1327results about How to "Extensive sources of raw materials" patented technology

The invention discloses preparation of a super-hydrophobic ice-covering-proof coating having a slowly-releasing function. The ice-covering-proof coating consists of the following substances in parts by mass: 1.5-5 parts of inorganic hollow or porous nanoparticles for adsorbing small molecular anti-icing substances, 2-5 parts of fluorine-containing polymer and 1-15 parts of solvent. The super-hydrophobic ice-covering-proof coating having the slowly-releasing function can be obtained by uniformly mixing the three substances and coating the mixture onto the surface of a substrate. At the normal temperature, the water contact angle of the coating is greater than 150 degrees, and the rolling angle is smaller than 7 degrees. At 10 DEG C below zero, the low-temperature contact angle of water is greater than 140 degrees, and the rolling angle is smaller than 12 degrees. During testing of the ice cover at 10 DEG C below zero, the ice cover is lowered by over 70 percent, and is still higher than 50 percent after testing is performed circularly for ten times in comparison to a blank sample.

The invention discloses a graphene filled polymer matrix composite material. The composite material is prepared through using 90-99 parts by weight of a thermoplastic resin, 0.1-10 parts by weight of a graphene microchip, 0.01-1 part of a coupling agent, and 1-10 parts of a lubricant. The invention also discloses a preparation method of the graphene filled polymer matrix composite material. Compared with other carbon system filled composite materials, the graphene filled polymer matrix composite material has the advantages of easy processing, easy forming, less filler filling amount, wide raw material source, environmental protection and the like. The composite material has the characteristics of excellent electric conductivity, excellent thermal conductivity, good mechanical properties, good dimensional stability, good weather resistance and the like; and compared with present technologies for preparing a graphene / polymer composite material through in-situ polymerization or solution polymerization, the melt blending method for preparing the graphene filled polymer matrix composite material in the invention has the advantages of continuous production, suitableness for the large-scale production, and the like.

The invention relates to high-strength ultra-high-toughness concrete and a preparation method thereof. The concrete is prepared from, by weight, 400-800 parts of cement, 100-250 parts of silica fume, 200-500 parts of slag powder, 200-500 parts of fly ash, 200-500 parts of quartz powder, 800-1,000 parts of quartz sand, 20-40 parts of a water reducing agent, 180-250 parts of water and 15-25 parts of polyethylene fibers. When the concrete is prepared, the cement, the silica fume, the slag powder, the fly ash, the quartz powder and the quartz sand are added into a stirrer by weight, and the dry powder is stirred for 2-3 min and fully mixed to be uniform; after stirring is finished, the mixed dry powder is transferred into a mold, vibrating is conducted for 1-2 min for molding, curing and demolding are conducted, and then the high-strength ultra-high-toughness concrete is prepared. Compared with the prior art, the concrete has the advantages that the compressive strength reaches 120-150 MPa, the breaking strength reaches 30-50 MPa, the tensile strength reaches 15-22 MPa, and the tensile elongation reaches 4%-8% and has the very good application prospect.

The invention discloses a Chinese medicinal herb additive for egg chickens and application. The Chinese medicinal herb additive comprises membranous milkvetch root, eucommia bark, honeysuckle, jiuyue, Weeping Forsythiae Capsule, szechwon tangshen root, sanguisorba, hawthorn, Indian Buead, officinal magnolia bark, Chinese pulsatilla root, giant knotweed rhizome, ricepaperplant pith, largehead atractylodes rhizome, tangerine peel, malt, indigowoad root, swordlike atractylodes rhizome, indigowoad leaf, three immortals, liquorice, cyrtomium fortune, nutgrass galingale rhizome, chatoyancy, calamus and pinellia tuber, and mixture of the compositions is added with calcium bicarbonate, phytase, vitamin E and methionine. The Chinese medicinal herb additive effectively promotes absorption of nutrient, can prevent and control diseases, strengthen quality of eggshells, reduce the broken egg rate and soft-shell eggs, abnormal eggs and sand shell eggs, can effectively prevent bird flu, prevent and control diseases such as laxness, feather pecking, hair shedding, anus pecking, salpingitis, respiratory disease and the like, can achieve good effect with a dosage of about 4 percent, cannot damage physiological functions of the egg chickens, and can prolong egg laying peak season, improve color of the eggshells and the laying rate by 8 to 20 percent, and increase weight of eggs.

The invention relates to a membrane adsorbent for removing heavy metal ions and a preparation method thereof, in particular to a method for preparing a membrane adsorbent for removing heavy metal ions from water by utilizing the process of membrane filtration. Casting membrane liquid for preparing the membrane adsorbent comprises the following components in percentage by mass: 70 / 30 to 20 / 80 percent of polymer / resin, 4 to 30 percent of additive and 30 to 75 percent of solvent, wherein the concentration sum of the polymer and the resin is between 20 and 55 percent, and the sum of components is 100 percent. According to the formula of the invention, the method of the membrane adsorbent comprises the following steps of: 1, preparing the casting membrane liquid; 2, preparing a membrane; and 3, performing aftertreatment. The surface of the membrane adsorbent has an opening structure, so the membrane adsorbent has the excellent adsorption function, can be used as filtering and adsorbing media, and is particularly suitable for removing the heavy metal ions from the water.

The invention relates to the battery field, and in particular relates to a silicon-carbon composite material and a preparation method thereof and application thereof in lithium ion battery. The following problems exist in the application of silicon-based materials in the lithium ion battery: 1. first coulombic efficiency of the lithium ion battery is low; 2, cycle life of the lithium ion battery is short; 3, the rate performance is poor; 4, the materials are low in production efficiency, and not conducive to large-scale industrial production. In order to solve the problems, the silicon-carbon composite material is provided, secondary-particles comprise a plurality of first particles containing core-shell structures, the core-shell structure comprises a carbon shell layer and silicon core particles which are completely wrapped by the carbon shell layer, and a gap is between the carbon shell layer and the silicon core particles. The preparation method of the silicon-carbon composite material and the application of the silicon-carbon composite material in the lithium ion battery are also provided.

The invention relates to a preparation method for carbon microspheres with high specific surface area. The preparation method includes the following steps: a carbon material, an alkaline activator, a binder and a solvent are mixed and stirred to obtain slurry, or the alkaline activator, the binder and the solvent are mixed and stirred to obtain slurry; all the materials are granulated to obtain primary carbon microspheres; the primary carbon microspheres go through activation, pickling, washing and drying to obtain the carbon microspheres with the high specific surface area. The preparation method provided by the invention adopts low-value carbonaceous waste materials or amorphous carbonaceous raw powders to prepare the microsphere carbon material with the high specific surface area, so as to meet the use requirements of multiple fields; the preparation technique is simple, the operation is convenient, and large-scale production is facilitated; the prepared carbon microspheres with the high specific surface area have an excellent spherical structure, a high degree of sphericity and a controllable particle size, and barely contain metal impurities.

The invention discloses a method for reducing pollution caused by heavy metals including arsenic, lead, cadmium and mercury in paddy rice. The method comprises the following steps of: (1) spraying a bivalent manganese fertilizer in the amount of 2-30 grams per mu at the initial booting stage of paddy rice, and irrigating into a paddy field within 2-3 days; and (2) spraying a selenium fertilizer in the amount of 1-5 grams per mu at the full heading stage of the paddy rice. Due to the adoption of the method, the content of heavy metals in the paddy rice can be lowered, and the yield as well as the content of trace mineral nutritional elements in rice can be increased.

The invention relates to a medical hydrogel dressings and a preparation method thereof. The hydrogel dressings is prepared by taking 10-30% by mass of starch and 2-15% by mass of water-soluble polymer as raw materials, utilizing a guanidinesalt polycondensate as an anti-bacterial agent, adding a cross-linking agent, and reacting at the temperature of 40-80 DEG C. The operation steps are as follows: adding the starch and the water-soluble polymer in a solvent to prepare into a solution, regulating the pH value of the solution by a NaOH solution, heating for gelatinization, cooling, adding the anti-bacterial agent and the cross-linking agent, stirring to form a mixed solution, pouring the mixed solution into a die, and reacting at the temperature of 40-80 DEG C to obtain the anti-bacterial hydrogel. Compared with the prior art, the hydrogel dressings in the invention has the advantages of good swelling property, high transparency, moderate mechanic strength, excellent bacteria invasion resistance, wide raw material sources, cheap raw materials, good tissue compatibility and favorable medical application prospect, and can effectively prevent wound infection.

The invention discloses a Chinese medicinal herb additive for promoting the growth of a piglet and the application thereof; wherein the additive comprises the following components: officinal magnolia bark, bitter orange, Chinese pulsatilla root, medicated leaven, rhizoma discoreae, sepium, dangshen, polygonummultiflorum thunb, hawthorn, rhizoma atractylodis, dried orange peel, milk veteh, malt, the rhizome of large-headed atractylodes, and wild jujube. According to the physiological function of the piglet, all components with the pertinence are compatible with each other, make good for deficiency, are cooperated with each other and mixed in a matching way. Proved by experiments, the additive has the functions of invigorating the stomach, helping digestion, promoting blood circulation, removing blood stasis, calming the nerves, tranquilizing, and increasing immunity, can prevent disease, treat an illness, help the growth, increase the disease resistance of the piglet, does not have any side effect and harmful substance to be remained; only about 20% of dosage of the additive can play greater function; the additive does not harm the digestive system of the piglet and other physiological functions and is beneficial for the growth of the piglet and the strengthen of disease-resistance capability.

A gamma-AlOOH nanocrystal powder able to be automatically dispersed in aqueous and some organic solvents for preparing self-dispersing superfine non-toxic aluminum hydroxide flame-retarding agent, or the high-molecular polymer / inorganic nano-material composition, or the microcrystalline alumina ceramics or high-performance alumina ceramics as grinding medium is prepared through reaction of sodium aluminate or Al salt solution in alkaline medium, extracting the generated deposit, adding peptizing agent and disperser, peptizing and dispersing to obtain aluminum hydroxide colloid, reacting on additive and surfactant for surface modifying, and spray drying.

The invention relates to a hydrothermal synthesis method for preparing iron phosphate lithium as an anode material of lithium ion battery, which belongs to the technical field of new energy materials. The hydrothermal synthesis method comprises the following steps of: mixing an iron source with phosphate, adding a lithium source, and after uniform agitation, putting the mixture into a high-pressure reaction kettle; then, adding a reducing agent, and maintaining the temperature at 180-200 DEG C for 8-12 h to produce spherical iron phosphate lithium, wherein the mol ratio of the lithium source to the iron source to the phosphate is 3:1:1. The invention provides a simple and one-step method for directly preparing iron phosphate lithium. The technological parameters of the method used for preparation are easily controlled; compared with a process using ferric iron as a raw material, the resource of ferrous iron as the raw material is wider; the prepared iron phosphate lithium powder particles have small mean particle diameter which is about 3-5 mu m, the particles are evenly distributed, the tap density can reach 2.0-2.5 g / cm<3>, the battery performance is high, and the specific capacity for the first charge and discharge cycle is 140-160 mAh / g.

The invention discloses a lignin-based transition metal / nitrogen doped carbon material, and preparation and application thereof, belonging to the technical field of carbon materials. A preparation method comprises the following steps: (1) uniformly mixing a transition metal salt with lignin in water to obtain a lignin / transition metal salt mixed liquid; (2) subjecting the lignin / transition metal salt mixed liquid to hydrothermal pre-carbonization so as to obtain a hydrothermal pre-carbonization product; and (3) mixing the hydrothermal pre-carbonization product with a nitrogen source, carryingout high-temperature carbonization in a protective atmosphere, and carrying out subsequent treatment so as to obtain the lignin-based transition metal / nitrogen doped carbon material. The lignin-basedtransition metal / nitrogen doped carbon material of the invention has excellent electrochemical performance; and the preparation process of the material is simple, raw materials are widely available and cheap, and an effective way is provided for the high-value utilization of biomass. The carbon material of the invention is applied to fields of fuel cells, supercapacitors, adsorbent materials, and / or water electrolysis.

The invention provides a preparation method for graphene reinforced polymer porous sponge fiber. The preparation method is characterized in that: the graphene reinforced polymer porous sponge fiber is prepared by subjecting an oxidized graphene solution having a certain concentration to ultrasonic processing to obtain a uniformly dispersed oxidized graphene solution; dissolving a polymer in a solvent to obtain a polymer solution with a certain concentration; adding the dispersed graphene solution into the polymer solution under stirring to obtain a graphene-polymer blend spinning solution; spraying the graphene-polymer blend spinning solution through a spinning nozzle into a coagulating bath to form fiber by utilization of a wet-method spinning device; washing with water, reducing, and washing with water again; and quickly subjecting the wet fiber to freeze drying or supercritical drying to obtain the graphene reinforced polymer porous sponge fiber. The preparation method is simple in technology and low in cost, and is suitable for large-scale production. The fiber has advantages of high strength, good antistatic performance, good elasticity, small density, large specific surface area, and the like. The fiber can be used for preparing heat insulating fabrics in the weaving field, and can be used for water treatment in the environment protection field, and the like.

The invention discloses a Chinese medicinal herb additive for meat chickens and application. The Chinese medicinal herb additive comprises heterophylly falsestarwort root, nutgrass galingale rhizome, amur corktree bark, coptis root, medicated leaven, sanguisorba, hawthorn, Indian Buead, officinal magnolia bark, largehead atractylodes rhizome, tangerine peel, malt, indigowoad root, swordlike atractylodes rhizome, indigowoad leaf, cyrtomium fortune, chatoyancy and calamus; and mixture of the compositions is added with calcium bicarbonate, phytase, mulitivitamin for birds and lysine. The Chinese medicinal herb additive effectively promotes absorption of nutrient, can resist bacteria and virus, strengthen immunity of the meat chickens, effectively prevents bird flu, has obvious curative effect on diseases having respiratory tract symptoms as the major symptom, and has inhibiting function on familiar newcastle disease, colon bacillus, Pasteurella, enteritis, diarrhea, feather pecking, hair shedding, anus pecking, coccidiosis and the like. The additive cannot restrict the growth and disease resistance of the meat chickens, the meat quality of the meat chickens fed by the additive is obviously better than that of the meat chickens fed by the prior feed additive, the average daily gain of the meat chickens is improved by 23 to 28 percent than that of the meat chickens fed by the prior feed additive, the cultivation cycle is obviously shortened, and no harmful substance is deposited.

The invention discloses a preparation method of diatomite-based porous ceramic microspheres. According to the invention, diatomite is adopted as a main material, and the ceramic microspheres with high sphericity (good fluidity), large specific area, and controllable particle sizes are prepared through spray-drying. The diatomite-based porous ceramic microspheres can be used as catalyst carriers in slurry-bed reactions such as Fischer-Tropsch synthesis. The method provided by the invention is advantaged in wide material source, simple technological process, low production cost, and suitabilityfor large-scale continuous industrialized productions. The method has good application values.

The invention relates to a rock soil similar material and a preparation method thereof, and the rock soil similar material is particularly suitable for a geotechnical engineering geomechanics model test and a seismic modeling vibrating table physical model test. According to the rock soil similar material, powdered iron and barite powder are selected as fine aggregates, quartz sand is selected as a coarse aggregate, gypsum is selected as a cementing agent, and glycerin is selected as a conditioning agent. The preparation method comprises the following steps of: weighing and uniformly stirring all the components of the rock soil similar material according to the mass part; pouring the stirred mixture in a rigid mould and compacting the mixture by layers; and after the mould is removed, naturally airing a test piece which is taken down at a normal temperature for 5-7 days. The rock soil similar material has the advantages of high density, large strength and deformation parameter change range, wide raw material source, simple preparation method, stable mechanical property at the room temperature, no harm to a human body, and the like; and the test piece is easily processed and formed, and is naturally aired without curing.

The utility model discloses an improved soda lime sintering method for processing aluminum-containing raw material, and relates to the technical field of aluminum oxide production with a sintering method. The aluminum-containing raw material, limestone and soda ash are evenly mixed in a ball-milling manner according to a raw meal formula of the improved soda lime sintering method, thereby acquiring qualified raw meal; the raw meal is sintered at a high temperature, thereby acquiring sintered clinker; the sintered clinker is dissolved out, desiliconized, resolved and roasted; and an aluminum oxide product can be finally acquired. The raw meal formula of the improved soda lime sintering method is that the sum of the amount of Al2O3, the amount of Fe2O3 and the amount of SiO2 divided by the sum of the amount of Na2O and the amount of K2O is equal to 1.0 plus or minus 0.1 (a molar ratio), and the sum of the amount of SiO2 and the amount of TiO2 divided by CaO is equal to 1.0 plus or minus0.1 (the molar ratio). Compared with the prior art, the improved soda lime sintering method disclosed by the invention has great adaptability to aluminum-containing raw material in various grades, and has the advantages that the addition quantity of burdening lime stone is small, the resource utilization efficiency is high, the sintering temperature is low, the firing energy consumption is low, the firing temperature range is wide, and the industrialization is easy to implement.

The invention relates to a two-stage gasification method and a gasification device for a fuel with wide size distribution. The two-stage gasification method for the fuel with wide size distribution comprises the steps of 1) adding the fuel to a fluidized bed pyrolyzer by a feeding device; adding a gasifying agent to the fluidized bed pyrolyzer; drying / pyrolyzing or partly gasifying the fuel under semicoking of the pyrolyzer and heating of the gasifying agent; and 2) sending the solid and gas generated in the step 1) to a fluidized bed gasification furnace, adding the gasifying agent to the fluidized bed gasification furnace, finishing complete gasification of semicoke; removing tar by high-temperature pyrolysis, part oxidization and semicoke catalytic reforming in the fluidized bed so as to produce clean gas. With the adoption of the method, the traditional fuel gasification process is divided into a material pyrolysis stage and a semicoke gasification stage, which are performed in an upper fluidized bed pyrolyzer and a lower fluidized bed gasification furnace.

The invention discloses a surface modified porous carbon structural carbon fiber / sulfur composite cathode material and a preparation method thereof. The composite cathode material is formed by compounding surface modified porous carbon structural carbon fiber and elemental sulfur. The preparation method comprises the steps: firstly, preparing an organic metal frame coated carbon fiber composite by using a solvothermal method; carbonizing the composite at high temperature; and then, compounding the composite with sulfur to obtain the surface modified porous carbon structural carbon fiber / sulfur composite cathode material. The preparation method is simple; the adopted raw materials are low in cost; the prepared composite cathode material has high specific capacity and high utilization ratio of active sulfur; the cycle performance of a lithium sulfur battery is greatly improved.

The present invention discloses antistatic reinforced polyphenyl thioether composite material and its preparation process. The composite material consists of polyphenyl thioether 30-80 weight portions, glass fiber 20-60 weight portions, inorganic mineral filler 0-40 weight portions, hydrophilic polymer 3-10 weight portions, alkali metal salt 0.2-3 weight portions, interface modifier 2-10 weight portions, coupling agent 0.1-2 weight portions, antioxidant 0.1-1 weight portion, and processing aid 0.1-1 weight portion. The antistatic reinforced polyphenyl thioether composite material has excellent mechanism performance, excellent antistatic performance and high durability, and may be used in coal mine machine, business machine, fixed disk driver, etc.

The present invention discloses a method of producing yeast protein feed with leftovers from kitchen. The production process of high-calcium multivitamin yeast protein feed includes crushing, dewatering, adding nitrogen to neutralize, disinfection, inoculation of yeast and microbial bacteria, solid fermentation under control of computer, drying, milling, assaying and packing. It makes it possible to change waste leftovers into high-quality high-calcium multivatamin yeast protein feed.

The invention discloses a method for preparing organic montmorillonite by using solid phase modified Ca-montmorillonite, specifically, the Ca-montmorillonite and a modifier or a mixed modifier are stirred for reaction at high temperature and modified to obtain the organic montmorillonite in solid phase powered state. The obtained organic montmorillonite can be directly applied to a plurality of polymer materials and can realize the intercalation of rubber macromolecule chains in mixing and vulcanizing process. Verified by mechanical property, properties of the obtained composite material, such as tensile strength, modulus, elongation at break and the like, are boosted and excellent. The method has the advantages of wide source of raw materials, handiness and feasibility, low production cost, no need of water or solvent and no environment pollution, with wide industrial application prospect.

The invention discloses a method for preparing a nitrogen-doped modified porous carbon with high specific surface area. The method comprises the following steps: drying and crushing biomass raw materials to obtain granules, and performing high-temperature ammoniation on the granules under an ammonia atmosphere to obtain a nitrogen-containing carbide; then dispersing the nitrogen-containing carbide into an activating agent solution, stirring and drying to obtain an activating agent / carbon mixture; and performing high-temperature activation on the activating agent / carbon mixture under a nitrogen atmosphere, washing, filtering, drying, thus obtaining the nitrogen-doped modified porous carbon material with a high specific surface area. The specific surface area of the prepared carbon material is 2,000-3,500m<2> / g, the pore size of the material is 0.4-8nm, and the nitrogen content is 0.5-5%. The method is simple, effective and easy to operate, facilitates large-scale batch production, and is applicable to industrial production.

The invention relates to a polymer dispersed liquid crystal (PDLC) material which is low in voltage and wide in temperature mode, wherein the material consists of a liquid crystal material, an aliphatic polyurethane acrylate oligomer, an acrylate monomer, a photoinitiator and interstitials. The invention further provides a polymer dispersed liquid crystal display apparatus prepared by using the polymer dispersed liquid crystal material and a preparation method thereof. The polymer dispersed liquid crystal material provided by the invention has the advantages of wide raw material source and simple and convenient preparation process. The PDLC display apparatus prepared from the PDLC material has the advantages of low driving voltage, wide range of working temperature, no shrinkage and deformation and good adhesive force. The preparation method of the PDLC display apparatus is simple and convenient, the thickness of the display apparatus can be adjusted according to size of the interstitials added, and the display apparatus obtained is good in adhesive force and not easy to shrink and deform, so that the PDLC display apparatus with a large area can be probably prepared.

The invention discloses a humic acid composite slow-release fertilizer and a method for preparing the same. In the fertilizer, weathered coal and the common fertilizer are used as raw materials, and subjected to activation of the weathered coal, material mixing, high-temperature spraying granulation and drying to obtain the fertilizer. By the organic-inorganic combination, the organic-inorganic mutual-aid control and the nutrient slow release, the fertilizer improves the utilization rate of the fertilizer (10 to 15 percent), reduces loss of nutrients and avoids the secondary pollution. The fertilizer has the characteristics of wide material source, high mechanical strength of fertilizer particle (the mechanical strength is more than and equal to 16N), no deliquescence, convenient transportation and use and the like, and has wide application prospect in production.

The invention discloses a preparation method of cationic surfactant modified fly ash, which comprises the following steps of: firstly performing pretreatment and hydroxylation treatment on the surface of fly ash to obtain hydroxylated fly ash to obtain a grafting point; then modifying the fly ash by use of a coupling agent; and finally performing grafting reaction with a cationic surfactant polyacrylamide to obtain cationic surfactant modified fly ash. According to the preparation method disclosed by the invention, the polyacrylamide is grafted on the surface of the fly ash, and the adsorption property of the grafted fly ash is greatly changed; particularly the fly ash is applied to a cement-based composite material, and the fracture resistance of the cement-based composite material is obviously improved; and the preparation method disclosed by the invention has the advantages of low reaction temperature, mild conditions, simple after-treatment and low industrialization cost.

The invention relates to a hollow silicon-carbon composite material and a preparation method thereof. According to the hollow silicon-carbon composite material, the silicon-carbon composite material is spherical or ellipsoid secondary particles; the secondary particles have hollow structures, the shell is formed by compounding graphite sheets, a silicon material and amorphous carbon, the silicon material is uniformly adhered on the surface of the graphite sheet and between the graphite sheets, and the surfaces of all the graphite sheets and the silicon material are covered with an amorphous carbon protection layer; and the graphite sheets for forming the secondary particles are randomly oriented to each other. According to the present invention, the silicon-carbon composite material used as the lithium-ion battery negative electrode has electrochemical characteristics of high capacity, high Coulomb efficiency, low expansion and good cycle performance; the lithium-ion battery prepared from the silicon-carbon composite material has characteristics of high volume energy density, low expansion and good cycle performance; and the preparation process has advantages of simpleness, wide raw material source and low cost, and can achieve the industrial application of the silicon-carbon composite material in the lithium battery field.

The invention relates to a multifunctional nano composite material of a core-shell structure and in particular relates to a carbon quantum dot magnetic fluorescent difunctional nano material and a preparation method thereof. Magnetic particle Fe3O is taken as a core, chitosan and polyanionic-based cellulose are taken as shell material, a carbon quantum dot is taken as a fluorescent material, and the carbon quantum dot magnetic fluorescent difunctional nano material is obtained by adopting a layer-by-layer self-assembly method; the carbon quantum dot is coated by adopting a natural polymer material, so that no free carbon quantum dot is formed, and stability is improved; magnetic property and fluorescence strength can be regulated and controlled by virtue of number of layers of the shell material and the addition amount of the carbon quantum dot; the obtained magnetic fluorescent difunctional nano material has a broad application prospect in the biological medicine fields of cell marking and absorption, bioimaging, medicine detection and disease diagnosis, medicine carrying and the like.

The invention relates to a preparation method of a petroleum asphalt-based carbon quantum dot. The preparation method comprises the following steps: (1) adding concentrated nitric acid and concentrated sulfuric acid into petroleum asphalt and carrying out ultrasonic treatment to obtain a dispersion liquid of the petroleum asphalt; (2) heating the dispersion liquid of the petroleum asphalt obtained in the step (1) in an oil bath to reflux, cooling to room temperature, regulating to neutral by using alkali and distilled water to obtain a coarse product; and (3) separating and refining the coarse product obtained in the step (2) to obtain the petroleum asphalt-based carbon quantum dot. According to the preparation method provided by the invention, the carbon quantum dot is prepared by taking common petroleum asphalt as a carbon source. The petroleum asphalt is rich in polycyclic aromatic rings and has graphene-like condensed ring structures. After chemical oxidization, besides oxygen-containing functional groups at the edge, a petroleum asphalt nanosheet further has carbine-like zigzag structure and carbine-like armchairs structures.