7504 results about "Ethyl group" patented technology

Provided is a copolymer comprising tetrafluoroethylene unit and perfluoro(ethyl vinyl ether) unit, wherein the copolymer has a content of perfluoro(ethyl vinyl ether) unit of 4.5 to 6.2% by mass with respect to the whole of the monomer units, a melt flow rate at 372° C. of 0.8 to 4.0 g / 10 min, and the number of functional groups of 20 or less per 106 main-chain carbon atoms.

The invention discloses a preparation method of a fluorine-containing carbazole phosphonic acid compound, which solves the technical problems of harsh reaction conditions, high raw material price and low yield in the existing preparation process, 4-trifluoromethoxyaniline and 4-trifluoromethoxyiodobenzene are used as initial raw materials, and Ullmann reaction is performed under a solvent-free condition to obtain 4, 4 '-difluorocarbazole phosphonic acid. The preparation method comprises the following steps: taking 3, 4 '-bis (trifluoromethoxy) diphenylamine as a raw material, carrying out palladium acetate catalytic oxidation cyclization to obtain 3, 6-bis (trifluoromethoxy) carbazole, reacting the 3, 6-bis (trifluoromethoxy) carbazole with 2-bromoethyl dimethyl phosphonate to obtain N-(2-ethyl dimethyl phosphonate) 3, 6-bis (trifluoromethoxy) carbazole, and finally hydrolyzing to obtain the N-(2-ethyl phosphonate) 3, 6-bis (trifluoromethoxy) carbazole. The reaction process is simpler to operate, the yield is guaranteed, and the method is suitable for large-scale production. In the preparation method disclosed by the invention, a solvent is not required to be used in multiple steps, the reaction is performed under a solvent-free condition, and the preparation method is high in safety and environment-friendly.

The invention provides a polymer additive and application thereof. The polymer additive is prepared from the following components in parts by mass: 30 to 90 parts of diethyl phosphinate, 0.01 to 3 parts of ethyl phosphonate, 5 to 67 parts of dialkyl phosphinate and 0.01 to 5.5 parts of alkyl phosphinate. The dialkyl phosphinate has a structure as shown in a formula I, and the alkyl phosphinate has a structure as shown in a formula II. According to the invention, through design and compounding synergy of various phosphonates, the flame-retardant effect can be obviously improved, so that the polymer additive has excellent and efficient flame retardance. The polymer additive is used in a polymer material, and a polymer composition containing the polymer additive can have excellent flame retardant property, good toughness, high impact strength and excellent mechanical property and humidity and heat resistance under the condition that the addition amount is small.

The application provides a process method for preparing (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl) phosphonic acid, and particularly relates to the technical field of organic synthesis. The process method is that, under alkaline conditions, a halogenated phosphonate compound is added into a 3,6-dimethoxy-9H-carbazole solution to perform a reaction, hydrochloric acid aqueous solution is added after the reaction to perform acidolysis degreasing, and finally (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl) phosphonic acid is obtained through extraction, reflux adsorption and beating purification. The process method uses 3,6-dimethoxy-9H-carbazole as a starting material, realizes the synthesis of the target product through one-pot reaction, has mild reaction conditions, uses non-toxic raw materials which are easy to obtain, has simple synthesis process, is convenient to operate, and has high separation yield.

The present invention discloses a method for detecting and applying C1-C2-alkyl-substituted phenol isomers, which relates to the technical field of environmental detection and includes: selecting a corresponding sample pretreatment process to prepare a test sample according to the petroleum content range in the sample; under a mobile phase of methanol-5.0-6.5 mmol / L ammonia water, using LC-MS to detect the test sample to obtain the concentration of the first component and the standardized concentrations of co-eluted 3,5-dimethylphenol and 2,6-dimethylphenol; under a mobile phase of acetonitrile-4.0-10.0 mmol / L ammonia water, using LC-MS to detect the test sample to obtain the concentration of 3,5-dimethylphenol, or the standardized concentrations of co-eluted 3,5-methylphenol and 3-ethylphenol, or the standardized concentrations of co-eluted 2,6-dimethylphenol and 2,4-dimethylphenol; under a mobile phase of methanol-5.0-6.5 mmol / L ammonia water or acetonitrile-4.0-10.0 mmol / L ammonia water, using LC-MS to separately detect the calibration samples of the co-eluted components, and calculate the conversion factor of the co-eluted components and the concentration of the other component. The present invention realizes the accurate quantification of phenol and 12 C1-C2-alkyl-substituted phenol isomers.

The invention relates to the technical field of organic synthesis, in particular to a method for constructing Orforglipron pyran ring chirality through enzyme catalysis, which comprises the following steps: step S1, taking SM1 and SM2 as raw materials, and reacting under the action of a palladium catalyst and a ligand to obtain INT-1; step S2; carrying out hydrogenation reduction on double bonds of the INT-1 under the catalysis of Pd / C to obtain INT-2; s3, carrying out hydrolysis resolution on the INT-2 in a solvent, a buffer salt system and enzyme catalysis to obtain a chiral pure intermediate INT-3; step S4, performing ring closing on the INT-3 through a Grignard reaction to synthesize a lactone intermediate INT-4; and S5, carrying out Diball-H reduction, quenching, dichloromethane extraction and anhydrous sodium sulfate drying on the INT-4, and then reducing by using triethyl silane to obtain the compound with the general formula A. Chirality is constructed through enzyme catalysis, isomer impurities do not need to be split and separated through SFC when the chirality is constructed, loss is reduced, the yield is increased, and a target product is obtained with high yield and high chiral selectivity; meanwhile, the cost is relatively reduced, and the cost is saved.

The invention discloses a CO2 trapping absorbent which comprises 20%-50% of proton type ionic liquid, 20%-50% of a phase conversion driving agent and 20%-40% of water, and the phase inversion driving agent is one or a mixture of more of N, N-dimethyl formamide, N-methyl pyrrolidone, pentamethyldiethylenetriamine, tetramethylethylenediamine, tetramethylethylenediamine, tetramethylenediamine, tetramethylethylenediamine and dimethyl piperazine, and the phase inversion driving agent is one or a mixture of more of N, N-dimethyl formamide, N-methyl pyrrolidone, pentamethyldiethylenetriamine, tetramethylethylenediamine, tetramethylethylenediamine and dimethyl piperazine. The absorbent disclosed by the invention has the outstanding advantages of low viscosity, high absorption rate, high regeneration efficiency, high circulation capacity and low regeneration energy consumption, and has a good application prospect.

The invention relates to a flame-retardant inorganic quick-setting material and a preparation method thereof, and the flame-retardant inorganic quick-setting material is prepared from the following raw materials: sulphoaluminate cement, aluminum-magnesium hydrotalcite, phosphorus slag powder, waste PBO fiber, an accelerator, a water reducer, a functional auxiliary agent, and 3, 3 '-diamino-4, 4'-difluorodiphenyl sulfone. The functional auxiliary agent comprises structural units introduced by the following monomers: 3-[N, N-dimethyl-[2-(2-methylpropyl-2-enoyloxy) ethyl] ammonium] propane-1-sulfonic acid inner salt, diphenyl (4-vinyl phenyl) phosphine oxide, 1, 3-bis (oxirane methyl)-5-(2-allyl)-1, 3, 5-triazine-2, 4, 6 (1H, 3H, 5H)-triketone, 10-(4-vinyl phenyl)-10H-phenoxazine and itaconic acid. The material is high in strength, remarkable in rapid hardening and flame-retardant effect, and safe and environment-friendly to use.

The invention belongs to the technical field of polyurethane pouring sealants, and particularly relates to a two-component hydrophobic heat-resistant polyurethane pouring sealant and a preparation method thereof. The pouring sealant is prepared by reacting a component A and a component B, the component A is prepared from the following raw materials in parts by weight: 17 to 33 parts of modified polyether polyol I; 15 to 27 parts of modified polyether polyol II; 18 to 30 parts of diisocyanate; 20 to 34 parts of a plasticizer; the component B is prepared from the following raw materials in parts by weight: 47 to 64 parts of polyether polyol III; 36 to 53 parts of filler; and 0.15 to 0.35 part of a catalyst. Introducing a silicon-oxygen-silicon chain segment into a polyether polyol structure through acrylic acid bridging to prepare siloxane modified polyether polyol; more side ethyl, phenyl and neopentyl structures are introduced into the polyether polyol, so that the intrinsic hydrophobicity and temperature resistance of the raw materials are further improved, and the polyurethane pouring sealant shows relatively high hydrophobicity and heat resistance.

The invention discloses a process and a device for preparing insoluble sulfur by comprehensively utilizing methyl / ethyl byproduct sulfur. The device comprises a distillation kettle, the distillation kettle is communicated with a quenching box through a pipeline, a turbulent flow assembly is fixed in the quenching box, a water channel fixedly connected with the quenching box is arranged at the lower end of the turbulent flow assembly, and a cooling spraying assembly is arranged at the lower end of the water channel. A transmission rod in transmission connection with the turbulent flow assembly and the cooling spraying assembly is arranged at the lower end of the water channel, the lower end of the transmission rod is in transmission connection with a grinding assembly, the cooling spraying assembly comprises a cooling part and a spraying part, the cooling part comprises a cooling disc, the interior of the cooling disc is hollow, and multiple circles of concentrically-arranged cooling pieces are arranged at the upper end of the cooling disc; the cooling plates are provided with air channels, the upper end of the cooling disc is rotationally connected with a rotating ring, cooled carbon disulfide is introduced into the cavity of the cooling disc, the cooling plates are arranged on the cooling disc, the contact area with byproduct sulfur steam is increased, and the byproduct sulfur steam can be rapidly cooled conveniently.

The invention relates to the field of molecular photoelectric devices, and provides a single photon source based on an up-conversion photoelectric device and a preparation method thereof, and the preparation method comprises the steps: preparing a dielectric layer; preparing a graphene array electrode on the dielectric layer; constructing a graphene nano gap point electrode pair; placing the graphene nano gap point electrode pair in a two-neck flask, adding 1-(3-dimethylaminopropyl)-3-2-ethylcarbodiimide hydrochloride and an up-conversion luminescent molecule A part into the two-neck flask, adding anhydrous pyridine into the two-neck flask in a nitrogen environment, and stirring to obtain a graphene nano gap point electrode pair; and putting the device connected with an up-conversion luminescent molecule part A at two ends and an up-conversion luminescent molecule part B containing lanthanide metal into a tetrahydrofuran solution for molecular system chelation to obtain the single-molecule up-conversion photoelectric device containing the chiral group. A liquid metal Ga2O3 protective layer is plated on a single-molecule up-conversion photoelectric device, so that a single photon source is obtained, and the stability and the anti-interference capability of the single photon source are enhanced.

The disclosure relates to a particulate composition comprising ensifentrine, wherein the particulate composition further comprises: from greater than 0.00 wt % to 0.60 wt % of 1,3-bis(2-(2-(mesitylimino)-9,10-dimethoxy-4-oxo-6,7-dihydro-2H-pyrimido [6,1-a]isoquinolin-3(4H)-yl)ethyl)urea (BMIQU) relative to the total weight of ensifentrine; and from 0.00 wt % to 0.50 wt % of a biuret impurity of formula (A) relative to the total weight of ensifentrine. Further disclosed herein are liquid pharmaceutical compositions comprising the particulate composition, and a process for producing the particulate composition are also described.

The invention discloses a synthesis method of vitamin C ethyl ether, and belongs to the technical field of vitamin derivative synthesis. The synthesis method comprises the following steps: adding vitamin C, benzaldehyde and a catalyst into a first organic solvent, carrying out an aldolization reaction, adding an organic alkali after the aldolization reaction is finished, carrying out a neutralization reaction, adding an alkylation reagent, carrying out an alkylation reaction, and removing the first organic solvent after the alkylation reaction is finished, so as to obtain the vitamin C benzaldehyde. The preparation method comprises the following steps: adding a first organic solvent into a first organic solvent, pulping, filtering, collecting filter residues, washing and drying to obtain 5, 6-O-benzyl-3-O-ethyl-L-ascorbic acid, carrying out hydrogenation deprotection on the 5, 6-O-benzyl-3-O-ethyl-L-ascorbic acid, filtering after hydrogenation deprotection, collecting filtrate, crystallizing, collecting precipitate, washing and drying to obtain the 5, 6-O-benzyl-3-O-ethyl-L-ascorbic acid. The vitamin C ethyl ether is obtained. The synthesis method provided by the invention is simple to operate and high in production efficiency, and the obtained vitamin C ethyl ether is high in yield and purity.

The invention provides a salt-responsive temperature-resistant salt-resistant water-based drilling fluid tackifying filtrate reducer as well as a preparation method and application thereof, and belongs to the technical field of drilling. The tackifying filtrate reducer is prepared from the following raw materials in parts by mass: 30 to 50 parts of 1-(2-carboxyethyl)-2-vinylpyridine, 20 to 40 parts of (3-(methacrylamido) propyl) dimethyl (3-thiopropyl) ammonium hydroxide inner salt, 35 to 55 parts of N, N-dimethylacrylamide, 10 to 25 parts of 4-vinylpyridine, 300 to 500 parts of water and 1 to 5 parts of an initiator. According to the filtrate reducer, cations and anions are concentrated on one monomer molecule, so that the synthesized product contains the cations and the anions with the same charge number, has good adsorption capacity and salt response characteristics, is compatible with salt essentially, can effectively resist high temperature and high salt, and can be recycled. And the viscosity-increasing and filtrate-reducing agent has good viscosity-increasing and filtrate-reducing effects on the drilling fluid.

The invention discloses an alpha, omega-diiodo perfluoroalkane derivative, an alpha, omega-diiodo ethyl perfluoroalkane derivative as well as a preparation method and application of the alpha, omega-diiodo perfluoroalkane derivative and the alpha, omega-diiodo ethyl perfluoroalkane derivative. According to the method, alpha, omega-diiodo perfluoroalkane is taken as a raw material, and the alpha, omega-diiodo perfluoroalkane and ethylene are subjected to free radical addition reaction under the action of an initiator and a solvent to prepare the alpha, omega-diiodo ethyl perfluoroalkane. The alpha, omega-diiodoethyl perfluoroalkane and alkali are subjected to a one-molecule and / or two-molecule hydrogen iodide hydride elimination reaction, and alpha, omega-iodoethyl vinyl perfluoroalkane and / or alpha, omega-divinyl perfluoroalkane are / is generated. The method is simple and convenient to operate, the raw material utilization rate and the target product yield are high, the preparation cost is effectively reduced, and the industrial production requirement is met. The alpha, omega-diiodo perfluoroalkane derivative or alpha, omega-diiodo ethyl perfluoroalkane derivative prepared by the method disclosed by the invention can be used as a vulcanization point monomer for preparing peroxide vulcanized fluororubber, and compared with common rubber, the rubber has more excellent compression deformation performance, strength and medium resistance and has a wide application prospect.

The invention belongs to the technical field of flame retardant materials, and provides a polymer additive and a preparation method thereof, and a polymer composition, the polymer additive comprises the following components by mass: 95-99.88 parts of diethyl phosphinate, 0.1-3 parts of ethyl butyl phosphinate, 0.01-1 part of ethyl phosphonate, and 0.01-1 part of monoethyl phosphinate; the water-soluble acid value of the polymer additive is 0.1-0.3 mg KOH / g, and the polymer additive has low acidity, and when the polymer additive is used as a flame retardant for a polymer composition, the generation of high-temperature decomposition of dialkyl phosphinic acid can be slowed down, so that the polymer composition has lower water boiling precipitate content, the use stability of the polymer composition under damp and hot conditions is improved, the service life of the polymer composition is prolonged, and the service life of the polymer composition is prolonged. And moreover, the amount of mold scale generated in the injection molding process is smaller, the injection molding production efficiency can be improved, and the product appearance is improved.

The invention discloses a method for detecting glufosinate-ammonium residues in coffee in dual modes of colorimetry and chemiluminescence, and belongs to the technical field of chemical analysis and detection.The method comprises the steps that Schiff base formed by 4-aminoantipyrine and glutaraldehyde serves as a complexing agent of Cu < 2 + >, and then a copper-doped carbon dot Cu-CDs nano-enzyme is prepared through microwave digestion; according to the present invention, the Cu-CDs nano-enzyme has excellent peroxidase-like activity, can oxidize the colorless 2, 2 '-biazo-bis-3-ethylbenzothiazoline-6-sulfonic acid into the blue-green oxidized ABTS, and can improve the chemiluminescence intensity of the reaction of N-(4-aminobutyl)-N-ethylisoluminol and H2O2 by nearly 100 times when the Cu-CDs nano-enzyme is used as the chemiluminescence catalyst; based on the inhibition effect of glufosinate-ammonium on the activity of Cu-CDs POD, a sensitive and rapid colorimetric and chemiluminescence two-channel GM detection technology is developed, and the method has potential application value in the aspect of coffee safety monitoring.

The present disclosure relates to the technical field of drilling fluid, and discloses a high density environmentally friendly polymer water-based drilling fluid with resistance to 240° C. and saturated salts, a preparation method therefor and use thereof. The water-based drilling fluid comprises a micro-crosslinked heterocyclic polymer filtrate reducer, a hyper-branched strongly adsorbed filtrate reducer, a nanometer intercalated complex shearing potentiator, a flexible outer and rigid inner microsphere plugging agent, and water, wherein the micro-crosslinked heterocyclic polymer filtrate reducer is prepared by reacting sodium p-styrene sulfonate, N,N,N-trimethyl-3-(2-methylallylamino)-1-propyl ammonium chloride, N,N-diethyl acrylamide, N-vinyl caprolactam, tetramethyl ethylenediamine with phenyl triethoxy silane. The high density environmentally friendly polymer water-based drilling fluid with resistance to 240° C. and saturated salts of the present disclosure can exhibit good performance at high temperature and high salinity conditions, and has desirable weighting capability, it can meet the requirements of drilling well in the deep oil and gas formations.

The invention relates to the technical field of coatings, and provides an antifouling coating as well as a preparation method and application thereof. The antifouling paint comprises a component A and a component B, wherein the component A comprises fluorosilicone modified acrylic resin, fluorinated paraffin, modified nano attapulgite, a wetting agent, a defoaming agent and a dispersing agent; a modifying agent of the modified nano attapulgite is 2-imidazole-1-ethylamine and 2-(3, 4-cyclohexyl oxide) ethyl triethoxy silane, and a modifying agent of the modified nano attapulgite is 2-imidazole-1-ethylamine and 2-(3, 4-cyclohexyl oxide) ethyl triethoxy silane; and the component B comprises a curing agent and a diluent. The nano attapulgite is modified, so that the dispersity of the nano attapulgite in the coating and the compatibility of the nano attapulgite with resin are improved, the nano attapulgite can be subjected to cross-linking reaction with other network structures to form a more compact cross-linked network, and the mechanical strength and the wear resistance of the coating are further improved.

The invention discloses an organic amine composite absorbent for carbon capture and application thereof, and belongs to the technical field of carbon dioxide capture, the organic amine composite absorbent for carbon capture is in a solution state and comprises the following components: a main agent, an auxiliary agent, an accelerant A, an accelerant B and water; wherein the mass ratio of the main agent to the auxiliary agent is 2: (1-2); the mass ratio of the auxiliary agent to the accelerant A is 2: (1-2); the mass ratio of the accelerant A to the accelerant B is 2: (1-2); the total mass concentration of the main agent, the auxiliary agent, the accelerant A and the accelerant B in the organic amine composite absorbent for carbon capture is 30-40 wt%; the main agent is selected from N-methyldiethanolamine or N, N-diethyl ethanolamine, the auxiliary agent is selected from piperazine or hydroxyethyl ethylenediamine, the accelerant A is selected from triethylene glycol monomethyl ether and / or ethylene glycol monomethyl ether, and the accelerant B is selected from ethyl butyl ether and / or isobutyl ether. The organic amine composite absorbent for carbon capture has a wide application prospect in removal of carbon dioxide in flue gas.

The invention belongs to the technical field of coking product extraction and organic separation, and particularly relates to a method for refining 2, 3, 5-tricresol and 3-methyl-5-ethyl phenol from a tricresol mixture. According to the method for refining the 2, 3, 5-tricresol and the 3-methyl-5-ethyl phenol from the tricresol mixture, the tricresol mixture is rectified to obtain the mixed tricresol, the mixed tricresol and the isobutene are subjected to the tert-butylation reaction under the action of the catalyst, and due to the fact that the 2, 3, 5-tricresol and the 3-methyl-5-ethyl phenol do not react with the isobutene, the 2, 3, 5-tricresol and the 3-methyl-5-ethyl phenol are not reacted with the isobutene. The method comprises the following steps: taking 2, 3, 5-trimethylphenol as a raw material, reacting other phenols with isobutene to generate corresponding tert-butyl phenol, boiling point of a tert-butyl product is obviously higher than that of 2, 3, 5-trimethylphenol and 3-methyl-5-ethyl phenol, performing rectification to obtain a 3-ethyl-5-cresol crude product and a 2, 3, 5-trimethylphenol crude product, and performing solvent refining and melt crystallization to obtain 3-ethyl-5-cresol of which the content is greater than or equal to 99% and 2, 3, 5-trimethylphenol of which the content is greater than or equal to 99%.

The invention discloses a temperature / CO2 dual-response zwitterionic hydrogel profile control agent, which is prepared by taking a monomer A, a monomer B and a monomer C as raw materials, adding a cross-linking agent and an initiator, and carrying out polymerization reaction in a water medium. The monomer A is selected from any one of acrylamide, acrylic acid and 1-vinyl-2-pyrrolidone; the monomer B is selected from any one of [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide, 2-methacryloyloxyethyl phosphorylcholine and 3-((2-(methacryloyloxy) ethyl) dimethylamino) propionic acid inner salt; and the monomer C is selected from any one of 2-(dimethylamino) ethyl methacrylate, dimethylamino propyl methacrylamide and polyethyleneimine. The profile control agent has double swelling mechanisms, has outstanding temperature and salt resistance, resists 220000 mg / L of mineralization water, is suitable for high-salt reservoirs, and is good in long-term aging property.

The invention relates to the technical field of carbon nanotube materials, in particular to high-dispersity carbon nanotube slurry and a preparation method thereof. Ammonium chloride, sodium azide, novolac epoxy resin and carbon nanotubes are added for modification treatment, and the modified carbon nanotubes are obtained. Then, a silane coupling agent KH550, an MXene material, a palmitic acid solution, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide are added and mixed, and the modified MXene material is obtained. And performing ultrasonic dispersion on polyvinylpyrrolidone, N-methyl pyrrolidone, the modified carbon nanotubes and the modified MXene material to obtain the composite conductive filler. The finished product is obtained by adding the surfactant, the deionized water and the composite conductive filler. The finished product prepared by the method has good conductivity and dispersity, so that the finished product has a wide application prospect in the technical field of carbon nanotube materials.

The invention belongs to the technical field of thin film capacitors, and particularly relates to a chemical grafting modified polypropylene capacitor film material and a preparation method and application thereof. According to the preparation method of the chemical grafting modified polypropylene capacitor film material, provided by the invention, diethylenetriamine ethyl acrylate with a plurality of specific groups such as amino groups and carboxyl groups and unsaturated double bonds is synthesized through esterification reaction, and the diethylenetriamine ethyl acrylate is introduced into a polypropylene material through chemical grafting to obtain chemical grafting modified polypropylene; the prepared polypropylene capacitor film material has the excellent properties of good compatibility, difficulty in film breakage, capability of adsorbing and removing residual moisture, difficulty in oxidation corrosion, excellent breakdown resistance and the like, and the preparation method is a preparation method of the high-performance polypropylene capacitor film material; therefore, the technical problem that a polypropylene capacitor film material prepared in the prior art is low in performance is solved.

Described herein are polymorphs comprising 2′,6-difluoro-5′-(1-hydroxy-1-methylethyl)-imidazo[1,2-b][1,2,4] triazin-7-ylThiphenyl-2-carbonitrile (TPA023B) or salts thereof. In one aspect, disclosed herein is a crystalline polymorphic salt or co-crystal of TPA023B with phosphoric acid. Also described herein are methods of making and using the same.

The invention relates to a whitening composition containing pH-sensitive oxidized resveratrol hydrogel and application. The whitening composition is a composition of oxidized resveratrol hydrogel, a hydrolyzed opuntia pear flower extract and a mexican agastache rugosus flower / leaf / stem extract in a weight ratio of 1: (0.6-0.7): (0.01-0.02). The oxidized resveratrol hydrogel is prepared from the following raw materials in percentage by weight: 1 to 3 percent of oxidized resveratrol, 1 to 3 percent of 3-o-ethyl ascorbic acid, 15 to 20 percent of butanediol, 0.1 to 0.5 percent of sodium alginate, 0.1 to 0.5 percent of carboxymethylcellulose, 0.3 to 0.8 percent of calcium chloride and the balance of water. The three components of the whitening skincare product have a remarkable synergistic effect in the whitening aspect, the skin color can be jointly improved from different mechanisms, and meanwhile, the mildness and the safety are considered.

Provided are a whitening and freckle-removing composition, a gel, a preparation method therefor, and a use thereof, relating to the technical field of skin-care products. The whitening and freckle-removing composition comprises tranexamic acid, nicotinamide, 4-butylresorcinol, licorice extract, 3-o-ethyl ascorbic acid, and glutathione. For the whitening composition, by inhibiting the activity of tyrosinase, blocking the transfer of melanin from melanocytes to keratinocytes, and inhibiting the formation and accumulation of melanin by means of multiple mechanisms including oxidation resistance, and by means of the synergistic action of all components, cosmetic benefits of whitening and freckle-removing are achieved. The whitening and freckle-removing gel has a simple preparation method, has a mild and non-sensitizing formula, is safe and non-irritating, and is suitable for large-scale production and application.

The invention relates to the technical field of drilling compositions, in particular to a self-suspending proppant for low-water fracturing. The invention provides a self-suspending proppant for less-water fracturing. The self-suspending proppant comprises a modified proppant and a quadripolymer adsorbed on the surface of the modified proppant, the modified proppant is obtained by carrying out surface modification on a proppant through a modifier, and the modifier is a silane coupling agent and / or a nonionic surfactant; comonomers of the quadripolymer are acrylamide, 2-acrylamide-2-methylpropanesulfonic acid, 2-methacryloyloxyethyl trimethyl ammonium chloride and acrylic acid respectively. The four comonomers are adopted to form a quadripolymer, so that the salt resistance of the self-suspending proppant can be greatly improved, and the self-suspending proppant can still keep better suspending performance in a solution with higher mineralization degree and has better low-temperature gel breaking performance.

The disclosure relates to a particulate composition comprising ensifentrine, wherein the particulate composition further comprises: from greater than 0.00 wt % to 0.60 wt % of 1,3-bis(2-(2-(mesitylimino)-9,10-dimethoxy-4-oxo-6,7-dihydro-2H-pyrimido[6,1-a]isoquinolin-3(4H)-yl)ethyl)urea (BMIQU) relative to the total weight of ensifentrine; and from 0.00 wt % to 0.50 wt % of a biuret impurity of formula (A) relative to the total weight of ensifentrine. Further disclosed herein are liquid pharmaceutical compositions comprising the particulate composition, and a process for producing the particulate composition are also described.