30results about How to "Improve sound absorption performance" patented technology

The invention provides a composite Helmholtz sound absorption structure with a porous material as a substrate, the composite Helmholtz sound absorption structure comprises a plurality of Helmholtz sound absorption units with different absorption peak frequencies, the Helmholtz sound absorption units are arranged in a periodic rectangular array, the sound absorption directions of the Helmholtz sound absorption units are the same, and the Helmholtz sound absorption units are connected in parallel. When the composite Helmholtz sound absorption structure absorbs sound, a strong coupling relation is formed between the Helmholtz sound absorption units so as to optimize the sound absorption performance of the composite Helmholtz sound absorption structure. Under the condition of limited thickness, the Helmholtz sound absorption units which are arranged in a periodic array and are connected in parallel can be utilized to realize high-efficiency sound absorption at a low frequency band.

The invention relates to the technical field of sound-absorbing materials, in particular to a foaming sound-absorbing material with a high aperture ratio structure and a preparation method and application thereof.The foaming sound-absorbing material comprises one or more of polylactic acid, poly (adipic acid) / butylene terephthalate and polyhydroxyalkanoate, the density of the foaming sound-absorbing material is 0.04-0.08 g / cm < 3 >, and the porosity of the foaming sound-absorbing material is 20-30%. The aperture ratio of the foaming sound absorption material is higher than 60%. According to the invention, the polymer foaming sound absorption material with high aperture ratio can be prepared without adding other fillers and assistants, the prepared foaming sound absorption material has the characteristics of high aperture ratio, small density and the like, and the foaming sound absorption material can realize efficient absorption of sound waves in a thickness range of 10 mm.

The invention discloses an expanded porous porcelainized aggregate acoustic board and a preparation method and application thereof.The preparation method comprises the following steps that phosphorus mud, waste incineration fly ash and steel slag are dried and subjected to ball milling, and then powder is obtained; uniformly mixing the powder of each raw material with the expanding agent in proportion, adding water, mixing and granulating to prepare an aggregate biscuit; and stacking the aggregate biscuit in a mold to form a plate shape, then drying the plate shape along with the mold, preheating at 400-500 DEG C, heating to 1100-1200 DEG C, sintering, and quenching after sintering to obtain the expanded porous porcelainized aggregate acoustic board. The aggregate acoustic board prepared by the invention has the excellent performances of high porosity, light weight, high compressive strength, good fire resistance and the like, and can simultaneously realize low carbon emission and solid waste resource utilization in the preparation process.

The invention discloses a grating wallboard which comprises a polyester fiber base plate and a plurality of polyester fiber strips, the polyester fiber strips are arranged on the surface of one side of the polyester fiber base plate in parallel at equal intervals, and a leather film covers the upper surface, the left side surface and the right side surface of each polyester fiber strip. The left side end and the right side end of the leather film extend inwards to form a left bent area and a right bent area respectively, and the left bent area and the right bent area cover the left side edge area and the right side edge area of the lower surface of the polyester fiber strip. The lower surface of the polyester fiber strip facing the polyester fiber substrate is positioned in a middle area between the left bending area and the right bending area and is connected with the polyester fiber substrate through an adhesive layer; the density of the polyester fiber strips is larger than that of the polyester fiber base plate. According to the grating wallboard, formaldehyde is avoided, the grating wallboard is more environmentally friendly and light in weight, the moisture resistance is improved, and the structural form stability and the overall strength are improved.

The invention relates to a multilayer special-shaped section sound absorption material and a preparation method thereof. The multilayer special-shaped section sound absorption material comprises a special-shaped layer, a bottom layer and a plurality of supporting assemblies evenly distributed between the special-shaped layer and the bottom layer. The supporting assemblies, the special-shaped layer and the bottom layer define a cavity. The special-shaped layer is of a multi-layer laminated structure, and the multiple layers are independently selected from any one of a linear layer, a circular layer and a pentagram-shaped layer and are different from one another; wherein the cross section of fibers used by the straight-line-shaped layer is straight-line-shaped; the cross section of the fiber used by the circular layer is circular; and the section of the fiber used by the pentagram-shaped layer is pentagram-shaped. When sound waves penetrate through the special-shaped layer, the sound waves can be reflected back and forth and spread among the linear layer, the circular layer and the pentagram-shaped layer of the special-shaped layer, and therefore sound energy can be further consumed, and the multilayer special-shaped section sound absorption material has good sound absorption performance.

The utility model relates to the technical field of floor support plates, and provides a combined type floor support plate which comprises a bearing plate. The punching plate is arranged on the bearing plate, a mounting space is defined by the punching plate and the bearing plate, and the filling piece is arranged in the mounting space. By means of the technical scheme, the problem that in the prior art, an open type floor support plate is poor in fire prevention and sound insulation is solved.

The utility model provides a kind of road noise barrier based on sound-absorbing material, including barrier support assembly and barrier body, barrier support assembly includes the barrier support post of pair arrangement, and the sliding slot upper end of barrier support post is connected with buffer sliding block, and one barrier hanging pole is connected between buffer sliding block, barrier hanging pole is connected with barrier assembly support by hinged link, and barrier assembly support is connected with barrier body by bolt.The utility model in barrier body is converted into heat energy dissipation by the sound hole hole of sound hole board body, and the sound-absorbing micropore on microporous attraction cloth layer is based on micro-perforated plate theory, and the sound-absorbing coefficient is excellent in full frequency band, especially in low frequency part, further improve sound-absorbing effect, significantly improve the sound-absorbing performance of low frequency band by sound-absorbing cotton layer, and the porous structure of sound-absorbing cotton layer effectively insulates internal air convection and heat radiation, significantly reduce heat loss, while large aperture area absorbs and reflects sound wave, effectively reduce noise.

The invention discloses an aluminum sol / carbon nanotube composite flame-retardant polyimide foam sound absorption material and a preparation method thereof. The preparation method comprises the following steps: stirring and mixing aromatic dianhydride, a polar solvent I and small molecular alcohol, and carrying out reflux reaction to obtain a precursor solution; dispersing carbon nanotubes in a polar solvent II, performing ultrasonic dispersion, then adding aluminum sol, and continuing ultrasonic mixing to obtain an aluminum sol / carbon nanotube solution; stirring and mixing a flame retardant, a catalyst, a foam stabilizer and a foaming agent to obtain a compound additive; and mixing polyisocyanate, the precursor solution, the alumina sol / carbon nanotube solution and the compound additive, foaming, and curing at high temperature to obtain the alumina sol / carbon nanotube composite flame-retardant polyimide foam sound absorption material. The polyimide foam sound-absorbing material of the dispersed aluminum sol / carbon nano tube has excellent sound-absorbing and flame-retardant properties, and has a wide application prospect.

The invention provides a low-frequency sound-absorbing nanofiber composite material and a preparation method thereof, and belongs to the technical field of sound-absorbing nanofiber composite materials, and the nanofiber composite sound-absorbing material is formed by compounding liquid spraying nanofibers and kapok pulp. According to the preparation method, the nanofibers are prepared in batches through a liquid jet spinning process, the kapok pulp fibers are blown into the nanofibers through high-speed airflow when the nanofibers are drafted, online compounding of the kapok pulp is achieved through a designed spraying device, and the efficient nanofiber sound-absorbing composite material is prepared. According to the composite sound absorption material, the specific surface area and porosity of the material can be improved, more sound energy absorption paths and more effective sound wave energy loss are provided, so that the sound absorption performance of the sound absorption material is improved, the mass of the material is reduced, and the composite sound absorption material has the characteristics that the low-frequency sound absorption effect is good, the frequency band is wide, and the preparation method is simple and convenient to operate.

The invention discloses a composite broadband ultrathin sound absorption structure, which belongs to the technical field of sound absorption structures and comprises a hollow sound incidence area and a micro-perforated plate arranged on one end face of the sound incidence area. A neck structure is arranged on the outer side of the sound incidence area in a communicating mode, and the neck structure extends outwards in the height range where the sound incidence area is located. The side surface of the neck structure is provided with a sheet type breathable resistive material; a cavity is arranged on the outer side of the sound incidence area, and the neck structure and the cavity form a Helmholtz sound absorption structure. The peak sound absorption coefficient of the structure is still large, but the sound absorption band is wider, the structure is thinner, the application range of the structure is wider, the structure is particularly suitable for application scenes with limited space thickness, and the defects of a traditional resonance sound absorption structure in the aspects of the sound absorption effect and the size are overcome.

The utility model discloses a green building thermal insulation wall structure which comprises a first outer protection plate and a second outer protection plate, a thermal insulation strengthening mechanism is fixed between the first outer protection plate and the second outer protection plate in a positioning mode, and an energy-saving mechanism is installed on one side of the second outer protection plate in a positioning mode. According to the green building thermal insulation wall structure, the overall energy-saving effect is improved through the arranged energy-saving mechanism, the photovoltaic solar panel is used for absorbing a solar light source and converting the solar light source into electric energy, solar energy is used, dependence on traditional energy is reduced, the polyurethane rigid foam thermal insulation layer has the thermal insulation effect and is low in thermal conductivity, and the energy-saving effect is good. The sound insulation board layer has the effects of sound insulation, fire prevention and easy installation and provides good sound insulation so as to improve the living comfort, the heat preservation glass wool layer has good heat insulation and heat preservation performance and good sound absorption performance, the heat preservation effect is further improved, and the phenolic aldehyde foam layer is fireproof, heat-insulated, heat-preservation, energy-saving and capable of enhancing the overall performance of the wall body.

The invention relates to a road paving structure and a construction method thereof, and the road paving structure comprises a concrete base layer, a waterproof layer, a hard asphalt lower surface layer, a first bonding layer and an epoxy modified rubber asphalt surface layer which are sequentially arranged from bottom to top; and the void ratio of the epoxy modified rubber asphalt surface layer is 8-18%. Compared with the traditional SMA-13 pavement, the pavement has the beneficial effects that the noise inside and outside the vehicle is obviously reduced at the running speed of 80km / h, the driving experience is optimized, the stability of the pavement reaches the standard in the service period, and the pavement can be popularized and used.

The application relates to the field of noise reduction technology and discloses a spiral acoustic black hole noise reduction module and a design method thereof, which comprises a shell layer, an acoustic black hole cavity and a neck pipe; the shell layer is used for wrapping the acoustic black hole cavity to form a closed space; the acoustic black hole cavity comprises an acoustic black hole cavity plate curved according to an Archimedes spiral line and a rib plate array; the neck pipe is arranged at the rotation center position of the spiral line track of the acoustic black hole cavity plate, and the neck pipe is a sound wave incidence pipe; the rib plate array comprises a plurality of rib plates arranged in an increasing or decreasing length; one end of each rib plate is fixed to the inner side of the acoustic black hole cavity plate, and the other end is a free end; the rib plates are arranged at equal arc lengths / distances, and the lengths are arranged in a monotonically decreasing or increasing rule to form an acoustic black hole structure. The application realizes the sound absorption effect of ultralow frequency with a small size, reaches a sound absorption peak under specific frequency, and enhances the sound absorption effect of the sound absorption device in a specific frequency band.

The application discloses a sound-absorbing structure for a pipeline, which comprises an upper partition plate, a lower partition plate, a left inclined plate, a right inclined plate and an outer circumferential panel and encloses a columnar cavity with a fan ring cross section; further comprising an intermediate plate, the outer radius of the intermediate plate is smaller than that of the upper partition plate and the lower partition plate, and the columnar cavity is divided into a first cavity and a second cavity which are in communication with each other; the first cavity is formed with a first arc-shaped partition plate, a second arc-shaped partition plate and a third arc-shaped partition plate which are arranged at intervals in the second cavity, the third arc-shaped partition plate is arranged at the inner circumferential surface of the second cavity, the first inlet is formed at the inner circumferential surface of the first cavity; the second inlet is formed between the third arc-shaped partition plate at the inner circumferential surface of the second cavity and the left inclined plate. The sound-absorbing structure for the pipeline is adjusted to realize sound absorption of different frequency noises. Meanwhile, the space utilization rate can be improved, the size can be reduced, and the processing difficulty can be reduced to realize high-efficiency sound absorption of the 50-1000 Hz frequency band.

This invention belongs to the field of acoustic materials technology and discloses a sound-absorbing material and its preparation method. The sound-absorbing material includes a core layer and a surface layer; the core layer comprises a composite material formed by intercalating meltblown ultrafine fibers with hollow elastic short fibers; the surface layer has two layers, which are respectively applied to opposite sides of the core layer, and each surface layer comprises a flash-evaporated nonwoven fabric, forming a three-layer structure with the core layer. In the sound-absorbing material provided by this invention, the waterproof and breathable properties, as well as the good mechanical and protective properties of the flash-evaporated nonwoven fabric, are utilized to improve the performance defects of short-fiber intercalated meltblown nonwoven sound-absorbing cotton, resulting in a sound-absorbing material with advantages such as waterproof and breathable properties, good sound absorption performance, high mechanical properties, and mildew resistance, thus improving the service life of the sound-absorbing material.

The invention relates to a novel lightweight fully enclosed sound barrier for an urban viaduct, and specifically to the field of closed sound barriers, comprising a base, wherein two groups of anti-collision guardrail components are vertically inserted at the top of the base, two groups of variable-section main columns are arranged between the two groups of anti-collision guardrail components, the two groups of variable-section main columns are fixedly inserted at both sides of the top of the anti-collision guardrail components, and the anti-collision guardrail components are located between the two groups of variable-section main columns and have a plurality of side sub-columns inserted at equal intervals. The technical key points are as follows: the anti-collision guardrail components are arranged as a separate guardrail body and a movable vertical plate, a plurality of silicone balls for buffering are arranged between the guardrail body and the movable vertical plate, a plurality of silicone clamping columns are installed on the surface of the movable vertical plate, the plurality of silicone clamping columns are interconnected through silicone pipes, the silicone clamping columns are used to mitigate vibrations caused by collisions of the movable vertical plates, and the silicone pipes are expanded during compression to protect against collisions and buffer.

The present invention relates to the technical field of river and lake sludge treatment, and provides an environmentally friendly microporous sound-absorbing ceramic prepared by using river and lake bottom mud and a preparation method thereof. The process includes mixing river and lake bottom mud, fly ash, diatomaceous earth, expansion agent, dispersant, and gelling agent, adding water to form an initial slurry; ball milling the initial slurry to obtain a premixed liquid; adding a foaming agent to the premixed liquid, stirring once, then adding a foam stabilizer, stirring twice, to obtain a ceramic slurry; injecting the ceramic slurry into a mold, covering the surface of the ceramic slurry in the mold with a non-woven fabric, and standing to form a mold; then removing the non-woven fabric, demolding to obtain a green body; drying and sintering the green body to obtain an environmentally friendly microporous sound-absorbing ceramic. The present invention can avoid the occurrence of green body cracking through process improvements in injection molding and other links, greatly improve the yield rate of material preparation, and improve the production efficiency of sound-absorbing ceramics, and is suitable for the preparation of large-scale porous sound-absorbing ceramics.

The invention discloses an acoustic superstructure and porous material composite sound absorber for fan pipe noise reduction and its preparation method, comprising: cutting glass fiber to a certain length, adding it into a preparation device, melting, centrifugal injection molding, and high-temperature curing, so as to obtain glass fiber sound-absorbing cotton; cutting straw to a certain length, arranging them in a movable unit slot with consistent orientation; melting polylactic acid plastic, evenly applying it to the unit slot and the straw, filling glass fiber sound-absorbing cotton between the straw and the unit slot, cooling and curing to finalize, so as to achieve the effect of effective sound absorption and noise reduction for low-frequency noise emitted by the fan pipe, and because the glass fiber sound-absorbing cotton and corn straw have high plasticity, when a certain amount of compression is performed, the composite material has a high reuse rate.

The invention discloses a noise-reducing multilayer material, a preparation method thereof, a noise-reducing structure containing the noise-reducing multilayer material and a range hood. The noise reduction multilayer material comprises an elastic porous material layer and a nanofiber membrane layer arranged on at least one surface of the elastic porous material layer, and the thickness of the nanofiber membrane layer is smaller than 1 mm. According to the noise reduction multilayer material, the medium-high frequency sound absorption coefficient of the composite superstructure can be remarkably increased under the condition that the structure thickness is basically unchanged, and the noise reduction effect is improved under the condition that a flow field is not affected after implementation.

The utility model relates to the field of damping rubber sheet, specifically disclose a damping rubber sheet for car, including damping rubber sheet main part, damping rubber sheet main part includes from top to bottom sequentially arranged corrosion -resistant protective layer, reinforcing layer, double damping layer, magnetic composite layer, first adhesive layer, double damping layer includes laminated arrangement and close reinforcing layer's upper damping layer, far away reinforcing layer's lower damping layer, the upper damping layer, lower damping layer all are provided with a plurality of sound absorption holes, the porosity of upper damping layer is greater than the porosity of lower damping layer. Double damping layer can carry out graded absorption and processing to the noise of different frequency, and the larger porosity of upper damping layer is favorable to absorb middle high frequency noise, and the smaller porosity of lower damping layer has better absorption effect to low frequency noise, thereby can effectively widen the noise reduction frequency band of this damping rubber sheet, significantly improve the overall noise reduction performance, can effectively reduce various noises in the car, create a quiet and comfortable in-car environment for the driver and passenger.

The present application relates to the technical field of layered products, specifically to a flame-retardant, antibacterial, and sound-insulating composite fiberboard and a preparation method thereof, wherein the flame-retardant, antibacterial, and sound-insulating composite fiberboard is composed of a sound-insulating, flame-retardant layer, a reinforcing layer, an antibacterial, and flame-retardant layer, and a finishing layer in sequence; the sound-insulating, flame-retardant layer is made by hot-melt bonding of sisal fiber, polyester fiber, and collagen fiber, and then adding a first flame retardant to mix; the reinforcing layer is a mesh-like structure made by hot-melt bonding of aramid fiber and bamboo fiber; the antibacterial, flame-retardant layer is made by hot-pressing a mixture of raw materials including bamboo charcoal activated carbon, a second flame retardant, and volcanic rock particles; the finishing layer is a non-woven fabric surface layer; the sound-insulating, flame-retardant layer, the reinforcing layer, the antibacterial, and flame-retardant layer, and the finishing layer are bonded by adding PMMA powder and hot-baking and pressing. The present application realizes the autonomous bonding of the composite fiberboard by cross-linking different functional layers, thereby improving the flame-retardant, antibacterial, and sound-insulating properties of the composite fiberboard, while reducing the formaldehyde content of the composite fiberboard and improving the quality of the living environment.

This invention provides a low-frequency broadband sound-absorbing metamaterial structural unit. The structural unit is a cavity enclosed by multiple walls. Air inlets are distributed on the top plate of the cavity. The internal space of the cavity includes a main chamber, which is composed of at least one secondary chamber arranged in a horizontal plane. Each secondary chamber is divided into two sub-chambers by a partition, and an inclined partition is placed between the two sub-chambers. The top edge of the inclined partition is located on the top surface of the secondary chamber, and through holes are formed on the inclined partition. This extremely simple structural form achieves high-efficiency low-frequency broadband sound absorption.

The invention discloses a polyurethane composite material as well as a preparation method and application thereof, and relates to the technical field of noise reduction. The invention provides a polyurethane composite material. The polyurethane composite material is prepared from the following components in parts by weight: 100 parts of polyether polyol, 50 to 80 parts of diphenylmethane diisocyanate, 1 to 3 parts of simethicone, 30 to 40 parts of glass fiber, 200 to 400 parts of magnetic powder and 3 to 10 parts of deionized water. Wherein the magnetic powder is composed of magnetic powder of four specifications of A, B, C and D, the mesh number of the specification A is D1, and the specification A is the magnetic powder with 500 meshes < D1 < = 1000 meshes; the mesh number of the specification B is D2, and the specification B is magnetic powder of which D2 is greater than 250 meshes and less than or equal to 500 meshes; the mesh number of the specification C is D3, and the specification C is that D3 is more than 150 meshes and less than or equal to 250 meshes; the mesh number of the specification D is D4, and the specification D is that D4 is more than 80 meshes and less than or equal to 150 meshes. According to the prepared polyurethane material, the sound absorption performance of the composite material is further improved.

The invention relates to the technical field of sound barrier plates, in particular to a composite concrete sound barrier plate forming device and a production technology, the composite concrete sound barrier plate forming device comprises a forming integration frame, a forming buckle plate is arranged above the forming integration frame, a concrete plate and a glass wool plate are arranged between the forming integration frame and the forming buckle plate, and foamed aluminum sound absorption plates are arranged on the two sides of the forming buckle plate; pulleys are rotationally connected to the two ends of the top of each forming integration frame, and an assembling groove and an assembling block are arranged at the two ends of the bottom end of each forming integration frame correspondingly and used for assembling and connecting the multiple forming integration frames when the multiple forming integration frames are stacked side by side; the forming device has the beneficial effects that the forming integration frame and the forming buckle plate which are of a C-shaped plate-shaped structure are adopted, and the design of clamping grooves, edge grooves and the like is matched, so that a concrete plate, a glass wool plate and other parts can be easily inserted and fixed, and the operation process is greatly simplified; the glass wool board is used as an important sound absorption material and is ingeniously embedded between the concrete boards, so that the sound absorption performance of the sound barrier board is effectively improved.

The invention discloses a highly efficient sound-absorbing lightweight aggregate foam concrete and a preparation method and application thereof, and belongs to the field of inorganic non-metallic materials. The highly efficient sound-absorbing lightweight aggregate foam concrete comprises: 85-95 parts by weight of sulphur-aluminium-iron low-carbon cementitious material, 5-15 parts by weight of auxiliary cementitious material, 0.6-1.5 parts by weight of functional admixture, 20-60 parts by weight of unburned lightweight aggregate, 0.35-0.45 parts by weight of water, and 0.5-1.5 L of prefabricated foam; the unburned lightweight aggregate comprises, by weight: 40-50 parts of sulphur-aluminium-iron low-carbon cementitious material, 50-60 parts of by-product gypsum, 0.7-1.5 parts of chemical foaming agent, 15-22 parts of water, and 5-8 parts of expanded perlite. The present invention achieves a relatively balanced wide-band sound absorption performance and adjustable sound absorption frequency range by constructing a multi-level multi-scale pore structure of expanded perlite pores + hydrogen peroxide foaming pores + physical foaming pores, and the sound absorption and noise reduction coefficient (NRC) of the material is ≥0.80 and the bulk density is ≤500 kg / m 3 , flexural strength ≥1.5 MPa.

The invention discloses ship glass and a preparation method thereof, and relates to the technical field of ship glass. The ship glass comprises a first glass substrate, a second glass substrate and an aerogel layer, the aerogel layer is fixed between the first glass substrate and the second glass substrate, the first glass substrate is located on the side away from the interior of a ship, and the second glass substrate is located on the side close to the interior of the ship. The aerogel layer is a silica aerogel layer doped with titanium oxide, and the aperture of the aerogel layer is gradually reduced in the direction from the first glass substrate to the second glass substrate. The ship glass provided by the invention has the titanium oxide doped aerogel, and the aerogel has gradient aperture, so that not only can ultraviolet rays be effectively isolated, but also the heat insulation and sound absorption effects of the ship glass can be improved on the basis of ensuring good light transmission performance.

The utility model belongs to sound insulation and noise reduction technical field, especially a kind of sound insulation and noise reduction structure for light rail traffic. The technology includes the baffle of vertical arrangement, the bottom of baffle is horizontally fixed with bottom plate, the bottom of the side of baffle away from track is provided with planting groove for planting climbing plant, and the baffle above planting groove is provided with climbing net for making climbing plant climb. The utility model is planted by climbing plant on baffle, and the sound diffused from the edge and top of baffle is absorbed by climbing plant, the sound diffused from the top and edge of baffle is reduced, and the sound absorption effect of baffle is also increased by climbing plant itself, so as to improve the noise reduction effect of baffle.

The application discloses a multi-environment noise suppression device and method for chassis dynamometer test of an automobile. The device comprises a test bin, a sunken bin is arranged under the ground of the test bin, a dynamometer platform is arranged in the sunken bin, a plurality of sound insulation boards are arranged on the bottom wall of the dynamometer platform, a track is arranged in the sunken bin along the length direction of the sunken bin, a dynamometer device is arranged on the track, the dynamometer device at least comprises a pair of rotating hubs for contacting with tires of an automobile to be tested, a sealing sound insulation assembly is arranged on the dynamometer platform and is in contact with the rotating hubs, and a plurality of movable sound absorption assemblies are arranged on the track at intervals. In the scheme, the dynamometer device is arranged in an underground space, noise radiated to the space above the ground is reduced by using sound insulation of the underground space, the upward diffusion of the noise is blocked by the sound insulation boards, the movable sound absorption assemblies are arranged flexibly near the noise source, the rotating drum and the transmission mechanism are wholly covered in the multilayer sound insulation structure, and the upward propagation path of the noise is cut off.

The invention discloses a simple light underwater sound absorption metamaterial and application, and belongs to the field of sound absorption materials. The sound absorption metamaterial comprises a plurality of basic units arranged periodically, each basic unit comprises an upper structure layer, an external structure and a lower structure layer, and the external structure comprises a hollow circular ring weight reduction structure distributed in the axial direction of the external structure. All the structures are filled with various media. The included angle between the inverted-truncated-cone-shaped upper structure layer generatrix and the upper bottom face is smaller than the included angle between the inverted-truncated-cone-shaped or cylindrical lower structure layer generatrix and the upper bottom face. Acoustic waves are conducted to the upper structural layer, the external structure and the lower structural layer, and the external structure is made of high-strength materials, so that waveform conversion can be induced to promote shear dissipation of the viscoelastic materials, sound energy loss is enhanced, and the sound absorption effect is improved compared with remarkable mismatching of acoustic impedance of viscoelastic materials of the upper structural layer and the lower structural layer. The material can better resist hydrostatic pressure, the preparation process is simple, and the sound absorption effect is ensured.

The invention relates to the technical field of suspended ceiling structures, and discloses a sound insulation and noise reduction suspended ceiling structure which comprises a plurality of splicing modules which are the same in structure and spliced together. Second vacuum silencing bags staggered with the first vacuum silencing bags are evenly fixed to the top of the sound insulation plate, the second vacuum silencing bags are semi-elliptical spherical bags, sound absorption seats with upward openings are assembled among the four adjacent sets of first vacuum silencing bags, each set of sound absorption seats is in a semi-elliptical spherical shape, and the first vacuum silencing bags and the second vacuum silencing bags are arranged in a staggered mode. A semi-elliptical spherical silencing block is assembled in each group of sound absorption seats, so that the variability of the reflection direction of noise is improved, the energy loss of the noise after reflection is increased, the circular silencing grooves can be stretched to be elliptical, and the conduction path and the reflection characteristic of sound waves in the elliptical holes are changed, so that the sound absorption effect is enhanced; when low-frequency noise is generated and vibration is generated, a good sound absorption effect is achieved.