40 results about "Resonant absorption" patented technology

The invention discloses a preparation method of a flexible infrared super-surface absorber based on MDM, and belongs to the field of micro-nano machining patterning. The method comprises the following steps: pretreating a polymer material; depositing a layer of bottom metal film on the pretreated substrate by adopting magnetron sputtering; a metal reflecting layer, a dielectric insulating layer and a metal surface functional layer are sequentially deposited through magnetron sputtering, a periodic nano microstructure is constructed on the surface of a flexible composite film, a nano round pit array is etched in situ on a surface metal layer of an MDM structure by using a femtosecond laser selective etching process, and an MDM laminated structure is formed. According to the invention, stable integration of the MDM structure and the flexible substrate can be realized, and meanwhile, high absorptivity and good flexibility of the device in an infrared band are ensured. The absorber prepared by the invention can generate resonance absorption on incident infrared electromagnetic waves through a surface plasmon and F-P cavity resonance coupling mechanism, and meanwhile, the characteristic size variation is changed through physical excitation, so that effective absorption and frequency regulation of the electromagnetic waves at the infrared band of 3-14 microns are realized.

The invention discloses a method for synthesizing a ZnFe2O4 photocatalyst based on ferromagnetic resonance absorption effect mediation. The synthesis method comprises the following steps: dissolving Zn (NO3) 2.3 H2O and Fe (NO3) 3.9 H2O in deionized water, and stirring to obtain a mixed solution; adding a NaOH solution to adjust the pH value; continuously heating and stirring, filtering after low-power short-time microwave heating, washing with water until the pH value of supernate is 7, and naturally drying; and continuously calcining the dried product, and then carrying out low-power short-time microwave heating to obtain the ZnFe2O4 photocatalyst with the specific surface area of 49.3-50.6 m < 2 > / g, the visible light absorption range of 580 nm and the saturation magnetization of 46.5-47.33 emu / g. The obtained photocatalyst is large in specific surface area, high in visible light absorption capacity, low in photogenerated charge recombination efficiency, easy to separate and recycle, high in photocatalytic capacity and capable of effectively removing norfloxacin in wastewater.

To provide a metasurface structure and gas sensor that can accurately detect targets at low concentrations of 1 ppm or less contained in gas. [Solution] Light in the ultraviolet region is irradiated onto the substrate 2 and the metal part 3 on the substrate 2, and only specific wavelengths are absorbed and reflected by surface plasmon resonance, and the gas to be detected is provided near the metal part 3. The aspect ratio of the gap between adjacent metal parts 3 along the x-axis on the substrate 2 is set to 55 / (300-10) or more and 100 or less. The aspect ratio qy of the gap between adjacent metal parts 3 along the y-axis on the substrate 2 is set to 55 / (800-163) or more and 100 / (300-296) or less. The filling factor of the metal part 3 along the x-axis on the substrate 2 is set to 10 / 300 or more and 0.99 or less. The filling factor of the metal part 3 along the y-axis on the substrate 2 is set to 163 / 800 or more and 296 / 300 or less.

The invention provides a microwave control method and a microwave controller for an electron paramagnetic spectrometer. The microwave control method for the electron paramagnetic spectrometer comprises the following steps: controlling a microwave source to generate a microwave signal for paramagnetic resonance detection; a first power division signal and a second power division signal are obtained through distribution; inputting the first power division signal into a resonant cavity, detecting a reflection signal of the resonant cavity after resonance absorption of the to-be-detected sample to obtain a first detection signal, and performing phase shift on the second power division signal to obtain an orthogonal local oscillation signal; performing frequency mixing on the first detection signal and the local oscillator signal to obtain an I down-conversion signal and a Q down-conversion signal; performing data processing to obtain detection result information; and error analysis is performed and the microwave source is corrected, so that the frequency of the output microwave signal is kept at the first working frequency. By establishing a feedback loop from output to microwave signal input of the microwave source, feedback control of microwave signals is realized, and high-precision microwave control in the electron paramagnetic spectrometer is further realized.

The invention discloses an out-of-band wave-absorbing electromagnetic window based on transverse quasi-cavity resonance, and relates to the technical field of artificial electromagnetic materials. An impedance layer is arranged and forms a series resonance circuit, so that incident electromagnetic waves excite transverse quasi-cavity resonance on metal wires of inductance structure units, absorption of low-frequency-band electromagnetic waves (C wave band) is achieved, and the electromagnetic window has the advantages of being simple in structure, low in cost and high in efficiency. Then, incident and reflected electromagnetic waves excite a surface plasmon polariton (SSPP) mode on the metal grid bars, so that energy is located in gaps of the metal grid bars and the second dielectric substrate, and the second dielectric substrate realizes absorption of high-frequency electromagnetic waves (Ku wave band), namely, compatible synergistic absorption of low-frequency resonance absorption of the impedance layer and high-frequency SSPP mode absorption of the high-frequency wave-absorbing structure is realized; meanwhile, efficient transmission of a middle wave band (X wave band) is achieved through the frequency selection surface on the lowermost layer, and finally absorption and transmission integration of vertical resonance regulation and transverse electromagnetic coupling is achieved under a wide frequency band.

The application discloses molybdenum-doped nano zinc oxide with high visible light photocatalytic performance and a preparation method and application thereof. The molybdenum-doped nano zinc oxide is prepared from 1-octadecene, 1-dodecanol, oleic acid, a zinc source and a molybdenum source through vacuum degassing treatment, uniform stirring under a nitrogen atmosphere, heating to 100-140 DEG C, keeping warm until solid particles are dissolved, heating to 220-250 DEG C, keeping warm for 0.5-1 h of reaction, and cooling, washing and drying. The molybdenum-doped nano zinc oxide produces a local surface plasmon resonance absorption peak in the range of 600-700 nm through molybdenum ion doping, and the nano powder has a diameter of 5-20 nm; and the visible light photocatalytic performance of the zinc oxide material is greatly improved under the condition of visible light.

The utility model discloses a detachable exhaust duct silencer, which relates to the technical field of silencers and comprises a frame plate mechanism, detachable sealing mechanisms are arranged on two sides of the frame plate mechanism, and a silencing resonance mechanism is inserted into the frame plate mechanism. In order to solve the problems that in the prior art, due to the fact that a silencer is prone to being blocked and needs to be replaced and maintained, forked pipes and single connecting pipes are arranged on the two sides of a frame plate mechanism, the airflow speed is reduced, local turbulence noise caused by airflow bias is avoided, a combined noise reduction scheme of source control and tail end treatment is formed, and the noise reduction efficiency is greatly improved by disassembling the corresponding arrangement of a sealing mechanism and a noise elimination resonance mechanism. The two sides of the frame plate mechanism can be opened for maintenance, the micro-perforated cylinder plates form a resonance structure through micro-holes in the plates and cavities formed by separation of the separation insertion plates, the micro-perforated cylinder plates are arranged in a staggered mode, and sound energy is absorbed through resonance of air columns at the small holes.

The invention discloses a microwave irradiation area matching method and a microwave irradiation area matching system, and relates to the technical field of intelligent energy regulation and control. Key parameters such as reflection and transmission power, three-dimensional temperature distribution, blood flow change, tissue moisture content and thickness of a target area are acquired in real time by combining a multi-mode acquisition device, and a comprehensive physiological response parameter set is constructed through multi-source signal fusion and inversion processing; calculating a tissue resonance response coefficient, judging a microwave resonance absorption state, and implementing an energy regulation strategy; a thermal response coupling coefficient is calculated, thermal effect response is evaluated, and an adjustment strategy is given; calculating a microcirculation improvement index and implementing corresponding adjustment; and finally, constructing an AI dynamic energy adjustment model by using a convolutional neural network to realize adaptive optimization of energy output. According to the method, multi-parameter real-time closed-loop regulation and control can be realized, the energy transfer efficiency and the microcirculation improvement effect are improved, and the method has the advantages of high precision, safety and personalized adaptation.

The application discloses a radar-sound compatible absorbing superstructure and a preparation method thereof, and belongs to the technical field of sound-absorbing and wave-absorbing materials.The superstructure is formed by fusing and depositing 3D printing of a wave-absorbing material, has three-dimensional gradient composition and a multistage pore structure, the multistage pore includes micro-pore and macro-pore structure, and the macro-pore structure is a space folding inclined pore.Micro-pores and macro-pores are simultaneously constructed in the superstructure, the composite effect of the micro-pores and the macro-pores is utilized to form resonance absorption peaks at different frequencies, the problem of excessive thickness / volume of a traditional radar-sound compatible absorbing material is solved, different direction incident electromagnetic waves can be fully contacted with the absorber, omnidirectional multistage reflection is realized, the folding multistage inclined pore can extend the propagation path of sound waves and radar waves without increasing the thickness of the structure, multiple reflections are formed in the folding channel, and thus sharp wave dissipation is caused in the channel.

The invention discloses a radar wave absorbing rubber patch with a periodic grid structure and a preparation method of the radar wave absorbing rubber patch, and belongs to the technical field of wave absorbing materials. According to the wave-absorbing rubber patch, a female and male mold structure is formed by rubber three-dimensional periodic structure units with wave-absorbing performance and rubber three-dimensional periodic structure units with wave-transmitting performance, and the planar rubber patch is formed through integral vulcanization. By utilizing the characteristic that the impedance of the wave-transparent structure unit is close to the air impedance, electromagnetic waves efficiently enter the wave-absorbing structure unit, multiple times of reflection, scattering, interference and resonance absorption of the electromagnetic waves are realized through a complex cavity in the wave-absorbing unit, and the problems that a traditional wave-absorbing patch is single in energy loss mode and insufficient in absorption intensity are solved. The wave-absorbing rubber patch has the characteristics of wide wave-absorbing frequency band, high absorption strength, strong designability, good processability, excellent bearing performance and the like, and the preparation process of the wave-absorbing rubber patch is strong in adaptability, easy to control and suitable for the fields of military stealth, civil electromagnetic protection, electromagnetic interference resistance and the like.

The utility model relates to the technical field of injection pumps, and discloses a low-noise injection pump set which comprises a motor, a pump head is fixedly installed on one side of the motor, and an output shaft of the motor is fixedly connected with the input end of the pump head. The protection structure is arranged outside the pump head and used for reducing noise, the multiple sound absorption plates are installed on the inner wall of the cover body, interference channels are formed through the extending parts on the two sides of the sound absorption plates, the uneven interference faces are formed on the inner wall of the cover body, sound waves generated when an impeller impacts liquid can be gradually absorbed by the interference faces, and propagation and diffusion of the sound waves are restrained; the split cover body facilitates later-stage additional installation of the protection structure, meanwhile, the acoustic board and the extension part are conveniently and independently replaced after being aged and damaged, the closed structure of the cover body prevents noise from directly leaking out, gaps of the acoustic board and the interference groove absorb energy through cavity resonance and surface reflection, and the noise reduction effect is achieved. Medium-high frequency noise is absorbed through reflection and cavity resonance.

A method and apparatus for detecting a low altitude unmanned micro-aircraft (UAV) is described. The method includes recording acoustic signals caused by mechanical vibrations of the motor and rotation of the propeller. The method is characterised in that, in addition, the optical signal of the UAV in the range of visible light (0.4... 0.76 [mu] m) and / or infrared light (0.76 [mu] m... 1 mm) is recorded, the occurrence of optical signal parameter modulation caused by these identical mechanical vibrations is detected, and the presence of a correlation of the acoustic and optical signals of the UAV is recorded, the presence of which indicates the detection of the UAV. The device (1) comprises:-a passive acoustic sensor (2),-a passive optical sensor (4), and-a correlator (3), and-an active acoustic sensor (5) adapted to operate at wavelengths at which acoustic waves resonate and scatter on the UAV, with a frequency range of 10... 20 kHz, and-an active radar sensor (6) adapted to operate at wavelengths at which the acoustic waves resonate and scatter on the UAV. The active radar sensor works at the wavelength corresponding to the signal resonance absorption wavelength in the atmosphere, the range is (1mm... 15mm), and the active radar sensor detects the UAV with the flight height of 5m... 50m.

The invention discloses a scanning imaging system based on an exciton resonance absorption principle. The system is composed of a semiconductor sample with exciton resonance absorption characteristics, an excitation light source, a mechanical chopper, an optical microscopic system, a displacement table, a photoelectric detector, a lock-in amplifier and a computer. The excitation light source provides narrow-band light with a specific central wavelength, the narrow-band light is irradiated to a semiconductor material sample with an exciton resonance absorption characteristic through the optical microscopic system or the lens group, and the position of the narrow-band light excitation sample is controlled through the displacement table. The narrow-band light reflected or transmitted by the semiconductor material is incident on the photoelectric detector through the optical microscopic system, and the computer processes the obtained electric signal to obtain a carrier distribution two-dimensional image in the surface of the semiconductor sample. The method has the characteristics and advantages of simple system structure, low cost and carrier dynamics visualization.

The application discloses a kind of based on 3D printing metamaterial mid-infrared gas sensor and preparation method thereof.The application is printed on the periodic arrangement of column arm unit on substrate using 3D printing technology, and metal film is deposited on its surface, to realize the narrow-band resonance absorption of specific wavelength mid-infrared light.The application can be adjusted by the geometric parameter and arrangement mode of column arm unit, and the absorption characteristics of sensor in mid-infrared wave band are optimized, so that it can produce resonance response to the characteristic absorption peak of target gas, thereby significantly improving the sensitivity and selectivity of gas detection.Compared with traditional planar nanostructure, the optical performance of the sensor structure design of the application is greatly improved, and it has the advantages of miniaturization, rapid response, high sensitivity and excellent gas selectivity, and can be widely used in environmental monitoring, industrial emission monitoring and safety detection and other fields.

The application discloses a kind of for low frequency broadband high-efficiency sound absorption metamaterial unit and its superstructure module, and the metamaterial unit includes the metamaterial cavity enclosed by multiple blocks of wall and the acoustic waveguide channel being arranged in the metamaterial cavity, acoustic waveguide channel is provided with impedance high-efficiency modulation sound absorption body, impedance high-efficiency modulation sound absorption body includes high porosity sound absorption medium and impedance modulation channel.The introduction of impedance modulation channel can effectively change the acoustic characteristics of high porosity sound absorption medium, by changing the geometric configuration of impedance modulation channel, can be widely modulated acoustic impedance, while producing resonance absorption peak in low frequency band, so as to significantly improve the sound absorption performance in low frequency band.A plurality of metamaterial units with different low-frequency high-efficiency absorption performance are connected in parallel, and through the coupling effect between the metamaterial units, a metamaterial module with low-frequency broadband high-efficiency sound absorption and noise reduction performance can be formed, thereby realizing low-frequency broadband high-efficiency sound absorption performance.

This invention discloses a mid-to-low frequency ventilation and sound insulation metamaterial comprising two main areas: sound absorption and ventilation. The sound absorption area is divided into inner and outer rings, each composed of multiple circumferentially arranged sound-absorbing functional cavities. Each functional cavity includes a resonant cavity formed by partitions and a perforated cavity formed by micro-perforated plates. The perforations on the plates are positioned according to the centroid of the vertical projection of the functional cavities. The ventilation area is a cylindrical region enclosed by the inner ring functional cavities, forming a complete resonant cavity via a ring-shaped base plate. This material combines the resonant characteristics of a Helmholtz resonator, achieving mid-to-low frequency broadband sound insulation through multiple parallel HR combinations. The hollow tube design ensures ventilation, and the mid-to-low frequency band utilizes a non-local coupling sound absorption mechanism for sound insulation. A 4.6cm thick specimen can block 90% of incident wave energy (TL≥10dB) in the 435~1700Hz range, and customized designs can be achieved simply by adjusting the aperture. The improved design incorporates a connecting small hole in the center of the inner and outer functional cavity partitions to form a connected functional cavity, bridging the gap between resonance absorption peaks and enhancing low-frequency sound absorption. The improved unit can achieve the same sound insulation effect in the range of 385~1700Hz.

The application relates to the field of layered composite materials, and particularly discloses a material plate compatible with electromagnetic waves and underwater acoustic waves, which comprises a composite absorption layer and an underwater acoustic absorption layer; wherein the composite absorption layer comprises an electrically conductive substrate and a plurality of layers of alternately stacked sound absorption material plates and wave absorption functional plates, the wave absorption functional plate is composed of a dielectric substrate and a patterned resistive film; and the underwater acoustic absorption layer is a viscoelastic material matrix embedded with a cavity structure. Wideband resonant absorption and impedance matching of electromagnetic waves are realized through multi-size resistive film patterns, and the sound absorption material plates and the cavity-matrix in the underwater acoustic absorption layer are used in cooperation to preliminarily consume and deeply dissipate underwater acoustic waves. The application improves the impedance mismatching problem of underwater acoustic absorption and electromagnetic absorption, has the advantages of wideband, high efficiency and compact structure, and is suitable for radar and sonar compatible stealth skins of equipment such as ships and cross-medium vehicles.

The utility model provides a pixel structure and an infrared detector, relates to the technical field of infrared detectors, and aims to improve the infrared absorption capability of the detector. The pixel structure comprises bridge arms, bridge piers and a bridge floor. The bridge floor is connected with the piers through the bridge arms. The bridge surface comprises an infrared absorption layer and an enhanced absorption layer above the infrared absorption layer, the enhanced absorption layer comprises a metasurface structure and a conductive structure, the conductive structure is connected with the bridge arms, and the conductive structure is further connected with the infrared absorption layer. According to the pixel structure, the enhanced absorption layer composed of the metasurface structure and the conductive structure is added on the infrared absorption layer, so that the infrared absorption efficiency of the pixel structure can be enhanced. Resonance absorption of infrared radiation of a specific wave band can be achieved by regulating and controlling the surface plasmon effect, and the responsiveness of the pixel structure to an infrared spectrum is remarkably improved. And the preparation of the enhanced absorption layer is highly compatible with the preparation process of the existing pixel, only the pattern of the single-layer mask plate needs to be adjusted, no additional process needs to be added, and the practicability and the mass production potential are improved.

The utility model discloses a shock absorption and sound absorption cotton structure for an automobile, and relates to the technical field of shock absorption and sound absorption cotton, the shock absorption and sound absorption cotton structure comprises an outer top plate, an inner sound absorption mechanism is fixedly connected below the outer top plate, and a plurality of groups of fixed rotating seats are fixedly connected above the inner sound absorption mechanism; through the telescopic synergistic effect of the multiple sets of damping rods and the supporting springs, directional attenuation is conducted on vibration energy perpendicular to the outer top plate, and energy dispersion caused by multi-degree-of-freedom vibration is avoided; a double-side rotating seat, a first damping rod and a second damping rod are matched, a multi-stage dissipation path of vibration energy in the vertical direction is formed, the damping efficiency is remarkably improved, the vibration energy enters the sound absorption cotton layer in a directional mode through the hard dense-hole bottom plate, and high-frequency noise attenuation is achieved; the high-density sponge layer absorbs low and medium frequency sound waves through pore resonance, the aluminum foil layer forms a sound and heat isolation barrier through the dual functions of sound reflection and heat radiation blocking, and finally the integrity of a sound wave gradient attenuation path is guaranteed through supporting of the rubber supporting columns.

A resonant sound absorber according to the present invention is attached to an attachment surface in an inner cavity of a tire. The resonant sound absorber comprises: a resonance box that has an opening and has a hollow part formed on the interior thereof; and a hollow neck part that is inserted into the opening and affixed to the resonance box, and extends into the hollow part.

The application provides a sound absorption structure and device. The sound absorption structure comprises: a body having a sound wave incidence surface; a plurality of partitions, at least part of the partitions being arranged in the body in a first direction parallel to the sound wave incidence surface, and at least part of the partitions being arranged in the body in a second direction parallel to the sound wave incidence surface, the first direction intersecting the second direction; and a plurality of partitions and the body enclosing a plurality of resonance cavities, the resonance cavities being configured to absorb sound waves by resonance; wherein at least one of the resonance cavities is bendable; and when bent, the length of the at least one resonance cavity in the first direction and / or the second direction changes. The above sound absorption structure can better adapt to different curved surfaces by configuring the bendable resonance cavities, thereby saving a large amount of installation space and greatly widening the application scenarios and application range of the sound absorption structure.

The utility model relates to a laminated vibration absorption and isolation trench structure, which comprises a soil retaining and vibration isolation structure and an additional laminated vibration absorption structure, the soil retaining and vibration isolation structure comprises a vertical plate, a toe plate and a heel plate, and the additional laminated vibration absorption structure is positioned on the upper part of the heel plate and on the outer side of the vertical plate and comprises a flexible cushion layer, a rigid restraint layer and an earthing mass body. According to the laminated vibration absorption and isolation trench structure, on one hand, vibration energy of a target controlled body input from the outside is isolated through the soil retaining and vibration isolation structure, and static stability of the vibration isolation trench is guaranteed, and on the other hand, vibration energy of a part of frequency bands in environmental vibration is absorbed through resonance of the additional laminated structure. Energy of the specific frequency band is blocked from being transmitted to the target control body, and the vibration reduction effect of the concerned frequency band is improved.

The application discloses a gold nanorod enhanced photothermal elastic gas detection system and a detection method, which are used for improving the universality of the gas detection system. The system comprises an adjustable laser, a gas cell and a quartz tuning fork. The light receiving area of the quartz tuning fork is arranged at the corresponding position of the modulated laser output by the adjustable laser. The light receiving area is provided with a photoelectric conversion film coating. The photoelectric conversion film coating comprises gold nanorod material deposited on the surface of the quartz tuning fork. The longitudinal localized surface plasmon resonance absorption peak of the gold nanorod material is matched with the absorption wavelength band of the to-be-detected gas. When the modulated laser emitted by the gas cell irradiates the photoelectric conversion film coating, the gold nanorod material enhances the absorption of the modulated laser through the localized surface plasmon resonance effect and converts the modulated laser into heat energy. The heat energy generated by the photoelectric conversion film coating is transmitted to the quartz tuning fork, so that the quartz tuning fork generates thermal elastic deformation and excites the quartz tuning fork to vibrate and output a gas concentration electric signal.

The application belongs to the technical field of wind power generation equipment maintenance, and discloses a deicing system and method for wind power generation blades, which comprises an ice quality monitoring device; the ice quality monitoring device is used for collecting and sending blade ice layer state data of a blade to be deiced at a current time to a control module; a microwave radiation antenna is used for receiving microwave energy excited by a microwave generator and radiating to an ice layer; the control module is used for predicting preset characteristic data of an ice layer on a blade to be deiced at a next time based on the blade ice layer state data of the blade to be deiced at the current time and in combination with meteorological data of a region where the blade to be deiced is located; and is also used for controlling and adjusting the power and frequency of microwave energy generated by the microwave generator according to the preset characteristic data of the ice layer on the blade to be deiced at the next time; the application flexibly adjusts the power and frequency of the microwave energy according to the actual physical state of the ice layer, improves the resonance absorption effect of the microwave energy and the ice layer, and improves the deicing efficiency.

The invention relates to a multispectral plasmonic sensor for chiral molecular barcoding, employing a pixelated array of nanostructured plasmonic units coupled with a photonic cavity. Each pixel is tuned to resonate at distinct mid-infrared (mid-IR) wavelengths, facilitating simultaneous detection of molecular chiral and vibrational properties. The system generates near-perfect resonant absorption, maximizing electric and magnetic field enhancements. When illuminated with circularly polarized light, the sensor produces a chiral near-field with handedness determined by the polarization direction. The interaction between the sensor and chiral molecules is quantified using dissymmetry factors, forming unique chiral barcodes that encode molecular behavior across multiple wavelengths. The sensor enables surface-enhanced infrared absorption (SEIRA) induced surface-enhanced vibrational circular dichroism (SEVCD) measurements, providing comprehensive chiral and vibrational analysis. This approach creates a unique barcode for every chiral active molecule, supporting advanced applications in chemical analysis and molecular identification.

The invention discloses a nano-scale electromagnetic shielding coating and a preparation method thereof, and belongs to the technical field of electromagnetic shielding materials, the coating comprises nano-silver and a nano-scale dielectric material, the nano-scale dielectric material comprises nano-scale barium titanate, the nano-scale dielectric material is a resonance excitant, and the nano-scale dielectric material comprises nano-scale barium titanate. The dielectric confinement field amplifies vibration of free electrons on the surface of the nano-silver and excites the nano-silver to generate surface plasma resonance, the free electrons of the nano-silver absorb energy of electromagnetic waves, and the energy is converted into heat energy through interaction of the electrons and crystal lattices, so that resonance loss of the electromagnetic energy is achieved, and the purpose of shielding the electromagnetic waves is achieved. Compared with the prior art, through the synergistic effect of the nano-silver and the nanoscale dielectric material, the electromagnetic shielding potential of the nano-silver is more fully utilized, electromagnetic waves are reflected, and electromagnetic energy is absorbed through resonance, so that the shielding performance of the coating is remarkably improved, and efficient electromagnetic shielding is realized in a wider frequency band; the method is especially suitable for scenes with strict electromagnetic environment requirements.

The utility model belongs to the technical field of building curtain walls, and particularly relates to a building sound insulation curtain wall structure which comprises a supporting frame, the right end of the supporting frame is fixedly connected with a decoration panel, the inner wall of the supporting frame is fixedly connected with a first sound absorption layer, the first sound absorption layer makes contact with the decoration panel, the inner wall of the supporting frame is fixedly connected with a second sound absorption layer, and the second sound absorption layer makes contact with the decoration panel. The second sound absorption layer makes contact with the first sound absorption layer, the inner wall of the supporting frame is fixedly connected with a noise reduction layer, the noise reduction layer makes contact with the second sound absorption layer, the outer side of the noise reduction layer is fixedly sleeved with a blocking layer, and the blocking layer is fixedly connected with the supporting frame. Through the arrangement of the first sound absorption layer and the second sound absorption layer, sound wave resonance can be destroyed, broadband noise can be absorbed, under the action of the noise reduction layer, structural vibration sound transmission is restrained, under the action of the blocking layer, the good sound insulation sealing characteristic can be formed, transmission of remaining sound waves can be blocked, and therefore the good sound insulation effect of the building curtain wall can be guaranteed.

The invention discloses a multiband microwave metasurface absorber, and relates to the technical field of microwave functional devices, the multiband microwave metasurface absorber comprises a plurality of unit structures which are periodically arranged, and each unit structure comprises a metal grounding layer, an intermediate dielectric layer and a top metal resonance structure which are arranged from bottom to top; the top metal resonant structure comprises a peripheral closed ring and a metal cross-shaped structure arranged in the center of the peripheral closed ring, and the peripheral closed ring is formed by connecting four square metal rings end to end; the size of each square metal ring and the size of the metal cross-shaped structure are configured to enable the absorber to excite at least two resonance absorption peaks with the quality factors larger than 400 in the microwave frequency band of 8 GHz to 20 GHz. The dual requirements of multi-band coverage and high-frequency selectivity are met at the same time.

Disclosed are systems and devices for absorbing flexural waves. In one example, a pair of scatterers for absorbing a flexural wave acting on a structure includes a monopole scatterer and a dipole scatterer configured to be mounted to the structure at the same location.

The application relates to the field of building materials, in particular to a graphene modified phenolic foam sound insulation board and a preparation method thereof. The graphene modified phenolic foam sound insulation board comprises an outer layer and a phenolic foam layer arranged between two outer layers, and the raw materials of the phenolic foam layer comprise phenolic resin, an emulsifier, graphene, a foaming agent and a curing agent; the mass ratio of the phenolic resin, the emulsifier, the graphene, the foaming agent and the curing agent is 1:(0.08-0.2):(0.02-0.06):(0.03-0.09):(0.1-0.3). The phenolic foam layer prepared from phenolic foam and graphene sheets can form resonance absorption with the sound wave vibration of a floor, so that the effect of noise reduction and sound insulation is achieved. The phenolic foam board with added graphene has high structural strength and good fireproof performance, and has great practical application value in the field of building sound insulation.