515 results about "Biomass carbon" patented technology

The invention discloses a zinc-iodine battery positive electrode material based on corn straw shell derived porous carbon and a preparation method of the zinc-iodine battery positive electrode material. According to the material, corn straw shells serve as the sole carbon source, an indigenous nitrogen-doped biomass charcoal carrier with a hierarchical pore structure is prepared through pre-carbonization and KOH activation processes, and the material is characterized in that the specific surface area is larger than or equal to 1500 m < 2 > / g, and the micropore proportion is larger than 90%. The iodine is loaded on the carrier (the iodine content is greater than or equal to 45wt%) through a vacuum sublimation method to form the indigenous nitrogen-doped biomass charcoal / iodine composite material. According to the positive electrode material, through the synergistic effect of physical confinement and pyridine nitrogen chemical adsorption, the multi-iodide shuttle effect is effectively inhibited, so that the capacity retention rate of the zinc-iodine battery is greater than or equal to 93% after 40000 cycles under the current density of 2A g <-1 >, and the capacity retention rate is greater than 45% under the rate of 10A / g. The method has double benefits of agricultural waste resource utilization and high-performance energy storage device development.

The invention relates to the technical field of carbon sink calculation, in particular to a forestry carbon sink calculation model, a forestry carbon credit calculation method and a storage medium. The model comprises an overground biological carbon sink amount estimation module used for calculating overground biological carbon sink data of a target area, an underground soil carbon sink amount estimation module used for calculating soil carbon sink data of the target area, and a litter carbon reserve estimation module used for calculating litter carbon sink data of the target area. The combined loss calculation module is used for calculating carbon loss data; and the final carbon sink total quantity fusion module is used for calculating the carbon sink quantity according to the aboveground biological carbon sink data, the soil carbon sink data, the litter carbon sink data and the carbon loss data. A forestry carbon sink calculation model based on multiple dimensions is established through multiple types of carbon sink estimation modules, and the problem that the requirement for rapid authentication of the global carbon market cannot be met due to high manual dependency is solved; the problems of low calculation precision, high cost and the like caused by insufficient model dynamics, single model calculation dimension and the like are solved.

The present invention discloses a method for preparing a flexible polyaniline / biomass carbon electromagnetic shielding material. After high-temperature carbonization of a fiber fabric, a structurally ordered biomass carbon matrix is ​​obtained. Under the synergistic action of an oxidant and a dopant, aniline monomer is in situ oxidatively polymerized to generate polyaniline that is adsorbed on the surface of the biomass carbon matrix, thereby obtaining the polyaniline / biomass carbon electromagnetic shielding material. The electromagnetic shielding material of the present invention has an intricate and ordered two-dimensional network structure, which helps to establish a conductive network and exhibits excellent electromagnetic shielding effectiveness. In addition, the unique flexibility can fully meet the special requirements of flexible wearable electronic devices, electromagnetic shielding clothing fillers, etc. for the performance of electromagnetic shielding materials. The synthesis process of this method is safe and environmentally friendly, and the required consumables are cheap and abundant, making it suitable for commercialization and industrialization requirements.

The invention discloses a preparation method for preparing a biomass porous carbon material through high-temperature carbonization of molten salt and application of the biomass porous carbon material, and belongs to the technical field of synthesis of inorganic functional materials. According to the technical scheme, the method is characterized in that sodium chloride and potassium chloride are mixed into mixed salt according to different proportions, then the mixed salt is mixed with enteromorpha biomass according to a certain proportion, the mixture is placed in a porcelain crucible, the mixed salt is added for covering, the porcelain crucible is placed in a muffle furnace to be heated and carbonized, and the porous biomass carbon material is obtained after water washing and drying. The enteromorpha biomass is selected as the raw material, the operation is simple and controllable, the cost is low, batch production can be realized, and the prepared novel porous biomass carbon material has a complex porous structure, a large specific surface area, a very good catalytic effect, strong adsorption capacity and good conductivity, and shows excellent performance when being applied to the field of advanced oxidation.

The invention belongs to the field of battery materials, and discloses a ferric sodium pyrophosphate material as well as a preparation method and application thereof. The preparation method of the ferric sodium pyrophosphate comprises the following steps: step 1, mixing a phosphorus source, an iron source, a sodium source, a biomass carbon source and an alcohol additive, and uniformly stirring to obtain a mixed material A; step 2, carrying out hydrothermal reaction on the mixed material A, and then centrifuging and drying to obtain an intermediate product B; and 3, roasting the intermediate product C in a protective atmosphere to obtain the carbon-coated ferric sodium pyrophosphate. A three-dimensional conductive network is formed after the biomass carbon source and the NFPP are compounded, the interface resistance is reduced, the charge transfer efficiency is improved, and after the biomass carbon source is carbonized, biomass carbon with mechanical supporting and buffering effects can relieve volume expansion of the NFPP in the charge-discharge or reaction process and inhibit material pulverization, so that the cycling stability is improved.

The invention relates to the technical field of electro-catalysis, in particular to a modified iron monatomic catalyst based on biomass carbon as well as a preparation method and application of the modified iron monatomic catalyst. The preparation method comprises the following steps: mixing and stirring chitosan, an acetic acid solution, thiourea and ferric chloride, adjusting the pH value to 7.5-8.5, and freeze-drying to obtain an aerogel precursor; pre-carbonizing the aerogel precursor to obtain a pre-carbonized product; mixing the pre-carbonized product with an alkali reagent, and calcining to obtain a metal nanoparticle doped monatomic catalyst; and carrying out ultrasonic treatment on the metal nanoparticle doped monatomic catalyst by using a mixed acid solution, washing to be neutral, and drying to obtain the modified iron monatomic catalyst. By adopting the modified iron monatomic catalyst provided by the invention, non-polar CO2 molecules and NO3 <-> are efficiently converted into urea under mild conditions, the yield of the urea is up to 2978.6 mu g h <-1 > mgcat <-1 >, and the maximum Faraday efficiency is up to 30.4%.

The invention discloses a method for preparing a silicon-carbon composite negative electrode material through an electrostatic self-assembly technology, and belongs to the technical field of lithium ion battery negative electrode materials. According to the invention, lignin is used as a biomass carbon source and lauryl sodium sulfate (SDS) and poly (diallyldimethylammonium chloride) (PDDA) are used as activators through a simple electrostatic self-assembly technology; a proper amount of nano silicon and PDDA are subjected to in-situ adsorption, and lignin and SDS are subjected to in-situ adsorption; a self-assembly process is carried out through the positive and negative charge attraction effect among colloidal particles, so that effective compounding of the nano silicon particles and the biomass carbon is realized; and performing vacuum drying, and performing one-stage sintering in a tubular furnace to obtain the silicon-carbon composite negative electrode material. Based on the problems of non-uniform particle size, easy agglomeration and great abrasion of a silicon-carbon composite material in a traditional mechanical synthesis technology, the invention improves the compounding efficiency of the silicon-carbon material and improves the problems of volume expansion of a silicon negative electrode, slow migration rate of lithium ions, poor cycle performance and the like.

The invention discloses a lycium ruthenicum biomass carbon dot as well as a preparation method and application thereof. The novel lycium ruthenicum carbon dots are prepared by taking lycium ruthenicum as a raw material and adopting a one-step hydrothermal method, and the novel lycium ruthenicum carbon dots are used for detecting residual herbicides in soil without being interfered by other substances. The method for detecting the herbicide residues in the soil by adopting the prepared novel carbon dots is superior to a large instrument, the detection method has the advantages of simplicity in operation, low cost, high sensitivity and the like, the source of the lycium ruthenicum is wide, and the preparation process is green and environment-friendly. Therefore, the prepared carbon dots provide a new method for detection of the fine phosphinate ammonium salt, and a thought and a method are provided for specific application in agricultural production.

The invention discloses a biomass-based hard carbon composite material quantitatively prepared based on a hard carbon pore volume and a method thereof, a negative electrode material and a battery. The method provided by the invention comprises the following steps: firstly, uniformly dispersing a pore-forming agent in biomass powder, pre-carbonizing, and washing to obtain a porous carbon matrix; according to the steps, pore forming is completed while pre-carbonization is completed, the porous carbon matrix with a certain pore volume is prepared, the dosage of the soft carbon precursor is designed based on the total pore volume in the subsequent steps, quantification and rationalization of the dosage of the soft carbon precursor can be achieved, the obtained product is good in performance consistency, and industrial production can be achieved. And the problem that subsequent soft carbon raw materials cannot be scientifically matched due to diversity of raw materials of biomass with different sources can also be avoided. Besides, by utilizing the chemical cross-linking reaction of asphalt and biomass carbon, not only is the carbon residue rate improved, but also a unique structure rich in closed pores and ultra-micropores is constructed, and the problems of low initial coulombic efficiency and insufficient platform capacity of traditional hard carbon are effectively solved.

The invention provides a composite porous carbon material and a preparation method thereof, and a silicon-carbon negative electrode material and a preparation method thereof, and belongs to the technical field of silicon-carbon negative electrode materials. Liquid resin, biomass carbon and carbon nanotubes are fully mixed in an organic solvent, a high-strength spherical porous carbon material is obtained through processes of spray drying, carbonization, activation and the like, and finally the silicon-carbon negative electrode material is obtained through silicon deposition and carbon coating. The resin coating, the carbon nanotubes and the spherical structure cooperate with one another, so that the strength of the porous carbon structure is greatly enhanced; the high-strength porous carbon base material can effectively relieve the problem of pore fracture caused by silicon expansion and high compaction of the pole piece, improve the first efficiency and slow down long-cycle capacity attenuation.

The invention discloses a preparation method and application of a biomass-based hard carbon negative electrode material based on a microwave solvothermal method, and the preparation method comprises the following steps: fully mixing a pretreated biomass carbon source with a sulfuric acid solution, transferring into a microwave hydrothermal reaction kettle, and carrying out microwave hydrothermal treatment to obtain a hydrothermal reaction product; carrying out solid-liquid separation on a hydrothermal reaction product, collecting filter residues, cleaning until filtrate is neutral, and drying to obtain a hard carbon precursor; performing high-temperature carbonization on the hard carbon precursor under the protection of an inert atmosphere to obtain the biomass-based hard carbon negative electrode material; according to the method, a mixed system of the biomass carbon source and sulfuric acid is pre-carbonized in a microwave solvothermal mode, uniform deliming of the biomass carbon source is achieved under the controllable acidity condition, and the uniformity of the biomass carbon source is improved; the pre-carbonized biomass material is subjected to high-temperature carbonization in an inert atmosphere, so that a hard carbon material with a moderate extension interlayer spacing can be obtained, and the synergistic improvement of high-rate charge-discharge performance and long cycle stability is realized.

The invention relates to the technical field of steel sintering processes, in particular to a biomass gasification coupling system for a steel sintering process, which comprises a biomass gasification system, a circular cooler waste heat utilization system and a waste heat power generation system, the biomass gasification system comprises a biomass drying system, a raw material conveying belt system, a biomass gasification furnace, a biomass gas heat insulation combustion chamber, a sintered coke powder preparation system and a biomass gas purification system, and the biomass drying system is used for drying biomass raw materials; and the dried biomass raw materials are conveyed to the biomass gasification furnace through the raw material conveying belt system. According to the coupling system for biomass gasification for the steel sintering process and the control method, biomass serves as zero-carbon energy, and biomass charcoal obtained after biomass gasification can replace part of solid fuel to achieve the carbon reduction effect. Meanwhile, the biomass gasified gas can replace a part of coal gas, and the carbon reduction effect can also be achieved.

The invention relates to the technical field of heavy metal contaminated soil remediation, in particular to a plant-microorganism-passivator synergistic remediation method for a heavy metal contaminated farmland, which comprises the following steps: step 1, constructing a soil digital twinborn model; step 2, intelligent decision making and verification of a collaborative restoration scheme; 3, soil pretreatment before remediation; step 4, hierarchical collaborative restoration and dynamic regulation and control; 5, performing long-term verification on the repair effect and performing model iteration; physical heat treatment is used as strengthening pretreatment, the occurrence form of heavy metal is changed through high temperature, biomass charcoal is generated in situ, passivation immobilization-microbial strengthening-plant extraction three-stage collaborative operation is carried out according to the time sequence, pollutants are rapidly locked through a passivating agent, rhizosphere immobilization is strengthened through functional microorganisms, plant growth is promoted, and the quality of plants is improved. And the hyperaccumulator finally removes the heavy metals from the soil, so that the unification of short-term control and long-term reduction is realized.

The invention relates to the field of lithium ion batteries, in particular to a biomass carbon / silicon / conducting polymer ternary composite negative electrode material with a hierarchical pore structure and a preparation method and application thereof. According to the material, active nano silicon is effectively limited by utilizing natural graded pore channels of biomass, and a conductive polymer layer with elastic strain buffering capability is prepared by combining a low-temperature in-situ polymerization process. According to the structure, biomass carbon pores are filled with the conductive polymer layer, the specific surface area of the material can be reduced, interface side reaction can be inhibited, and therefore the first coulombic efficiency and cycling stability of the material are improved.

The invention belongs to the technical field of electrode materials, and relates to coffee residue heat treatment doping-based super capacitor carbon and a preparation method and application thereof, coffee residue is used as a raw material, and after hydrothermal carbonization, staged gradient activation and ultrasonic-acid etching coupling treatment, the super capacitor carbon with a rich pore structure is prepared. According to the process, through precise matching of intrinsic characteristics of coffee grounds and process parameters, a hierarchical porous structure is constructed and is matched with an electron transport network formed by self-doping, so that the technical bottleneck that a traditional biomass carbon material is poor in electrical conductivity and difficult to achieve both ion diffusion efficiency is broken through; the super-capacitor carbon with extremely high specific surface area, excellent electricity storage performance and high energy density is finally obtained; a supercapacitor electrode prepared from the supercapacitor carbon has good charge-discharge performance, large specific capacitance, high energy density and good cycle efficiency; moreover, efficient recycling of the coffee grounds can be achieved, the environment-friendly requirement is met, the process is simple, cost is low, and application and popularization are easy.

The invention discloses a biomass carbon loaded manganese dioxide catalyst as well as a preparation method and application thereof. The biomass carbon loaded manganese dioxide catalyst comprises a carrier and MnO2 loaded on the surface of the carrier, and the carrier is carbonized biomass obtained by performing alkali treatment and hydrogen peroxide treatment on biomass and then carbonizing the biomass in an inert atmosphere. The supported catalyst prepared by the method has proper valence and morphology, a MnO2 mixed phase appears, more oxygen vacancies are generated, generation of free radicals in the activation process of peroxymonosulfate (PMS) is facilitated, PMS can be effectively activated to remove organic pollutants, and the activation efficiency of MnO2 on PMS and the operation stability of MnO2 in a packed column are greatly improved. Compared with a traditional method for adjusting the oxygen vacancy of MnO2, the method for loading the biochar is relatively controllable, simple in mode and low in cost.

The invention discloses a low-cost high-first-effect micron silicon negative electrode material and a preparation method and application thereof. The preparation method comprises the following steps: treating the surface of micron silicon by adopting an oxidant solution to form a silicon dioxide passivation layer, and then carrying out surface modification by using a silane coupling agent; the method comprises the following steps: performing acid-base alternate soaking treatment on a biomass carbon source to reduce the content of metal impurities; mixing the delimed biomass carbon source, the composite carbon source and the pretreated micron silicon, firstly adding a weak acid catalyst for hydrothermal reaction to form a hard carbon inner layer, then adding a weak base catalyst for regulating the pH value of the system to alkalescence in batches, and continuing hydrothermal reaction to form a soft carbon outer layer; and washing and drying the product, and carrying out carbonization treatment in an inert atmosphere to obtain the composite coated micron silicon material. The first efficiency of the material is greater than or equal to 92%, the 1C 1000-time circulation capacity retention ratio is greater than or equal to 82%, the raw material cost is low, the process is simple, and the material is suitable for lithium ion batteries in the fields of power, energy storage and consumer electronics.

The present invention discloses a method for preparing a preservative material modified with biomass carbon quantum dots, comprising the following steps: (1) preparing a biomass carbon quantum dot solution; (2) preparing titanium dioxide nanosheets; (3) ultrasonically dispersing the titanium dioxide nanosheets in deionized water and then ultrasonicating, then mixing the titanium dioxide nanosheets with the biomass carbon quantum dot solution and then ultrasonicating, and then performing a high-temperature treatment. The obtained product is subsequently treated to obtain carbon quantum dot-modified titanium dioxide nanosheets with antibacterial and ethylene decomposition functions, i.e., a preservative material modified with biomass carbon quantum dots. The present invention also discloses a preservative material modified with biomass carbon quantum dots prepared by the above method, and the use of the preservative material modified with biomass carbon quantum dots in the preparation of products with antibacterial and photocatalytic ethylene decomposition functions, as well as the use of the preservative material in the preservation of fruits and vegetables.

The invention discloses a preparation method of nitrogen-oxygen co-doped modified biochar and biomass charcoal, and the method comprises the following steps: adding crushed biomass into a carbonate solution, uniformly mixing, drying, grinding into powder, and pyrolyzing in an inert gas atmosphere to obtain first biochar; washing and drying the first biochar, mixing the first biochar with a zeolite imidazole solution containing a metal salt, drying and grinding the mixture, mixing the mixture with melamine, and pyrolyzing the mixture in an inert gas atmosphere to obtain second biochar; the second biochar is washed and dried after being subjected to acid pickling, and the modified carbon nanotube biochar is obtained. Therefore, melamine pyrolysis gas is catalyzed to grow the carbon nanotubes on the carbon material, so that the charge transfer resistance of the carbon material is reduced, the electrochemical performance of the carbon material is improved, the resistance of modified biochar can be remarkably reduced, the conductivity of the biochar can be improved, and the electrochemical performance of porous carbon is improved.

The invention relates to a chromium-targeted adsorbing material as well as a preparation method and application thereof. The preparation method of the targeted chromium adsorption material comprises the following steps: S1, crushing, sieving and pyrolyzing stems of potassium-rich plants to obtain biomass carbon; s2, dispersing biomass carbon in a solvent, adding Cr < 6 + > template ions, Cr < 3 + > template ions, a functional monomer, a cross-linking agent and an initiator for reaction, and washing and drying after reaction to obtain an ion imprinted polymer; and S3, dissolving a reduction barrier agent in a solvent, adding the ion imprinted polymer, and reacting at room temperature to obtain the chromium-targeted adsorption material, the potassium-rich plants are plants with the total potassium mass content of 5%-8%. The long-acting reduction adsorption material for targeted remediation of heavy metal Cr < 6 + > / Cr < 3 + > polluted soil and underground water is prepared, has extremely high specific selectivity and efficient adsorbability, and has obvious advantages in the aspects of heavy metal treatment efficiency, continuity and acid interference resistance.

The invention relates to the technical field of batteries, in particular to a negative electrode material, a preparation method thereof, a negative electrode plate and a battery. The preparation method comprises the following steps: mixing a biomass raw material with an oxidizing agent, and carrying out oxidation reaction to obtain oxidized biomass; mixing the oxidized biomass and a modifier in a solvent to obtain a mixed solution of the oxidized biomass and the modifier, and performing modification reaction to obtain modified oxidized biomass; carrying out hydrothermal reaction treatment on the modified oxidized biomass to obtain a biomass carbon precursor; carrying out carbonization treatment on the biomass carbon precursor to obtain a negative electrode material; wherein the modifying agent is prepared from p-aminoazobenzene. The negative electrode material prepared by the preparation method has relatively large interlayer spacing and outstanding structural stability, and shows high sodium storage capacity and excellent cycling stability in the aspect of electrochemical performance.

The invention discloses a porous carbon material preparation method based on a fluidized bed steam step-by-step activation method, and belongs to the field of porous carbon material preparation, the method comprises the following steps: carbonizing a biomass carbon-based raw material to prepare first carbonized particles; the first carbonized particles are subjected to acid pickling, and second carbonized particles with the ash content being smaller than 0.3% and the pH value being 6-8 are obtained; placing the second carbonized particles in a fluidized bed reactor, and carrying out first activation treatment; and stopping heating after the first activation treatment is completed, keeping the temperature when the temperature of the fluidized bed reactor is reduced to 850 DEG C, carrying out second activation treatment, and cooling to room temperature after the second activation treatment is completed. The method is simple in process operation, green and environment-friendly, and has a wide large-scale production prospect.

The invention belongs to the technical field of biomass and solid waste resource utilization, and particularly relates to a biomass activated waste rubber powder material and a preparation method and application thereof. Biomass, acetic acid and water are mixed, a reaction mixture is obtained through a hydrothermal reaction and acetone flushing, a moisture-containing biochar solid and a bio-oil-containing liquid are obtained through vacuum filtration, the moisture-containing biochar solid is dried to obtain biochar, a part of biochar is selected to be ground and dialyzed to obtain biomass carbon dots, and the biomass carbon dots are prepared into biomass carbon dots. Drying the liquid containing the bio-oil to obtain the bio-oil; mixing the obtained bio-oil, biochar, biomass carbon dots and waste rubber powder, and performing microwave activation to obtain biomass activated waste rubber powder. The regenerated asphalt can be obtained by doping the biomass activated waste rubber powder into the waste asphalt. The method provided by the invention can greatly reduce the stockpiling amount of biomass, waste tires and waste asphalt mixtures, improve the ecological environment of the expressway and reduce carbon emission, and has important significance for popularization and application of multi-source solid wastes in highway engineering.

The invention belongs to the technical field of methyl red azo dye purification, and discloses a methyl red azo dye adsorbent with good adsorption performance on a methyl red azo dye adsorbent, and a preparation method and application thereof. The preparation method comprises the following steps: (1) preparing a first precursor solution and a second precursor solution; the first precursor solution contains melamine, and the second precursor solution contains cyanuric acid and / or barbituric acid; (2) sequentially adding the first precursor solution and the second precursor solution into biomass carbon powder to form a reaction solution; enabling the supermolecule aggregate to grow in situ and coat the surface of the biomass carbon powder under a stirring condition to form a solid-liquid mixture; removing the solvent in the solid-liquid mixture, and drying to obtain a supramolecular composite precursor; (3) carrying out pressure molding on a mixture of the supramolecular composite precursor, silicate clay mineral and nickel salt to obtain a green body; and (4) carrying out heat treatment on the green body to obtain the methyl red azo dye adsorbent.

The invention discloses a biomass carbon composite wave-absorbing material and a preparation method thereof, the material is formed by gathering Fe and Fe3C particles on the surface of biomass carbon, and the surface of the biomass carbon has a porous structure; after adsorbing the ferric salt, the biomass is calcined to generate biomass charcoal, and Fe and Fe3C particles are generated on the surface of the biomass charcoal; the preparation method comprises the following steps: (1) immersing dry biomass into an alkaline solution for pretreatment; (2) immersing the pretreated biomass into a ferric salt solution for adsorption; and (3) calcining the biomass adsorbed with the ferric salt under the protection of inert gas, and generating Fe and Fe3C on the surface of the biomass charcoal. According to the invention, a porous structure is constructed on the surface of biomass through pretreatment, and Fe and Fe3C are introduced on the surface of biomass carbon, so that the wave-absorbing electromagnetic shielding and stability of the material are improved.

The invention relates to the technical field of functional materials, and discloses a preparation method of a nitrogen-doped biomass carbon material based on coffee grounds and application of the nitrogen-doped biomass carbon material in a lithium ion battery negative electrode material. Coffee grounds are used as a carbon source, melamine is used as a nitrogen source and an additive, and potassium hydroxide is used as an activating agent. The preparation process comprises the following steps: mixing coffee grounds with melamine, carrying out heat treatment to generate pre-carbon, and carrying out secondary carbonization after mixing with potassium hydroxide. According to the method, the conductivity and the specific surface area of the material are enhanced through nitrogen doping, and the charge-discharge capacity and the cycle stability of the lithium ion battery are improved. The preparation method is simple in preparation process and suitable for large-scale industrial production, and a new way is provided for high-value utilization of the waste coffee grounds and preparation of high-performance battery materials.

The invention provides a pretreated biomass charcoal loaded vulcanized nano zero-valent iron material as well as a preparation method and application thereof, and relates to the technical field of environmental functional materials. The preparation method comprises the following steps: firstly, dipping pretreated biomass in phosphoric acid, pyrolyzing, and then ball-milling and crushing to micro-nano scale; then, FeCl3 is used as a precursor, NaBH4 and Na2S2O4 are used as a reducing-vulcanizing agent, and S-nZVI is loaded through a one-step method. The composite modified material has high efficiency in heavy metal pollution in a water body, can simultaneously remove various pollutants, has a wide application prospect, and provides a new efficient material choice for the field of environmental restoration.

The invention provides fluorescent carbon dots and fluorescent hydrogel based on solvent stimulation response discoloration and a preparation method and application of the fluorescent carbon dots and the fluorescent hydrogel, and belongs to the technical field of fluorescent materials and information encryption. The preparation method of the fluorescent carbon dots comprises the following steps: mixing a biomass carbon source and a solvent, and performing solvothermal reaction to obtain the fluorescent carbon dots, the biomass carbon source comprises one or more of buxus buxus, oriental cherry leaves, fructus forsythiae leaves and oak leaves; the solvent is ethanol. The biomass carbon dots are low in toxicity, excellent in optical stability and photobleaching resistance and high in ionic strength; the fluorescent carbon dots have double emission peaks of red light and blue light / green light, are different from single fluorescent carbon dots, and can provide more fluorescent information storage density for a fluorescent gel-based information orientation encryption system. The fluorescent color of the fluorescent hydrogel can be stably switched in an ethanol / water solvent, the gel structure is stable, the information storage capacity is improved, and a fluorescent hydrogel-based information anti-counterfeiting encryption system is promoted to develop towards multiple dimensions.

The invention belongs to the technical field of hydrogel, and discloses polyvinyl alcohol hydrogel and a preparation method thereof.The preparation method comprises the steps that polyvinyl alcohol, a biomass carbon quantum dot solution, a plasticizer and a first cross-linking agent are mixed, heated and dissolved to form a homogeneous solution; defoaming the homogeneous solution, injecting the solution into a mold, and performing freeze-thaw cycle treatment to form primary hydrogel; immersing the primary hydrogel into a solution containing a second cross-linking agent for secondary cross-linking to obtain composite polyvinyl alcohol hydrogel; wherein the biomass carbon quantum dot solution is prepared from a biomass raw material through a hydrothermal reaction. The self-healing and conductive hydrogel prepared by the method has the advantages of cheap and easily available raw materials, simple equipment operation, green and environment-friendly technological process, good product biocompatibility and the like, and is suitable for industrial production.

The invention relates to a system and a process for preparing an efficient carbon-based fertilizer by carbonizing agricultural and forestry biomass, which are applied to the technical field of carbon-based fertilizer preparation, and the system comprises a raw material pretreatment unit, a biomass granulation unit, a biomass carbonization unit, a biomass charcoal activation unit, a finished product post-treatment unit and a volatilization inhibition composite unit, the volatilization-inhibiting composite unit comprises a mixed base preparation module and a wrapping volatilization-inhibiting module; the wrapping volatilization-inhibiting module comprises a rotary drum granulator, a base material feeder, a nitrogen source feeder, a humidity adjusting mechanism and a granulation control module; based on the design of the volatilization-inhibiting composite unit, a graded volatilization-preventing granulation strategy of firstly preparing a nitrogen-free core and then wrapping a nitrogen fertilizer is adopted, so that direct and large-area contact between high-pH-value biochar and volatile nitrogen source components in the granulation process is thoroughly isolated from physical space and time sequence; therefore, generation and dissipation of a large amount of ammonia gas are avoided from the source, and the utilization efficiency of the fertilizer is remarkably improved.