125 results about "Benzidines" patented technology

The invention discloses a preparation method of a carbon dot nano-enzyme, which comprises the following steps: dissolving oxalic acid, polyethyleneimine and ferric nitrate in ultrapure water, heating, mixing and reacting, cooling to room temperature, centrifuging, filtering, dialyzing, and taking supernate to obtain the carbon dot nano-enzyme. The prepared oxalic acid carbon dot nano-enzyme is matched with acetylcholin esterase, acetylcholine, 3, 3 ', 5, 5'-tetramethyl benzidine and H2O2 to construct a colorimetric and fluorescent dual-mode detection method for glyphosate in fruits and vegetables. The oxalic acid carbon dot nano-enzyme is prepared by doping ferric nitrate and tetraethylenepentamine into oxalic acid serving as a precursor, the oxalic acid carbon dot nano-enzyme has excellent peroxidase-like activity, a colorimetric and fluorescent dual-mode detection method of glyphosate is constructed through the oxalic acid carbon dot nano-enzyme, dual-mode detection results can be mutually verified, and the detection result is accurate. And the accuracy and the reliability of a detection result are remarkably improved.

The invention belongs to the technical field of polymer adsorbent materials, and particularly relates to an ionic polymer adsorbent material containing sulfonic groups and triazinyl, a preparation method and application thereof. A sulfonic acid group is introduced to a molecular structure unit of the nitrogen-rich polymer, and the specific surface area and the ion capacity of the polymer are controlled by adjusting the content of benzidine disulfonic acid; along with the increase of the proportion of benzidine disulfonic acid, the ion capacity of an adsorbent is gradually increased, the specific surface area is gradually reduced, the invention also discloses application of the ionic polymer containing sulfonic acid and triazinyl structure in dye adsorption, and the prepared polymer has high specific surface area, heat-resistant stability, adsorption performance and adsorption regeneration performance.

The invention discloses a preparation method of a high-temperature-resistant benzidine yellow pigment, and belongs to the technical field of pigment synthesis, and the high-temperature-resistant benzidine yellow pigment is prepared by diazotizing 3, 3 '-dichlorobenzidine, coupling the diazotized 3, 3'-dichlorobenzidine with a sulfonimide modified acetoacetanilide derivative to obtain a pigment compound, and finally compounding the obtained pigment compound with sulfanilamide group grafted polyethersulfone. According to the high-temperature-resistant benzidine yellow pigment prepared by the preparation method disclosed by the invention, the high-temperature-resistant performance of the benzidine yellow pigment is remarkably improved and the use performance of the benzidine yellow pigment is improved by introducing the sulfonimide group and the polyethersulfone grafted with the sulfanilamide group for synergistic modification.

The invention belongs to the technical field of sensors, and relates to an array sensor based on cerium-based metal organic framework nano-enzyme and detection application of perfluoroalkyl compounds. The array sensor is a Ce-MOF triple enzyme activity array sensor and is provided with a plurality of mutually independent sensing channels; the sensing channel contains a Ce-MOF nano enzyme and a chromogenic substrate; the chromogenic substrates comprise a first chromogenic substrate, a second chromogenic substrate and a third chromogenic substrate, the first chromogenic substrate comprises 3, 3 ', 5, 5'-tetramethyl benzidine, the second chromogenic substrate comprises 2, 4-diaminophenol and 4-aminoantipyrine, and the third chromogenic substrate comprises xanthine, purine oxidase and nitrogen blue tetrazole. The MOF nano-enzyme array sensor constructed by the invention has relatively high sensitivity and selectivity in identification and distinguishing of PFASs compounds, not only can accurately distinguish single PFASs compounds, but also can perform quantitative detection, and has good response to PFASs with different concentrations.

The invention discloses a preparation method of photoresponse COFs coated CeO2 nano-enzyme, and relates to the field of nano-materials. According to the invention, FePc, TAPP and 2, 5-dihydroxy-1, 4-phthalaldehyde are used for creating a core-shell material CeO2 (at) FePC / por-COF of photoresponse peroxidase based on COFs (Covalent Organic Frameworks), and the core-shell material CeO2 (at) FePC / por-COF is used for preparing the photoresponse peroxidase based on COFs. According to the invention, the highly ordered structural characteristic of the COFs material is utilized, so that the problem of fluorescence quenching caused by aggregation of traditional micromolecule photosensitizers (such as porphyrin, phthalocyanine and the like) in the use process is effectively solved. According to the present invention, the photoresponsive peroxidase activity is significant, and the chromogenic substrate of tetramethyl benzidine (TMB) can be effectively catalyzed; fePc is integrated into a COFs structure, so that the photoresponse activity of the COFs under near-infrared 808 nm is enhanced, and the COFs have excellent reactive oxygen species (ROS) generation capacity, and have great potential in the aspects of photodynamic therapy, antibacterial treatment, cell imaging and the like in biomedical application.

The invention provides high-permeability colorimetric hydrogel for detecting the content of glucose in sweat and a preparation method of the high-permeability colorimetric hydrogel, and relates to the technical field of wearable colorimetric sensing. The preparation method of the high-permeability colorimetric hydrogel comprises the following steps: mixing polyoxyethylene polyoxypropylene ether, chloroplatinic acid, chloroauric acid and water, and then adding L-ascorbic acid for reaction to obtain gold-platinum nanocrystalline dendrites; the preparation method comprises the following steps: mixing polyvinyl alcohol, 3, 3 ', 5, 5'-tetramethyl benzidine, gold-platinum nanocrystalline dendrites, ethylene glycol and water to obtain a hydrogel precursor solution, and curing the hydrogel precursor solution to obtain a hydrogel precursor; and soaking the hydrogel precursor in a sodium chloride solution to obtain the high-permeability colorimetric hydrogel for detecting the content of glucose in sweat. The gold-platinum nanocrystal dendrite nanoenzyme has tandem bio-enzyme activity, glucose oxidase activity and peroxidase double-enzyme activity, and TMB is used as a chromogenic substrate to prepare the hydrogel, so that colorimetric detection of glucose can be realized.

The invention discloses a nano-enzyme-SERS (Surface Enhanced Raman Scattering) bifunctional sensor for detecting colorectal cancer markers with high sensitivity as well as a preparation method and application of the nano-enzyme-SERS bifunctional sensor. The preparation method comprises the following steps: coating a layer of platinum (Pt) on the surface of gold nanoparticles (AuNPs) by utilizing a chemical reduction method so as to form gold-platinum nanoparticles (Au (at) Pt NPs); assembling the synthesized Au (at) Pt NPs into an aminated capillary tube through electrostatic adsorption, so as to prepare a capillary tube SERS (Surface Enhanced Raman Scattering) substrate; the surface of Au (at) Pt NPs is modified with a marker aptamer through an Au-S bond, and the nano enzyme-SERS dual-function sensor is prepared. In the presence of hydrogen peroxide (H2O2), the Au (at) Pt NPs can catalyze the oxidation of 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) to generate oxidized TMB (oxTMB) with a strong SERS (Surface Enhanced Raman Scattering) signal. When Hcy exists, the reductive sulfydryl of Hcy consumes hydroxyl free radicals (. OH) generated by H2O2 decomposition, so that TMB oxidation is inhibited, and SERS signal intensity is weakened. A linear regression equation of the logarithm of the Hcy concentration and the signal intensity is drawn according to the SERS signal intensity, so that quantitative detection of the Hcy is realized.

The invention relates to the technical field of waste water neutralization, in particular to a method for preparing 3, 4-difluorobenzene. The invention discloses a 3, 3 '-dichlorobenzidine hydrochloride neutralization wastewater treatment system and method, the system comprises a neutralization tank, a stirring unit, a discharge pipe, a PH value sensor, a liquid level sensor and a cleaning assembly, the cleaning assembly comprises two filter plates, a circulating pump, a transfer unit and a plurality of first nozzles, liquid is discharged out of the neutralization tank, and precipitates, impurities or suspended solids are filtered through the filter plates; filtrate is conveyed to the transfer unit through a circulating pump; the filtrate is sprayed out from a plurality of first spray heads and uniformly flushes off sediments, impurities or suspended matters attached to the interior of the neutralization tank; according to the utility model, the waste liquid after neutralization is discharged and filtered, and then the filtered filtrate flows back into the neutralization tank to wash attached sediments, impurities or suspended matters, so that the internal sediments, impurities or suspended matters are cleaned through repeated circulating filtration, and the quality of subsequent catalytic oxidation is greatly improved.

The invention discloses a machine learning enhanced silver-based covalent organic framework nano-enzyme colorimetric detection method and application thereof, and constructs a nano-enzyme which is formed by loading silver nanoparticles on a covalent organic framework and has oxide-like enzyme activity, and the nano-enzyme is used for rapid visual detection of mercury ions. When mercury ions exist, silver ions in the COF-AgNPs can form silver amalgam with the mercury ions, so that a colorless substrate 3, 3 ', 5, 5'-tetramethyl benzidine is catalyzed to generate a blue oxidation product oxTMB. And the mercury content can be judged by detecting the absorbance and RGB value change of the chromogenic reaction. And meanwhile, a machine learning data analysis strategy of a support vector machine model is adopted to carry out five-fold layered cross validation analysis on the obtained absorbance value and RGB value, so that the detection range is expanded, and the detection sensitivity is improved.

The invention belongs to the technical field of tin ion detection, and provides a method for detecting tin ions based on Ce-UiO-66-NO2 nano enzyme. The method comprises the following steps: mixing Ce-UiO-66-NO2 nano-enzyme with colorless 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) to generate blue oxidation-state TMB, then adding a sample containing tin ions (Sn < 2 + >), and reducing the oxidation-state TMB by utilizing the strong reducibility of the tin ions (Sn < 2 + >), so that the color of the solution becomes light; the tin ions (Sn < 2 + >) are qualitatively detected according to color change, or the tin ions (Sn < 2 + >) are quantitatively detected by utilizing a linear relation between the change of the absorbance value of the solution before and after the tin ions (Sn < 2 + >) are added and the concentration of the tin ions (Sn < 2 + >). The method has the advantages of low detection limit, high selectivity and good stability, and realizes the purpose of rapid detection of tin ions in tap water.

The invention relates to the technical field of analytical chemistry and food pharmacy detection, in particular to a rutin antioxidant activity colorimetric determination method based on a composite nano enzyme, which comprises the following steps: mixing a to-be-detected sample solution with an ABTS free radical cation working solution to carry out first reaction, so that an antioxidant substance in a sample and ABTS free radical cations are subjected to scavenging reaction; adding the composite nano enzyme, a 3, 3 ', 5, 5'-tetramethyl benzidine solution and a hydrogen peroxide solution into a system after the first reaction is completed, and initiating a second reaction; and measuring the absorbance value of the system after the second reaction under a specific wavelength, comparing the absorbance value with the standard curve obtained through the treatment in the same step, and calculating the antioxidant activity expressed by the equivalent concentration of rutin in the sample to be detected. By optimizing reaction conditions, the method provided by the invention simplifies operation steps and can provide accurate measurement results in a wider concentration range.

The invention belongs to the technical field of energy storage, and discloses a covalent organic framework film with a sandwich structure as well as a preparation method and application of the covalent organic framework film. The preparation method comprises the following steps: carrying out condensation reaction on 2, 2 '-benzidine disulfonic acid and trialdehyde phloroglucinol to prepare a self-supporting covalent organic framework membrane, dip-coating the self-supporting covalent organic framework membrane in a polybenzimidazole solution, and carrying out phase inversion to prepare the covalent organic framework membrane with a sandwich structure. According to the invention, selective transfer of protons is realized by using a pore structure and a sulfonic acid group in the covalent organic framework, vanadium ion permeation is hindered, and meanwhile, in the battery assembly and operation process, the polybenzimidazole layers on the two sides play a role in protecting the covalent organic framework membrane. The prepared membrane has high proton selectivity and battery efficiency.

The invention provides a high-entropy nano enzyme. The chemical formula of the high-entropy nano enzyme is Mn < 0.4 > Co < 0.4 > Ni < 0.4 > Cu < 0.4 > Zn < 0.4 > Fe < 2.0 >) O. The invention also provides a preparation method of the high-entropy nano-enzyme, which comprises the following steps: dissolving manganese nitrate tetrahydrate, cobalt nitrate hexahydrate, nickel nitrate hexahydrate, copper nitrate trihydrate, zinc nitrate hexahydrate and sodium citrate in deionized water to prepare a clear solution A; dissolving potassium ferricyanide in deionized water to prepare a clear solution B; directly pouring the solution B into the solution A, stirring, standing and aging the obtained mixed solution at room temperature, and centrifugally collecting a product; and calcining the sample powder in a muffle furnace to obtain the high-entropy nano-enzyme. The invention further provides a catalyst which is composed of the high-entropy nano enzyme, 3, 3 ', 5, 5'-tetramethyl benzidine and H2O2. The invention also provides a method for detecting reduced glutathione by using the microfluidic paper chip analysis device. The invention provides a new normal form for constructing a multifunctional biosensing and environment monitoring platform.

The present invention aims to provide polyimides and molded articles such as films that are environmentally safe, soluble in organic solvents, and have excellent transparency. [Solution] The above problem can be solved by a polyimide having a tetracarboxylic dianhydride component and a diamine component, wherein the diamine component includes a fluorine atom-containing diamine having a CF3-O- structure selected from 2,2'-bis(trifluoromethoxy)benzidine, 3,3'-bis(trifluoromethoxy)benzidine, and / or 2,3'-bis(trifluoromethoxy)benzidine, and the tetracarboxylic dianhydride component includes a tetracarboxylic dianhydride having a fluorene structure and an alicyclic tetracarboxylic dianhydride.

The invention relates to a down feather heat preservation finishing agent and a preparation method thereof, and belongs to the field of down feather finishing agents, the down feather heat preservation finishing agent is prepared from the following raw materials: a cyclodextrin derivative, functional powder, 2, 2 '-disulfonic acid benzidine and deionized water, the cyclodextrin derivative is obtained by sequentially mixing dimethyl sulfoxide, a ginkgo leaf fermentation product, pullulanase and ethanol into beta-cyclodextrin, then carrying out centrifugal treatment to obtain a precipitate, and finally drying the precipitate. A cyclodextrin derivative contained in the down feather heat-preservation finishing agent is beta-cyclodextrin modified by ginkgo leaf leavening, and the down feather heat-preservation finishing agent further comprises functional powder which is obtained by taking a zirconium diboride precursor solution as a raw material, mixing with mint essential oil and matching with a high-temperature calcination means, so that after the down feather heat-preservation finishing agent is applied to down feather, the heat preservation effect of the down feather is improved; the heat preservation performance of the down feather can be enhanced, and the heat preservation performance of the down feather can be stably maintained for a long time.

The invention discloses a method for preparing high-purity 3,3'-diaminobenzidine by a two-step temperature increase method, which relates to the technical field of preparation of benzidine compounds. The preparation steps are: two-step temperature increase reaction: 3,3'-dichlorobenzidine hydrochloride, copper salt, water and liquid ammonia are added sequentially in a stainless steel autoclave, and a two-step temperature increase reaction is performed; filtration crystallization: filtering to obtain a dark brown ammoniate, hot melting, hot filtering, cooling crystallization to obtain a crude product; purification: the crude product is added with water, activated carbon and ammonium thiohydrochloride, fully dissolved and filtered, the filtrate is slowly cooled and crystallized to obtain a relatively pure product, and the purification step is repeated multiple times to obtain high-purity 3,3'-diaminobenzidine. The advantages of the present invention are: a two-stage temperature increase preparation method is adopted to reduce impurity generation and obtain a high-purity product; purification uses ammonium thiohydrochloride as an antioxidant to reduce the generation of oxidative impurities, improve purity, and purified wastewater can be applied, with good economy and environmental protection, and with a high yield.

The application discloses a preparation method of carbon dot nanometer enzyme, which comprises the following steps: dissolving oxalic acid, polyacetyl imine and ferric nitrate in ultrapure water, heating and mixing, cooling to room temperature, centrifuging, filtering, dialyzing and taking supernatant to obtain the carbon dot nanometer enzyme; and a double-mode detection method for colorimetric and fluorescent detection of glyphosate in fruits and vegetables is constructed by using the prepared oxalic acid carbon dot nanometer enzyme, acetylcholinesterase, acetylcholine, 3,3',5,5'-tetramethyl benzidine and H2O2. The oxalic acid carbon dot nanometer enzyme is prepared by doping ferric nitrate and tetraethylenepentamine with oxalic acid as a precursor, has excellent peroxidase-like activity, and a colorimetric and fluorescent double-mode detection method for glyphosate is constructed by using the oxalic acid carbon dot nanometer enzyme, the double-mode detection results can be verified with each other, and the accuracy and reliability of the detection results are significantly improved.

The invention relates to the field of high polymer materials, in particular to an oil-water-resistant polyimide resin insulating material and a preparation method thereof.The oil-water-resistant polyimide resin insulating material comprises a polyimide precursor, core-shell structure inorganic filler and a DMAc / NMP mixed solvent, and the polyimide precursor is prepared from ODA, BPDA, PMDA and 2, 3, 4-triazole. 2, 2-bis (trifluoromethyl) benzidine is prepared through segmented feeding and polymerization; the core-shell filler takes silicon dioxide as a core and is grafted with an amino silane and fluoroalkyl silane double-coupling layer. The preparation method comprises the steps of core-shell filler synthesis, staged polymerization, ultrasonic dispersion and three-stage gradient curing. The material forms a gradient cross-linked network with a compact surface and a loose interior, after the material is soaked in ATF oil containing 0.5% of water at 155 DEG C for 2000 h, the weight change rate is smaller than or equal to 1.2%, the insulation resistance retention rate is larger than 95%, and the material has excellent oil-water erosion resistance, insulativity and mechanical property and has wide application prospects.

The invention discloses a polyamide semi-solid electrolyte, which comprises polyamide, a lithium salt and an electrolyte, wherein the polyamide is obtained by polymerizing polybasic acyl halide, 4, 4 '-diamino-2, 2'-bis (trifluoromethoxy) benzidine and a diamine monomer 1; the diamine monomer 1 is at least one of amino-terminated polyethylene glycol and amino-terminated polysiloxane. The invention also discloses a preparation method of the polyamide semi-solid electrolyte, which comprises the following steps: carrying out polymerization reaction on 4 '-diamino-2, 2'-bis (trifluoromethoxy) benzidine, a diamine monomer 1 and polybasic acyl halide in an organic solvent, and adding proline to remove HCl so as to obtain a polyamide solution; then adding lithium salt into the polyamide solution, and uniformly mixing to prepare a thin film; and soaking or wetting the thin film with an electrolyte to obtain the polyamide semi-solid electrolyte with high lithium salt content. The invention also discloses an application of the polyamide semi-solid electrolyte. The fabric has high ionic conductivity.

The invention discloses a lactate oxidase portable mobile phone sensing method based on a composite MXene thin-layer material and an application of the lactate oxidase portable mobile phone sensing method. Firstly, a Cu0. 9Zn0. 1S (at) MXene thin-layer material is synthesized and can catalyze H2O2 into hydroxyl free radicals, the generated hydroxyl free radicals react with a colorless 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) solution to generate blue oxidation-state 3, 3 ', 5, 5'-tetramethyl benzidine (oxTMB), the oxTMB can have an obvious ultraviolet absorption peak at 652nm, and a novel visual analysis method is constructed by taking the peak as signal output; besides, lactate oxidase can catalyze lactic acid to generate pyruvic acid and H2O2, a new method is used for LA or LOX analysis by taking H2O2 as a relation, H2O2 generated by the reaction can participate in the oxidation reaction of TMB, an obvious ultraviolet absorption peak can appear at 652nm, and the inhibitor Fe (III) can inhibit the reaction. On the basis, a portable mobile phone sensing method which is rapid, simple and low in cost is constructed, and the method is successfully applied to sensitive detection of LOX in HEK293S cells and has scientific significance.

This invention discloses a method for preparing covalent organic framework microcapsules immobilized enzymes and their applications. Using sodium polystyrene sulfonate-doped calcium carbonate as a template, polyethyleneimine and enzyme molecules are sequentially adsorbed onto the calcium carbonate surface based on electrostatic interactions. Trialdehyde phloroglucinol and benzidine are simultaneously added to the calcium carbonate template with the adsorbed enzyme. Based on the enzyme-induced catalytic effect, covalent organic framework microcapsules are generated on the calcium carbonate surface. After post-treatment to remove the calcium carbonate template, the covalent organic framework microcapsule immobilized enzyme is finally obtained. When used for the conversion of pyruvate to lactate, the immobilized enzyme activity retains 70% of the free enzyme activity. After eight cycles, the immobilized enzyme activity still retains 89% of the initial activity, exhibiting high immobilized enzyme activity and stability. The preparation method is simple, environmentally friendly, and has significant application potential.

The invention discloses a preparation method of a pH-sensitive cationic covalent organic framework corrosion inhibitor as well as a product and application of the pH-sensitive cationic covalent organic framework corrosion inhibitor, and the preparation method comprises the following steps: mixing 1, 3, 5-tri (1h-imidazole-1-yl) benzene and 4-(bromomethyl) benzaldehyde, injecting N, N-dimethylformamide, magnetically stirring and heating; adding 3, 3 '-dihydroxybenzidine, dioxane, absolute methanol and water acetic acid, freezing, vacuumizing, and washing; and mixing with benzotriazole, dissolving, vacuumizing, centrifuging and filtering. The corrosion inhibitor is loaded into micropores of the two-dimensional layered pH-sensitive cationic covalent organic framework through physical and chemical adsorption, the corrosion inhibitor is prevented from being in direct contact with components such as water and cement in the concrete mixing stage, and a cationic carrier can adsorb corrosive ions such as chloride ions and carbonate ions in concrete through ion exchange; and the pH sensitive carrier shell releases the corrosion inhibitor by identifying a signal that the pH of the micro-area is reduced when the steel bar is corroded.

The invention provides a method for detecting the total antioxidant capacity of saliva based on iron-based MOF nano-enzyme, and belongs to the field of biosensing. The method comprises the following steps: obtaining an MIL-53Fe nano enzyme; the preparation method comprises the following steps: mixing a diluent of MIL-53Fe nano-enzyme, a sodium acetate buffer solution, 3, 3 ', 5, 5'-tetramethyl benzidine and hydrogen peroxide for reaction, adsorbing a reaction solution by using filter paper, drying and curing by using a chitosan solution to obtain the visual microfluidic detection paper-based chip. Establishing a standard curve of the chromatic value and the ascorbic acid concentration; dropwise adding the treated saliva sample onto the paper-based chip, standing for reaction to obtain a chromatic value, and calculating according to the standard curve to obtain the total antioxidant capacity value of the saliva. Complex matrix interference is broken through, the detection sensitivity and portability are improved, and therefore clinical application of saliva TAC detection in noninvasive health monitoring is promoted.

The invention discloses a pentagonal porphyrinyl covalent organic framework material as well as a preparation method and application thereof. According to the material, 5, 10, 15, 20-tetra (4-aminophenyl) nickel porphyrin and N, N '-bis (4-formylphenyl)-N, N'-diphenyl benzidine are used as construction units, and a two-dimensional covalent organic framework structure with pentagonal pore topological characteristics is formed through a Schiff base condensation reaction. Ni-N4 coordination structures which are uniformly distributed in the material construct catalytic sites similar to a natural enzyme active center in a non-uniform pore microenvironment, and the material shows excellent and stable peroxidase-like catalytic activity. The preparation method of the material has the advantages of clear process steps and mild reaction conditions, and is suitable for stable and repeated preparation. A catechol inhibition type colorimetric sensing system constructed on the basis of the material has good analysis performance in the aspects of detection linear range, detection limit and the like and does not need to depend on large-scale instruments and equipment, and a detection result can be observed through naked eyes.

This invention provides a diazobiphenyl dye for thin-film polarizers, which is an analog of AD1. Thin-film polarizers prepared using this dye exhibit good optical quality, such as low light scattering, high dichroism ratio, broadband absorption, and / or stability to heat and light irradiation. This invention also provides a method for preparing the diazobiphenyl dye from two different monoazo dyes via a cross-coupling reaction. This method is eco-friendly because it does not use toxic benzidine as a raw material. The product (diazobiphenyl dye) obtained by this method can be purified in a simple and convenient manner, and the diazobiphenyl dye prepared by this method can have a symmetrical or asymmetrical structure. Furthermore, this invention provides a thin-film polarizer comprising the diazobiphenyl dye and an apparatus for display applications comprising the thin-film polarizer.

The application discloses an electrochemical biosensor based on specific nucleic acid aptamer fragments and glucose oxidase. The specific recognition of the same target object by the double nucleic acid aptamer is utilized to combine the modified metal organic framework compound and the magnetic nanoparticles with the target object to form a self-assembly structure, and the magnetic nanoparticles are separated out by utilizing the magnetism of the magnetic nanoparticles. Meanwhile, the specific catalytic action of the glucose oxidase on glucose produces hydrogen peroxide to further oxidize 3,3'-diamino benzidine to generate an electrochemical signal, and the metal organic framework compound and the magnetic nanoparticles both have peroxidase-like activity, which can further synergistically catalyze the oxidation of 3,3'-diamino benzidine by hydrogen peroxide, and the sensitivity is improved. Thus, based on the linear relationship between different concentrations of pathogen solutions and corresponding electrochemical signal intensities, the electrochemical biosensor realizes high-sensitivity detection of the hyacinth yellow rot fungus.

The invention discloses a nanogold and wood composite material, a preparation method, application and a method for determining the content of glucose in reconstituted tobacco, glucose oxidation is directly catalyzed through the nanogold and wood composite material (AuNPs and wood), the glucose and tetramethyl benzidine (TMB) are subjected to a chromogenic reaction, and the content of the glucose in the reconstituted tobacco is determined by combining the linear relation between absorbance and the glucose concentration. And whether the glucose exists in the reconstituted tobacco and the concentrated solution sample or not and the specific content of the glucose can be accurately judged. The method provided by the invention can quickly obtain a detection result within 30 minutes, is suitable for efficiently screening reconstituted tobacco and concentrated solution samples with the glucose content lower than 0.01 gL <-1 >, can accurately determine the actual content of glucose in the reconstituted tobacco and the concentrated solution, does not need to depend on a standard substance or carry out modeling maintenance, and is simple and convenient to operate. The equipment cost is obviously reduced; and the operation process is simplified.

The invention discloses a colorimetric-fluorescence dual-mode detection method for salmonella and escherichia coli, and belongs to the technical field of biological detection. According to the invention, concanavalin A (ConA) is coupled with magnetic nanoparticles (MNPs) to form MNPs (at) ConA as a capture probe by recognizing the characteristic of capturing bacteria by sugar residues, and in addition, an antibody (Ab) can specifically recognize bacteria and is coupled with quantum dots (QDs) to form QDs (at) Ab as a fluorescence signal probe. The invention finds that MNPs can catalyze 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) to generate blue oxTMB which can be observed by naked eyes; and the QDs have strong fluorescence and can also be observed by naked eyes, so that obvious distinguishing is realized in Sal and Esc detection. And the signal is linearly related to the target bacteria, so that the visibility is good. The practicability of the method is verified by detecting milk tea, milk and fruit juice samples, and the recovery rate is 93.5-106%. The feasibility of detecting Sal and Esc by the method is verified, and the method has important application potential in food safety monitoring.

The present invention discloses a high-temperature resistant nanofiltration membrane based on a rigid amine monomer, its preparation method and application, belonging to the technical field of water treatment materials. The preparation method of the high-temperature resistant nanofiltration membrane includes: after an interfacial polymerization reaction occurs between a solution containing a rigid amine monomer and an oil-phase solution containing a polyvalent acyl chloride monomer on a porous support membrane, curing and crosslinking are carried out to prepare the high-temperature resistant nanofiltration membrane based on the rigid amine monomer; the rigid amine monomer is selected from 3,3'-dihydroxybenzidine, 3,3'-dimethylbenzidine, 3,3'-diaminobenzidine, 2,2'-benzidine disulfonic acid, etc. The introduction of the rigid amine monomer combined with the improvement of the process can effectively improve the temperature resistance of the polyamide separation layer. The method steps of the present invention are simple and efficient, and the prepared nanofiltration membrane has a high density and can be used to intercept the high-valence anion salts in high-temperature saline feed liquid, and has good application prospects in the treatment of high-temperature saline feed liquid.

The invention provides a silane coupling polymer membrane for H2 / CO2 separation as well as a preparation method and application of the silane coupling polymer membrane. Soaking the support body in a 1, 3-bis (3-aminopropyl)-1, 1, 3, 3-tetramethyldisiloxane aqueous solution, taking out the support body, and naturally airing the support body until no obvious liquid drops exist on the surface of the support body; soaking the support body in a mixed water phase solution containing 3, 3 '-diaminobenzidine and melamine, removing redundant water phase solution after a period of time, and naturally airing; then soaking in a mixed organic phase solution containing paraphthaloyl chloride and trimesoyl chloride, and carrying out interfacial polymerization reaction on amino and acyl chloride on the surface of the support body to generate an initial polymer membrane; and then putting into a drying oven for heat treatment to obtain the final silane coupled bibenzimidazole and amide connected polymer film. The H2 permeability of the membrane under the conditions of 200 DEG C and 1 bar is 225 GPU, and the H2 / CO2 selectivity is 101. The method is simple to operate and short in preparation period; the gas separation performance is excellent at high temperature and high pressure, and large-scale preparation is easy.