethane film with the polyacrylate glue solution, and drying to obtain the polyurethane protective adhesive tape for aviation. The polyurethane protective adhesive tape for aviation prepared by the invention has excellent flame-retardant, anti-aging, antibacterial and self-repairing properties.

The invention discloses a method for increasing the content of pyrazines and 2, 3-butanediol substances through high-temperature Daqu micro-ecological regulation and control, and belongs to the technical field of microbial food processing. The invention discloses a method for improving the content of pyrazines and 2, 3-butanediol substances through micro-ecological regulation and control of high-temperature yeast for making hard liquor, and the method comprises the following steps of: combining and inoculating strains, namely bacillus subtilis CGMCC (China General Microbiological Culture Collection Center) 10830, bacillus velezensis CGMCC 7044 and bacillus licheniformis CGMCC 20675, into wheat flour according to a proportion to prepare the high-temperature yeast for making hard liquor. According to the invention, not only are the contents of pyrazine substances and 2, 3-butanediol increased, but also the abundance of beneficial microorganisms such as bacillus, thermophilic fungi and the like is remarkably improved, and a good saccharification fermentation agent is provided for brewing high-quality white spirit.

The invention relates to the technical field of polyurethane adhesives, and provides a heat-conducting polyurethane structural adhesive and a preparation and use method thereof.The heat-conducting polyurethane structural adhesive comprises a first component and a second component, and the first component comprises modified bio-based polyol, polythiol, heat-conducting filler, a first water removal agent, a thixotropic agent, a first catalyst and a second catalyst; the second component comprises epoxy resin, diisocyanate, polyisocyanate, a heat-conducting filler, a coupling agent, a second dewatering agent, a dispersing agent and a retarder; the modified bio-based polyol is selected from at least one of modified castor oil polyol, modified grease polyol and modified cashew nut shell oil polyol; the polythiol is selected from at least one of trimethylolpropane tri (3-mercaptopropionic acid ester), pentaerythritol tetra (3-mercaptopropionic acid ester), butanediol mercaptopropionic acid ester and polythiol. Through the arrangement, the heat-conducting polyurethane structural adhesive has relatively long openable time, and is rapidly cured at room temperature within a short time to generate relatively high initial curing strength.

The invention relates to the technical field of flame-retardant materials, and particularly discloses a graphene-modified flame-retardant polyurethane material and a preparation method thereof.The graphene-modified flame-retardant polyurethane material is prepared from, by weight, 60-70 parts of polyhydric alcohols, 30-40 parts of isophorone diisocyanate, 0.4-0.8 part of dibutyltin dilaurate, 3-6 parts of dimethylolpropionic acid, 15-20 parts of composite flame retardant, 2-4 parts of 1, 3-butanediol, 2-4 parts of 1, 3-butanediol, 2-4 parts of 1, 3-butanediol, 2-4 parts of 1, 3-butanediol, 2-4 parts of 1, 3-butanediol, 2 and 1 to 3 parts of 1, 4-butanediol and 1 to 3 parts of perfluorooctyltriethoxysilane. The preparation method comprises the following steps: 1) preparing castor oil-based polyester polyol through hydroxylation reaction and polycondensation; 2) taking graphene oxide as a core, grafting phosphorus and nitrogen flame-retardant groups and carrying out silane-titanate synergistic modification to prepare a composite flame retardant; 3, polyhydric alcohol and isocyanate are pre-polymerized, then the chain extender, the composite flame retardant and the auxiliaries are sequentially added, and curing molding.The material has low smoke and excellent flame retardance, mechanical property and hydrophobic stability through the synergistic effect of graphene and a phosphorus-nitrogen flame-retardant system, and is suitable for the field of flame-retardant high polymer materials for buildings, electronic packaging and the like.

This invention discloses a visible-light-responsive dynamically covalently cross-linked self-healing polyurethane and its preparation method, belonging to the field of self-healing materials technology. The material is prepared by reacting diisocyanate, long-chain diol, butanediol, trimethylolpropane, and a monool containing an azophenylboronic acid structure in a certain proportion at 60°C. This invention achieves visible-light-responsive self-healing of the polyurethane material by introducing a visible-light-responsive azophenylboronic acid structure into the polyurethane and utilizing the photoresponsive cis-trans isomerization of the azo structure to regulate the reversible breakage and recombination of the boron-oxygen hexacyclic ring. The visible-light-responsive dynamically covalently cross-linked self-healing polyurethane material prepared by this invention maintains high mechanical strength (16.47 MPa) while exhibiting a strength self-healing efficiency of 95.8% after 8 hours of visible light irradiation, showing broad application prospects in smart materials, anti-corrosion coatings, and other fields.

The invention discloses a medical sodium hyaluronate skin repair gel and a preparation method thereof, and mainly relates to the technical field of hyaluronic acid, the medical sodium hyaluronate skin repair gel comprises the following components: sodium hyaluronate, a synergist, glycerol, carbomer, 1, 3-butanediol, triethanolamine and water. Compared with the prior art, the medical sodium hyaluronate skin repair gel prepared by the invention can relieve erythema, pruritus and other symptoms caused by skin inflammation; the wound dressing can also be used for nursing non-chronic wounds, such as superficial wounds, sutured wounds after operations, mechanical wounds and the like; meanwhile, a bacteriostatic environment for wound healing is kept, and skin repair is accelerated; the scar hyperplasia phenomenon in the skin wound repairing process is reduced.

The invention discloses a catalyst for preparing gamma-butyrolactone through liquid phase dehydrogenation of 1, 4-butanediol as well as a preparation method and application of the catalyst. Belongs to the technical field of catalyst preparation. The catalyst is composed of a carrier, CuO and MOx, the CuO and the MOx are loaded on the carrier, Cu accounts for 10-50% of the total mass of the catalyst, M accounts for 1-25% of the total mass of the catalyst, M is one of Mn, Zn, Co, Ni, Fe, Cr, Ce, Nb, Ru, Pt, Ir and Pd, and the carrier is one of silicon oxide, aluminum oxide, magnesium oxide, lanthanum oxide, hydroxyapatite and magnesium-aluminum hydrotalcite. An oxide-oxide interface is formed between CuO and MOx through roasting and reduction, and relatively strong electron interaction exists between highly dispersed Cu nanoparticles and the oxide-oxide interface, so that the stability of the catalyst can be enhanced.

The invention provides a clostridium endophyllum engineering bacterium as well as a construction method and application thereof, and belongs to the technical field of biology, compared with a wild type strain, the clostridium endophyllum engineering bacterium can only produce acetic acid in a low-pH environment under the condition of taking CO2 and H2 as raw materials, and does not generate by-products such as ethanol, lactic acid, 2, 3-butanediol and the like. Besides, the fermentation liquor of the clostridium endophyllum engineering bacteria can be directly used as an acidic substrate to adjust the pH value of downstream yeast fermentation liquor, meanwhile, automatic addition of a carbon source is achieved, zero addition of inorganic salt in the cascade conversion process from CO2 and H2 to grease or yeast protein is achieved, and the economical efficiency and environmental friendliness of the whole process are improved.

The invention provides a bio-based 1, 4-butanediol composition as well as a preparation method and application thereof, and the bio-based 1, 4-butanediol composition comprises bio-based 1, 4-butanediol, 4-hydroxybutyric acid-(4-hydroxyl) butyl ester and bis (4-hydroxyl) dibutyl ether. The total mass content of 4-hydroxybutyric acid-(4-hydroxyl) butyl ester and bis (4-hydroxyl) dibutyl ether in the bio-based 1, 4-butanediol composition is 51 to 220 ppm. The bio-based 1, 4-butanediol composition has low hygroscopicity, and can maintain low water content after long-term storage; meanwhile, when the bio-based 1, 4-butanediol composition is used for polyester synthesis, the esterification time can be shortened, the reaction efficiency can be improved, side reactions can be reduced, and a polyester product with better damp-heat resistance stability can be obtained.

The invention relates to the technical field of adhesives, in particular to a bio-based polyurethane hot melt adhesive and a preparation process thereof. The bio-based polyurethane hot melt adhesive is prepared from the following raw materials in parts by weight: 30 to 40 parts of bio-based polyester glycol, 60 to 80 parts of bio-based polyether polyol, 25 to 35 parts of acrylic resin, 40 to 60 parts of isophorone diisocyanate, 3 to 5 parts of bisphenol A epoxy resin E-44, 3 to 5 parts of 1, 3-butanediol, 1, 3-butanediol and 1, 3-butanediol. The coating is prepared from the following raw materials in parts by weight: 1-2 parts of 1, 4-butanediol, 0.2-0.6 part of dibutyltin dilaurate, 0.6-1.0 part of 3-aminopropyltriethoxysilane, 3-5 parts of modified carbon nanotubes, 2-4 parts of a curing agent, 1-1.5 parts of an ultraviolet absorbent and 0.8-1.2 parts of an antioxidant. The bio-based polyurethane hot melt adhesive prepared by the invention not only has better adhesive property, but also has excellent mechanical property and aging resistance, and the quality of the bio-based polyurethane hot melt adhesive is ensured while the service life of the bio-based polyurethane hot melt adhesive is effectively prolonged.

The invention discloses a recombinant halomonas for producing polyhydroxyalkanoate as well as a construction method and application of the recombinant halomonas. The recombinant halomonas comprises an exogenous gene, the exogenous gene comprises a combination of an aldD gene, a dhaT gene and an orfz gene, and the recombinant halomonas weakens the expression of an endogenous prpc gene. According to the invention, a P34HB synthesis route is successfully constructed through a synthesis route of exogenous introduction from 1, 4-butanediol (BDO) to 4-hydroxybutyryl coenzyme A, the proportion of each monomer in the copolymer can be effectively regulated and controlled, especially after exogenous addition of short-chain fatty acids (such as formic acid, acetic acid, propionic acid, butyric acid and the like), the synthesis of copolymers such as PHB, PHBV, P34HB, P34HB3HV and the like can be further improved, and the synthesis efficiency of the copolymer is improved. And the proportion of different monomers is adjusted, so that the diversity and yield of the copolymer are enhanced.

The invention discloses a full bio-based copolymer based on a citric acid bicyclic monomer, a preparation method and an application, and belongs to the technical field of material synthesis, citric acid-derived bicyclic OPD diol and OPBMC diester are synthesized through oxidation reduction and transesterification, and then 1, 4-butanediol is partially replaced with OPD or 2, 4-butanediol is partially replaced with OPBMC through melt phase polycondensation reaction. Two series of random copolyester PBxOyF copolymer and PBOmFn copolymer of the PBF are prepared by adding 2, 5-dimethyl furandicarboxylate into the PBF, and then adding the PBxOyF copolymer and the PBOmFn copolymer into the PBF. According to the full-bio-based copolymer based on the citric acid bicyclic monomer, the preparation method and the application, the citric acid bicyclic monomer obviously improves the glass transition temperature and shows good mechanical properties; therefore, the bicyclic monomer based on citric acid has huge potential in the aspect of synthesizing novel bio-based copolyester with expected thermodynamic properties, and is expected to further expand the application range of the 2.5 furandicarboxylic acid-based polyester.

The invention relates to the technical field of preparation of water-based functional polymer materials, in particular to a preparation method of water-based polyurethane slurry for sports shoe leather, which comprises the following steps: mixing polycarbonate diol, core-shell structure graphene oxide-polycaprolactone hybrid nanoparticles and dimethylolpropionic acid, and carrying out vacuum dehydration treatment, isophorone diisocyanate is added for a reaction, and a polyurethane prepolymer is obtained; after the polyurethane prepolymer is cooled, triethylamine is added for a neutralization reaction; under violent stirring, adding a mixture composed of 1, 4-butanediol and a hyperbranched organosilicon amino chain extender serving as a flexible functional core into the neutralized prepolymer to carry out chain extension reaction, and adding deionized water to carry out reversed-phase emulsification, so as to obtain a waterborne polyurethane emulsion; standing and curing the waterborne polyurethane emulsion at a preset temperature to obtain waterborne polyurethane slurry; the finally prepared shoe leather material has excellent wear resistance and excellent low-temperature bending durability.

The invention relates to the technical field of road crack repairing materials, in particular to a high-strength polyurethane-based road crack repairing material and a preparation method thereof. The composite material is prepared from the following components in parts by weight: 5 to 10 parts of 1, 4-butanediol, 3 to 8 parts of modified nano silicon dioxide, 10 to 20 parts of superfine calcium carbonate, 8 to 12 parts of chopped basalt fiber, 0.5 to 2 parts of 2-(2H-benzotriazole-2-yl)-4, 6-di-tert-pentylphenol, 0.3 to 1.5 parts of carbodiimide and 0.3 to 0.8 part of organic tin-amine composite catalyst. The mechanical strength and the temperature resistance of the material are remarkably improved through a rigid annular structure of dicyclohexylmethane diisocyanate, the material is endowed with elasticity and deformation resistance through a flexible chain segment of polyester polyol, and a repairing layer can bear load impact and can adapt to crack expansion deformation through the synergistic effect of dicyclohexylmethane diisocyanate and polyester polyol; the composite action of the fibers and the filler can disperse stress concentration, reduce the risk of secondary cracking caused by temperature shrinkage or load, and realize long-term stability of crack repair.

The present invention discloses an infrared-shielding polyurethane glass film and a preparation method thereof, relating to the field of polymer materials technology. When preparing the infrared-shielding polyurethane glass film, the present invention comprises reacting an organic nickel complex and 3-imidazole-1-propionic acid to produce a functionalized crosslinker; sequentially reacting 4-aminophenylacetonitrile with 3-hydroxypropyl acrylate and quinoline-4-carboxaldehyde to produce a UV-absorbing monomer; reacting polypropylene glycol, a UV-absorbing monomer, 1,4-butanediol, and 4-chloromethyl-1,3-phenylenediisocyanate to polymerize to produce polyurethane; reacting tungsten-doped titanium dioxide and chloropropyltriethoxysilane to produce modified titanium dioxide; and uniformly mixing the polyurethane, modified titanium dioxide, the functionalized crosslinker, and acetone, followed by coating and curing to produce the infrared-shielding polyurethane glass film. The infrared-shielding polyurethane glass film prepared by the present invention has excellent infrared shielding, anti-aging, antibacterial, and mechanical properties.

The invention provides a catalyst for preparing 1, 4-butanediol through hydrogenation of succinate and a preparation method and application of the catalyst, the structural formula of the catalyst is aAbBcCdD / (xZ1 + yZ2), a component A is selected from at least one of Ru, Os, Rh, Ir, Pd or Pt, a component B is selected from at least one of Cr, Mn, Fe, Co, Ni or Cu, a component C is an oxide of at least one metal of Ga, In, Ge, Sn, Pb, Sb, Bi, Se, Te, Nb, Mo, W, Re, Al, Ti, Zr or Zn, a component D is an oxide of at least one metal of alkaline earth or rare earth, and a component E is an oxide of at least one metal of alkaline earth or rare earth. Z1 is a carrier with high specific surface area, and Z2 is a carrier with high thermal conductivity; the mass percentage content of each component is as follows: a is 0.1 to 10 weight percent, b is 0 to 60 weight percent, c is 0 to 50 weight percent, d is 0 to 20 weight percent, x is 10 to 90 weight percent, and y is 0 to 40 weight percent; or a is equal to 0, b is equal to 15-70 wt%, c is equal to 0-80 wt%, d is equal to 0-15 wt%, x is equal to 0-45 wt%, y is equal to 0-20 wt%, and c and d are not equal to 0 at the same time. The catalyst has excellent catalytic performance on preparation of 1, 4-butanediol by hydrogenation of mono, di or polyester of succinic acid esters including monohydric, dihydric or polyhydric alcohols.

A magnetic nanoparticle composite microcapsule, and a preparation method therefor and the use thereof. The preparation method comprises: diluting concentrated ammonia water with absolute ethanol in which nano-Fe3O4 is dispersed, stirring same and adding ethyl orthosilicate, centrifuging same, and then performing washing to obtain Fe3O4 / SiO2 particles; dispersing same in anhydrous ethanol, then adding isopropanol containing tetrabutyl titanate, and performing a treatment to obtain Fe3O4 / SiO2 / TiO2 nanoparticles; adding polyurethane TDI prepolymer to the Fe3O4 / SiO2 / TiO2 nanoparticles, adding same to a core material, then dripping an emulsifier, and stirring same to obtain a core material emulsion; and heating same in a water bath, dropwise adding butanediol, and performing heating, stirring and vacuum filtration to obtain a magnetic nanoparticle composite microcapsule. By means of the loading with a core material having a repair function, the prepared magnetic microcapsule can actively repair damage to an insulating material caused by electrical and mechanical stress, thereby improving the reliability of a device.

The invention belongs to the technical field of copolymerization modification of degradable polyester, and relates to a depolymerization method and application of polybutylene terephthalate. During depolymerization, polybutylene terephthalate, dimethyl carbonate and dihydric alcohol are mixed and then subjected to a depolymerization reaction, and an intermediate ester is prepared; the dihydric alcohol is dihydric alcohol which does not form a ring with dimethyl carbonate in the depolymerization reaction process; the molar weight of the dimethyl carbonate is 10-30% of the molar weight of a repetitive unit of the polybutylene terephthalate; the sum of the molar weight of a 1, 4-butanediol unit in the polybutylene terephthalate and the molar weight of the added dihydric alcohol is a, the sum of the molar weight of a terephthalic acid unit in the polybutylene terephthalate and the molar weight of the added dimethyl carbonate is b, and the ratio of b to a is (1.2-1.5): 1; during application, the prepared intermediate ester is subjected to transesterification under the condition of negative pressure to obtain the copolyester. The depolymerization method is simple and easy to implement; the depolymerization product can be directly applied.

The invention belongs to the technical field of tetrahydrofuran preparation, and particularly relates to a preparation process of tetrahydrofuran. The preparation process comprises the following steps: 1, introducing 1, 4-butanediol into a catalytic reaction area of a reactor, and carrying out a dehydration cyclization reaction to obtain a gas-phase product and a liquid-phase product; and 2, discharging the liquid-phase product out of the reactor along an annular region between the catalytic reaction region and the inner wall of the reactor. And 3, sequentially carrying out rectification treatment and condensation treatment on the gas-phase product, and separating out tetrahydrofuran and a circular reaction liquid. And 4, mixing the circular reaction liquid with 1, 4-butanediol, and repeating the step 1. Therefore, by removing the liquid-phase product and discharging the gas-phase product in time, the reaction can be promoted to proceed forwards, and the reaction conversion rate can be increased; the recycling of the circular reaction liquid avoids the waste of resources, and greatly reduces the energy consumption and the raw material input, so that the reaction conversion rate can be improved while the production cost is reduced.

The invention belongs to the technical field of microbial fermentation, and particularly relates to a new enterobacter rorrhizae strain as well as a separation and screening method and application thereof. In order to enrich microbial resources for producing pyrazine substances through metabolism in the white spirit industry, an enterobacter rorrhizae strain is separated and screened from a mixture of yeast for making hard liquor and fermented grains, and the preservation number is CGMCC No.33262. The strain has good tolerance to pH, salt and alcohol, and can adapt to the growth environment in the white spirit production process; and various pyrazine substances represented by tetramethylpyrazine can be produced. Besides, the strain has strong adaptability to fermented grains, the yield of tetramethylpyrazine is high in a culture medium taking bran, wheat and five grains as the fermented grains, and meanwhile, various flavor substances such as ethyl acetate, ethyl hexanoate, ethyl caprylate, 2, 3-butanediol, guaiacol and 4-vinyl guaiacol can be produced. Therefore, the enterobacter rorrhizae disclosed by the invention can be widely used for brewing white spirit.

The invention belongs to the technical field of corrugated paperboards, and is characterized in that wood fibers and modified bamboo fibers prepared by reaction of allyl bamboo fibers, 1, 4-butanediol di (mercaptoacetate) and magnolol are pulped, a biodegradable water-resistant auxiliary agent is added for hydrophobic modification, papermaking and shaping are carried out to prepare water-resistant base paper, and the water-resistant base paper is prepared by the following steps: pulping the modified bamboo fibers and the biodegradable water-resistant auxiliary agent. And finally, preparing a surface paper layer, a corrugated medium paper layer and an inner paper layer from the water-resistant raw paper, and bonding and pressing to obtain the corrugated board. Magnolol groups grafted on the surfaces of the modified bamboo fibers can improve the water absorption performance of the fibers, and the hydrophobicity of the corrugated board is improved through the synergistic effect of the magnolol groups and the biodegradable water-resistant auxiliaries; the surface of the biodegradable water-resistant auxiliary agent is embedded with a carboxylated nano-cellulose structure, so that the biodegradable water-resistant auxiliary agent has deformation resistance; the epoxidized soybean oil is used as a core part and has excellent hydrophobicity; through combination of a polyphenol structure of tannic acid and hydrogen bonds of water-resistant base paper fibers, the mechanical properties of the corrugated board are improved, and the corrugated board has excellent biodegradability, hydrophobicity and mechanical strength.

The present invention belongs to the technical field of biochemistry, and provides a method for increasing the yield of 1,3-butanediol synthesized by biological methods. By using the oxygen depletion-induced promoter pfnF8 endogenous to Escherichia coli to drive the expression of key genes in the 1,3-butanediol synthesis pathway, the expression of genes in the 1,3-butanediol synthesis pathway can be automatically induced through the growth of cells and the change of oxygen content during the fermentation process, so as to balance the growth of cells and the synthesis of 1,3-butanediol; at the same time, this method does not require the addition of exogenous inducers, thus saving production costs and being suitable for large-scale industrial production.

The invention discloses a method for improving the performance of clostridium aerovorans for synthesizing ethanol by utilizing gas fermentation. The method comprises the following steps: enabling the clostridium aerovorans to over-express ethanol synthesis pathway genes ald, adhE1 and adhE2; the expression of genes CLJU23220, CLJU25810 and CLJU25840 in the synthetic route of the 2, 3-butanediol is inhibited; and overexpressing acetic acid reuse genes aor1 and aor2. According to the clostridium yangdall engineering bacteria constructed by the method, the yield of ethanol synthesized by fermentation of synthesis gas is increased by 700% or above and reaches 1.70 g / L or above, and the synthesis amount of a by-product acetic acid is reduced by 18%.

The invention relates to the technical field of skin care products, and discloses an anti-aging and whitening composition and a preparation method thereof.The anti-aging and whitening composition comprises anti-aging and whitening components, whitening synergistic components, moisturizing and repairing components and deionized water, and the anti-aging and whitening components comprise botryine, ergothioneine and Ectoine; wherein the mass ratio of the glassine to the ergothioneine to the ectoine is (1.2 to 2.0) to (0.4 to 0.7) to (1.0 to 1.5); the whitening synergistic component comprises one or more of nicotinamide, glabridin and tranexamic acid; the moisturizing and repairing component is prepared from one or more of sodium hyaluronate, ceramide NP, glycerol and 1, 3-butanediol. Experiments show that the mass ratio of the glassine to the ergothioneine to the ectoine is (1.2-2.0): (0.4-0.7): (1.0-1.5), so that the glassine, the ergothioneine and the ectoine show a remarkable synergistic effect (in some cases, the synergistic index CIlt is 0.85), and the anti-aging and whitening functions of the composition containing the glassine, the ergothioneine and the ectoine are improved.