246results about How to "Optimizing the Reaction Temperature" patented technology

Methods for making cDNA molecules, for amplification of RNA by PCR and for preparation of cDNA libraries are provided. Kits for making cDNA molecules also are provided. Compositions are also provided comprising mixtures of reagents, including reverse transcriptases, buffers, cofactors and other components, suitable for immediate use in conversion of RNA into cDNA and RT PCR without dilution or addition of further components. These compositions are useful, alone or in the form of kits, for cDNA synthesis or nucleic acid amplification (e.g., by the Polymerase Chain Reaction) or for any procedure utilizing reverse transcriptases in a variety of research, medical, diagnostic, forensic and agricultural applications.

The invention discloses a modified phenol formaldehyde resin and a preparation method thereof, relating to the field of phenol formaldehyde resins. The preparation method comprises the following steps: reacting 100 parts of phenol, 10-200 parts of lignin and 1-20 parts of acidic catalyst at 80-200 DEG C for 2-8 hours to form a reaction liquid; regulating the temperature of the reaction liquid to 60-110 DEG C, adding 50-200 parts of formaldehyde and 2-20 parts of composite catalyst, and reacting for 1-5 hours to form a sticky matter; washing the sticky matter in 60-70 DEG C water 2-5 times, and dehydrating to obtain a lignin phenol formaldehyde resin; and pulverizing the lignin phenol formaldehyde resin to 200 meshes, and evenly mixing with 2-20 parts of powder nitrile-butadiene rubber to obtain the modified phenol formaldehyde resin. The free phenol content of the modified phenol formaldehyde resin is 2-5%, the thermal decomposition temperature is 400-490 DEG C, the toughness and strength are high, and the friction material prepared from the modified phenol formaldehyde resin has high adhesive property and frictional property.

The invention provides a method for preparing sulbenicillin disodium. The method comprises the following steps of: preparing alpha-sulfophenylacetyl chloride from alpha-sulfophenylacetic acid; reacting the alpha-sulfophenylacetyl chloride with 6-aminopenicillanic acid (APA) in the mixed solvents of water, ethanol and tetrahydro-2-methylfuran under the condition of the pH value of 5.6 to 7.0 and the temperature of 15 to 25 DEG C for 20 to 40 minutes to obtain crude sulbenicillin disodium; and obtaining the aqueous solution of the sulbenicillin disodium by post treatment and then cooling and drying the aqueous solution of the sulbenicillin disodium to obtain the final product, namely the sulbenicillin disodium. The method has the advantages of reducing energy consumption and saving production cost along with simple process, mild reaction condition and high yield.

The invention discloses a method for preparing small-particle-size cerium-activated yttrium aluminum garnet (YAG) florescent powder. According to the method, first, in fused salt, a wrapping structure of nanometer yttrium oxide (cerium oxide) @ aluminum oxide particles is obtained through controlled synthesis, then the aggregate of small-particle YAG florescent powder particles is generated through reaction in high-temperature fused salt, and finally the small-particle-size YAG: Ce florescent powder is obtained through weak ball milling. It is avoided that in the reaction process, the aluminum oxide particles and intermediate-phase particles abnormally grow, and while the high crystallinity of the particles is kept, final YAG is effectively controlled; the particle size of the Ce florescent powder has important significance for improving light-color quality of white-light LEDs, lowering the complexity of a white-light LED packaging technology and increasing the yield.

The invention discloses a low-energy-consumption preparation method for black phosphorus single crystals. The method comprises the following steps that rough black phosphorus powder is used as a phosphorus raw material and subjected to a heating reaction with metal simple substance tin and mineralizer stannic iodide under the vacuum condition, and through programmed cooling, the black phosphorus single crystals with larger size and higher purity are obtained. According to the method, required equipment is simple, the reaction temperature is low, the obtained black phosphorus single crystals are good in crystal form, the energy consumption can be obviously lowered, and the method helps to achieve industrial large-scale preparation of the black phosphorus single crystals.

The invention discloses a synthetic method of 1,1,1,3,3-perfluoropropane (HFC-245fa). The method comprises the following step of: preparing the HFC-245fa by carrying out two-step vapor phase catalytic fluorination reaction to 1,1,1,3,3-pentachloropropane (HCC-240) and anhydrous hydrogen fluoride under the action of a chromium-based catalyst, wherein the product containing HCFC-1233zd and HFC-1234ze is acquired through a first-step reaction, then the product acquired through the first-step reaction is directly led to react in a second reactor so as to acquire a product containing HFC-245fa, and then the target product HFC-245fa is acquired after impurities are separated. The synthetic method of the 1,1,1,3,3-perfluoropropane (HFC-245fa) has the advantages of simple process, low energy consumption and low equipment investment.

The invention discloses a method for co-production of 2,3,3,3-tetrafluoropropene and 1,3,3,3-tetrafluoropropene. The method includes the following steps: the raw materials, namely hexafluoropropene and hydrogen, enter a first reactor after preheating, wherein the first reactor is divided into three sections A, B and C, and the three sections are filled with different catalysts; different reaction conditions are controlled for the reaction, so that a mixture of 1,1,1,2,3-pentafluoropropane, 1,1,1,2,3,3-hexafluoropropane and hydrogen fluoride is obtained; after separation, 1,1,1,2,3,3-hexafluoropropane returns to the lower part of the section A of the reactor, 1,1,1,2,3-pentafluoropropane and a small amount of hydrogen fluoride enter a second reactor and react under the action of a catalyst, so that a mixture of 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene, hydrogen fluoride and unreacted 1,1,1,2,3-pentafluoropropane is obtained; the products are washed with water and then with alkali, dried, and distilled to obtain 2,3,3,3-tetrafluoropropene and 1,3,3,3-tetrafluoropropene products. The method provided by the invention is simple in process, small in investment, low in energy consumption and high in conversion rate.

The invention belongs to the technical field of supercapacitor electrode materials, and discloses a nickel sulfide nanosheet / carbon quantum dot composite material and a preparation method and application thereof. The composite material is prepared by the following steps: ultrasonically dispersing carbon quantum dots in an aqueous solution; adding soluble nickel salt and hexamethylenetetramine to obtain a carbon quantum dot / nickel hydroxide mixture precursor solution, enabling the precursor solution to grow on the surface of the foamed nickel at the temperature of 90-120 DEG C, mixing the carbon quantum dot / nickel hydroxide mixture with the sodium sulfide solution, performing hydrothermal reaction at the temperature of 100-140 DEG C, washing with water, and drying to obtain the composite material. The preparation method has the characteristics of simple preparation process, stable process, easiness in operation, low cost, no pollution and the like. The nickel sulfide nanosheet / carbon quantum dot composite material has a unique honeycomb nanosheet structure, which is beneficial to effective infiltration of an electrolyte, can enable the electrolyte to be in full contact with active substances, improves the electrochemical performance of the material, and can be used as a supercapacitor electrode material.

The invention discloses a difunctional self-healing polymer electrolyte. The difunctional self-healing polymer electrolyte comprises polyethylene glycol with double bonds, a cross-linking agent with adisulfide bond, an initiator and a chain transfer reagent, wherein the cross-linking agent with the disulfide bond has the disulfide bond and the hydrogen bond at the same time. The invention also provides a preparation method of the difunctional self-healing polymer electrolyte. The method comprises the following steps: S1, reacting a monomer with double bonds with a monomer with disulfide bondsin a first solution to obtain the cross-linking agent with the disulfide bond; S2, dissolving the cross-linking agent with the disulfide bond and polyethylene glycol with the double bonds in a secondsolvent, adding an initiator and a chain transfer reagent, performing deoxidizing, and heating for reaction to obtain a PEG-SS copolymer; and S3, dissolving the PEG-SS copolymer in a third solvent, adding a lithium salt for uniformly stirring, pouring the mixed solution into a film, and drying the film to obtain the difunctional self-healing polymer electrolyte. The cross-linking agent with the disulfide bond has the disulfide bond and the hydrogen bond at the same time, and self-healing of the electrolyte material at the room temperature is achieved.

The invention discloses an airlift sonochemical reactor, which is characterized in that: a vertical reacting cylinder is arranged; an ozone distributor with a gas outlet being upwards is arranged on the bottom of the reacting cylinder, a water outlet of a waste liquid tubing guide is close to the upper of the distributor, and keeps flow direction of water outlet being symmetrical with flow direction of ozone; energy transducers are arranged on the internal side wall of the reacting cylinder in an array manner, and a low frequency energy transducer and a high frequency energy transducer in a same horizontal plane are oppositely arranged on a same diameter line to form a energy transducer pair; and the number of the energy transducer pairs on a same horizontal plane is odd number, and the energy transducers uniformly distributed on a same circumference are arranged in an interval arrange manner of a low frequency energy transducer and a high frequency energy transducer. The airlift sonochemical reactor of the invention can high-efficiency utilize the synergism of ultrasonic wave and ozone, promotes acoustic cavitation effect, and can be used for treating industrial wastewater which is difficult to degrade.

The invention provides a microwave hydrothermal synthesizing method for carbon nanotube / LiFePO4 lithium ion battery anode material. The method comprises the following steps of respectively adding LiOH*H2O or Li2CO3 and NH4H2PO4 and FeC2O4*2H2O in deionized water, obtaining solution A; adding citric acid into the solution A, obtaining solution B; dispersing carbon nanotube (CNT) in concentrated HNO3 for soaking, and ultrasonic washing the CNT, obtaining purified CNT; adding the purified CNT in the solution B, obtaining reaction liquid; pouring the reaction liquid in a microwave hydrothermal kettle, sealing the microwave hydrothermal kettle, placing the sealed microwave hydrothermal kettle in a temperature and pressure doubly-controlled microwave hydrothermal reaction instrument for reacting, after the reaction is finished, naturally cooling the reactant to a room temperature, performing centrifugal separation for the reactant, washing the reactant by deionized water and absolute ethyl alcohol respectively, and then drying the reactant in a vacuum drying box, obtaining the carbon nanotube / LiFePO4 lithium ion battery anode material. According to the method provided by the invention, the microwave method and hydrothermal method are combined, so that the preparation of LiFePO4 lithium ion compound battery power body can be finished in the liquid phase at one step, the operation is simple, subsequent annealing heat treatment is not required, the reaction temperature is low, the reaction period is short, and the energy consumption is small, and moreover, the preparation cost of apower body can be reduced.