869 results about "Modified starch" patented technology

The invention discloses a pure bio-based PHA aqueous dispersion as well as a preparation method and application thereof, and belongs to the technical field of pure bio-based polymer aqueous dispersion. According to the dispersion, polyhydroxyalkanoate is used as a unique film forming matter, Pickering solid particles and a natural surfactant are adopted for synergistic stabilization, and a bio-based plasticizer can be selected. The emulsion or slurry with the polyhydroxyalkanoate content of 40-85wt% and the particle size of 0.2-3m is prepared through a melting high-pressure homogenization method, a low-temperature wet grinding method or a solvent replacement method. The coating does not contain petrochemical polymer protective colloid and perfluorinated and polyfluoroalkyl substances, and the bio-based content is greater than or equal to 99%. Due to the excellent stability, rheological property and film-forming property of the modified starch, the modified starch becomes an ideal basic material for constructing a multi-layer programmable controlled release and degradation functional coating system, can be used in the fields of paper-based barrier coatings, adhesives, advanced crop seed coats and the like, realizes excellent barrier, bonding and controlled release properties, meets the industrial compost and repulping property standards, and has wide application prospects. The method has green, environment-friendly and industrial potential.

The invention discloses a large-size green packaging carton and a preparation process thereof, and relates to the field of packaging box preparation. The environment-friendly composite material comprises the following raw materials in parts by weight: 50-80 parts of plant fiber slurry, 10-25 parts of a modified starch-based adhesive, 5-15 parts of a nanoscale inorganic reinforcing filler, 1-5 parts of a degradable water repellent agent, 0.5-3 parts of a cross-linking agent and 2-8 parts of starch and plant fiber composite buffer microspheres. According to the preparation method, full-environment-friendly raw materials such as plant fiber slurry and a modified starch-based adhesive are selected and matched with starch and plant fiber composite buffer microspheres, and optimized processes such as segmented temperature control pressurization molding, adhesive gelatinization treatment, stirring speed reduction and microsphere structure protection are combined; and through coating of the degradable polymer coating and micron-sized hydrophobic texture imprinting, synergistic improvement of high compressive strength, excellent buffering performance, excellent hydrophobic and damp-proof effects and high degradation rate of the carton is achieved.

The invention relates to a whitening and freckle-removing composition containing a composite plant extract and a preparation method of the whitening and freckle-removing composition, and belongs to the technical field of cosmetics. The composition disclosed by the invention is prepared from the following raw materials in parts by weight: 5 to 8 parts of pineapple leaf nano cellulose, 10 to 16 parts of modified starch, 10 to 15 parts of longan seed extract, 6 to 10 parts of mulberry bark extract, 5 to 8 parts of nicotinamide and 8 to 10 parts of hyaluronic acid. The pineapple leaf nanocellulose contains flavonoid and phenolic compounds with double-bond, conjugated double-bond and triple-bond structures, and modified starch is used as a filler to form a film on the surface of skin, so that an anti-ultraviolet protection wall is formed; the betaine-malate ionic liquid is added into the longan seeds, so that extraction of polyphenol in the longan seeds is improved, the longan seeds have acid-base buffering capacity, an auxiliary does not need to be added to adjust the pH value, the components of the prepared composition interact, and the whitening and freckle removing effects are achieved from multiple aspects of ultraviolet resistance, oxidation resistance, inflammation resistance and skin metabolism improvement.

The invention discloses a composite film based on light-biological synergistic gradient degradation and a preparation method thereof, the composite film sequentially comprises a light response layer, a transition layer and a biological response layer from outside to inside, and the light response layer comprises a polycaprolactone matrix, a tetraphenylporphyrin iron photosensitizer and anatase type TiO2 nanorods; the transition layer is a gradient blend of polylactic acid and modified starch; the biological response layer comprises polyhydroxyalkanoate and bacterial cellulose nanofibers; through the design of the three-layer gradient structure and the construction of the bionic microchannel, the synergistic effect of light degradation, hydrolysis and biodegradation is realized; the composite membrane has excellent mechanical properties and environmental adaptability, the degradation period can be accurately regulated and controlled within 30-180 days, and the soil degradation rate within 60 days reaches 91% or above; the preparation method comprises the processes of electrostatic spinning, gradient co-extrusion and bacterial cellulose in-situ culture. The material can be widely applied to the fields of agricultural mulching films, food packaging and the like, and the problems that a traditional degradable film is poor in mechanical property and uncontrollable in degradation are solved.

The invention provides a soil conditioner for improving soil hardening and a preparation method thereof, and relates to the technical field of soil conditioning. The soil conditioner is prepared by combining nano silicon dioxide, a straw retting material, a straw composite fermentation material, biochar, a water-retaining agent and modified starch. The straw composite fermented material is prepared by the following steps: crushing straws, mixing with sweet water, stirring, drying, carrying out microwave treatment, mixing with bacillus thuringiensis, fermenting, sterilizing, subsequently adding a composite microbial agent of bacillus subtilis, trichoderma and bacillus mucilaginosus, continuously fermenting, and drying. The modified starch is prepared by semi-gelatinizing corn starch and then carrying out microwave drying and shaping. According to the present invention, the defects in the prior art are overcome, the soil hardening phenomenon can be rapidly improved with the small addition amount, the soil porosity is increased, the activity and the diversity of the soil microorganisms are ensured, and the soil fertility is improved.

The invention provides a bio-based composite liquid mulching film and a preparation method thereof. The bio-based composite liquid mulching film comprises a nanocellulose solution, modified starch, modified chitosan, glycerol and calcium carbonate, the modified starch is obtained by modifying starch with citric acid; the modified chitosan is obtained by grafting and copolymerizing chitosan with an acrylic monomer. According to the invention, a plurality of bio-based components such as modified starch, modified chitosan, a nanocellulose solution, glycerol and calcium carbonate are integrated, and natural characteristics of bio-based materials are utilized to form a uniform and degradable film layer; the soil moisture retention film can better isolate air and moisture loss, improves the soil moisture retention ability, ensures sufficient strength and flexibility in the application process, and avoids the problems of early cracking or deformation and the like.

The present invention discloses a livestock and poultry manure biochar-based fertilizer, comprising the following raw materials in parts by weight: 10-42% of dilute protein solution and collagenase-modified livestock and poultry manure biochar, 20-40% of urea, 7-25% of diammonium phosphate, 7-24% of potassium chloride or potassium sulfate, 0.5-1% of modified starch, and 6-23% of bentonite. The livestock and poultry manure is selected from one of chicken manure, cow manure, and pig manure. After the biochar is modified with collagenase, the surface of the biochar has more phenolic hydroxyl groups, carboxyl groups, aldehyde groups, and hydroxyl functional groups, which are effective for NH4 + , PO4 3‑ , K + , has a stronger adsorption effect, collagenase modification makes the protein distribution more uniform, and the generated groups form a stable chemical bond with the biochar surface: it improves the dispersibility of the modified biochar in aqueous solution and reduces agglomeration; it has better chemical stability in acidic and alkaline environments.

The invention discloses a preparation method of high-viscosity cationic starch, which belongs to the technical field of modified starch, and comprises the following steps: crosslinking epichlorohydrin, ball-milling and cationizing; the epoxy chloropropane crosslinking comprises the following steps: mixing starch, calcium hydroxide and deionized water, stirring at 40-50 DEG C, adding sodium stearoyl lactylate, stirring at 50-55 DEG C, naturally cooling to room temperature, adding sodium chloride and epoxy chloropropane, stirring, dropwise adding a potassium hydroxide aqueous solution, stirring, adjusting the pH value to 6, filtering, taking filter residues, washing and drying to obtain crosslinked starch; in the step of ball milling, calcium hydroxide, sucrose fatty acid ester SE-11 and deionized water are mixed and then subjected to ball milling, and a ball-milled material is obtained; the prepared high-viscosity cationic starch is high in paste liquid viscosity and cationic substitution degree, good in paste liquid viscosity stability, uniform in substitution degree and paste liquid viscosity, high in reaction efficiency in cationization and low in alkali consumption.

The invention relates to the technical field of fertilizers, in particular to a urea-containing slow-release coated fertilizer and a preparation method thereof. The urea-containing slow-release coated fertilizer comprises urea particles and a bio-enzyme polyurethane coating layer coated on the surfaces of the urea particles, and the bio-enzyme polyurethane coating layer comprises the following components in parts by mass: 10-20 parts of urea particles, 10-20 parts of urea particles and 10-20 parts of urea particles. Comprising the following raw materials: 20 to 25 parts of castor oil, 18 to 25 parts of castor oil-based polyester polyol, 25 to 30 parts of hydrophobic modified starch, 16 to 22 parts of diphenylmethane diisocyanate, 0.03 to 0.05 part of a catalyst, 1.5 to 2 parts of a dispersant, 1.5 to 2 parts of a high-temperature-resistant bio-enzyme, 2 to 3 parts of glycerin and 14 to 18 parts of N, N-dimethylformamide. The polyurethane coating layer material of the bio-enzyme is prepared through the cross-linked network design of the molecular level and the collaborative regulation and control of the macroscopic coating layer thickness, the balance among efficient nitrogen utilization, environmental friendliness, mechanical properties and weather resistance is achieved, and a solution with technical innovation and practical value is provided for the field of slow-release fertilizers.

The application discloses a salt-tolerant modified cationic starch-based flocculant and a preparation method and application of the flocculant in flocculation and recovery of microalgae, and belongs to the technical field of flocculation materials. The preparation method comprises the following steps: (1) mixing and stirring an alkali solution and starch, then adding a modifier solution of dodecyl succinic anhydride (DDSA), mixing and reacting, and finally washing and drying to obtain modified starch; and (2) mixing and stirring an alkali solution and the modified starch obtained in the step (1), then adding glycidyltrimethylammonium chloride (GTA), mixing and reacting, and finally washing and drying to obtain the product. The starch is modified by GTA and DDSA to be cationic and hydrophobic, and a salt-tolerant modified cationic starch-based flocculant is successfully prepared. The flocculant has good salt tolerance in microalgae flocculation and recovery, and can still achieve a recovery rate of more than 80% under high salinity, and the flocculant has excellent economic value.

The invention relates to the technical field of adhesives, in particular to a starch adhesive for artificial boards and a preparation method of the starch adhesive, and the starch adhesive comprises the following components in parts by weight: 100 parts of modified konjac starch, 15-25 parts of polyvinyl alcohol, 8-12 parts of polyacrylate, 0.1-0.3 part of a preservative, 3-6 parts of epoxy chloropropane, 0.5-1.0 part of a viscosity stabilizer, 2-4 parts of a modified rare earth compound and 180-220 parts of water. According to the invention, a composite adhesive system of'modified starch matrix + chemical cross-linked network + rare earth coordination interface 'is constructed, so that the water resistance and the bonding strength can be obviously improved; meanwhile, the formaldehyde emission is zero, the problem of formaldehyde pollution of urea-formaldehyde resin, phenolic resin and other traditional adhesives is avoided, and an adhesive solution with high performance and environment-friendly characteristics is provided for the artificial board industry.

The invention discloses a modified starch fiber-based degradable plastic and a preparation method thereof, and belongs to the technical field of bioplastics, citric acid is adopted to improve the interaction between starch and epoxidized soybean oil, borax is used as a cross-linking agent to further improve the compatibility between the starch and citric acid-epoxidized soybean oil oligomer, and the modified starch fiber-based degradable plastic is prepared. The modified starch fiber-based degradable plastic is obtained, finally, the degradable plastic film is prepared through a hot press molding method, the degradable plastic film has good tensile strength, elongation at break and degradation capacity, borax serves as a cross-linking agent and can be complexed with hydroxyl of starch to form a ligand, and a multi-core complex of a net structure is formed. The borax can also form a coordinate bond with hydroxyl or carboxyl of citric acid or generate a polymerization reaction, so that the compatibility of the starch and the citric acid-epoxidized soybean oil oligomer is further improved.

The invention relates to the technical field of adhesives, and particularly discloses a low-formaldehyde environment-friendly adhesive and a preparation method thereof. The invention relates to a low-formaldehyde environment-friendly adhesive which is prepared from the following raw materials in parts by mass: 30-50 parts of modified starch, 15-25 parts of vegetable protein, 5-10 parts of modified nano cellulose, 2-5 parts of a composite cross-linking agent and 80-150 parts of water, the composite cross-linking agent comprises amino silane and polyaspartic acid; the modified starch is prepared by performing graft copolymerization on starch subjected to enzymolysis by alpha-amylase and composite anhydride; the vegetable protein is subjected to alkalization and heat treatment before being used; the modified nano-crystalline cellulose is prepared by performing ring-opening etherification reaction on nano-crystalline cellulose, epoxypropane and ethylene oxide in sequence. The low-formaldehyde environment-friendly adhesive prepared by the invention has relatively good bonding strength and relatively low formaldehyde emission.

The invention provides an amino acid compound fertilizer for improving nitrogen and phosphorus utilization rate and a preparation method. The compound fertilizer is based on urea, ammonium sulfate, monoammonium phosphate and potassium chloride according to a specific proportion, glutamic acid / glycine compound amino acid and iron, zinc and boron trace elements are added, and the 18-12-18 proportioning fertilizer with a slow release function is formed through the synergistic effect of amino acid chelation pretreatment and a high tower granulation process. Amino acid competitive inhibition phosphorus immobilization and activation of crop nitrogen metabolic pathways are utilized, a porous coating structure is constructed by means of a modified starch binder, the technical effects that the nitrogen utilization rate is increased by 4% or above and the phosphorus utilization rate is increased by 6% or above are achieved, and the bottleneck of nutrient waste of traditional balanced fertilizers is broken through.

The invention discloses a high-load starch-based steady-state morinda citrifolia enzyme spray-dried microcapsule and a preparation method thereof, belongs to the technical field of food spray drying, and provides the high-load starch-based steady-state morinda citrifolia enzyme spray-dried microcapsule which comprises morinda citrifolia enzyme and modified starch N-zorbit M / porous starch. The preparation method comprises the following steps: stirring and mixing the morinda citrifolia enzyme and the wall material according to different proportions to obtain a morinda citrifolia enzyme and wall material mixed solution; and carrying out spray drying on the morinda citrifolia enzyme mixed solution to obtain the high-load starch-based morinda citrifolia enzyme spray-dried microcapsule. Modified starch N-zorbit M / porous starch is used as a wall material to prepare the high-load morinda citrifolia enzyme spray-dried microcapsule, so that the volatile unpleasant odor of morinda citrifolia enzyme is reduced, and the total phenol content and the oxidation resistance of the morinda citrifolia enzyme are improved.

The invention belongs to the field of composite materials, and discloses a degradable composite film material and a preparation method thereof.The preparation method comprises the steps that under the inert atmosphere, starch is modified through ultraviolet radiation and then mixed with a complexing plasticizer to obtain a mixture, then a silane activation solution is added, and heating and stirring are conducted to obtain a modified starch solution; in an inert atmosphere, melting the modified starch solution and a polymer at 150-180 DEG C in different temperature zones, adding a nano filler, and mixing to obtain a compound; and adding the compound into a film blowing machine to obtain a composite film, and carrying out heat treatment on the composite film to obtain the degradable composite film material. According to the method, the mechanical property and hydrophobicity of the degradable composite film are improved.

The invention discloses a composite flocculant for adsorbing, flocculating and settling Ca < 2 + > in a water body and a method for removing high-concentration Ca < 2 + > in wastewater, and belongs to the technical field of wastewater treatment.The composite flocculant comprises sodium carbonate, magnetic seeds and organic acid modified starch; the magnetic seeds and the organic acid modified starch in the composite flocculant can synergistically promote the formation of magnetic flocs under the stirring action, and the sedimentation rate is increased; the organic acid modified starch and Ca < 2 + > form a stable chelation structure through the coordination and complexation of internal hydroxyl groups and acid radicals, and finally Ca < 2 + > is removed; the organic acid modified starch can flocculate and adsorb calcium carbonate and magnetic seeds at the same time, and recycling and reusing of the magnetic seeds are facilitated while calcium carbonate is settled. The modified starch flocculant and the magnetic flocculation technology provided by the invention can well remove impurities in wastewater; especially for excessive calcium ions, the method not only can improve the removal rate, but also can reduce the flocculation cost, and is suitable for popularization in industrial wastewater treatment.

The invention provides a starch-based soft capsule composition, a starch-based soft capsule and a preparation method of the starch-based soft capsule, and belongs to the technical field of medicines. The starch-based soft capsule composition is characterized by being prepared from the following components in parts by weight: 50 to 100 parts of plant starch, 20 to 100 parts of modified starch, 0.1 to 5 parts of thickening agent and 0.1 to 5 parts of plasticizer, the plant starch comprises pea starch and corn starch in a mass ratio of (10-60): (40-50); the modified starch comprises modified corn starch and modified potato starch in a mass ratio of (1-5): (1-8). The starch-based soft capsule disclosed by the invention is high in joint closing rate; the starch-based soft capsule is high in transparency, not easy to age and good in stability after being stored for a long time.

The invention discloses a bio-based polymer emulsion as well as a preparation method and application thereof, and belongs to the technical field of aqueous polymer emulsions. The emulsion comprises an aqueous continuous phase, bio-based polymer particles, a stabilizing system, and a bionic catechol adhesion component. Specific modified starch is innovatively utilized for assistance, and a bionic adhesion shell layer is constructed on the surface of a bio-based polymer core in situ. Compared with similar products in the market that adhesion to inert substrates can be improved only by adding a large amount of tackifying components, the scheme has the advantages that excellent dry and wet adhesion can be realized on the surfaces of difficult-to-adhere substrates such as polypropylene and polyethylene only by constructing an extremely thin interface functional layer, and the functionalization efficiency and economical efficiency of the bio-based material are greatly improved. Meanwhile, the system effectively overcomes the industrial problem that the high-solid-content emulsion is easy to settle, has excellent storage stability and construction adaptability, and conforms to the development trend of sustainable barrier packaging and high-performance water-based coatings in the future.

The invention provides a high-barrier nanocellulose-based liquid mulching film and a preparation method thereof. The high-barrier nanocellulose-based liquid mulching film comprises a carboxylated nanocellulose solution, hydrophobic modified starch, a compound emulsifier, glycerol, xanthan gum and potassium humate, the carboxylated nano-cellulose solution is obtained by carboxylating and modifying a nano-cellulose solution through succinic anhydride; the compound emulsifier comprises rosin glyceride, polyethylene glycol 400 and nano silicon dioxide; the hydrophobic modified starch is obtained by sequentially carrying out hydrophobic modification on starch through dodecyl glycidyl ether and crosslinking with glycerol triglycidyl ether. The liquid mulching film provided by the invention has excellent barrier property, mechanical strength and environmental adaptability, the effective covering time in a field is remarkably prolonged, and the repeated application requirement caused by rapid damage of a film layer is reduced.

The utility model relates to the technical field of packaging paperboards, in particular to a waterproof and moistureproof environment-friendly packaging paperboard which comprises a base material layer, a waterproof layer and a moistureproof layer, the waterproof layer is arranged on the outer side of the base material layer and made of a mixture of nano silicon dioxide and natural wax, and the moistureproof layer is arranged on the outer side of the waterproof layer and made of a mixture of nano silicon dioxide and natural wax. The waterproof layer is made of a composite material of modified starch and cellulose derivatives, the waterproof layer and the moisture-proof layer are connected through a nano-microporous structure, the nano-microporous structure is filled with a moisture absorbent, a groove is formed in the surface of the base material layer, the groove is filled with reinforced fibers, and a biodegradable film is further arranged between the waterproof layer and the base material layer. The waterproof and moistureproof environment-friendly packaging paperboard not only has excellent waterproof and moistureproof performance, but also meets the environment-friendly requirement, the production process is safe and harmless, meanwhile, the paperboard retains good air permeability and printing adaptability, and is suitable for various packaging requirements.

The invention belongs to the technical field of building materials, and particularly relates to a silane modified starch-based polycarboxylate superplasticizer and a preparation method thereof. The water reducing agent is prepared by taking renewable sulfonated starch as a raw material, performing graft modification through vinyltriethoxysilane (A151), introducing active double bonds into starch molecules, and then copolymerizing with monomers such as isopentenol polyoxyethylene ether (TPEG) and acrylic acid. Compared with the prior art, the mixing amount of the vinyltriethoxysilane (A151) is only 1%-5% of the mass fraction of the acrylic acid, the mixing amount is low, and the cost is saved; the water reducing and dispersing performance of the starch-based polycarboxylic acid water reducing agent is improved, and a certain viscosity reducing effect is achieved.

The application provides a starch-indole acid derivative and a preparation method and application thereof, and relates to the technical field of modified starches. The starch-indole acid derivative refers to esterified starch generated by esterification reaction of starch, a condensing agent and alkali and indole acid. The starch-indole acid derivative has high resistance and can resist degradation of the stomach and small intestine. After reaching the colon site, the starch-indole acid derivative can be fermented by intestinal flora to release indole acid beneficial to intestinal health. Compared with traditional drug delivery modes such as intragastric administration and intraperitoneal injection, the starch-indole acid derivative has obvious advantages and can significantly increase the content of indole acid in the colon and hepatic portal vein blood. In addition, indole acid can activate an aromatic hydrocarbon receptor to play an immunoregulatory role. The immunoregulatory role of indole acid is superimposed on the regulation role of short-chain fatty acids released by starch fermentation by intestinal flora, so that a product playing an immunoregulatory role through multiple immune system signal pathways is provided.

The invention discloses a processing technology of instant quinoa seedling sprout pre-conditioning food, and belongs to the technical field of quinoa seedling sprout compound food. The processing technology comprises the following three steps: S1, raw material pretreatment: performing cleaning, blanching, cooling, enzymolysis and freeze-drying and crushing on quinoa seedlings to obtain powder, performing pre-gelatinization and colloid compound modification on starch-containing food materials to obtain modified starch, and emulsifying grease-containing powder to form a first modified starch-grease compound with the modified starch and the like; s2, mixing the raw materials, namely mixing the quinoa seedling bud powder with the modified starch, and adding calcium chloride, glutamine transaminase, a first modified starch-grease compound and the like; and S3, granulating and curing, namely adding trehalose and the like for granulating, and carrying out microwave and gradient drying. The processing technology provided by the invention can solve the problems of caking, oxidation layering and structure cracking when quinoa is compounded with high-starch and high-fat food materials, and the product quality is remarkably improved.

The invention belongs to the technical field of preparation of molecular materials and adhesive tapes, and discloses a degradable mylar adhesive tape and a preparation method thereof, the degradable mylar adhesive tape comprises a degradable base material layer and a degradable adhesive layer; the degradable base material layer is prepared from the following raw materials in parts by mass: 25-35 parts of poly (butylene succinate) (PBS), 20-30 parts of polylactic acid (PLA), 10-15 parts of polycaprolactone (PCL), 8-12 parts of modified bamboo fiber powder, 3-5 parts of a compatibilizer and 0.5-1 part of an antioxidant; the degradable adhesive layer is prepared from the following raw materials in parts by mass: 40 to 50 parts of a modified starch-based adhesive, 15 to 25 parts of poly (butylene adipate-co-terephthalate) (PBAT), 10 to 15 parts of polyhydroxyalkanoate (PHA), 5 to 8 parts of sodium alginate-chitosan composite gel, 5 to 8 parts of an epoxypropane modifier, 1 to 2 parts of a cross-linking agent and 0.3 to 0.5 part of a de-foaming agent; by optimizing the raw material composition and the preparation process of the base material and the adhesive, the full-life-cycle degradability of the adhesive tape is realized, and meanwhile, excellent mechanical properties, insulativity and temperature resistance are ensured.

The invention discloses a production process of high-stiffness embossed aluminum foil composite paper. The production process comprises the following steps: (1) selecting and treating raw materials; (2) gluing treatment: uniformly coating the front surface of the lining paper with a modified adhesive by using a coating machine, wherein the modified adhesive comprises modified starch, water, konjac glucomannan, a polyamide curing agent, an accelerant, aluminum sulfate, an AKD emulsion and a defoaming agent; (3) aluminum foil compounding: the aluminum foil is unreeled and attached to the modified adhesive, and then extrusion compounding is performed through a compression roller; (4) embossing and forming: embossing the front surface of the aluminum foil of the aluminum foil composite paper by adopting a heating embossing roller; (5) curing treatment: coating a curing agent on the front surface of the aluminum foil of the aluminum foil composite paper by adopting a micro-concave net roller; and (6) cooling and rolling. The stiffness of the aluminum foil composite paper is effectively enhanced, the bonding capacity between the aluminum foil and the lining paper is enhanced, the smoothness of the surface of the aluminum foil composite paper is remarkably enhanced, the attractiveness is enhanced, and the wear resistance of the aluminum foil composite paper is enhanced.

The invention discloses a method for preparing high-purity quartz sand through reverse flotation, which comprises the following steps: S1, ore pretreatment: pretreating raw ore to obtain quartz sand; the quartz sand obtained in the first step is placed in a flotation tank, the mass concentration of ore pulp is adjusted to be 30%-60%, an adjusting agent is added into the ore pulp, the pH value of the ore pulp is adjusted to be 2-4, then an inhibitor is added, stirring is conducted for 3-5 min, a collecting agent continues to be added, stirring is conducted for 10-20 min, finally a foaming agent is added, air is introduced, reverse flotation is conducted, stirring, foam scraping and washing are conducted, and quartz sand concentrate is obtained; the inhibitor is modified starch with the particle size being smaller than 500 nm and the substitution degree being 0.1-1.0, the dosage is 50-250 g / t, and carboxyl and aldehyde groups are introduced into the modified starch; quartz sand concentrate obtained after flotation is subjected to secondary acid leaching and high-temperature chlorination to obtain high-purity quartz sand, modified starch serves as an inhibitor, meanwhile, hydroxyl (-OH) in starch molecules and the surface of quartz form hydrogen bonds, the surface of the quartz is covered, adsorption of a collecting agent to the quartz is hindered, and quartz loss is reduced.

The invention discloses a Trichoderma harzianum-containing biocontrol fertilizer and a preparation method thereof, and belongs to the technical field of mixed fertilizers, the fertilizer comprises composite matrix particles (containing an organic carrier, an inorganic fertilizer and trace elements), a microsphere coating layer (composed of sodium alginate / chitosan gel microspheres) coated with Trichoderma harzianum on the surface, and a water-soluble fertilizer coating layer (composed of sodium alginate / chitosan gel microspheres) coated with Trichoderma harzianum on the surface, and the outermost layer is a biodegradable protective film (modified starch / PVA / PLA). The preparation method comprises the following steps: granulating a matrix, preparing a bacterial suspension, forming bacteria-containing gel microspheres (the spore recovery rate is greater than or equal to 95%), attaching the microspheres to the matrix, and coating the outer layer. According to the structure, the survival rate of viable bacteria stored at room temperature for 120 days is larger than or equal to 68.3%, the rhizosphere bacterial count is larger than or equal to 4.58 * 10 < 6 > CFU / g soil after the viable bacteria are applied to the soil for 30 days, soil-borne diseases are remarkably inhibited, and the crop yield is increased by 13.5% (cucumber yield is increased by 13.5%).

The invention provides a degradable plastic bag material and a preparation method thereof, and belongs to the field of plastic bag materials. The degradable plastic bag material is prepared from the following chemical components: 40 to 50 parts of polylactic acid, 15 to 25 parts of 3-hydroxybutyrate-co-4-hydroxybutyric acid copolymer, 5 to 15 parts of silane coupling agent modified starch, 3 to 8 parts of acetylated bamboo source nano cellulose, 5 to 15 parts of furan-terminated polylactic acid copolymer, 3 to 8 parts of bismaleimide dodecanedioate, 2 to 6 parts of coffee residue loaded WO3 and TiO2 and 1 to 5 parts of epoxidized soybean oil, the composition comprises the following components in parts by weight: 1-3 parts of sodium alginate microencapsulated lipase, 1-3 parts of quaternary ammonium salt modified hydrophilic kaolin, 0.1-1 part of zinc phenylphosphate and 0.1-0.8 part of polycarbodiimide. According to the application, the balance between the mechanical property and the degradation rate of the plastic bag material is realized through light-enzyme synergistic trigger degradation and dynamic covalent network regulation and control.

The invention belongs to the technical field of high-speed railway ballastless track construction, and particularly discloses an anti-crack functional material for ballastless track roadbed slab concrete and a preparation method of the anti-crack functional material. The anti-cracking functional material provides a whole-course expansion effect and delays early expansion by means of a mode of coating calcium oxide with calcium carbonate and compounding magnesium oxide; the protein modified starch is used as a hydration heat regulation and control layer, so that the regulation and control effect of single starch on cement hydration heat is improved, and a compound expanding agent is slowly released; carbonized and expanded rice husks are used as a biomass water-absorbing and anti-releasing material, so that the self-shrinkage and drying shrinkage of the concrete are reduced; the temperature-sensitive microgel material is used as the outermost layer component, the highest temperature value of the roadbed slab concrete is reduced, the temperature drop shrinkage stress of the concrete is improved, and the temperature shrinkage cracking risk of the roadbed slab concrete is inhibited. Various shrinkage stresses of the roadbed slab are accurately regulated and controlled, the limiting and restraining stress of the prefabricated sleeper and the base on the concrete of the roadbed slab is effectively compensated and improved, and the anti-cracking performance of the concrete of the ballastless track roadbed slab is fundamentally improved.