102results about How to "Reduced hydration rate" patented technology

An embolization device for occluding a body cavity includes one or more elongated, expansible, hydrophilic embolizing elements non-releasably carried along the length of an elongated filamentous carrier that is preferably made of a very thin, highly flexible filament or microcoil of nickel / titanium alloy. At least one expansile embolizing element is non-releasably attached to the carrier. A first embodiment includes a plurality of embolizing elements fixed to the carrier at spaced-apart intervals along its length. In second, third and fourth embodiments, an elongate, continuous, coaxial embolizing element is non-releasably fixed to the exterior surface of the carrier, extending along a substantial portion of the length of the carrier proximally from a distal tip, and optionally includes a lumenal reservoir for delivery of therapeutic agents. Exemplary methods for making these devices include skewering and molding the embolizing elements. In any of the embodiments, the embolizing elements may be made of a hydrophilic, macro-porous, polymeric, hydrogel foam material. In the second, third and fourth embodiments, the elongate embolizing element is preferably made of a porous, environmentally-sensitive, expansile hydrogel, which can optionally be made biodegradable and / or bioresorbable, having a rate of expansion that changes in response to a change in an environmental parameter, such as the pH or temperature of the environment.

The invention discloses a high-performance polycarboxylate water reducing agent. The polycarboxylate water reducing agent has a structural general formula shown as a structural formula (I). The invention further provides a preparation method of the high-performance polycarboxylate water reducing agent. Apart from a polyether macromonomer and an unsaturated carboxylic acid monomer, an unsaturated phosphate monomer is added to obtain a product, namely, the high-performance polycarboxylate water reducing agent having a phosphate structure. The polycarboxylate water reducing agent disclosed by the invention is safe and simple in preparation process, environmentally friendly, low in energy consumption, low in cost, and suitable for industrial large-scale production. In the structural formula (I), R1 is -H, -COO- or -CH2COO-; R2 is -H or -CH3; R3 is -H or -CH3; R4 is -H or -CH3; R5 is -H or -CH3; R6 is -CH2- or -CH2CH2-; X, Y, Z and n are integers; X=1-100; Y=1-100; Z=1-100; and n=22-53.

An embolization device for occluding a body cavity includes one or more elongated, expansible, hydrophilic embolizing elements non-releasably carried along the length of an elongated filamentous carrier that is preferably made of a very thin, highly flexible filament or microcoil of nickel / titanium alloy. At least one expansile embolizing element is non-releasably attached to the carrier. A first embodiment includes a plurality of embolizing elements fixed to the carrier at spaced-apart intervals along its length. In second, third and fourth embodiments, an elongate, continuous, coaxial embolizing element is non-releasably fixed to the exterior surface of the carrier, extending along a substantial portion of the length of the carrier proximally from a distal tip, and optionally includes a lumenal reservoir for delivery of therapeutic agents. Exemplary methods for making these devices include skewering and molding the embolizing elements. In any of the embodiments, the embolizing elements may be made of a hydrophilic, macroporous, polymeric, hydrogel foam material. In the second, third and fourth embodiments, the elongate embolizing element is preferably made of a porous, environmentally-sensitive, expansile hydrogel, which can optionally be made biodegradable and / or bioresorbable, having a rate of expansion that changes in response to a change in an environmental parameter, such as the pH or temperature of the environment.

The invention discloses a desulfurizing plaster self-leveling material, which main component weight percent are as follows: 30-65% desulfurizing plaster, 25-60% high-alumina cement, 0-30% ordinary portland cement, 0-20% fly ash, 0-8.0% redispersing emulsion powder. The material comprises an amount of additive and fine aggregate. Blending each component at determined weight percent fully and uniformly in a blender, packing to get self-leveling material. The invention can prepare self-leveling material by desulfurizing plaster massively, has more simple manufacturing technique, less energy consumptions, low cost, moderate coagulation time, strong and better water resistance, microswelling performance, can be widely applied to kinds of leveling execution.

The invention provides a method for preparing hydrated adhesive, which solves the problems of disposable usage, difficultly-controlled pasting position, difficult removal and the like in the traditional tackifier fundamentally. The technical key points of the invention are as follows: the hydrated adhesive is prepared by mixedly stirring the following raw materials by weight percent at normal temperature and pressure: 10%-35% of sodium alga acid (C6H7O8Na), 5%-30% of competed hydrate, 20%-50% of water-soluble adhesive and 5%-65% of water. The hydrated adhesive in the invention has the advantages of controllable viscosity, stable physicochemical property, environment protection, capability of repeated use, no residual and the like, and is suitable for caking of solid materials such as various paper, plastic and the like.

The invention provides a preparing method for polycarboxylate water reducing agent. The polycarboxylate water reducing agent composed of, by weight, 30%-55% of deionized water, 35%-50% of polyoxyethylene ether, 5%-10% of carboxylic acid derivatives monomer, 0.0005%-0.002% of catalyst, 1.5%-4.5% of initiator, 0.2%-0.8% of chain transfer agent, 1.0%-2.5% of structure modifying agent and 4.5%-8.5% of alkali liquor. Under the temperature of 20-35 DEG C, the deionized water and the polyoxyethylene ether are enabled to be put in a reaction still to be dissolved, after the deionized water and the polyoxyethylene ether are fully dissolved, the carboxylic acid derivatives monomer, the catalyst, the initiator, the chain transfer agent and the structure modifying agent are enabled to be added in sequence, after stirring for 28-32 minutes, the mixed liquor still standings for 4-6 hours under room temperature, the alkali liquor is added in under a state of stirring, a potential of hydrogen (PH) value is adjusted to be 6.0-7.5, and then products are achieved.

The invention provides a preparation method of a slushing agent for concrete. The preparation method comprises the following steps in sequence: implementing the first reaction between maleic anhydride and hydroxypropyl methyl cellulose in glacial acetic acid under the catalysis of acetate, so as to obtain the hydroxypropyl methyl cellulose monomaleate; and carrying out free radical polymerization between methyl allyl polyoxyethylene ether, acrylic acid solution and hydroxypropyl methyl cellulose monomaleate under an oxidentive-reductive initiation system, so as to obtain the slushing agent for concrete. According to the slushing agent for concrete, prepared by the preparation method provided by the invention, the molecular structure contains the hydroxypropyl methyl cellulose molecular structure unit, so that the macromolecules of the slushing agent can be entangled with each other to form a net-shaped structure to wrap cement and water for effectively preventing the moisture in the mortar from evaporating, and as a result, the slump keeping property is good. The invention also provides the slushing agent for concrete, and the slushing agent for concrete has the structure as shown in formula (1).

The invention discloses a crosslinking-type low-sensitivity ester-ether copolymerized polycarboxylate superplasticizer and a preparation method thereof. The crosslinking-type low-sensitivity ester-ether copolymerized polycarboxylate superplasticizer has the number-average molecular weight of 10000-100000 and has a structural formula as shown in the specification. Under the synergistic effect of various groups, the polycarboxylate superplasticizer formed by copolymerization of 4-hydroxybutyl-vinyl polyoxyethylene ether, unsaturated acid, unsaturated phosphomonoester and unsaturated phosphodiester has the advantages of high water-reducing rate, high slump loss resistance, high peaceability, mud-resistant property and low dosage sensibility.

The invention relates to an oil well cement high temperature retarder applied to the technical field of oil field well drilling and completion. The invention is characterized in that: the retarder is composed of 1 part by weight of water, 0.005-0.030 part by weight of hydroxycarboxylic acid and salt thereof, 0.005-0.010 part by weight of cellulose derivative and 0.0001-0.0010 part by weight of sulfonate. The high temperature retarder has wide applicable temperature range, can be applied to cement paste systems with various densities, has strong compatibility with a plurality of admixture systems, and does not influence the performance of cement paste. The cement paste prepared by the retarder is stable, the thickening transition time is short, and the thickening time is adjustable; the hardened cement paste has rapidly developed compression strength and is suitable for the requirement of well cementation engineering.

The invention discloses an antifatigue basic magnesium sulfate cement which is composed of the following components in percentage by mass: 42-58% of magnesium oxide, 18-25% of magnesium sulfate heptahydrate, 10-15% of industrial waste residue powder, 5-13% of white slag, 3-5% of mineral admixture, 4-6% of straw, 2-4% of desulfurized gypsum, 3-5% of fly ash and 1-2% of thickening time control agent. The appropriate additives are added into the magnesium oxysulfate cement to form a new basic magnesium sulfate phase and generate the antifatigue basic magnesium sulfate cement which has completely different properties and characteristics from the traditional magnesium oxysulfate cement. The main hydration product is high-strength 517 whisker. The antifatigue basic magnesium sulfate cement belongs to novel special cement which has the advantages of whisker self-formation, high strength, high toughness, high folding ration, carbonization resistance, salt resistance, hydrothermal resistance, seawater resistance, impact resistance, fatigue resistance, reinforcing steel rust resistance, high durability and long service life.

The invention discloses seepage-scouring-resistant concrete and a preparation method thereof. The seepage-scouring-resistant concrete comprises the following components: cement, water, fly ash, silicafume, a fine aggregate, a coarse aggregate, an additive, a preservative and ground mineral powder; wherein the coarse aggregate comprises granite and basalt at a mass ratio of 1: (1.5-1.8); the additive comprises an expanded fiber anti-cracking waterproof agent, an air entraining agent and a water reducing agent at a mass ratio of 1: (0.3-0.5): (0.5-0.7); the preservative is prepared from the following raw materials in parts by weight: 2 to 5 parts of isobutyltriethoxysilane, 1.2 to 1.6 parts of eleostearic acid, 0.8 to 1.6 parts of barium nitrate, 0.5 to 1 part of 2BaO*SiO2 and 3 to 7 partsof polyurethane resin. The seepage-scouring-resistant concrete has the advantages of seawater seepage erosion resistance, strong corrosion resistance and good durability.

The invention discloses a bending-resistant basic magnesium sulfate cement. The cement is composed of the components of, by mass, 40-55% of magnesium oxide, 20-25% of magnesium sulphate heptahydrate, 10-20% of industrial waste powder, 5-9% of white slag, 3-8% of a mineral admixture, 2-5% of desulfurization gypsum, 2-4% of straw, and 1-3% of a coagulation adjustment agent. According to the invention, appropriate additives are added into magnesium oxysulfate cement, such that a novel basic magnesium sulfate phase is formed, and the bending-resistant basic magnesium sulfate cement with performances and characteristics completely different than those of the traditional magnesium oxysulfate cement is produced. A main hydration product of the basic magnesium sulfate cement is high-strength 517 whiskers. The cement is a novel special cement with the advantages of whisker self-formation, high toughness, high compressive-bending strength ratio, carbonization resistance, bittern resistance, hydrothermal resistance, seawater resistance, impact resistance, fatigue resistance, carbonization resistance, steel bar corrosionresistance, high durability, and long service life.

A multilayer film has a first layer and a second layer. The first layer comprises an additive, a binder, and a crosslinking agent. The additive is a flavor, fragrance, colorant, antimicrobial agent, antioxidant, chelating agent, and / or odor absorbent. The binder is a polysaccharide and / or a protein. The crosslinking agent comprises a compound with at least two carbonyl groups. The second layer comprises a non-water-soluble thermoplastic polymer comprising at least one member selected from the group consisting of polyolefin, polyamide, polyester, polyvinylidene chloride, polyvinyl chloride, and polystyrene. Each of the additive, binder, and crosslinking agent are present throughout a thickness of the first layer. Preferably, the first layer is coated onto the second layer, which is preferably a non-water-soluble thermoplastic polymer, e.g., polyolefin, polyamide, and / or polyester. The film is especially useful for cook-in applications, in which a food product (preferably comprising uncooked meat) is packaged in the film with the coated layer against the meat. The meat is then cooked and the additive transfers to the meat, and purge can be very low. The invention also pertains to a process for preparing a cooked food product, process for making a coated film, and articles formed from the film, such as bags and casings.

The invention discloses a preparation method of a cross-linked viscosity-reducing polycarboxylate water reducer. The preparation method comprises the following steps: (1) preparing esterification monomers; (2) performing the copolymerization reaction; and (3) performing the neutralization reaction. According to the preparation method of the invention, allyl alcohol monomers are copolymerized withesterification monomers obtained by esterifying two or three carboxyl groups in little 2-butane phosphate-1,2,4-tricarboxylic acid, polyether macro momoners, 2-methyl allyl oxyethyl phosphorylcholineand unsaturated acid prepare the cross-linked viscosity-reducing polycarboxylate water reducer, and while phosphate, carboxylate radicals, quaternary ammonium salt and ester groups are introduced intoa polymer molecular structure, the polymer structure is slightly cross-linked. The cross-linked viscosity-reducing polycarboxylate water reducer prepared by the method has viscosity reducing performance, also has water reducing, slump loss resisting and mud resisting properties, and solves the problems of high viscosity, poor mixing property and fast loss due to high mud content in a concrete rawmaterial.

The invention discloses carbonation-resistant basic magnesium sulfate cement. The carbonation-resistant basic magnesium sulfate cement is prepared from the following components in percentage by mass: 40 to 55% of magnesium oxide, 20 to 25% of magnesium sulfate heptahydrate, 10 to 20% of industrial waste residue powder, 5 to 9% of white slag, 3 to 8% of mineral admixtures, 2 to 4% of desulfurization gypsum, 6 to 8% of mineral slag, 2 to 4% of straws, 1 to 3% of silica fume and 1 to 3% of adjustable solidification agent. Proper additives are added in magnesium oxysulfate cement to form a novel basic magnesium oxysulfate phase; the carbonation-resistant basic magnesium sulfate cement with totally different property and performance from traditional magnesium oxysulfate cement is produced; the main hydration product of the basic magnesium sulfate cement is 517 crystal whisker; the carbonation-resistant basic magnesium sulfate cement is novel special cement with features of self-formed crystal whisker, high intensity, high toughness, high ratio of compressive strength, carbonation resistance, brine resistance, hydrothermal resistance, seawater corrosion resistance, shock resistance, antifatigue, corrosion of steel bar resistance, high durability and long service life.

The invention discloses a high-temperature-resistant stone powder adsorption-resistant slump-retaining polycarboxylate superplasticizer and a preparation method thereof. The polycarboxylate superplasticizer is prepared from the following components in parts by weight: 320 to 360 parts of unsaturated polyether macromonomer, 20 to 30 parts of unsaturated monocarboxylic acid, 6 to 10 parts of maleimide alkyl acid, 5 to 8 parts of unsaturated phosphate, 2 to 5 parts of unsaturated amino acid monoester, 2.5 to 5.0 parts of oxidant, 0.5 to 1.0 part of reducing agent and 1 to 3 parts of chain transfer agent. The pH value of the water reducing agent is 5.0-7.0, and the solid content of the water reducing agent is 40%-42%. The polycarboxylic acid water reducing agent can effectively solve the problems of insufficient initial fluidity of concrete, too fast slump loss and poor workability of a concrete mixture caused by incapability of simultaneously meeting high temperature resistance and limestone powder adsorption resistance of the existing water reducing agent, and has great significance in widening the engineering application field of the water reducing agent.

The invention discloses anti-corrosion and anti-rust concrete and a preparation method thereof. The anti-corrosion and anti-rust concrete is prepared from the following components in parts by weight:270-290 parts of cement, 60-70 parts of mineral powder, 70-90 parts of fly ash, 673-727 parts of sand, 950-970 parts of stone, 111-165 parts of water and 30-40 parts of additives. The additives comprise a pumping agent and an anti-corrosion and anti-rust agent, and the anti-corrosion and anti-rust agent comprises the following components in parts by weight: 5-9 parts of modified epoxy resin, 1-5 parts of a GWZB820 type reinforcing agent, 1.5-3.5 parts of eleostearic acid, 2.3-3.1 parts of 2BaO. SiO2, 3.2-4.8 parts of polymeric aluminum phosphate, 2.6-3.4 parts of water glass, 1.5-3.5 parts ofsodium molybdate and 1.8-2.6 parts of didecyl dimethyl ammonium chloride. The anti-corrosion and anti-rust concrete has the advantages of being good in anti-corrosion and anti-rust effect, excellent in durability and high in heat preservation and heat insulation performance.

The invention relates to the technical field of building additives, and especially relates to a preparation method of a modified starch ether for prolonging opening time of ceramic tile glue. The preparation method comprises the following steps: (1) chemical modification: mixing starch, an alkalizing agent, an alcohol and an inhibitor, adding a plurality of etherifying agents, controlling etherifying reaction temperature to be 10-90 DEG C and reaction time to be 2-20 hours, and carrying out chemical modification to obtain an etherified starch; and (2) physical modification: mixing the etherified starch prepared in the step (1), a thickening agent, a retarder and a water reducing agent for a certain time, and carrying out physical modification. The modified starch ether prepared by the preparation method is applied in ceramic tile glue, can greatly improve the adhesive property of ceramic tiles and remarkably prolong the opening time, and the above effect is difficult to be achieved byusing existing starch ether products and methods.

The invention discloses indoor gypsum plaster and a preparation method thereof. The gypsum plaster comprises, by weight, 40-50 parts of hemihydrate gypsum cementing material, 10-16 parts of diatom ooze, 5-8 parts of calcium powder, 40-60 parts of talcum powder, 0.05-0.10 part of methyl cellulose, 0.4-0.8 part of calcium sulfate, 1.5-3.5 parts of nano titanium dioxide particle, 2.5-6.5 parts of nano silicon dioxide particle, 0.05-0.06 part of retarder, 2.5-4.5 parts of dispersible latex powder, 1.5-2 parts of sodium hydrogen sulfate, 3-10 parts of graphene and 0.5-1.2 parts of auxiliary materials. The indoor gypsum plaster has the advantages that the performance such as the compressive strength, the fracture strength, the water retaining rate and the bonding strength of the gypsum plaster is increased by adding the graphene, the service life of the gypsum plaster is prolonged, and the use stability of the gypsum plaster is increased.

The invention belongs to building materials, and particularly relates to light plastering anhydrite which comprises, in 100 parts by weight, 65-80 parts of high-strength anhydrite powder, 4-20 parts of heavy calcium carbonate, 9-20 parts of glass beads, 1-8 parts of methylcellulose, 0.2-5 parts of guar gum mixture and 0.3-4 parts of cassava pregelatinized starch. Raw materials are accurately screened, proportions are scientifically calculated, production technologies are stable and mature, and constructability is strong. The light plastering anhydrite definitely becomes a special green environment-friendly plastering material for novel walls and ceilings in the future, and can be widely applied.

The invention discloses a retarder for sulphate aluminum cement and a use method thereof. The retarder is prepared from the following raw materials in parts by weight: 30-70 parts of polymer emulsion, 10-25 parts of metylchloro isothiazolinone, 2-10 parts of film-forming agent, 1-15 parts of water reducer and 5-15 parts of polyethylene glycol. The invention also discloses the use method for the retarder. The retarder disclosed by the invention can effectively reduce the coagulation speed of the sulphate aluminum cement; the initial setting time and the final setting time both can be prolonged for above 30min; the fluidity of the cement slurry can be obviously promoted; the fluidity of cement paste can be increased by above 15%. The retarder disclosed by the invention has no any adverse effect to the development of the cement strength, is low in cost, is high in performance stability and is easily stored and transported.

The invention discloses a method for preparing a phosphate functional monomer by a P2O5 dispersion method and application. The invention relates to a method for synthesizing a phosphate functional monomer by feeding a polymerizable unsaturated organic compound dispersed P2O5, wherein a polymerizable unsaturated organic compound dispersing agent used in a synthesis process can participate in a subsequent polymerization reaction, thereby solving the problems of difficult separation and recovery of a low-boiling-point and toxic organic solvent adopted in a preparation process of an existing phosphate functional monomer and environmental pollution, and simultaneously simplifying the synthesis route of the phosphate functional monomer. The invention also discloses a method for preparing a high-performance polycarboxylate superplasticizer by taking a phosphate functional monomer solution with a polymerizable unsaturated organic compound as a solvent as a third monomer of a polycarboxylate superplasticizer, so that the problem of contradiction between dispersion capacity and slump retention capacity of an existing polycarboxylate superplasticizer is solved, and a method for preparing a high-performance polycarboxylate superplasticizer with high dispersion and slump retention capacity and strong cement adaptability is provided.

The invention relates to a gelatinizer including the following components, by weight: 30-350 parts of magnesium- and aluminum-rich silicate (Mg5Si8O20(OH)2(OH2)4.4H2O), 80-150 parts of high-activity aluminum silicate, 5-15 parts of boric acid (H3BO3), 5-15 parts of citric acid (C6H8O7), 2-15 parts of phosphoric acid (H3PO4), 5-10 parts of silicon sol (SiO2.nH2O), 1-3 parts of a siloxane waterproof agent, 800-1200 parts of light calcined magnesium oxide, 300-500 parts of magnesium chloride hexahydrate, 80-120 parts of magnesium sulfate heptahydrate, and 400-600 parts of water. The gelatinizer, on the basis of maintaining the technical indices, such as fireproof performance, waterproof performance and the like, is free of formaldehyde when being used for cementing and adhering various building decorative materials, so that the gelatinizer increases utilization rate of house, provides a green and environment-friendly living environment, and is beneficial to body health of residents.

The invention discloses a retarder for a high-temperature-resistant cement paste system. The retarder comprises the following components: monomers consisting of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, maleic acid and itaconic acid in a mass ratio of (18-24): (9-21): (6-12): (6-12); an initiator accounting for 6%-8% of the total mass of the monomers; and monomer borax accounting for 3%-5% of the total mass of the monomers. A polymer formed by the above components is a quadripolymer which solves the problem of rapid hydration of cement paste at a high temperature; and the quadripolymer synthesized by using a simple synthetic process has better retarding effect compared with the same mass of a terpolymer or bipolymer.

The invention provides self-compacting C120 premixed dry concrete and a preparation method thereof, and belongs to the technical field of concrete materials. The self-compacting C120 premixed dry concrete is prepared from the following components in parts by weight: 480-550 parts of Portland cement, 40-55 parts of coarse aggregate, 70-80 parts of steel fiber, 470-550 parts of fine aggregate, 11-15parts of admixture and 145-190 parts of mineral admixture. According to the premixed dry material concrete prepared by the invention, the compressive strength is not lower than 120MPa, the breaking strength is not lower than 20MPa and the axial tensile strength is not lower than 8MPa after 28d, and after the premixed dry material concrete is transported to a construction site and is directly mixed with water, the self-compaction and vibration-free functions can be realized immediately after discharging, and the premixed dry material concrete has high strength and durability.

The invention discloses a viscosity-reducing type polycarboxylic acid water reducing agent preparation method, which comprises: (1) preparing an esterification monomer; (2) carrying out a copolymerization reaction; and (3) carrying out a neutralization reaction. According to the present invention, the viscosity-reducing type polycarboxylic acid water reducing agent is prepared by co-polymerizing 2-allyloxyethanol, a blend, VPEG, 2-methacryloyloxyethyl phosphorylcholine and an unsaturated acid, such that the phosphate radical, the carboxylate radical, the quaternary ammonium salt and the estergroup are introduced into the molecular structure of the polymer while the polymer structure is lightly cross-linked, wherein the product obtained by the esterification of the single carboxy in 2-phosphonobutane-1,2,4-tricarboxylicacid prepared by a 2-phosphonobutane-1,2,4-tricarboxylicacid esterification reaction, the product obtained by the esterification of the two carboxy in a small amount of2-phosphonobutane-1,2,4-tricarboxylicacid and the product obtained by the esterification of the three carboxy in a small amount of 2-phosphonobutane-1,2,4-tricarboxylicacid form the blend; and the prepared viscosity-reducing type polycarboxylic acid water reducing agent has advantages of viscosity reducing, water reducing, slump retaining and mud resistance, and can solve the problems of high viscosity, poor workability and rapid loss due to the high mud content in the current concrete raw materials.

The invention provides a dry plastering technology. The dry plastering technology comprises the following steps that solid materials and water are blended into ardealite mortar, wherein the solid materials are prepared from, by weight, 600-700 parts of ardealite, 300-400 parts of aggregates, 0.2-1.5 parts of redispersible latex powder, 0.2-0.3 part of a foaming agent, 1-1.5 parts of cellulose ether, 2 parts of a water reducing agent and 1-1.5 parts of a retarder; the ardealite mortar is painted on a base layer to be plastered. The dry plastering technology has the advantages of saving water, time and labor and the like.

The invention relates to a sulphoaluminate cement composite reinforcing agent. The agent is prepared from, by weight, 0.005-0.01 part of stabilizer, 0.1-0.3 part of calcium increasing agent and 0.1-0.3 part of regulating agent. According to the sulphoaluminate cement composite reinforcing agent, through the synergistic effect of the three components, the hydration of sulphoaluminate cement and theformation of ettringite are promoted, the compact type of a hardened slurry structure is kept at the same time, and therefore the sulphoaluminate cement has high later strength.

The invention provides a shaddock peel extract liquid magnesium oxide retarder and application thereof. The magnesium oxide retarder is obtained by the following steps: washing shaddock peel, choppingthe treated shaddock peel, adding alcohol for extraction, filtering to obtain an extract, heating and concentrating the extract to obtain the retarder. Compared with the existing retarders such as hydroxycarboxylic acid and salts thereof, the magnesium oxide retarder is environmentally friendly, low in price, simple in preparation, safe and non-toxic, has a significant retarding effect, and can significantly prolong the setting time.

The invention discloses a novel CO2EGS mode high-temperature corrosion-resistant well cementation cement system for hot dry rock, which belongs to the technical field of oil and gas well cementation and is composed of the following raw materials in percentage by weight: 75-88% of cement with low hydration heat or cement with low calcium-silicon ratio, 11-20% of a high temperature strength enhancer, and 1-5% of an anti-CO2 corroding material. The high-temperature corrosion-resistant well cementation cement system for the hot dry rock has the advantages that the high-temperature corrosion-resistant well cementation cement system for the hot dry rock has corrosion resistance, high-temperature resistance and heat preservation performance at the same time, the requirements of long-term sealingand energy consumption reduction of a hot dry rock production well in a novel CO2-EGS mode can be met, and guarantee is provided for exploration and development, efficient production and environmentalprotection.