1250 results about "Chemical modification" patented technology

The invention provides a polyaniline / modified graphene oxide composite material and a preparation method thereof. The preparation method comprises the following steps: dispersing purified graphene oxide, performing ultrasonic treatment, heating, adding a modifier for modification, centrifuging, taking precipitate, freezing, drying and grinding to obtain modified graphene oxide powder; mixing the powder with an aniline solution in doped acid to form a modified graphene oxide / aniline acid solution; dissolving ammonium persulfate in the doped acid to prepare an ammonium persulfate acid solution; and slowly dropwise adding the solution into the solution, carrying out in-situ polymerization, and carrying out suction filtration, washing and drying to obtain the composite material. According to the method, through chemical modification and in-situ polymerization processes, the problems that a single filler is poor in dispersity, a conductive network is discontinuous, and anti-corrosion and anti-static performance is difficult to synergistically improve are solved, and the process is simple and convenient and suitable for industrialization.

The invention relates to a high-strength stable solid waste-based composite cementing material and a preparation method and application thereof in the field of building materials. The high-strength stable solid waste-based composite cementing material is prepared from the following raw materials in parts by weight: 70-85 parts of composite solid waste micro powder; 10 to 20 parts of Portland cement clinker; 3-8 parts of a composite activator; 0.5 to 2 parts of a nano-scale function regulator; wherein the composite solid waste micro powder is prepared by mixing and grinding the following raw materials in parts by weight: 40-60 parts of blast furnace slag powder; 20 to 30 parts of fly ash; 10-20 parts of chemically modified electrolytic manganese residue powder; and 5-15 parts of steel slag powder. According to the preparation method, sodium metasilicate is adopted to assist medium-temperature calcination to chemically modify the electrolytic manganese residues, so that not only is the gelation activity of the electrolytic manganese residues effectively excited, but also free-state manganese, cadmium and other heavy metal ions in the electrolytic manganese residues are fixed in situ in newly formed zeolite-like silicate mineral lattices through thermochemical reconstruction; and a brand new technical path is opened up for safe and high-value utilization of the typical hazardous waste, namely the electrolytic manganese residues.

Among other things, the present disclosure provides oligonucleotide compositions and methods thereof. In some embodiments, oligonucleotides comprise various chemical modifications. In some embodiments, the present disclosure provides technologies useful for manufacturing oligonucleotides.

The invention belongs to the technical field of organic matter preparation, and discloses an amide-containing isoxazoline derivative as well as a preparation method and application thereof. According to the invention, chemical modification and molecular design are carried out on the compound with an isoxazoline structure, and a substituent group is introduced to N of an amide group, so that a series of efficient compounds which can be used for killing insects or mites in agriculture or forestry and have excellent activity are obtained, and particularly, the compounds have very good biological activity on lepidoptera, hemiptera and other pests. When being used at an extremely low concentration, the compound disclosed by the invention also shows an excellent control effect on various pests or pest mites, has insecticidal or acaricidal activity in each stage (such as eggs, larvae (nymphs), pupae and adults) of the life cycle of the pests or pest mites, and has an excellent control effect on the pests or pest mites which have drug resistance to traditional insecticides or acaricides. And the composition also shows excellent control activity.

The present disclosure features useful oligonucleotide compositions and methods related thereto. The present disclosure encompasses the recognition that structural elements of oligonucleotides, such as base sequence, chemical modifications (e.g. modifications of sugar, base and / or internucleotide linkages) or patterns thereof, can have a significant impact on oligonucleotide properties and activities. The present disclosure also provides methods to treat disorders for which deamination of an adenosine in an mRNA produces a therapeutic result, e.g., in a subject in need thereof.

The invention relates to a laser processing method for a coated armor structure of wear-resistant super-hydrophobic aluminum bronze, which comprises the following steps of: preparing an aluminum bronze workpiece, polishing and cleaning, depositing a ceramic wear-resistant film on the surface of the workpiece by adopting pulse laser, and etching the ceramic wear-resistant film by adopting femtosecond laser, so as to obtain a coated armor structure of the wear-resistant super-hydrophobic aluminum bronze. And then chemical modification of the wear-resistant armor structure is completed through heat treatment, chemical modification of the micro-nano surface structure is completed, and the wear-resistant super-hydrophobic aluminum bronze is obtained. The wear-resistant ceramic film and the wear-resistant armor structure can resist wear together, double guarantee is provided for the internal hydrophobic microstructure, the super-hydrophobic wear resistance of the surface of a component in underwater equipment can be improved, the service life of the component can be prolonged, and the problem of marine organism corrosion is solved.

A method for visible light-mediated chemical modification of a polypeptide or protein based on cysteine includes the following steps: allowing a cysteine residue on a cysteine-containing oligopeptide, polypeptide, or protein to undergo a reaction with an activating reagent to generate a free radical precursor in situ; and subjecting the free radical precursor to desulfurization under photocatalytic condition, and allowing the generated free radical intermediate to undergo an addition reaction with an olefin or an alkyne, such that sulfhydryl removal and carbon-carbon bond construction are achieved to produce a chemical modification product of the polypeptide and protein. The method cleverly avoids the influence on the chiral center, and thus the chirality of the amino acid residue can be retained. The method is conducive to well avoiding the occurrence of side reactions, and thus the efficiency of the entire conversion is very high.

The invention discloses a silane cross-linked polyolefin halogen-free flame-retardant cable material and a low-energy-consumption preparation method thereof.The preparation method comprises the steps that EVA / EEA serves as a matrix, silane groups are covalently connected to a polyolefin molecular chain through a free radical grafting reaction, and a grafting material containing an active silane side group is prepared; meanwhile, vinyl isocyanate is adopted to chemically modify hydroxyl on the surface of magnesium hydroxide, vinyl is grafted to the surfaces of particles, the polarity of the particles is reduced, and the dispersity of the particles is enhanced; then carrying out melt blending on the grafted material and modified magnesium hydroxide, constructing an interface bridge by using an anhydride group, and shortening the two-phase distance; finally, through room-temperature natural cross-linking and warm water auxiliary cross-linking, silane groups are promoted to be hydrolyzed into silanol, the silanol is condensed to form a-Si-O-Si-three-dimensional network, meanwhile, vinyl on the surface of magnesium hydroxide and a polyolefin matrix are subjected to free radical copolymerization, and a covalent bond interface layer is formed between inorganic particles and an organic matrix. According to the method, the synergistic improvement of high crosslinking degree, strong stretchability and excellent flame retardance of the cable material is realized through molecular-level interface regulation and cross-linking network optimization.

The invention relates to the technical field of high-temperature-resistant and high-thermal-conductivity epoxy electronic packaging adhesives, discloses a preparation method of a core-shell Al2O3-coated SiO2 filler and application of the core-shell Al2O3-coated SiO2 filler in epoxy packaging, and designs the preparation method of the core-shell structure filler Al2O3-coated SiO2 by chemically modifying the surface of the Al2O3 filler through high-temperature-resistant SiO2. The high-temperature-resistant SiO2 shell layer is modified on the surface of Al2O3, so that the interface wettability between the epoxy resin and the filler is promoted, the binding force between the filler and the epoxy resin is increased, the dispersity and fluidity of EMC are improved, meanwhile, the 175-DEG C bending strength of the epoxy resin is improved, and the high-temperature usability of the epoxy resin is greatly improved. And finally, the core-shell structure Al2O3-coated SiO2 can easily form a heat-conducting path among the filler, the interface and the matrix resin, so that the overall heat-conducting property of the composite material is improved, the low thermal expansion coefficient of the SiO2 shell layer is improved, the thermal stress is buffered, the temperature resistance is improved, and the core-shell structure Al2O3-coated SiO2 can be widely applied to packaging of semiconductor integrated circuits.

The invention discloses an information storage method based on DNA (deoxyribonucleic acid) coding, which comprises the following steps: converting digital information to be stored into a quaternary code, converting the quaternary code into a DNA sequence consisting of adenine A, cytosine C, guanine G and thymine T according to a preset mapping rule, and expressing an additional information dimension by using a chemical modification state of a nucleotide pair; inserting error detection and correction codes in the DNA sequence every a predetermined number of basic group positions, segmenting the encoded DNA sequence into a plurality of fragments with the length of 100-150bp, and adding a specific recognition sequence and an index marker at two ends of each fragment; a reversible thermosensitive response DNA nanostructure is used as a carrier, DNA fragments are selectively combined to the carrier, and hierarchical storage and rapid retrieval of information are realized through a temperature gradient control system; the DNA storage information density can be remarkably improved, the service life of DNA storage can be remarkably prolonged, and a novel technical path is provided for large-scale, long-term and safe molecular information storage.

The invention belongs to the technical field of polyurethane waterproof coatings, and particularly relates to a single-component fluorine-free high-hydrophobicity polyurethane waterproof coating and a preparation method thereof, and the single-component fluorine-free high-hydrophobicity polyurethane waterproof coating comprises the following raw materials by weight: 60-80 parts of composite polyether polyol; 20 to 40 parts of silane modified polyether polyol; 11 to 17 parts of diisocyanate; 2-5 parts of a chain extender; 50 to 70 parts of a plasticizer; 50 to 70 parts of filler; 0.15 to 0.2 part of a catalyst; and 3-5 parts of an auxiliary agent. A polyoxypentene ether chain segment, a castor oil-based structure and a silane group are introduced into the molecular structure of the waterproof coating through chemical modification, the intrinsic hydrophobic and mechanical properties of the material are improved, the migration defect caused by addition of a hydrophobic agent and silicone oil in a traditional preparation method is overcome, and the invention further provides a preparation method of the waterproof coating.

The invention belongs to the technical field of novel adsorption materials, and particularly relates to needle-punched cloth for extracting uranium from seawater based on dry-process PAN fibers and a preparation method and application of the needle-punched cloth. The needle-punched fabric for extracting uranium from seawater comprises chemical modified functional fibers and supporting fibers, the chemically modified functional fiber with amidoxime groups is obtained by chemically modifying a dry polyacrylonitrile short fiber. The invention discloses the needle punched cloth for extracting uranium from seawater based on the dry PAN fiber for the first time, the material has the advantages of low production cost, batch production and large-scale implementation, can be directly soaked in seawater, can be rolled into components such as a filter element and the like, and can be used for enriching and separating uranium from seawater in forms of single-layer filtration, multi-stage filtration and the like; the industrial popularization and application are easy.

The invention belongs to the field of oilfield chemistry, and discloses development and a method of a gel breaker for recycling drilling fluid, and the preparation method comprises the following steps: (1) contacting chitosan with a modifier under an alkaline condition for chemical modification to obtain O-carboxymethyl chitosan; and (2) carrying out radical polymerization on the obtained O-carboxymethyl chitosan and a quaternary ammonium salt monomer in an acid environment under the action of an initiator to obtain the gel breaker.

The invention belongs to the technical field of biological medicine, and discloses fluorine-containing modified poly-sarcosine acidified lipid as well as a preparation method and application thereof. The fluorine-containing modified poly-sarcosine acidified lipid disclosed by the invention has a structural general formula as shown in a formula (I) or a formula (II). The fluorine-containing modified poly-sarcosine acidified lipid obtained by chemically modifying the poly-sarcosine acidified lipid through different fluorine-containing groups can replace PEGylated lipid to prepare lipid nanoparticles (LNP), and is used for loading drugs such as nucleic acid and the like, so that the purpose of improving the drug delivery performance is achieved.

To provide a pressure-sensitive adhesive sheet capable of suppressing heavy peeling even when using an aqueous pressure-sensitive adhesive composition.SOLUTION: A pressure-sensitive adhesive sheet according to an embodiment of the present invention includes: a base material; and a pressure-sensitive adhesive layer formed of a water-dispersible pressure-sensitive adhesive composition containing a water-dispersible polymer, wherein a surface concentration of a carboxyl group on a surface of the pressure-sensitive adhesive layer obtained by an X-ray photoelectron spectroscopy (ESCA) gas phase chemical modification method is a detection limit value or less.SELECTED DRAWING: Figure 1

The invention relates to the technical field of material surface engineering, and discloses a plastic surface treatment process to solve the problems that in the prior art, a plastic surface coating is poor in adhesive force and single in function, and a traditional treatment method is not environmentally friendly. The process sequentially comprises the following steps: pre-treating a base material, and obtaining a clean and stress-free base material through ultrasonic cleaning and thermodynamic stress elimination; performing low-temperature plasma surface activation, performing physical bombardment and chemical modification on the plastic surface by utilizing plasma of specific process gas in a vacuum environment, introducing a large number of active functional groups, and remarkably improving the surface energy; and preparing and applying the functional nano coating, namely forming firm covalent bonds by using the coupling agent in a coating solution containing functional nano particles and a coupling agent and the anchor points, so that the chemical coupling of the functional coating and the plastic substrate is realized.

The invention provides an ultralow-swelling artificial cornea imitating natural cornea fiber arrangement and a preparation method, and belongs to the technical field of biomedical materials.The preparation method comprises the steps that I-type collagen is dissolved in a PBS buffer solution, a photofunctionalization modified active reagent is added for chemical modification, stirring is conducted in a dark place, freeze drying is conducted, and photofunctionalization collagen is obtained; dissolving the photo-functionalized collagen, and then preparing a collagen fiber membrane through electrostatic spinning; and performing phase change DLP 3D biological printing on the biological ink and the collagenous fiber membrane to obtain the keratoprosthesis with the collagenous fiber sandwich structure. Multi-layer arrangement is achieved through DLP 3D biological printing, the fiber trend of the natural cornea is simulated, and the mechanical anisotropy is remarkably improved; through a composite phase change DLP 3D printing mode of GelMA / HA-DN and photo-crosslinking collagenous fibers, the composite phase change DLP 3D printing material has good manufacturability, maintains high light transmittance and maintains high mechanical strength.

The invention discloses a method for preparing micro-nano fibers through needle-free electrostatic spinning equipment assisted by an ion blower gun, and belongs to the technical field of spinning. The method specifically comprises the following steps: S1, dissolving a high-molecular polymer in a proper solvent to prepare a spinning precursor solution; and S2, preparing the micro-nano fiber from the spinning solution on a suitable collection surface by using an ion blower gun assisted needleless electrostatic spinning device. Through the synergistic effect of directional airflow generated by the ion blower gun and a controllable electric field, fiber surface charges are effectively neutralized, the jet instability is inhibited, and the controllability of a fiber flight path is improved. Meanwhile, the ionic wind assists in enhancing interface attachment between the fiber and the collector, uniform deposition is promoted, and the compactness and adhesive force of the fiber membrane are remarkably improved. According to the method, chemical modification does not need to be carried out on a material system, the intrinsic performance of the fiber is kept, universality and expandability are achieved, and a new path is provided for continuous preparation of the high-performance micro-nano fiber.

The invention discloses a controllable degradation antibacterial filament fiber and a preparation method thereof, a calcium alginate filament fiber is prepared by using a wet spinning technology, and the calcium alginate filament fiber is strongly modified by physical and chemical methods respectively. The chemical modification adopts a cross-linking agent for modification, and the physical modification adopts cellulose nanocrystal (CNC) as a reinforcing material. The tensile breaking strength is improved to 43.25 cN / dtex from 16.35 cN / dtex which is not modified, the tensile breaking strength is improved by 2.6 times, and the degradation period is prolonged to 7 days from 2 days. On the basis, berberine is introduced into the fiber, so that the mechanical enhancement effect can be further achieved by means of the electrostatic attraction effect between materials, the antibacterial performance is obtained, and the antibacterial rate can reach 95.28%.

The invention discloses a modification method and application of recycled concrete aggregate. The modification method comprises the following steps: pretreatment, physical modification, chemical modification and surface enhancement treatment. The waste concrete is efficiently recycled, the pollution of construction waste to the environment is reduced, the exploitation amount of natural aggregate is reduced, and natural resources are protected; meanwhile, a physical, chemical and surface enhancement treatment synergistic modification mode is adopted, and modification steps are mutually matched and promoted; physical modification creates good surface conditions for chemical modification, chemical modification further optimizes the surface components and structure of the aggregate, surface enhancement treatment finally improves the surface performance of the aggregate, various problems existing in the recycled aggregate are effectively solved, and the comprehensive performance of the recycled aggregate is comprehensively improved; the application range of the building material in building engineering is expanded, the cost of the building material is reduced, and the building material has remarkable economic benefits and environmental benefits.

The invention discloses a nano ardealite-based saline-alkali soil modifier and a preparation method thereof, and relates to the technical field of soil improvement, the method comprises the following steps: uniformly mixing humic acid, charcoal and a halophilic microbial agent, and then fermenting at 28-32 DEG C for 115-125 hours to obtain a fermentation system; the preparation method comprises the following steps: grinding ardealite into nano ardealite, dispersing the nano ardealite under the action of a surfactant and deionized water, and carrying out surface etching by using acid to form microdot vacancies on the surface of the nano ardealite, so as to obtain chemically modified nano ardealite; the nano phosphogypsum-based saline-alkali soil modifier is obtained by uniformly mixing the chemically modified nano phosphogypsum with a fermentation system, has the advantages of multiple effects, low cost and environmental friendliness, can significantly reduce the salinity and alkalinity of soil, improve the soil structure and promote the growth of crops, realizes the resource utilization of the phosphogypsum, and reduces the environmental pollution.

The invention provides a ring-opening polymerization method of N-carboxyl intracyclic anhydride, which comprises the following step: by taking N-carboxyl intracyclic anhydride as a monomer and taking dendritic macromolecular polyamide-amine (PAMAM) as an initiator, carrying out ring-opening polymerization reaction to obtain an amino acid polymer. According to the technical scheme provided by the invention, beta-folding of N-carboxyl intracyclic anhydride monomers (including N-carboxyl intracyclic anhydride with beta-folding tendency) during ring opening polymerization can be effectively avoided, and a product with alpha-helical configuration is obtained. Therefore, the reaction rate of ring-opening polymerization of the N-carboxyl anhydride is obviously accelerated; the molecular weight of the formed polymer is controllable, and the molecular weight distribution is more uniform; the strategy of irreversible chemical modification on the N-carboxyl intracyclic anhydride monomer is avoided, and the chemical nature of the N-carboxyl intracyclic anhydride residue is retained to the greatest extent; the whole reaction process is simple, monomer raw materials are easy to obtain, and the method is very suitable for large-scale popularization and application.

The invention relates to a method for preparing a cement admixture resistant to mine water erosion by microwave synergistic chemical modification of fly ash, and belongs to the technical field of industrial solid waste recycling and building materials.According to the method, fly ash particles are mechanically activated and crushed, and a composite modifier treatment and gradient microwave activation technology is combined, so that the cement admixture resistant to mine water erosion is prepared; the activity of the fly ash and the erosion resistance of the cement-based material are obviously improved. The preparation process comprises the following steps: carrying out multi-stage mechanical grinding on the fly ash to obtain ultrafine powder; adding a composite modifier containing a mineral active component, an organic-inorganic composite modifier and a nano functional material for chemical activation; microwave irradiation and nitrogen quenching are adopted to cooperatively process and reconstruct the microstructure of the material; and finally forming through a microwave-steam coupling curing process. The obtained cement admixture can effectively solidify corrosive ions in mine water, improve the durability of traditional cement in a complex ion environment, and realize bulk resource utilization of fly ash solid waste.

The embodiment of the invention provides a connecting unit for chemical modification of a nucleic acid end group, a preparation method of the connecting unit and a nucleic acid probe. The connecting unit for chemical modification of the nucleic acid end group has a triethylene glycol structure, and the connecting unit has the following structure. Therefore, the connecting unit with the triethylene glycol structure is relatively simple in synthesis process, relatively high in yield, efficient in synthesis, good in nucleic acid end group chemical modification effect, applicable to connection of various types of probe molecules and nucleic acid molecules, capable of simply and efficiently preparing nucleic acid probes and wide in application range.

The invention relates to the technical field of solar cells, in particular to a perovskite cell, a preparation method of the perovskite cell, a laminated cell and a photovoltaic module. Electron-rich N atoms in dithienopyrrole (DTP) can improve the stability of an organic semiconductor material in an oxidation state, S atoms can interact with metal ions in a perovskite absorption layer, so that interface defects on the surface of perovskite are passivated, and meanwhile, DTP serves as a multifunctional electron-rich thiophene fused heterocyclic unit, so that the performance of the perovskite absorption layer is improved. The compound has the unique characteristics that the recombination energy is small, the mobility is high, N and thiophene sites can be chemically modified, and the compound can interact with metal ions. According to the invention, thiophene sites in DTP are chemically modified by adopting an electron-donating group containing aniline fluorene, so that the hole transport material has a deeper HOMO energy level, the HOMO energy level is better matched with the energy level of a perovskite material, better mobility is realized, and hole extraction and transport are facilitated.

The invention belongs to the technical field of chemical modification of natural polymer materials, and particularly relates to a modified cellulose adhesive and a preparation method thereof. The modified cellulose adhesive is prepared from the following components in parts by weight: 50 to 70 parts of modified cellulose-based emulsion, 10 to 20 parts of VAE (Vinyl Acetate Ethylene) composite emulsion, 5 to 8 parts of rosin water emulsion, 3 to 8 parts of cross-linking agent and 2 to 5 parts of plasticizer, the modified cellulose is obtained by grafting an epoxy hypophosphite compound and a fluorine-containing pentaphenyl alkynyl dicarboxylic acid compound with a nano cellulose solution; according to the prepared modified cellulose adhesive, targeted improvement of waterproofness, durability and bonding strength is achieved through molecular design.

The present invention belongs to the technical field of oils for hydraulic supports and provides a biodegradable natural plant-extracted emulsified oil for hydraulic supports and a preparation method thereof. First, through multi-step chemical modification of palm oil, including epoxidation, boronation, phosphating, and block polymerization, the epoxidation reaction introduces epoxy groups, increasing the reactivity of the oil; the boronation and phosphating reactions further enhance the polarity of the oil and its ability to form a lubricating film; and through block polymerization with caprolactone, the stability and wear resistance of the lubricating film are enhanced. Second, through carboxymethylation of chitosan, the carboxyl groups in the carboxymethyl chitosan react with oxides on the metal surface to form a chemical passivation protective film; and the sulfonic acid groups in the sodium lignosulfonate bind to the metal surface through electrostatic adsorption, further forming a protective layer. The synergistic effect of the two forms a multi-layer dense protective film on the metal surface, significantly improving the anti-corrosion performance of the emulsified oil.

The invention provides a diamine monomer based on a benzoaromatic heterocyclic structure, polyimide and a preparation method, and belongs to the technical field of polymer-based functional materials. The diamine monomer based on the benzoaromatic heterocyclic structure has a structure # imgabs0 # as shown in a formula I, R is-S-,-O-,-NH,-NPh or-N-iPr, and R1 is-H,-CF3 or-CH3. And polymerizing the diamine monomer and the dianhydride monomer to obtain polyimide. The heteroatoms are introduced into the prepared polyimide structure, so that stronger chemical bonds and intermolecular forces can be formed, the thermal stability, mechanical properties and solubility of the PI film are improved, meanwhile, the structure also has more chemical modification sites, and the properties of the PI film can be further improved by introducing different groups at different positions.

The present disclosure provides double stranded oligonucleotides, compositions, and methods relating thereto. The present disclosure encompasses the recognition that structural elements of double stranded oligonucleotides, such as base sequence, chemical modifications (e.g., modifications of sugar, base, and / or internucleotidic linkages) or patterns thereof, and / or stereochemistry (e.g., stereochemistry of backbone chiral centers (chiral internucleotidic linkages), and / or patterns thereof, can have significant impact on oligonucleotide properties and activities, e.g., RNA interference (RNAi) activity, Ago2 loading, thermal stability, in vivo stability, delivery to tissues and into cells, etc. The present disclosure also provides methods for treatment of diseases, e.g., hepatic diseases, central nervous system (CNS) diseases, etc., using provided double stranded oligonucleotide compositions, for example, in RNA interference.

The invention provides an influenza vaccine adjuvant based on lentinan as well as a preparation method and application thereof. The active ingredient of the vaccine adjuvant is lentinan, the lentinan is extracted from fresh lentinus edodes through a water extraction and alcohol precipitation method, no additional chemical modification is needed, the vaccine adjuvant can be used for preparing the influenza virus vaccine, and the influenza virus vaccine at least contains one of three inactivated influenza virus antigens, namely H1N1 A, H3N2 A and Victoria B. The invention also provides a vaccine preparation and a preparation method thereof, the vaccine preparation comprises the vaccine adjuvant and an influenza virus vaccine, the content of lentinan in the vaccine preparation is 4 mg / mL, and the vaccine preparation has an immunological enhancement effect.