119 results about "Multiple resonance" patented technology

The invention belongs to the technical field of OLEDs, and provides a polycyclic compound containing triphenyl silicon and a polyalkyl substituent group and an organic electroluminescent device containing the polycyclic compound. The structural general formula of the polycyclic compound is as shown in formula I in the specification. Benzofuran with higher electronegativity is introduced to a ring structure composed of nitrogen atoms and boron atoms, triphenyl silicon is introduced to the para-position of boron, and the synergistic effect of benzofuran and triphenyl silicon can significantly enhance the multiple resonance of a light-emitting core and reduce vibration relaxation. Due to simultaneous use of the benzofuran and the triphenyl silicon, the problems of vibration relaxation increase, spectrum widening and the like caused by introduction of the polyalkyl substituent are remarkably improved, the luminous efficiency of the material is remarkably improved, and the color purity is improved, so that the requirement of BT.2020 wide color gamut display standard on a luminescent spectrum is met. I

According to the cluster sound absorption structure for realizing low-frequency broadband sound absorption through multi-resonance coupling, through the multi-resonance coupling among different resonance units in a resonance unit group, between the resonance unit group and a hole pipe embedded plate above and among different coupling resonance clusters, broadband sound absorption can be realized by using a small number of units, and the structure is lighter, thinner, more compact and more flexible. The sound absorption bandwidth is wider, and the sound absorption performance and the modulation efficiency are remarkably improved.

The present disclosure relates to a kind of direct current transformer, direct current transformer includes: transformer circuit, inverter circuit, rectifier circuit and resonance circuit;The direct current side of inverter circuit is connected with direct current input port, the alternating current side of inverter circuit is connected with the primary side of transformer circuit;The alternating current side of rectifier circuit is connected with the secondary side of transformer circuit, the direct current side of rectifier circuit is connected with direct current output port;Resonance circuit includes multiple resonance modules, the alternating current side of inverter circuit is connected with the alternating current side of rectifier circuit through multiple resonance modules and transformer circuit;Resonance module includes first capacitor, resonance module is used to control the input or cut-out of first capacitor.The present disclosure can simulate the voltage outputted when direct current transformer adopts different capacitance resonant capacitor, so as to ensure that direct current transformer does not need to set resonant capacitor, can satisfy the realization condition of resonant soft switching in different working condition scene, and then make the switching device in inverter circuit and rectifier circuit can realize soft switching.

The application relates to the technical field of elastic wave metamaterials, in particular to an elastic wave strong localization plate beam structure based on gradient coupling. The structure comprises multiple resonance units, a stacking structure and a truncated defect structure; the resonance units are sequentially arranged along a first direction to form scale coupling chains, and the coupling stiffness between adjacent resonance units monotonously changes along the direction according to a geometric scale law; the stacking structure is formed by stacking multiple scale coupling chains along a second direction; the truncated defect structure is located at the right end of the middle layer of the stacking structure, and a local vacancy is formed by removing a resonance unit or a connecting plate at the end of the middle layer, which is used for inducing an enhanced localized state. The gradient coupling mechanism is adopted, the wave function space redistribution effect generated by the geometric scale law is utilized, the elastic wave energy shows stronger localization characteristics at the defect, and the localization degree is significantly better than that of a traditional SSH model. Through the synergistic effect of the gradient coupling and the dislocation-induced defect state, efficient localization enhancement of the elastic wave energy is realized, and the application is suitable for the fields of vibration energy collection, high-sensitivity sensing and elastic wave signal processing.

The present invention relates to a compound of the general formula, belonging to the technical field of organic electroluminescence, and particularly to a multi-resonance organic compound. The compound has a structure of the following formula: #imgabs0# The electroluminescence spectrum of an OLED device prepared using the compound of the present invention has a narrow half-maximum width, showing a significant multi-resonance effect. The device also has the advantages of low starting voltage, high luminous efficiency and long life, showing good application prospects.

The invention discloses a control method of a fuel cell power system integrated with online impedance spectroscopy measurement, which belongs to the technical field of fuel cell systems, and comprises the following steps: constructing a mathematical model of the fuel cell power system; designing a closed-loop control strategy and an electrochemical impedance spectroscopy measurement strategy of the fuel cell power system; designing an improved active anti-disturbance controller based on multi-resonance control; a multi-stack system electrochemical impedance spectrum disturbance self-cancellation strategy is introduced, and the design process of the fuel cell power system bus voltage control method based on multi-resonance control is achieved. By adopting the control method of the fuel cell power system integrated with impedance spectrum online measurement, the mutual exclusion limitation of online monitoring and voltage stability is broken through, full-band impedance spectrum continuous acquisition is realized under the condition of continuous normal operation of the system, the bus voltage quality is remarkably improved, and the system reliability is improved. And a key technical support is provided for real-time health diagnosis and active life management of the fuel cell power system.

The invention relates to an aerosol optical tweezer formant track identification method and system based on clustering analysis, belongs to the technical field of spectrum formant identification, and solves the problems that multiple formant tracks are difficult to accurately, completely and automatically identify during aerosol optical tweezer spectrum data analysis in the prior art, and the identification accuracy is high. And the subsequent physical parameter inversion precision is influenced. The method comprises the following steps: acquiring multi-frame aerosol spectral data, extracting candidate formants, and constructing a time-peak position data set; according to the time-peak data set, determining an anchoring trajectory by using a dynamic trajectory tracking algorithm; calculating a relative wavelength difference value corresponding to each candidate formant based on the anchoring trajectory; performing clustering analysis on all relative wavelength differences, and determining candidate formant trajectories; a formant trajectory is determined based on the anchoring trajectory and the candidate formant trajectory. The method achieves the automatic and high-precision recognition and reconstruction of a plurality of formant tracks from the complex noisy spectrum data based on the stable physical constraint of the relative distance between formants.

The invention belongs to the technical field of organic electroluminescent materials, and particularly relates to a boron-nitrogen compound with a naphtho-carbazole structure and an organic electroluminescent device.According to the boron-nitrogen compound with the naphtho-carbazole structure, on the basis of multiple resonance nuclei of boron and nitrogen, novel conjugate extension is constructed, and the structure of the boron-nitrogen compound with the naphtho-carbazole structure is improved; the whole conjugation degree of the structure is increased, so that the structure has a relatively strong rigid conjugation skeleton, the non-radiative transition of excited state energy can be reduced, the relaxation of the excited state structure is inhibited, and the fluorescence quantum efficiency is improved; more importantly, due to the introduced naphtho-carbazole unit, the organic electroluminescent material has better electron and hole double injection capability, so that a host material and a sensitizer material can be better matched, and an OLED device prepared from the organic electroluminescent material has lower driving voltage, higher current efficiency and longer service life.

The application discloses an organic light-emitting material with chiral and narrow-band emission performance, a preparation method and application thereof, and the core is that multiple resonance structures can effectively inhibit the vibration coupling between S1-S0 transition and excited state structure relaxation, form significant narrow-band emission, and simultaneously utilize the axial chirality characteristics of BINOL, utilize a chiral disturbance strategy to form circularly polarized luminescence. The application further provides a preparation method of the material, wherein compound B is obtained by reacting compound C with compound D, and the organic light-emitting material is obtained by reacting compound A with compound B. The material has the characteristics of thermal activated delayed fluorescence induced by multiple resonance effect, and simultaneously has the characteristics of circularly polarized luminescence, and can be applied to the fields of 3D display, molecular probe, spin information, optical data storage and processing and optoelectronic devices, and the like. The synthesis process is simple, raw materials are widely sourced and inexpensive, and the material is suitable for wide application.

The invention provides an IFA-based spurious coupling multi-band antenna and communication equipment. The IFA-based spurious coupling multi-band antenna comprises a base material and an antenna structure, the base material is provided with a feeding point, an antenna foot and a parasitic foot. The antenna structure comprises a connecting arm, a first radiation arm, a second radiation arm and a third radiation arm, wherein the connecting arm, the first radiation arm, the second radiation arm and the third radiation arm are all arranged on a base material; the connecting arm comprises a first connecting part and a second connecting part which are connected with each other. Compared with the prior art, the IFA-based parasitic coupling multi-frequency-band antenna has the advantages that through the multiple radiation arms and the two gaps, the antenna generates multiple resonances, the working frequency band is widened, the antenna efficiency is better, the low-frequency, intermediate-frequency and high-frequency working frequency bands can be covered, and multi-frequency-band full coverage is achieved; under the condition of not increasing the occupied internal space of the communication equipment, the working frequency band is wider, the space occupied by the antenna is very small, and the cost is reduced.

A multi-band antenna has a feed point, a grounding location, a first portion for low band operation, a second portion for low band operation, and one or more portions for high band operation. The ground reference of the feed point for the multi-band antenna is connected to a separate object that may provide a base for the multi-band antenna. The feed point of the multi-band antenna may be spaced above the base and have a space between the feed point and a location for the ground point. The low band portion has multiple resonances that are often odd multiples of the lowest resonant response. The portions that resonant most dominantly in the high band often have multiple resonances that are even multiples of the lowest high band resonance. The multi-band antenna has resonances spaced closely enough to appear to be a wide band antenna above the fundamental high band resonance.

The application provides a luminescent material containing a cyclobutadiene structure, a preparation method and application, and relates to the technical field of organic electroluminescent materials.The luminescent material containing a cyclobutadiene provided by the application is fused to a binary nitrogen-containing fused heterocyclic skeleton by using anti-aromatic cyclobutadiene, the anti-aromatic special electronic structure and high ring tension of the anti-aromatic cyclobutadiene are utilized to inhibit excited state vibration relaxation and realize narrow-band luminescence.By introducing a steric hindrance effect group, the aggregation-induced fluorescence quenching phenomenon between luminescent mother nuclei is weakened, and the fluorescence quantum yield is improved.Different from the current mainstream multiple resonance mechanism, the narrow-spectrum luminescent molecule design provided by the application does not need to depend on the construction of B / N-hetero-fused rings, and the molecular structure can be simplified to realize full-color super-narrow-band luminescence.The application is applied to an organic electroluminescent device, and can realize an electroluminescent spectrum with a super-narrow full width at half maximum and high device efficiency, and provides a better solution for super-high-definition organic light-emitting diode display technology.

The invention relates to the technical field of optics, and discloses a broadband circular polarization terahertz source and application thereof, and the broadband circular polarization terahertz source comprises a free electron beam moving along a predetermined direction and a stacked bianisotropic metasurface located above the free electron beam; wherein the stacked bianisotropic metasurface comprises at least two layers of metal gratings which form a stacked structure; the at least one dielectric plate is used for separating the metal grating; wherein the number of layers of the dielectric plate is one less than that of the metal grating; and the metal grating and the dielectric plate form a periodic structure together, and are used for coupling evanescent wave energy of the free electron beam into multiple resonant modes so as to excite broadband circular polarization terahertz radiation. According to the technical scheme provided by the invention, the tunable and compact terahertz source with high power output can be realized.

Embodiments of the present application provide an electronic device, which includes an antenna using a part of a conductive frame as a radiator, and can produce multiple resonance frequency bands while reducing the opening of the frame gap, so as to meet the communication needs of the electronic device. The electronic device includes a ground plate, a conductive frame and an antenna. The frame has a first position and a second position, the frame is grounded at the first position, the second position is provided with a gap, and the first frame between the first position and the second position serves as a radiator of the antenna. The first frame includes a first grounding point, a first feeding point and a second feeding point, the first feeding point is located between the first grounding point and the first position, the second feeding point is located between the first grounding point and the second position, and the length L1 of the frame between the first position and the first grounding point and the length L2 of the frame between the second position and the first grounding point satisfy: 1.8≤L1 / L2≤2.2.

The present invention discloses a fan-shaped microstrip line array structure, circuit, and design method, wherein the fan-shaped microstrip line array structure includes: a main fan-shaped microstrip line for providing two first resonance points; two groups of auxiliary fan-shaped microstrip lines, the two groups of auxiliary fan-shaped microstrip lines have the same structure and are symmetrically arranged on both sides of the main fan-shaped microstrip line, and the auxiliary fan-shaped microstrip lines are used to provide multiple second resonance points; the arcs of the main fan-shaped microstrip line and the auxiliary fan-shaped microstrip line are both designed in a shape similar to a sine function; the frequencies of the two first resonance points and the frequencies of the multiple second resonance points are respectively distributed on both sides of a preset center frequency; the sum of the angular radians of the main fan-shaped microstrip line and the angular radians of the two groups of auxiliary fan-shaped microstrip lines is less than 180°. The present invention controls the resonance frequency of the fan-shaped microstrip line structure, and then constructs a fan-shaped microstrip line array unit to form a broadband circuit structure with multiple resonance frequency points to meet the design requirements of a broadband RF bias circuit. The present invention can be widely used in RF front-end systems.

The embodiments of the present application disclose a method, device, and medium for detecting the moisture content of insulating cardboard. The insertion loss characteristics corresponding to the microstrip ring resonator device are obtained through a network analyzer; when the insulating cardboard to be detected is a single layer, the average resonant frequency is obtained based on the information of multiple resonance points in the insertion loss characteristics; the moisture content of the single layer of insulating cardboard to be detected is determined based on the average resonant frequency and a preset moisture content evaluation function; when the insulating cardboard to be detected is two or more layers, the dielectric constant and dielectric loss tangent corresponding to the insulating cardboard to be detected are obtained through a preset microstrip ring resonator dielectric response calculation model and insertion loss characteristics; the dielectric constant and dielectric loss tangent are input into a preset moisture content prediction model to obtain the moisture content corresponding to the two or more layers of insulating cardboard to be detected. Through the above method, the efficiency of insulating cardboard moisture content detection is improved.

The application provides a piezoelectric vibration energy collection device with a Z-shaped beam structure, which comprises a piezoelectric energy collection circuit composed of multiple straight beams and piezoelectric layers, and the multiple straight beams in the piezoelectric energy collection circuit are connected in a head-to-tail mode through a wheel disc corner structure, wherein one end of the first straight beam is a fixed end, and the tail end of the last straight beam is a free end. The technical problem of single energy collection frequency band and direction in the prior art is solved. When one end of the Z-shaped beam structure is excited by a vibration source, the straight beams are bent and deformed, the piezoelectric layers are bent and deformed, and thus vibration energy is converted into electric energy. The structure of the application is composed of multiple beams and multiple piezoelectric layers, so that the modal frequency of resonance is concentrated, energy collection under multiple resonance frequencies is realized, and the energy collection efficiency is effectively improved.

The invention discloses a multi-band geomagnetic elastic sheet antenna, which comprises a feed network and a radiation network, and is characterized in that the feed network is used for feeding an external electric signal into the radiation network to enable the radiation network to generate electromagnetic waves to radiate to a free space, and is also used for transmitting a current signal output to the feed network by the radiation network to a rear-end receiving circuit; the radiation network comprises two layers of metal copper sheet structures forming a layered composite structure, and the two layers of metal copper sheet structures respectively realize required electromagnetic characteristics by slotting a metal copper sheet to guide a current distribution path on the metal copper sheet, so that different parts of the two layers of metal copper sheet structures generate resonance at a preset frequency point; the two layers of metal copper sheet structures form a multi-resonance mode and generate a plurality of resonance points; the advantages are that communication can be realized in a plurality of frequency bands, different frequency band requirements of a plurality of operators are compatible, and complexity, cost and size of Internet of Things equipment are reduced.

The invention provides a fused heterocyclic compound, an organic electroluminescent device and display or lighting equipment, and relates to the field of organic photoelectric materials. A multiple resonance structure is introduced, high oscillator intensity, narrow emission spectrum width and high fluorescence quantum yield in the light emitting process are achieved, and the light emitting efficiency and color purity of the device are effectively improved. Meanwhile, the introduction of a spiro skeleton significantly improves the spatial rigidity and configuration stability of molecules, reduces the conformational change in an excited state, and reduces the non-radiative transition rate, thereby enhancing the thermal stability and light stability of the device in the operation process, and prolonging the service life of the device. In addition, through multi-dimensional molecular regulation strategies of expanding a pi conjugated system (such as introducing an aromatic ring, a fused fragment or connecting an expansion unit), regulating peripheral substituents (such as electrical regulation, steric hindrance control, intramolecular hydrogen bond construction and the like) and the like, the molecular skeleton type and electronic structure diversity of the fused heterocyclic ring material are further enriched.

The invention relates to an organic compound with the following general formula and an organic electroluminescent device containing the compound. According to the compound disclosed by the invention, a multi-resonance structure is introduced into a parent nucleus indolocarbazole structure, so that narrow-band emission is maintained while light color is adjusted. When the organic compound provided by the invention is used as a luminescent material in an OLED (Organic Light Emitting Diode) device prepared by evaporation, spraying, printing and the like, the organic compound shows good effects of higher external quantum efficiency and longer service life of the device.

The invention relates to the technical field of fan bearing fault diagnosis, in particular to a fan bearing fault online detection method and system, which adopts a weighted combination envelope spectrum technology, quantifies the correlation between fault features and resonance frequency bands through two-dimensional spectrum coherence, and adaptively distributes weights in combination with a frequency domain signal-to-noise ratio. The fault information of multiple resonance frequency bands is aggregated and enhanced, the attenuation influence in the signal transmission process is effectively counteracted, and the problem that signal attenuation distortion is caused due to the fact that enclosure magnetic attraction installation is needed under the limitation of the fan structure size is solved. An order tracking and constant angle increment sampling technology is introduced, a corresponding relation between a vibration signal and a bearing rotation angle is established, a time domain signal is converted into an angular domain signal, a fault characteristic frequency and a rotation speed are decoupled, and it is ensured that theoretical fault frequencies of parts such as an inner ring, an outer ring and a roller are accurately matched with a detection result. Compared with fixed frequency domain analysis of a traditional acceleration enveloping method, the method has the advantage that misjudgment caused by frequency deviation is effectively avoided.

The invention discloses a dicarbazole axially chiral fused ring compound and an organic electroluminescent device thereof, the organic compound has a structure as shown in a general formula I. A 3, 3 '-dicarbazole structural unit is used as a chiral center, a steric hindrance group is introduced to an ortho-position, and the dicarbazole axially chiral fused ring compound has a rigid and stable axially chiral structure, so that chiral induction is enhanced; one or two multi-resonance units are connected to a carbazole amino group, and a highest occupied molecular orbital (HOMO) and a lowest unoccupied molecular orbital (LUMO) are induced to be positioned on different atoms through a multi-resonance effect, so that the bonding / anti-bonding characteristic between the atoms is weakened; the change of electron density between atoms generated by radiative transition from the lowest excited state to the ground state is greatly reduced, so that telescopic vibration is reduced, and narrow spectrum emission is effectively realized; according to the present invention, with the application of the chiral-induced spin selectivity effect in the OLED light-emitting layer, the high EQE and the high circular polarization electroluminescent factor of the corresponding circular polarization electroluminescent OLED can be achieved on the basis of the chiral-induced spin selectivity effect. # imgabs0 #

The application discloses a kind of microstrip low-pass filters, including dielectric substrate;Microstrip transmission line, microstrip transmission line is located on the first surface of dielectric substrate;Multiple resonance units, resonance unit is etched on the second surface of dielectric substrate, the second surface is opposite surface with the first surface, multiple resonance units are arranged in logarithmic periodic array on dielectric substrate, and a clamping angle is formed at the vertex of adjacent two resonance units in sawtooth shape.The present application adopts logarithmic periodic sawtooth-shaped defect ground structure, and is arranged as resonance unit on dielectric substrate to form microstrip low-pass filter, by setting the resonance unit of logarithmic periodic array arrangement in sawtooth shape, so that the insertion loss of filter in passband is low, and the filter has the characteristics of high performance, wide stopband, good return loss and low insertion loss, etc.

The application belongs to the technical field of organic electroluminescent materials, and particularly relates to a multiple resonance thermally activated delayed fluorescence compound, and simultaneously relates to a thermally activated delayed fluorescence material containing the compound, an organic electroluminescent device, and application of the compound, the material and the device in the field of display and illumination. The multiple resonance thermally activated delayed fluorescence compound provided by the application takes a naphthoindolocarbazole fused ring unit as a strong donor, takes a B atom as a core electron-withdrawing unit, constructs a rigid MR conjugated skeleton with N-B alternately arranged, effectively reduces the optical band gap of the material through the strong electron-donating ability of the fused ring donor, and realizes red light band emission. Meanwhile, based on the multiple resonance effect, narrow-band red light emission is realized, and the color purity is excellent, which can fully meet the stringent requirements of the red light color gamut of the ultra-high-definition display BT.2020 standard.

The present invention discloses a helical chiral thermal multiple resonance activated delayed luminescent material with narrow peak width emission, and its preparation method and application. The structural formula of the helical chiral multiple resonance thermally activated delayed luminescent material is shown in Formulas P1-P4 and M1-M4. The helical chiral multiple resonance thermally activated delayed luminescent material of the present invention can be used to prepare organic light-emitting diode devices, specifically as the light-emitting layer material of the device. The synthesis method of the CP-OLED light-emitting layer material based on the helical chiral helicene molecular skeleton of the present invention is simple, the product yield is high, and it can be prepared on a large scale; the organic film formed by the CP-OLED light-emitting layer material based on the helical chiral helicene molecular skeleton of the present invention has high surface smoothness, anti-oxidation and reduction properties, and high luminescence efficiency, and can be used as the light-emitting layer of an organic light-emitting diode. The organic light-emitting diode with an organic thin film layer formed by the CP-OLED light-emitting layer material based on the helical chiral helicene molecular skeleton as the light-emitting layer has the advantages of high efficiency, low driving voltage, high brightness and long life.

The present application relates to a kind of compound and its application, and organic electroluminescent device comprising the compound, the compound has the following structure, wherein, Z1 and Z2 are not connected, connected by single bond or connected by chemical bond to form ring A, Z3 and Z4 are not connected, connected by single bond or connected by chemical bond to form ring B, the ring A, ring B each independently selected from one of unsubstituted or R' substituted C6-C60 aryl, unsubstituted or R' substituted C3-C60 heteroaryl, R 11 Single substituent represents the maximum allowable number of substituent groups. The device prepared by using the compound of the present application can achieve higher external quantum efficiency, lower turn-on voltage, narrower half-peak width of red light emission and stable device performance. The present application will continue to promote the development of future high light efficiency, high stability, full light color multiple resonance materials and devices.

The invention relates to a dual-mode acoustic wave filter and filtering device based on surface acoustic waves, the dual-mode acoustic wave filter comprises reflectors and a plurality of IDTs arranged between the reflectors, and each IDT is arranged along the propagation direction of the surface acoustic waves; each IDT comprises a plurality of spacing intervals, and each spacing interval is provided with interdigitals which are arranged along the propagation direction of the surface acoustic wave and are sequentially connected end to end; wherein each IDT comprises a main interval area and a plurality of interval adjusting areas, the intervals of the interdigitals in the main interval area are consistent, the intervals of the adjacent interdigitals in each interval adjusting area monotonically change in the direction away from the main interval area in the form of a third power function, and the variation amplitudes of the intervals of the adjacent interdigitals in different interval adjusting areas are different. By adjusting the distance between the interdigitals one by one, the design freedom degree is remarkably improved, multiple resonance modes are constructed in a passband, the bandwidth expansion capability is improved, the insertion loss is reduced, the tuning freedom degree of the device is enhanced, the device can adapt to different use scenes, and the application range is widened.

The application discloses a sound absorption device and a noise reduction equipment, and relates to the technical field of sound absorption, so as to realize effective sound absorption of each resonance sound absorption point in the frequency band range from low frequency to high frequency, realize effective sound absorption of multiple resonance frequencies, reduce sound absorption fault and make the sound absorption effect have wide frequency. The sound absorption device comprises a perforated plate and a sound absorption back cavity. The sound absorption back cavity has an opening, the perforated plate is arranged at the opening, the aperture of the perforated plate is less than 0.1 mm, and the sound absorption back cavity has a plurality of resonance cavities in communication with the opening. The noise reduction equipment comprises the sound absorption device. The sound absorption device provided by the application is used in noise reduction.

The application discloses a double-wideband substrate integrated waveguide back cavity slot antenna, which comprises a circular dielectric substrate, the upper layer and the lower layer of the dielectric substrate are respectively covered with a first metal layer and a second metal layer; the outer ring of an antenna unit is provided with a plurality of metalized through holes, so that the antenna unit forms a substrate integrated waveguide structure; the center of the first metal layer and the second metal layer is provided with a feed hole for a feed probe; a plurality of metalized short-circuit through holes are formed on the first metal layer with the feed hole as the center and the circumference; a plurality of slits with different shapes are formed on the first metal layer, and the metalized short-circuit through holes are located between the slits. The application can significantly improve the bandwidth of the antenna by fusing multiple resonance modes of the substrate integrated waveguide, and can improve the antenna gain while obtaining the wideband performance by optimizing the structure of the radiation slot of the substrate integrated waveguide back cavity slot antenna.

The utility model discloses an air guide ring, a panel assembly, an air conditioner outdoor unit and an air conditioner, and relates to the technical field of air conditioners, the air guide ring comprises a first shell part and a second shell part, the first shell part comprises an air duct wall, the air duct wall defines an air duct, and the air duct wall is provided with a plurality of communicating holes; the second shell part is arranged on the first shell part, a plurality of resonant cavities are defined by the second shell part and the first shell part, the resonant cavities are located on the side, away from the air duct, of the air duct wall, and one resonant cavity communicates with the air duct through at least one communicating hole. According to the technical scheme, the noise reduction and sound absorption capacity of the air guide ring can be improved.