272 results about "Gamma ray irradiation" patented technology

Decellularization of tissue by means of an amphipathic solvent a well-established practice. However, situations exist where the provision of enhanced decellularization is preferred. There is a demand for treating methods for coping with such situations. Thus, it is intended to provide a method for enhancing decellularization. The method comprises not only the immersing of a tissue in a solution containing an amphiphilic molecule in non-micellar form (for example, 1,2-epoxide polymer) but also performing a radical reaction (for example, treatment selected from the group consisting of exposure to gamma-ray irradiation, ultraviolet irradiation, a free radical supply source, ultrasonication, electron beam irradiation, and X-ray irradiation).

The invention relates to a method for treating sewage, in particular to a method for treating organic sewage by the synergy of a cavitation effect and sulfuric acid free radicals. The method comprises the following steps of: adding an oxidant and a catalyst into organic pollutant-containing sewage, and performing oxidative degradation on organic pollutants under the action of the cavitation effect. The cavitation effect is an ultrasonic or hydraulic cavitation effect, preferably the hydraulic cavitation effect; the hydraulic cavitation effect is a jet cavitation effect or an eddy cavitation effect; the jet cavitation effect is generated through a pipe of which the diameter is changed rapidly; and the eddy cavitation effect is generated through a cylinder type eddy cavitation bin. The cavitation effect is applied to the process of treating the sewage by the sulfuric acid free radicals, so that the generation efficiency of the sulfuric acid free radicals is improved, and the degradation rate of the organic pollutants in water is improved; in the method, reaction conditions are simple and mild, a high temperature and ultraviolet ray and gamma ray irradiation are not needed, and a pH value has a wide application range and does not need to be adjusted; and the reaction speed is high, and the using amount of the oxidant is reduced; and the treatment efficiency is high, and the method is suitable for treating a large amount of the sewage.

The invention discloses a hydrothermal preparation method for NiS2 with a controllable shape, and the method mainly comprises the following steps of: mixing nickel salt, a sulphur source and a complexing agent in a certain molar ratio, transferring the mixture into a high-pressure reactor, adding distilled water, and stirring to adequately dissolve soluble solids; adjusting the pH value of the reaction system, sealing the reactor, and reacting at a certain temperature; and washing the obtained product by use of distilled water and ethanol respectively, centrifugally separating, and drying. The hydrothermal preparation method for NiS2 with a controllable shape disclosed by the invention has the advantages of being simple in operation by using a hydrothermal method, moderate in reaction condition, narrow in particle size distribution, high in product purity, easy in industrial production, and the like. The particle shape and size of NiS2 can be controlled by adjusting the synthesis conditions such as hydrothermal reaction temperature, reaction time, complexing agent type and pH value, and the prepared NiS2 can be approximately-cube-shaped, spherical, sheet-shaped and the like. Compared with a solid-state reaction method, an ultrasonic spray pyrolysis method, a gamma-ray irradiation method and an organic solvent hot method, the NiS2 prepared by the hydrothermal method has the advantages of being low in reaction temperature and equipment demand, less in toxicity on a human body, high in safety factor, low in production cost, capable of meeting the requirements of energy conservation and emission reduction, and the like.

The invention belongs to the field of composite shielding material technology, and especially relates to an aluminium-based composite material used for nuclear reactors to shield neutrons and gamma rays as well as a preparation method thereof. The composite material employs pure aluminium as a basis material, and shielding components are tungsten and boron carbide; the mass percent of tungsten is 20-70%; the mass percent of boron carbide is 1-10%; the balances are aluminium and unavoidable impurities. The aluminium-based composite material with certain mechanical strength as well as excellent nuclear reactor neutron and gamma ray irradiation resisting properties is developed by using an isostatic compaction method according to needs of some nuclear power reactors; the material whose thickness is 10cm can ensure that the transmittance of gamma rays whose power spectrum is 0.1-2MeV is reduced to 20% or less, and at the same time absorption effects of the composite material to thermal neutrons are substantially obvious.

During the preparation of composite aramid fiber/polyimide material, aramid fiber is first surface modified via gamma-ray irradiation of dosage 300-500 kGy in nitrogen atmosphere to raise surface activity; the surface modified aramid fiber, additive polyimide powder, PTEF and graphite are then airflow crushed and mixed in an air flow crusher of air pressure 4-6 MPa; the mixture powder is hot pressing molded at 200-240 deg.c and 16-23 MPa for 0.5-1 hr. Thus prepared composite aramid fiber/polymide material has excellent mechanical performance and friction performance and may be used in the structural part and friction part in aeronautic and astronautic fields.

The natural flower health drink, including flower wine, flower honey and flower tea, is prepared with over 100 kinds of wild flowers and through stoving, gamma ray irradiation and soaking in wine, honey or drinking water. The selected wild flowers contain amino acid, natural enzyme, vitamins, cyanidin, aromatic oil and other matters essential for human life activity, some matters with antisenility, antifatigue, anti-cancer and antibacterial functions and trace elements needed by human body.

The invention provides a silicon rubber self-adhesive tape which belongs to the technical field of chemical product manufacturing. The silicon rubber self-adhesive tape is made from methyl vinyl silicon rubber, fume silica, tackifier, vinyl silicon oil and iron red; the production technology comprises the steps of mixing the raw materials and placing the mixture in a gamma ray irradiation field of 60Co for radiation vulcanization. The product not only satisfies the manufacturing need of a special engine, but also can serve as an insulation protection product under high temperature and high pressure for electric insulation protection of a large-scale motor, an electromotor, special machines, and the like, and can satisfy the strong insulation sealing requirement on the industries such as shipbuilding, mining, petroleum production, chemical engineering, steel making and the like under severe environments of specially high temperature and high pressure.

The invention discloses a preparation method of a graphene-coated lithium nickel cobalt manganate composite material. The method comprises the following steps of preparing graphene with properties ofeasy separation, high water dispersity and high electrical conductivity in a green and efficient manner by combination of a water phase "intercalation-expansion-oxidization" method and a gamma-ray irradiation reduction technology; by adopting a high-temperature calcining method and by taking spherical manganese dioxide as a template, skillfully preparing a spherical ternary material which has a hollow structure and is formed by nanometer lithium nickel cobalt manganate primary particles, and performing surface modification treatment on the spherical ternary material; and further controlling proper conditions to enable graphene to be uniformly and firmly coated on the surface of lithium nickel cobalt manganate to obtain the target composite material. The raw materials involved in the invention are low in cost, the preparation process is high in controllability, and adopted water or an ethyl alcohol solvent is environment friendly; the composite material is excellent in electrochemical performance; the specific capacity can be as high as 265 mAh g<-1>; and after 500 cycles, the capacity retention rate can be 86%, so that the composite material can be widely applied to the lithium ionbattery and other electrochemical energy storage devices.

A preparation method of a hydrophobic separating membrane. The method comprises the following steps: dissolving hydrophobic monomers and a conventional polymer membrane production material A in a solvent to form a homogeneous solution, conducting gamma ray irradiation treatment on the homogeneous solution to induce a grafting reaction to obtain a hydrophobic graft polymer B, dissolving or dispersing the hydrophobic graft polymer in B in an organic solvent to form a membrane production liquid, and spraying or coating the membrane production liquid on the porous base membrane surface to form a hydrophobic separating membrane. The hydrophobic separating membrane can be used in membrane distillation, membrane absorption, membrane extraction, steam penetration, penetration vaporization or oil-water separation process. The invention overcomes the defects of complex membrane preparation process, narrow material selection range, poor hydrophobic stability and uneasily controlled pore structure in the prior art for preparation of hydrophobic separating membrane. The separating membrane prepared through the method provided by the invention has the advantages of controllable pore size, strong hydrophobicity and good hydrophobic stability, etc.

The invention relates to a medical polyvinyl chloride (PVC) material for gamma-ray irradiation disinfection and a preparation method thereof. The medical PVC material comprises 100 parts of PVC resin, 40 to 70 parts of a plasticizer dioctyl phthalate (DOP), 1.0 to 1.5 parts of a calcium/zinc heat stabilizer, 5 to 8 parts of an auxiliary heat stabilizer, 0.3 to 0.5 parts of a yellowing inhibitor, 0.1 to 0.5 parts of an anti-oxidant and 0.5 to 0.8 parts of a lubricant, wherein the PVC resin is a suspension PVC resin having a polymerization degree of 2500 to 3000; the calcium/zinc heat stabilizer is a complex composed of 50 to 60% of ricinic acid calcium, 10 to 15% of zinc octanoate, 10 to 15% of zine stearate and 10 to 25% of sorbierite; the auxiliary heat stabilizer is epoxidized linseed oil; the lubricant is composed of 40 to 60% of stearic acid and 40 to 60% of polyethylene wax; the yellowing inhibitor is octadecyl-dibenzoylmethane; and the anti-oxidant is an anti-oxidant 1076 produced by the Ciba specialty chemicals Ltd. The medical PVC material solves the problems that after being subjected to irradiation disinfection, the existing PVC material yellows because of degradation breaking of PVC macromolecules; mechanical properties are reduced; and ageing is accelerated. The preparation method of the medical PVC material can obviously improve a PVC material anti-irradiation capability.

The invention relates to a method for preparing a core-shell structure composite material by Gamma-ray irradiation, relating to a preparation method of a core-shell structure composite material. The invention solves the defects of multiple steps, easy side product introduction and difficult scavenging of side products during the reduction of a reducing agent in preparing the core-shell structure composite material by using a traditional chemical plating method. The method comprises the steps of: firstly, purifying nano materials or micron materials, adding into a metal salt solution, then adding a free radical scavenger, adjusting pH value, and ultrasonically dispersing; and secondly, irradiating by using Gamma-rays, washing, centrifugally separating, and drying in vacuum. The method has mild reaction condition, simple operation, strong controllability, good repeatability, less content of purities of products, and stable quality of obtained products.

The invention discloses a polyether ether ketone composite used for a solid positioning head frame and a preparation method thereof. The polyether ether ketone composite comprises the components with the weight percentage as follows: 35-52 percent of inorganic filling, 3-5 percent of modifier, 25-35 percent of matrix resin and 20-25 percent of reinforcing fiber. The reinforcing fiber is arranged in epoxy acetone solution to be soaked, subjected to gamma ray irradiation treatment and is dried subsequently; the polyether ether ketone is arranged in oxygen, hydrogen or argon plasma atmosphere to be irradiated for 30 minutes and then is subjected to banburying with the modifier and the inorganic filling in proportion as above; a product and chopped carbon fiber are added into a double-screw extruder to be extruded and granulated; plastic granules are dried, injected and pressurized at constant temperature and then are molded into the solid positioning head frame. In the invention, the proportion for producing the raw materials is lightened and the performance of the polyether ether ketone composite in CT/MRI working environment is improved.

The sensitizing and readiation degrading process of preparing low molecular weight chitosan includes the following steps: mixing refined solid chitosan with water solution of sensitizer to form semi-solid sample, regulating pH to 4 with inorganic acid or organic acid and reaching chitosan concentration of 16-25 wt% and sensitizer concentration of 15-30 wt%, gamma ray irradiation in the dosage of 1-10 kGy to degrade at room temperature, and spray drying or vacuum drying to obtain low molecular weight chitosan. Adding the sensitizer can lower the irradiation dosage greatly, and obtain chitosan product with narrow molecular weight distribution and small molecular weight. The present invention can obtain chitosan with molecular weight as low as 3000, and the process is convenient, safe, economic, practical, high in yield and environment friendly.

The invention discloses a method for preparing a water-soluble cross-linked polymer grafted carbon nano tube, which comprises the following steps: adding a carbon nano tube, a polymerizable macromolecular surfactant, a vinyl monomer and an initiator dispersed in an organic solvent into water, and ultrasonically oscillating or stirring the mixture to form stable suspension; and under the atmosphere of nitrogen, heating and reacting the obtained suspension or irradiating the obtained suspension with gamma rays so as to produce free radical polymerization between the polymerizable macromolecular surfactant and the vinyl monomer, centrifuging or filtering the suspension, and drying the centrifuged or filtered product to obtain the water-soluble cross-linked polymer grafted carbon nano tube. The preparation method of the invention is simple, does not need strong acid and strong alkali during the preparation, has mild reaction process, and is easy in scale production. Because the molecule of the polymerizable macromolecular surfactant contains over one double-bond which can directly participate in the polymerization reaction so that a polymer coating produces chemical crosslinking and is grafted to the surface of the carbon nano tube, the polymer coating has quite good structural stability; and the method of the invention can prepare the polymer modified carbon nano tube with good water solubility and quite stable structure.

The invention provides a method for modifying polyacrylonitrile (PAN) by using gamma ray irradiation. Being subjected to the gamma ray irradiation in air, inert atmosphere or a vacuum, the heat release of the cyclized PAN can be reduced in the process of heat treatment; and being subjected to the pretreatment of the gamma ray irradiation, the pre-oxidation rate of PAN fiber can be obviously increased. Undergoing the changes in performance, the invention can help control the sharp rise in the temperature of a sample and accelerate the oxidation in the process for PAN fiber or films to carry out high-temperature cyclization or oxidation crosslinking, particularly, the process of precursor pre-oxidation crosslinking for preparing PAN-based carbon fiber. Accordingly, the method of the invention is of potential application value to the reduction in production cost for PAN oxidation products, particularly, the reduction in production cost for PAN-based carbon fiber.

The invention provides fiber base protein molecularly imprinted polymer aquagel and a preparation method thereof. The fiber base protein molecularly imprinted polymer aquagel comprises the following components by weight percent: 1.78-3.96 percent of polypropylene fiber (PP) non-woven cloth, 8.9-21.38 percent of acrylamide, 0.22-2.85 percent of N,N'-methylene-bis-acrylamide, 0.05-1 percent of protein and 71.26-89.06 percent of de-ionized water. The preparation method comprises the following steps of: adding the protein, the acrylamide and the N,N'- methylene-bis-acrylamide based on the component ratio into the de-ionized water to obtain mixed solution A, immersing the polypropylene fiber non-woven cloth into a test tube containing the mixed solution A; performing gamma-ray irradiation on the test tube with the reaction mixture under the condition of radiation dose rate of 0.05-1kGy/h, scraping polyacrylamide gel of fiber surface layers by using nippers and eluting protein template to obtain the fiber base protein molecularly imprinted polymer aquagel.

The invention discloses a method for preparing functionalized graphene based on a high-energy irradiation one-step method. The method comprises the following steps of: mixing graphite oxide and polar small molecular organic solvent, and performing ultrasonic dispersion treatment on the mixed solution for 0.5 to 2 hours, wherein the polar small molecular organic solvent is one or more of epoxy chloropropane, styrene/ acetone solution, acrylic acid and lactic acid; and putting the dispersion in an irradiation source chamber of 60 Co, performing gamma ray irradiation on the mixed solution under the conditions that the irradiation dose rate is 0.6*10<3> to 6*10<3>Gy/h and the irradiation dose is 1*10<4> to 2*10<6>Gy, so that the surface of the graphite oxide is peeled, and functionalized graphene nano sheets are formed. By using the characteristics of high energy and strong penetrating power of gamma ray particles in the method, the functionalized small molecular organic substance intercalated into graphite oxide layers and the graphite oxide layers undergo grafting reaction, so that the distance between the graphite oxide layers is increased, and the graphene nano sheets are formed by peeling.

The invention discloses a carbon-based porous flexible composite wave-absorbing material and a preparation method thereof. The carbon-based porous flexible composite wave-absorbing material and the preparation method thereof are characterized in that pretreatment is conducted on one part of a carbon-based wave-absorbing agent, and then mixing molding is conducted on the treated carbon-based wave-absorbing agent, 0.2-0.4 part of a fluxing agent, 40-100 parts of silicone rubber, 10-30 parts of reinforcing agents, 0-5 parts of radiosensitizer and 0-3 parts of flame retardants; rubber materials molded through mixing are put into a mold, rolling is conducted on the rubber materials at 100-150 kg.cm<-2>, and a thin sheet with the thickness ranging from 0.5 mm to 5 mm is prepared; after plastic sealing is conducted on the thin sheet with the mold, the plastic-sealed thin sheet with the mold is put into a gamma-ray irradiation field or an electron beam accelerator to enable the total absorbed dose to be kept at 30-100 kGy, radiation crosslinking is conducted, after a plastic package and the mold are removed, edges are cut off, and the carbon-based porous flexible composite wave-absorbing material is obtained. According to the carbon-based porous flexible composite wave-absorbing material and the preparation method thereof, the technology is simple, complex chemical process control or professional auxiliary equipment is not needed, only simple equipment such as a double-roller mixing mill is needed, and the cost is lower; the prepared material is excellent in flexibility and wave-absorbing performance, the preparation process is easy and rapid to control, the repeatability is good, and energy conservation and environment protection are achieved.

The invention discloses a preparation method of a chitosan modified polylactic acid material by gamma-ray irradiation. The preparation method comprises the steps of performing melt blending on polylactic acid, a natural polymer material of chitosan and a sensitizer, wherein the mass ratio of chitosan to polylactic acid is 0.5:100-20:100 and the mass ratio of the sensitizer to polylactic acid is 0.5:100-10:100; then performing hot pressing, cooling and demoulding forming; putting the obtained material into an irradiation bag and sealing after vacuumizing or introducing nitrogen; and performing irradiation treatment by Co-60 gamma-ray at room temperature to obtain the chitosan modified polylactic acid material. The chitosan modified polylactic acid material prepared by the preparation method is good in thermodynamic property, the gel fraction is 60-85%, the glass transition temperature is 64-70 DEG C and the tensile strength is 68-79MPa, and the properties are remarkably improved in comparison with those before modification, so that the chitosan modified polylactic acid material is wide in application prospect.

The present invention discloses a fertilizer synergist and a preparation method thereof. The fertilizer synergist is prepared by the method comprising the following steps: (1) using gamma-ray for radiation of attapulgite placed in a snake leather bag, and treating the irradiated attapulgite with microwave; (2) mixing a silane coupling agent, the treated attapulgite and water for reaction to obtain silane-coupling-agent modified attapulgite; (3) mixing humic acid and the silane-coupling-agent modified attapulgite obtained by the step (2) for reaction to obtain a humic acid-attapulgite complex; and evenly mixing the humic acid-attapulgite complex and sodium carboxymethyl cellulose and sodium polyacrylate to obtain the fertilizer synergist. The fertilizer synergist allows the slow-release of fertilizer nutrients, but also can control nutrient loss. The fertilizer synergist can effectively improve the utilization rate of the fertilizer nutrients, reduces environmental pollution and promotes agricultural production increase.

The invention discloses an acid-proof, moisture-holding and superactive special fertilizer technology for forestry and an additive. The technology comprises the steps of mixing and adding attapulgite, straw ash of power plants, sodium hexametaphosphate and aminothiopropionic acid into tap water so as to prepare turbid liquid, adding acrylamide, N,N'-methylene bisacrylamide and hydrogen peroxide into the turbid liquid, carrying out gamma ray irradiation on the obtained mixture, drying the obtained product until the weight of the obtained product is constant, crushing and sieving the obtained product, mixing the obtained powder with ammonium polyacrylate so as to obtain a special fertilizer additive for forestry, adding the additive into a common fertilizer, and granulating the obtained mixture so as to obtain a special fertilizer for forestry. The fertilizer has the advantages of water holding, fertilizer maintenance and capability of improving the acidic soil; meanwhile, through taking straw ash of power plants as a raw material, the straw ash of power plants is changed into things of value, thereby saving the cost, and further facilitating the large-scale application of the technology and the additive in forestry.

The invention discloses composite polysaccharide for resisting radiation. Effective ingredients of the composite polysaccharide comprise lentinan, agaricus blazei polysaccharide and tuckahoe polysaccharide. The composite polysaccharide can obviously improve the immunity of mice, can enhance the white cell number and the bone marrow cell DNA content of the mice after gamma-ray irradiation, has stronger radiation resisting effect, and is particularly suitable for tumor disease radiation therapy and chemotherapy or adjuvant therapy after tumor disease operation.