9748 results about "Reaction conditions" patented technology

The invention relates to the technical field of automation, in particular to an automatic monitoring and optimizing system for a fine chemical production process, which comprises the following steps of: extracting time-frequency domain fusion characteristic quantity of stirring torque power time sequence fluctuation data in real time through an incidence matrix construction module, dynamically inverting a thixotropic index by combining a deep neural network model, and optimizing the stirring torque power time sequence fluctuation data; the problem that a traditional method is difficult to perceive material rheological characteristics in real time is solved. The dynamic coupling analysis module analyzes the material viscosity change rate based on the thixotropic index, fuzzy PID control is adopted to generate a stirring speed adjusting instruction dynamically matched with the viscosity and a jacket temperature compensation value, and the defects of uneven mixing and local overheating caused by lagging adjustment of process parameters are overcome; the multi-target collaborative optimization module locks the mass optimization weight in the viscosity sudden change stage, rapidly stabilizes the reaction condition through a feed-forward compensation algorithm, dynamically balances the stirring power consumption and the heat transfer efficiency based on Pareto frontier search in the steady state stage, and solves the conflict between the mass and the energy efficiency target.

The application provides a process method for preparing (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl) phosphonic acid, and particularly relates to the technical field of organic synthesis. The process method is that, under alkaline conditions, a halogenated phosphonate compound is added into a 3,6-dimethoxy-9H-carbazole solution to perform a reaction, hydrochloric acid aqueous solution is added after the reaction to perform acidolysis degreasing, and finally (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl) phosphonic acid is obtained through extraction, reflux adsorption and beating purification. The process method uses 3,6-dimethoxy-9H-carbazole as a starting material, realizes the synthesis of the target product through one-pot reaction, has mild reaction conditions, uses non-toxic raw materials which are easy to obtain, has simple synthesis process, is convenient to operate, and has high separation yield.

The invention provides an iron-based phosphate positive electrode material as well as a preparation method and application thereof. The preparation method of the positive electrode material comprises the following steps: reacting a mixed material containing metallic iron and a phosphorus source at normal temperature to 100 DEG C to form a solid-liquid mixture containing a phosphate iron salt compound; mixing the solid-liquid mixture with an acidity regulator, a carbon source and a sodium source, and sanding to obtain slurry; performing drying treatment on the slurry to obtain a precursor material; and sintering the precursor material under a protective atmosphere condition to obtain the iron-based phosphate positive electrode material. According to the method provided by the invention, the metal iron and the phosphorus source do not need to be mixed and completely dissolved to form a solution in the reaction process, and anhydrous iron phosphate does not need to be formed firstly, so that the method for preparing the iron-based phosphate positive electrode material is short in process and relatively low in requirements on reaction conditions, and is applicable to industrial production and large-scale production.

A process for upgrading a plastic derived oil includes providing the plastic derived oil comprising hydrocarbons and greater than or equal to 100 ppmw halogen-containing compounds and contacting the plastic derived oil with an MMO catalyst in a first reactor at reaction conditions to remove halogens from the plastic derived oil to produce a first reactor effluent with less than 100 ppmw halogen-containing compounds. The process includes contacting the first reactor effluent with an adsorbent to produce a treated first reactor effluent, passing the treated first reactor effluent to a second reactor, and contacting the treated first reactor effluent with a cracking catalyst in the second reactor. Contacting with the cracking catalyst may cause hydrocarbons in the treated first reactor effluent to undergo catalytic cracking to produce a second reactor effluent comprising light olefins, naphtha range hydrocarbons, or combinations thereof.

The invention discloses a uniformly radial positive electrode material precursor and a preparation method thereof. The cross section of the uniformly radial positive electrode material precursor is uniformly radial, and the shape of the uniformly radial positive electrode material precursor is divided into a core and an outer layer, the core is loose and porous, and the outer layer is in a regular radial shape; the method adopts a coprecipitation method to carry out two-stage reaction preparation, in the first reaction stage, an inner core layer is prepared; a second reaction stage: preparing a shell layer to reach a target particle size; the secondary particle D50 is 6.0-14.0 microns, the TD is greater than 1.90 g / cm, and the BET is less than or equal to 14m < 2 > / g; the precursor is small in structure core and compact in outer layer, particles grow in a radial mode from inside to outside, lithium ions can be separated and embedded out easily, the particle structure is more stable, and excellent rate performance and cycling stability are shown; a staged coprecipitation method is adopted, and controllable growth of a particle structure is realized by accurately controlling the ratio of oxygen to nitrogen and reaction conditions; according to the whole process design, the complex parameter adjusting range is reduced, and the production stability and repeatability are improved.

The invention discloses a reaction condition optimization control method and system for biological aviation kerosene production, and particularly relates to the field of biological aviation kerosene production. The method comprises the following steps: firstly, acquiring parameters such as temperature, pressure, flow, catalyst activity and raw material components of biological aviation kerosene in real time through a sensor module consisting of a temperature sensor, a pressure sensor, a flow sensor and the like, and then carrying out pretreatment operations such as median filtering and wavelet denoising on acquired data; constructing an LSTM-Transformer hybrid model based on the preprocessed data to predict the second-by-second value of each parameter in the future 10 minutes, correcting the predicted value according to a catalyst activity index formula, further optimizing the prediction model by using a shadow model, comparing the predicted value with a preset interval and a threshold value, judging the state of the predicted value, and determining the second-by-second value of each parameter in the future 10 minutes. And finally, generating a fixed fine-tuning, strengthening or emergency control strategy according to a judgment result. According to the method, the biological aviation kerosene production reaction conditions can be accurately predicted, regulated and controlled, and the production stability, safety and product quality are improved.

The invention discloses a photocatalytic preparation method of a deuterated acetamide compound, and belongs to the technical field of synthesis of deuterated acetamide compounds. According to the technical scheme, the method is characterized in that a dichloroacetamide compound is used as a raw material, D2O is used as a deuterium source, and the dideuterated acetamide compound is synthesized through reaction under the room-temperature nitrogen illumination condition; according to the method, dichloroacetamide compounds are taken as raw materials, D2O is taken as a deuterium source, deuterated dichloroacetamide compounds are synthesized through room-temperature reaction, and monodeuterated or trideuterated acetamide compounds are respectively obtained through photocatalytic reaction according to different solvents (H2O or D2O) added into a system. The preparation method provided by the invention has the advantages of simple and safe operation, mild reaction conditions, no transition metal participation, cheap and easily available deuterium source, high deuteration rate, controllable number and the like.

The invention relates to the technical field of catalysts for gas purification, in particular to a hierarchical pore metal-based catalytic adsorbent as well as a preparation method and application thereof. The invention discloses an integrated preparation method combining a sol-gel method and a template method, which comprises the following steps of: adding a template agent before forming gel, adding a proper amount of ammonia water in an aging process, accurately controlling other reaction conditions and a raw material ratio, and controlling a spatial confinement effect of the template method and a chemical reaction in a sol-gel process to obtain a sol-gel composite material. The morphology and size of the catalytic adsorbent can be accurately regulated and controlled, the hierarchical pore metal-based catalytic adsorbent with a microporous structure as a main material and mesopores and macropores as coexistence is finally prepared, the hierarchical pore structure provides rich adsorption sites and catalytic activity centers, and the hierarchical pore metal-based catalytic adsorbent has high adsorption capacity, high selectivity, good catalytic activity, good stability and easy regeneration.

The invention belongs to the technical field of petrochemical process simulation and intelligent optimization control, and particularly relates to a method for constructing and optimizing a full-fraction oil catalytic cracking reaction kinetic model. The construction method comprises the steps of raw material matrix construction, reaction network construction, product property calculation, model parameter optimization and process prediction calculation. The optimization method comprises the following steps: constructing a process optimization index system comprehensively reflecting environmental and economic targets; systematic optimization of reaction conditions and product distribution is realized; intelligent regulation and efficient prediction of the catalytic cracking process are realized; and optimal reaction operation conditions meeting multiple requirements are obtained. The method is high in adaptability, process parameters can be adjusted according to the properties of the raw materials, and efficient conversion is achieved. By optimizing the catalytic cracking process, the yield of aromatic hydrocarbon can be remarkably improved. By predicting and optimizing reaction conditions through the kinetic model, the energy consumption is reduced, the reaction efficiency is improved, meanwhile, the equipment investment and operation cost can be reduced, and the production efficiency and economic benefits are improved.

The invention discloses an epoxy resin-based NTC (Negative Temperature Coefficient) composite material containing ionic liquid and carbon black as well as a preparation method and application of the epoxy resin-based NTC composite material. The preparation method of the material comprises the following steps: mixing the ionic liquid and the epoxy curing agent, heating on a heating table, stirring and mixing at the same time, then adding the epoxy resin, the carbon black, the surfactant and the solvent, mechanically stirring and uniformly mixing, and heating in a vacuum oven to remove the solvent to obtain the material. And then carrying out hot pressing for a certain time through a press vulcanizer at a certain temperature to obtain the epoxy resin-based NTC composite material containing the ionic liquid and the carbon black. The epoxy resin-based NTC composite material containing the ionic liquid and the carbon black has the advantages of high B value, good mechanical strength, high heat conductivity coefficient, high crosslinking density and the like, and the preparation method is simple to operate, mild in reaction condition, low in raw material cost and suitable for large-scale industrial production and application.

The invention belongs to the technical field of electrocatalyst material preparation, and discloses a long-range disordered localized CoOOH ultrathin nanosheet electrocatalyst as well as a preparation method and application thereof, fluorine-doped cobalt selenide nanobelts prepared by a low-temperature annealing method are used as a base material, and the CoOOH ultrathin nanosheet electrocatalyst is prepared by in-situ reconstruction under an alkaline electrolyzed water anode oxygen evolution reaction condition. In the preparation process of the CoOOH ultrathin nanosheet provided by the invention, lattice cobalt is stabilized in the water electrolysis anode reconstruction process through fluorine ions with strong bonding action with cobalt ions, so that the long-range disordered structure of amorphous CoOOH generated after reconstruction is limited by localization, and the alkaline water electrolysis anode reaction performance is improved. The catalyst has activity and durability obviously superior to those of a commercial ruthenium oxide catalyst in industrial application of anion exchange membrane water electrolysis hydrogen production.

The invention discloses a preparation method of a pyrazolone amino-acid ester derivative. The pyrazolone amino-acid ester derivative is obtained through three-component cascade reaction by taking pyrazolone imine, a pentafluorophenylacetate derivative and alcohol as reactants and chiral isothiourea as a catalyst. According to the invention, challenges of competitive side reactions between a plurality of reaction substrates and intermediates and stereoselectivity control are overcome, the application range of the substrate combination of the existing system is broken through, and synthesis of a series of pyrazolone amino-acid ester derivatives is realized in a green and efficient manner. According to the method disclosed by the invention, substrate preassembly is not needed, transition metal catalysis is not needed, raw materials and the catalyst are cheap and easy to obtain, reaction conditions are mild, and the substrate application range is wide. In addition, the invention also provides a new way for introducing the medicine bioactive molecules into the synthesis of the pyrazolone amino-acid ester compound.

The invention discloses a method for degrading dioxin in fly ash and stabilizing heavy metals, which comprises the following steps: carrying out water washing treatment on the fly ash, and carrying out solid-liquid separation to obtain water washing slag; mixing the washed slag with water, adding zero-valent iron and sulfite, carrying out hydrothermal treatment, and carrying out solid-liquid separation to obtain hydrothermal slag and hydrothermal liquid; according to the method for degradation of dioxin in fly ash and stabilization of heavy metal in cooperation with degradation of dioxin in fly ash, under the combined action of zero-valent iron, chlorite and a hydrothermal environment, efficient degradation of dioxin in fly ash can be rapidly achieved under the lower reaction condition, stabilization of heavy metal in fly ash can be synchronously achieved, and the method is suitable for industrial production. The method has the advantages of being low in cost, mild in reaction condition, high in treatment efficiency, good in treatment effect, environmentally friendly and the like, can effectively solve the problems existing in the prior art, provides powerful support for harmless treatment and resource utilization of the waste incineration fly ash, and has wide engineering application prospects.

The invention discloses a non-specific peroxygenase mutant and application thereof and a preparation method of 25-hydroxyvitamin D3, and particularly relates to a protein obtained by taking an amino acid sequence as shown in SEQ ID NO.1 as a starting sequence and mutating amino acid residues as shown in the 20th site and / or the 25th site and / or the 57th site. The catalyst has relatively high catalytic activity and stereocatalysis specific selectivity; according to the method, acetone, vitamin D3, hydrogen peroxide and a non-specific peroxygenase mutant are respectively added into a potassium phosphate buffer solution with the pH value of 7.0-8.0 to form a reaction mixed solution, an oxidation reaction is carried out for 10-50 hours at the temperature of 25-35 DEG C, the 25-hydroxyvitamin D3 is generated, the reaction condition is mild, the reaction operation is simple and convenient, the conversion rate is high, the cost is low, the preparation efficiency of the 25-hydroxyvitamin D3 is greatly improved, and the method is suitable for industrial production. Good industrial application prospects are realized.

The invention belongs to the field of enzymatic preparation of structural phospholipids, and particularly relates to a method for preparing phosphatidylserine through interfacial enzyme catalysis. A series of high-activity immobilized phospholipase are prepared by innovatively adopting bifunctional group modified hollow mesoporous silica microspheres as a carrier and adsorbing immobilized phospholipase D. The catalyst has the functions of a catalyst and an emulsifier, and a Pickering emulsion interfacial enzyme catalysis system can be efficiently constructed. In the system, the phosphatidylcholine and the serine are efficiently converted into the phosphatidylserine through a phosphatidyl transfer reaction, the conversion rate of the phosphatidylserine within 20 minutes can reach 85%-95%, and the catalytic efficiency reaches up to 372 mmol / (g.h). In addition, after the catalyst is recycled for 10 times, the conversion rate is still kept at 70.9%, and the catalyst shows excellent stability and reusability. The method has the remarkable advantages of being mild in reaction condition, high in catalytic efficiency, capable of being repeatedly used and the like, and a new technical approach is provided for industrial production of phosphatidylserine.

The invention discloses a modified amine curing agent and a preparation method thereof, and an epoxy resin composite material and a preparation method thereof, and belongs to the field of resin and composite materials. According to the curing agent, a C2-C8 alkyl chain is grafted to a methylene site of 4, 4 '-diaminodiphenylmethane (MDA) through free radical substitution and alkylation reaction, and a molecular structure with a flexible alkyl chain and a rigid benzene ring is formed. The preparation method comprises the following two steps: generating a halogenated intermediate from MDA and a halogen simple substance under certain reaction conditions, alkylating the halogenated intermediate with a Grignard reagent (RMgX), and purifying. The curing agent and epoxy resin are compounded, heated and cured, so that the epoxy resin composite material has relatively high impact strength and fracture toughness, has good tensile strength and hardness, has double functions of reinforcing and toughening, and solves the problem that reinforcing and toughening of traditional epoxy resin are difficult to be compatible; the method is suitable for the fields of aerospace, composite material adhesives and the like with harsh requirements on mechanical properties.

The invention relates to an MOF confinement ruthenium cluster catalyst for methanation of carbon dioxide as well as a preparation method and application of the MOF confinement ruthenium cluster catalyst. The catalyst comprises a carrier and an active component loaded on the carrier, the carrier comprises a metal organic framework containing hydroxyl; the metal organic framework comprises UiO-66 (UiO-66); the active component comprises metal ruthenium; the active component grows in a pore channel of the carrier and forms a metal cluster. The catalyst provided by the invention realizes 100% methane selectivity and 98.4% carbon dioxide (CO2) conversion rate under the conditions of 1 MPa and 220 DEG C, is almost close to thermodynamic limit equilibrium conversion rate (99.4%) and is superior to the currently reported Ru-based CO2 methanation catalyst, and the catalyst shows good catalytic activity and structural stability in the process of continuous reaction for 650 hours. The catalyst provided by the invention has the characteristics of simple preparation method, high metal dispersibility, mild reaction conditions, high conversion rate, good selectivity, excellent stability and the like.

The invention discloses a large-scale preparation method of lithium sulfide, and belongs to the technical field of preparation of battery materials. Lithium sulfate monohydrate is adopted as a reaction raw material and is subjected to dehydration and purification treatment to obtain anhydrous lithium sulfate, and the anhydrous lithium sulfate is calcined in hydrogen and carbon dioxide mixed gas without introducing other impurities; the method has the advantages that safety under high-temperature calcination reaction can be guaranteed, the produced lithium sulfide crude product is dissolved by the methanol / isopropanol mixed solution to directly generate lithium sulfide crystals, redundant impurities can be removed by calcining the generated lithium sulfide crystals, no other by-products are generated in the reaction process, and the purity of lithium sulfide is guaranteed. According to the Li2S preparation method developed by increasing the purification step and exploring the reaction conditions and the impurity removal mode, low-cost, high-purity and large-scale preparation of Li2S can be realized.

The invention discloses an acetonitrile hydrogenation catalyst and a preparation method and application thereof. The acetonitrile hydrogenation catalyst is a transition metal modified Pt supported catalyst. A transition metal precursor adopted in the transition metal improvement is an oxide containing transition metal elements; the transition metal element is selected from at least one of titanium, vanadium, manganese, iron, cobalt, nickel and copper; the acetonitrile hydrogenation catalyst also comprises a carrier; the carrier is selected from at least one of gamma-Al2O3, SiO2, an MOR molecular sieve and a ZSM-5 molecular sieve. The catalyst can effectively catalyze acetonitrile hydrogenation to prepare ethylamine under mild reaction conditions. The supported catalyst provided by the invention has excellent reaction performance such as high acetonitrile conversion rate in acetonitrile hydrogenation reaction, the reaction condition is mild, the operation is simple, and the catalyst is easy to prepare and can be recycled.

The flexible ammonia synthesis process comprises the following steps: raw material gas is preheated and heated, then enters a temperature-controlled ammonia synthesis tower and reacts under the action of a catalyst, the reacted gas is subjected to heat energy recovery through an outlet waste heat boiler and then enters an ammonia separation tank after being subjected to multi-stage cooling, and a liquid ammonia product is obtained at the bottom; the top non-condensable gas is pressurized by a circulating compressor and then returns to an inlet of the temperature control ammonia synthesis tower; in the temperature-controlled ammonia synthesis tower, raw material gas enters the tower through a raw material gas inlet and sequentially penetrates through the distribution plate, the catalyst bed I section, the distribution plate and the catalyst bed I section from outside to inside in the radial direction, reaction is carried out while heat exchange is carried out, and reaction gas is led out from a reaction gas outlet in the bottom after being converged in the center. The method is simple in process, easy to control, low in equipment investment and operation cost, energy-saving, consumption-reducing, high in reaction efficiency and loose in reaction condition, temperature runaway or temperature loss of a bed layer is not easily caused under high load, and stable operation of the system can still be kept under 0-120% fluctuation of feed gas flow.

The invention discloses preparation of a high-uniformity cerium oxide abrasive material and application of the high-uniformity cerium oxide abrasive material in a chemical mechanical polishing solution. According to a method, cerium nitrate or cerium oxalate is used as a cerium source, a cationic or nonionic surfactant is used as a structure-directing agent, and the high-uniformity cerium oxide abrasive material is prepared in a mixed solvent system formed by water and isopropanol or water and diethylene glycol according to a specific volume ratio. The preparation method comprises the following steps: regulating the particle size and the morphology structure through a solvothermal reaction, carrying out cleaning, drying and high-temperature calcination treatment on a reaction product to obtain sphere-like cerium oxide nano-particles with high particle size concentration ratio, moderate surface roughness and good dispersity, adding cerium oxide powder into deionized water, and carrying out ultrasonic dispersion to obtain the spherical cerium oxide nano-particles. And sequentially adding a dispersing agent and amino acid while stirring, uniformly stirring, fixing the volume, and adding a pH regulator to enable the solution to be weakly acidic, thereby obtaining the chemical mechanical polishing solution. The cerium oxide submicron powder which is different in surface appearance, particle size and distribution uniformity is prepared by adjusting the solvent ratio and other reaction conditions.

The invention discloses preparation and application of an imido covalent organic framework material containing imidazolyl ionic liquid. The imido covalent organic framework material (ILs-TPN-COFs) containing the imidazolyl ionic liquid is obtained by connecting the imidazolyl ionic liquid [CnCmILs (at) Br] to an imido covalent organic framework TPN-COFs through a covalent bond. The material has an ionic liquid tertiary amine N active site and a halogen anion active site, and can promote CO2 activation and ring opening of epoxide. The ILs-TPN-COFs catalytic material has the advantages of uniform distribution of active sites, better stability, easiness in separation of the catalyst from a reaction system, better repeatability and the like. According to the invention, the prepared novel ILs-TPN-COFs material is applied to catalysis of synthesis of propylene carbonate from carbon dioxide and epoxypropane, and shows excellent catalytic performance under mild reaction conditions.

The invention discloses a method for preparing a multi-carbon product through acid electrocatalysis carbon dioxide reduction and belongs to the field of chemistry and chemical engineering. An electro-catalysis carbon dioxide reduction system takes a Cu-based catalyst modified by HEDP as an electrode material, and K < + > in an electrolyte can be effectively enriched on the surface of the Cu-based catalyst due to the complexing effect of HEDP on K < + >, so that the local pH is increased, C-C coupling is promoted, and efficient conversion of CO2 to a multi-carbon product under an acidic condition is realized. According to the invention, HEDP molecules with a K < + > complexing function are introduced into the surface of a Cu-based catalyst for the first time, and the Cu-based catalyst is applied to an acidic electrocatalytic carbon dioxide reduction system with low K < + > concentration. The preparation method of the electrocatalytic system cathode catalyst is simple, mild in reaction condition and simple to operate, can effectively relieve the problem of carbonate deposition in an alkaline electrocatalytic system, and has industrial application prospects.

The invention relates to a method and a system for synthesizing N-methylaniline and co-producing N, N-dimethylaniline by a gas phase method, and belongs to the technical field of chemical engineering. The system comprises a raw material gasification unit, a reaction unit, a separation and rectification unit and a hydrogen recovery unit which are connected through pipelines. The method comprises the following steps of: firstly, mainly synthesizing N-methylaniline from raw materials aniline and part of methanol in a first-methylaniline reactor, then partially or completely feeding first-methylaniline reaction gas into a second-methylaniline reactor, adding methanol steam, and further reacting to generate N, N-dimethylaniline. And after the product gas is subjected to heat exchange energy recovery, a liquid phase and a gas phase respectively enter the separation and rectification unit and the hydrogen recovery unit. The purification of N-methylaniline and N, N-dimethylaniline and the recovery of byproduct hydrogen are realized. The yield of N, N-dimethylaniline (in terms of aniline) can be adjusted in a range of 5-30% by adjusting reaction conditions and a feeding ratio.

The invention belongs to the technical field of hydrogen production, and particularly relates to an electric heating catalyst and an electric heating catalytic ammonia decomposition hydrogen production system. The electrothermal catalyst comprises a catalyst component and a foam alloy electrode, wherein the catalyst component comprises an active metal, a carrier metal oxide and an auxiliary metal oxide; the interior of the foam alloy electrode is of a porous network structure, the catalyst components are uniformly distributed on the outer surface of the foam alloy electrode and the inner wall of the porous network structure, and the thickness of the catalyst components distributed on the outer surface of the foam alloy electrode and the thickness of the inner wall of the porous network structure are both 5-10 microns. The foam alloy electrode is used as a heating unit and a carrier for catalyst growth, catalyst forming is not needed, good heat transfer and mass transfer efficiency is achieved, meanwhile, the electro-thermal catalytic bed design of multiple sections of bed layers is combined, temperature subsection control of the multiple sections of bed layers is achieved, the optimal reaction conditions can be kept at different reaction stages, and the reaction efficiency is improved. Therefore, the reaction efficiency is obviously improved.

The invention relates to the technical field of methane cracking and hydrogen production, and discloses a metal-modified Co-Bi liquid alloy catalyst, wherein the catalyst uses Co as an active component, uses Bi low melting point metal as a solvent, and uses a third metal M as an auxiliary agent; the invention also discloses a method for preparing the catalyst, comprising: calcining a cobalt salt to generate cobalt oxide, and then forming CoO-MO X The mixture powder was finally heated under N2 and H2 atmosphere to obtain CoO‑MO X The powder is mixed with elemental Bi to obtain a cobalt-bismuth ternary liquid alloy catalyst; the present invention also discloses a method for applying the catalyst to methane cracking and hydrogen production, comprising: heating the preheating furnace to a certain temperature, introducing pure methane gas, and reacting under normal pressure, at a temperature of 500 to 700°C, with a methane space velocity of 1 to 100 mL / g·min, and after the reaction is completed, the temperature drops to room temperature in an N2 atmosphere, and the carbon product is taken out of the reaction tube after cooling. The catalyst disclosed by the present invention has the advantages of high activity, good stability, strong methane cracking ability, mild reaction conditions, simple preparation process, and long life.

The invention relates to the technical field of quantum computing and molecular electronic devices, in particular to a probabilistic bit device based on polyfluoroaryl methyl free radicals and a preparation method of the probabilistic bit device. According to the probabilistic bit device, the coupling efficiency of molecules and electrodes is improved by virtue of the characteristic that the paramagnetic unpaired electron spin state of tri (polyfluoroaryl) methyl free radical molecules can be used as a random expansion physical entropy source and high electronegativity and stability formed by modification of a plurality of strong electron-withdrawing fluorine atoms in the molecules. During the operation period of the device, the spin fluctuation can efficiently regulate and control tunneling current passing through molecules, promote random conversion between output high and low current states, show excellent random binary fluctuation characteristics, and simultaneously have high sensitivity and long coherence time. Compared with the prior art, the device has remarkable advantages in the aspects of device stability, energy efficiency ratio and external field controllability. The preparation method is simple and convenient to operate, mild in reaction condition and beneficial to large-scale production.

The invention discloses a method for synthesizing methylal through acetalation by using a strongly acidic composite metal oxide, and particularly relates to preparation of a strongly acidic composite metal oxide catalyst and a method for preparing methylal through condensation of methanol and formaldehyde by using the strongly acidic composite metal oxide catalyst. The preparation method comprises the following steps: preparing a ZrO2-SiO2 composite oxide precursor by adopting a coprecipitation method, dipping and loading active metal and an auxiliary agent on the composite oxide precursor, and applying the active metal and the auxiliary agent to a process of preparing methylal through acetalation. The method has the advantages of simple synthesis, no corrosion to equipment, mild reaction conditions, capability of improving the activity and stability of the catalyst, and the like.

The invention provides a preparation method of 3-boron-L-phenylalanine or a derivative of 3-boron-L-phenylalanine. The preparation method provided by the invention comprises the step of preparing 3-boron-L-phenylalanine as shown in a formula (VI) or a derivative thereof by taking a compound as shown in a formula (III) as a raw material. The method has the advantages of mild reaction conditions, short route, high yield, few byproducts and low cost, and does not need an extremely low temperature condition process or complicated purification steps. # imgabs0 #