578 results about "Sodium borohydrate" patented technology

The invention relates to a metallized microbubble and a preparation method thereof, a construction method of a multifunctional composite probe, and a rapid bacterium capturing and sterilizing method, and belongs to the technical field of functional material preparation. The method aims at solving the technical problems that in the prior art, a metal coating on the surface of the hollow glass microbubble is not uniform, combination is not firm, and stability is poor. According to the technical scheme, the method is characterized by comprising the following steps: mixing surface-activated hollow glass microbubbles with a polyethyleneimine solution for reaction, and washing and drying to obtain polyethyleneimine-coated hollow glass microbubbles; then reacting with a single-stranded DNA buffer solution to obtain an intermediate product loaded with DNA; then introducing a silver nitrate solution to load silver ions on the surface of the compound; and finally, reducing through a sodium borohydride solution to prepare the metallized microbubbles. The metalized microbubbles prepared by the method can be used for constructing a multifunctional composite probe to realize efficient capture and synergistic antibiosis of targets such as bacteria.

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 method for rapidly determining the content of breast milk oligosaccharide in dairy products, which comprises the following steps: sampling and pretreating different types of dairy products according to sample states, carrying out ultrasonic extraction, refrigerated centrifugal degreasing and centrifugal ultrafiltration protein purification on the obtained sample, and reducing the purified sample solution by using sodium borohydride to obtain a sample solution to be detected; reducing the breast milk oligosaccharide standard substance by sodium borohydride to obtain a standard solution to be detected; determining the standard substance solution and the to-be-detected sample solution by adopting ultra-high performance liquid chromatography-tandem mass spectrometry, establishing a standard curve, and carrying out quantitative analysis on the to-be-detected sample solution; the chromatographic conditions are as follows: an ACQUITY UPLC BEH Amide hydrophilic interaction chromatographic column is adopted; the mobile phase A is 20 mmol / L ammonium formate; the mobile phase B is acetonitrile; and gradient elution.

The preparation method comprises the following steps: (1) fish skin pretreatment: (2) gas foaming treatment: weighing sodium borohydride with a certain molar concentration, dissolving the sodium borohydride in a phosphate buffer solution with a certain concentration, stirring until bubbles in the solution are obviously generated and most of solids are dissolved, and then, carrying out gas foaming treatment; putting the cleaned fish skin tissues in the step (2), and performing foaming treatment; (3) cleaning treatment; and (4) protection and storage. The gas foaming technology is innovatively adopted for decellularization treatment, the interface stripping effect between cells and a matrix is remarkably enhanced on the premise that the collagen three-dimensional structure and the scaffold morphology integrity are not damaged, and the method is suitable for the decellularization pretreatment process of soft tissue (such as fish skin and placenta) with a compact structure or cell-intensive type. The development of a biomedical material, especially a tissue engineering scaffold technology, is promoted, and the preparation method has a wide application prospect.

The invention belongs to the field of photocatalytic preparation of hydrogen peroxide, and relates to a novel secondary amine linked covalent organic framework material (AR-COF) as well as a preparation method and application thereof. According to the material, tetraaldehyde phenyl porphyrin and 2, 5-diamino-1, 4-benzenediol dihydrochloride are subjected to a Schiff base reaction to synthesize an imine bond connected porphyrinyl covalent organic framework (IM-COF), and then synthesis post-modification (PSM) is performed on the imine bond connected porphyrinyl covalent organic framework (IM-COF) so that the imine bond connected porphyrinyl covalent organic framework (IM-COF) and sodium borohydride can be subjected to a reduction reaction to generate AR-COF. The photocatalytic stability of the material is maintained through modification after synthesis, the catalytic activity is improved, and the original crystal structure is not damaged. A photocatalytic hydrogen peroxide production experiment shows that the catalytic activity of AR-COF under 420 nm monochromatic light is superior to that of IM-COF, the yield under an oxygen condition reaches 7.79 mmol.g <-1 >. H <-1 >, and hydrogen peroxide can be stably produced. The method utilizes solar energy for green synthesis under mild conditions, and provides a safe and efficient method for hydrogen peroxide production.

The invention discloses a modified microfiltration membrane for enriching biological particles and a preparation method and application thereof, and belongs to the technical field of biological separation.The preparation method of the modified microfiltration membrane comprises the following steps that a mixed cellulose ester microfiltration membrane is provided and subjected to alkali liquor activating treatment; placing the activated membrane in a weakly alkaline buffer solution for balancing; the preparation method comprises the following steps: in a weakly alkaline buffer solution, firstly contacting the surface of the membrane with a tannic acid solution to carry out a first reaction, and then directly adding a polyethyleneimine solution to carry out a second reaction under the condition of not replacing a system, so as to form a phenol-amine cross-linked network on the surface of the membrane in situ; sodium cyanoborohydride is continuously added for reduction stabilization treatment, and the modified microporous filter membrane is obtained. The modified microporous filter membrane prepared by modifying the microporous filter membrane with tannic acid and polyethyleneimine can realize one-step synchronous enrichment of all negatively charged targets, and the problems of target loss, efficiency loss and the like caused by a multi-step process are avoided from the source.

The application provides a kind of superfine copper powder and its preparation method and application, the preparation method of the above-mentioned superfine copper powder uses two-step liquid phase reduction method to prepare superfine copper powder, and improves process conditions, using dropwise feeding mode. Among them, the first step uses alkaline ascorbic acid solution to reduce copper chloride to cuprous chloride with narrow particle size distribution; the second step uses ferrous sulfate and sodium citrate as mixed reducing agent, and sodium citrate can also be used as a complexing agent, which helps to reduce the cuprous chloride to spherical, well-dispersed, uniform particle size distribution of superfine copper powder. At the same time, the raw materials used by the application are easy to obtain, the reaction process is mild, and organic solvents and toxic and hazardous reagents such as sodium borohydride and hydrazine hydrate are not needed, the preparation process has cost effectiveness, is friendly to the environment, and is suitable for industrial production.

The invention discloses a nitrogen / boron-doped non-noble metal-based material, a synthesis method thereof and application of the nitrogen / boron-doped non-noble metal-based material in a microbial fuel cell. According to the method, a carbon fiber brush is used as a substrate, urea and sodium borohydride are used as a nitrogen source and a carbon source respectively, and the nitrogen / boron doped non-noble metal-based material is synthesized through a hydrothermal method. The electrostatic interaction between graphene oxide and FeCoNi-LDH is utilized to realize tight combination, so that FeCoNi-LDH nanosheets are uniformly dispersed on the surface of the carbon fiber brush, and the problems that LDHs are easy to agglomerate and poor in conductivity are solved; in the boron / nitrogen co-doping process, an efficient electron transmission channel is constructed by adjusting the electronic structure of the composite material, and the material is endowed with excellent electron transmission capability and oxygen reduction performance. In an MFC (Microbial Fuel Cell) test constructed by taking a nitrogen / boron-doped non-noble metal-based material as a cathode, the output voltage and the maximum power density are several times of those of commercial Pt / C and a blank carbon fiber brush, and the carbon fiber brush has a wide application prospect in the field of microbial fuel cells.

The invention discloses a method for detecting aflatoxin B1 in coffee based on colorimetric and photo-thermal dual modes of MXene (at) Pt nano-enzyme, which comprises the following steps: etching Ti3AlC2 by using LiF and HCl to obtain MXene, synthesizing platinum nano-particle modified MXene nano-enzyme (MXene (at) Pt) by using dopamine carbon dots and sodium borohydride as reducing agents and adopting an in-situ reduction technology, and detecting aflatoxin B1 in coffee by using the MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt). The MXene (at) Pt shows near-infrared light stimulation enhanced peroxidase-like activity and photo-thermal performance and can catalyze blue deepening and temperature rising of a substrate 3, 3 ', 5, 5'-tetramethyl benzidine (TMB), when aflatoxin B1 exists, POD-like activity of MXene (at) Pt nano-enzyme is inhibited, and colorimetric and temperature signals are reduced; a method for detecting the AFB1 by the colorimetric temperature dual-mode sensor is established, and the method has the characteristics of high sensitivity, strong specificity, simplicity and rapidness in operation and the like.

The invention discloses a liquid metal-based catalyst with flowable amorphous cobalt active sites as well as a preparation method and application of the liquid metal-based catalyst. The spherical gallium-based liquid metal loaded amorphous cobalt nanosheet material is synthesized by using a sodium borohydride ice bath method. Due to the optimization of the synthesis process, the amorphous cobalt nanosheets are uniformly distributed on the surfaces of the liquid gallium balls, are small in size, are high in utilization rate and are not easy to agglomerate; the intrinsic flow characteristic of the liquid metal gallium realizes the efficient reverse hydrogen overflow effect, optimizes the formation process of a catalytic reaction intermediate, and accelerates the formation of the intermediate. The composite material has the advantages of low overpotential, high Faraday efficiency, high ammonia production rate, good stability and the like during nitrate electrocatalytic reduction reaction, meets the requirements of production and use, and is low in preparation cost.

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.

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.

The invention discloses a divalent nucleic acid aptamer fluorescence detection method based on an exonuclease I auxiliary target circulation strategy, and belongs to the field of analysis and detection.The divalent nucleic acid aptamer is a repetitive sequence composed of two monovalent nucleic acid aptamers and can form double-stranded DNA through base complementary pairing with complementary strand cDNA of the divalent nucleic acid aptamer, and the divalent nucleic acid aptamer can be used for fluorescence detection of the divalent nucleic acid aptamer. The method comprises the following steps: taking a bivalent nucleic acid aptamer as a template, forming a DNA silver nanocluster (DNA-AgNCs) under the action of silver nitrate and sodium borohydride, and when the target okadaic acid exists, combining the bivalent nucleic acid aptamer with the target, so that cDNA can be replaced from double-stranded DNA by the target. Exonuclease I is added to perform enzyme digestion on the cDNA and the divalent nucleic acid aptamer, so that the fluorescence intensity of the DNA-AgNCs can be rapidly reduced. The content of the okadaic acid can be judged by detecting the change of the fluorescence intensity. The invention provides a simple, convenient, rapid, high-sensitivity and high-specificity detection method for okadaic acid detection based on a divalent nucleic acid aptamer for the first time.

The preparation method comprises the following steps: adding MnO2 into deionized water, carrying out uniform ultrasonic dispersion, adding RuCl3.xH2O, carrying out uniform ultrasonic dispersion, slowly dropwise adding an excessive amount of a sodium borohydride aqueous solution into the dispersed solution under vigorous stirring, continuously carrying out a stirring reaction for 3-5 h after the dropwise addition is completed, and after the reaction is completed, carrying out filtration, washing and drying to obtain the Ru / Mn3O4-x hydrogen evolution electrocatalyst. And centrifuging and collecting solids, sequentially washing and drying, fully grinding the obtained sample, transferring to an inert gas atmosphere at 300-500 DEG C, and calcining for 1-2 hours to obtain the Ru / Mn3O4-x hydrogen evolution electrocatalyst. The Ru / Mn3O4-x hydrogen evolution electrocatalyst prepared by a wet chemical reduction method has good intrinsic activity and good electrochemical performance, the process is simple, the cost is low, and a new thought is provided for reasonably constructing a ruthenium-based electrocatalyst to improve the electrocatalytic activity.

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 discloses a microbial soil conditioner and a preparation method thereof, and relates to the technical field of soil improvement. The method comprises the following steps: culturing heavy metal-resistant chlorella and aspergillus niger to obtain a mixed bacterial suspension, combining the mixed bacterial suspension with a composite chelating modifier prepared by reacting chitosan quaternary ammonium salt, ethylenediamine tetraacetic acid and epichlorohydrin, carrying out crosslinking by using genipin to obtain a functional microbial agent, and carrying out pyrolysis and acid oxidation on corn straws as a raw material to obtain the heavy metal-resistant chlorella modified functional microbial agent. The preparation method comprises the following steps: preparing a nano zero-valent iron-biochar composite material, reducing and loading ferrous ions through sodium borohydride, preparing the nano zero-valent iron-biochar composite material, mixing the nano zero-valent iron-biochar composite material with zeolite, bentonite and a silane coupling agent, carrying out spray drying to prepare a porous carrier substance, and finally stirring and mixing an organic fertilizer complex microbial inoculant, the functional microbial inoculant and the carrier substance, and aging to prepare the soil conditioner. The prepared conditioner has a good remediation effect on soil heavy metal pollution.

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 discloses a semi-open type deep sea subsurface buoy sodium borohydride fuel cell cabin which comprises a pressure-resistant shell, and a seawater desalination membrane separation device, an anode fuel raw material storage cabin, a spiral conveyor, an anode fuel dissolution reaction cabin, a direct sodium borohydride fuel cell, a cathode solution storage cabin, a waste liquid storage bag and a lithium battery are arranged in the pressure-resistant shell. The cruising ability of the deep-sea subsurface buoy is greatly improved, the operation ability boundary of the deep-sea subsurface buoy is greatly expanded, and an excellent solution thought is provided for the requirement of deep-sea long-period exploration operation of the base type subsurface buoy. Besides, the advantage of rich water resources in the marine environment is fully utilized, the sodium borohydride powder raw material with very stable physicochemical properties is carried, and seawater is continuously obtained as a solvent, so that the utilization rate of the internal space of the battery cabin is greatly improved.

The invention discloses a Karstedt catalyst and a preparation method thereof, and belongs to the technical field of catalysts. The preparation method provided by the invention comprises the following steps: firstly, chloroplatinic acid reacts with three different siloxanes to generate a zero-valent platinum complex, the siloxanes are tetradimethyl vinyl siloxy silane, tetramethyl divinyl disiloxane and 1, 3-dimethyl-1, 1, 3, 3-tetraethylene disiloxane, calcium oxide is added in the reaction to be matched with sodium bicarbonate to neutralize, and then the zero-valent platinum complex is obtained. And after the reaction, reducing residual bivalent platinum by using sodium borohydride, and finally loading by using an SBA15 molecular sieve as a carrier to obtain the finished product Karstedt catalyst. The multi-ligand Karstedt catalyst is formed by combining a tetradentate ligand, a conventional chain ligand and a branched chain polyvinyl ligand, the multi-ligand Karstedt catalyst has high catalytic activity and stability, the loading capacity and the loading binding force are improved through a network architecture of a complex configuration, the dosage of the supported catalyst is reduced, and the cyclic utilization rate is improved.

The invention discloses a universal synthesis method of medium-entropy / high-entropy alloy nanoparticles and application of the medium-entropy / high-entropy alloy nanoparticles. Comprising the following steps: 1) dissolving three or more metal precursor salts in deionized water according to a required molar ratio, and carrying out ultrasonic treatment until the salts are completely dissolved to obtain a metal precursor solution A; (2) adding polyvinylpyrrolidone into the solution A as a stabilizer, and uniformly stirring; 3) under a stirring condition, slowly dropwise adding 0.3-0.5 M of a sodium borohydride solution as a reducing agent into the solution A to form a reaction solution B; (4) carrying out constant-temperature reaction on the reaction liquid B at 60-80 DEG C for 4-5 hours to form uniform nano-particle colloid; and (5) centrifuging, washing and freeze-drying the nano-particle colloid to obtain black powdery alloy nano-particles. The reaction temperature of the preparation method is 1t; 90 DEG C; the overpotential of the alloy nanoparticles in the HER is lt; 10mA / cm < 2 > at 30mV.

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 discloses a synthesis method of 9-dichloromethylene-5-amino-benzonorbornene and an intermediate product, the synthesis method comprises the following steps: firstly, synthesizing a cyclization compound 1 as shown in a formula 1 from a cold solution of 6, 6-dichlorofulvene and 1, 4-benzoquinone under the action of a solution of a catalyst I, carrying out oximation reaction on the cyclization compound 1 prepared in the step a and hydroxylamine salt under an alkaline condition, and carrying out post-treatment to obtain the 9-dichloromethylene-5-amino-benzonorbornene. Under the action of a catalyst II, adding the oximate 2 prepared in the step b into a closed container, carrying out hydrogenation reduction to obtain 9-dichloromethylene-5-amino-benzo norbornene, and directly treating the reduction product with acid to obtain 9-dichloromethylene-5-amino-benzo norbornene, namely the 9-dichloromethylene-5-amino-benzo norbornene, namely the 9-dichloromethylene-5-amino-benzo norbornene. According to the method, the cyclization compound is oximated firstly, then the residual carbonyl and two double bonds on the ring are subjected to one-step reduction through catalytic hydrogenation, the working procedure is optimized, meanwhile, reduction by using expensive sodium borohydride is avoided, the method is short in synthesis route and suitable for industrialization, and the production cost is reduced.

The application discloses a preparation method of a core-shell structure type Ru / CeO2@COF catalyst, and the method comprises the following steps: firstly, spherical CeO2 particles are added into a polyethylene imine aqueous solution for surface treatment; secondly, the particles are added into anhydrous acetonitrile containing PVP, and then DMTP and TAPB are added, and glacial acetic acid is added for reaction at room temperature and heating reaction to obtain a core-shell type carrier material; and thirdly, after dispersion, RuCl3 methanol solution is added dropwise for ultrasonic treatment, and sodium borohydride solution is added dropwise for reduction to obtain the Ru / CeO2@COF catalyst. The core-shell structure type catalyst is prepared by coating COF on the surface of the spherical cerium oxide to construct a core-shell type carrier material and loading elemental Ru nanoparticles, the specific surface area of the cerium oxide surface is effectively increased, the adsorption capacity of the catalyst is enhanced, the conductivity of the catalyst is improved, and therefore the electrocatalytic activity and stability of the catalyst are improved, and the catalyst is suitable for the field of water electrolysis hydrogen evolution reaction.

The invention discloses a preparation method of 3-quinuclidinone hydrochloride, which comprises the following steps: carrying out temperature control reaction on 4-picolinic acid and chloroacetic acid under alkaline water conditions to obtain an aqueous solution of a compound a, and directly entering the next reaction without post-treatment after the reaction is finished; adding a reducing agent alkaline water system into the aqueous solution of the compound a, controlling the temperature to react, controlling the temperature to adjust the pH value to 5-5.5 after the reaction is finished, extracting with n-butyl alcohol, and drying to obtain an n-butyl alcohol solution of a compound b, and directly entering the next reaction step; wherein the reducing agent is one of sodium borohydride and potassium borohydride; dropwise adding thionyl chloride into an n-butyl alcohol solution of the compound b, controlling the temperature to react after dropwise adding is ended, and concentrating to remove the solvent and unreacted thionyl chloride after the reaction is ended, so as to obtain a compound c; carrying out Dieckmann condensation reaction on the compound c at controlled temperature under the condition of organic alkali by using toluene as a solvent, carrying out hydrochloric acid quenching reaction after the reaction is finished, and directly carrying out next-step reaction after extracting and removing impurities from a water phase containing a hydrochloride solution of a compound d by using toluene; and carrying out a decarboxylation reaction on the compound d in a hydrochloric acid aqueous solution at controlled temperature, after the reaction is finished, adjusting the pH value to 10-13, extracting, and salifying to obtain a target compound TM, namely 3-quinuclidinone hydrochloride. The preparation method of 3-quinuclidinone hydrochloride provided by the invention has the advantages of economical and easily available raw materials, mild reaction conditions, efficient reaction, simple operation and low cost, and is suitable for industrial application.

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 application relates to a method for high-sensitivity detection of Se(IV) based on an Au-MnO2-Pd NPs composite material, and belongs to the technical field of selenium detection. The detection method comprises the following steps: placing a to-be-detected solution containing Se(IV) and hydrochloric acid in a headspace bottle, placing a dispersion of the Au-MnO2-Pd NPs composite material on a headspace bottle cap, and injecting a reducing agent solution into the headspace bottle, and after reaction, liquid on the headspace bottle cap forms a to-be-detected mixed solution; the to-be-detected mixed solution is dropped and coated on the surface of a GCE electrode, then DPV is scanned in a test base solution, and qualitative and quantitative detection of Se(IV) is realized. In the application, Se(IV) in a sodium borohydride reducing solution is reduced to generate H2Se gas, the H2Se gas reacts with the Au-MnO2-Pd NPs composite material with electrochemical activity, a DPV signal is combined to drop, and high-sensitivity detection of Se(IV) in a solution is realized.