399 results about "Sodium hydride" patented technology

The invention discloses a preparation method of high-purity diiodosilane, which comprises the following steps: firstly, preparing a p-phenylsilane solution from phenyl trichlorosilane and sodium hydride as raw materials, rectifying and purifying the p-phenylsilane solution, directly reacting the p-phenylsilane solution with iodine to generate diiodosilane, and reacting phenylsilane with iodine to directly generate diiodosilane; in the process of preparing diiodosilane from phenylsilane, conditions are mild, the reaction process is controllable, the reaction time is shortened by controlling the temperature in the synthesis process and increasing the pressure of a reaction system, hydrogen iodide overflow is reduced, sodium hydride is adopted as a reducing agent in the reaction process, and the yield of diiodosilane is increased. The solid waste can be recycled, the cost can be effectively reduced, and industrialization of diiodosilane is facilitated.

The invention provides a GelMA microneedle patch loaded with chromogenic gold nano bipyramids and a preparation method thereof.The method comprises the steps that citric acid, chloroauric acid and a CTAC solution are mixed, then sodium borohydride is added, and a seed solution is obtained through stirring and standing; mixing chloroauric acid, silver nitrate, hydrochloric acid and CTAB (cetyltrimethyl ammonium bromide), and sequentially adding ascorbic acid and the seed solution to obtain a growth solution; carrying out centrifugation, morphology regulation and chemical etching purification to obtain a chromogenic gold nano bipyramid solution; the preparation method comprises the following steps: reacting gelatin with methacrylic anhydride in PBS, dialyzing and freeze-drying to obtain GelMA; dissolving GelMA in the gold nanoparticle bipyramid solution, and adding a photoinitiator LAP to obtain a mixed precursor solution; and the GelMA microneedle patch loaded with the gold nano bipyramid is prepared through mold casting, centrifugation, ultraviolet light crosslinking and drying demolding. The microneedle extraction and gold nano bipyramid color development integrated scheme is initiated, blood sampling is not needed, the dermis interstitial fluid is extracted in a minimally invasive mode through the microneedle, detection pain and trauma are reduced, the cross infection risk of blood treatment is avoided, and the microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle microneedle

The invention discloses a preparation method of platinum-based multi-metal aerogel and application of the platinum-based multi-metal aerogel in an electro-catalysis hydrogen evolution reaction. The method comprises the following steps: firstly, sequentially adding platinum salt and other metal salts into pure water, uniformly mixing, then adding a sodium borohydride solution, uniformly mixing, quickly freezing the reaction solution with liquid nitrogen, melting to obtain wet gel, and then washing and drying the wet gel to obtain the aerogel. The obtained metal aerogel is applied to a hydrogen evolution electrocatalyst and shows excellent catalytic activity under an alkaline condition. The preparation method has the advantages that the synthesis process is simple, convenient and efficient, regulation and optimization of an electronic structure can be realized through interaction among multiple metals, so that the catalytic performance is improved, the porous structure of the aerogel effectively provides a high-speed mass transfer channel, the catalytic activity is improved, and the preparation method is suitable for industrial production. And a solid foundation is laid for wide application of the metal aerogel material in the field of industrial chemical engineering.

The invention discloses a synthesis method of 2, 4, 5-trifluorophenylacetic acid, which comprises the following steps: by taking cheap and easily available o-chloronitrobenzene as a raw material, reacting with sodium nitrate in a sulfuric acid and trifluoroacetic acid system, separating generated 2, 4-dinitrochlorobenzene through melt crystallization, and continuing to synthesize 2, 4-dinitrochlorobenzene in methyl chloroacetate to obtain 2, 4, 5-trifluorophenylacetic acid. The method comprises the following steps: carrying out indirect aromatic nucleophilic substitution reaction on 2, 4-dinitrophenylacetic acid under the condition of sodium hydride to generate 5-chloro-2, 4-dinitrophenylacetic acid methyl ester, separating, carrying out fluorination reaction on the 5-chloro-2, 4-dinitrophenylacetic acid methyl ester and potassium fluoride under the action of a phase transfer catalyst, carrying out rectification separation to obtain 2, 4, 5-trifluorophenylacetic acid, and carrying out hydrolytic acidification on the 2, 4, 5-trifluorophenylacetic acid in a sodium hydroxide aqueous solution to obtain 2, 4, 5-trifluorophenylacetic acid. And the process route is safer, more environment-friendly, more efficient and lower in cost.

The present invention discloses a nano copper-based catalyst, its preparation method, and its application in the electrocatalytic reduction of carbon dioxide and carbon monoxide. Copper chloride (or copper nitrate, copper acetate) is dissolved in ultrapure water, and a sodium borohydride solution is added dropwise. Stir at room temperature for 5-60 min, filter, and dry to obtain a nano copper catalyst. Further, through a displacement reaction, nano copper-palladium and copper-silver catalysts are obtained. The present invention is applied to the electrocatalytic reduction of carbon monoxide. In a membrane electrode assembly (MEA) electrolyzer, the Faraday efficiency of multi-carbon products (C2+) reaches up to 95%, the partial current density reaches up to 3 A cm-2, and the overall electrolyzer energy efficiency reaches up to 39%. It can stably electrolyze for 30 hours at 1 A cm-2. This nano copper catalyst is applied to the electrocatalytic reduction of carbon dioxide. In an MEA electrolyzer, the Faraday efficiency of C2+ reaches up to 66%, and the partial current density reaches up to 331 mA cm-2.

The invention discloses an amino alcohol nickel complex as well as a preparation method and application thereof, and belongs to the technical field of organic metal synthesis. The molecular formula of the amino alcohol nickel complex is Ni [OCR1R2 (CH2) mNR3R4] 2, comprising the following raw materials: a nickel-containing complex, 60wt.% of NaH and HOCR1R2 (CH2) mNR3R4, the preparation method specifically comprises the following steps: (1) under the protection of nitrogen, mixing a nickel-containing complex, 60wt.% NaH, HOCR1R2 (CH2) mNR3R4 and toluene, carrying out heating reaction, and carrying out heating reaction again; and (2) filtering, concentrating, cooling, filtering again, and washing to obtain the product. The nickel-containing complex, sodium hydride and amino alcohol are synthesized into the amino alcohol nickel complex through a one-pot method, the raw materials are simple, easy to obtain and convenient to store, expensive active intermediates do not need to be synthesized or purchased, and the cost and risk of amplified production are reduced. Meanwhile, the purification method of the product is improved, the high-purity amino alcohol nickel complex is obtained through a low-temperature crystallization method, operation is safe and convenient, the industrial purification efficiency is improved, and the purity of the obtained product is as high as 6N-7N through ICP-MS testing.

The invention discloses a seawater initiation preparation method of metal wet gel and aerogel and application of the seawater initiation preparation method in electro-catalysis ethylene glycol oxidation. Comprising the following steps: 1) sequentially adding a metal salt, sodium citrate and a reducing agent into pure water, 2) adding seawater into a reaction solution to obtain wet gel, and 3) washing and drying the wet gel to obtain the aerogel. Seawater can be used for replacing expensive drugs used in a large amount in a salting-out method and an excessive sodium borohydride method, so that the metal nanoparticle solution is unstable, the metal aerogel material is prepared, and the preparation cost of the metal aerogel is greatly reduced. The metal aerogel obtained by the invention shows excellent catalytic performance in the application of electro-catalysis of ethylene glycol oxidation.

The invention discloses a synthesis method of N, N '-bis-(2, 2, 6, 6-tetramethyl-4-piperidyl)-1, 6-hexamethylenediamine, which comprises the following steps: dropwise adding hexamethylenediamine into a mixture of 2, 2, 6, 6-tetramethyl-4-piperidone and an organic solvent, heating to react, cooling after the reaction is completed, adding a sodium borohydride solid into the mixture in batches, and heating to continue the reaction, so as to obtain the N, N'-bis-(2, 2, 6, 6-tetramethyl-4-piperidyl)-1, 6-hexamethylenediamine, namely the N, N '-bis-(2, 2, 6, 6-tetramethyl-4-piperidyl)-1, 6-hexamethylenediamine. After the reaction is finished, decompressing and spin-drying; the preparation method comprises the following steps: adding 1, 2, 6, 6-tetramethyl-4-piperidinyl-1, 6-hexamethylenediamine into an organic solvent, pulping residues, filtering, washing a filter cake with dichloromethane, combining filtrate, and spin-drying to obtain the N, N '-bis-(2, 2, 6, 6-tetramethyl-4-piperidinyl)-1, 6-hexamethylenediamine. The molar ratio of the 2, 2, 6, 6-tetramethyl-4-piperidone to the hexamethylenediamine to the sodium borohydride is (2.0 to 2.1): 1.0: (1.2 to 2.5); sodium borohydride is adopted to replace a traditional noble metal catalyst, high-pressure hydrogenation reaction is avoided, reaction conditions are mild, operation is safe, and cost is low; the purity and the yield of the product are effectively improved.

A method for hydrogen (H2) generation includes contacting a graphite-phase carbon nitride cobalt oxide and magnesium aluminum oxide nanocomposite (g-C3N4@CoO / MgAl2O4) with sodium borohydride (NaBH4) in water (H2O) and hydrolyzing the sodium borohydride to generate hydrogen. The g-C3N4@CoO / MgAl2O4 nanocomposite comprises a graphite-phase carbon nitride (g-C3N4) in an amount of 5 to 15 percent by weight (wt. %), cobalt oxide in an amount of 1 to 10 wt. %, and magnesium aluminum oxide (MgAl2O4) in an amount of 75 to 95 wt. % based on a total weight of the g-C3N4@CoO / MgAl2O4 nanocomposite.

This application provides a method for preparing compound I-b or a pharmaceutically acceptable salt thereof, wherein (S)-N-methylamino-1-(2-thiophene)-1-propanol reacts with 4-fluorobenzo[1,3]dioxolane in a system containing sodium hydride and potassium benzoate to obtain compound I-b. This method has short steps, mild reaction conditions, and is simple to operate, making it suitable for industrial scale-up; moreover, the obtained product has high purity and low isomer content.

The invention relates to the technical field of chemical synthesis, and discloses a method for preparing 2, 5-furandicarboxylic acid, which comprises the following steps: dispersing cobalt nitrate and nickel sulfate into an aqueous solution of polyvinylpyrrolidone at room temperature; adding a sodium borohydride solution to obtain nano colloid; preparing an aqueous suspension of cerium oxide, and adding the aqueous suspension into the nano colloid; centrifugally filtering, and recovering a solid product; washing the solid product; centrifuging, putting solid powder obtained after centrifuging into a drying oven, and drying; and calcining and grinding the solid powder to finally prepare the Co-Ni / CeO2 catalyst. And dissolving 5-hydroxymethylfurfural in water at normal temperature, adding the prepared Co-Ni / CeO2 catalyst and a sodium hypochlorite solution, reacting, and filtering to remove the catalyst, thereby obtaining the 2, 5-furandicarboxylic acid. The method disclosed by the invention has the advantages of no use of strong base, low reaction temperature, short reaction time, few byproducts, greenness and sustainability.

The invention relates to the technical field of medicines, in particular to a preparation method of calcium L-5-methyltetrahydrofolate. According to the method, N-(4-aminobenzoyl)-L-glutamic acid, 2, 4, 5-triamino-6-hydroxypyrimidine sulfate and propane trihalide are adopted as starting raw materials, and tetrahydrofolic acid is synthesized through a one-pot method; compared with synthesis of L-5-methyl calcium tetrahydrofolate by using high-purity folic acid as an initial raw material, the process route does not involve use of chemical reagents such as sodium borohydride, zinc powder and some noble metal catalysts any more, the reaction is easier to control, the cost is lower, the safety is higher, the method is more environmentally friendly, and industrial production is easier to carry out.

The invention relates to a RuSe2-MoSe2 / NF heterojunction bifunctional catalyst for fully hydrolyzed seawater as well as a preparation method and application of the RuSe2-MoSe2 / NF heterojunction bifunctional catalyst, and belongs to the technical field of seawater electrolysis electrocatalysis. The preparation method of the bifunctional catalyst comprises the following steps: (1) mixing deionized water and absolute ethyl alcohol, and magnetically stirring to obtain a mixed solvent; then adding sodium borohydride and selenium powder into the mixed solvent, and stirring until the mixture is completely dispersed to obtain a mixed solution; adding sodium molybdate dehydrate and ruthenium trichloride into the mixed solution, introducing high-purity nitrogen, replacing air, and continuing magnetic stirring to obtain a dark brown precursor mixed solution; and (2) completely immersing the pretreated nickel foam NF in the precursor mixed solution, carrying out hydrothermal reaction, cooling to room temperature after the reaction, taking out the nickel foam NF, washing with deionized water for 3-5 times, then washing with absolute ethyl alcohol for 3-5 times, and drying to obtain the nickel foam NF. The bifunctional catalyst provided by the invention can efficiently catalyze a hydrogen evolution reaction and an oxygen evolution reaction in seawater at the same time.

The invention relates to the technical field of high-molecular polymer synthesis, and particularly discloses a cracking method of high-alkalinity polysulfide rubber latex, which comprises the following steps: S1, carrying out mother liquor separation on polysulfide rubber latex, and then washing for 0-2 times to obtain the high-alkalinity polysulfide rubber latex; and S2, cracking the high-alkalinity polysulfide rubber latex into liquid polysulfide rubber by using a cracking agent composed of sodium sulfite, sodium hydrogen sulfite and sodium hydrosulfide, wherein the molecular weight of the liquid polysulfide rubber is 1000-5000. Compared with the prior art, the cracking agent composed of sodium sulfite, sodium hydrogen sulfite and sodium hydrosulfide is adopted, high-alkalinity polysulfide rubber latex can be cracked, the washing frequency is reduced, the process efficiency is improved, and the overall polysulfide rubber production efficiency is indirectly improved; meanwhile, the wastewater discharge amount is reduced, and the subsequent wastewater treatment cost is reduced. The raw materials required by the cracking agent are easy to obtain and low in cost.

The invention relates to the technical field of carbon black, in particular to a production process for improving conductivity of carbon black, which comprises the following steps: activating carbon black with carbon dioxide, then treating with nitric acid to obtain a porous carbon black material, treating the porous carbon black material with a mixed amino acid solution to obtain a carbon black material loaded with a mixed amino acid adsorption layer; then adding a silver nitrate solution, stirring and mixing, dropwise adding a sodium borohydride solution, controlling the reaction temperature and pH, and filtering, washing and drying after the reaction is finished, so as to obtain a high-conductivity carbon black product. By adopting the production process, the conductivity of the carbon black can be greatly improved.

The invention relates to the technical field of polyphenylene sulfide, in particular to low-molecular-weight polyphenylene sulfide low in chlorine and easy to purify and a preparation method thereof.The method comprises the steps that 1, sodium hydroxide, sodium acetate and sodium hydrosulfide with the required amount are sequentially put into a reaction kettle, then N-methyl pyrrolidone is added, and heating dehydration is conducted under nitrogen protection to obtain a mixed solution; step 2, adding preheated paradichlorobenzene into the mixed solution, adding a part of phase control agent at the required polymerization temperature and under the protection of nitrogen, and carrying out prepolymerization stage reaction; and step 3, after the prepolymerization stage is completed, carrying out segmented temperature control on the reaction system, adding the residual phase control agent, carrying out polymerization stage reaction, and after the reaction is completed, obtaining the low-molecular-weight polyphenylene sulfide which is low in chlorine and easy to purify. The low molecular weight polyphenylene sulfide with low chlorine radical residue and low ash content is prepared, the phase control agent is easy to prepare and low in price, and the preparation method is easy and convenient to operate and convenient to popularize and apply.

The invention provides a preparation method of a magnetic recoverable catalyst and a method for synthesizing 3-mercaptopropionic acid, and mainly solves the problem that a large amount of acid and alkali solutions are needed in the existing acrylonitrile-sodium hydrosulfide and acrylic acid-thiourea process routes. The thiohydracrylic acid synthesis catalyst is prepared. The use conditions of the catalyst are as follows: the temperature is 30-80 DEG C, the reaction pressure is 0.5-3 MPa, the mass ratio of the acrylic acid to the solvent is 0.1-5, and the mass ratio of the acrylic acid to the catalyst is 0.2-20. Compared with the prior art, the catalyst disclosed by the invention is used as a synthetic catalyst for preparing thiohydracrylic acid through reaction of acrylic acid and hydrogen sulfide, a solid catalyst and a liquid reaction system can be completely separated by adopting simple methods such as filtration, centrifugation or magnetic separation, and a complicated pickling step is not needed; and the problem that a homogeneous catalyst is difficult to rectify after salification in the use process is avoided.

The invention discloses a preparation method of an MF (at) NH2 (at) Ag SERS (Surface Enhanced Raman Scattering) sensor for detecting paraquat and diquat, belongs to the field of nano material synthesis and spectral analysis, and solves the problems that a traditional detection method is complicated in process and cannot detect pesticides and free radicals thereof at the same time, and a traditional SERS substrate is poor in enhancement effect and low in stability. The preparation method comprises the following steps: firstly segmenting melamine foam, cleaning and drying, soaking in hydrochloric acid, soaking in a polyethyleneimine aqueous solution to modify amino, drying, soaking in a silver nitrate solution for ultrasonic treatment, adding a sodium borohydride solution under an ice bath, stirring and reducing, and finally cleaning and drying to obtain the sensor. The sensor takes three-dimensional melamine foam as a support, silver nanoparticles are uniformly loaded on the surface of the three-dimensional melamine foam, paraquat, aquacide and free radicals thereof are enriched through electrostatic interaction based on a localized surface plasma resonance principle, and Raman signal enhancement is realized. The detection limit is 10 <-9 > mol / L, the signal stability and repeatability are excellent, the applicability to actual water sample detection is good, the detection of other pesticides can be expanded, and the method is suitable for on-site rapid trace detection.

The invention discloses preparation and application of a heterogeneous element doped oxide composite catalyst. The preparation method comprises the following steps: stirring an iron source, carbon nanotubes and triton in a solvent, adding a sodium borohydride solution at 2-10 DEG C, and rapidly stirring and uniformly mixing; aging the solution at 2-10 DEG C, collecting a sample, washing and drying; carrying out heat treatment to obtain a gamma-Fe2O3 precursor loaded on the carbon nano tube; stirring the gamma-Fe2O3 precursor loaded on the carbon nano tube and a heterogeneous element source in a solvent, evaporating to dryness and grinding; and performing heat treatment to obtain the composite catalyst. The gamma-Fe2O3 and carbon nanotube in-situ loaded composite material is used as a precursor, the structural stability of the substrate is effectively improved, meanwhile, the intrinsic catalytic activity of the gamma-Fe2O3 can be effectively improved through doping of multi-element heterogeneous elements, and compared with a fractional-step doping strategy, higher catalytic activity and higher utilization value are shown.

The application belongs to the technical field of fluorescent probe detection, and discloses a bimetallic nanocluster fluorescent probe compound and application thereof in preparation of a product for rapidly detecting acetylene. The fluorescent probe compound is a gold-copper bimetallic nanocluster solution modified by adamantane thiol, which is used as a fluorescent probe for acetylene detection. The solution has a clear and controllable preparation process. Through specific proportioning and reaction conditions of cuprous chloride, adamantane thiol, tetrachloroauric acid, sodium borohydride and other reagents, a probe solution with stable fluorescence characteristics can be prepared. The bimetallic nanocluster fluorescent probe compound is applied in preparation of a product for rapidly detecting acetylene. Through specific combination of fluorescent molecules and acetylene gas to trigger the secondary effect of fluorescence quenching, detection is realized, and other substances cannot trigger quenching. At a wavelength of 700 nm, the linear relationship (R 2 >0.99) between the fluorescence intensity and the acetylene concentration realizes accurate quantification of the acetylene concentration, and the minimum detection limit is 0.026 muL / L.

The invention belongs to the technical field of hydrogen production, and discloses a preparation method of a nickel-based catalyst based on expanded graphite dispersion and application of the nickel-based catalyst in ammonia cracking hydrogen production, and the preparation method comprises the following steps: (1) uniformly dispersing expanded graphite in deionized water; (2) adding nickel chloride hexahydrate and cerium chloride heptahydrate to be uniformly dispersed on the surface of the expanded graphite; (3) adding sodium borohydride into the mixture for reduction, centrifugation and washing; (4) calcining the solid obtained by centrifugation, oxidizing and crystallizing Ce (III) in a high-temperature environment to form CeO2; and (5) reducing under a pure hydrogen condition to obtain the Ni / CeO2-expanded graphite catalyst. The catalyst is a three-dimensional precursor formed by nickel chloride, cerium chloride and expanded graphite through a reduction method, Ni and CeO2 are dispersed and fixed on the expanded graphite, and the catalyst shows excellent catalytic activity in an ammonia decomposition reaction through a confinement effect of the expanded graphite and an electron transfer synergistic effect.

The utility model relates to the technical field of chemical engineering, in particular to a sodium hydrogen sulfide solution storage tank flushing system which comprises a magnetic turning plate liquid level meter, a remote transmission liquid level meter, a sodium hydrogen sulfide storage tank, a condensation water pipeline, an upper flushing line, a lower flushing line and a remote transmission flushing line. A lower end inlet of the magnetic flap liquid level meter is connected with a lower end drain valve; a first short-circuit wire is led out from the sodium hydrosulfide storage tank to be connected to an outlet in the upper end of the magnetic flap liquid level meter, a second short-circuit wire is led out from the sodium hydrosulfide storage tank to be connected to an outlet in the lower end of the magnetic flap liquid level meter, a third short-circuit wire is led out from the sodium hydrosulfide storage tank to be connected to the remote transmission liquid level meter, and a remote transmission shower valve is arranged on the third short-circuit wire. On-line flushing of the sodium hydrogen sulfide solution storage tank is achieved, when liquid level display is different from remote liquid level, water flushing is carried out, checking is carried out again after flushing, and the operation risk is reduced.

The invention discloses a nano SiO2 composite iron microsphere toughening agent for well cementation cement, and belongs to the technical field of petroleum and natural gas well cementation engineering materials. The preparation method of the flexibilizer comprises the following steps: adding ferric trichloride into ethylene glycol, and stirring and dissolving at normal temperature to obtain a solution A; the preparation method comprises the following steps: adding polyvinylpyrrolidone into ethylene glycol, stirring and dissolving at a certain temperature to obtain a solution B, and then adding sodium citrate to prepare a solution C; tetraethoxysilane is added into deionized water and then mixed with the solution A, a hydrolysis reaction of tetraethoxysilane is carried out, and a solution D with nano SiO2 is prepared; gradually and slowly dropwise adding the solution D into the solution C at a certain temperature, and carrying out a first oxidation-reduction reaction; cooling to room temperature, adding sodium borohydride, and carrying out a second oxidation-reduction reaction; and filtering, washing and drying the solution to obtain the flexibilizer. The cement stone is endowed with high toughness and compressive strength through the synergistic effect of the iron elementary substance and the nano SiO2, and the cement stone has a wide market prospect.

The present invention relates to a preparation method and application of a black soldier fly worm sand biomass carbon-based solid acid catalyst. The preparation method comprises the following steps: first, the black soldier fly worm sand is sieved with a sieve, and then the sieved black soldier fly worm sand is added to a sodium hydrosulfide solution and stirred and soaked for several hours. The pretreated black soldier fly worm sand is washed three times with deionized water and dried in an oven for 24 hours. Finally, the pretreated and dried worm sand is pyrolyzed and carbonized at high temperature in a nitrogen atmosphere for several hours to obtain a biochar-based solid acid catalyst material. The present invention uses biomass worm sand as raw material, which is cheap and easily available, reduces the production cost of solid acid catalysts and biodiesel, and improves the utilization value of renewable resources. In the present invention, the carbon-based material is pretreated with a sodium hydrosulfide solution, which not only improves the acid catalytic activity of the catalyst, but also improves the pore structure of the catalyst, thereby improving the catalytic activity of the carbon-based material as a whole, and is expected to become a highly competitive clean process route.

The invention provides a core-shell quantum dot preparation method, which comprises: S1, mixing a quantum dot core-containing dispersion liquid, a first ligand, an additive, an etching agent and a first non-coordination solvent in a container, and carrying out a reaction for a certain time at a temperature of 150-200 DEG C to obtain an intermediate product system containing a surface-etched quantum dot core; the additive is selected from at least one of metal zinc, metal magnesium, sodium hydride, calcium hydride, potassium hydride, lithium aluminum hydride, sodium borohydride, a molecular sieve, calcium chloride, magnesium sulfate and sodium sulfate; s2, raising the temperature of the intermediate product system to a first temperature, adding an anion precursor and a zinc precursor into the container, and reacting for a certain time to obtain core-shell quantum dots; the anion precursor comprises at least one of a selenium precursor and a sulfur precursor; wherein the first temperature is selected from 250-340 DEG C. According to the preparation method, the size uniformity of the core-shell quantum dot after the shell layer is coated is better, so that the fluorescence half-peak width is narrowed.

The invention discloses a preparation method of a bilastine intermediate, which comprises the following steps: reacting a compound 5 with thionyl chloride under the conditions that dichloromethane is used as a solvent and DMF (Dimethyl Formamide) is used as a catalyst to generate acyl chloride, and then reacting the acyl chloride with diethylamine to prepare a compound 6; taking dichloromethane as a solvent, and carrying out Friedel-Crafts acylation on the compound 6 and ethyl oxalyl chloride under the condition of anhydrous aluminum trichloride to obtain a compound 7; reducing the compound 7 by using sodium borohydride, liquid caustic soda and a water system to prepare a compound 8; taking dichloromethane as a solvent, and reducing the compound 8 by TMDS under the condition of anhydrous aluminum trichloride to prepare a compound 9; hydrolyzing the compound 9 under the hydrochloric acid condition to obtain a compound 10; and under the condition of thionyl chloride, carrying out esterification reaction on the compound 10 and methanol to prepare the bilastine intermediate TM. The preparation method of the bilastine intermediate, provided by the invention, has the advantages of economical and easily available raw materials, mild reaction conditions, efficient reaction and simple operation, and is suitable for industrial application.

This invention provides a compound for recognizing chiral amino alcohols, a fluorescent probe, its preparation method, and its application. Naphthol and sodium hydride are weighed and dissolved separately in ultra-dry tetrahydrofuran, mixed, and then reacted with bromomethyl methyl ether. The mixture is extracted with ethyl acetate, and the organic phases are combined to obtain product (R)-1. This product is dissolved in ultra-dry tetrahydrofuran, and n-butyllithium is added. The reaction system changes from colorless to brown, and the reaction is allowed to return to room temperature. Ultra-dry N,N-dimethylformamide solution is then added, and the reaction is quenched by adding saturated ammonium chloride solution under ice-water bath conditions. The product is then extracted with ethyl acetate to obtain product (R)-2. Product (R)-2 is dissolved in a mixed solvent of tetrahydrofuran and anhydrous methanol, and sodium triacetoxyborohydride is added. The product is then extracted with ethyl acetate to obtain reduced product (R)-3. Product (R)-3 is dissolved in a mixed solvent of dichloromethane and anhydrous ethanol, and concentrated hydrochloric acid is added. After the reaction is complete, the reaction is quenched with sodium bicarbonate, and then extracted with dichloromethane to finally obtain compound (R)-4, which recognizes chiral amino alcohols.

This invention discloses a method for preparing and applying a sodium borohydride-modified self-supporting anode for AEM water electrolyzers. Firstly, an amorphous ternary metal hydroxyl oxide precursor is grown in situ on a nickel substrate via room temperature liquid phase deposition. The process involves the presence of Co in solution. 2+ Fe 3+ Ni ions are introduced through slight corrosion of the nickel foam matrix. 2+ The ions, the three, and the OH- produced by hydrolysis ⁻ Co-deposition occurs under the influence of dissolved oxygen, leading to the self-assembly of amorphous nanosheet structures on the substrate surface. Subsequently, a mild chemical reduction treatment with sodium borohydride solution is used to obtain a structurally stable and high-performance self-supporting electrode. The method described in this embodiment is mild, simple, low-cost, and has good versatility.

The present invention relates to the technical field of drug intermediate synthesis, and particularly relates to a preparation method of posaconazole starting material SM3. CeCl3·7H2O and sodium borohydride are added to compound POS-1 for an asymmetric reduction reaction to obtain compound POS-2. Compound POS-2 reacts with 3,5-bis(trifluoromethyl)benzenesulfonyl chloride to obtain compound POS-3. Hydrazine hydrate attacks from the back of compound POS-3 with a larger steric hindrance to undergo an SN2 reaction to obtain a stereoselectively specific compound POS-4. Compound POS-4 then reacts with ethyl formate and forms a salt with oxalic acid to obtain the product posaconazole starting material SM3. By means of asymmetric reduction of carbonyl groups and selective nucleophilic substitution, the present invention effectively avoids the chiral resolution step, thereby reducing the content of isomeric impurities. The prepared product not only has a high ee value, but also the yield is significantly improved, thereby greatly reducing the production cost.

The invention relates to the technical field of chemical material preparation, and particularly discloses a safe preparation method of a short fluorocarbon alkyl sulphobetaine surfactant, a product and application, and the safe preparation method comprises the following steps: (1) in a solvent system I, reacting epoxy chloropropane with secondary amine to obtain an intermediate 1; (2) in a solvent system II, reacting the intermediate 1 with sodium hydrosulfide or a hydrate thereof to obtain an intermediate 2; (3) reacting the intermediate 2 with short fluorocarbon alkyl iodide to obtain perfluoroalkyl thioether propyl tertiary amine; and (4) carrying out sulfonation treatment on perfluoroalkyl thioether propyl tertiary amine to obtain the short-fluorocarbon alkyl sulphobetaine surfactant. According to the invention, by designing a synthetic route without using a high-risk reagent, the safety and operability of the process are remarkably improved, and the sulphobetaine surfactant with excellent acid, alkali and salt chemical stability and excellent surface activity is successfully prepared; and a key material and a safe and reliable preparation process are provided for development of a new-generation efficient environment-friendly fire extinguishing agent.