4413 results about "Structural unit" patented technology

The invention belongs to the technical field of anion exchange membranes, and relates to a cross-linked polyaromatic piperidine anion exchange membrane and a preparation method thereof. The exchange membrane structure comprises a copolymer structure of the following repetitive structural units, the selected rigid main chain polyaromatic hydrocarbon can ensure the mechanical strength of the anion exchange membrane, meanwhile, the toughness of the anion exchange membrane is further enhanced by adopting a cross-linked structure, and a formed cross-linked network can reduce swelling of the anion exchange membrane, so that the anion exchange membrane is more stable in performance. The mechanical performance is improved; according to the invention, ether-free skeleton polyaromatic hydrocarbon is selected as a main chain and has the characteristic of strong alkali-resistant stability, six-membered nitrogen heterocyclic ions are adopted as functional groups, and a large steric hindrance structure can hinder nucleophilic substitution and elimination reaction, so that the alkali-resistant stability of the anion exchange membrane is improved, and the service life of the anion exchange membrane is prolonged. And in the # imgabs0 #, X is equal to 0.05 to 0.15.

The invention discloses a preparation method and application of a cell culture liver based on a microcarrier. The method comprises the steps of obtaining liver seed cells, preparing the microcarrier, culturing cells in vitro based on the microcarrier, preparing the cell culture liver and the like. The preparation method of the cell culture liver based on the microcarrier is provided for the first time, and the preparation scheme that a cell-microcarrier compound serves as a structural unit and is assembled into the cell culture liver after being mixed with an edible material is adopted, so that on one hand, simulation of a real liver lobule structure can be achieved, and on the other hand, simulation of the liver lobule structure can be achieved; the whole structure relation of liver lobules and connective tissues in liver tissues can be simulated, full reduction of animal liver appearance and structural characteristics is achieved, edible materials used in the preparation process are low in price and good in biocompatibility, and the preparation method is suitable for large-scale industrial production. Liver seed cells can be subjected to efficient amplification and albumin synthesis through three-dimensional culture on a microcarrier prepared on the basis of edible materials, so that the cell culture liver is close to a real animal liver in the aspect of nutrition.

The invention provides a floating type annular wave-resistant offshore photovoltaic structure. The floating type annular wave-resistant offshore photovoltaic structure comprises arc-shaped wave-resistant structure units, spring connectors, photovoltaic buoyancy tanks, photovoltaic modules, buoyancy tank mooring cables, mooring cables and pile anchors. The plurality of arc-shaped anti-wave structure units are flexibly and annularly connected through the spring connectors to form a floating type annular anti-wave structure; photovoltaic buoyancy tanks are fully paved in the circular ring of the floating type annular wave-resistant structure in parallel, and a photovoltaic module is fixedly mounted on the surface of each photovoltaic buoyancy tank. The structure main body of the novel floating type annular wave-resistant offshore photovoltaic structure adopts arc-shaped wave-resistant structures made of a high-density polyethylene material, the arc-shaped wave-resistant structures are connected into an integral circular ring through spring connectors, photovoltaic modules in the ring are protected and moored, a plurality of macromolecule buoyancy tank mooring cables are adopted in the ring to be connected with photovoltaic buoyancy tanks, and the photovoltaic buoyancy tanks are connected into a whole. The whole structure has certain flexibility and has the advantages of being small in steel consumption, high in weather resistance, low in building cost, high in wind wave resistance, easy and convenient to construct, good in power generation economical efficiency and the like.

The purposes of the present invention is: to provide an adhesive composition which has excellent adhesive force and holding properties in addition to excellent low dielectric properties; to provide an adhesive tape which has an adhesive layer that contains the adhesive composition; to provide a resin molded body which is molded from a resin composition that comprises the adhesive composition; to provide a composite structure which comprises the adhesive tape; to provide an automobile member which comprises the resin molded body or the composite structure; and to provide a method for producing a resin molded body using the composite structure.　The present invention provides an adhesive composition which contains: an acrylic copolymer that has a constituent unit derived from a (meth)acrylic acid alkyl ester, a constituent unit derived from an olefin-based polymer that has a polymerizable unsaturated double bond at an end thereof, and a constituent unit derived from a polar functional group-containing monomer; and a styrene-based elastomer that contains at least one substance selected from the group consisting of a block copolymer which has a block derived from a styrene-based monomer and a block derived from a conjugated diene-based monomer, and a hydrogenated product of the block copolymer.

Provided is a polyamide resin, which is a copolymer of a biodegradable polyamide, such as polyamide 2 to polyamide 4, and another polyamide, the polyamide resin having enhanced biodegradability. The polyamide resin contains a structural unit represented by Formula (1) and another polyamide structural unit, and a difference between a degree of randomness determined based on a proportion of each structural unit as determined by 1H-NMR measurement when structural units are assumed to have an ideal random sequence and a degree of randomness determined based on a proportion of carbonyl carbon of an amide group linking different structural units with respect to a total peak integrated value for carbonyl carbon as determined by 13C-NMR measurement is 0.10 or less, where in Formula (1), x is an integer of 1 or greater and 3 or less.

The invention discloses a PHA-acrylic acid structural unit water-based dispersion based on interface engineering regulation and control, a preparation method thereof and application of a paper-based barrier coating, and belongs to the technical field of high polymer materials, interface engineering and water-based coatings. The stable interface layer is constructed in situ between the crystalline PHA and the acrylic resin through the amphiphilic polymer, so that the problems of poor compatibility and film forming defects of a bio-based material are effectively solved. The dispersion can realize excellent waterproof, oil-proof and gas barrier effects by only needing a relatively low coating weight, and the material consumption is remarkably reduced. The unique gradient structure of the coating has excellent mechanical adhesive force and efficient re-pulping and recycling characteristics, and the technical defect that a traditional barrier coating is difficult to recycle is overcome. And an ideal solution with high performance and high safety is provided for green packaging.

The invention relates to the technical field of silicone rubber, and discloses flame-retardant and heat-insulating silicone rubber and a preparation method thereof.The flame-retardant and heat-insulating silicone rubber is obtained by reacting a flame-retardant aid with hollow glass beads and then adding the reaction product, methyl vinyl silicone rubber, hydroxyl silicone oil, a reinforcing agent, a flame retardant and a vulcanizing agent into an open mill to be mixed and vulcanized. The flame-retardant auxiliary agent contains a siloxane structural unit and is grafted on the surfaces of the hollow glass beads, so that the compatibility between the flame-retardant auxiliary agent and the methyl vinyl silicone rubber is improved, the hollow glass beads are more uniformly dispersed in a silicone rubber matrix, a uniform heat insulation network is formed, the heat conductivity is reduced, and the heat insulation performance is improved. The flame-retardant auxiliary agent contains nitrogen-rich triazine groups, and generates nitrogen and other non-combustible gases during combustion, so that the oxygen concentration of the combustion atmosphere can be diluted, and the limit oxygen index, flame retardance and high-temperature resistance of the silicone rubber are improved.

The invention relates to the technical field of ink, and discloses a preparation method of bio-based degradable water-based ink, which comprises the following steps: carrying out esterification polymerization on vanillin-based spiro acetal diglycidyl ether and diacid to obtain bio-based polyester resin, mixing and dispersing the bio-based polyester resin, petroleum-based resin, pigment, auxiliary agent and the like to obtain the bio-based degradable water-based ink. The bio-based degradable water-based ink is prepared. The bio-based resin contains a plurality of hydrophilic hydroxyl groups, has good solubility and dispersibility in the water-based ink, and generates denser hydrogen bonds and other cross-linking effects with the acrylic resin, so that the hardness of the ink is improved. Meanwhile, the polar hydroxyl groups also greatly enhance the hydrogen bond bonding and anchoring effect between the paint film and the base material, so that the adhesive force is improved. In addition, easily-hydrolyzed spiral acetal bonds, polyester structural units and other degradable chemical bonds in molecular chains of the bio-based resin provide more attack sites for water and microorganisms, the degradation rate is increased, and the degradable function is achieved.

The invention belongs to the technical field of organic synthesis, and particularly discloses an ammonia aromatic alkene modified near-infrared BODIPY fluorescent probe as well as a preparation method and application thereof.The near-infrared BODIPY fluorescent probe is obtained by adopting 6-(dimethylamino) nicotinic aldehyde to directionally modify the alpha position of BODIPY and constructing an expanded conjugated system through Knoevenagel condensation. Wherein dimethylamino provides a strong electron donating effect, a molecular structure is twisted into a non-planar configuration due to steric hindrance of a pyridine ring, pi-pi accumulation is reduced, and an ACQ effect is inhibited. According to the structural modification strategy, significant red shift of absorption / emission wavelength is realized by expanding a molecular pi-conjugated skeleton, and meanwhile, the stability of the BODIPY core and the quantum yield are effectively enhanced. The probe molecule can specifically recognize the diphenylalanine dipeptide structural unit by utilizing the synergistic coordination effect of the 2-aminopyridine derivative and the BODIPY mother nucleus, so that the selective detection of the Alzheimer's disease biomarker Abeta42 is realized, and a novel optical detection tool is provided for the early molecular diagnosis and targeted therapy of AD (Alzheimer's disease).

The invention belongs to the field of macromolecules, and discloses a polymer for a paper reinforcing agent, the polymer contains an acrylamide structural unit, a cationic structural unit containing a cationic group, and a functional structural unit for improving the rigidity or crosslinking density of the polymer; the weight-average molecular weight of the polymer is 0.5-1 million, and the dispersion coefficient is less than 3. After the polymer is applied to a paper reinforcing agent, the strength of paper can be improved, and meanwhile, the water filtering performance can be improved. Meanwhile, the invention also provides a preparation method of the polymer, a paper reinforcing agent and a preparation method of the paper reinforcing agent.

The invention provides a binder, negative electrode slurry, a negative electrode plate and a battery. The adhesive comprises a polymer, the polymer comprises an acrylic acid structural unit, a structural unit containing quaternary ammonium salt, a phenolic ether structural unit and a flexible structural unit, and the mass ratio of the acrylic acid structural unit to the structural unit containing quaternary ammonium salt to the phenolic ether structural unit to the flexible structural unit is (30-70): (1-10): (0.5-5): (5-20); the phenolic ether structural unit comprises at least one of an aromatic phenol structural unit and an aromatic ether structural unit. The binder provided by the invention synergistically provides a triple dispersion mechanism of electrostatic stability, surface adsorption and hydrophobic anchoring through the acrylic acid structural unit, the structural unit containing quaternary ammonium salt and the phenolic ether structural unit, so that the negative electrode slurry can form a long-term stable aqueous slurry system without depending on an additional dispersant. The binder forms a bactericidal and bacteriostatic barrier in the slurry, has a stable anticorrosion structure network, and is stable in electrochemical performance.

The invention relates to an ultralow-loss hollow-core anti-resonance optical fiber with a birefringence structure, which comprises an outer cladding and an inner cladding, the inner cladding is composed of anti-resonance structure units, the anti-resonance structure units are arranged along the circumferential direction of the inner wall of the outer cladding and are connected with the inner wall of the outer cladding, the inner cladding comprises four anti-resonance structure units, and the anti-resonance structure units are arranged along the circumferential direction of the inner wall of the outer cladding and are connected with the inner wall of the outer cladding. The four anti-resonance structure units are evenly distributed at intervals in the circumferential direction and comprise two long-axis anti-resonance structure units and two short-axis anti-resonance structure units, the two long-axis anti-resonance structure units are symmetrically arranged on the two sides of the inner wall of the outer cladding layer, and the two short-axis anti-resonance structure units are symmetrically arranged on the other two sides of the inner wall of the outer cladding layer. A central cavity wrapped by an inner wrapping layer formed by the four anti-resonance structure units forms an elliptical fiber core with a long axis and a short axis. According to the invention, the transmission loss can be reduced while the high birefringence performance is maintained, the shape of each part of the microstructure cladding is regular, and the preparation is convenient.

The invention provides copolymerized flame-retardant nylon containing nitrogen and phosphorus as well as a preparation method and application of the copolymerized flame-retardant nylon. The copolymerized flame-retardant nylon containing nitrogen and phosphorus is formed by copolymerizing a structural unit I and lactam or copolymerizing the structural unit I, diamine and binary acid, the nitrogen and phosphorus-containing copolymerized flame-retardant nylon belongs to a halogen-free flame-retardant environment-friendly high polymer material and is intrinsic flame-retardant nylon, so that the problems of flame retardant migration, compatibility with a base material and the like do not exist, excellent flame-retardant performance can be achieved under the condition of relatively low introduction amount of a flame-retardant structural unit, and meanwhile, excellent mechanical property and spinnability can be kept.

The invention discloses a low-dielectric polyimide film material and a preparation method and application thereof, and relates to the technical field of film material preparation, and the molecular structure of a polyimide copolymer in the polyimide film material comprises structural units shown in general formulas (1) and (2), the polyimide copolymer comprises aromatic ether, fluorine atoms or fluorine-containing groups and siloxane units, at least one of C and D in the structural units contains fluorine atoms or fluorine-containing groups, and the molar ratio of the content of the copolymerization components x: y: z is (1-90%): (1-50%): (1-30%). According to the preparation method, a batch feeding synthesis mode is adopted, molecular chain growth of polyamide acid is controlled through the feeding ratio, the salt forming effect of silicon-containing diamine and polyamide acid is avoided, and high-molecular-weight polyimide is obtained. The polyimide film prepared by the method has the characteristics of low dielectric constant and dielectric loss, low water absorption, good adhesion and the like, and can be applied to the fields of high-frequency and high-speed integrated circuits and the like.

The invention provides a composite photo-thermal hydrogel for seawater desalination and a preparation method and application thereof, the hydrogel has a structural unit of a structure as shown in a formula I. COF with photo-thermal performance is compounded with the hydrogel, and the hydrogel has a three-dimensional long-range ordered pore structure to promote transmission of water molecules; and the COF dispersed in the material contains porphyrin and a C = N double-bond connection structure, so that the material has excellent photothermal conversion efficiency. Therefore, under the irradiation of sunlight, the composite photo-thermal hydrogel disclosed by the invention can realize photo-thermal conversion to realize seawater evaporation, the seawater evaporation rate reaches 3.6 kgm <-1 > h <-1 >, and the performance is improved by about 3 times compared with that of a traditional carbon-based material. According to the preparation method of the composite photo-thermal hydrogel, large and complex equipment is not involved in the preparation method, the preparation technological process is simple, and industrial large-scale production is facilitated; and the reaction temperature in the preparation process is low, the energy consumption is also reduced, and the cost advantage is remarkable.

A separation membrane, a preparation method therefor and a use thereof in magnesium and lithium separation are provided. The separation membrane includes, in sequence, a base material layer, a porous support layer, a polyamide layer and a modification layer. Cross-linked polymers forming the modification layer has structural units provided by polyphenols and polyamines, at least some of the structural units provided by the polyphenols are connected to the polyamide layer via ortho positions of phenolic hydroxyl groups. The preparation method includes sequentially preparing the porous support layer, the polyamide layer and the modification layer on the base material layer. The method of preparing the modification layer includes under a first pressure, bringing one side of the polyamide layer into first contact with the polyphenol solution; then under a second pressure, bringing one side of the polyamide layer into second contact with the polyamine solution, to complete a self-assembly reaction.

The invention belongs to the field of water treatment, and particularly relates to a graphene-based quinone mediator membrane as well as a preparation method and application thereof. The graphene-based quinone mediator membrane comprises a membrane matrix, and graphene, amino imidazopyridine and humus which are dispersed in the membrane matrix, the membrane substrate is made of polyvinylidene fluoride / butadiene, the polyvinylidene fluoride / butadiene is a random copolymer of polyvinylidene fluoride and butadiene, and an anthraquinone modification unit is bonded on a butadiene structural unit of the random copolymer. The graphene-based quinone mediator membrane provided by the invention has very high initial denitrification rate and over-time denitrification rate.

The invention discloses a high-molecular-weight phosphamide aggregate flame retardant and a preparation method thereof.The method comprises the steps that phosphoryl dichloride compounds and piperazine anhydrous serve as raw materials, an amino-terminated phosphamide polymer is synthesized through a condensation reaction, and the phosphamide polymer flame retardant is obtained. The high-molecular-weight phosphamide aggregate flame retardant is obtained through a ring-opening reaction of amino-terminated groups and epoxy groups between the high-molecular-weight phosphamide aggregate flame retardant and triglycidyl isocyanurate. Compared with an existing small-molecule flame retardant, the flame retardant is higher in thermal stability, better in compatibility with a high polymer material matrix, not prone to migration and capable of achieving synergistic flame retardance due to the fact that the flame retardant contains phosphorus and nitrogen structural units at the same time, and when the prepared flame retardant is added into TPU, PC, EP, PET and other transparent matrixes, the flame retardance is improved. The flame retardant property of the transparent base material can be improved, and meanwhile, good mechanical property and high light transmittance can be kept. In addition, the preparation method disclosed by the invention is simple and easy to control, high in yield, wide in source of required raw materials, easy for industrial production and wide in industrial application prospect.

This anticorrosive coating composition comprises a main agent (I) and a curing agent (II), wherein: the main agent (I) contains an epoxy resin (a); the epoxy resin (a) contains at least one of a bisphenol A epoxy resin (a-11) and a novolac epoxy resin (a-12) each having a weight average molecular weight of 6,000-12,000; the curing agent (II) contains a polyamine (b) and an alkylphenol (c); the polyamine (b) contains an alicyclic polyamine (b-1) having a cyclic aliphatic hydrocarbon group to which an amino group is bonded and contains a non-alicyclic polyamine (b-2) having no cyclic aliphatic hydrocarbon group to which an amino group is bonded; at least one of the main agent (I) and the curing agent (II) includes a vinyl-based defoaming agent (d) that has a constituent unit derived from at least one monomer selected from the group consisting of alkyl (meth)acrylates, alkyl vinyl ethers, and olefins and that has a number average molecular weight of 30,000-100,000 or 300,000-2,000,000; the content of the alicyclic polyamine (b-1) is 30%-80% by mass of the solid content of the curing agent (II); the content of the non-alicyclic polyamine (b-2) is 2%-45% by mass of the solid content of the curing agent (II); the content of the alkylphenol (c) is 5%-60% by mass of the solid content of the curing agent (II); and the content of the vinyl-based defoaming agent (d) is 0.005-3 parts by mass with respect to 100 parts by mass of the anticorrosive coating composition.

The invention relates to the technical field of adsorption materials, and discloses a post-modified imine-COF adsorbent and a preparation method and application thereof, the adsorbent comprises the following structural units: a COF skeleton, which is a two-dimensional or three-dimensional porous skeleton formed by an aromatic aldehyde monomer and an amino monomer through a Schiff base reaction; the imine group is formed in a COF skeleton through a post-modification reaction, and the imine group is-C = NR, r is selected from one or more of a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted cycloalkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted heterocyclic group and a hydrogen atom. The adsorbent retains excellent structural characteristics of the COF material, realizes high density and uniform distribution of functional groups, and avoids interference of functional monomers on crystal nucleation and growth, so that the adsorption performance of the adsorbent is improved, and the adsorbent can efficiently capture rare earth when being applied to a rare earth-containing solution.

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 relates to a multilayer packaging material with high barrier property and application thereof. The multi-layer packaging material at least comprises three layers, namely a layer A, a layer B and a layer C, wherein the layer B is located between the layer A and the layer C; the layer A is prepared from the following raw materials: first biodegradable polyurethane and a cellulose nanocrystal graft which is obtained by performing grafting treatment on cellulose nanocrystal after hydrophobic modification, and the content of the cellulose nanocrystal graft is 1wt%-10wt% of that of the first biodegradable polyurethane; the raw material of the layer B comprises biodegradable polyester containing a glycollic acid structural unit, and the content of the glycollic acid structural unit is not less than 60% mol; the raw material of the layer C comprises second biodegradable polyurethane. The hydrophobic modified cellulose nanocrystals are uniformly dispersed in the layer A, so that the adsorption of water vapor on the layer A is reduced, the permeation of the water vapor is hindered, and the barrier property of the whole material is improved.

The present invention discloses an X-shaped negative Poisson's ratio local resonance module and its supporting metamaterial disc structure. The X-shaped negative Poisson's ratio local resonance module includes an X-shaped structural wall, an X-shaped negative Poisson's ratio structural unit and a local oscillator, wherein the local oscillator includes a soft coating layer and a cylindrical core, and the local oscillator is fixed on the X-shaped negative Poisson's ratio structural unit in an embedded form; the supporting metamaterial disc structure is composed of a plurality of X-shaped negative Poisson's ratio local resonance modules. The X-shaped negative Poisson's ratio structural units are circumferentially distributed around the outer wall of the inner circular ring column in the X-shaped structural wall to the inner wall of the outer circular ring column, and the outer wall of the inner circular ring column and the inner wall of the outer circular ring column are connected by the X-shaped structural unit wall. The X-shaped negative Poisson's ratio local resonance module is installed on a beam-type or tube-type base structure through the inner circular ring column. The present invention can achieve multi-scale and multi-level vibration suppression through the X-shaped negative Poisson's ratio local resonance module, improve the stability of the disc-shaped parts, and is easy to install and convenient to process.

The invention relates to an acylhydrazone bond-connected covalent organic framework material, in particular to an acylhydrazone bond-connected covalent organic framework material as well as a preparation method and application thereof, and aims to overcome the defects of various materials for adsorbing Pd (II) in one aspect or the defects of poor stability and durability in high-acidity and high-radioactivity environments. Or the adsorption selectivity on Pd (II) is not strong. As an emerging crystalline organic porous polymer, the covalent organic framework is mainly formed by connecting pure organic structural units through dynamic covalent bonds, has the advantages of permanent high porosity, low density, high chemical stability, high thermal stability and the like, and is expected to realize Pd (II) adsorption in strong acid and ray irradiation environments.

The invention provides polyester and a preparation method and application thereof, the polyester comprises a structural unit derived from the following monomer components: at least one monomer component I selected from hydroxybenzoic acid or hydroxynaphthoic acid; and at least one monomer component II, wherein the monomer component II is selected from p-hydroxybenzoic acid containing a substituent group. A small amount of the monomer component II is introduced into the polyester material, interaction points are provided for chain segments of the polymer, the chain segments are promoted to form a branched structure, and therefore the melt strength of the polymer is well improved.

The embodiment of the invention provides a binder, a positive plate and a battery, the binder comprises a nitrile structural unit, an ether structural unit, a nitrogen heterocyclic structural unit and a sulfonic acid structural unit, and the swelling degree of the binder is 20-40%. According to the present invention, the adhesion, the flexibility, the swelling resistance and other properties of the binder can be improved, the flexibility of the electrode plate using the binder can be improved, and the electrochemical properties such as the improvement of the first efficiency and the cycle life of the battery can be considered.

Provided is a photosensitive resin composition having excellent low-temperature curability and capable of providing a cured resin film having sufficient solvent resistance or sufficient hardness. Also, provided are a color filter having excellent solvent resistance or excellent hardness, and an image display element having same. A photosensitive resin composition according to the present invention contains a copolymer (A), a reactive diluent (B), a photopolymerization initiator (C), and a solvent (D).　The copolymer (A) contains a structural unit (a), a structural unit (b), and a structural unit (c). The structural unit (a) has at least one selected from among an active methylene group having an alkoxycarbonyl group attached thereto, and an active methine group having an alkoxycarbonyl group attached thereto. The structural unit (c) has an acid group.

The invention belongs to the technical field of electromagnetic wave functional materials, and particularly relates to a nested split ring wave-absorbing metamaterial and a preparation method thereof. The wave-absorbing metamaterial sequentially comprises an FSS metal structure layer, a dielectric layer and a metal matrix layer from top to bottom in the thickness direction, the FSS metal structure layer is formed by distributing structure units in a periodic array mode, each structure unit is composed of a double-opening outer ring shaped like a Chinese character'hui 'and a double-opening inner ring, the double-opening outer ring is a split square, and the double-opening inner ring is a hollow square. The structural units are symmetrically arranged about the diagonal line of the dielectric layer. The FSS metal structure layer designed by the invention has anisotropy, so that the polarization direction of an incident wave can be rotated by 90 degrees in a reflection mode. By means of the design, the two functions of electromagnetic wave absorption and polarization conversion are achieved at the same time, and meanwhile the effect of multiband wave absorption is achieved. Within the frequency band of 4 GHz to 18 GHz, the maximum wave-absorbing strength of the nested wave-absorbing metamaterial is as high as-30 dB, and the effective wave-absorbing bandwidth can reach 7.5 GHz.

The invention relates to the field of ion exchange resin, and discloses quaternary ammonium type anion exchange resin, a preparation method and application thereof, and a catalytic hydration reaction method of an epoxy-containing compound. The anion exchange resin comprises a resin matrix # imgabs 0 # and a quaternary ammonium group connected with the resin matrix # imgabs 1 # through an alkylene group; wherein the resin matrix # imgabs2 is a hydrogenated styrene-dienylbenzene copolymer, and the styrene-dienylbenzene copolymer contains a styrene structural unit as shown in a formula (1), a dienylbenzene structural unit as shown in a formula (2), a # imgabs3 # formula (1) and a # imgabs4 # formula (2); in the formula (1), R11 is alkyl or hydrogen, and R12 is alkyl or hydrogen; in the formula (2), n is an integer between 0 and 2. The quaternary ammonium type anion exchange resin provided by the invention has excellent swelling resistance.

The invention discloses a hypha mineral composite bionic sand stabilization unit body and a preparation method thereof, and relates to the technical field of sand stabilization, the interior of the unit body is provided with a bionic three-dimensional porous skeleton structure, the unit body comprises a porous core layer, a porous core layer and a porous core layer, the porous core layer takes cleaning sand grains with the particle size of 0.1-2 mm as a sand-based carrier; uniformly mixing and curing with organic nutrient substances, mineral precursors and strain spores; the composite reinforcing layer is formed by interweaving and compounding a mycelium network formed by germination and growth of strain spores, mineral crystals generated by in-situ mineralization induced by metabolic activity of hyphae and a plant fiber reinforcing material which is externally added and embedded into the pores in the pores of the porous core layer; according to the hypha mineral compounded bionic sand stabilization unit body and the preparation method thereof, mold pressing or 3D printing prefabrication is adopted, the structure is controllable, and standardized production and transportation are facilitated; and through a controllable fermentation and gradient dehumidification mineralization culture process, hyphae and minerals are ensured to be uniformly and fully compounded in pores, and the product quality is stable.