895 results about "Straight chain" patented technology

An organometallic complex is represented by general formula (1).M is Pd or Pt. B-A-B is a tetradentate ligand formed by bonding a ring A to rings B. The ring A is a hydrocarbon aromatic ring or heteroaromatic ring that may have a substituent, and is selected from a benzene ring, etc. The substituent that the ring A may have is selected from a linear or branched C1 to C6 alkyl group, etc. Each of the rings B is a monocyclic heteroaromatic ring that may have a substituent, and is selected from a pyridine ring, etc. The substituent that the ring B may have is selected from a linear or branched C1 to C6 alkyl group, etc. Each X-Y is a bidentate ligand, and atoms bonded to M are selected from C, N, and O atoms. The two bidentate ligands do not bond together.

The invention relates to the technical field of lubricating oil, and discloses a low-temperature-resistant lubricating oil composition and a preparation method thereof. Mineral oil, modified polymethacrylate, a dispersing agent, an antioxidant and an oil defoaming agent are stirred and mixed and then filtered, and the low-temperature-resistant lubricating oil composition is obtained. The cross-linking agent enables polymethacrylate to form a light cross-linked structure, and stress can be dispersed during shearing; nitrogen atoms in triazinyl, pyridyl, pyrrolidone and Mannich base structures serve as hydrogen bond receptors, the hydrogen bond interaction with hydroxyl on a polymethacrylate molecular chain is enhanced, a physical cross-linked network is formed, and the shear resistance is further improved; in the modified low-temperature-resistant monomer, the glass-transition temperature can be remarkably reduced by high flexibility of silicon oxygen bonds in long straight-chain alkyl and silane groups, so that a molecular chain can still move at a low temperature, and the low-temperature fluidity of the lubricating oil is improved; the cyclic structure of cyclohexyl can effectively interfere with the ordered arrangement of wax crystals, reduce the pour point of the lubricating oil and improve the low-temperature fluidity.

The invention provides a fluorosilane modified gemini surfactant and a preparation method thereof, a resistance reducing agent and a preparation method thereof, and a polymer fracturing fluid. The fluorosilane modified gemini surfactant has a structure as shown in a formula I, wherein R1 is selected from one or a combination of more than two of saturated alkyl, alkylaryl, alkylalkyloxy, alkylacyl and unsaturated alkyl with 1-8 carbons, and R2 is selected from one or a combination of more than two of alkyl, alkylaryl, alkylalkyloxy, alkylacyl and unsaturated alkyl with 1-8 carbons; (CF2) the number of n in n is 1 to 18; x <-> is Br <-> and / or I <->; and R2 is selected from one or a combination of more than two of straight-chain saturated alkyl, branched-chain saturated alkyl, alkylaryl, alkylalkoxy, alkyl ester group and unsaturated alkyl with 1-8 carbons. According to the invention, the fluorosilane modified gemini surfactant is used as a hydrophobic monomer of the resistance reducing agent, so that the synthesized resistance reducing agent has a single-head and double-tail gemini surfactant structure, the tackifying and sand-carrying capabilities are improved, and the surface and interface tension of a gel breaking solution and reservoir rocks is reduced.

The present invention provides an electronic or electrical device or component thereof comprising a cross-linked polymeric coating on a surface of the electronic or electrical device or component thereof; wherein the cross-linked polymeric coating is obtainable by exposing the electronic or electrical device or component thereof to a plasma comprising a monomer compound and a crosslinking reagent for a period of time sufficient to allow formation of the cross-linked polymeric coating on a surface thereof,wherein the monomer compound has the following formula:where R1, R2 and R4 are each independently selected from hydrogen, optionally substituted branched or straight chain C1-C6 alkyl or halo alkyl or aryl optionally substituted by halo, and R3 is selected from:where each X is independently selected from hydrogen, a halogen, optionally substituted branched or straight chain C1-C6 alkyl, halo alkyl or aryl optionally substituted by halo; and n1 is an integer from 1 to 27; and wherein the crosslinking reagent comprises two or more unsaturated bonds attached by means of one or more linker moieties and has a boiling point at standard pressure of less than 500° C.

This invention relates to a polyurethane microcapsule emulsion, its preparation method, and its application. The raw materials for preparing the polyurethane microcapsule emulsion, by weight, include: 30-50 parts of unsaturated polyester polyol, 10-25 parts of isocyanate monomer, 3-6 parts of hydrophilic monomer, 2-5 parts of small molecule alcohol chain extender, 1.5-5 parts of neutralizing agent, 0.1-0.5 parts of organometallic catalyst, 20-50 parts of organic solvent, 5-15 parts of pesticide active ingredient, 3-10 parts of C6-C15 straight-chain or branched-chain olefin monomer, 0.1-0.5 parts of initiator, and 100-160 parts of water. The polyurethane microcapsule emulsion provided by this invention solves the problems of low crosslinking density, simple structural topology, insufficient hydrophobicity, and poor encapsulation stability of existing pesticide microcapsules, improving the controlled-release performance, capsule wall density, and emulsion system stability of the polyurethane microcapsule emulsion.

This nonspecific reaction inhibitor is a copolymer containing a first repeating unit represented by formula (1) and a second repeating unit represented by formula (2). In formula (1), R1, R2, and R3 are each independently a hydrogen atom or a methyl group, X is NH or an oxygen atom, Y is SO3 - or COO-, and Yn and m are each independently an integer from 1 to 5. In formula (2), R4 is a hydrogen atom or a methyl group, Z is NH or an oxygen atom, and A is a linear or branched alkyl group with 12 to 40 carbon atoms.

The invention belongs to the field of petrochemical engineering, and discloses a bimetallic Ni-Pt / RFE hydroisomerization catalyst and a preparation method and application thereof. The preparation method comprises the following steps: dissolving a nickel precursor in water, stirring until clarification, and dropwise adding ammonia water to obtain a mixed solution 1; rFE is added into the mixed solution 1, the pH value is adjusted to be 9-11.5, suction filtration, washing and drying are conducted after stirring, and Ni / RFE is obtained; dissolving a platinum precursor in water, stirring until the solution is clear, and dropwise adding ammonia water to obtain a mixed solution 2; and adding the Ni / RFE into the mixed solution 2, adjusting the pH value to 9-11.5, stirring, and carrying out suction filtration, washing, drying and roasting to obtain the Ni-Pt / RFE. The method is simple and convenient to operate and mild in condition, the catalyst activity and the isomerization efficiency are remarkably improved through the synergistic effect of Ni and Pt, the catalyst preparation cost is greatly reduced while the use amount of precious metal is reduced, efficient conversion of long straight-chain alkane can be achieved, and the isomerization conversion rate of n-dodecane within 60 minutes can reach nearly 90%.

The invention provides an aqueous zinc ion battery electrolyte, a preparation method thereof and a zinc ion battery, and belongs to the technical field of aqueous zinc ion batteries. The aqueous zinc ion battery electrolyte comprises an additive, an inorganic zinc salt and a solvent, the additive comprises at least one of trimethylamine substituted by 1-3 substituent groups, benzene and C3-C10 straight-chain alkane, and the substituent groups comprise phosphonic acid groups or phosphinic acid groups; the solvent comprises a sodium chloride aqueous solution. By adopting the additive with a specific structure and the solvent containing the sodium chloride aqueous solution, the cycle performance of the zinc negative electrode in the water-based zinc ion battery can be remarkably improved, and the service life of the water-based zinc ion battery is prolonged.

The invention discloses high-elongation self-repairing polyurethane and a preparation method thereof, and the preparation method comprises the following steps: step 1, in an inert gas atmosphere, carrying out catalytic reaction on polyol and isocyanate in a solvent to prepare a polyurethane prepolymer; step 2, adding an imine chain extender and a trihydroxy cross-linking agent into the reaction solution, and carrying out chain extension reaction to obtain self-repairing polyurethane; according to the invention, a chain extender containing dynamic reversible imine bonds is adopted to carry out chain extension on a polyurethane prepolymer, and meanwhile, a trihydroxy cross-linking agent is adopted to construct a three-dimensional network structure, so that cross-linked polyurethane containing imine dynamic bonds is prepared. The imine bond can be quickly exchanged at room temperature, and after the imine bond is broken, the imine bond is different from a traditional straight-chain molecule but a branched molecule, so that the flow processing is better, the molecular chain collision probability is higher, the tensile elongation is better, and the self-repairing property is excellent at room temperature; and the prepared cross-linked polyurethane can have excellent self-repairing performance at room temperature.

The invention discloses a preparation method of a monocyclopentadienyl trialkoxy titanium precursor, and belongs to the technical field of synthesis of metal organic compounds. The method comprises the following steps: S1, reacting a deprotonation product of RnCp, (R0) mSiXz and an accelerant to obtain an intermediate I; s2, reacting the intermediate I with TiX4 to obtain an intermediate II; s3, the intermediate II and R1OM are subjected to a reaction, and a monocyclopentadienyl trialkoxy titanium precursor is prepared; r and R1 are independently selected from C1-C5 straight-chain or branched-chain alkyl groups, Cp is cyclopentadienyl, R0 is C1-C3 alkyl groups, X is halogen and is selected from any one of F, Cl, Br and I, n is an integer of 0-5, m + z is equal to 4 and 1 < = z < = 2, and M is alkali metal. The synthesis route has good safety and economical efficiency, the yield of the industrial synthesis route is remarkably improved, the reaction time is short, the synthesis efficiency is high, and the industrial application value is high.

The invention relates to the technical field of aluminum electrolytic capacitor electrolyte processing, in particular to a high-performance aluminum electrolytic capacitor electrolyte and a preparation method thereof. The invention discloses a water-soluble conductive agent, which is prepared from the following raw materials in percentage by weight: 5 to 10 percent of conductive salt, 0.1 to 2 percent of corrosion inhibitor, 3 to 5 percent of butyl-terminated fatty alcohol-polyoxyethylene ether, 2 to 5 percent of polyacrylic acid-polyacrylamide diblock copolymer, 0.5 to 2 percent of additive, 0.5 to 2 percent of straight-chain polycarboxylic acid, 6 to 10 percent of ionic liquid and the balance of solvent, the butyl-terminated fatty alcohol-polyoxyethylene ether has the structural formula of R-O-(CH2CH2O) xCH2CH2OBu, r represents a fatty alcohol group, is C12-18 alkyl, and is a straight chain or a branched chain; n is the addition number of ethylene oxide, and x is equal to 10-50; through the synergistic effect of the components in the formula, a stable and efficient electrolyte system is formed, the performance and reliability of the aluminum electrolytic capacitor in severe environments such as high temperature and low temperature are remarkably improved, the service life of the aluminum electrolytic capacitor is prolonged, and the requirements of modern electronic equipment for high-performance capacitors are met.

The invention provides a vanadium-based metal organic framework material as well as a preparation method and application thereof, and belongs to the technical field of metal organic framework materials. The vanadium-based metal organic framework material is of a three-dimensional framework structure formed by connecting a one-dimensional vanadium oxygen chain and a squaric acid ligand through coordinate bonds. The preparation method of the vanadium-based metal organic framework material comprises the following steps: adding a vanadium source and an organic ligand into an acidic aqueous solution for solvothermal reaction to obtain the vanadium-based metal organic framework material, and the organic ligand is squaric acid. The vanadium-based metal organic framework material provided by the invention can be used for separating straight-chain alkane and isomers thereof.

The invention relates to the technical field of light-cured materials, in particular to light-cured resin as well as a preparation method and application thereof. The structural general formula of the light-cured resin is as shown in formula 1, wherein R1 is selected from one of C1-C20 straight-chain alkyl, branched-chain alkyl and cyclic alkyl; r2 is selected from hydrogen or methyl; r3 is selected from one of ethylene, propylene and butylidene; r4 is selected from one of hydrogen, methyl and cyclohexyl; n1 is an integer selected from 1-40, and n2 is an integer selected from 10-60. The resin is a multi-block polymer containing phosphorus oxide, organic silicon chain segments and unsaturated double bonds, has light curing activity and low stripping performance, and meanwhile has good adhesive force and does not generate migration; and when being applied to the optical UV imprinting adhesive, the high-precision transfer printing of the optical film with special textures and fine patterns can be obviously improved, the mold residue is reduced, the service life is prolonged, and the high quality, high yield and long-term stability of the optical film are ensured.

The invention discloses a single-chain alkylamino glycerol compound, a preparation method and application. The structural general formula of the single-chain alkylamino glycerol compound is R-NH-CH2-CHOH-CH2OH, the single-chain alkylamino glycerol compound is used for preventing and controlling peach monilinia and / or botryosphaeria dothidea, and R is a C8-C18 straight chain or branched chain and saturated or unsaturated alkyl. The single-chain alkylamino glycerol compound provided by the invention can be prepared by reacting glycidol and alkylamine under mild conditions, has a remarkable inhibition effect on peach monilinia and botryosphaeria dothidea, and can induce fungal membrane rupture, anti-oxidation system imbalance and lipid peroxidation, so that fungus killing is realized. The device can be widely used for fruit and vegetable postharvest preservation, orchard spraying and green pesticide development.

[Problem] To provide a stabilizer for suppressing generation of silane from a polysilane composition and a method for suppressing generation of silane. To provide a method for inactivating a polysilane, and a polysilane inactivated treatment composition.[Means for Solution] A stabilizer represented by the following formula for suppressing generation of silane from a polysilane composition: CH2═CH—R1 wherein R1 is C3-20 linear, branched or cyclic alkyl group, C2-15 linear or branched alkenyl group or C7-20 aryl group substituted with alkenyl group.[Selected Drawing] None

The present application relates to the field of high polymer material, and particularly relates to a preparation method of ultra-high molecular weight polyethylene film, which has the following steps: after ultra-high molecular weight polyethylene resin and solvent are configured into a uniform suspension, the suspension is sent into a double screw extruder to obtain a high temperature melt, the melt is passed through a metering pump and a slit die, and is cooled and shaped by a polished cold roller to obtain a gel film, then the solvent in the film is removed by extraction, the film after extraction is dried by hot air, and finally the film is synchronously or stepwise bidirectionally hot stretched to obtain the ultra-high molecular weight polyethylene film. The present application adopts a new wet process route of dissolving folded chain lamellae and retaining straight chain lamellae in the preparation process of the ultra-high molecular weight polyethylene solution, and makes the straight chain crystals be kept in the preparation process of the ultra-high molecular weight polyethylene film, so that the resin content in the solution in the preparation of the ultra-high molecular weight polyethylene film is greatly improved, and the production efficiency is greatly improved.

The invention provides a phosphorus-nitrogen coordinated metallocene compound and a preparation method and application thereof, the compound has a structure as shown in a formula I: in the formula I, M is selected from IVB group metals in the periodic table of elements; r1 is selected from hydrogen, halogen, C1-C10 direct or branched alkyl, and C1-C3 alkoxy; r2 is selected from hydrogen and C1-C6 straight chain or branched chain alkyl; y is selected from chlorine, C1-C3 alkyl substituted or unsubstituted by trimethylsilyl, and amino substituted by trimethylsilyl. The phosphorus-nitrogen coordinated metallocene compound provided by the invention has relatively high thermal stability, catalytic activity and comonomer insertion rate, and can realize high-temperature solution polymerization of ethylene and norbornene.

This application relates to electrolytes and electrochemical devices. The electrolyte comprises an active material and a solvent; the active material comprises a polytert-amine-substituted biphenylquinone compound with an oxidation state as shown in Formula I; in Formula I, each R1 is independently a C2-C10 branched or straight-chain alkyl group, and each R2 is independently a C1-C5 straight-chain alkylene group. The active material in the above electrolyte, including a polytert-amine-substituted biphenylquinone compound with a specific structure, possesses high potential, structural stability, and two-electron transfer characteristics, making it less prone to cross-membrane crosstalk leading to battery capacity decay. When the electrolyte containing this active material is used in electrochemical devices such as flow batteries, long-term stable operation can be achieved. Furthermore, the preparation process of this type of biphenylquinone compound is green, simple, low-cost, and easily industrialized, facilitating widespread use. Formula I

The invention relates to the technical field of photosensitive coatings, and particularly discloses high-flexibility photosensitive solder resist ink and a preparation method thereof. The high-flexibility photosensitive solder resist ink provided by the invention comprises a main agent and a curing agent, the main agent comprises a growth straight chain carboxyl-containing resin solution; the growth straight-chain carboxyl-containing resin solution is prepared by carrying out ring-opening reaction on epoxy resin, introducing beta-(acryloyloxy) acid and then carrying out esterification reaction with acid anhydride; the curing agent comprises thermosetting resin and a toughening agent; the thermosetting resin comprises biphenyl epoxy resin, and the flexibilizer is aliphatic epoxy resin. The composite effect of the straight-chain carboxyl-containing resin solution, the specific thermosetting resin and the flexibilizer is improved, the flexibility of a liquid photosensitive solder resist ink curing film can be obviously improved, and meanwhile, the liquid photosensitive solder resist ink has good chemical gold resistance and soldering resistance and is particularly suitable for a flexible circuit board.

This invention relates to a 1,3,4-thiadiazole peptide deformylase inhibitor and its preparation and application. The structural formula is shown in formula (1): wherein, R 1 It is n-butyl or cyclopentylmethyl; R 2 The compounds are hydrogen-containing, straight-chain alkanes, cyclic alkanes, aromatic rings, substituted biphenyls, or heterocyclic rings. The 1,3,4-thiadiazole peptide deformylase inhibitors provided by this invention can effectively inhibit bacterial protein synthesis, thereby achieving sterilization. These compounds exhibit excellent inhibitory activity against Gram-positive drug-resistant bacteria, especially the clinically challenging methicillin-resistant Staphylococcus aureus (MRSA). In particular, some preferred compounds show inhibitory activity 4-8 times that of the control standards vancomycin and linezolid. The 1,3,4-thiadiazole peptide deformylase inhibitors provided by this invention also exhibit inhibitory activity against Gram-negative drug-resistant bacteria, especially against drug-resistant Acinetobacter baumannii, known as "superbugs," with an inhibitory activity reaching 0.5 μg / mL, far superior to vancomycin and linezolid.

The invention provides a hepta-fused ring small molecule compound with a side chain containing deuterium atoms and a preparation method. In the structural formula # imgabs0, R1 and R2 are respectively independent deuterium atom-containing straight chain alkyl, branched chain alkyl, alkoxy, alkyl substituted phenyl, alkoxy substituted phenyl, alkyl substituted thienyl or alkoxy substituted thienyl with the carbon atom number of 1-20; a1 and A2 are respectively independent power-drawing sub-units. The compound can be used for an efficient organic photovoltaic cell, the non-radiative energy loss of a material can be effectively regulated and controlled by utilizing a heavy atom substitution effect, and the photoelectric conversion efficiency of a device is improved.

Provided is a bonding material which is capable of forming a silver bonding layer that has good bondability with a material to be bonded, wherein the density (denseness) of the silver is good. The bonding material comprises an organic acid silver salt, an organic solvent, and silver particles. The organic acid silver salt has a weight loss rate (Mr1) of 5% or less when the temperature thereof is raised from 25°C to 200°C and a weight loss rate (Mr2) of 40% or more when the temperature thereof is raised from 200°C to 280°C as determined by simultaneous thermogravimetry-differential thermal analysis (TG-DTA) (in a nitrogen atmosphere at a nitrogen flow rate of 200 ml / min and a heating rate of 10° C / min). The organic solvent contains a compound represented by general formula (1) (in the formula, R1 represents a linear or branched alkyl group having 2 to 6 carbon atoms).　The silver particles include: first silver particles that have an average particle diameter (D50 diameter) of 0.15 μm or more and 0.4 μm or less; and at least one of second silver particles that have an average particle diameter (D50 diameter) of 0.6 μm or more and 1.0 μm or less and third silver particles that have an average particle diameter (D50 diameter) of 1.9 μm or more and 2.4 μm or less.

The invention relates to the technical field of photoelectrocatalysis, in particular to a Mn (II) coordination polymer photoelectrode crystalline material and a preparation method and application thereof. The Mn (II) coordination polymer {[Mn2 (H2O) 6 (DODDA)]. 4H2O} n is obtained from an H4 (DODDA) organic ligand and manganese salt through a solvothermal method, an asymmetric unit comprises two Mn (II) ions in different coordination modes, adjacent Mn2 ions are bridged through carboxyl oxygen of the ligand to form straight chains, and two adjacent Mn2 straight chains are further bridged with Mn1 through the H4 (DODDA) ligand to form a transverse trapezoidal one-dimensional chain. A three-dimensional supramolecular structure is formed among the one-dimensional chains through the interaction of a large number of intermolecular hydrogen bonds. The Mn (II) coordination polymer shows better photoelectric property, has the potential of serving as a photoelectrode material, has good optical and electrical characteristics, can be used for constructing an efficient photoelectrocatalysis water decomposition system, and has application prospects in the aspects of photocatalytic hydrogen production, solar energy conversion and the like.

The present application provides a reversible thermochromic microcapsule pigment which is easily changed to a colored state from a colorless state by heating at a temperature in a living environment temperature range or a temperature close to a daily life temperature, and is sensitively recovered to the colorless state again. The reversible thermochromic microcapsule pigment of the present application is formed by enclosing a reversible thermochromic composition in a microcapsule, the reversible thermochromic composition comprising (A) an electron-donating colored organic compound, (B) a 4-hydroxybenzoic acid ester compound represented by the following general formula (1) as an electron-accepting compound (in the formula, R represents a linear or branched alkyl group having 12 to 22 carbon atoms), (C) a chain hydrocarbon compound or the like as a reaction medium in which reversible electron transfer reactions based on the above (A) and (B) occur, (D) a linear dibasic acid compound having 3 to 22 carbon atoms, and (E) an aromatic hydrocarbon compound or the like having a melting point of 50°C or higher.

A composition for producing polyurethane foam contains a polyisocyanate component and a polyol component, wherein the composition additionally contains at least one organic compound V which contains at least one radical RA selected from the group consisting ofwherein * denotes the bond to the remaining portion of the at least one organic compound V, and wherein R1 are independently of one another identical or different and selected from H or branched or linear alkyl radicals having 1 to 30 carbon atoms which optionally also contain heteroatoms.

The invention discloses an emulsion polymer which contains a structural unit A, a structural unit B, a structural unit C and a structural unit D. The structural unit A has a structural unit shown in a formula (1), the structural unit B has a structural unit shown in a formula (2), the structural unit C has a structural unit shown in a formula (3), and the structural unit D has a structural unit shown in a formula (4). The weight percentage of the structural unit A is 5-15%, the weight percentage of the structural unit B is 2-40%, the weight percentage of the structural unit C is 10-70%, the weight percentage of the structural unit D is 1-80%, and the viscosity average molecular weight of the emulsion polymer is 30 million to 30 million; wherein R is an alkyl group, preferably a straight chain alkyl group or a branched chain alkyl group of C6-C18.

This invention discloses a ruthenium catalyst supported on a phosphine-containing porous organic polymer and its preparation method. The phosphine-containing porous organic polymer serves as both a support and a solid ligand. The phosphine-containing porous organic polymer ligand is a random copolymer, and its structure can be represented by general formula I. The ruthenium catalyst supported on the phosphine-containing porous organic polymer according to this invention has a large specific surface area and contains a hierarchical porous structure, enabling efficient direct preparation of alcohols from olefins via reductive hydroformylation, and is easily recyclable. It exhibits excellent activity and regioselectivity in the direct preparation of alcohols from olefins via reductive hydroformylation, with an alcohol selectivity of nearly 90% and a high ratio of straight-chain alcohols to branched-chain alcohols.

The invention relates to the field of insulating materials, and discloses an insulating material and application thereof. The material is characterized by being prepared from the following raw materials in parts by weight: 100 parts of a copolymer of ethylene and at least one C3-C6 straight-chain alpha-olefin, 0.1-2.5 parts of an initiator, 0.1-2 parts of a cross-linking agent, 0-0.5 part of an antioxidant and 0-0.1 part of an acid remover. The insulating material has the beneficial effects of good crosslinking performance, thermal stability and mechanical performance.

The invention discloses a method for removing diatom through combination of pre-oxidation of sodium hypochlorite and potassium permanganate and coagulative precipitation enhancement, and belongs to the technical field of water treatment. The method comprises the following steps: adding sodium hypochlorite and potassium permanganate into diatom-containing water step by step, and carrying out a combined pre-oxidation reaction for 30-60 minutes; and then adding a coagulant to react, and standing and precipitating for about 60 minutes, so that the diatom cells in the water can be efficiently removed. Aiming at the problems of low diatom oxidation removal rate, poor coagulation effect, filter tank blockage and the like in a conventional water treatment process, straight-chain diatom cell membrane structures are primarily destroyed through sodium hypochlorite, negative electricity groups on cell surfaces are exposed, and a favorable reaction interface is provided for potassium permanganate; in-situ manganese dioxide generated by further adding potassium permanganate can coat cells and neutralize surface charges, and an ideal condition is created for the coagulant to form an adsorption bridge, so that a coagulation interface is remarkably improved, and the removal efficiency of diatom cells is improved.

What is described is a compound of formula Iconsisting of a compound in which R1 is a branched chain alkyl consisting of 10 to 31 carbons; R2 is a linear alkyl, alkenyl, or alkynyl consisting of 2 to 20 carbons; L1 and L2 are the same or different, each a linear alkylene or alkenylene consisting of 2 to 20 carbons; X1 is S or O; R3 is a linear or branched alkylene consisting of 1 to 6 carbons; and R4 and R5 are the same or different, each a hydrogen or a linear or branched alkyl consisting of 1 to 6 carbons; or a pharmaceutically acceptable salt thereof.