702 results about "Octadecane" patented technology

The invention discloses a preparation method of a flexible material with double functions of radiation refrigeration and photothermal conversion storage, and relates to the field of composite phase change materials. The preparation method comprises the following steps: 1) preparing the flexible phase change material matrix by utilizing n-octadecane, SEBS and POE through hot pressing; 2) preparing a BaSO4 solution by using absolute ethyl alcohol, deionized water, a water-based defoaming agent, a water-based dispersing agent and an acrylic resin emulsion; (3) preparing an MXene solution; and 4) spraying the BaSO4 solution on the surface of one side of the flexible composite phase change material matrix by using a spray gun, and spraying the MXene solution on the surface of the other side of the flexible composite phase change material matrix to obtain the flexible composite phase change material. The radiation refrigeration layer can strongly reflect visible light and near-infrared light, has high emissivity in an infrared light area, especially in an atmospheric window wave band, reduces absorbed atmospheric heat radiation, reduces urban heat island effect caused by dense building groups in cities, and can effectively solve the problems of large day and night temperature difference and heat supply and demand in summer and winter.

The invention relates to the technical field of plugging agents, and discloses a viscoelastic polymer type self-assembly plugging agent and a preparation method thereof. The preparation method comprises the following steps: adding acrylamide, butyl acrylate, 2-acrylamide-2-methylpropanesulfonic acid, quaternized cyclodextrin, gamma-glycidyl ether oxypropyl trimethoxy silane modified bentonite, Schiff base styrene, a sodium dodecyl benzene sulfonate emulsifier and octadecyl dimethyl allyl ammonium chloride into a reaction kettle; and adding an azodiisobutyronitrile initiator into the deionized water, uniformly mixing, and reacting for 4-5 hours at 50-65 DEG C to obtain the viscoelastic polymer type self-assembled plugging agent after the reaction is finished. The plugging agent disclosed by the invention has a relatively good plugging effect, and effectively solves the problem that the gel strength is weakened or the gelling is not thorough due to the formation shearing effect in a continuous gel migration process.

The invention relates to the field of plastic bags, and discloses a biodegradable plastic bag and a preparation method thereof, the biodegradable plastic bag comprises polylactic acid, poly (butylene adipate-co-terephthalate), a functional additive, modified starch, a lubricant and an antioxidant; the functional additive is prepared by grafting hydroxylated modified castor oil and isocyanated montmorillonite loaded titanium dioxide; the hydroxylation modified castor oil is prepared by modifying castor oil with chloroethyl isocyanate, then reacting with N-allylimidazole, and then reacting with 6-mercaptohexyl-1-alcohol; the isocyanated montmorillonite loaded titanium dioxide is prepared by reacting montmorillonite loaded titanium dioxide obtained by a sol-gel method with isophorone diisocyanate; the modified starch is prepared by reacting octadecanoyl chloride and acryloyl chloride with starch, then carrying out graft copolymerization with ethyl acrylate and further introducing glycidyl methacrylate, so that the plastic bag is endowed with excellent mechanical properties, biodegradability and antibacterial property.

The invention provides a content detection method for a salvia miltiorrhiza medicinal material, a salvia miltiorrhiza clear paste and a musk heart-dredging dropping pill. According to the method, a high performance liquid chromatography method is adopted, octadecylsilane chemically bonded silica is used as a chromatographic column filler, acetonitrile is used as a mobile phase A, 0.02%-0.1% trifluoroacetic acid is used as a mobile phase B, gradient elution is carried out, and rosmarinic acid and salvianolic acid B in the salvia miltiorrhiza medicinal material are synchronously and quantitatively detected. And synchronously and quantitatively detecting tanshinol, protocatechuic aldehyde, caffeic acid, salvianolic acid E, rosmarinic acid, alkannic acid and salvianolic acid B in the salvia miltiorrhiza clear paste, and synchronously and quantitatively detecting tanshinol, protocatechuic aldehyde, caffeic acid, salvianolic acid E, rosmarinic acid, alkannic acid, salvianolic acid B, arenobufagin and bufalin in the musk Tongxin dropping pill. The method is used for monitoring the content of specific components, can also judge the transfer rate in the medicine production process, and facilitates traceability in the production link. In addition, the method is relatively low in equipment requirement and suitable for industrial popularization.

The invention discloses compression-resistant glass and a preparation method thereof, and relates to the technical field of special glass. When the compression-resistant glass is prepared, an anorthite crystal phase is used as a main material, a wollastonite crystal phase is used as an auxiliary material, and zinc, barium, boron, sodium, antimony and titanium elements are added, so that the compression-resistant glass ceramic is prepared; the preparation method comprises the following steps: mixing tetraethoxysilane, zirconium oxychloride octahydrate and 3-glycidyl ether oxypropyl trimethoxy silane, adding hydrochloric acid, and stirring to obtain modified sol; the preparation method comprises the following steps: mixing hydroxyl-terminated polysiloxane, trimethyl ethyoxyl silane, methyl triethyoxyl silane and octadecyl triethyoxyl silane, adding a hydrochloric acid solution, and reacting to prepare an organosilane modified solution; mixing the modified sol and the organosilane modified solution, coating the surface of the compression-resistant microcrystalline glass with the mixture, and curing to obtain the compression-resistant glass. The compressive glass prepared by the invention has the advantages of high compressive strength, hydrophobicity, wear resistance and high surface hardness.

The invention relates to the field of pharmaceutical analytical chemistry, in particular to a method for determining tandospirone and salt intermediates thereof, high performance liquid chromatography is adopted, and chromatographic conditions include that a chromatographic column with octadecylsilane chemically bonded silica as a filler is adopted, and gradient elution is performed by a mobile phase A and a mobile phase B; wherein the mobile phase A consists of a first water phase and acetonitrile; the mobile phase B is composed of a second water phase and acetonitrile; the first water phase is a water solution containing monopotassium phosphate and sodium hexanesulfonate, and the pH value of the first water phase is 3.0-3.8; the second water phase is an aqueous solution containing monopotassium phosphate and sodium hexanesulfonate, and the pH value of the second water phase is 1.8-2.6. The testing method disclosed by the invention has good specificity, accuracy and repeatability, and can be used for monitoring the quality of the tandospirone raw material medicine.

The invention belongs to the technical field of insulating oil, and provides a slow-release antioxidant as well as a preparation method and application thereof, the preparation method comprises the following steps: (1) mixing octadecyl trimethyl ammonium bromide, 2, 6-butylated hydroxytoluene, tetraethoxysilane, water and ammonia water, and reacting to obtain the antioxidant; and (2) in a protective atmosphere, mixing the antioxidant, ethanol, water and gamma-mercaptopropyltriethoxysilane, and carrying out a reaction so as to obtain the slow-release antioxidant. The slow-release antioxidant suitable for the synthetic ester insulating oil is prepared through a physical coating means and oleophylic modification, has excellent solubility, can effectively inhibit the increase of the acid value of the synthetic ester insulating oil, delays the oxidation process of the synthetic ester insulating oil, and remarkably prolongs the service life of the insulating oil. Meanwhile, through a slow release mechanism, the antioxidant can prolong the antioxidant effect of the antioxidant, improve the antioxidant stability in long-time operation and meet the higher antioxidant requirement of high-performance equipment such as a transformer for the insulating oil.

The invention discloses a carbon aerogel / reduced graphene oxide double-framework composite phase change material based on shaddock peel as well as a preparation method and application of the carbon aerogel / reduced graphene oxide double-framework composite phase change material. According to the method, the carbon aerogel / reduced graphene oxide double-framework material (CPA-rGO) with a hierarchical pore structure is constructed by taking waste shaddock peel as a raw material through freeze drying, a layer-by-layer self-assembly (LbL) technology and a gas-phase reduction and high-temperature carbonization process. And then, loading n-octacosane in the porous skeleton by a vacuum-assisted impregnation method to form the composite phase change material (OCPA-rGO) with a stable shape. The material has excellent leakproof performance (the leakage rate at 70 DEG C is only 4%), high thermal conductivity (0.366 W / (m.K)), remarkable photothermal conversion efficiency (91.6%) and electrothermal response characteristic, has a temperature sensitive resistance function, and can be applied to building energy-saving temperature control and intelligent household high-temperature early warning systems. According to the invention, high-value utilization of agricultural wastes is realized, and a new thought is provided for design of efficient and multifunctional phase change energy storage materials.

The invention provides a temperature-resistant and salt-resistant wall-fixing agent for a water-based drilling fluid for a myriameter deep well as well as a preparation method and application of the wall-fixing agent, and belongs to the technical field of drilling. The preparation method of the wall fixing agent comprises the following steps: adding acrylic acid into deionized water, adjusting the pH value of a system to 7.0, then sequentially adding N-hydroxymethyl acrylamide, N-[2-(3, 4-dihydroxyphenyl) ethyl]-2-acrylamide, an emulsifier, octadecyl vinyl ether and a complexing agent into the system, and shearing to obtain a monomer solution; adding an initiator into the monomer solution, and reacting; and after the reaction is completed, washing, drying and crushing to obtain the wall fixing agent. The wall fixing agent can resist the temperature of 200 DEG C, can resist the salt to be saturated, has strong adsorbability and high cohesion, and can effectively adsorb, block and bond micropores and micro cracks of rocks, so that the rocks are solidified, the well wall stability is effectively enhanced, drilling fluid leakage is prevented, and a technical guarantee is provided for safe and efficient drilling of deep wells.

The application belongs to the technical field of oil and gas field development, and provides a phase permeability improver, a fracturing fluid system containing the same, and respective preparation methods and applications. The phase permeability improver is obtained by copolymerization and hydrolysis of acrylamide AM, a functional monomer 2-acrylamido-2-methylpropanesulfonic acid AMPS, and cationic hydrophobic monomers A and B; the cationic hydrophobic monomer A is at least one of tetradecyl dimethyl allyl ammonium chloride, hexadecyl dimethyl allyl ammonium chloride, and octadecyl dimethyl allyl ammonium chloride; the cationic hydrophobic monomer B is at least one of methacryloyloxyethyl trimethyl ammonium chloride, acryloyloxyethyl trimethyl ammonium chloride, and acryloyloxyethyldimethyl benzyl ammonium chloride; the phase permeability improver and the fracturing fluid system containing the same can significantly reduce the water phase permeability after fracturing operation, while having a smaller influence on the oil phase permeability, and have a significant effect of stabilizing oil and controlling water, and can significantly improve the stable production effect of fracturing operation in a low-permeability oil reservoir.

The application provides a temperature-resistant and salt-resistant wall stabilizer for a ten-thousand-meter deep well water-based drilling fluid and a preparation method and application thereof, and belongs to the technical field of drilling. The preparation method of the wall stabilizer comprises the following steps: acrylic acid is added into deionized water, the pH of the system is adjusted to 7.0, then N-hydroxymethyl acrylamide, N-[2-(3,4-dihydroxyphenyl)ethyl]-2-acrylamide, an emulsifier, octadecyl vinyl ether and a complexing agent are sequentially added into the system, shearing is performed, a monomer solution is obtained, an initiator is added into the monomer solution, and reaction is performed; after the reaction is completed, washing, drying and crushing are performed, and the wall stabilizer is obtained. The wall stabilizer has a temperature resistance of 200 DEG C and a salt resistance of saturation, has strong adsorption and high cohesion, can effectively adsorb, plug and cement micro-pores and micro-cracks of rocks, thereby consolidating the rocks, effectively enhancing the well wall stability, preventing drilling fluid leakage and providing technical support for safe and efficient drilling of deep wells.

The invention discloses immobilized lipase based on bifunctional silicon dioxide as well as a preparation method and application of the immobilized lipase. Hydrophobic modification and covalent modification are performed on the surface of mesoporous silicon dioxide to obtain a bifunctional silicon dioxide carrier; the hydrophobic modification is any one of methylation modification, octylation modification, octadecyl alkylation modification, esterification modification and bromopropylation modification. The dual-functionalized silicon dioxide carrier is used for immobilization of lipase, and the prepared immobilized lipase can be used for production of biodiesel. The immobilized lipase provided by the invention is mild in enzyme reaction condition, good in biocompatibility, relatively high in enzyme activity, and excellent in stability and repeatability. In addition, by changing the ratio of the covalent modifier to the hydrophobic modifier, the catalytic activity and stability of the immobilized enzyme and the biodiesel yield are remarkably improved.

The invention relates to the field of plasma separation and detection, in particular to a composition for separating plasma and a using method thereof. The composition comprises: a phase change component, which is selected from n-alkanes, which are selected from at least one of n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane, n-eicosane, n-heneicosane or n-docosane; a liquid phase carrier component, wherein the liquid phase carrier component is selected from silicone oil; the structural framework and rheology regulation and control component comprises fumed silica, and the structural framework and rheology regulation and control component comprises fumed silica; the dispersion and stabilization auxiliary agent component is selected from at least one of TiO2 and BaSO4, the density adjusting filler component is selected from at least one of TiO2 and BaSO4, and the dispersion and stabilization auxiliary agent component comprises a silane coupling agent. According to the device, plasma and blood cells can be reliably, rapidly and effectively separated only through one-time low-temperature centrifugation, and remixing caused by transportation jolting can be avoided.

The invention discloses a method for detecting an intermediate acetylglucose of tetraacetyl by an HPLC-CAD (High Performance Liquid Chromatography-Computer Aided Design) method. The method comprises the following steps: (1) preparing a reference substance solution, namely dissolving acetylglucose by adding a diluent, and diluting to prepare the reference substance solution; (2) preparation of a test solution: taking tetraacetyl, adding a diluent solvent, and diluting to prepare the test solution; and (3) detecting the content of acetyl glucose in the test sample by adopting an HPLC-CAD (High Performance Liquid Chromatography-Computer Aided Design) method, and taking octadecylsilane chemically bonded silica as a filler in an adopted chromatographic column. According to the method disclosed by the invention, the intermediate acetyl glucose of the tetraacetyl substance is detected based on an HPLC-CAD (High Performance Liquid Chromatography-Computer Aided Design) method, and CAD parameters, a chromatographic column, a mobile phase, a diluent and a sample concentration are selected, so that the aims of effectively separating and accurately detecting the acetyl glucose in the sample can be fulfilled; the method has the advantages of simplicity, sensitivity, high accuracy, high repeatability, high specificity, good durability, high precision and the like, and has certain guiding significance on carbohydrate compound detection.

According to the all-organic nonlinear insulating material based on the electron-donating group and the preparation method, polyolefin is used as a matrix of the material, and an organic small molecule filler containing the electron-donating group is introduced to form a uniformly dispersed composite structure, so that the nonlinear conductivity of the material is remarkably improved. The small organic molecules can be ethylene glycol diphenyl ether, nonylphenol polyoxyethylene ether, allyloxy polyoxyethylene ether or octadecyl dimethyl hydroxyethyl quaternary ammonium nitrate, and the mass fraction of the filler is 0.1-3 wt%. The preparation method comprises the following steps: melting the polyolefin matrix at 110-120 DEG C, adding the small organic molecule filler, and blending for 10-30 minutes at the rotating speed of 50-70 r / min. The material has excellent electric field homogenization capability in a high electric field, avoids the problem of inorganic filler agglomeration, has relatively low filler content and excellent processability, can be widely applied to the field of high-voltage electrical equipment such as transformers, switch equipment and mutual inductors, and effectively improves the insulating property and prolongs the service life of the equipment.

The invention relates to the technical field of heat energy storage materials, and particularly provides a silicon dioxide aerogel composite phase change heat storage material and a preparation method thereof. The method comprises the following steps: mixing an organic silicon source, absolute ethyl alcohol and deionized water according to a specific ratio, fully stirring to obtain a mixed solution, and dropwise adding an acid catalyst into the mixed solution at room temperature for hydrolysis reaction to obtain a hydrolysate; sequentially adding a drying control agent and an alkali catalyst, and standing for gelation reaction to obtain gel; adding an organic solvent to carry out aging reaction, and then adopting the organic solvent to carry out replacement for multiple times to obtain alcogel; replacing the alcohol gel with an organic solvent for multiple times to obtain wet gel, soaking the wet gel in an excessive molten phase change material, and carrying out normal-pressure solvent replacement and drying at 40 DEG C to obtain the phase change material, the loading capacity of octadecane in the obtained CPCM is about 83%, the phase change enthalpy reaches up to 192J / g, the heat conductivity is as low as 0.0812 W / m.K, and no obvious leakage occurs after 200 times of circulation.

The invention relates to the technical field of chemical fiber manufacturing, in particular to a preparation process of graphene reinforced porous hollow polyester fibers. The problems that existing polyester fibers are insufficient in mechanical property and poor in moisture absorption and air permeability are solved. The preparation method comprises the following steps: modifying a PET sheet by using 2, 2-dimethylolpropionic acid and hydroxyl-terminated polydimethylsiloxane to obtain modified PET; the preparation method comprises the following steps: taking chitosan modified graphene as a carrier, and loading metal ions to obtain loaded graphene; polyethylene glycol and sodium bicarbonate are used as pore-foaming agents; modifying octadecyl dimethyl allyl ammonium chloride to obtain an antibacterial toughening agent; all the components are mixed, and the polyester fiber is prepared through melt spinning, stretching, heat treatment and alkali treatment. The mechanical property of the fiber is improved through the introduction of graphene and the modification treatment of the PET sheet; by utilizing the composite pore-foaming agent and adjusting the process, the moisture absorption and air permeability of the fiber are improved, and the service life of the fiber is prolonged.

The invention provides a specific chromatogram construction method and application of polygonum-folium isatidis formula granules. The specific chromatogram construction method comprises the following steps: acquiring a specific chromatogram of a to-be-detected substance by adopting a high performance liquid chromatography; the specific chromatographic conditions of the high performance liquid chromatography are provided, octadecylsilane chemically bonded silica is used as a chromatographic column of a filler, the detection wavelength is 305-315 nm, acetonitrile is used as a mobile phase A, a 0.04%-0.06% phosphoric acid aqueous solution is used as a mobile phase B, and elution is carried out according to a specific gradient program. The specificity of the material information corresponding to the characteristic peak in the characteristic spectrum obtained by the construction method is stronger, the related information in the characteristic spectrum represented by the method is more comprehensive, and the overall quality control of the polygonum-folium isatidis can be better realized.

The invention relates to a phase change energy storage fiber with ultraviolet shielding and heat regulation and control functions and a preparation method of the phase change energy storage fiber. The preparation method comprises the following steps: dissolving thermoplastic polyurethane in N, N-dimethylformamide to form a spinning mother solution; the preparation method comprises the following steps: firstly, adding nano titanium dioxide and uniformly dispersing, then adding a silicon dioxide shell layer-octadecane core layer phase change microcapsule, and stirring and ultrasonically defoaming to obtain a uniform composite spinning solution; extruding the spinning solution into a coagulating bath consisting of isopropanol and deionized water through an injection pump, and coagulating and forming to obtain nascent fibers; finally, washing, solvent replacement, tension setting and drying treatment are conducted, and compared with the prior art, the obtained fiber has efficient ultraviolet shielding performance and remarkable phase change energy storage capacity and has wide application prospects in the fields of intelligent temperature adjusting textiles, outdoor protective garments, building heat management and the like.

The invention discloses a phase change microcapsule and a preparation method of an epoxy resin self-repairing composite insulating material doped with the phase change microcapsule, the phase change microcapsule self-repairing epoxy resin composite material is of a core-shell structure, 500nm silicon carbide particles and octacosane are used as cores, and the outer layer is coated with Fe3O4 coated SiO2 nanoparticles. In the aspect of heat-conducting property, the heat-conducting property of the epoxy resin composite material is gradually increased along with the increase of the microcapsule content from 0 wt%. Due to the fact that microcapsules with Fe3O4 coated SiO2 nanoparticles as shells are added and interconnected to form a heat conduction network, the overall heat conduction performance of the material is improved; the microencapsulated repairing agent disclosed by the invention not only can heal cracks, but also can provide higher tensile property for damaged parts of the epoxy resin composite material.

The application provides an octadecane-loaded cellulose-based composite phase change material evaporator and a preparation method and application thereof in seawater desalination, and belongs to the fields of photo-thermal conversion materials and separation technologies. Nanocellulose and polyvinyl alcohol are mixed to prepare an aerogel, octadecane is encapsulated in the pores of the aerogel by a vacuum impregnation method to obtain a composite phase change material aerogel, and the composite phase change material aerogel is coated with a non-woven fabric loaded with polypyrrole to obtain the octadecane-loaded cellulose-based composite phase change material evaporator. The evaporator is a composite phase change material evaporator based on the coupling of interfacial evaporation and phase change energy storage, solves the problems of discontinuous evaporation and low solar energy utilization rate caused by day and night alternation, has excellent light absorption performance, good heat insulation performance and sufficient water supply and the like, can be used for seawater desalination, and has the advantages of high evaporation rate, high energy conversion efficiency, salt precipitation prevention and the like.

The invention discloses a salt-tolerant anti-calcium imbibition-oil displacement system suitable for a low-permeability compact oil reservoir and a preparation method thereof, the imbibition-oil displacement system comprises the following raw materials by weight: 0.05-1.5% of an amphiphilic head-based double hydrophobic chain surfactant, 0.05-1.5% of an amphiphilic head-based single hydrophobic chain surfactant, and the balance of water, wherein the double-hydrophilic-head-group double-hydrophobic-chain surface active agent is didecyl hydroxyl sulfonate, didodecyl hydroxyl sulfonate, ditetradecyl hydroxyl sulfonate or dihexadecyl hydroxyl sulfonate; the amphiphilic water head-based single hydrophobic chain surfactant is dodecyl amino acid salt, tetradecyl amino acid salt, hexadecyl amino acid salt or octadecyl amino acid salt. The imbibition-oil displacement system can be suitable for an oil reservoir formation water environment with low permeability, compactness, high total mineralization degree and high calcium ion content, can effectively reduce interfacial tension, and has imbibition-oil displacement performance.

The invention belongs to the technical field of traditional Chinese medicine detection, and specifically provides a characteristic spectrum of a gorgon fruit and a preparation thereof and a construction method thereof. In the construction method of the characteristic spectrum of the gorgon fruit and the preparation thereof, octadecylsilane bonded silica gel is used as a filler, an aqueous solution of formic acid-acetonitrile is used as a mobile phase, and gradient elution is performed. It is found that 9 common characteristic peaks can be obtained by using only 2 elution procedures, and good separation of these common characteristic peaks is achieved. The elution procedure is simple, the baseline of the obtained characteristic spectrum is stable, the noise interference is small, the characteristic peak shape is good, and the separation degree is high. The method can distinguish the gorgon fruit from its confusing products, provide a basis for the quality detection and control of the gorgon fruit and the preparation thereof, and achieve the characterization of the overall components of the gorgon fruit and the preparation thereof, with stable reproducibility.

The invention is suitable for the technical field of polyethylene pipeline materials, and provides a high-crack-resistance and high-durability medium-pressure polyethylene pipeline material and a preparation method thereof. Comprising the following components in parts by weight: 100 to 140 parts of medium-pressure polyethylene, 5 to 7 parts of tetra (octadecyloxy) phthalocyanine, 0.6 to 1.2 parts of a nucleating agent, 2 to 4 parts of nano silicon dioxide, 1.5 to 4.5 parts of montmorillonite, 1.3 to 2.7 parts of carbon black, 0.7 to 1.4 parts of a surfactant and 1.1 to 2.6 parts of a toughening agent. Preferably, the preparation method of the tetra (octadecyloxy) phthalocyanine comprises the following steps: adding tetrachloro phthalocyanine and octadecanol into a container according to a molar ratio of 1: 4, then adding a proper amount of K2CO3, taking DMF (Dimethyl Formamide) as a solvent, reacting under the protection of nitrogen, after the reaction is finished, adding ice water, filtering, and recrystallizing with methanol. The crack resistance and durability of the polyethylene pipeline material are remarkably improved, in addition, the preparation method is simple and easy to implement and easy for industrial production, and the prepared medium-pressure polyethylene pipeline material is low in cost and has a wide application prospect.

The invention relates to the technical field of super-hydrophobic anti-icing coatings, and discloses a photo-thermal super-hydrophobic anti-icing coating and a preparation method and application thereof.The photo-thermal super-hydrophobic anti-icing coating is prepared from nanocellulose, MXene, dopamine and octadecylamine, and the mass ratio of nanocellulose to MXene is (0.3-1.7): 1; the mass ratio of the dopamine to the MXene is 1: (0.3 to 1.7). A coating prepared from the photo-thermal super-hydrophobic anti-icing coating has good photo-thermal conversion capacity, has good compatibility with various substrates and can be applied to icing prevention in cold weather.

The invention mainly relates to a method for determining related substances of doxofylline injection, using high performance liquid chromatography, using octadecylsilane bonded silica gel as a filler; mobile phase A is a phosphoric acid aqueous solution with a pH of 1.5-3.5, and mobile phase B is acetonitrile, and gradient elution is performed. The detection method can completely separate impurities 1-9 in doxofylline injection, with a separation degree greater than 1.5, good system applicability, and the method has high specificity, accuracy and reproducibility, etc., is easy to operate, has no damage to the chromatographic column, and can be used for analysis, detection and quality control of doxofylline injection in industrial production.

The invention discloses a microcapsule phase change cement material, which is prepared by compounding a microcapsule with phase change performance and a cement matrix, the microcapsule is of a core-shell structure, the raw materials of the shell are melamine, urea and formaldehyde, the raw material of the core material is octadecane, and Tween 80 and lauryl sodium sulfate are used as emulsifiers. The preparation method comprises the following steps: 1, preparing an MUF resin prepolymer; 2, preparing a core material O / W emulsion; 3, polymerization reaction of the microcapsules; and 4, preparing the microcapsule phase change cement material. When the composite material is used as a cement-based composite material, the melting temperature ranges from 25 DEG C to 29 DEG C, the crystallization temperature ranges from 19 DEG C to 23 DEG C, the melting enthalpy ranges from 13.47 J / g to 29.78 J / g when the mixing amount is 10%-30%, the crystallization enthalpy ranges from 12.94 J / g to 28.41 J / g, and the coating efficiency is 67.5%. The initial decomposition temperature ranges from 386.13 DEG C to 390.96 DEG C, the finishing temperature ranges from 399.49 DEG C to 406.42 DEG C, and the maximum degradation temperature ranges from 438.78 DEG C to 443.64 DEG C; the heat conductivity coefficient is 0.3216 to 0.3949, and is improved by 39.4 percent compared with that of standard cement.

The invention relates to the technical field of chemical detection, and particularly discloses a method for detecting impurities in propafenone hydrochloride injection. The invention discloses a method for detecting impurities in propafenone hydrochloride injection, which comprises the following steps: detecting a sample to be detected by using high performance liquid chromatography to obtain the content of the impurities, in the detection process, octadecylsilane chemically bonded silica is used as a filling agent of a chromatographic column; the column temperature is 28-32 DEG C, and the flow velocity is 0.8-1.2 ml / min; the mobile phase comprises a mobile phase A and a mobile phase B, the mobile phase A is 0.012-0.017 mol / L dipotassium phosphate solution, and the pH value of the mobile phase A is adjusted to 2.2-2.8 with phosphoric acid; and the mobile phase B is acetonitrile. The detection method provided by the invention is simple to operate and high in detection speed, and has the advantages of high sensitivity, high precision, high repeatability and high accuracy.

The invention discloses a surface low-energy silicon dioxide shell phase change microcapsule, a moisture resistance control construction method and application thereof. Firstly, core-shell structure microcapsules with octadecane as a heat energy storage core material and silicon dioxide as a protective shell layer are prepared through an interfacial polymerization method, and phase change microcapsule powder is obtained. And then, constructing an alkylated low-energy interface layer on the surface of the microcapsule shell by utilizing an organosilane hydrolysis-condensation reaction. The phase change microcapsule treated by the method can effectively inhibit a shell layer from adsorbing free moisture in a humid environment, alleviate the phenomenon of interface instability at the initial stage of cement hydration, and improve the construction fluidity and circulating energy storage durability of a cement-based material. Meanwhile, the composite can be used as functional microparticles to be applied to building outer surface coatings, and antifouling, anti-infiltration and photo-thermal regulation and control effects are achieved. The method is simple, convenient and high in adaptability, large-scale production can be achieved, and a new solution is provided for construction of building functional materials with energy conservation, energy storage and interface stability.

The invention relates to the technical field of biochemical engineering, in particular to a method for extracting high-purity Ectoine from Ectoine mother liquor. According to the method, the Ectoine mother liquor is purified into high-purity Ectoine solid through the steps of chromatographic separation, ion exchange process, concentration and decoloration and crystallization in sequence; chromatographic separation adopts a specific filler (silica gel bonded octadecylsilane (C18) or a strong cation exchange resin filler), and separation is carried out at room temperature by controlling the sample size and the flow rate; in the ion exchange process, strong-acid cation exchange resin and strong-base anion exchange resin are connected in series to remove cation and anion impurities; concentrating and decoloring through vacuum concentration and activated carbon decoloring; and adding low-molecular alcohol for cooling crystallization, and carrying out spinning filtration and drying to obtain high-purity Ectoine solid. According to the method, the purity of Ectoin can reach 99% or above, and the method has the advantages of being low in cost, environmentally friendly and suitable for large-scale industrial production.