2631 results about "High selectivity" patented technology

An IPD high-selectivity band-pass filter based on a weak coupling transformer technology comprises an LC parallel resonance circuit, an LC series resonance circuit, an LC parallel resonance circuit and a fourth capacitor C4, and inductors in the LC parallel resonance circuit and inductors in the LC parallel resonance circuit have a weak transformer coupling relation; the coupling coefficient required by the weak coupling transformer provided by the invention is very small and can be realized in a mode of adjacently placing metals on the same layer, so that the structural complexity of the filter is effectively reduced; the band-pass filter is based on an IPD technology, an extra decoupling equivalent inductor is introduced through a weak transformer coupling technology, the extra decoupling equivalent inductor and a parallel capacitor which is connected between the input end and the output end of the filter in a bridging mode form a new resonance path, and a transmission zero point is introduced into an upper stop band and a lower stop band of the filter respectively to improve the selectivity of the filter. According to the invention, the selectivity of the filter can be effectively improved on the premise of not additionally introducing an inductance element and not increasing the order of the filter.

The invention discloses a method for extracting and purifying flavone in litsea coreana through an ultrasonic-assisted eutectic solvent, and belongs to the technical field of green processing of natural products. The invention provides a method for efficiently preparing litsea coreana flavone by integrating computer prediction, green solvent extraction and resin purification technologies. The method comprises the following steps: firstly, calculating and screening a deep eutectic solvent system with the highest affinity with the litsea coreana flavone on the basis of a COSMO-RS theoretical model, then coupling the optimized DES with an ultrasonic-assisted extraction (UAE) technology, and through the synergistic effect of the DES and the UAE technology, remarkably improving the extraction rate of the litsea coreana flavone and furthest keeping the biological activity of a target component; then, a macroporous resin dynamic adsorption-desorption purification process is linked, so that high-selectivity enrichment and impurity removal of the flavonoid compounds in the crude extract are realized, a high-purity product is obtained, and a complete process route from intelligent screening, efficient extraction to precise purification is finally formed.

The invention discloses an omariglitazone intermediate as well as a synthesis method and application thereof, and belongs to the technical field of pharmaceutical chemistry synthesis. The invention provides a synthesis method of an omarigliflozin intermediate and application of the intermediate in synthesis of omarigliflozin. The key of the synthesis method provided by the invention lies in the deprotection process of polycyclic indole amide, nitrile groups are not hydrolyzed, indole carboxylic acid is generated with high selectivity, molecular lactamization is avoided in the condensation process with polycyclic imine B, and expensive amidation reagents such as HATU are not needed in the process, so that the synthesis method is simple and easy to implement. And the purpose of preparing omariglitazone with low cost and high yield is achieved. The synthesis method has the advantages of easily available raw materials, mild reaction conditions, small side reaction influence, simplicity and convenience in operation and high yield, improves the yield, is easy to purify, and is suitable for industrial production of omariglitazone.

The invention relates to the technical field of analysis and detection, in particular to a fluorescent switch sensor based on quantum dot-nano porphyrin and application. The specific technical scheme is as follows: the fluorescent switch sensor is constructed by utilizing cadmium telluride quantum dots modified by mercaptosuccinic acid and a 5, 10, 15, 20-tetra (4-nitrophenyl) porphyrin nano material modified by a cationic surfactant hexadecyl trimethyl ammonium bromide. And the method has a good enrichment effect on zearalenone. The sensor has high sensitivity, high selectivity and anti-interference performance, can accurately analyze trace zearalenone in actual grain samples (corn, rice, soybean and the like), and has the advantages of simplicity in operation, low detection limit, high sensitivity, low cost and the like.

The invention relates to the technical field of fine chemical engineering and flame retardant preparation, and discloses a preparation method of bromo-triazine capable of improving thermal stability, and the preparation method comprises the following steps: mixing phenol, water and dichloromethane, controlling the temperature, and carrying out oxidative bromination reaction to prepare an organic phase containing tribromophenol; then, under the action of an organic amine catalyst, carrying out condensation reaction on the organic phase, liquid caustic soda and cyanuric chloride; after the reaction, washing with water to remove impurities; and in the presence of process water, firstly controlling the temperature at 38-42 DEG C for azeotropic desolvation, then raising the temperature to 85-95 DEG C for high-temperature crystallization and crystal growing, and finally cooling, filtering and drying to obtain the bromo-triazine product. By utilizing the high selectivity of the organic amine catalyst and a two-stage azeotropic crystallization process, the side reaction is effectively reduced, the solvent wrapped in the crystal is eliminated, the prepared product is high in main content and extremely low in volatile component, the temperature can reach 370 DEG C or above when the thermal weight loss is 2%, and the thermal stability is remarkably improved.

The invention relates to the technical field of analysis and detection, in particular to a surface enhanced Raman spectroscopy (SERS)-based nano material detection method, which is characterized in that a heterojunction composite structure consisting of noble metal nano stars and semiconductor oxide nano particles is used as an SERS active substrate; and a specific recognition molecule carrying a Raman reporter molecule is used as a detection probe. During detection, the recognition molecules are firstly combined with the to-be-detected nano material, and then the compound is adsorbed on the surface of the substrate. The tip structure of the noble metal nanostar and a heterojunction interface jointly generate a synergistic effect of electromagnetic enhancement and chemical enhancement, and a reporter molecule signal is doubly amplified, so that high-sensitivity and high-selectivity detection on a to-be-detected nano material is realized. The method solves the problems of weak signal and poor selectivity of the traditional method, and is suitable for rapid and quantitative analysis of trace nano materials in the environment.

The invention discloses an organelle-targeted fluorescent probe for specific detection of tumor cells as well as preparation and application of the organelle-targeted fluorescent probe, and the specific structural formula of the fluorescent probe is as follows: BCY-DP shows obvious specific targeting ability of tumor cell mitochondria and has been applied to ONOO-selective imaging in living cell mitochondria; results show that the BCY-DP has high selectivity on ONOO <-> in tumor cells, can successfully distinguish the ovarian cancer cells from normal ovarian cells, and can be used for diagnosis of cancer cells.

The invention relates to the field of sensors, and discloses a solid electrolyte for ammonia gas detection, an electrochemical luminescence sensor, a preparation method and a detection method, and the solid electrolyte for ammonia gas detection comprises the following raw materials: a second electrolyte, a luminescent substance, an optional first electrolyte and an optional binder. The solid electrolyte for ammonia gas detection provided by the invention can realize ppb-level NH3 selective detection with high sensitivity, wide linear response range and low detection limit at room temperature for an electrochemical luminescence sensor for detecting ammonia gas. The electrochemical luminescence sensor for detecting the ammonia gas can be used for sensing the ammonia gas through a cyclic voltammetry method and a constant potential-luminescence technology, and ppb-level high-sensitivity and high-selectivity ammonia gas detection is realized.

The invention provides a cation exchange membrane chromatography medium and a preparation method and application thereof, the cation exchange membrane chromatography medium comprises a homo-porous membrane, polydopamine is loaded on two side surfaces and in a pore structure of the homo-porous membrane, and a cation exchange functional ligand is grafted on the polydopamine; a homogeneous pore membrane is selected as a matrix membrane, polydopamine is loaded on the surface and in an internal pore structure of the homogeneous pore membrane, and then a cation exchange functional ligand is further grafted, so that the surface of a chromatography medium of the obtained cation exchange membrane has relatively strong negative charges, and biomolecules with positive charges can be effectively adsorbed, thereby being separated from biomolecules with negative charges; meanwhile, the membrane is relatively low in transmembrane pressure and relatively high in separation degree, also has the characteristics of high permeability and high selectivity, and is suitable for being applied to separation and purification of biological drug macromolecules.

The invention discloses an internal-acid and external-alkali type organic-inorganic hybrid molecular sieve catalyst as well as a preparation method and application thereof, and belongs to the technical field of heterogeneous catalytic materials and chemical processes. According to the catalyst, a hydrogen type Beta molecular sieve is used as an acidic inner core, polyvinylpyrrolidone (PVP) is used as an organic shell, and a unique inner-acid outer-alkali structure is formed. The preparation method comprises the following steps: hydrothermally synthesizing a hydrogen type Beta molecular sieve with a specific silica-alumina ratio, and then coating PVP through surface adsorption. The catalyst is used for catalyzing the condensation of methylal and trioxymethylene under mild conditions (40-70 DEG C and normal pressure) to prepare polyoxymethylene dimethyl ethers (DMMn). The PVP shell covers acidic sites on the outer surface of the molecular sieve to form an external neutral / weak base and internal strong acid microenvironment, so that the secondary side reaction of the product is effectively inhibited, the trioxymethylene conversion rate of more than 98% and the DMMn selectivity of more than 96% can be obtained in the reaction at 50 DEG C and normal pressure, the product distribution can be regulated and controlled, and the traditional Anderson-Schulz-Flory distribution limitation is broken through. The catalyst disclosed by the invention has the advantages of high activity, high selectivity, mild conditions and easiness in separation, and has a good industrial application prospect.

The invention belongs to the field of methanol conversion and utilization, and particularly relates to a three-layer multi-core structure catalyst for high-selectivity synthesis of monomethylamine and a preparation method of the three-layer multi-core structure catalyst. The core layer of the catalyst is gamma-aluminum oxide, the middle layer of the catalyst is a mordenite (MOR) molecular sieve, and the outer layer of the catalyst is porous SiO2. The preparation of the multi-core MOR layer adopts a steam-assisted crystallization method, the preparation method is simple, no organic waste liquid is generated, the preparation method is environment-friendly, the multi-core MOR layer can be used in a reaction for preparing methylamine through continuous gas phase catalytic amination of methanol after being modified by ammonium ion exchange and chemical liquid phase deposition (CLD), the methanol conversion rate reaches 98.6% under the reaction conditions that the temperature is 340 DEG C, the methanol liquid hourly space velocity is 1.5 h <-1 >, the ammonia-alcohol ratio is 3 and the pressure is normal, and the method is suitable for industrial production. The mass ratio of monomethylamine is greater than 60%, and the method has a good application prospect.

The invention discloses a double-morphology boron-containing Zn / Cu metal organic framework composite material as well as preparation and application thereof, and belongs to the technical field of fine chemical engineering. The double-morphology boron-containing Zn / Cu metal organic framework composite material is prepared through a one-pot hydrothermal reaction, and the double morphology comprises a three-dimensional nanoflower structure and a three-dimensional rod / columnar structure. Specifically, by adjusting the molar ratio of Zn to Cu in the coordination process with corresponding ligands, when the molar ratio of Zn to Cu reaches 1: 1, the original single nanoflower structure can generate a new three-dimensional rod / columnar structure, so that two composite forms are formed. The double-morphology boron-containing Zn / Cu metal organic framework composite material shows high activity and high selectivity when being used for two key reactions of electrochemical hydrogenation reduction and electrochemical oxidation of furfural.

The invention discloses a mercury ion detection fluorescent probe based on quinoline as well as a preparation method and application of the mercury ion detection fluorescent probe. The fluorescent probe and a structural formula of the fluorescent probe are shown as a formula I in the specification. A quinoline derivative, namely 2-methyl-7-hydroxyquinoline, is used as a fluorescent chromophore, a thioester group is used as a recognition group, and the prepared fluorescent probe shows high sensitivity and high selectivity on Hg < 2 + > in a solution. The preparation method of the fluorescent probe is simple in steps, raw materials are easy to obtain, and the obtained product is a white flocculent solid, is easy to store, has a wide application prospect and can be produced and applied on a large scale.

The invention discloses a zinc-sulfur co-doped ZIF-67 derivative composite material as well as a preparation method and application thereof, and belongs to the technical field of advanced oxidation. The composite material is prepared through a coordination-substitution-calcination integrated process. The preparation method comprises the following steps: firstly, mixing a cobalt source and an organic ligand in methanol, and introducing a sulfur source to form a cobalt-based precursor; and drying, grinding with a zinc source, and calcining in an inert atmosphere. According to the method, stable cobalt active sites are replaced by isocrystals of zinc, sulfur doping promotes cobalt and peroxymonosulfate to form a weak oxidizing intermediate, and efficient and high-selectivity degradation of organic pollutants is achieved under the condition that a strong free radical path is not needed. The material is stable in structure and high in water quality interference resistance, is suitable for catalyzing peroxymonosulfate to degrade organic pollutants in a water body, and particularly has remarkable advantages in a complex water body.

The invention provides a dye / ion separation membrane with pore diameter and charge coordinated regulation and control as well as a preparation method and application thereof, and belongs to the field of preparation of a double-layer ionic covalent organic framework (COFs) composite membrane. An aromatic polyamide ultrafiltration membrane is used as a base membrane, and a double-layer COFs membrane is constructed on the surface of the aromatic polyamide ultrafiltration membrane through a multi-time interfacial polymerization method. The first layer is a positive charge COFs layer formed by reacting a guanidyl monomer with 1, 3, 5-triformyl phloroglucinol (Tp); and the second layer is a negative charge COFs layer formed by reacting ionic aromatic diamine with Tp. By adjusting the type and concentration of the monomers, the pore diameter and charge distribution of the film layer can be synergistically regulated and controlled, and the double-layer composite film which is stable in structure and orderly stacked is constructed. The obtained membrane has molecular sieve separation and electrostatic regulation functions, can efficiently intercept organic dye molecules in high-salt printing and dyeing wastewater, and has high flux, high selectivity and good chemical stability.

The invention discloses a normal-temperature and normal-pressure optical fiber chemical synthesis method and device. The core is a sandwich type optical fiber chemical membrane electrode (anode / ion exchange membrane / cathode + diffusion layer); the parallel scattering type optical fiber realizes near-uniform illumination and local enhancement on an interface. The anode uses 90-112 nm VUV to promote H dissociation, and the cathode uses 80-100 nm VUV to activate and reduce N; the direct current / pulse of the power supply is programmable. The membrane is PEM / AEM / CEM (5-200m), and an ion channel is functionally optimized through nanofiller, crosslinking and functionalization; and the catalytic surface is loaded with 1-100nm of transition metal compound and anchored. Arranging an inert / reduced-pressure sealed light path to improve VUV coupling; raw material gas H: N = 1: 1-5 (preferably 1: 3), and inert carrier gas can be added. The system is connected to online characterization and AI closed loop, ammonia is continuously produced at 0-40 DEG C and 0.8-1.2 atm, and selectivity and Faraday efficiency are improved.

The invention belongs to the technical field of material chemistry, and particularly relates to a method for synthesizing an amide hydrogen bond organic framework material based on a one-pot method and gold recovery application. The preparation method comprises the following steps: dissolving a dihydroxybenzidine monomer in a formic acid monomer under 15-minute ultrasonic treatment, then adding ethylene glycol, and then carrying out ultrasonic treatment on the mixture for 5 minutes; then placing the sample bottle in a drying oven at 30 DEG C for constant-temperature evaporation so as to separate out brown blocky crystals; and filtering and collecting crystals, washing with water for multiple times, and carrying out vacuum drying at 60 DEG C to obtain the final material HOF-D. The HOF-D synthesized by the method disclosed by the invention can be used for rapidly recovering Au (III) from an aqueous solution with high selectivity, cycling stability and large capacity (5186 + / -10 mg. G <-1 >), so that the efficient adsorption and recovery of Au (III) in electronic waste liquid are realized, and the HOF-D has a good application prospect.

The present application relates to a kind of phosphine oxy group covalent modification composite adsorption material and its preparation method and purposes, the preparation method includes the following steps: (1) mixing dopamine hydrochloride, phosphine-containing substrate, tris-hydroxymethyl aminomethane hydrochloride and sodium hydroxide in solvent, to obtain mixed solution;(2) the mixed solution obtained in step (1) and solid phase material are mixed, then oscillation reaction is carried out, to obtain solid-liquid mixture;(3) the solid-liquid mixture obtained in step (2) is carried out solid-liquid separation, and the solid phase part obtained is sequentially washed and dried, to obtain phosphine oxy group covalent modification composite adsorption material.The phosphine oxy group covalent modification composite adsorption material provided by the present application has excellent adsorption selectivity and material stability, and can be used for the high-selectivity separation and recovery of rare metals indium and gallium.

The invention relates to an anti-interference high-selectivity omnidirectional planar filtering antenna, a filtering processing method and application, and the planar filtering antenna comprises a metal radiation layer, a first dielectric substrate, a first coupling layer, a second dielectric substrate and a second coupling layer which are sequentially stacked. The second dielectric substrate is provided with a plurality of metalized through holes which are distributed in an annular array mode and define a substrate integrated cavity with the first coupling layer and the second coupling layer, the metalized through holes divide the second coupling layer into an inner side patch and an outer side ring piece, and the inner side patch is evenly provided with a plurality of resonance grooves; and a feed probe penetrating and extending to the second dielectric substrate is arranged at the center of the bottom of the metal radiation layer. According to the invention, the substrate integrated waveguide technology is adopted, the substrate integrated cavity is formed, and a high-selectivity filtering effect is realized by utilizing the characteristic of high Q value, so that the interference of out-of-band signals is effectively inhibited, and the advantages of the patch antenna and the substrate integrated cavity are effectively combined.

Disclosed is a method of forming gate structures for n-type and p-type transistors. The method includes: forming an interfacial layer and high-K (HK) dielectric layer for the gate structures; forming an n-type metal layer over the HK dielectric layer; forming a hard capping layer over the n-type metal layer while simultaneously strengthening the HK dielectric layer by fluorine passivation; patterning photo resist (PR) material over the hard capping layer that exposes a portion of the hard capping layer over the p-type transistor; removing the n-type metal layer and the hard capping layer over the p-type transistor via wet etching operations using high selectivity chemicals that are highly selective to the hard capping layer and the n-type metal layer; removing the patterned PR material while insulating, by the hard capping layer, gate structures from aluminum oxidation; and forming a p-type metal layer over the hard capping layer and the p-type transistor.

The invention belongs to the technical field of inorganic chemical material preparation, and discloses a high-selectivity crystallization and impurity migration inhibition method of high-purity magnesium hydroxide. The method comprises the following steps: a phenylphosphonic acid surface modifier is introduced in the initial stage of crystallization, molecules of the phenylphosphonic acid surface modifier selectively occupy high-activity Mg < 2 + > sites of a magnesium hydroxide crystal face through bidentate coordination, and a molecular-level interface barrier with steric hindrance and electrostatic repulsion effects is formed, so that a Ca < 2 + > migration path is specifically blocked, and Mg < 2 + > crystallization is not influenced. The preparation method of the high-purity magnesium hydroxide is high in selectivity, high in efficiency, low in cost and environmentally friendly, the interface adsorption behavior of calcium ions is accurately intervened in the initial stage of crystallization through a molecular level surface engineering means, the technical bottleneck that impurity migration and lattice doping are difficult to control in a traditional process is fundamentally solved, and the preparation method is suitable for industrial production. And a brand new technical path is provided for green manufacturing of high-performance inorganic functional materials.

The invention discloses a high-dispersion and small-particle-size alpha-MoC1-x / SiO2 catalyst as well as a preparation method and application thereof. The catalyst is composed of alpha-MoC1-x nanoparticles dispersed on a silicon dioxide carrier, the alpha-MoC1-x / SiO2 catalyst is generated in a three-dimensional SiO2 confined network in a limited manner, wherein the three-dimensional SiO2 confined network is constructed by in-situ polycondensation of silica sol under the condition that the pH value is 2.3-2.8, and the molybdenum content is 30-60%; the average particle size of the alpha-MoC < 1-x > nanoparticles is 1.0-2.2 nm, and the alpha-MoC < 1-x > nanoparticles are highly dispersed in the SiO2 confinement structure; the alpha-MoC1-x nano-particles are face-centered cubic phase molybdenum carbide, and the mass fraction of the face-centered cubic phase molybdenum carbide is larger than or equal to 90 wt%. The alpha-MoC1-x / SiO2 obtained by the invention can realize higher methanol selectivity and intrinsic activity under the condition of 140-180 DEG C, and can stably operate for 100 hours. The invention provides a novel small-particle-size and high-dispersion molybdenum carbide catalytic material and a preparation strategy thereof for preparing methanol through low-temperature and high-selectivity CO2 hydrogenation.

The invention discloses a primary separation method and system of a liquid chromatography system.The method comprises the steps that a sample is pretreated according to physicochemical properties of a target sample, and a high-purity enriched sample is obtained; optimizing the composition proportion of the mobile phase according to the composition characteristics of the high-purity enriched sample to obtain the optimized mobile phase composition; selecting an optimal chromatographic column type according to the optimized mobile phase composition, and carrying out dynamic temperature control separation through a dynamic temperature control technology to obtain a high-selectivity separation condition; performing real-time detection on the separated chromatographic peak according to a high-selectivity separation condition to obtain a high-signal-to-noise-ratio detection signal; and evaluating the preliminary separation effect according to the high signal-to-noise ratio detection signal. By utilizing the embodiment of the invention, the enrichment efficiency and the separation selectivity of the sample can be improved, and the accuracy and the reliability of integral separation are further improved.

The invention discloses a method for deeply separating and extracting gallium, and belongs to the technical field of non-ferrous metallurgy. According to the method for deeply separating and extracting gallium, the problems that an existing adsorption material is generally poor in chemical stability, insufficient in selectivity and adsorption capacity and the like in a gallium-containing solution with high alkalinity and coexistence of multiple components are solved, and the gallium is deeply separated and extracted on the basis of the coordination characteristic of gallate ions. A covalent organic framework adsorption material with a directional recognition site and an ordered pore channel structure is designed and constructed. According to the material, an organic porous framework with high crystallinity and large specific surface area is constructed through dynamic covalent chemistry, and efficient and high-selectivity adsorption of gallate ions can be realized. The method is suitable for efficiently capturing and enriching gallium from a high-alkalinity complex solution, and a reliable technical solution with application prospects is provided for efficient recycling of gallium resources.

Provided is a method that allows for the etching of a silicon nitride film with respect to a silicon oxide film with high selectivity and high precision while preventing a degradation in the shape of the silicon oxide film portion during etching. The etching method of dry etching a film structure which is formed in advance on a wafer disposed in a processing chamber and in which an end portion of a film stack including a silicon nitride film and silicon oxide films vertically sandwiching the silicon nitride film forms a sidewall of a trench or hole, by supplying a gas for processing into the processing chamber, without using plasma includes: forming, as a first process, a reaction layer on the silicon nitride film by reaction of hydrogen fluoride gas at 30° C. or higher and 55° C. or lower; removing, thereafter, as a second process, the reaction layer having been formed in the first process, through volatilization by performing heating at 70° C. or higher and 110° C. or lower without causing the hydrogen fluoride gas to flow; and etching the silicon nitride film from the end portion in a lateral direction by performing the first and second processes a plurality of times.

The invention discloses a Pd-SnO2-SiO2 self-supporting flexible nanofiber membrane gas sensor for hydrogen detection and a preparation method of the Pd-SnO2-SiO2 self-supporting flexible nanofiber membrane gas sensor, and aims to solve the problems that an existing flexible gas sensor depends on an organic substrate and is poor in high temperature resistance and insufficient in room temperature performance. According to the sensor, an electrostatic spinning technology is adopted for preparing a double-phase nanofiber membrane with crystalline phase SnO2 as a framework and amorphous phase SiO2 as a filling agent, and self-supporting can be achieved without a flexible substrate; pd nanoparticles are deposited on the fiber membrane through magnetron sputtering, and an Ag interdigital electrode is printed. Wherein the crystal-amorphous double-phase structure not only endows the material with excellent flexibility and high air permeability, but also provides a rich gas reaction interface; due to the full-inorganic characteristic, the high-temperature-resistant performance is achieved. The sensor shows high sensitivity, high selectivity and good flexible stability to hydrogen at room temperature under the environment of 37 DEG C and 80% humidity, is suitable for detecting hydrogen exhaled by a human body through wearable equipment such as a mask, and provides a new scheme for the metal oxide flexible gas sensor.

The application discloses a lithium mica floating agent, a preparation method thereof and a lithium mica floating method. The lithium mica floating agent has a formula mass ratio of amine 8-35%, ether 10-40%, sodium dodecyl sulfate 8-35%, sodium sulfonate 5-30%, alcohol 10-35% and inorganic alkali 2-15%. The lithium mica floating agent can greatly improve the recovery rate of lithium metal, has very high selectivity to lithium mica, has high floating yield, good purity of the extract and low cost.

The invention relates to the technical field of gas adsorbents, in particular to an MOF-based gas adsorbent with a core-shell-shell structure as well as a preparation method and application of the MOF-based gas adsorbent. According to the MOF-based gas adsorbent disclosed by the invention, UiO-66 regulated and controlled by defect engineering is taken as a core layer, and the defect density in a UiO-66 crystal structure is accurately controlled by introducing a specific regulator glacial acetic acid, so that a sufficient physical adsorption space is provided for toluene molecules, and abundant acidic adsorption sites are formed; the PDA middle layer has dual functions of interface bonding and performance collaboration, so that the adsorption affinity of the material to toluene is further enhanced, and the adsorption performance is synergistically improved; the super-hydrophobic ZIF-8 is used as the outermost shell layer, on one hand, the super-hydrophobic ZIF-8 can be used as a molecular barrier to efficiently block external water molecules from entering the core layer UiO-66, the inactivation of core Zr active sites due to hydration is avoided, and the stability problem in a high-humidity environment is solved; and secondly, the diffusion behavior of toluene molecules can be regulated and controlled through a molecular sieving effect, so that high-selectivity and high-stability adsorption on toluene under a high-humidity condition is realized.

The invention provides a broadband absorption and transmission integrated frequency selective surface with a high selection characteristic, which comprises a first loss layer, a second loss layer and a frequency selection layer, and is characterized in that the first loss layer and the second loss layer realize a transmission band with the high selection characteristic and the broadband characteristic at the same time by using dual-order resonance; the second loss layer and the frequency selection layer are cascaded to realize the absorption and transmission integrated characteristic, and the first loss layer is used for improving the low-frequency and high-frequency wave absorption characteristics and expanding the wave absorption bandwidth. Under the combined action of the first loss layer, the second loss layer and the frequency selection layer, wave transmission within the frequency band of 7.72-11.89 GHz and wave absorption within the frequency band of 1.96-7.12 GHz and the frequency band of 12.95-17.33 GHz are achieved. The antenna has high selection characteristics and broadband characteristics, can effectively suppress interference of external electromagnetic waves of other frequency bands or electromagnetic waves of a frequency band close to a communication frequency band on communication, can reduce the radar cross section of a target, and facilitates target stealth.

The invention provides a preparation method and application of a high-sensitivity imprinted membrane for selectively detecting microcystic toxins (MC-LR) in water based on surface enhanced Raman scattering. The preparation method comprises the following steps: step 1, preparation of silver nanocubes; step 2, preparation of Ag NCs-coated TiO2 nanoparticles; step 3, preparation of an Ag NCs-coated TiO2 / PDMS composite membrane; according to the invention, a membrane technology, an SERS technology and MIT are combined, so that the prepared product has excellent physical and chemical properties of a PDMS membrane, high sensitivity of an SERS detection technology and high selectivity of MIT; the invention provides a new method for SERS detection and widens the application range.