103results about How to "Size is easy to control" patented technology

The invention discloses a silver nanodendrite surface enhanced Raman scattering (SERS) substrate, and a preparation method and application thereof, relating to the technical field of nanomaterial science and Raman detection. The SERS active substrate is of silver dendrites which are distributed evenly, and the three-dimensional sizes of dendrites are adjustable. The preparation method of the invention is characterized in that the silver nanodendrites are electrically deposited on commercially available ITO (Indium-doped Tin Oxide) conductive glass by adopting a constant current deposition method and using a silver nitrate solution as electrolyte without adding any other auxiliary. The preparation method of the invention has the advantages of simple, convenient fast (30s) preparation process, low cost, small current and low voltage, and the silver dendrites can be transferred to any substrate (paper, other metal sheets or plastic sheets). The substrate obtained by the method disclosed by the invention has high stability and ordered and controllable structure, and exhibits quite high sensitivity in Raman spectrum detection.

An antibacterial composition for paint, ceramics, rubber, plastics, etc. is composed of microporous or mesoporous SiO2 particles as carrier and silver phosphate and / or TiO2 as active components which are compounded on the surface of the said SiO2 particle. Its advantages are high antibacterial effect, high hydrophilicity and low cost.

The invention relates to a composite magnetic powder core and a preparation method of the composite magnetic powder core. According to the technical scheme, nanometer ferrite particles with even size are prepared on the surface of soft magnetic alloy powder through a hydrothermal method in a root-positioning mode, and a novel ferrite composite magnetic powder core is prepared through the pressing and thermal processing technology. The composite magnetic powder core and the manufacturing method of the composite magnetic powder core have the advantages that due to the fact that manganese zinc ferrite and nickel zinc ferrite are prepared through a hydrothermal method and a root position method, nanometer particles with controllable and even size can be prepared conveniently; the ferrite can be used as an insulated coating agent of the soft magnetic alloy powder, the defect that magnetic performance of a substrate is reduced when traditional nonmagnetic substances are used as the coating agent are overcome, and high magnetic conductivity and saturation magnetization strength can be obtained.

The invention relates to a preparation method of pegylation modified hyperbranched poly(ethylene imine) (PEI) coated nano-gold particles, which comprises the following steps: modifying PEI by using mPEG (polyethylene glycol)-COOH, and sequentially carrying out dialysis and freeze-drying on the obtained product so as to obtain PEI-mPEG; taking the solid, dissolving the solid by using water, adding a HAuCl4 solution into the dissolved solid, stirring the obtained product, adding a NaBH4 solution into the obtained product, and carrying out reaction on the obtained mixture at room temperature; and adding triethylamine and acetic anhydride into the obtained object, and after the reaction is completed, carrying out dialysis and freezing on the obtained product so as to obtain pegylation modified hyperbranched polymine coated nano-gold particles. According to the invention, the cheap and easily-obtained PEI is taken as a carrier, so that the cost of materials is reduced; the surface of PEI is modified by using mPEG-COOH, so that the biocompatibility of materials and the colloidal stability of nano-gold particles are improved, and the nano-gold particles are successfully applied to vivo CT (computed tomography) imaging. The method disclosed by the invention is simple in design, mild in reaction conditions and easy to operate, and has an industrialized implementation prospect.

The invention relates to a preparation method for chiral dendrimers / gold nanoparticles modified by mPEG (Methoxy Polyethylene Glycol), comprising the steps of: (1) modifying the chiral dendrimers by using mPEG-MAL (Maleimide) and dialyzing, freezing and drying to obtain solids; (2) dissolving the solids with methanol or water, and adding a chloroauric acid solution and then a NaBH4 solution after mixing, reacting at a room temperature; and then adding triethylamine and acetic anhydride, dialyzing a reaction product after the reaction is ended and freezing to obtain a final product by. The invention has the advantages of increasing molar ratio of the gold to the chiral dendrimers and reducing cost of materials, and at the same time enhancing stability of the gold nanoparticles and being successfully applied in the mice's in-vivo imaging; and the method has the advantages of simpleness, mild reaction conditions and easy operation, and has the prospect for the implementation of industrialization.

The invention discloses a polygonal superhard abrasive compound and a method for manufacturing an abrasive tool with the same. The polygonal superhard abrasive compound is synthesized through high temperature and high pressure after polygonal grooves of a graphite die are filled with abrasive powder and synthesis blocks are assembled. Due to the fact that the polygonal superhard abrasive compound is the abrasive material which is regular in shape and synthesized through high temperature and high pressure after the polygonal grooves of the graphite die are filled with the abrasive powder and the synthesis blocks are assembled, the hardness is high, and the toughness is good; the size dimension is controllable, the particle size is uniform, and good grinding performance is achieved; the shape is regular, the sharpness of the abrasive material is further improved, the abrasive tool with abrasive material cutting edges evenly distributed in a space can be obtained conveniently, the grinding quality and the grinding effect of the abrasive tool can be improved, and the polygonal superhard abrasive compound and the abrasive tool are suitable for application and popularization.

The invention provides a preparation method of a surface-enhanced Raman scattering probe, relating to a preparation method of a silver nano aggregation probe which has high surface-enhanced Raman scattering activity and is coated by polyvinylpyrrolidone, as well as applications thereof in regulation of aggregation degree of silver nano particles and SERS detection in cells. The method selects silver colloid solution as a raw material, selects sodium chloride as an aggregation agent, and coats the polyvinylpyrrolidone on the surface of silver aggregates; and specifically comprises the following steps: evenly mixing Raman markers and the silver colloid solution according to volume ratio of 1: 1000 to 1:100 under the stirring condition, then adding sodium chloride solution to aggregate the silver colloid solution mixed with the Raman markers into aggregates with two to five particles, finally adding the polyvinylpyrrolidone solution, continuously stirring for 5 to 15 minutes, filtering the obtained solution with a filter with the aperture specification of 100 to 220nm and then obtaining the surface-enhanced Raman scattering probe. The probe is water-soluble colloid solution.

The invention relates to a composite membrane counter electrode used for dye-sensitized solar cells (DSSC) and a preparation method thereof, solving the problem that platinum counter electrodes of the existing DSSC have high preparation cost. The composite membrane counter electrode of the invention comprises a conductive substrate, a carbon material membrane and a polypyrrole membrane. The preparation method of the invention comprises the following steps: first preparing electrophoretic liquid of the carbon material and then electrophoretically depositing the carbon material membrane on the conductive substrate; preparing electrodeposition liquid of pyrrole and depositing the polypyrrole membrane on the carbon material membrane by cyclic voltammetry to obtain the carbon material / polypyrrole composite membrane counter electrode. The composite membrane counter electrode of the invention has good catalytic performance, good electrochemical stability, high conductivity and low preparation cost. The photoelectric conversion efficiency of the DSSC based on the composite membrane counter electrode of the invention reaches 4.267%, which is equivalent to that of the existing DSSC based on the Pt counter electrodes.

The invention provides a preparation method of a glass rod surface micro-lens array. The preparation method comprises the steps of placing a glass bar with a micro-lens array to be prepared on a femtosecond processing platform; controlling the femtosecond processing platform to move as processing requirement, and synchronously controlling the irradiation of a single point, and ablating to generate a crater array on the surface of the glass bar; and transferring the glass bar with the ablated crater into a diluted hydrofluoric acid solution, and heating under the ultrasonic water bath for providing assistance, and removing the glass bar from diluted hydrofluoric acid solution, and sequentially washing through acetone, absolute ethyl alcohol and deionized water under an ultrasonic water bath condition, thus obtaining the glass bar with the micro-lens array on the surface. According to the preparation method, the technology of etching under a wet chemical method along with the assistance of femtosecond laser point-by-point irradiation is adopted to prepare a high-quality micro-lens array on the surface of the glass bar.

The invention relates to a magnetic powder core in-situ preparation method. Nanometer ferrite particles with uniform particle sizes are prepared on the surface of a magnetically soft alloy powder surface with a sol-gel method in an in-situ manner, and the pressing and heat treatment processes are adopted to prepare a novel ferrite composited magnetic powder core. The magnetic powder core in-situ preparation method has the advantages that: (1) the sol-gel method is adopted to prepare the Mn-Zn and Ni-Zn ferrite in an in-situ manner, so as to prepare the nanometer particles with uniform and controllable sizes conveniently; (2) the ferrite used as the insulation cladding agent of the magnetically soft alloy powder can overcome the disadvantage that the magnetic property of the base body is reduced when being clad by the traditional non-magnetic substances as the cladding agent, thereby acquiring high magnetic conductivity and saturation magnetization.

The invention provides a preparation method of a polystyrene foam microsphere. The preparation method mainly comprises the steps of: by virtue of manners of introducing a pore-forming agent into a polystyrene solution and introducing microbubbles through ultrasonic oscillation, preparing water-in-polystyrene-solution composite emulsifiable particles or polystyrene solid emulsifiable particles by virtue of a microfluidic technology, removing an organic solvent for dissolving a polystyrene-based polymer by virtue of a spin evaporation method and drying to remove water and residual solvent, thereby obtaining the polystyrene foam microsphere with narrow particle size distribution. The foam microsphere can be widely applied in the fields such as chemical catalysis and high-energy physical experiments.

The invention relates to a sequential controllable nanometer silicon quantum dot array resistive random access memory and a preparation method thereof, and belongs to the technical field of non-volatile memories. The resistive random access memory comprises P and a silicon substrate material, and is characterized by also comprising a resistive silicon quantum dot multilayer film nanometer column array attached to the substrate material and an upper electrode and a lower electrode which are attached to the upper surface of the resistive silicon quantum dot multilayer film nanometer column array and the lower surface of the substrate; an insulating medium layer is arranged in the resistive multilayer film nanometer column array; and a silicon quantum dot multilayer film nanometer column is formed by at least two layers of silicon-enriched silicon nitride films which are inlaid with nanometer silicon quantum dots and have different nitrogen components or a silicon-enriched silicon oxide film sublayer which is inlaid with the nanometer silicon quantum dots and has different oxygen components. The sequential controllable nanometer silicon quantum dot array resistive random access memory can be compatible with the current micro-electronic process technology, and can show the advantage of sequential controllable nanometer silicon in resistive random access memory materials to fulfillthe aim of improving the switch ratio and stability of the resistive materials, so that nanometer silicon quantum dots are applied in silica-based nanometer memories in future.

The invention discloses a method for preparing preparing nano silver particles with controllable grain size uniform size through a seed growth method. In an ice-water bath, sulfhydryl compound and a silver source solution are mixed, and then are pre-protected, a weak reducing agent is added, in the ice-water bath, a strong ice reducing agent is added dropwise for reducing the silver source solution, stirring is carried out, the small-size nano silver particles with the uniform grain size are obtained, the nano silver particles serve as seeds, a certain amount of silver source solution is addedcontinuously, the strong reducing agent is used for reducing, and the controllable growing nano silver particles are obtained. The method has the beneficial effects that the produced nano silver particle products are uniform in grain size, and the size is controllable.

The invention provides a rare-earth doped modified graphene composite material gas sensitive element for detecting NOx and a preparation method of the gas sensitive element, and relates to a gas sensitive element for detecting the NOx and the preparation method of the gas sensitive element, solving the problems that an existing gas sensitive material is low in sensitivity, slow in response, and poor in resistance to factors except gas concentration. The rare-earth doped modified graphene composite material gas sensitive element for detecting the NOx is prepared from graphene, distilled water, a cupric acetate solution, a ceric nitrate solution, a sodium hydroxide solution and a glucose solution; an obtained rare-earth doped modified graphene composite material is mixed with a dispersant and a dispersion solution is dropwise added to the surface of a gold interdigital electrode to prepare the rare-earth doped modified graphene composite material gas sensitive element. The preparation method comprises the following steps: 1, preparation of the rare-earth doped modified graphene composite material; and 2, assembling of the composite material gas sensitive element.

The invention discloses a novel near-infrared quantum-dot-doped aluminium phosphate mesoporous glass nanometer compound and a preparation method thereof. The PbS-quantum-dot AlPO4 mesoporous glass nanometer compound is AlPO4 mesooprous glass doped with PbS quantum dots with different dimensions. The preparation method of the quantum-dot-doped aluminium phosphate mesoporous glass nanometer compound comprises the following steps: step 1, preparing a PbS quantum dot solution with two kinds of luminescence peak-value wavelength and a mixed solution with fresh quantum dots and ripened quantum dots; step 2, immersing AlPO4 mesoporous glass prepared by employing a sol-gel method in the quantum dot solution of the step 1 for one time or for independently two times; and step 3, taking the immersed mesoporous glass out from the solution, and performing moistening washing and drying to obtain the PbS-quantum-dot AlPO4 mesoporous glass nanometer compound. Tests prove that under pumping of near infrared, the PbS-quantum-dot AlPO4 mesoporous glass nanometer compound is capable of generating broadly tunable luminescence or double-peak luminescence at near infrared wave band, and has important application to the field of broadband optical transmission, multiband response optical communication materials and devices.

A composite particle material containing spherical and miniporous zine oxide and SiO2 is prepared through such steps as dispersing SiO2 particles in the alcohol-water mixed solvent, preparing the aqueous solution of zine salt, preparing the aqueous solution of hydramine compound, adding the last two solutions to the first one, ageing, and centrifugal separation. The said material can be used for photon crystal assembly, electrorheopectic material and high-grade paint.

The invention discloses a low-temperature dynamic constraint loading-sintering method for preparing metal porous materials. A preparation process is as follows: to-be-sintered metal blank or powder is directly put into a sintering mold; a heat-resistant loading weight with a limiting stopper is placed on the to-be-sintered metal blank or powder; the gravity of the loading weight is utilized to apply pressure to the to-be-sintered metal blank or powder; then the sintering mold is placed in a vacuum sintering furnace; and low-temperature dynamic constraint loading-sintering is performed under the condition lower than a common metal porous material sintering temperature, so as to prepare the metal porous materials. The low-temperature dynamic constraint loading-sintering method adopted by the invention comprises the following steps of adopting a loading mold with simple structure in a common powder-metallurgy vacuum sintering furnace, utilizing the deadweight phenomenon of the mold to mutually bond metal particles thermally softened and finishing sintering the metal porous materials at a low temperature, which avoids the phenomenon that metal high-temperature grains grow up. The metal porous materials are adjustable in size and controllable in porosity. The method has the advantage of greatly reducing production cost, along with simple process.

The invention relates to a high-porosity dry powder inhalant carrier and its supersaturated synthesis method and application. The carrier is a flower-shaped porous dry powder particle with a rough surface. The median diameter of a single particle under an electron microscope is 0.5-50 microns. The carrying capacity of drug molecules is 5-50% mass fraction, and the N2 adsorption specific surface area of ​​the carrier is 10-100 square meters per gram, containing micro, medium and macro pores. For the first time, the present invention combines supersaturated synthesis technology and flower-shaped material preparation technology, and applies it to the field of dry powder inhalants. Using the synthesis method provided by the invention, the high-porosity dry powder inhalant carrier is prepared with controllable size and high performance. The porosity nanopore system is used for the adsorption, carrying and transportation of nano-level and molecular-level components, with good uniformity, stability and transmission efficiency. The invention realizes efficient, high-quality, cheap and practical mass production of nano- and micron-level high-porosity dry powder inhalant carrier materials.

The invention belongs to the technical field of organic polymer chemistry and nano-composite materials and discloses a synthetic method of a polyaniline / carbon fiber composite material with a nano-ordered structure. The synthetic method comprises the following steps: dispersing carbon fibers, phenylamine and ammonium persulphate in 0.5-2 mol / L of perchloric acid solution and ensuring that in an obtained carbon fiber / phenylamine / ammonium persulphate system, the molar ratio of phenylamine to ammonium persulphate is (1-3):1, and the final concentration of the carbon fibers, the phenylamine and the ammonium persulphate is 0.1-0.5 mg / ml, 0.4656-4.656 mg / ml and 1.141-11.41 mg / ml; and transferring the carbon fiber / phenylamine / ammonium persulphate system into an ice-water bath, keeping the temperature to be 10 DEG C below zero to 5 DEG C, agitating for 3-14 hours at a constant temperature, and collecting and drying to obtain a target product. The synthetic method has the beneficial effects that not only the ordered structure formed by polyaniline self-assembly is realized, but also the size adjustment and control of the ordered structure are realized; and the polyaniline / carbon fiber composite material with the nano-ordered structure obtained by the invention has the advantages of uniform size, high orderliness and excellent electrochemical stability and can be used as an electrode material.

The invention provides quantum dots and a preparation method thereof. The preparation method comprises the following steps: (1) mixing a body material, a grinding aid material and a ball milling ball,and carrying out ball milling to obtain a crude product; and (2) mixing the crude product obtained in the step (1) with a solvent to obtain a mixed solution, and carrying out ultrasonic treatment onthe mixed solution to obtain the quantum dots. The preparation method is a top-down preparation strategy, a macro-scale body material is used as a raw material, the body material is effectively crushed through the synergistic combination of two physical methods of ball milling and ultrasonic treatment, and finally, the nano-scale quantum dots with uniform particle size are obtained. The preparation method has the advantages of being efficient, environmentally friendly, easy to operate, low in cost and the like, is suitable for large-scale production and has good application prospects, the prepared quantum dots are high in purity, good in dispersity, high in yield, uniform in particle size and controllable in size, and the preparation method has important guiding significance in achieving industrial application and accelerating the industrial process of the quantum dots.

The invention discloses a panchromatic Micro-LED array display and white light device based on III-nitride / organic semiconductor hybrid structure, which mixes inorganic and organic light emitting diode devices to obtain high-efficiency ultra-high-resolution active Micro-LED display and lighting source. A red-light, green-light or yellow-light organic material is evaporated on an N-type gallium nitride layer of a InxGa1-xN / gallium nitride quantum well blue-light LED epitaxial wafer having a p-n structure, respectively, and an electron transport layer, a luminescent layer, an exciton blocking layer, a hole transport layer and a hole injection layer are included in sequence; and when one of the groups of materials is evaporated, other pixels are shielded using a shielding mask. The technologycombines the organic semiconductor material and inorganic semiconductor material, and can realize a novel inorganic / organic semiconductor hybrid structure Micro-LED device array which has the characteristics of high efficiency, wide color gamut, low power consumption and fast response time.

The invention discloses a monodisperse transition metal nanocatalyst for Fischer-Tropsch synthesis as well as a preparation method and application thereof. The catalyst comprises transition metals, wherein the transition metals are stably dispersed in an organic solvent in a monodisperse metal nanoparticle state; the particle size of the transition metal is 1-100nm; and the specific surface area of the catalyst is 5-300m<2> / g. According to the method disclosed by the invention, the particle size of the active ingredients can be regulated and controlled, so that the size of the metal nanoparticles is controllable, and the metal nanoparticles do not need to be embedded into a carrier surface; and therefore, the specific surface area of the active ingredients is enlarged, and the catalytic performance of the catalyst is improved. According to the catalyst disclosed by the invention, the dispersity of the metal nanoparticles is high, and when the catalyst is used for a slurry bed reaction system, the catalyst can be directly applied to a Fischer-Tropsch synthesis reaction without complicated filtering separation, cleaning, high-temperature roasting and activated reduction, and the catalyst has extremely excellent catalytic activity.

The preparation process of porous spherical granular inorganic material includes adding chitin slurry with high inorganic powder content, dimethyl acetylamine as solvent and with or without pore creating agent into emulsifier through stirring to emulsify into sol-like spherical grain; adding water in controlled form for in-situ gelatinizing to form, filtering and washing with acetone or alcohol to eliminate emulsifier, water soluble solvent and pore creating agent to obtain porous spherical gel grain; drying to obtain initial blank, roasting, mechanical shaping and sintering to obtain product. The product has high sphericity, wide size range, narrow size distribution, controllable porous form and high mechanical performance, and may be used widely as body tissue repairing and stuffing material, tissue engineering rack material, medicine releasing carrier, filtering material, etc.

The invention provides a method for producing the zirconia porous ceramics, which solves the problems of the production technique of the existing zirconia porous ceramics is hard to control, the distribution of the porous in the obtained material is irregular with poor uniformity. The method comprises the following steps of: (1) wetly mixing the ZrO2C10H16 and polystyrene to obtain paste; (2) pre-cooling the paste and then freezing the paste; (3) demoulding and drying the frozen paste, then carrying out heat-insulating and sintering and re-cooling to the room temperature to obtain the zirconia porous ceramics. The production technique of the invention is easy to control and the distribution of the porous in the obtained material is regular with good uniformity.

The invention provides a preparation method of a three-dimensional carbon network coated Ni2P nano particle composite material. The preparation method comprises the following steps: first step: preparing three-dimensional carbon network coated Ni / NiO nano particles, dissolving nickel salt, citric acid and sodium chloride into deionized water, then stirring, and performing freeze drying to obtain aprecursor, performing a high temperature treatment on the precursor in an inert atmosphere, performing cooling, washing and vacuum drying to obtain Ni / NiO@C, placing the product in an HCl solution, then etching the product for a certain time to obtain Ni / NiO@C composite materials with different sizes, and step 2: preparing three-dimensional carbon network coated Ni2P nano particles (Ni2P@C): weighing Ni / NiO@C and sodium hypophosphite, respectively placing the same in two independent porcelain boats, placing the porcelain boat containing sodium hypophosphite near one end close to an air vent,placing the porcelain boat containing the Ni / NiO@C at the middle of a tube furnace, and calcining to obtain a Ni2P@C composite material.

The invention provides a method for preparing a porous polymer film by a bubble template method. The method utilizes a structure that a bubble generated by a capillary-based microfluidic device is assembled at a two-phase liquid interface as a template, wherein, a lower layer of the interface is liquid having a small viscosity, and an upper layer is a polymer solution, when the bubbles rise to thetwo liquid interfaces, the bubbles can be arranged to form a stable structure, under ultraviolet exposure or heating conditions, the upper layer of the polymer solution is cured, the bubbles are ruptured or overflowed, channels can be formed, and the porous polymer film can be prepared. The method simplifies the step of removing the template by using a solvent in the preparation of the conventional template method, and can avoid the influence of the solvent on the properties of the polymer film. The bubble generated by the method has a controllable size and a high production speed, and teh polymer film with the controlled pore size can be prepared in a short time.

The invention discloses a conductive aluminum lithium ion adsorption column material and a preparation method thereof. The preparation method comprises the steps that a dispersing agent and an organicsolvent are mixed to be uniform, and first mixed liquid is formed; aluminum hydroxide, lithium hydroxide and a cross-linking agent are mixed to be uniform, and second mixed liquid is formed; after the first mixed liquid and the second mixed liquid are mixed, heating is carried out, polymer monomers and an initiator are added to react, finally conductive organic matter monomers and a solid conductive material are added to be subjected to a polymerization reaction, and the conductive aluminum lithium ion adsorption column material is obtained. According to the conductive aluminum lithium ion adsorption column material and the preparation method thereof, the lithium hydroxide is inserted into the layered compound aluminum hydroxide, and is combined with acidic or basic groups of the polymermonomers, carboxy groups on the surface of an obtained polymer and aniline are subjected to secondary crosslinking, and a conductive polyaniline surface coating is prepared; meanwhile, the surface ofthe polymer is bonded with inorganic conductive powder during secondary crosslinking, and the obtained lithium ion adsorption column material is good in mechanical strength, high in selectivity, largein capacity and good in stability and electrical conductivity.

The invention relates to a sustained-release mildewproof / antibacterial and self-cleaning bifunctional casein-based nanometer microcapsule coating material and a preparation method thereof. The preparation method comprises the following steps: adding casein powder into a weak acid solution, performing stirring dissolution and cooling to obtain a solution A, adding a mildewproof agent or antibacterial agent, polymeric micelles, tetrabutyl orthotitanate and a coupling agent into an organic solvent, performing stirring dissolution and cooling to obtain a solution B, and slowly adding the solution B into the solution A for continuous stirring, so as to obtain a target product. According to the material and the preparation method thereof, a mildewproof agent or antibacterial agent coated polymer-based inorganic composite nanometer microcapsule is prepared by adopting casein as a substrate, introducing the mildewproof agent or the antibacterial agent into a core layer and introducing an inorganic nanometer shell layer in a precursor hydrolysis manner, and is nanometer-scale, uniform in size distribution and controllable in size; the inorganic nanometer shell layer is nanometer titanium dioxide, and a coating self-cleaning effect can be achieved under ultraviolet irradiation, so that the material has mildewproof / antibacterial and self-cleaning bifunctionality.

The invention relates to a preparation method of chitosan aspartate 5-fluorouracil-loaded nanoparticle. The invention makes use of the process to form the ionic compound of chitosan and aspartate to carry out the loading of 5-fluorouracil, so as to prepare the chitosan aspartate 5-fluorouracil-loaded nanoparticle water dispersion system by changing the molecular weight, molar ratio, reaction conditions and other factors of the raw materials under the mild reaction conditions, and the nanoparticle powder is obtained by freeze drying. The chitosan aspartate 5-fluorouracil-loaded water dispersion system of the invention is the nanoparticle with even dispersion and spherical shape. The product of the invention can be re-dispersed into the nanoparticle in water and has certain target and sustained-release performances. The invention has simple method and easy obtainment of raw materials; compared with the oral formulations on the market, the intestinal absorption efficiency and the bioavailability of the invention are significantly improved after oral administration, so the invention has better efficacy on malignant tumors.

The invention provides a low-dimension method for nano-wires. The low-dimension method comprises the following steps: dispersing the nano-wires in a solvent, setting the temperature and stirring; and carrying out ultrasonic treatment to realize low dimension of the nano wires so as to obtain nano-particles. Compared with an existing method, the method has the advantages of extensive sources, simplicity and convenience in operation and the like. By the method, the nano-wires are converted completely, the number of the obtained nano-particles can be increased remarkably, and the prepared nano-particles are quite high in purity and uniform in grain size. Meanwhile, the problems that the cost is high, the process is complicated and products are difficult to produce on a large scale in the prior art are solved. The application prospect is good.