995 results about "Photodegradation" patented technology

A food composition in which omega-3 fatty acids are stabilized against oxidation is disclosed. The food composition contains about 4 to about 100 weight percent of the composition in which triglycerides containing omega-3 fatty acids (and other fatty acids) are stabilized against oxidation in the absence of encapsulation. The fatty acid portion of the oil in the completed food composition includes less than about 10 percent by weight linoleic acid, at least 75 percent by weight of monounsaturated plus saturated fatty acids, and at least 3 percent by weight omega-3 fatty acids. The food composition can also contain comminuted peanuts, e.g., peanut butter, in which case the composition is also stabilized against photo-oxidation and the fatty acid portion of the oil portion of the food can contain less than about 15 percent by weight linoleic acid and at least 1 percent by weight omega-3 fatty acids. Methods of protecting a food composition from oxidation and photodegradation are also disclosed.

A synthetic method of a novel visible light photocatalyst Bi2MoO6 (bismuth molybdate) is provided. The method includes the following steps: weighing Bi(NO3)3*5H2O and (NH4)6Mo7O24*4H2O solids at the theoretical ratio by mass of 14:1, dispersing the weighed solids into an appropriate amount of deionized water, stirring to obtain white curdy precipitates, placing the precipitates in a magnetic stirrer and stirring at normal temperature for 30 minutes, subjecting to ultrasonic treatment with a ultrasonic generator for 30 minutes to allow intensively mixing, allowing reactions of the treated white precipitates at 150-200 DEG C under sealed conditions, filtering the reaction product to collect flavescent precipitates, washing, drying, and grinding to obtain Bi2MoO6 (bismuth molybdate) photocatalyst. The photocatalyst has good photodegradation effect on target pollutants; and when the temperature of hydrothermal synthesis is 160 DEG C, the removal rate of target pollutant 4BS after photodegradation for 90 minutes reaches 99.5%. The inventive synthetic method has the advantages of simple process and low requirement for equipment, and is suitable for the synthesis of highly-active visible light photocatalyst Bi2MoO6 (bismuth molybdate).

Polymers comprising a polymer backbone comprising one or more degradable units are described. The polymer may additionally comprise two or more polymer segments comprising radically (co)polymerizable vinyl monomer units. The degradable units may be independently selected from, but not limited to, at least one of hydrodegradable, photodegradable and biodegradable units between the polymer segments and dispersed along the polymer backbone. The degradable units may be derived from one or more monomers comprising a heterocyclic ring that is capable of undergoing radical ring opening polymerization, a coupling agent, or from a polymerization initiator, radically polymerizable monomers, as well as other reactive sources. Embodiments of the degradable polymer of claim are capable of degrading by at least one of a hydrodegradation, photodegradation or biodegradation mechanisms to form at least one of telechelic oligomer and telechelic polymeric fragments of the polymer. The degradable polymer may be able to degrade into polymer fragments having a molecular weight distribution of less than 5, or in certain applications it may be preferable for embodiments of the polymer to be capable of forming polymer fragments having a molecular weight distribution of the polymer fragments less than 3.0 or even less than 2.5. Embodiments of the present invention also include methods of producing degradable polymers.

An optically reliable high refractive index (HRI) encapsulant for use with Light Emitting Diodes (LED's) and lighting devices based thereon. This material may be used for optically reliable HRI lightguiding core material for polymer-based photonic waveguides for use in photonic-communication and optical-interconnect applications. The encapsulant includes treated nanoparticles coated with an organic functional group that are dispersed in an Epoxy resin or Silicone polymer, exhibiting RI˜1.7 or greater with a low value of optical absorption coefficient α<0.5 cm−1 at 525 nm. The encapsulant makes use of compositionally modified TiO₂ nanoparticles which impart a greater photodegradation resistance to the HRI encapsulant.

The invention belongs to the technical field of new energy materials and preparation thereof, and relates to a mesoporous graphite type carbon nitride/nitrogen doped graphene sol nanocomposite and a method for preparing the same. The method comprises the following steps that: graphene oxide and a surfactant are added into deionized water and are ultrasonically mixed uniformly to obtain a colloidal solution; mesoporous graphite type carbon nitride is added to be continuously and ultrasonically treated, and a nitrogen-containing compound is then added to be stirred at constant temperature to form a mixed solution; and hydrothermal reaction and natural cooling are then carried out, ammonia which is adsorbed to a material surface is removed through washing, and the material is dried. The yield of the prepared mesoporous graphite type carbon nitride/nitrogen doped graphene sol nanocomposite is high, and the mesoporous graphite type carbon nitride/nitrogen doped graphene sol nanocomposite has a wide application scope, can be applied to fuel cells, photodegradation reactors and the like. The method has the advantages of simplicity in technology, low cost, high yield, short period and environmental friendliness, and can be suitable for industrially producing the mesoporous graphite type carbon nitride/nitrogen doped graphene sol nanocomposite in a large scale.

Mixed-phase TiO₂ nanofibers prepared via a sol-gel technique followed by electrospinning and calcination are provided as photocatalysts. The calcination temperature is adjusted to control the rutile phase fraction in TiO₂ nanofibers relative to the anatase phase. Post-calcined TiO₂ nanofibers composed of 38 wt % rutile and 62 wt % anatase exhibited the highest initial rate constant of UV photocatalysis. This can be attributed to the combined influences of the fibers' specific surface areas and their phase compositions.

The invention discloses a preparation method and application of a ZnIn2S4-graphene composited photochemical catalyst. The preparation method comprises the following steps of: placing graphite oxide into a reducibility alcohol agent for ultrasonic dispersion; adding zinc sulfate and indium chloride into the reducibility alcohol agent, stirring and dissolving; adding thioacetamide into two systems after the two systems are mixed; transferring the mixed systems into a hydrothermal kettle for a reaction; and after the reaction is finished, carrying out vacuum filtration on the obtained product, washing, vacuumizing and grinding to obtain a nano ZnIn2S4-graphene composited photochemical catalyst. In the invention, grapheme is taken as a supporting material, and a solvothermal synthesis method is adopted to further prepare the nano ZnIn2S4-graphene composited photochemical catalyst. The catalyst prepared by using the method in the invention has the advantages of wide visible light responding range and high photocatalysis activity, can be used for transformation and use of solar energy and comprehensive ecological improvement, such as air purification, sewage disposal, hydrogen production through photodegradation, preparation of alcohol or hydrocarbon chemical fuels and the like by the photocatalysis and reduction of CO2.

Nitrogen doped TiO₂ (N—TiO₂) is used to fabricate Poly(vinylene fluoride) (PVDF)/N—TiO₂ mixed matrix hollow fiber membranes (HFMs) through a phase inversion method to improve filtration efficiencies and antifouling properties. The membranes performances were evaluated based on the water permeability, humic acid (HA) rejection and antifouling properties. Resulting membranes showed brown color and improved hydrophilicity, especially under light irradiation. When compared to original PVDF and PVDF/P25 membrane, mixed matrix membranes containing N—TiO₂ nanoparticles (NPs) showed clear photocatalytic activities under visible light irradiation. Also, membrane performance assessments indicated that PVDF/N—TiO₂ membranes possessed enhanced water flux, similar HA rejection (e.g., above 96%) and improved fouling resistance with PVDF membranes as a control. The results demonstrate the potential of the suggested methodology for development of membranes with improved water permeability and superior antifouling properties based on photo-degradation processes and photo-induced hydrophilicity enhancement driven by solar light as a renewable energy source.

The present invention relates to a double-degradation plastic film and its production method. Its raw material includes polythene, degradable starch, photodegradable additive, glycerine and ethylpropylene copolymer, the photodegradable additive can be any one of metal salt of N,N-dialkyl dithiocarbamic acid, titanium dioxide or calcium oxide. Said invention adopts the combination of photodegradation and biological degradation to imptement said invented degradation. Said film can be used for making various packaging bags.

The invention belongs to the technical field of films, and in particular relates to a photocatalytic inorganic nanoparticle/polydopamine/polymer self-cleaning composite film and a preparation method thereof. According to the preparation method, photocatalytic inorganic nanoparticles are modified to the surface of the composite film by using a chemical binding method, so that the stability of the inorganic nanoparticles on the surface of the composite film is improved, and the contact of the inorganic nanoparticles with pollutants is prompted so as to improve the photo-degradation efficiency of the inorganic nanoparticles, therefore, the self-cleaning capability of the composite film is improved. In addition, as polydopamine is used as a free group quencher, a polymer matrix is effectively prevented from being degraded when being affected by the photocatalytic inorganic nanoparticles in the UV (Ultraviolet) radiation process, so that the property stability of the composite film is improved, and the service life of the composite film is prolonged. The preparation method is simple in operation process, gentle in preparation condition, low in production cost and easy for in-batch and in-scale production, and has a good industrialization production basis and a wide application prospect.

The invention is directed to a photoresist-free method for depositing films composed of metals, such as copper or silica, or their oxides from metal complexes. More specifically, the method involves applying an amorphous film of a metal complex to a substrate. The metal complexes have a metal and a photo-degradable ligand. A preferred ligand is acac or alkyl-acac, expecially in combination with acetate ligands. These films, upon, for example, thermal, photochemical or electron beam irradiation may be converted to the metal or its oxides. By using either directed light or electron beams, this may lead to a patterned metal or metal oxide film in a single step. Low temperature baking may be used to remove residual organics from the deposited film. If silica is the metal, the deposited film has excellent smoothness and dielectric properties.

The invention discloses a noble metal orientation load titanium dioxide photocatalyst and a preparation method thereof. A titanium dioxide carrier has a rutile phase structure and a uniform spherical appearance, wherein the microsphere diameter is about 10 to 16 mu m; the surface is cracked; the titanium dioxide carrier is formed by self-assembling nanowires with the length of 5 to 8 mu m and diameter of 3 to 6 mu m; and the exposed surface of each nanowire is a crystal face (110). The noble metal is one or more of platinum, gold, ruthenium, rhodium, silver and palladium; the load quantity of the noble metal is 0 to 3 percent of the mass of the titanium dioxide carrier; the noble metal exists in the form of a zero-valence simple substance; the grain size of the noble metal is 2 to 10 nm; and the noble metal is orientationally deposited on the crystal face (110) of the titanium dioxide nanowires. The noble metal load titanium dioxide material serving as an effective photocatalyst is applied to light degradation of organic pollutants in a waste water solution.

The invention discloses a silver-modified bismuth tungstate composite photocatalyst, its preparation method and an application thereof. Bismuth tungstate in the catalyst is granules with the particle size being 0.5-3 microns and the catalyst is composed of bismuth tungstate pieces, the length of which is 30-100 nm and the thickness of which is 5-10 nm. Silver granules with the particle size being 5-40 nm are modified on the bismuth tungstate pieces. The specific surface area of the catalyst is 10-30 m<2>/g. The preparation method comprises the following steps of: respectively adding bismuth nitrate into a nitric acid solution with stirring to obtain a bismuth nitrate solution and adding polyvinylpyrrolidone into a sodium tungstate solution with stirring to obtain a mixed solution, adding the bismuth nitrate solution into the mixed solution, placing in an enclosed state, keeping warm at 160-180 DEG C for 20-24 h, centrifuging, washing, drying to obtain a bismuth tungstate powder, adding the bismuth tungstate powder into a silver nitrate solution, stirring, drying, grinding into a powder, and roasting the powder to prepare the target product. The product can be used in water polluted by organic matters or heavy metal ions to perform visible light photodegradation.

The invention discloses a degradable paper plastic composite bag including a plastic layer and a paper layer, the plastic layer is arranged on the surface of the paper layer, the plastic layer includes starch, vegetable fibre, polyvinyl alcohol, poly Beta-hydroxybutyrate, polyethylene, polycarbonate, nanometer titanium dioxide, glycerin, a plasticizer, and a stabilizing agent. The degradable paper plastic composite bag has excellent photodegradation and biodegradation properties, and is mild in degradation conditions and short in degradation time. The nanometer titanium dioxide in the plastic layer further improves the ultraviolet resistance capability of the plastic layer on the basis of having excellent degradability. In addition, the preparation method of the degradable paper plastic composite bag is simple in step and the degradable paper plastic composite bag can be produced industrially in batch because the raw materials are easy to get.

This invention relates to TiO2 photocatalysis materials preparation, particularly relates to a classification carbon-doped titanium dioxide catalyst material and preparation method. This invention is a kind of the carbon-doped titanium dioxide with mesoporous - macroporous grade pore structure, carbon 3-25%, anatase phase, the big channel pore size of 300-1000nm, mesoporous aperture 2.0-24nm, the specific surface area can be as high as 691m2/g. The described material is prepared by titanate and carbon mixture hydrolysis product of the roasting 300-600deg.C, and preparation of equipment used simple, the described materials in organic dye molecules have good catalytic properties on the photodegradation.

The invention belongs to the technical field of environmental-friendly inorganic nano materials and relates to a preparation method for synthesizing a N-TiO2@WSe2 photocatalyst through a sol-gel method and application of the N-TiO2@WSe2 photocatalyst. The preparation method comprises the following steps: preparing a titanium ethanol solution; dropwise adding a thiocarbamide ethanol solution; adding WSe2 and stirring uniformly; dropwise adding acidic ethanol water to obtain sol; aging, calcining at high temperature and grinding to obtain the N-TiO2@WSe2 photocatalyst. In the N-TiO2@WSe2 photocatalyst prepared by the method, N-TiO2 particles of about 50 nm are uniformly distributed on the surface of WSe2, so that the N-TiO2@WSe2 photocatalyst can be used for photodegradation of wastewater containing antibiotics. The dispersity of N-TiO2 is improved, the photocatalytic activity of N-TiO2@WSe2 is enhanced, and tetracycline degradation validates that the photocatalytic activity is 69.7% higher than that of unadulterated TiO2. The preparation method is simple, low in cost and high in controllability, the yield of products is high and environmental protection is achieved.

The invention provides a method for preparation of photo-catalytic nitrogen doped nano titanium oxide having visible light activity, belonging to the art of preparing titanium oxide powder. With directive thermal treatment, mix nano TiO2 powder, TiO2 colloid or Ti (OH) 4 with nitrogen source and water proportionally to prepare mixture suspension, mix around for among 0.5- 1h in among 10- 30Deg. C, dry for among 30- 90Deg. C, thermally treat for among 300- 650Deg. C and keep 0.5- 6h, then the anatase- type nitrogen doped nano titanium oxide powder is prepared. The merit is characterized in that: the property simulation of the prepared anatase- type nitrogen doped nano titanium oxide powder contains: measuring the phase constituent and the grain size number by X- ray diffraction, measuring light absorption by ultraviolet- visible light defuse reflection. measuring the absorption spectrum of photodegradation methyl blue solution with ultraviolet- visible light spectrophotometer.

The invention provides a method for preparing a solid waste composite multi-layer building formwork. The method comprises the following steps: wood powder, wood chips or sawdust and waste plastic are extruded and made into a wood plastic mixture which is used as an intermediate material of a product; the waste plastic and pulverized fuel ash are extruded and made into a plastic ash mixture which is used as a surface layer material of the product; and then a mold pressing or coextrusion method is adopted to obtain a novel composite board product with a wood plastic material as an intermediate layer and a plastic ash material as two outer layers. The compression strength of the prepared product can reach between 22 and 36MPa, the bending strength is between 15 and 28MPa, the bending modulus is between 450 and 980MPa, the breaking elongation rate is between 80 and 300 percent, the oxygen index is more than or equal to 25, the usage temperature is between 20 DEG C below zero and 55 DEG C, and the product has good mildew proofing, aging resistance, photodegradation resistance, wear resistance, corrosion resistance, and surface finish; and as a building formwork, the product can be repeatedly used for more than 20 times.

A method of fabricating visible light absorbed TiO₂/CNT photocatalysts and photocatalytic filters is disclosed, in which the method of fabricating the photocatalysts comprises steps: (a) providing a substrate; (b) forming a plurality of carbon nanotubes on the substrate; (c) providing a titanium source and an oxygen source; and (d) forming at least one titanium dioxide layer on the carbon nanotubes. The filter of the present invention comprises: a substrate, a plurality of carbon nanotubes, and a titanium dioxide layer. The plurality of carbon nanotubes form on the surface of the substrate, one end of each carbon nanotube connects to the substrate, and the titanium dioxide layer covers the surface of the carbon nanotubes. The filter of the present invention is a visible light absorbed filtering net, the titanium dioxide layer formed on the CNTs has high uniformity and therefore the photodegradation efficiency of the filter is an improvement.

The invention relates to a photocatalytic composite gel bead and a preparation method as well as an application of the gel bed. The composite bead takes crosslinked alginate as a matrix, and the matrix is filled with titanium dioxide nanometer particles. The preparation method specifically comprises the following steps of: firstly mixing the titanium dioxide, the alginate and water uniformly, dropwise adding the mixed solution into a calcium chloride solution by using an injector to prepare uniform beads, collecting and washing the beads, adding the washed beads into a solution of glutaraldehyde and hydrochloric acid to carry out a crosslinking reaction, and finally collecting and washing the beads to obtain the final product. The product has the advantages of low cost, simple preparation, good light degradation effect, easy separation and recycling and the like, has a good light degradation effect on hexavalent chromium, and can be applied to the treatment of chromium containing wastewater discharged from an electroplating factory, an electronic equipment factory, a metallurgical refinery and the like.

The invention belongs to the field of nano-materials, and discloses a preparation method of a reduced graphene oxide/bismuth vanadate/carbon nitride Z-type heterojunction composite photocatalyst. The preparation method includes the steps: performing thermal polymerization on urea to prepare graphite phase nitride carbon (g-C3N4); preparing graphene oxide by a Hummers method, and further preparing reduced graphene oxide; preparing a reduced graphene oxide/bismuth vanadate/carbon nitride composite material by a hydrothermal method. The utilization rate of visible light is improved by constructing Z-type heterojunctions, and photoelectric cavitation complex rate is reduced. The material can be used for photodegradation antibiotic pollutants and is of great significance for environmental control.

The invention relates to the field of biodegradable materials, in particular to a biodegradable material and a preparation method and application thereof. The biodegradable material at least comprises the following components in parts by weight: 100 parts of a carrier, 10-50 parts of a bio-based material, 5-20 parts of a compatilizer, 1-12 parts of a photodegradation agent, 5-20 parts of a filler and 0.01-5 parts of an aid, wherein the carrier is polyolefin resin; the bio-based material is any one or more of starch and natural plant fibers; the compatilizer is a mixture of glycidyl methacrylate and modified cyclodextrin, wherein the mass ratio of glycidyl methacrylate to modified cyclodextrin is 1:(0.1-1); the photodegradation agent is any one or more of anatase TiO2, a benzophenone compound, a transition metal compound or complex and rare earth carboxylate; and the aid is any one or more of an initiator, a plasticizer, a slipping agent, a dispersant and styrene.