688results about "Paper material treatment" patented technology

The invention provides loofah sponge nanocellulose hydrogel and a preparation method thereof.The preparation method comprises the following steps that anhydrous citric acid, choline chloride and water are mixed to react, and a ternary eutectic solvent is obtained; dispersing loofah sponge purified cellulose in a ternary eutectic solvent, washing and filtering a product to be neutral, dispersing the product in water, and performing ultrasonic treatment to obtain loofah sponge nanocellulose turbid liquid; dissolving sodium lignin sulfonate and lithium chloride in a sodium hydroxide solution to obtain a precursor solution; mixing the loofah sponge nanocellulose suspension with water, polyacrylamide, ammonium persulfate and N, N-methylene bisacrylamide, pouring the precursor solution into the loofah sponge nanocellulose suspension, uniformly stirring the mixture, pouring the mixture into a mold, and sealing the mold; and forming to obtain the loofah sponge nanocellulose hydrogel. The invention also provides an application of the hydrogel. The hydrogel disclosed by the invention has excellent biocompatibility, mechanical property and conductivity, has a wide application prospect in the field of flexible electronics, and is simple in preparation process, low in cost, green and environment-friendly.

The invention discloses a preparation method of a modified corn straw nanocellulose-based dual-response controlled-release pesticide, and relates to the technical field of resource utilization of agricultural wastes and environmental protection. The method comprises the following steps: extracting nano-cellulose from corn straws, modifying the nano-cellulose with zein, preparing a modified corn straw nano-cellulose-based emulsion carrier, and preparing and evaluating the modified corn straw nano-cellulose-based dual-response controlled-release pesticide. The method verifies the effectiveness of the EDC / NHS cross-linking agent in an alcohol-soluble system, successfully modifies the corn straw nano-cellulose, realizes efficient utilization of waste resources, solves the problems of low utilization rate of traditional pesticides, combustion waste of corn straw and performance limitation of conventional cellulose, and has a wide application prospect. Meanwhile, a novel efficient, environment-friendly and economical dual-response controlled-release pesticide can be obtained, and important guiding significance is achieved for solving the bottleneck problem in the field of pesticide preparations.

According to the high-purity cellulose and the preparation method thereof, a lignocellulose raw material and a green ionic solvent are mixed and heated for a certain time under the stirring condition to obtain slurry, and the green ionic solvent is prepared by heating a hydrogen bond donor and a hydrogen bond acceptor at the temperature of 30-100 DEG C for 0.5-3 h and fully stirring the hydrogen bond donor and the hydrogen bond acceptor; adding a viscosity reduction solvent into the slurry, stirring and filtering to obtain a primary extraction filtrate and residues, washing the residues with the viscosity reduction solvent until a washing solution is colorless, naturally airing or drying the residues to obtain high-purity cellulose, and synthesizing a novel functional green ionic solvent by regulating and controlling chemical structures of hydrogen bond donors and acceptors. A green ionic solvent is utilized to effectively break through the anti-degradation barrier of lignocellulose, and mild and efficient preparation of high-purity cellulose is realized.

The invention belongs to the technical field of papermaking, and particularly relates to a paper pulp pressurized screen and a using method thereof. Comprising an equipment base, a screening tank body is arranged on the equipment base, a screening cavity is formed in the screening tank body and sequentially comprises a heavy slag settling area, an accepted pulp screening area and a light slag floating area from bottom to top in the height direction, the screening cylinder is arranged in the accepted pulp screening area, and the lower portion of the screening cylinder abuts against a first partition plate. The screening drum divides the accepted pulp screening area into a to-be-screened area and a finished screening area, the finished screening area is communicated with the pulp outlet pipe, a screening seam is formed in the side wall of the screening drum, a rotor is rotationally arranged on the inner side of the screening drum, a turbulent flow unit is arranged on the rotor, and the turbulent flow unit can eject pulp on the inner side of the rotor to the screening drum and destroy a pulp layer formed on the side wall of the inner side of the screening drum; and the situation that a relatively stable slurry layer is formed on the inner wall side of the screen cylinder by part of slurry to be screened under the action of centrifugal force, so that new slurry is prevented from being screened through screen seams can be avoided, and the screening efficiency is guaranteed.

The utility model relates to the technical field of fermentation, and discloses a papermaking pulp deslagging device which comprises a deslagging equipment body, the stirring assembly is arranged at the axial position of the deslagging equipment body, the stirring assembly internally comprises a connecting rod used for stirring and dispersing fan blades, and a servo motor used for driving and a rotating shaft used for transmission are further arranged in the stirring assembly; the slag removal assembly is arranged on the inner wall of the bottom of the slag removal equipment body, and the slag removal assembly internally comprises a separation barrel; and the driving assembly is arranged at the top position of the inner wall of the slag removal equipment body and used for driving the separation barrel to rotate, and the driving assembly internally comprises the separation barrel, a transmission gear and a second fixing ring. According to the utility model, the stirring assembly, the deslagging assembly and the driving assembly are arranged, and the relative rotation speed between the dispersion fan blades and the separation barrel is increased through the reverse rotation of the separation barrel and the dispersion fan blades, so that the dispersion degree of the dispersion fan blades on raw materials is improved, and the problem that residues are wrapped in the raw materials and are difficult to remove is avoided.

The invention relates to the technical field of fractionation of lignocellulose biomass, and discloses a method for fractionating lignocellulose biomass by using a eutectic solvent, which comprises the following steps: mixing betaine and malic acid, stirring, and cooling to room temperature after the reaction is finished to obtain a clear and transparent eutectic solvent; the method comprises the following steps: mixing crushed lignocellulose biomass with a deep-eutectic solvent, and putting the mixture into a high-pressure reaction kettle; acetone and n-butyl alcohol are mixed according to the volume ratio of 3: 2-4: 1, and an anti-solvent is prepared; the method comprises the following steps: slowly adding an anti-solvent into a mixture of the lignocellulose biomass and the eutectic solvent, carrying out ultrasonic treatment, and then carrying out suction filtration. The glass electrode pH meter is used for measuring the pH value of the recovered deep-eutectic solvent, and the newly prepared deep-eutectic solvent is added according to the pH value, so that the stability of the solvent performance can be effectively maintained, the deep-eutectic solvent always keeps a good fractionation effect in multiple times of recycling, the utilization rate of the solvent is greatly improved, and the production cost is reduced.

The utility model relates to the technical field of papermaking, in particular to a cellulose cooking device for papermaking, which comprises a cooking vessel, a feed port arranged at the top of the cooking vessel, a discharge port arranged at the bottom of the cooking vessel, a filter sieve arranged in the cooking vessel, a stirring rod arranged in the cooking vessel, and two groups of cleaning mechanisms arranged on the stirring rod, the lifting assembly is arranged on the digester; the rotating assembly is arranged at the bottom of the digester; according to the utility model, through the arrangement of the rotating assembly, the digester can be driven to turn over up and down through the rotating assembly, so that slurry can be turned over back and forth to form a good circulation capability, and through the arrangement of the lifting assembly at the top of the stirring rod and the arrangement of the cleaning mechanism on the stirring rod, when the slurry is stirred by the stirring rod, the slurry can be cleaned. The lifting assembly drives the stirring rod to move up and down, the cleaning mechanism can move back and forth along the filter sieve and the bottom of the digester, and scaling is prevented.

The present invention provides a deep eutectic solvent and its preparation and application. The deep eutectic solvent comprises choline chloride, p-toluenesulfonic acid, 1,4-butanediol, and water; wherein the molar ratio of choline chloride, p-toluenesulfonic acid, and 1,4-butanediol is 1-2:3-6:2-8, and the ratio of the total mass of choline chloride and p-toluenesulfonic acid to the mass of water is 20:9-11. When used for the pretreatment of Miscanthus sinensis, the deep eutectic solvent of the present invention can effectively remove hemicellulose and lignin from the cell walls of Miscanthus sinensis, thereby significantly improving the efficiency of its enzymatic hydrolysis of cellulose.

The utility model relates to the technical field of paper pulp pressurized screens, in particular to a paper pulp pressurized screen for papermaking, which comprises a barrel with a rotor and a screen inside, and a pulp inlet pipe, a dilution water pipe and a controller are arranged on the barrel. A first pressure gauge used for detecting the internal pressure of the screen and a second pressure gauge used for detecting the position between the screen and the inner side wall of the barrel are further arranged on the barrel, a first valve used for controlling the flow of the pulp inlet pipe is arranged on the pulp inlet pipe, and a second valve used for controlling the flow of the dilution water pipe is arranged on the dilution water pipe; the input end of the controller is connected with the first pressure sensor and the second pressure sensor and used for receiving pressure signals obtained by the first pressure sensor and the second pressure sensor, the output end of the controller outputs control signals, and the control signals are used for controlling the flow of the first valve and the flow of the second valve. The problem that in the screening process of a paper pulp pressurized screen in the prior art, a screen is prone to being blocked, and consequently the screening effect is poor is solved.

The invention discloses a preparation method of a pesticide droplet stabilizer based on corncobs, and in order to realize high-value utilization of the corncobs, the method mainly comprises the following steps: pretreatment of the corncobs, acquisition of corncob cellulose, extraction of cellulose nanocrystals, and extraction of cellulose nanofibers. Characterization of a corncob nanofiber stabilizer and preparation and testing of a corncob-based pesticide droplet stabilizer. The natural cellulose nanocrystals and cellulose nanofibers can be successfully extracted from the corncobs through the method, and the method can be applied to stabilization of pesticide liquid drops and stabilization of the pesticide liquid, which is of great significance to high-value utilization of the corncobs and stabilization of the pesticide liquid.

The invention provides a method for carbon dioxide assisted organic solvent vapor-liquid phase oriented separation of wood fiber biomass, and belongs to the technical field of wood fiber biomass chemical engineering. According to the method, carbonic acid formed by CO2 and water is used as a mild and recoverable acid catalyst source, the CO2 cooperates with the extraction solvent to dissolve lignin and hemicellulose components, and vapor-liquid phase exchange of the extraction solvent is controlled by regulating and controlling the temperature change in the extraction process; the directional migration of components dissolved from lignocellulose in the vapor-phase solvent to the liquid-phase solvent is realized, the repeated recycling of the extraction solvent is realized, and the overall dosage of the extraction solvent in the treatment process is reduced. A large amount of dissolved lignin is finally enriched in a liquid phase part of the extraction solvent at the bottom of the reaction container along with phase conversion of the extraction solvent, and a cellulose component is retained in a solid phase material. The method provided by the invention not only realizes better lignin separation efficiency, but also greatly reduces the use amount of the extraction solvent.

The present invention discloses a process for preparing lactic acid by mechanically enhanced ammonia method from straw-like biomass. The enzymatic hydrolysate of solid fibers obtained by the mechanically enhanced ammonia method from straw-like biomass is used as the carbon source of the fermentation medium in the process of fermenting lactic acid. The preparation of the carbon source in the fermentation medium comprises the following steps: S1: treating straw-like lignocellulosic biomass with a pretreatment liquid containing ammonia water and inorganic ammonium salts in a twin-screw device; S2: subjecting the obtained material to a heat preservation reaction, and after solid-liquid separation, obtaining solid fibers containing holocellulose; S3: enzymatically hydrolyzing the obtained solid fibers with Trichoderma reesei cellulase and xylanase, and performing solid-liquid separation, and the obtained supernatant is used as the carbon source in the fermentation medium for fermenting L-lactic acid. The present invention uses the sugar liquid obtained by enzymatic hydrolysis and saccharification of pretreated holocellulose, inoculates Bacillus coagulans to ferment L-lactic acid after supplementing nitrogen source and inorganic salts, and can greatly improve the concentration and conversion rate of L-lactic acid.

The invention discloses a method for rapidly preparing carboxymethyl cellulose from corn straw, and belongs to the technical field of plant straw comprehensive utilization and green separation engineering. According to the method, the ionic liquid is used as an extraction solvent, and microwave-assisted treatment is combined in a corn straw cellulose component separation stage, so that the corn straw cellulose component can be rapidly extracted and separated; ultrasonic-assisted treatment is combined in the cellulose alkalization and etherification stages, and carboxymethyl cellulose can be efficiently prepared through the alkalization, etherification and other reaction processes of cellulose. Compared with a single technology, the strategy of coupling the three technologies can obtain carboxymethyl cellulose with higher yield and higher substitution degree. Compared with a traditional hydrothermal method or an enzymolysis method which is high in energy consumption and long in time consumption, the method has the advantages that the whole process is easy to operate, the separation speed is high, performance is stable, and the method is environmentally friendly (the ionic liquid can be recycled) and the like, and has important significance on effective separation and comprehensive utilization of corn straw components.

The invention relates to the technical field of asphalt modification, in particular to plant multi-component extraction and application of the plant multi-component extraction to improvement of the anti-aging performance of asphalt. The extraction method of the plant multi-component extract comprises the following steps: selecting a whole plant or organ tissues of the plant, cleaning with clear water, taking out, peeling to obtain peel, and pulping to obtain pulp; and adding a settling agent into the slurry, stirring, carrying out suction filtration to obtain filter residues, drying, and grinding to obtain the plant multi-component extract. The plant multi-component extract can be used for improving the anti-aging performance of asphalt. The plant multi-component extract modified asphalt is high in storage stability, the anti-aging performance of the asphalt can be obviously improved, meanwhile, the preparation method of the product is simple, convenient, efficient, low in cost, environmentally friendly and free of pollution, and obvious technical and economic benefits are achieved.

The utility model relates to the technical field of papermaking pulp screening, in particular to a screen frame for papermaking fiber separation, a beating device comprises a rotating rod, the rotating rod is rotationally connected between the inner walls of the two sides of a U-shaped frame, a plurality of beating rods are evenly and fixedly installed on the surface of the outer wall of the rotating rod, a sliding groove is formed in the surface of one side of the U-shaped frame, and the beating rods are arranged in the sliding groove. A sliding groove is formed in the U-shaped frame, a moving plate is slidably connected into the sliding groove, a supporting plate is fixedly installed on the surface of one side of the U-shaped frame, an electric telescopic rod is fixedly installed on the surface of the supporting plate, a connecting plate is fixedly installed on the surface of the moving plate, and a rack is fixedly installed on the surface of the end, away from the moving plate, of the connecting plate; and a gear is fixedly mounted on the surface of the outer wall of the rotating rod. According to the screening device, the problem that in the screening process of an existing screening device, slurry often blocks the interior of screen meshes, and the screening efficiency of the screen meshes becomes low is solved.

The embodiment of the utility model provides a bamboo pulp grading screening system which comprises at least two screening units connected in parallel, each screening unit comprises at least two pressure screens connected in series, each pressure screen comprises a screen plate used for separating pulp into long fiber pulp and white water, each screen plate comprises screen holes, the diameter of each screen hole is 0.6-1.1 mm, and the diameter of each screen hole is 0.6-1.1 mm. In the same screening unit, the ratio of the area of the screen plate of the pressurized screen located on the upstream to the area of the screen plate of the pressurized screen located on the downstream is 1: (0.55-0.8), the average length of obtained long fiber pulp is better than that in the prior art through the bamboo pulp grading screening system formed through the arrangement, meanwhile, the screening rate of medium and short fibers is greatly increased, and the system runs stably.

The invention discloses a two-stage slag separator tailing diluting and re-screening device, which relates to the technical field of tailing screening, and comprises a box body, a first screening cavity, a diluting cavity and a second screening cavity, a first screening assembly and a second screening assembly are arranged on the box body; the first screening assembly comprises a first connecting seat, a first screening seat, a first synchronous belt structure and a screening mesh belt; heavy impurities in tailings are screened through the arranged diluting assembly and the arranged first screening assembly, light impurities in the tailings are screened through cooperation of a first screening base, a first synchronous belt structure, a screening net belt and a liquid guide pipe, and the impurities are collected through cooperation of a negative pressure suction nozzle, a negative pressure pipe, negative pressure equipment and a collecting tank; according to the screening device, the supporting plate, the filtering base, the filtering piece, the filtering plate, the first air guiding piece, the second air guiding piece and the driving motor are arranged, collected impurities are cleaned, the first screening assembly does not need to be stopped, the screening effect of the first screening assembly is improved, and the using effect of the screening device is improved.

The utility model relates to a paper pulp deslagging device, and relates to the field of papermaking equipment, the paper pulp deslagging device comprises a tank body, a separation assembly and a deslagging assembly, the top of the tank body is provided with a pulp inlet, the side wall of the tank body is provided with a deslagging port, the deslagging port is provided with an opening and closing door, the bottom of the tank body is provided with a pulp outlet, and the separation assembly and the deslagging assembly are both arranged in the tank body. The separation assembly comprises a filter plate and a centrifugal part, the filter plate is used for filtering large-particle-size impurities in paper pulp, the centrifugal part is used for separating the paper pulp from small-particle-size impurities, the residue discharging assembly comprises a transmission part and a residue conveying part, and the centrifugal part drives the residue conveying part through the transmission part to convey the small-particle-size impurities to the residue discharging opening. The device has the effects that the time consumed by coarse screening and fine screening is shortened, and the residue removal efficiency of paper pulp is improved.

The invention discloses a preparation method and application of bamboo nanocellulose and bi-crosslinking hydrogel. The preparation method of the hydrogel comprises the following steps: (1) dispersing the bamboo nanocellulose; (2) preparing a lignin-Fe solution; and (3) preparation of the bi-crosslinked hydrogel: adding the bamboo nanocellulose suspension and acrylic acid into water, then adding ammonium persulfate and N, N '-methylene bisacrylamide, finally adding the lignin-Fe solution to obtain a precursor solution, and pouring the precursor solution into a mold to obtain the bi-crosslinked hydrogel. The moso bamboo is used as a raw material, cellulose is extracted from the plant which is extremely high in carbon sequestration capacity and rapid in production and then is processed into nano cellulose, a novel utilization way is provided for the moso bamboo, and the hydrogel prepared from the moso bamboo is good in environment friendliness, green, natural and non-toxic, can be in direct contact with skin, and has a good application prospect. And the application and development of the material in the fields of environmental protection, biomedical treatment, electronic skin, wearable sensors and the like are facilitated.

The invention discloses a preparation method of a nano-crystalline cellulose composite raw material containing an antibacterial agent, and relates to the technical field of material preparation, the preparation method comprises preparation of the nano-crystalline cellulose composite raw material, and the preparation method of the nano-crystalline cellulose composite raw material containing the antibacterial agent comprises the steps of raw material preparation, antibacterial agent loading and composite forming. The raw materials comprise a natural fiber raw material, tea polyphenol, a chitosan acetic acid solution, a nano cellulose suspension and plant essential oil, the natural cellulose raw material comprises wood pulp, bamboo pulp and cotton fibers, an antibacterial agent is loaded in-situ polymerization, and the composite molding comprises functional additive mixing and hot press molding drying. In the hot pressing process, nanocellulose molecular chains are rearranged and interwoven under the action of temperature and pressure, meanwhile, reinforcing agents such as lignin and the like are further fused with nanocellulose, and a glycerol plasticizer plays a role, so that the material has better flexibility and plasticity, and finally a compact blocky composite raw material is formed.

The invention relates to the technical field of pulping production, in particular to a spherical digester device for pulping. Comprising a fixing frame, a spherical heat preservation shell is arranged in the fixing frame, a spherical cooking shell is concentrically fixed in the heat preservation shell, rotating shafts are fixed to the two ends of the cooking shell, the rotating shafts penetrate through the heat preservation shell and are rotationally connected with the fixing frame, and a driving unit for driving the rotating shafts to rotate is arranged on the fixing frame. The cooking shell and the heat preservation shell are driven by the motor to rotate integrally, and a multi-dimensional mixed flow field is formed under the action of centrifugal force and gravity in combination with the baffle structures uniformly distributed on the inner circumference. The wood chips and the alkali liquor are repeatedly cut and dispersed by the baffles in the rolling process, the static accumulation and layering phenomena are broken, uniform permeation of fibers and the reaction liquor is achieved, and the cooking reaction time is greatly shortened.

The invention belongs to the technical field of fruit by-product processing, and particularly relates to a method for extracting cellulose, pectin and polyphenol from pear fruit by-products. According to the method, the thermal mechanochemical effect of steam explosion is utilized to perform steam explosion treatment on the pome byproducts, so that most of hemicelluloses and lignin can be removed, cellulose, pectin and polyphenol can be efficiently and quickly extracted, the production cycle of the cellulose, the pectin and the polyphenol is shortened, and the efficiency is improved; in addition, the combination of choline chloride and ethanol is used as the eutectic solvent, compared with other types of hydrogen bond acceptors and hydrogen bond donors, the polyphenol extraction effect is most remarkable, and the extraction efficiency of the pear fruit byproduct polyphenol can be improved to the maximum extent through a simple process. The method provided by the invention lays a foundation for further development and utilization of pear residue cellulose, pectin and polyphenol, and improves the comprehensive utilization rate of pear fruit processing byproducts.

The invention provides nano cellulose as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) carrying out heating reaction on a mixed solution containing a biomass material and a eutectic solvent, and filtering to obtain fibers; (2) mixing the fiber with a solvent, and performing ultrasonic treatment to form the nano cellulose; wherein the eutectic solvent comprises a hydrogen bond donor and a hydrogen bond acceptor, the hydrogen bond donor is selected from 2-aldehyde acetic acid and / or chloroacetic acid, and the hydrogen bond acceptor is selected from choline chloride. The preparation method provided by the invention can effectively reduce the cost and energy consumption for synthesizing the nano cellulose.

According to the method for separating the carbohydrate and the lignin from the lignocellulose provided by the embodiment of the invention, the lignin and the carbohydrate in the lignocellulose raw material are separated by utilizing the choline chloride eutectic solvent, and the lignocellulose raw material is subjected to pretreatment and subsequent separation under a mild condition; the choline chloride deep-eutectic solvent is simple to prepare, good in lignin and carbohydrate separation effect, safe and pollution-free.

The invention discloses a system for removing stickies from paper making pulp, belongs to the technical field related to paper production, and aims to solve the problems that in the prior art, materials with high viscidity, such as pulp with overhigh humidity, are easily adhered to a screen mesh or the inner wall of a centrifugal screen, so that the screening efficiency is reduced, even screen holes are blocked, and the normal screening operation is influenced. Comprising a shell, a round rod is rotationally connected to the shell, a packing auger is installed in a partial area of the round rod, a motor drives the round rod to drive the round rod to rotate, and the round rod can drive multiple sets of scrapers to rotate, so that centrifugal screening operation can be conducted on paper pulp, fluid except for adhesive is screened out, and meanwhile the size of the pulp is reduced. According to the paper pulp screening device, materials attached to an arc-shaped screen plate can be scraped, the materials in paper pulp can be prevented from being attached to the arc-shaped screen plate, the screening efficiency is relatively good, separation of a threaded sleeve and a round rod is utilized, a sleeve can drive a scraper to conduct dismantling work, and independent maintenance is facilitated.

The invention relates to the technical field of sand removing machines, and discloses a papermaking sand removing machine which comprises four stone tables and four main frames, each main frame is installed on the corresponding stone table, a smashing part is installed on the main frames and used for smashing tailing impurities obtained after paper pulp is subjected to sand removing, and a discharging part is installed on the smashing part and used for discharging the tailings impurities obtained after paper pulp is subjected to sand removing. The main frame is used for blocking and guiding tailing impurities after paper pulp sand removal to a crushing process, the precipitation part is mounted on the main frame and used for depositing the tailing impurities after paper pulp sand removal, the impurity removal part is mounted in the precipitation part, and the crushing part is used for crushing the tailing impurities after paper pulp sand removal, so that the impurities are uniform in size and easier to flow; according to the invention, impurities with different sizes are prevented from blocking the precipitation pipeline and the slag discharge pipeline, the crushed mud and sand impurities are uniform, the problems of pipeline blockage and discharge stagnation can be effectively reduced, and the smoothness and the discharge efficiency of the pipeline are improved.

The invention relates to the technical field of agricultural waste treatment, and relates to a composite material prepared by ultrasonic-assisted enzyme treatment of agricultural waste and a method. The method comprises the following steps: plant fiber pretreatment: adding grinding balls into a ball mill, and adding plant fiber powder into the ball mill; drying the sieved product for later use; preparing a buffer solution: dissolving citric acid and sodium citrate with deionized water to obtain an acidic buffer solution; performing ultrasonic-assisted enzyme treatment on fibers: putting the ball-milled plant fiber powder into a beaker, and adding deionized water; uniformly stirring the enzyme solution by using a stirring rod, and then carrying out ultrasonic treatment; centrifuging, taking out precipitate, and drying for later use; and preparation of the plant fiber / PBAT composite material: putting the mixed raw materials into a mold cavity by adopting a hot pressing method, and carrying out compression molding. According to the invention, the chestnut shell fibers are subjected to ball-milling composite ultrasonic-assisted enzyme treatment to obtain the micro-nano plant fibers, so that the plant fibers have the properties of micro-nano materials; the preparation process is simple, the cost is low, and the cost of the PBAT material is reduced.

The invention discloses a cleavable polysaccharide monooxygenase mutant FpLPMO9A-N160T and application of the cleavable polysaccharide monooxygenase mutant FpLPMO9A-N160T, and belongs to the field of enzyme engineering. The optimal temperature of the lytic polysaccharide monooxygenase mutant FpLPMO9A-N160T disclosed by the invention is 50 DEG C, the optimal pH is 5, and the enzymatic activity of the mutant FpLPMO9A-N160T is 10.8 times that of a wild type. The thermal stability of the lytic polysaccharide monooxygenase mutant is remarkably improved, IC50 is 101.1 min at the temperature of 50 DEG C and is 1.57 times that of a wild type, the activity of the mutant can be kept for a longer time at the high temperature, and better thermal stability is shown. The improvement has important significance on the expression of the LPMO in industrial application, especially in environments requiring high-temperature operation, such as biomass conversion, biofuel production and other processes. The higher thermal stability not only prolongs the service life of the enzyme, but also improves the efficiency and reliability of the enzyme in practical application.

The invention discloses cellulose degradation bacillus subtilis, cellulase secreted by the cellulose degradation bacillus subtilis and application of the cellulose degradation bacillus subtilis, and belongs to the technical field of microorganisms. The preservation number of the strain is CCTCC (China Center For Type Culture Collection) NO: M 20242073, and the preservation date is September 25, 2024. The enzyme activity of the cellulase secreted and produced by the strain is 10.93 U / mL. The invention also provides application of the strain in degradation of cellulose. The bacillus subtilis has the beneficial effects that the bacillus subtilis with efficient cellulose degradation capability is provided, and the effectiveness of the bacillus subtilis in the aspect of filter paper degradation is verified. The filter paper degradation rate of the strain reaches 28.7%, so that the strain has a better application prospect in the field of cellulose degradation.

The utility model relates to the technical field of papermaking equipment, in particular to a pressure screen bar structure which comprises a cylindrical screen cylinder, an upper flange and a lower flange are arranged at the two ends of the screen cylinder respectively, a reinforcing ring and middle rings are arranged on the outer wall of the screen cylinder, the reinforcing ring is arranged in the center of the outer wall of the screen cylinder, and a plurality of sets of middle rings are arranged in the axial direction of the screen cylinder at equal intervals. A plurality of bar bodies are fixed on the middle ring and are distributed in a circular array along the central axis of the middle ring, and each bar body comprises a fixed part fixedly connected with the middle ring, an extension part is arranged at one end, facing the rotor wing, of the fixed part, the end face of the extension part is inclined, and the end face of the inclined extension part is gradually close to the rotating direction of the rotor wing. According to the bar structure of the pressure screen, on the basis that the aperture ratio of the screen cylinder is guaranteed, vortexes are prevented from occurring, and therefore the yield is guaranteed.