38results about How to "Realize construction" patented technology

The invention belongs to the field of super-amphiphobic materials and discloses water-borne epoxy resin and a super-amphiphobic coat as well as a preparation method and application of the water-borne epoxy resin and the super-amphiphobic coat. The water-borne epoxy resin is a polymer with the structural formula of P (A-r-B) and is obtained through the polymerization reaction of a water-soluble monomer A and a monomer B, wherein the mass ratio of A and B is 1: (0.2-20), and the tail end of the monomer B is an epoxy group. The obtained water-borne epoxy resin is dissolved into solvent, then a fluorine-containing substance, particles and a catalyst are added to the solvent to obtain a mixed solution; the mixed solution is stirred for reaction, and distilled water is dropwise added to form a water solution; a base material is soaked in the water solution, or the water solution is sprayed on the surface of the base material, and the super-amphiphobic coat is formed on the surface of the base material after drying treatment. The super-amphiphobic coat is simple to construct and has excellent lyophobic and oleophobic properties and excellent durability.

The invention discloses a composite beam wherein the concrete slab is combined with upside and underside of the steel beam with corrugate steel web so as to increase rigidity of the cross section. A prestress concrete composite beam with corrugate steel web contains steel beam, upper and lower concrete slab combined with the upside and underside of the steel beam. The steel web is made of corrugate steel plate with the same corrugate pleat as each other in vertical direction of the beam, thereby increasing resistance to bending. The pylome is formed in upside and underside of the steel beam. Many binding reinforcements insert into the pylome in horizontal direction and embed into the upper and lower concrete slab. Then the steel beam is combined with the upper and lower concrete slab.

The invention discloses an Ag NCs and G-quadruplex / NMM system-based label-free DNA molecular device. According to the device, a nano-silver cluster synthesized by taking a dsDNA-loop-C6 structure as a template is constructed; through constructing two G4-quadruplex structure / NMM fluorescent probes, fluorescent outputs of yellow and red are formed; a double-output molecular logic gate is constructed; yellow and red fluorescence intensities are taken as judging basis; and when the normalized numerical values of the fluorescence intensities are greater than 0.45, the outputs are 1, and otherwise, the outputs are 0. The inputs of different DNA chains generate different influences on the two fluorescent probes, and different fluorescent signals are output. On the basis of above principle, five DNA molecular logic gates such as a 2-to-1 coder, a 4-to-2 coder, a 1-to-2 decoder, a half adder and a half subtractor are constructed, and the DNA molecular logic gates can be used for detecting different DNA sequences.

A building process for a deep sea spar platform includes the steps: firstly, respectively building an upper hard tank ring half section and a lower hard tank ring half section on a slide way; secondly, mounting lifting devices on the periphery of the upper ring half section; thirdly, continuously lifting the upper hard tank ring half section to a set position; fourthly, folding and butting the lower hard tank ring half section and the upper hard tank ring half section into an integral ring section; fifthly, leading the integral ring section to slide out of a mounting device; sixthly, repeating the step two to the step five until a plurality of integral ring sections are built; seventhly, folding and connecting the integral ring sections into an integral hard tank; eighthly, respectively mounting a truss and a soft tank on slide shoes positioned on sliders; and ninthly, completing building of a spar platform body by means of butting and folding. By the aid of the building process, building precision of the platform is improved, construction period is shortened, a building procedure is little susceptible to environment (wind) load effect, a requirement on site space is lowered, and important technical support is provided for deep-sea resource development.

The invention discloses a full-round machine-room-less sightseeing elevator to solve the problem of poor effect of low angle sightseeing of the machine-room-less sightseeing elevator in the prior art. The full-round machine-room-less sightseeing elevator comprises a car, a car door and a portal crane and is characterized in that the car comprises a surrounding cylindrical car wall, a car roof at the top and a car platform at the bottom, the car door is of an arc shape and is matched with the shape of the car wall, the portal crane is connected below the car platform, and the car door, the car wall and the car roof are all made of transparent materials. With the improvement of individuation and high-quality life demands of people, people raise large numbers of requirements for sightseeing effects and appearance characteristics and the like when selecting a sightseeing elevator, but elevator manufacturers are limited to complementary products such as portal cranes, and accordingly the full-round machine-room-less sightseeing elevator is not developed; therefore, the full round machine-room-less sightseeing elevator is designed to solve the problems.

The invention discloses magnetic composite particles and a preparation method and application thereof. The magnetic composite particles are of a core-shell satellite structure, the magnetic composite particles are prepared from silver-shell magnetic beads and gold nanorods, and the surfaces of the silver-shell magnetic beads are combined with the gold nanorods with poly(2-vinylpyridine); the silver-shell magnetic beads are composed of manganese ferrite and silver shells continuously wrapping the manganese ferrite. The preparation method of the magnetic composite particles comprises the steps that 1, the silver-shell magnetic beads are added into a poly(2-vinylpyridine) solution, ultrasonic treatment is conducted, and the poly(2-vinylpyridine) modified silver-shell magnetic beads are obtained; 2, a gold nanorod solution is prepared; 3, the poly(2-vinylpyridine) modified silver-shell magnetic beads and the gold nanorod solution are mixed, an ultrasonic reaction is conducted, the magnetic composite particles are obtained, and the magnetic composite particles can serve as an SERS reinforced substrate for detection application. The magnetic composite particles have the very good magnetic response capability and SERS property, and the preparation method is simple in technology, high in universality and high in applicability.

The invention discloses a construction method for long-span cast-in-situ unbonded prestressed hollow floor slabs. The method comprises the following steps: step 1, installing a floor slab soffit formwork; step 2, determining the installation position of ribbed beams and LPM light tubes, and drawing the installation position of the LPM light tubes and the side lines of the ribbed beams on the surface of the soffit formwork according to the design requirement; step 3, binding ribbed beam reinforcement bars and floor slab bottom reinforcement bars; step 4, installing positioning bars; step 5, laying prestressed reinforcement bars; step 6, laying hydropower pipelines; step 7, laying the LPM light tubes; step 8, erecting an end formwork; step 9, binding floor slab panel reinforcement bars; step 10, pouring and maintaining concrete; and step 11, tensioning the prestressed reinforcement bars. The construction method has the advantages that as the LPM light tubes are additionally arranged in the middle part of the floor slabs, on the one hand, the dead load of the floor slabs is reduced, and the construction of long-span building structures is realized; on the other hand, the thermal insulation properties of buildings are ensured; and the prestressed method is adopted in the floor slab construction process, the strength of the floor slabs is enhanced, and the safety and the durability of the floor slabs are ensured.

The invention discloses a self-stabilization fish scale pit type ecological baffle wall. The ecological baffle wall comprises baffle wall units, wherein cavities which longitudinally run through the baffle wall units are formed in the middles of the baffle wall units and are internally sleeved with ecological replacement tanks for planting plants, nutrient for supplying nutrients to the plants ispaved in the ecological replacement tanks, locking bulges are symmetrically arranged on two side walls of the bottom surfaces of the front parts of the baffle wall units, and locking grooves are symmetrically formed in two side walls of the top surfaces of the middles of the baffle wall units and are matched with the locking bulges; and the baffle wall units are arrayed in a fish scale manner oneby one so as to form the ecological baffle wall, the adjacent baffle wall units on the upper and lower layers are arranged in a staggered manner, and the locking bulges of the baffle wall unit on theupper layer stretch into the locking grooves of the baffle wall unit on the lower layer so as to form limiting connection. Compared with the prior art, the self-stabilization fish scale pit type ecological baffle wall has the advantages that the self-stability is good, the construction is simple, large-size mechanical equipment is not required, the ecological baffle wall can resist corrosion, hasgood greening effect and can well meet the biodiversity, a hydrophilic observation platform can be provided for residents, a self-rescue life way is provided for drowning people, and the water ecological functions of ecological protection slopes are realized.

The invention relates to an electrochemical induced mineral deposition system and method. The deposition system comprises a container for containing an electrolyte solution, an electrode bearing plate fixedly arranged on the container and suspended above the electrolyte solution, a stirring assembly which is arranged on the container and has a stirring end arranged in the electrolyte solution and has an adjustable rotating speed, and a cathode material and an anode material which are movably arranged on the electrode bearing plate and partially arranged in the electrolyte solution, wherein the cathode material and the anode material are connected with an external power supply through leads. Compared with the prior art, the electrochemical induced mineral deposition system and method can realize the flexible design of the structure of deposited mineral material, accurate control of influencing factors in the induced deposition process and controllability of the performance of the deposited mineral material, thereby further realizing the deep research on electrochemical induced mineral deposition technology, and laying a solid foundation for the application of the technology in the marine environment.

The invention provides a method for preparing polycarboxylic acid / methyl-cyclopentadienyl-manganese-tricarbony (MMT) nanocomposites by the adoption of atom transfer radical polymerization (ATRP) technique. Firstly, NaOH is adopted to regulate the potential of hydrogen (pH) value of a water-soluble olefine acid class monomer water solution to 8.5-9, then organic modification montmorillonite, cuprous halide catalysts and catalyst ligand are added into the water-soluble olefine acid class monomer water solution, again, under the protection of nitrogen or inert gases, a reaction system is heated through water bath to 60-90 DEG C to undergo a stirring reaction for 12-24 hours, and a polycarboxylic acid / MMT nanocomposite solution is obtained. Ion exchange of the polycarboxylic acid / MMT nanocomposite solution is carried out through a strong acid-stage cation exchange column, liquid is collected and dried, and the polycarboxylic acid / MMT nanocomposites are obtained. The prepared polycarboxylic acid / MMT nanocomposites are narrow in molecular weight distribution, orderly and uniform in structure, stable in performance, and capable of achieving construction of single intercalation type nanocomposites or exfoliation type nanocomposites.

The invention discloses a high-thermal-conductivity low-viscosity epoxy resin molding compound for semiconductor packaging and a preparation method of a heat-conducting component of the high-thermal-conductivity low-viscosity epoxy resin molding compound. The molding compound is composed of 50-100 parts by weight of epoxy resin, 40-100 parts by weight of a curing agent, 3-5 parts by weight of an ion capturing agent, 2-6 parts by weight of a coupling agent, 400-600 parts by weight of a hybrid filler, 2-5.25 parts by weight of a flame retardant and 1-2.5 parts by weight of a coloring agent. The heat-conducting component is formed by assembling alpha crystal form aluminum oxide microspheres (10-50 microns) and aluminum oxide nanosheets through chemical bonds, and the mass ratio of the alpha crystal form aluminum oxide microspheres (10-50 microns) to the aluminum oxide nanosheets is (2-10): 1. The method comprises the steps of assembling spherical aluminum oxide and flaky aluminum oxide into a hybrid filler according to a certain component ratio through chemical bonding, adding the hybrid filler into an epoxy molding compound mixture, and carrying out high-speed dispersion, mixing, crushing, mold pressing and other processes to form the molding compound. The prepared epoxy resin molding compound has high heat conductivity coefficient and lower internal stress, the spiral flow length is not less than 50 inches, and the typical value of the heat conductivity coefficient can reach 4.3 W / mK.

The invention discloses a self-stabilizing fish-scale pit ecological retaining wall, which includes retaining wall units. An up-down penetrating hollow cavity is formed in the middle of each retainingwall unit, each cavity internally sleeves an ecological replacement box for planting plants, each ecological replacement box is internally laid with concrete feeding nutrients for the plants, lockingprotrusions are arranged symmetrically on the two side walls of the bottom face of the front part of each retaining wall unit, locking grooves are formed symmetrically in the two side walls of the top face of the middle of each retaining wall unit, and the locking protrusions are matched with the locking grooves. The retaining wall units are arranged one by one in a fish-scale pattern to form theecological retaining wall, the upper and lower adjacent retaining wall units are interleaved, and the locking protrusions of the retaining wall unit on the upper layer extend into the locking groovesof the retaining wall unit on the lower layer to form limiting connection. Compared with the prior art, according to the self-stabilizing fish-scale pit ecological retaining wall, the advantages of good self-stability, easy construction, no need for large mechanical equipment, corrosion resistance and good greening effect are achieved, the biodiversity is well met, a water-friendly viewing platform can be provided for residents, a self-saving way out can also be provided for water-falling people, and the water ecological function of ecological slope protection is achieved.

The invention provides condensation type organic silicon resin aerogel and a preparation method thereof. Under the catalysis of a gel catalyst, condensation polymerization reaction is performed by hydroxyl-terminated silicon resin and a siloxane crosslinking agent, and after gelation and aging, wet gel is obtained by solvent replacement, supercritical drying and post-curing treatment. According tothe condensation type organic silicon resin aerogel and the preparation method thereof, by introducing the siloxane crosslinking agent and the gel catalyst into a solution of the hydroxyl-terminatedsilicon resin, condensation type organic silicon resin wet gel with a crosslinked network structure is prepared, then condensation type organic silicon resin aerogel is prepared by solvent replacement, supercritical drying and post-curing, and the technical problem that in prior art, condensation type silicon resin aerogel cannot be prepared due to the fact that the wet gal cannot be prepared fromcommercial hydroxyl-terminated silicon resin is solved.

The invention relates to an integrated chimney and cooling tower structure system of a diagonal cable net and a construction method thereof. According to the system, a chimney and an air cooling towerare combined, the chimney adopts a reinforced concrete structure and is built in the center of the air cooling tower, the air cooling tower adopts a tension structure, and a structure membrane material is laid on the outer side; ground assembly is adopted in construction, then the chimney is hoisted to a certain height, and the chimney is fixed to a concrete chimney through stay cables; and the lower portion of a hyperbolic structure cable is tensioned until the structure reaches a certain rigidity, and an inhaul cable is arranged in the middle of the chimney to be anchored to a foundation inorder to enable the chimney to keep certain compression stability. According to the system, the chimney is combined with the air cooling tower, so that the possibility of building the air cooling tower by using a flexible material is realized, and the air cooling tower can be spliced and tensioned on site; a hoisting mode after ground assembly is adopted, so that high-altitude operation is effectively reduced; chimney construction land can be effectively saved, the using amount of concrete is reduced, and on-site wet operation is reduced; and the structural membrane material is light in selfweight and can achieve a higher height, and the chimney provides lateral support for the cable net and can resist a larger wind suction load.

The invention relates to a paddy field soil ridge construction device and a construction method thereof, comprising: a frame body for erecting on the soil ridge, the bottom of the frame body is located on both sides of the soil ridge, and a number of rollers are provided for placing on the ground and Drive the frame body to move back and forth along the soil ridge; the soil pressure mechanism corresponding to the soil ridge and with an inverted U-shaped vertical section is installed on the frame body with adjustable height; and the cross section is "eight" shaped and installed on the soil pressure mechanism. The retracting mechanism at one end of the mechanism, the retracting mechanism is opened away from the end of the soil compacting mechanism in a direction away from the soil ridge, and the retracting mechanism communicates with the interior of the soil compacting mechanism to form a communication channel for accommodating the soil ridge. The invention effectively solves the problem of difficult construction of soil ridges in paddy fields, uses a building device to repair and compact the soil ridges, saves time and labor, and the device has simple structure, convenient operation, low cost, and can be applied to complex terrains.

The invention discloses a general assembly process of a 40,000-ton ore sand ship broadside block. The general assembly process comprises the following steps that in stage 1, a position line of a pieron a general assembly platform is marked out; in stage 2, longitudinal bulkheads are hoisted to the general assembly platform in a segmented mode and placed on piers; in stage 3, longitudinal bulkheadsubsections are adjusted; in stage 4, the heights of the head and the tail of the longitudinal bulkhead subsection are checked; in stage 5, the longitudinal bulkheads are fixed to the general assembly platform in a segmented mode; in stage 6, the outboard side is hoisted to the general assembly platform in a segmented mode and placed on the pier; in stage 7, outboard subsections are adjusted; instage 8, the heights of the heads and tails of the outboard subsections are checked; in stage 9, the outboard subsections and the longitudinal bulkhead subsections are temporarily fixed; and in stage10, splicing seams of the outboard subsections and the longitudinal bulkhead subsections are welded. According to the general assembly process of the 40,000-ton ore sand ship broadside block, the manufacturing period can be greatly shortened, waste of manpower and material resources is reduced, and the production efficiency is improved.

The invention discloses a general grouping process for the general section of the side of a 400,000-ton ore ship, including stage one, drawing the position line of the pier on the general grouping platform; stage two, hoisting the longitudinal bulkhead to the general grouping platform in sections and put it on the pier; stage three, adjust the longitudinal bulkhead section; stage four, check the height of the front and rear of the longitudinal bulkhead section; stage five, fix the longitudinal bulkhead section on the general group platform; stage six, The outboard section is hoisted to the general assembly platform and rested on the pier; stage seven, adjust the outboard section; stage eight, check the height of the bow and tail of the outboard section; stage nine, separate the outboard section and the longitudinal bulkhead Temporary fixation between sections; stage ten, welding the joints between the outboard section and the longitudinal bulkhead section. The general assembly process of the general side section of the 400,000-ton ore ship of the present invention can greatly shorten the production period, reduce the waste of manpower and material resources, and improve the production efficiency.

The present invention proposes a condensation-type silicone resin airgel and its preparation method. Under the catalysis of the gel catalyst, the condensation polymerization reaction is carried out by the hydroxyl-terminated silicone resin and the siloxane crosslinking agent, and after gelation and aging The wet gel was obtained by solvent replacement, supercritical drying and post-curing. The present invention introduces a siloxane crosslinking agent and a gel catalyst into a solution of hydroxyl-terminated silicone resin to prepare a condensation-type organic silicon resin wet gel with a crosslinked network structure, and then undergoes solvent replacement to supercritically Dry and post-cure to prepare condensation-type silicone resin airgel, which solves the technical problem that the existing technology cannot use commercial hydroxyl-terminated silicone resin to prepare wet gel, and then cannot prepare condensation-type silicone resin aerogel .

The invention relates to a linear actuator with a layered microphase structure and a preparation method thereof. The linear actuator with a layered microphase structure is a fiber or a spline, and the substrate is composed of a layer A (by block copolymer X and block copolymer Y) Composed of A block) and B@C composite layer (composed of B block in block copolymer X and C block in block copolymer Y, the two are combined by hydrogen bond or ionic bond) alternately connected ; The preparation method is: after the block copolymer X, the block copolymer Y and the organic solvent are made into a mixed solution, the mixed solution is processed into a film as a casting solution and then cut into splines, or the mixed solution is used as a spinning solution Processed into fibers; block copolymer X and block copolymer Y are ABA type triblock copolymer and ACA type triblock copolymer, or ABA type triblock copolymer and AC type diblock copolymer, Or AB type diblock copolymer and ACA type triblock copolymer. The invention effectively solves the problems of small work and instability of the current linear driver.

The invention relates to a method for preparing chiral inversion graphene liquid crystal through nanofluid rectification. The material is formed by the outward migration of sodium alginate guided by calcium ions with components including sodium alginate, glucose and graphene oxide GO. Polymer nanofluids, and driven GO inversion were obtained. The method of the invention is simple to operate and easy to produce on a large scale, and the prepared liquid crystal microfiber has a long-range ordered structure, a stable topological configuration and a controllable optical appearance. It has wide application prospect.

The invention discloses a stone curtain wall decoration profile assembly and a stone curtain wall construction method. A stone curtain wall decoration structure includes a hanging plate and a connecting plate set, each hanging plate is provided with one or more stone grooves, the stone grooves are internally configured to accommodate strip-shaped stone, a positioning projection and a positioning groove are respectively formed in the relative two side walls of the hanging plate, one end of the connecting plate set is connected with a building stand column, and the other end of the connecting plate set is connected with the hanging plate. When a plurality of hanging plates exist, the positioning projection of one of the two hanging plates can fit in the positioning groove of the other hanging plate. The stone curtain wall decoration profile assembly can better lower the possibility of stone falling off, more diverse stone curtain walls can be realized, and the personalized needs of userscan be better met.

The invention provides a method for preparing polycarboxylic acid / methyl-cyclopentadienyl-manganese-tricarbony (MMT) nanocomposites by the adoption of atom transfer radical polymerization (ATRP) technique. Firstly, NaOH is adopted to regulate the potential of hydrogen (pH) value of a water-soluble olefine acid class monomer water solution to 8.5-9, then organic modification montmorillonite, cuprous halide catalysts and catalyst ligand are added into the water-soluble olefine acid class monomer water solution, again, under the protection of nitrogen or inert gases, a reaction system is heated through water bath to 60-90 DEG C to undergo a stirring reaction for 12-24 hours, and a polycarboxylic acid / MMT nanocomposite solution is obtained. Ion exchange of the polycarboxylic acid / MMT nanocomposite solution is carried out through a strong acid-stage cation exchange column, liquid is collected and dried, and the polycarboxylic acid / MMT nanocomposites are obtained. The prepared polycarboxylic acid / MMT nanocomposites are narrow in molecular weight distribution, orderly and uniform in structure, stable in performance, and capable of achieving construction of single intercalation type nanocomposites or exfoliation type nanocomposites.

The invention discloses an integrally-tensioned integrated chimney and cooling tower structure system and a construction method thereof. According to the system, a chimney and an air cooling tower arecombined, the chimney is of a reinforced concrete structure and is built in the center of the air cooling tower, the air cooling tower is of a tensioning structure, and structural membrane materialsare laid on the outer side of the air cooling tower; ground assembly is adopted in construction, then the chimney is hoisted to a certain height, and the chimney is fixed to a concrete chimney throughstay cables; and the lower portion of a hyperbolic structure cable is tensioned until the structure reaches a certain rigidity, and an inhaul cable is arranged in the middle of the chimney to be anchored to a foundation in order to enable the chimney to keep certain compression stability. According to the system, the chimney is combined with the air cooling tower, so that the possibility of building the air cooling tower by using a flexible material is realized, and the air cooling tower can be spliced and tensioned on site; the mode of hoisting after ground assembly is adopted, so that high-altitude operation is effectively reduced; chimney construction land can be effectively saved, the using amount of concrete is reduced, and on-site wet operation is reduced; and the structural membrane material is light in self weight and can achieve a higher height, and the chimney provides lateral support for the cable net and can resist a larger wind suction load.

The invention belongs to the technical field of gas sensor preparation, and discloses a methanol sensor based on a hollow hexagonal Co3O4 material, a preparation method and application. The methanol sensor based on the hollow hexagonal Co3O4 material comprises a platinum lead, a gold electrode, a ceramic tube, a gas sensitive material layer and a nickel-chromium alloy heating coil. The ceramic tube is an aluminum oxide ceramic tube, and the aluminum oxide ceramic tube is provided with two Au electrodes and four Pt leads; the Co3O4 gas sensitive material layer uniformly covers the outer surface of the aluminum oxide ceramic tube; and the nickel-chromium alloy heating coil penetrates through the inner side of the ceramic tube and is used for controlling the working temperature of the gas sensor. According to the invention, the Co3O4 gas sensitive material is successfully synthesized by a one-step hydrothermal method, the synthesis method is simple and is low in cost; ammonium fluoride is used as a structure-directing agent, so that the construction of a hollow three-dimensional structure is achieved, the synthesis method is simple, and the cost is low.

A chimney-tower-integrated structural system with oblique cable nets and its construction method. The chimney is combined with the air-cooling tower. The chimney adopts a reinforced concrete structure and is built in the center of the air-cooling tower. The air-cooling tower adopts a tension structure, and structural membrane materials are laid on the outside . The construction is assembled on the ground, then hoisted to a certain height, and fixed on the concrete chimney by cables. The lower part of the hyperbolic structural cable is stretched until the structure reaches a certain rigidity. In order to keep the chimney stable under pressure, a stay cable is set in the middle of the chimney and the foundation is anchored. By combining the chimney with the air-cooling tower, the present invention realizes the possibility of building an air-cooling tower with flexible materials, which can be spliced ​​and stretched on site; the method of hoisting after ground assembly is adopted, which effectively reduces high-altitude operations; can effectively save chimney construction land and reduce concrete Reduce the amount of wet work on site; the structural membrane material is light in weight and can achieve a higher height, and the chimney provides lateral support for the cable net, which can resist greater wind suction load.

The invention discloses a method for preparing a structural color three-dimensional array pattern based on fixed liquid droplets, mainly combining multi-axis manipulator positioning and an automatic continuous ink supply system, adopting colloid particle assembly and gel curing methods in hydrophilic-hydrophobic patterning A three-dimensional structured color array pattern with controllable morphology and adjustable layer number is deposited on the substrate. The method can realize the formation of fixed liquid droplets, ensure the uniform distribution of printing ink on the substrate, and at the same time, the liquid droplets can be deposited multiple times in the vertical direction to realize the construction of a multi-layer structure. The method for preparing the structural color three-dimensional array pattern proposed by the present invention has the advantages of simple process, arbitrary design of microarray pixel point shape, strong pattern adjustability, uniform color, and good repeatability. At the same time, using multiple colloidal inks in parallel can not only Realize colorful pattern display, also can realize the construction of the optical coding array with multi-layer structure.