347 results about "Crystallization temperature" patented technology

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

The invention discloses a preparation method of a neodymium-yttrium-iron-boron magnet with core-shell heterostructure crystal grains. The method comprises the following steps: preparing neodymium-yttrium-iron-boron rapid-quenching amorphous strips with different yttrium contents through a melting rapid-quenching technology; carrying out crystallization annealing on the amorphous rapid quenching belt at different temperatures, and preparing powder particles with the particle size of 2-5 microns through hydrogen demolishing and jet milling; and the neodymium-yttrium-iron-boron magnet with the core-shell heterostructure is prepared through high-temperature vacuum sintering after orientation forming and cold isostatic pressing of the neodymium-yttrium-iron-boron magnet in a magnetic field. According to the method, dynamic adjustment of distribution of yttrium in a crystal grain core-shell area is achieved by controlling the crystallization temperature of an amorphous rapid quenching zone, and therefore the coercive force of the magnet is improved.

The invention discloses a low-temperature phase change energy storage material and a preparation method thereof, and relates to the technical field of cold storage materials. The provided organic phase-change material is formed by jointly matching alkane and fatty alcohol, the melting temperature of the organic phase-change material is 0-10 DEG C, the crystallization temperature is-5-5 DEG C, and the melting temperature and the crystallization temperature can be adjusted according to requirements. The material has high latent heat of phase change, and can be efficiently used in scenes of cold chain transportation, refrigeration house energy conservation and the like. The material is non-toxic and harmless, has stable cycle performance, and effectively overcomes the defects of poor cycle performance, easy phase separation, large supercooling degree and the like of an inorganic material. The material is applied to cold storage energy conservation or cold chain transportation, and the effects of energy conservation, environmental protection and electric charge saving can be achieved by utilizing the valley electricity energy storage principle.

In order to obtain an electret melt blown nonwoven fabric having flexibility and high tensile elongation without performing a special post-processing treatment or using a special additive, the electret melt blown nonwoven fabric comprising polyolefin-based resin fibers is provided, the electret melt blown nonwoven fabric having a crystallization temperature of 80° C. or higher and 130° C. or lower and a heat quantity ΔHm of 3.0 J / g or higher and 20.0 J / g or lower at the time of the first temperature rise in the cycle of DSC.

The invention relates to the technical field of formaldehyde copolymer production, and discloses a trioxymethylene static crystallization separation method which comprises the following steps: S1, cooling crystallization: the crystallization temperature is 25-30 DEG C, and the crystallization time is 3-4 hours; s2, discharging mother liquor; s3, sweating, wherein the sweating temperature is 50-55 DEG C, and the sweating time is 2-2.5 h; and S4, melting to obtain a high-purity product. According to the invention, the characteristic that the solubility of trioxymethylene is reduced along with temperature reduction is utilized, and separation and purification are realized through temperature gradient regulation and control. The content of trioxymethylene in the prepared finished product reaches 94-96% and is higher than that in the prior art by 90-92%, the formaldehyde content is only 0.1-0.2%, and the impurity content is lower.

The invention relates to the technical field of composite adsorption material preparation, and discloses a salt lake lithium extraction titanium system composite adsorption resin preparation technology, which comprises: placing a macroporous organic resin matrix loaded with a titanium lithium source and maintaining a solvent saturation state in a closed reaction kettle, and carrying out a reaction under an inert gas and initial pressure atmosphere, according to the preparation method disclosed by the invention, the problem that a traditional powdery ion sieve is easy to break and lose is solved by utilizing the anti-wear characteristic of an organic resin framework; and meanwhile, an in-situ composite interface realized by the process inhibits pulverization attenuation of active components in circulation, and ensures long service life and structural integrity of the material.

Disclosed in the present invention is a preparation method for an anisotropic Nd2Fe14B / α-Fe bulk nanocrystalline composite permanent magnet material. The preparation method comprises the following steps: preparing a master alloy; crushing the master alloy into bulks, and, by means of a melt rapid quenching method, preparing amorphous ribbons; grinding the amorphous ribbons to obtain amorphous powder; cold-pressing the powder into bulks; and placing the bulks into a stainless steel mold, and heating and then rolling same, the stainless steel mold being of a plate-shaped structure, and a chamber for accommodating the bulks being formed in the stainless steel mold along the thickness direction thereof. The present invention presses the NdFeB amorphous powder into bulks, embeds same in the stainless steel mold, and performs rolling at a temperature below a crystallization temperature, so as to achieve high-temperature amorphous material crystallization.

A method for preparing a polybutene-1 composition with an elevated crystallization temperature, comprising blending as components A) 99.5-99.9% by weight, relative to the total weight of A)+B), of a butene-1 homopolymer, said butene-1 polymer being brought into or maintained in the molten state during the blending step, with B) 0.1-0.5% by weight, relative to the total weight of A)+B), of one or more alkanoyl hydrazines of specific formulas, the polybutene-1 composition thus obtained having a crystallization temperature T satisfying the following relationship: c C has. [0010] JPEG2024542582000029.jpg4092 Here, T c A is the crystallization temperature of butene-1 polymer A).

This invention discloses a method for preparing crystalline aluminum phosphate from aluminum polishing waste liquid, comprising the following steps: Step S1. Adding water and alkali to the aluminum polishing waste liquid, adjusting the pH to 2-5, to obtain a mixed solution; Step S2. Taking the mixed solution obtained in Step S1, filtering, to obtain an amorphous precipitate; Step S3. Taking the precipitate from Step S2, washing, to obtain a washed precipitate; Step S4. Adding water to the washed precipitate from Step S3 and transferring it to a hydrothermal reactor for crystallization, to obtain crude aluminum phosphate; Step S5. Taking the crude aluminum phosphate from Step S4, filtering, washing, and drying, to obtain crystalline aluminum phosphate; wherein, in Step S4, the crystallization temperature is 160-210℃, and the crystallization time is not less than 3 hours. This method is simple, easy to operate, and the reaction conditions are easy to control. It not only solves the environmental problems encountered in the chemical polishing process of aluminum materials, but also improves the industrial value of aluminum polishing waste liquid.

The present invention discloses a transition metal sulfide-doped single-element phase change memory material and a preparation method thereof, wherein the material is a MoS2-doped Sb thin film material, and the chemical structure of the thin film material is Sb x (MoS2) 100‑x , where 65at.%≤x≤85at.%, is obtained by dual-target sputtering of Sb single-element target and sulfur compound MoS2 target in a magnetron sputtering coating system. The advantage is that compared with GST phase change material, this phase change memory material has a higher crystallization temperature and a lower melting temperature, higher crystallization activation energy and ten-year data retention temperature, and greatly reduced resistance drift. In addition, the performance of single-element phase change Sb is successfully improved by doping with sulfur compounds, supporting the storage stability and reliability of phase change memory devices under long periods and high cycle numbers.

The invention discloses a treatment technology for separating a sorbic acid isomerization product, and belongs to the field of chemical engineering. According to the method, water and ethanol in the eliminated mother liquor are separated through selective separation of the dehydration membrane, so that an ethanol solution with higher concentration is obtained, the concentrations of sorbic acid and isomers in the solution are increased, then the crystallization temperature is controlled by utilizing the solubility difference of the sorbic acid and the isomers in the alcohol, and the crystallization efficiency is improved. Sorbic acid containing a low isomerization product is separated and recovered, so that the quality of a finished product is effectively improved.

The application discloses a kind of preparation of thin-layer Ti-MWW titanium silicalite and its application in epoxidation reaction, belong to inorganic chemical synthesis technical field.The application adds polycyclic aliphatic amine in the synthesis process of Ti-MWW molecular sieve, and reduces the crystallization temperature in the early stage of molecular sieve crystallization to delay the growth rate of molecular sieve C axis, obtain shorter C axis thin-layer Ti-MWW, greatly improve the diffusion performance of Ti-MWW molecular sieve by this method, increase the diffusion rate of reactant molecules in channel, so that the catalytic performance of molecular sieve is greatly improved, suitable for catalyzing propylene, butylene, hexene, cyclohexene, octene liquid phase epoxidation and the like.

The application provides a method for preparing calcium sulfate hemihydrate whiskers by using a low water activity system, and belongs to the technical field of calcium sulfate hemihydrate whiskers. The method comprises the following steps: aging, washing and drying treatment are performed on phosphogypsum raw materials to obtain modified phosphogypsum; inorganic salt, alcohol for reducing water activity and deionized water are mixed to obtain a mixed solution; the mixed solution is heated to a crystallization temperature, and then the modified phosphogypsum and a polyhydroxy alcohol crystallization regulator are added to perform a crystallization reaction; after the crystallization reaction is completed, solid-liquid separation, washing and drying are performed to obtain calcium sulfate hemihydrate whiskers. The method has simple process conditions and a controllable crystallization process, and can stably prepare calcium sulfate hemihydrate whiskers with a high length-diameter ratio.

The invention belongs to the technical field of steel and iron smelting and material processing, and particularly discloses a peritectic steel casting blank surface longitudinal crack control method which specifically comprises the steps that firstly, the physical performance of casting powder is optimized, the crystallization temperature of the casting powder is controlled in a segmented mode according to the carbon content of peritectic steel, and the content of lithium oxide in the casting powder is controlled; secondly, adjusting the control precision of the crystallizer, controlling the opening degree shrinkage amount of a wide-surface copper plate of the crystallizer, and adjusting the narrow-surface taper of the crystallizer according to the type of the crystallizer; and finally, technological operation optimization is conducted, and the position of a tundish submersed nozzle, the fluctuation range of the liquid level of a crystallizer and the frequency of increasing and decreasing the pulling speed are controlled. According to the technical scheme, longitudinal cracks on the surface of the peritectic steel casting blank can be effectively controlled, and the quality and the production efficiency of the casting blank are improved.

The application discloses a nucleating agent, a non-woven fabric and a preparation method and application thereof. The nucleating agent comprises inorganic nucleating agents and high molecular nucleating agents; the inorganic nucleating agents comprise at least one of carboxyl modified nano-silica, nano-calcium carbonate and sharp titanium type nano-titanium dioxide; the high molecular nucleating agents comprise at least one of a wholly aromatic polyester, ethylene-methacrylic acid copolymer sodium salt and a long chain carboxylic acid salt; and the nucleating agent is in the form of a water dispersion. The nucleating agent comprises inorganic nucleating agents and high molecular nucleating agents, and can quickly induce nucleation at a lower temperature, reduce crystallization enthalpy and significantly improve the crystallization rate, so that the mechanical properties, dimensional stability and thermal stability of the non-woven fabric are enhanced. The use of the nucleating agent makes the fiber structure of the non-woven fabric more uniform and dense, reduces the crystallization temperature, improves the mechanical properties, and reduces shrinkage and deformation during use.

Provided are a polyethylene having excellent processability and capable of reducing an injection molding defect rate, and a method of preparing the same. The polyethylene has an integral value in the region where the Log Mw is 5.5 or more in a GPC curve, wherein the x-axis is log Mw and the y-axis is dw / dlogMw, of 9% or less of the total integral value: and has a ratio (Tc10 / Tc40) of a crystallization temperature (Tc10) measured at a cooling rate of 10° C. / min to a crystallization temperature (Tc40) measured at a cooling rate of 40° C. / min of less than 1.04.

A dry fractionation process for high-solid-index grease comprises the following steps: a, raw oil at the temperature of T1 enters a pre-crystallization tank for pre-crystallization, and the pre-crystallization temperature is T2; b, filling the pre-crystallized raw oil in a membrane filter press, and cooling the raw oil in the membrane filter press after filling until the raw oil is cooled to a final temperature T3; c, starting an extrusion system of the membrane filter press to extrude the raw oil to obtain fractionation liquid oil and stearin, and purging a filter chamber after extrusion is finished; wherein the value range of T1 ranges from 40 DEG C to 50 DEG C, the value range of T2 ranges from 10 DEG C to 35 DEG C, and the value range of T3 ranges from 10 DEG C to 25 DEG C. The membrane type filter press can give consideration to extrusion and crystallization, pre-crystallized oil with a good flowing type is conveyed into the high-pressure membrane type filter press through a pump, pre-crystallized raw oil is subjected to program control cooling through cooling water, finally, the final temperature is reached, extrusion is conducted again, the automation degree is high, and the PKS yield is high.

The invention relates to a process for recycling a particulate semi-crystalline polyamide, the initial particulate semi-crystalline polyamide having already been used in a layer-by-layer printing process, the process comprising: - a step of contacting the initial particulate semi-crystalline polyamide with water and at least one acid; - a step of heating the initial particulate semi-crystalline polyamide to a temperature above Tc – 20°C and below Tf, Tc denoting the crystallization temperature of the initial particulate semi-crystalline polyamide and Tf being the melting temperature of the initial particulate semi-crystalline polyamide, and - a step of collecting the treated particulate semi-crystalline polyamide, in which the treated particulate semi-crystalline polyamide has an inherent viscosity lower than the inherent viscosity of the initial particulate semi-crystalline polyamide.

This invention discloses a method for removing BQB impurities from aripiprazole raw material. This method involves controlling the reaction solvent and post-reaction processing during aripiprazole synthesis. By rationally controlling the ratio of reaction solvent to water, the post-treatment temperature, the crystallization temperature, and the time, BQB impurities can be effectively removed. This invention features a simple process and high removal efficiency. Compared to existing technologies, this invention operates under milder conditions and requires less sophisticated equipment, making it suitable for industrial production.

The invention relates to an easy-to-disperse high-performance organic carboxylate nucleating agent and a synthesis method and application thereof, and the method comprises the following steps: adding an organic acid or an anhydride compound and an organic solvent into a container equipped with a stirrer and a reflux condenser according to a predetermined ratio, and stirring and mixing to form slurry; raising the temperature and stirring to prepare a precursor; adding the fatty acid metal salt into another organic solvent solution according to a preset ratio, and uniformly stirring to obtain a fatty acid metal salt suspension solution; dropwise adding the mixture into a container with a nucleating agent precursor, filtering a product after reaction, and drying and crushing the product; the nucleating agent is obtained. Fatty acid can form a coating surface layer, so that agglomeration of super particles of the nucleating agent is prevented, the dispersion effect of the nucleating agent is enhanced, a prepared plastic product shows a lower haze value and a higher crystallization temperature, the use convenience is improved, and the application field is widened.

A method for reducing or eliminating Si contained in an aluminum alloy including: holding the aluminum alloy and Sn at a melt temperature at which the aluminum alloy and Sn are melted; lowering the melt temperature, and holding the aluminum alloy and Sn at a Si crystallization temperature at which solid Si is crystallized while maintaining a molten state of Sn and Al, and separating the solid Si; and further lowering the temperature and holding the aluminum alloy and Sn at an Al crystallization temperature at which Al is crystallized and Sn is in the molten state, to separate and recover solid Al.

The application discloses a solid selenium diffusion process and application thereof in antimony-based solar cells. Advantages of the solid selenium diffusion process are as follows: 1) the evaporation temperature and annealing crystallization temperature of selenium are very low (about 200 DEG C), so that the temperature of the solid selenium diffusion process is much lower than that (about 350 DEG C) of a conventional selenization process based on selenium vapor; 2) a high-quality antimony selenide interface layer can be prepared by using the process, the interface band structure between an absorption layer and a back electrode can be optimized, and the carrier transport of the device can be improved; 3) the solid selenium diffusion process is highly compatible with a full-vacuum process of the antimony-based solar cell, and can realize full-process physical preparation, and is suitable for large-area industrial manufacturing; and 4) the full-inorganic photovoltaic device prepared by using the solid selenium diffusion process has the advantages of low material cost, environmental friendliness, high stability and the like, and the indoor photovoltaic efficiency of the prepared device is as high as 12.00%, and the device has a wide application prospect in the field of indoor photovoltaic.

The invention discloses a Y-type molecular sieve and a preparation method thereof, a catalyst and a preparation method thereof, and a Fischer-Tropsch wax hydrocracking method, and belongs to the technical field of chemical engineering. The method comprises the following steps: S1, mixing a first alkali source, a first aluminum source, a first silicon source, first water and a template agent to obtain a first mixed solution, and pre-crystallizing to obtain a seed crystal guiding agent; the pre-crystallization temperature is 15-35 DEG C, the pre-crystallization time is 24-60 hours, and the template agent is poly (diallyldimethylammonium chloride); s2, mixing a second alkali source, a second aluminum source, a second silicon source and second water to obtain mother liquor; mixing the guiding agent and the mother liquor to obtain initial gel; crystallizing the initial gel to obtain an alkali metal Y-type molecular sieve; and S3, mixing the alkali metal Y-type molecular sieve with an ammonium-containing solution, carrying out ammonium ion exchange treatment to obtain a first Y-type molecular sieve, and carrying out first roasting treatment to obtain a second Y-type molecular sieve. The particle size of the molecular sieve is smaller than 520 nm, and the silica-alumina ratio is larger than 6.5.

The application discloses a kind of dry treatment desulfurization wastewater system and process flow, high-temperature hot flue gas of boiler induced draft fan outlet is used, dust removal is entered into evaporator coil heat exchange to realize brine concentration, and cooperate with damper to realize temperature rise in evaporator and reach crystallization temperature requirement, by concentrated liquid direct injection high-temperature air duct to carry out vapor-solid separation, then into dryer to carry out gas-solid high-temperature cyclone separation.The application is more reasonable in arrangement, has lower maintenance cost, has wider applicability in finished product production, has higher economic benefit, especially avoids chloride crystalline salt pollution ash, so that ash and chloride crystalline salt can be collected and utilized separately.

The application provides a purification method and dichloroisocyanurate obtained by using the method. The purification method of dichloroisocyanurate comprises the following steps: repeatedly crystallizing crude dichloroisocyanurate obtained in a production synthesis process to obtain purified dichloroisocyanurate. The purification method of dichloroisocyanurate of the application utilizes the different melting points of dichloroisocyanurate and other impurities, and is designed to be repeatedly crystallized at different gradient temperatures. By adjusting the crystallization temperature and the crystallization time, the impurities in the dichloroisocyanurate can be removed. Compared with the crude distillation method, the obtained dichloroisocyanurate has higher purity, and is safer and easier to operate.

The invention discloses a quaternized thiophene polymer and a preparation method thereof.The structural formula of the quaternized thiophene polymer is shown in the specification, the quaternized thiophene polymer structurally contains a C6 alkyl chain and a quaternary ammonium salt long chain containing a polar group, the polymer can be endowed with good alcohol solubility, then the environment-friendly solvent processing characteristic can be achieved, and meanwhile, the quaternized thiophene polymer can be used for preparing a solvent. And the crystallization temperature and the melting point of the polymer can be reduced, so that the melting processing characteristic at lower temperature can be realized.

A method for producing a porous ceramic structure, comprising the following: a) Making kneaded clay by kneading a raw material; b) Obtaining a pressed body by shaping the kneaded clay and c) Firing of the pressed body, wherein the raw material contains the following: Cordierite; Cer and iron and / or manganese and / or cobalt, wherein the process c) forms a porous ceramic structure comprising a porous structural body formed essentially of cordierite, cerium-containing particles firmly attached to the structural body, and metal oxide particles each firmly attached to an inside of a pore in the structural body, wherein the metal oxide particles are particles of an oxide having a spinel structure containing iron and / or manganese and / or cobalt, The process c) includes the following: c1) Raising the temperature of the pressed body to a first temperature that is less than or equal to a liquid phase formation temperature; c2) Increasing the temperature of the pressed body from the first temperature to a second temperature that is higher than the liquid phase formation temperature and lower than a crystallization temperature of the metal oxide particles; c3) Increasing the temperature of the pressed body from the second temperature to a third temperature which is greater than the crystallization temperature and less than or equal to a maximum temperature; and c4) Maintaining the temperature of the press body at the maximum temperature for a specified period of time, and wherein a rate of temperature increase in process c2) in the range of 100 °C / h to 200 °C / h.

A method for improving a recovery rate of recycled bis(2-hydroxyethyl) terephthalate (BHET) is provided, which includes: providing a recycled polyester fabric; using a chemical de-polymerization liquid to chemically depolymerize the recycled polyester fabric, so as to form a de-polymerization product containing BHET; dissolving the BHET in water to form a aqueous phase liquid; cooling the aqueous phase liquid from a dissolution temperature to a first crystallization temperature, so as to crystallize at least a part of the BHET; and cooling the aqueous phase liquid from the first crystallization temperature to a second crystallization temperature, so as to crystallize at least another part of the BHET.

The invention relates to a fiber-reinforced tape comprising a thermoplastic composition comprising a propylene-based polymer and a plurality of continuous glass fibers dispersed in the thermoplastic composition, wherein each of the plurality of continuous glass fibers extends in the longitudinal direction of the tape, wherein the thermoplastic composition has a crystallization temperature determined by differential scanning calorimetry according to ISO 11357-3 using a heating rate of 10˚C / min and a cooling rate of 10˚C / min of at least 122.0 ⁰C.

A method for increasing the BEMT content in a composition comprising 2,4-bis[4-(2-ethylhexyloxy)-2-hydroxyphenol]-6-(4-methoxyphenol)-1,3,5-triazine (BEMT), the method comprising the steps of: a) providing a composition comprising BEMT and impurities; b) dissolving the composition in a solvent mixture at a first dissolution temperature to produce an unsaturated BEMT solution, wherein the solvent mixture comprises at least one polar solvent; c) lowering the temperature of the unsaturated BEMT solution to a saturation temperature, wherein the saturation temperature is below the first dissolution temperature, to produce a saturated BEMT solution; d) further lowering the temperature of the first saturated BEMT solution to a first crystallization temperature, wherein the first crystallization temperature is below the saturation temperature, thereby producing a supersaturated BEMT solution; e) during step d), adding BEMT seed crystals in an amount ranging from 0.00001 wt.-% to 20 wt.-% relative to the total weight of the composition to the supersaturated BEMT solution to produce a first BEMT suspension comprising BEMT particles; f) a) Heating the first BEMT suspension to a second dissolution temperature to produce a second BEMT suspension containing fewer BEMT particles than the first BEMT suspension, wherein the second dissolution temperature is higher than and lower than the first crystallization temperature; g) Cooling the second BEMT suspension to a second crystallization temperature to produce a final BEMT suspension containing BEMT particles larger than those in the first BEMT suspension; h) Separating these BEMT particles from the final BEMT suspension, wherein the second crystallization temperature is lower than the first crystallization temperature.