177 results about "Allyl alcohol" patented technology

The invention relates to the field of chemical synthesis, in particular to a production process of allyl diethylene glycol dicarbonate, which comprises the following steps: by taking allyl alcohol and dimethyl carbonate as raw materials, carrying out transesterification under the action of a core-shell catalyst to generate dipropylene carbonate; carrying out solid-liquid separation, carrying out reduced pressure distillation to recover methanol and dimethyl carbonate, and then carrying out second-step ester exchange reaction with diethylene glycol under the action of the same catalyst to generate allyl diethylene glycol dicarbonate; and finally, performing multi-stage reduced pressure distillation purification to obtain a high-purity product. According to the core-shell type catalyst, an MCM-41 molecular sieve is used as a carrier, an inner core is formed after amino modification and zirconium ion coordination, then an interface layer and a phenyl modified silicon dioxide shell are used for packaging, and the core-shell type catalyst has high activity, high selectivity and excellent structural stability. The method has the advantages of mild process conditions, recyclable catalyst, high product yield and excellent purity, and is suitable for industrial production.

The invention provides modified polysiloxane and also provides a preparation method of the modified polysiloxane, and the preparation method comprises the following steps: mixing low-hydrogen-content silicone oil with allyl alcohol polyether and allyl glycidyl ether, heating, adding a catalyst, and carrying out an addition reaction to obtain the modified polysiloxane. The invention also provides an application of the modified polysiloxane as a soil loosening agent, and the modified polysiloxane is used for reducing the soil bulk density and / or increasing the soil porosity, and is also used for improving the water absorption and / or water retention of the soil. By applying the modified polysiloxane soil loosening agent disclosed by the invention, the soil bulk density is effectively reduced, the soil compactness is reduced, and the soil porosity is improved, so that the soil hardening is remarkably improved, the crop growth is promoted, and the modified polysiloxane soil loosening agent is green and safe and has important economic value and environmental significance.

The invention belongs to the field of preparation of allyl polyether, and particularly relates to a preparation method of epoxy allyl alcohol polyether. The invention aims to solve the problems of complex traditional multi-step synthesis process and long reaction period. The preparation method comprises the following steps: mixing allyl alcohol polyether with alkali, adding an epoxy end-capping reagent under the protection of nitrogen, carrying out a curing reaction, carrying out solid-liquid separation after the reaction to obtain a crude product, removing impurities by using an adsorbent, and carrying out demonomerization treatment and filtration to obtain a final product. According to the method, the production process is simplified, the cost is reduced, the purity and the performance of the product are improved, the product has relatively low viscosity, good flexibility and high chemical reaction activity, in addition, the epoxy end-capping reagent recycled in the demonomerization process can be recycled, and the economic benefit and the environmental protection property are further improved.

Acrolein is produced by selectively oxidizing allyl alcohol over a first mixed metal oxide catalyst in the presence of oxygen in the vapor phase. The first mixed metal oxide catalyst comprises oxides of molybdenum and bismuth. Acrylic acid is produced by selectively oxidizing the acrolein over a second mixed metal oxide catalyst in the presence of oxygen in the vapor phase. The second mixed metal oxide catalyst has a different composition from the first mixed metal oxide catalyst.

The present disclosure herein discloses a skeleton supported catalyst and a method for preparing allyl alcohol polyoxyethylene ether by using the same. The skeleton supported catalyst is a catalyst loaded with barium oxide, potassium oxide, yttrium oxide within a copper skeleton. A method comprising: putting the skeleton supported catalyst into a reaction vessel, and after adding nitrogen to the reaction vessel, adding dried and dehydrated allyl alcohol or the allyl alcohol polyoxyethylene ether with low molecular weight to the reaction vessel, raising the temperature, and continuously introducing dried and dehydrated ethylene oxide for reaction; after the reaction being completed, cooling down, and filtering and discharging to obtain after the reaction being completed, cooling down, and filtering and discharging to obtain a finished product of the allyl alcohol polyoxyethylene ether. The allyl alcohol polyoxyethylene ether product prepared by the skeleton supported catalyst of the present disclosure has excellent product performance.

The invention discloses a temperature-resistant and salt-resistant tackifier and a preparation method thereof, and relates to the technical field of fracturing fluids. The preparation method of the temperature-resistant and salt-resistant tackifier comprises the following steps: taking a first monomer and diethanol amine to carry out epoxy ring-opening reaction, and after the reaction is finished, separating and purifying to obtain an intermediate; taking the intermediate, adding a quaternization reagent for quaternization reaction, and then separating and purifying to obtain an active monomer; the first monomer is one of allyl alcohol glycidyl ether, acrylic acid glycidyl ether and methacrylic acid glycidyl ether, and the quaternization reagent is one of halogenated carboxylate or halogenated sulfonate; the preparation method comprises the following steps: dissolving acrylamide, an active monomer and unsaturated phosphate, and carrying out free radical polymerization under the action of an initiator. The tackifier provided by the invention has good temperature-resistant and salt-resistant effects, and can tolerate salt water with mineralization degree of 120,000 mg / L and high temperature of 150 DEG C.

The invention relates to a preparation technology of a multifunctional plastic clothes hanger through cooperation of degradable color master batches and nitrogen filling injection molding, and belongs to the technical field of plastic products. Adding the polylactic acid, the styrene-acrylonitrile copolymer, the modified stone powder, the degradable color master batch and the compound additive into a horizontal helical ribbon mixer, stirring and drying to obtain a mixture; the dried mixture is added into an injection molding machine to be melted and plasticized, a screw pushes melt to be injected into a mold, high-pressure nitrogen is injected into the melt, and the melt is pushed to completely fill a cavity; the plastic clothes hanger is obtained through pressure maintaining, cooling and demolding; the compound additive is prepared from allyl alcohol polyoxyethylene ether, 2-octenyl succinic anhydride, 14-mercaptotetradecanoic acid, anhydrous tetrahydrofuran, 2-hydroxy-4 '-(2-hydroxyethoxy)-2-methyl propiophenone and triethylamine. The preparation method comprises the following steps: preparing the compound additive; the degradable material is adopted, the biodegradation rate is high, the mechanical property is stable, the coloring effect is good, fading is not prone to occurring, and the service life is long.

The invention belongs to an allyl alcohol copolymer, and particularly relates to a method for preparing an allyl alcohol copolymer based on an intermediate conversion method, the allyl alcohol copolymer and application of the allyl alcohol copolymer. The method comprises the following steps: reacting allyl alcohol with a hydroxyl conversion reagent to convert hydroxyl into other groups so as to obtain a new allyl monomer; carrying out copolymerization on the monomer and other comonomers under the action of an initiator to obtain a copolymer; the hydroxyl is recovered by removing a conversion group, so that efficient and green preparation of the allyl alcohol copolymer is realized. The hydroxyl is converted into other groups, so that the reactivity rate of copolymerized monomers is closer during copolymerization, and the regulation and control of molecular weight and molecular composition are easy to realize; the high-temperature and high-pressure reaction conditions are avoided, and the safety risk caused by the fact that the highly toxic allyl alcohol raw material is greatly excessive is avoided; the polymerization reaction can be performed under normal pressure, the reaction condition is mild, and the equipment investment and maintenance cost are reduced; and the amount of residual allyl alcohol in the product is greatly reduced.

The invention relates to the field of coatings, in particular to a coating delustering agent and a preparation process thereof. The preparation process of the delustering agent comprises the following steps: step 1, preparing aminated aluminum silicate powder; step 2, reacting allyl alcohol glycidyl ether with the aminated aluminum silicate powder to obtain activated aluminum silicate powder; and step 3, initiating polymerization reaction by using styrene, dimethyl vinylphosphonate and the activated aluminum silicate powder to obtain modified aluminum silicate powder, namely the coating matting agent. The delustering agent is prepared by taking aluminum silicate as a main base material and carrying out surface modification treatment on the aluminum silicate. Compared with conventional inorganic silicon matting agents, the matting agent prepared by the method is higher in surface activity, more suitable for water-based coatings, more excellent in dispersity and capable of enhancing the impact resistance and the heat and humidity resistance of the coatings to a certain extent on the basis of ensuring the matting rate.

The invention relates to a preparation method of a polysiloxane defoaming composition. The polysiloxane defoaming composition is prepared from silicone grease, a polyether-polysiloxane copolymer, a surfactant and polyether. The silicone grease is prepared from the following raw materials: branched polysiloxane, hydrogen-containing polysiloxane, silicon dioxide, a TQ polymer, an addition catalyst and an inhibitor; the polyether-polysiloxane copolymer is prepared from hydrogen-containing silicon resin with a spatial structure, diallyl alcohol polyether and allyl polyether through a reaction. The polysiloxane defoaming agent composition obtained by the invention has the characteristics of excellent foam control and easiness in cleaning.

The present invention relates to the field of organic synthesis, and more particularly to a method for the oxidation of allylic alcohols to α,β-unsaturated carbonyl compounds in the presence of a zirconium catalyst and a hydrogen acceptor.

Provided is a binder including a polymer having a hydroxyl group, wherein the polymer includes a structural unit derived from an unsaturated carboxylic acid-based monomer, and a structural unit derived from at least one hydroxyl group-containing monomer selected from the group consisting of 2-hydroxyethyl acrylate, allyl alcohol, and isoprenol, the content of the structural unit derived from the hydroxyl group-containing monomer is 5 mol % to 50 mol % based on the total amount of the polymer, the weight average molecular weight of the polymer is 1000 to 5000, and the pH is 6.5 or lower.

The invention relates to the technical field of lubricating oil, and particularly discloses graphene water-based rapier loom gear oil and a preparation method thereof. The graphene water-based rapier loom gear oil provided by the invention is prepared from the following components in parts by weight: 967 to 992 parts of water-soluble polyether polyol, 10 to 15 parts of silicon dioxide, 5 to 8 parts of phosphorus-containing modified graphene oxide, 1 to 5 parts of an anti-wear agent, 1 to 5 parts of an antioxidant and anti-gum agent and 1 to 3 parts of an anti-rust agent, the water-soluble polyether polyol is selected from one or more of polyethylene glycol, polypropylene glycol, an ethylene oxide-propylene oxide copolymer and allyl alcohol polyoxyalkyl ether; furthermore, the silicon dioxide is a mixture of silicon dioxide with the particle size of 10-15 microns, silicon dioxide with the particle size of 300-500 nm and silicon dioxide with the particle size of 50-100 nm. The graphene water-based rapier loom gear oil provided by the invention has very good viscosity-temperature characteristics and extreme pressure wear resistance, and can ensure the operation stability of rapier loom equipment under an extreme pressure condition.

The invention relates to a synthesis method of a branched chain type allyl alcohol compound, which comprises the following steps: under the protection of nitrogen, taking different substituted terminal alkyne and formalin as raw materials, taking metal cobalt salt and an organic ligand as catalysts, taking Hanus ester as a reducing agent, and carrying out a reaction in the presence of an organic solvent and a photosensitizer to obtain the branched chain type allyl alcohol compound. And carrying out illumination reaction to obtain the branched chain type allyl alcohol compound. According to the method, reaction raw materials and reagents are simple and easy to obtain, conditions are mild and easy to control, atom economy is high, precious metal catalysis is not needed, the substrate application range is wide, regioselectivity is high, and wide application prospects are achieved.

The invention belongs to the technical field of organic synthesis, and discloses a preparation method of a 3-alkylindole compound, which comprises the following steps: in an inert atmosphere, reacting a reaction solution mixed with an indole compound, an allyl alcohol compound, a catalyst Mn-1 and alkali at 110-150 DEG C for 12-24 hours to obtain the 3-alkylindole compound. Mn (CO) 5Br is used as a transition metal and complexed with a PNP pincerlike manganese complex to obtain the Mn-1 catalyst, the 3-alkylindole compound is obtained under the catalysis of the catalyst, allyl alcohol can be aryl allyl alcohol or aliphatic allyl alcohol, a substituent group on an indole ring can be an electron withdrawing group, the application range of a substrate is wide, meanwhile, the selection range of alkali or a solvent is wide, and the 3-alkylindole compound is suitable for industrial production. The method has the advantages of high atom economy, environment friendliness, high safety and the like.

The invention discloses a method for synthesizing a polysubstituted trifluoromethyl olefin compound from gem-difluoroallyl alcohol. The preparation method comprises the following steps: in a nitrogen (N2) atmosphere, sequentially adding a gem-difluoroallyl alcohol (R1R2OHCR3C = CF2) compound, acetic anhydride (Ac2O), a solvent dichloromethane (DCM) and a fluorine source pyridine hydrofluoride (Py.9HF) reagent into a 10mL Schlenk tube to obtain a mixture, stirring the mixture at room temperature (rt) until the reaction is finished, filtering, washing and drying to obtain the compound. A crude product obtained by the reaction is subjected to silica gel column chromatography separation to obtain the high-selectivity polysubstituted trifluoromethyl olefin compound. The preparation method disclosed by the invention can be carried out under mild conditions and is simple and convenient to operate, most of the adopted raw materials are simple and easily available or commercialized reagents, the reaction raw materials are easily available, the yield of the target product is high, the functional group compatibility of the product is good, and the application range of a substrate is relatively wide; the obtained polysubstituted trifluoromethyl olefin compound contains a plurality of functional groups such as trifluoromethyl, olefin and the like. The method provides a more efficient and safer new strategy for synthesizing the polysubstituted trifluoromethyl olefin under mild conditions, particularly, metal participation is avoided, a new opportunity is provided for green medicine synthesis, and the method is predicted to have wide application prospects in the fields of medicine research and development, natural product derivative synthesis, life science and the like.

The application discloses an indoor moisture-proof and water-resistant gypsum board and a preparation method thereof, and belongs to the technical field of gypsum board preparation. The preparation method of the indoor moisture-proof and water-resistant gypsum board comprises the following steps: S1, uniformly mixing building gypsum, modified fluorite gypsum, deionized water, a polyester adhesive, a composite water reducing agent, blast furnace slag powder and the like to obtain a gypsum slurry; S2, paving the gypsum slurry on a first layer of cover paper, paving a second layer of cover paper on the gypsum slurry, and performing compaction, final setting, drying and solidification to obtain the indoor moisture-proof and water-resistant gypsum board. The composite water reducing agent is obtained by the reaction of ethyl vinyl ether, trichlorofluoroethylene and allyltrimethoxysilane. The polyester adhesive is obtained by the reaction of allyl alcohol, phthalic anhydride and triallyl cyanurate. The prepared gypsum board not only has good moisture-proof and water-resistant performance, but also has good mechanical properties, thereby prolonging the service life and ensuring the quality of the gypsum board to a certain extent.

The present application relates to the technical field of organic synthesis, and particularly relates to a method for preparing (+)-crispine A by means of biological enzyme resolution. First, 6,7-dimethoxy-3,4-dihydroisoquinoline-2-oxide is subjected to 1,3-dipolar cycloaddition with allyl alcohol to obtain a first compound; then the first compound is added into a sulfonylation reagent and zinc powder to obtain a racemate second compound through a three-step continuous series reaction of primary alcohol sulfonylation, nitrogen-oxygen bond cleavage and ring formation; then the second compound is mixed with vinyl acetate and biological enzyme, and chiral resolution is carried out under the action of the biological enzyme to obtain a third compound with right-handed optical rotation and a fourth compound with left-handed optical rotation; finally, the third compound is mixed with an alkaline reagent and a sulfonylation reagent, and then secondary alcohol sulfonylation is carried out to obtain a fifth compound with right-handed optical rotation; the fifth compound is mixed with a deoxidizing reagent to carry out deoxidation reaction, and (+)-crispine A is prepared. The method is simple, green and environmentally friendly, and can be produced in large quantities.

The present invention relates to the technical field of organic synthesis. Disclosed is a method for synthesizing allyl alcohol. The synthesis method comprises the following steps: adding a water-soluble acid-resistant high-boiling-point organic solvent to an aqueous allyl acetate solution and stirring the mixture to form a homogeneous solution; then heating the homogeneous solution, and performing a hydrolysis reaction under the action of a solid acid catalyst to obtain a mixture solution containing allyl alcohol; and then distilling the mixture solution to separate out the high-boiling-point organic solvent to obtain a crude allyl alcohol product. The synthesis method provided by the present invention can significantly improve the single-pass hydrolysis conversion rate of allyl acetate at low costs and achieve efficient and continuous industrial production of allyl alcohol. Moreover, the method can realize the separation of allyl alcohol from the high-boiling-point organic solvent simply by means of a simple distillation separation process. The separated organic solvent has high purity and light color and can be reused. The method has no waste liquid and waste residue generated.

The invention discloses a preparation method of a cyanoborate lithium salt derivative, which comprises the following steps: 1, mixing an alcohol compound, a lithium source compound, a boron source compound and trimethylsilyl cyanide in a polar organic solvent, and filtering after complete reaction to obtain a cyanoborate crude product filtrate; the alcohol compound is selected from one of 2, 2, 2-trifluoroethanol, 2, 2-difluoroethanol, 2-fluoroethanol, 3-hydroxypropionitrile, allyl alcohol and propargyl alcohol; the lithium source compound is selected from one of lithium carbonate and lithium hydroxide; the boron source compound is selected from one of boric acid, diboron trioxide and boron tribromide; the reaction temperature is controlled to be 0-120 DEG C; and 2, adding an inert organic solvent into the cyanoborate crude product filtrate for crystallization, and performing vacuum drying to obtain a finished product of the cyanoborate lithium salt. The method has the advantages of high yield and purity, simple process, convenience in operation and low cost, and is extremely suitable for industrial production.

The invention provides a method for preparing allyl alcohol through epoxypropane isomerization, and relates to the technical field of chemical synthesis. According to the method, propylene oxide is subjected to an isomerization reaction in the presence of a polymerization inhibitor to prepare allyl alcohol; wherein the polymerization inhibitor is a phenol polymerization inhibitor and / or a quinone polymerization inhibitor. The technical scheme of the invention can effectively reduce the deactivation rate of the catalyst and prolong the service life of the catalyst. The method for preparing allyl alcohol through epoxypropane isomerization is high in production efficiency and low in production cost, and has important industrial application value.

The invention relates to the technical field of preparation of allyl alcohol polyether, in particular to a preparation method of allyl alcohol random polyether. According to the method, allyl alcohol is used as an initiator and is subjected to a polymerization reaction with ethylene oxide and epoxypropane in the presence of a non-metal organic catalyst. The method comprises the following steps: firstly, activating a mixed solution of part of ethylene oxide and propylene oxide, an initiator and a catalyst, then continuously dropwise adding the residual mixed solution into a sealed reaction system for growth polymerization, and finally recovering the catalyst through reduced pressure distillation to directly obtain a high-purity product. The method is simple in process route, avoids complex post-treatment steps such as neutralization and adsorption required by using a noble metal or sodium alcoholate catalyst, is high in catalyst recovery rate, extremely low in potassium and sodium ion content (less than or equal to 3ppm) in the product, and capable of accurately regulating and controlling the molecular weight in a range of 1400-3100, remarkably reduces the production cost, and is suitable for industrial production.

The invention relates to the field of organic materials, in particular to a method for producing diallyl terephthalate by utilizing PET (Polyethylene Terephthalate). The method for producing diallyl terephthalate by using PET provided by the invention comprises the following steps: mixing PET, allyl alcohol and a catalyst, and heating for reaction to obtain diallyl terephthalate. According to the method disclosed by the invention, upgraded recovery from waste PET to a high-value optical monomer is realized, meanwhile, the method is a low-cost and high-environmental-benefit diallyl terephthalate synthesis method, and the generation cost of diallyl terephthalate is reduced.

The present invention belongs to the technical field of polyurethane synthetic leather, and specifically relates to a reactive feel agent, a preparation method thereof, and an application. The reactive feel agent provided by the present invention comprises a dihydroxy-terminated silicone oil, oleic acid amide, and erucic acid amide; the dihydroxy-terminated silicone oil is obtained by a condensation reaction of a hydrogen-terminated silicone oil and an allyl alcohol polyether; the mass percentage of the erucic acid amide in the dihydroxy-terminated silicone oil is ≤10%; the mass percentage of the oleic acid amide in the dihydroxy-terminated silicone oil is ≤10%. The reactive feel agent provided by the present invention utilizes the dihydroxy-terminated silicone oil to introduce a polysiloxane chain segment into the polyurethane molecular structure through a chemical bond. By compounding a small amount of oleic acid amide and erucic acid amide, while not affecting the reaction activity of the dihydroxy-terminated silicone oil, an ideal comprehensive feel can be provided, that is, a touch effect similar to that of baby skin with elasticity, fullness, and softness.

The invention discloses a preparation method of a low-pore-number composite lining, and belongs to the technical field of textiles. The preparation method of the low-hole-number composite lining comprises the following steps: (1) weaving polyester yarns into gray fabric; (2) shaping and preshrinking the gray fabric; (3) dyeing the set and pre-shrunk gray fabric; (4) shaping and finishing the dyed gray fabric to obtain a composite lining; wherein the dye for dyeing is obtained by reacting N-amino-4-N, N-dimethyl-1, 8-naphthalimide with ferrocene dicarboxaldehyde, and the dye for dyeing is obtained by reacting N-amino-4-N, N-dimethyl-1, 8-naphthalimide with ferrocene The setting agent for setting and finishing contains a hydrophilic softening agent, the hydrophilic softening agent is obtained by mixing polyether phenyl silicone oil with a compound emulsifier and deionized water, and the polyether phenyl silicone oil is obtained by reacting side chain hydrogen-containing silicone oil, allyl alcohol polyoxyalkyl ether, vinyltriethoxysilane and 1-(4-vinyl-phenyl)-ethanone; the prepared low-hole-number composite lining is good in hydrophilicity, color fastness and softness.

The invention relates to the technical field of medical material preparation, and particularly discloses a shape memory composite material for a uterus support and a preparation method thereof.The shape memory composite material is prepared by adding 1, 4-butylene glycol into raw materials for synthesizing polyurethane, introducing a double-bond functional group into the structure of a polyurethane elastomer and meanwhile modifying nano silicon dioxide; a double-bond functional group is introduced to the surface of nano silicon dioxide, and double-bond crosslinking is realized through ultraviolet radiation, so that the shape memory composite material is obtained and has good mechanical properties and deformation recovery rate; allyl alcohol glycidyl ether is used for modifying nano silicon dioxide, the compatibility of nano silicon dioxide and a material matrix is improved, meanwhile, allyl alcohol glycidyl ether serves as a flexible chain segment to be introduced into the shape memory composite material, and after the material is subjected to external force, the flexible chain segment can be used for modifying the nano silicon dioxide. Energy can be effectively absorbed and can be quickly recovered after the external force is relieved, so that the deformation recovery rate of the material is increased.

An organic silicon resin toughening agent, a single-component high-strength epoxy structural adhesive, and the preparation method thereof. The organic silicon resin toughening agent is prepared by reacting epoxy modified hydrogen-containing silicone oil with vinyl six-membered cyclic oligomeric silsesquioxane; The epoxy modified hydrogen-containing silicone oil is prepared by reacting allyl alcohol glycidyl ether with dihydrogen-terminated hydrogen-containing silicone oil. The organic silicon resin toughening agent with a circular network structure unit synthesized by the present disclosure has better high and low temperature resistance compared to toughening agents such as nitrile rubber and core-shell structure rubber. While improving the toughness of single-component high-strength epoxy structural adhesive, it can significantly enhance the high and low temperature resistance of single-component high-strength epoxy structural adhesive.

A process for co-feeding gaseous ethylene and liquid allyl alcohol in the presence of a catalyst to produce 1,4-butanediol and n-propanol may comprise: introducing a gaseous mixture of ethylene, carbon monoxide, and hydrogen in a solvent into a reactor in the presence of a hydroformylation catalyst; introducing liquid allyl alcohol (AA) into the reactor; and conducting a hydroformylation reaction at a temperature between 50° C. and 100° C. to obtain a hydroformylation product.

The invention discloses a preparation method of a silicone oil modified polyether defoaming agent, which is characterized in that alkynol (EO / PO type) block polyether and allyl alcohol (PO / EO type) block polyether are subjected to addition reaction under the action of a catalyst to generate the silicone oil modified polyether defoaming agent. The silicone oil modified polyether defoaming agent disclosed by the invention has the characteristics of high foam breaking speed and long foam inhibition period; the defoaming agent provided by the invention has the advantages of high temperature resistance, excellent chemical stability and excellent compatibility, and compared with a traditional polyether defoaming agent, the defoaming agent provided by the invention can achieve a better defoaming effect under the condition of a relatively low addition amount.

Provided is a method for producing 4-hydroxybutyramide represented by formula (1), which comprises a reaction step in which allyl alcohol, a primary amine represented by R-NH2 (R is a hydrocarbon group having 1-20 carbon atoms), and carbon monoxide are reacted in the presence of a rhodium or cobalt-containing catalyst. (In formula 1, R represents a hydrocarbon group having 1-20 carbon atoms. > # imgabs0 #