No-wash bioassays based on nanoparticles are used widely in biochemical procedures because of their responsive sensing and no need forwashing processes.Essential for no-wash biosensing are the interactions between nan...No-wash bioassays based on nanoparticles are used widely in biochemical procedures because of their responsive sensing and no need forwashing processes.Essential for no-wash biosensing are the interactions between nanoparticles and biomolecules,but it is challenging toachieve controlled bioconjugation of molecules on nanomaterials.Reported here is a way to actively improve nanoparticle-based no-washbioassays by enhancing the binding between biomolecules and gold nanoparticles via acoustic streaming generated by a gigahertz piezoelectricnanoelectromechanical resonator.Tunable micro-vortices are generated at the device-liquid interface,thereby accelerating the internalcirculating flow of the solution,bypassing the diffusion limitation,and thus improving the binding between the biomolecules and goldnanoparticles.Combined with fluorescence quenching,an enhanced and ultrafast no-wash biosensing assay is realized for specific proteins.The sensing method presented here is a versatile tool for different types of biomolecule detection with high efficiency and simplicity.展开更多
Accurate detection of dimethyl methylphosphonate(DMMP),a simulant for chemical warfare agents,is vital for both public safety and military defense.However,conventional detection methods suffer from low selectivity,owi...Accurate detection of dimethyl methylphosphonate(DMMP),a simulant for chemical warfare agents,is vital for both public safety and military defense.However,conventional detection methods suffer from low selectivity,owing to interference from structurally similar compounds.In this study,we present a highly sensitive and selective gas sensor utilizing a solid-mounted film bulk acoustic resonator based on carbon nanotubes functionalized with hexafluoroisopropanol(HFiP)to enhance DMMP detection.This approach leverages the strong hydrogen bonding between HFiP and DMMP molecules to significantly improve the sensor’s adsorption capacity and selectivity.To further refine selectivity and at the same time solve the cross-sensitivity problem of sensitive membranes,we introduce a virtual sensor array design,generated by modulating the input power to the resonator,which enables the sensor to operate in multiple response modes across varying vibrational amplitudes.These multimodal responses are subjected to linear discriminant analysis,allowing precise differentiation of DMMP from other volatile organic compounds such as tributyl phosphate and dimethyl phthalate.Our results demonstrate superior performance in terms of both sensitivity and selectivity,offering a robust solution for detecting low-concentration DMMP in complex environments.展开更多
Optical three-dimensional(3D)measurement is a critical tool in micro-nano manufacturing,the automotive industry,and medical technology due to its nondestructive nature,high precision,and sensitivity.However,passive li...Optical three-dimensional(3D)measurement is a critical tool in micro-nano manufacturing,the automotive industry,and medical technology due to its nondestructive nature,high precision,and sensitivity.However,passive light field system still requires a refractive primary lens to collect light of the scene,and structured light can not work well with the highly refractive object.Meta-optics,known for being lightweight,compact,and easily integrable,has enabled advancements in passive metalens-array light fields and active structured light techniques.Here,we propose and experimentally validate a novel 3D measurement metasystem.It features a transmitting metasurface generating chromatic line focuses as depth markers and a symmetrically arranged receiving metasurface collecting depth-dependent spectral responses.A lightweight,physically interpretable algorithm processes these data to yield high-precision depth information efficiently.Experiments on metallic and wafer materials demonstrate a depth accuracy of±20μm and lateral accuracy of±10μm.This single-layer optical metasystem,characterized by simplicity,micro-level accuracy,easy installation and scalability,shows potential for diverse applications,including process control,surface morphology analysis,and production measurement.展开更多
The effect of the modification of an alumina support with chloride on the structure and the catalytic performance of Ag/Al_(2)O_(3)catalysts(SA)was investigated for the selective catalytic reduction(SCR)of NO using C_...The effect of the modification of an alumina support with chloride on the structure and the catalytic performance of Ag/Al_(2)O_(3)catalysts(SA)was investigated for the selective catalytic reduction(SCR)of NO using C_(3)H_(6)or H_(2)/C_(3)H_(6)as reductants.The Ag/Al_(2)O_(3)catalyst and Cl^(–)-modified Ag/Al_(2)O_(3)catalysts(SA-Cl)were prepared by a conventional impregnation method and characterized by X-ray diffraction,Brunauer-Emmett-Teller isotherm analysis,electron probe microanalysis,transmission electron microscopy,UV-Vis diffuse reflectance spectroscopy,X-ray photoelectron spectroscopy,and hydrogen temperature-programmed reduction.The catalytic activities in the C3H6-SCR and H_(2)/C3H6-SCR reactions were evaluated,and the reaction mechanism was studied using in situ diffuse reflectance infrared Fourier transform spectroscopy and synchrotron vacuum ultraviolet photoionization mass spectroscopy(SVUV-PIMS).We found that Cl^(-)modification of the alumina-supported Ag/Al_(2)O_(3)catalysts facilitated the formation of oxidized silver species(Ag_(n)^(ᵟ+))that catalyze the moderate-temperature oxidation of hydrocarbons into partial oxidation products(mainly acetate species)capable of participating in the SCR reaction.The low-temperature promoting effect of H_(2)on the C3H6-SCR("hydrogen effect")was found to originate from the enhanced decomposition of strongly adsorbed nitrates on the catalyst surface and the conversion of these adsorbed species to–NCO and–CN species.This"H_(2)effect"occurs in the presence of Ag_(n)^(ᵟ+)species rather than the metallic Ag^(0)species.A gaseous intermediate,acrylonitrile(CH_(2)CHCN),was also identified in the H_(2)/C3H6-SCR reaction using SVUV-PIMS.These findings provide novel insights in the structure-activity relationship and reaction mechanisms of the SA-catalyzed HC-SCR reaction of NO.展开更多
Contactless acoustic manipulation of micro/nanoscale particles has attracted considerable attention owing to its near independence of the physical and chemical properties of the targets,making it universally applicabl...Contactless acoustic manipulation of micro/nanoscale particles has attracted considerable attention owing to its near independence of the physical and chemical properties of the targets,making it universally applicable to almost all biological systems.Thin-film bulk acoustic wave(BAW)resonators operating at gigahertz(GHz)frequencies have been demonstrated to generate localized high-speed microvortices through acoustic streaming effects.Benefitting from the strong drag forces of the high-speed vortices,BAW-enabled GHz acoustic streaming tweezers(AST)have been applied to the trapping and enrichment of particles ranging in size from micrometers to less than 100 nm.However,the behavior of particles in such 3D microvortex systems is still largely unknown.In this work,the particle behavior(trapping,enrichment,and separation)in GHz AST is studied by theoretical analyses,3D simulations,and microparticle tracking experiments.It is found that the particle motion in the vortices is determined mainly by the balance between the acoustic streaming drag force and the acoustic radiation force.This work can provide basic design principles for AST-based lab-on-a-chip systems for a variety of applications.展开更多
This paper addresses a critical challenge in the design of MEMS actuators:the rejection of out-of-plane motion,specifically along the Z-axis,which can severely impact the precision and performance of these micro-actua...This paper addresses a critical challenge in the design of MEMS actuators:the rejection of out-of-plane motion,specifically along the Z-axis,which can severely impact the precision and performance of these micro-actuation systems.In many MEMS applications,unwanted out-of-plane displacement can lead to reduced accuracy in tasks such as optical steering,micro-manipulation,and scanning applications.In response to these limitations,this paper proposes a novel design technique that effectively rejects Z-axis motion by transforming the motion of the micro stage along the Z-axis into equivalent displacements between pairs of points on cantilevers.These point pairs are founded exhibiting variable common-mode and differential-mode motion characteristics,depending on whether the stage is undergoing in-plane(X/Y)or out-of-plane(Z)displacements.By connecting these point pairs with rods,differential motion between the points in the pairs is suppressed,reducing unwanted out-of-plane motion significantly.We provide a detailed analysis of this design methodology and present a practical application in the form of an electromagnetic large displacement MEMS actuator.This actuator undergoes a complete design-simulationmanufacturing-testing cycle,where the effectiveness of the Z-axis motion rejection structure is systematically evaluated,and compared against traditional designs.Experimental results reveal a significant improvement in performance,with static and dynamic travel ranges reaching±60μm and±400μm,respectively.Moreover,the Z-axis stiffness was enhanced by 68.5%,which is more than five times the improvement observed in the X/Y axes’stiffness.These results highlight the potential of the proposed method to provide a robust solution for out-of-plane motion suppression in MEMS actuators,offering improved performance without compromising other critical parameters such as displacement and actuation speed.展开更多
Light detection and ranging(LiDAR)is widely used for active three-dimensional(3D)perception.Beam scanning LiDAR provides high accuracy and long detection range with limited detection efficiency,while flash LiDAR can a...Light detection and ranging(LiDAR)is widely used for active three-dimensional(3D)perception.Beam scanning LiDAR provides high accuracy and long detection range with limited detection efficiency,while flash LiDAR can achieve high-efficiency detection through the snapshot approach at the expense of reduced accuracy and range.With the synergy of these distinct detection approaches,we develop a miniaturized dual-mode,reconfigurable beam forming device by cascading Pancharatnam-Berry phase and propagation phase metasurfaces,integrated with a microactuator.By modulating incident light polarization,we can switch the output beam of the device between the beam array scanning mode and flash illuminating mode.In the scanning mode,the device demonstrates a continuously tunable angular resolution and a±35°field of view(FoV)through driving the micro-actuator to achieve the lateral translation of±100μm.In the flash mode,uniform illumination across the entire FoV is achieved.As a proof of concept,we propose an adaptive 3D reconstruction scheme that leverages the device’s capability to switch operation modes and adjust detection resolution.Together,the proposed device and the detection scheme constitute a dualmode LiDAR system,demonstrating high adaptability to diverse environments and catalyze the applications of more efficient and compact 3D detection systems.展开更多
Point-cloud-projection-based stereo vision technology is widely applied in 3D reconstruction, robotic vision, and virtual reality. A metasurface, known for its exceptional light-field manipulation capabilities and com...Point-cloud-projection-based stereo vision technology is widely applied in 3D reconstruction, robotic vision, and virtual reality. A metasurface, known for its exceptional light-field manipulation capabilities and compact integration, offers a promising approach to reducing system size while enhancing functionality. In this work, we propose and implement a short-wave infrared 3D structured light detection system based on a metasurface supporting a bound state in the continuum(BIC). The designed BIC metasurface exhibits wavelength selectivity, generating a point cloud projection array exclusively under 1350 nm laser illumination, effectively minimizing interference from environmental light and enabling penetration through certain packaging materials opaque to visible light. Using this system, we successfully demonstrate 3D detection and reconstruction of concealed objects, such as lenses and workpieces, within opaque packaging. Our design provides a non-contact,penetrating 3D reconstruction approach for industrial inspection, offering potential applications in nondestructive quality control.展开更多
Flexible electromagnetic metamaterials are a potential candidate for the ideal material for electromagnetic control due to their unique physical properties and structure.Flexible electromagnetic metamaterials can be d...Flexible electromagnetic metamaterials are a potential candidate for the ideal material for electromagnetic control due to their unique physical properties and structure.Flexible electromagnetic metamaterials can be designed to exhibit specific responses to electromagnetic waves within a particular frequency range.Research shows that flexible electromagnetic metamaterials exhibit significant electromagnetic control characteristics in microwave,terahertz,infrared and other frequency bands.It has a wide range of applications in the fields of electromagnetic wave absorption and stealth,antennas and microwave devices,communication information and other fields.In this review,the currently popular fabrication methods of flexible electromagnetic metamaterials are first summarized,highlighting the electromagnetic modulation capability in different frequency bands.Then,the applications of flexible electromagnetic metamaterials in four aspects,namely electromagnetic stealth,temperature modulation,electromagnetic shielding,and wearable sensors,are elaborated and summarized in detail.In addition,this review also discusses the shortcomings and limitations of flexible electromagnetic metamaterials for electromagnetic control.Finally,the conclusion and perspective of the electromagnetic properties of flexible electromagnetic metamaterials are presented.展开更多
Selective hydrogenation is an important industrial catalytic process in chemical upgrading, where Pd-based catalysts are widely used because of their high hydrogenation activities. However, poor selectivity and short ...Selective hydrogenation is an important industrial catalytic process in chemical upgrading, where Pd-based catalysts are widely used because of their high hydrogenation activities. However, poor selectivity and short catalyst lifetime because of heavy coke formation have been major concerns. In this work, atomically dispersed Pd atoms were successfully synthesized on graphitic carbon nitride （g-C3N4） using atomic layer deposition. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy （HAADF-STEM） confirmed the dominant presence of isolated Pd atoms without Pd nanoparticle （NP） formation. During selective hydrogenation of acetylene in excess ethylene, the g-C3N4-supported Pd NP catalysts had strikingly higher ethylene selectivities than the conventional Pd/Al2O3 and Pd/SiO2 catalysts. In-situ X-ray photoemission spectroscopy revealed that the considerable charge transfer from the Pd NPs to g-C3N4 likely plays an important role in the catalytic performance enhancement. More impressively, the single-atom Pd1/C3N4 catalyst exhibited both higher ethylene selectivity and higher coking resistance. Our work demonstrates that the single-atom Pd catalyst is a promising candidate for improving both selectivity and coking-resistance in hydrogenation reactions.展开更多
Background:The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy(IMRT)as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma(NPC),but the radiation-rel...Background:The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy(IMRT)as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma(NPC),but the radiation-related complications and relatively high medical costs remain a consequential burden for the patients.Endoscopic nasopharyngectomy(ENPG)was successfully applied in recurrent NPC with radiation free and relatively low medical costs.In this study,we examined whether ENPG could be an effective treatment for localized stage I NPC.Methods:Ten newly diagnosed localized stage I NPC patients voluntarily received ENPG alone from June 2007 to September 2017 in Sun Yat-sen University Cancer Center.Simultaneously,the data of 329 stage I NPC patients treated with IMRT were collected and used as a reference cohort.The survival outcomes,quality of life(QOL),and medical costs between two groups were compared.Results:After a median follow-up of 59.0 months(95%CI 53.4-64.6),no death,locoregional recurrence,or distant metastasis was observed in the 10 patients treated with ENPG.The 5-year overall survival,local relapse-free survival,regional relapse-free survival,and distant metastasis-free survival among the ENPG-treated patients was similar to that among the IMRT-treated patients(100%vs.99.1%,100%vs.97.7%,100%vs.99.0%,100%vs.97.4%,respectively,P>0.05).In addition,compared with IMRT,ENPG was associated with decreased total medical costs($4090.42±1502.65 vs.$12620.88±4242.65,P<0.001)and improved QOL scores including dry mouth(3.3±10.5 vs.34.4±25.8,P<0.001)and sticky saliva(3.3±10.5 vs.32.6±23.3,P<0.001).Conclusions:ENPG alone was associated with promising long-term survival outcomes,low medical costs,and satisfactory QOL and might therefore be an alternative strategy for treating newly diagnosed localized stage I NPC patients who refused radiotherapy.However,the application of ENPG should be prudent,and prospective clinical tri-als were needed to further verify the results.展开更多
Background:Postradiation nasopharyngeal necrosis(PRNN)is a severe complication after radiotherapy in patients with nasopharyngeal carcinoma(NPC),which can severely affect the quality of life and threaten the patient’...Background:Postradiation nasopharyngeal necrosis(PRNN)is a severe complication after radiotherapy in patients with nasopharyngeal carcinoma(NPC),which can severely affect the quality of life and threaten the patient’s life.Only 13.4%-28.6%of patients can be cured by traditional repeated endoscopic debridement.Here,we introduced an innovative curative-intent endoscopic surgery for PRNN patients and evaluated its clinical efficacy.Methods:Clinical data of 72 PRNN patients who underwent radical endoscopic necrectomy,followed by reconstruc-tion using a posterior pedicle nasal septum and floor mucoperiosteum flap were analyzed to determine the efficacy of this surgery.The endpoints were complete re-epithelialization of the nasopharyngeal defect,relief of headache,and overall survival(OS).Results:All surgeries were successfully performed without any severe postoperative complications or death.The median value of numeric rating scales of pain decreased from 8 before surgery to 0 after surgery(P<0.001).Fifty-one patients(70.8%)achieved complete re-epithelialization of the nasopharyngeal defect.The number of cycles of radiotherapy(odds ratio[OR],7.254;95%confidence interval[CI]1.035-50.821;P=0.046),postoperative pathological result(OR,34.087;95%CI 3.168-366.746;P=0.004),and survival status of flap(OR,261.179;95%CI 17.176-3971.599;P<0.001)were independent risk factors of re-epithelialization of the nasopharyngeal defects.Postoperative patho-logical result(hazard ratio[HR],5.018;95%CI 1.970-12.782;P=0.001)was an independent prognostic factor for OS.The 2-year OS rate of the entire cohort was 77.9%.Conclusion:Curative-intent endoscopic necrectomy followed by construction using the posterior pedicle nasal septum and floor mucoperiosteum flap is a novel,safe,and effective treatment of PRNN in patients with NPC.展开更多
Soft open points(SOPs)are power electronic devices that may replace conventional normally-open points in distribution networks.They can be used for active power flow control,reactive power compensation,fault isolation...Soft open points(SOPs)are power electronic devices that may replace conventional normally-open points in distribution networks.They can be used for active power flow control,reactive power compensation,fault isolation,and service restoration through network reconfiguration with enhanced operation flexibility and grid resiliency.Due to unbalanced loading conditions,the voltage unbalance issue,as a common problem in distribution networks,has negative impacts on distribution network operation.In this paper,a control strategy of voltage unbalance compensation for feeders using SOPs is proposed.With the power flow control,three-phase current is regulated simultaneously to mitigate the unbalanced voltage between neighboring feeders where SOPs are installed.Feeder voltage unbalance and current unbalance among three phases are compensated with the injection of negative-sequence and zero-sequence current from SOPs.Especially in response to power outages,three-phase voltage of isolated loads is regulated to be balanced by the control of SOPs connected to the feeders under faults,even if the loads are unbalanced.A MATLAB/Simulink model of the IEEE 13-bus test feeder with an SOP across feeder ends is implemented,and experimental tests on a hardware-in-the-loop platform are implemented to validate the effectiveness of the proposed control strategy.展开更多
Model catalysts approach is widely adopted in fundamental studies of complex heterogeneous cataly-sis.Traditional model catalysts are single crystal-based model catalysts,whose results,however,some-times suffer from t...Model catalysts approach is widely adopted in fundamental studies of complex heterogeneous cataly-sis.Traditional model catalysts are single crystal-based model catalysts,whose results,however,some-times suffer from the"material gap"and"pressure gap"when applied to working catalysts.Recently,uniform catalytic nanocrystals with well-defined structures have emerged,and we have put forward a concept of nanocrystal-based model catalysts for fundamental studies of complex heterogeneous ca-talysis under conditions approaching working catalysts as closely as possible.In this perspective,we summarize our research progresses on Cu_(2)O-based nanocrystal model catalysts.Following a brief in-troduction,we summarize controlled synthesis of uniform Cu_(2)O nanocrystals with various morpholo-gies,morphology-dependent surface compositions and structures and surface chemistry of uniform Cu_(2)O nanocrystals,and heterogeneous catalysis of Cu_(2)O-based nanocrystals.Finally,we conclude the concept of nanocrystal-based model catalysts and outlook that uniform nanocrystals can act not only as model catalysts but also as efficient catalysts.展开更多
Exhaled breath analysis has attracted considerable attention as a noninvasive and portable health diagnosis method due to numerous advantages,such as convenience,safety,simplicity,and avoidance of discomfort.Based on ...Exhaled breath analysis has attracted considerable attention as a noninvasive and portable health diagnosis method due to numerous advantages,such as convenience,safety,simplicity,and avoidance of discomfort.Based on many studies,exhaled breath analysis is a promising medical detection technology capable of diagnosing different diseases by analyzing the concentration,type and other characteristics of specific gases.In the existing gas analysis technology,the electronic nose(eNose)analysis method has great advantages of high sensitivity,rapid response,real-time monitoring,ease of use and portability.Herein,this review is intended to provide an overview of the application of human exhaled breath components in disease diagnosis,existing breath testing technologies and the development and research status of electronic nose technology.In the electronic nose technology section,the three aspects of sensors,algorithms and existing systems are summarized in detail.Moreover,the related challenges and limitations involved in the abovementioned technologies are also discussed.Finally,the conclusion and perspective of eNose technology are presented.展开更多
Supramolecules are considered as promising materials for volatile organic compounds(VOCs)sensing applications.The proper understanding of the sorption process taking place in host-vip interactions is critical in imp...Supramolecules are considered as promising materials for volatile organic compounds(VOCs)sensing applications.The proper understanding of the sorption process taking place in host-vip interactions is critical in improving the pattern recognition of supramolecules-based sensing arrays.Here,we report a novel approach to investigate the dynamic host-vip recognition process by employing a bulk acoustic wave(BAW)resonator capable of producing multiple oscillation amplitudes and simultaneously recording multiple responses to VOCs.Self-assembled monolayers(SAMs)ofβ-cyclodextrin(β-CD)were modified on four BAW sensors to demonstrate the gas-surface interactions regarding oscillation amplitude and SAM length.Based on the method,a virtual sensor array(VSA)type electronic nose(e-nose)can be realized by pattern recognition of multiple responses at different oscillation amplitudes of a single sensor.VOCs analysis was realized respectively by using principal component analysis(PCA)for individual VOC identification and linear discriminant analysis(LDA)for VOCs mixtures classification.展开更多
Terahertz (THz) wave manipulation, especially the beam deflection, plays an essential role in various applications, such as next-generation communication, space exploration, and high-resolution imaging. Current THz op...Terahertz (THz) wave manipulation, especially the beam deflection, plays an essential role in various applications, such as next-generation communication, space exploration, and high-resolution imaging. Current THz optical components and devices are hampered by their large bulk sizes and passive responses, limiting the development of high-performance, miniaturized THz microsystems. Tunable metasurfaces offer a powerful dynamic optical platform for controlling the propagation of electromagnetic waves. In this article, we presented a mechanically tunable metasurface (MTM), which can achieve terahertz beam deflection and vary the intensity of the anomalous reflected terahertz wave by changing the air gap between the metallic resonator (MR) array with phase discontinuities and Au ground plane. The absence of lossy spacer materials substantially enhances deflection efficiency. The device was fabricated by a combination of the surface and bulk-micromachining processes. The THz beam steering capability was characterized using terahertz time domain spectroscopy. When the air gap is 50 μm, the maximum deflection coefficient reaches 0.60 at 0.61 THz with a deflection angle of ~44.5°, consistent with theoretical predictions. We further established an electrically tunable miniaturized THz device for dynamic beam steering by introducing a micro voice coil motor to control the air gap continuously. It is shown that our designed MTM demonstrates a high modulation depth of deflection coefficient (~ 62.5%) in the target steered angle at the operating frequency. Our results showcase the potential of the proposed MTM as a platform for high-efficiency THz beam manipulation.展开更多
Miniaturization of health care,biomedical,and chemical systems is highly desirable for developing pointof-care testing(POCT)technologies.In system miniaturization,micropumps represent one of the major bottlenecks due ...Miniaturization of health care,biomedical,and chemical systems is highly desirable for developing pointof-care testing(POCT)technologies.In system miniaturization,micropumps represent one of the major bottlenecks due to their undesirable pumping performance at such small sizes.Here,we developed a microelectromechanical system fabricated acoustic micropump based on an ultrahigh-frequency bulk acoustic wave resonator.The concept of an inner-boundary-confined acoustic jet was introduced to facilitate unidirectional flow.Benefitting from the high resonant frequency and confined acoustic streaming,the micropump reaches 32.620 kPa/cm^(3)(pressure/size)and 11.800 ml/min∙cm^(3)(flow rate/size),showing a 2-order-of-magnitude improvement in the energy transduction efficiency compared with the existing acoustic micropumps.As a proof of concept,the micropump was constructed as a wearable and wirelessly powered integrated drug delivery system with a size of only 9×9×9 mm^(3)and a weight of 1.16 g.It was demonstrated for ocular disease treatment through animal experimentation and a human pilot test.With superior pumping performance,miniaturized pump size,ultralow power consumption,and complementary metal–oxide–semiconductor compatibility,we expect it to be readily applied to various POCT applications including clinical diagnosis,prognosis,and drug delivery systems.展开更多
基金the financial support received from the National Natural Science Foundation of China(Grant No.62174119)the 111 Project (Grant No.B07014)the Foundation for Talent Scientists of Nanchang Institute for Microtechnology of Tianjin University
文摘No-wash bioassays based on nanoparticles are used widely in biochemical procedures because of their responsive sensing and no need forwashing processes.Essential for no-wash biosensing are the interactions between nanoparticles and biomolecules,but it is challenging toachieve controlled bioconjugation of molecules on nanomaterials.Reported here is a way to actively improve nanoparticle-based no-washbioassays by enhancing the binding between biomolecules and gold nanoparticles via acoustic streaming generated by a gigahertz piezoelectricnanoelectromechanical resonator.Tunable micro-vortices are generated at the device-liquid interface,thereby accelerating the internalcirculating flow of the solution,bypassing the diffusion limitation,and thus improving the binding between the biomolecules and goldnanoparticles.Combined with fluorescence quenching,an enhanced and ultrafast no-wash biosensing assay is realized for specific proteins.The sensing method presented here is a versatile tool for different types of biomolecule detection with high efficiency and simplicity.
基金supported by the State Key Laboratory of Pathogens and Biosecurity(Grant No.SKLPBS2240).
文摘Accurate detection of dimethyl methylphosphonate(DMMP),a simulant for chemical warfare agents,is vital for both public safety and military defense.However,conventional detection methods suffer from low selectivity,owing to interference from structurally similar compounds.In this study,we present a highly sensitive and selective gas sensor utilizing a solid-mounted film bulk acoustic resonator based on carbon nanotubes functionalized with hexafluoroisopropanol(HFiP)to enhance DMMP detection.This approach leverages the strong hydrogen bonding between HFiP and DMMP molecules to significantly improve the sensor’s adsorption capacity and selectivity.To further refine selectivity and at the same time solve the cross-sensitivity problem of sensitive membranes,we introduce a virtual sensor array design,generated by modulating the input power to the resonator,which enables the sensor to operate in multiple response modes across varying vibrational amplitudes.These multimodal responses are subjected to linear discriminant analysis,allowing precise differentiation of DMMP from other volatile organic compounds such as tributyl phosphate and dimethyl phthalate.Our results demonstrate superior performance in terms of both sensitivity and selectivity,offering a robust solution for detecting low-concentration DMMP in complex environments.
基金financial supports from the National Key R&D Program of China (2021YFA1401200)Beijing Outstanding Young Scientist Program (BJJWZYJH01201910007022)+1 种基金National Natural Science Foundation of China (No. U21A20140, No. 92050117, No. 62105024) programBeijing Natural Science Foundation (JQ24028)
文摘Optical three-dimensional(3D)measurement is a critical tool in micro-nano manufacturing,the automotive industry,and medical technology due to its nondestructive nature,high precision,and sensitivity.However,passive light field system still requires a refractive primary lens to collect light of the scene,and structured light can not work well with the highly refractive object.Meta-optics,known for being lightweight,compact,and easily integrable,has enabled advancements in passive metalens-array light fields and active structured light techniques.Here,we propose and experimentally validate a novel 3D measurement metasystem.It features a transmitting metasurface generating chromatic line focuses as depth markers and a symmetrically arranged receiving metasurface collecting depth-dependent spectral responses.A lightweight,physically interpretable algorithm processes these data to yield high-precision depth information efficiently.Experiments on metallic and wafer materials demonstrate a depth accuracy of±20μm and lateral accuracy of±10μm.This single-layer optical metasystem,characterized by simplicity,micro-level accuracy,easy installation and scalability,shows potential for diverse applications,including process control,surface morphology analysis,and production measurement.
文摘The effect of the modification of an alumina support with chloride on the structure and the catalytic performance of Ag/Al_(2)O_(3)catalysts(SA)was investigated for the selective catalytic reduction(SCR)of NO using C_(3)H_(6)or H_(2)/C_(3)H_(6)as reductants.The Ag/Al_(2)O_(3)catalyst and Cl^(–)-modified Ag/Al_(2)O_(3)catalysts(SA-Cl)were prepared by a conventional impregnation method and characterized by X-ray diffraction,Brunauer-Emmett-Teller isotherm analysis,electron probe microanalysis,transmission electron microscopy,UV-Vis diffuse reflectance spectroscopy,X-ray photoelectron spectroscopy,and hydrogen temperature-programmed reduction.The catalytic activities in the C3H6-SCR and H_(2)/C3H6-SCR reactions were evaluated,and the reaction mechanism was studied using in situ diffuse reflectance infrared Fourier transform spectroscopy and synchrotron vacuum ultraviolet photoionization mass spectroscopy(SVUV-PIMS).We found that Cl^(-)modification of the alumina-supported Ag/Al_(2)O_(3)catalysts facilitated the formation of oxidized silver species(Ag_(n)^(ᵟ+))that catalyze the moderate-temperature oxidation of hydrocarbons into partial oxidation products(mainly acetate species)capable of participating in the SCR reaction.The low-temperature promoting effect of H_(2)on the C3H6-SCR("hydrogen effect")was found to originate from the enhanced decomposition of strongly adsorbed nitrates on the catalyst surface and the conversion of these adsorbed species to–NCO and–CN species.This"H_(2)effect"occurs in the presence of Ag_(n)^(ᵟ+)species rather than the metallic Ag^(0)species.A gaseous intermediate,acrylonitrile(CH_(2)CHCN),was also identified in the H_(2)/C3H6-SCR reaction using SVUV-PIMS.These findings provide novel insights in the structure-activity relationship and reaction mechanisms of the SA-catalyzed HC-SCR reaction of NO.
基金The authors gratefully acknowledge financial support from the National Key R&D Program of China(2018YFE0118700)the Natural Science Foundation of China(NSFC No.62174119)+1 种基金Tianjin Applied Basic Research and Advanced Technology(17JCJQJC43600)the 111 Project(B07014).
文摘Contactless acoustic manipulation of micro/nanoscale particles has attracted considerable attention owing to its near independence of the physical and chemical properties of the targets,making it universally applicable to almost all biological systems.Thin-film bulk acoustic wave(BAW)resonators operating at gigahertz(GHz)frequencies have been demonstrated to generate localized high-speed microvortices through acoustic streaming effects.Benefitting from the strong drag forces of the high-speed vortices,BAW-enabled GHz acoustic streaming tweezers(AST)have been applied to the trapping and enrichment of particles ranging in size from micrometers to less than 100 nm.However,the behavior of particles in such 3D microvortex systems is still largely unknown.In this work,the particle behavior(trapping,enrichment,and separation)in GHz AST is studied by theoretical analyses,3D simulations,and microparticle tracking experiments.It is found that the particle motion in the vortices is determined mainly by the balance between the acoustic streaming drag force and the acoustic radiation force.This work can provide basic design principles for AST-based lab-on-a-chip systems for a variety of applications.
基金the National Natural Science Foundation of China(Grant No.U21A6003&Grant No.U24A6006).
文摘This paper addresses a critical challenge in the design of MEMS actuators:the rejection of out-of-plane motion,specifically along the Z-axis,which can severely impact the precision and performance of these micro-actuation systems.In many MEMS applications,unwanted out-of-plane displacement can lead to reduced accuracy in tasks such as optical steering,micro-manipulation,and scanning applications.In response to these limitations,this paper proposes a novel design technique that effectively rejects Z-axis motion by transforming the motion of the micro stage along the Z-axis into equivalent displacements between pairs of points on cantilevers.These point pairs are founded exhibiting variable common-mode and differential-mode motion characteristics,depending on whether the stage is undergoing in-plane(X/Y)or out-of-plane(Z)displacements.By connecting these point pairs with rods,differential motion between the points in the pairs is suppressed,reducing unwanted out-of-plane motion significantly.We provide a detailed analysis of this design methodology and present a practical application in the form of an electromagnetic large displacement MEMS actuator.This actuator undergoes a complete design-simulationmanufacturing-testing cycle,where the effectiveness of the Z-axis motion rejection structure is systematically evaluated,and compared against traditional designs.Experimental results reveal a significant improvement in performance,with static and dynamic travel ranges reaching±60μm and±400μm,respectively.Moreover,the Z-axis stiffness was enhanced by 68.5%,which is more than five times the improvement observed in the X/Y axes’stiffness.These results highlight the potential of the proposed method to provide a robust solution for out-of-plane motion suppression in MEMS actuators,offering improved performance without compromising other critical parameters such as displacement and actuation speed.
基金supported by National Natural Science Foundation of China(Grant No.U21A6003)National Key Research and Development Program of China(Grant No.2023YFB3906300)+1 种基金support from the Beijing Outstanding Young Scientist Program(Grant No.JWZQ20240101028)support from National Natural Science Foundation of China(Grant No.62475018).
文摘Light detection and ranging(LiDAR)is widely used for active three-dimensional(3D)perception.Beam scanning LiDAR provides high accuracy and long detection range with limited detection efficiency,while flash LiDAR can achieve high-efficiency detection through the snapshot approach at the expense of reduced accuracy and range.With the synergy of these distinct detection approaches,we develop a miniaturized dual-mode,reconfigurable beam forming device by cascading Pancharatnam-Berry phase and propagation phase metasurfaces,integrated with a microactuator.By modulating incident light polarization,we can switch the output beam of the device between the beam array scanning mode and flash illuminating mode.In the scanning mode,the device demonstrates a continuously tunable angular resolution and a±35°field of view(FoV)through driving the micro-actuator to achieve the lateral translation of±100μm.In the flash mode,uniform illumination across the entire FoV is achieved.As a proof of concept,we propose an adaptive 3D reconstruction scheme that leverages the device’s capability to switch operation modes and adjust detection resolution.Together,the proposed device and the detection scheme constitute a dualmode LiDAR system,demonstrating high adaptability to diverse environments and catalyze the applications of more efficient and compact 3D detection systems.
基金National Key Researchand Development Program of China(2022YFB4600204)Beijing Outstanding Young Scientist Program(BJJWZYJH01201910007022)+1 种基金National Natural Science Foundation of China(12104046,62105024,61775019,62475018,U21A20140)Natural Science Foundation of Beijing Municipality(JQ24028).
文摘Point-cloud-projection-based stereo vision technology is widely applied in 3D reconstruction, robotic vision, and virtual reality. A metasurface, known for its exceptional light-field manipulation capabilities and compact integration, offers a promising approach to reducing system size while enhancing functionality. In this work, we propose and implement a short-wave infrared 3D structured light detection system based on a metasurface supporting a bound state in the continuum(BIC). The designed BIC metasurface exhibits wavelength selectivity, generating a point cloud projection array exclusively under 1350 nm laser illumination, effectively minimizing interference from environmental light and enabling penetration through certain packaging materials opaque to visible light. Using this system, we successfully demonstrate 3D detection and reconstruction of concealed objects, such as lenses and workpieces, within opaque packaging. Our design provides a non-contact,penetrating 3D reconstruction approach for industrial inspection, offering potential applications in nondestructive quality control.
基金funded by the National Natural Science Foundation of China(No.62204020)the Beijing Municipal Education Commission Scientific Research Project(No.KM202211232016)+1 种基金the Beijing Outstanding Young Scientist Program(No.JWZQ20240101028)the China Association for Science and Technology Young Outstanding Scientists Funding Program(No.YESS20210023)。
文摘Flexible electromagnetic metamaterials are a potential candidate for the ideal material for electromagnetic control due to their unique physical properties and structure.Flexible electromagnetic metamaterials can be designed to exhibit specific responses to electromagnetic waves within a particular frequency range.Research shows that flexible electromagnetic metamaterials exhibit significant electromagnetic control characteristics in microwave,terahertz,infrared and other frequency bands.It has a wide range of applications in the fields of electromagnetic wave absorption and stealth,antennas and microwave devices,communication information and other fields.In this review,the currently popular fabrication methods of flexible electromagnetic metamaterials are first summarized,highlighting the electromagnetic modulation capability in different frequency bands.Then,the applications of flexible electromagnetic metamaterials in four aspects,namely electromagnetic stealth,temperature modulation,electromagnetic shielding,and wearable sensors,are elaborated and summarized in detail.In addition,this review also discusses the shortcomings and limitations of flexible electromagnetic metamaterials for electromagnetic control.Finally,the conclusion and perspective of the electromagnetic properties of flexible electromagnetic metamaterials are presented.
基金Acknowledgements This work was supported by the Thousand Talents Plan, the National Natural Science Foundation of China （Nos. 21473169, 21673215, and 51402283）, the Fundamental Research Funds for the Central Universities （Nos. WK2060030017 and WK2060190026）, and the startup funds from the University of Science and Technology of China. This work was also supported by Hefei Science Center （No. 2015HSC-UP010）.
文摘Selective hydrogenation is an important industrial catalytic process in chemical upgrading, where Pd-based catalysts are widely used because of their high hydrogenation activities. However, poor selectivity and short catalyst lifetime because of heavy coke formation have been major concerns. In this work, atomically dispersed Pd atoms were successfully synthesized on graphitic carbon nitride （g-C3N4） using atomic layer deposition. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy （HAADF-STEM） confirmed the dominant presence of isolated Pd atoms without Pd nanoparticle （NP） formation. During selective hydrogenation of acetylene in excess ethylene, the g-C3N4-supported Pd NP catalysts had strikingly higher ethylene selectivities than the conventional Pd/Al2O3 and Pd/SiO2 catalysts. In-situ X-ray photoemission spectroscopy revealed that the considerable charge transfer from the Pd NPs to g-C3N4 likely plays an important role in the catalytic performance enhancement. More impressively, the single-atom Pd1/C3N4 catalyst exhibited both higher ethylene selectivity and higher coking resistance. Our work demonstrates that the single-atom Pd catalyst is a promising candidate for improving both selectivity and coking-resistance in hydrogenation reactions.
基金Funding was provided by the National Natural Science Foundation of China(Nos.81572912,81772895)Guangdong Public Welfare Research and Capacity Building Projects(2014B020212005)+1 种基金the Program of Sun Yat-Sen University for Clinical Research 5010 Program(No.201310)the Major Project of Sun Yat-Sen University for the New Cross Subject,the Special Support Program for High-level Talents in Sun Yat-Sen University Cancer Center(to M.Y.Chen),Guangdong Province Science and Technology Development Special Funds(Frontier and Key Technology Innovation Direction-Major Science and Technology Project),Guangzhou Science and Technology Planning Project-Production and Research Collaborative Innovation Major Project
文摘Background:The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy(IMRT)as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma(NPC),but the radiation-related complications and relatively high medical costs remain a consequential burden for the patients.Endoscopic nasopharyngectomy(ENPG)was successfully applied in recurrent NPC with radiation free and relatively low medical costs.In this study,we examined whether ENPG could be an effective treatment for localized stage I NPC.Methods:Ten newly diagnosed localized stage I NPC patients voluntarily received ENPG alone from June 2007 to September 2017 in Sun Yat-sen University Cancer Center.Simultaneously,the data of 329 stage I NPC patients treated with IMRT were collected and used as a reference cohort.The survival outcomes,quality of life(QOL),and medical costs between two groups were compared.Results:After a median follow-up of 59.0 months(95%CI 53.4-64.6),no death,locoregional recurrence,or distant metastasis was observed in the 10 patients treated with ENPG.The 5-year overall survival,local relapse-free survival,regional relapse-free survival,and distant metastasis-free survival among the ENPG-treated patients was similar to that among the IMRT-treated patients(100%vs.99.1%,100%vs.97.7%,100%vs.99.0%,100%vs.97.4%,respectively,P>0.05).In addition,compared with IMRT,ENPG was associated with decreased total medical costs($4090.42±1502.65 vs.$12620.88±4242.65,P<0.001)and improved QOL scores including dry mouth(3.3±10.5 vs.34.4±25.8,P<0.001)and sticky saliva(3.3±10.5 vs.32.6±23.3,P<0.001).Conclusions:ENPG alone was associated with promising long-term survival outcomes,low medical costs,and satisfactory QOL and might therefore be an alternative strategy for treating newly diagnosed localized stage I NPC patients who refused radiotherapy.However,the application of ENPG should be prudent,and prospective clinical tri-als were needed to further verify the results.
基金supported by the National Natural Science Foundation of China(Nos.81572912,81772895,and 81572848)Guangdong Public Welfare Research and Capacity Building Projects(2014B020212005)+5 种基金the Program of Sun Yat-Sen University for Clinical Research 5010 Program(No.201310 and No.2015011)the Major Project of Sun Yat-Sen University for the New Cross Subjectthe Special Support Program for High-level Talents in Sun Yat-Sen University Cancer Center(2015076316)the National Key Research and Development Program of China(2016YFC0905000)Guangdong Province Science and Technology Development Special Funds(Frontier and Key Technology Innovation Direction-Major Science and Technology Project,703040078088)Guangzhou Science and Technology Planning Project-Production and Research Collaborative Innovation Major Project(201604020182).
文摘Background:Postradiation nasopharyngeal necrosis(PRNN)is a severe complication after radiotherapy in patients with nasopharyngeal carcinoma(NPC),which can severely affect the quality of life and threaten the patient’s life.Only 13.4%-28.6%of patients can be cured by traditional repeated endoscopic debridement.Here,we introduced an innovative curative-intent endoscopic surgery for PRNN patients and evaluated its clinical efficacy.Methods:Clinical data of 72 PRNN patients who underwent radical endoscopic necrectomy,followed by reconstruc-tion using a posterior pedicle nasal septum and floor mucoperiosteum flap were analyzed to determine the efficacy of this surgery.The endpoints were complete re-epithelialization of the nasopharyngeal defect,relief of headache,and overall survival(OS).Results:All surgeries were successfully performed without any severe postoperative complications or death.The median value of numeric rating scales of pain decreased from 8 before surgery to 0 after surgery(P<0.001).Fifty-one patients(70.8%)achieved complete re-epithelialization of the nasopharyngeal defect.The number of cycles of radiotherapy(odds ratio[OR],7.254;95%confidence interval[CI]1.035-50.821;P=0.046),postoperative pathological result(OR,34.087;95%CI 3.168-366.746;P=0.004),and survival status of flap(OR,261.179;95%CI 17.176-3971.599;P<0.001)were independent risk factors of re-epithelialization of the nasopharyngeal defects.Postoperative patho-logical result(hazard ratio[HR],5.018;95%CI 1.970-12.782;P=0.001)was an independent prognostic factor for OS.The 2-year OS rate of the entire cohort was 77.9%.Conclusion:Curative-intent endoscopic necrectomy followed by construction using the posterior pedicle nasal septum and floor mucoperiosteum flap is a novel,safe,and effective treatment of PRNN in patients with NPC.
基金The work of R.You was supported by Shandong Provincial Key Research and Development Program(No.2019JZZY010902)Shandong Provincial Natural Science Foundation(No.ZR2020ME197).
文摘Soft open points(SOPs)are power electronic devices that may replace conventional normally-open points in distribution networks.They can be used for active power flow control,reactive power compensation,fault isolation,and service restoration through network reconfiguration with enhanced operation flexibility and grid resiliency.Due to unbalanced loading conditions,the voltage unbalance issue,as a common problem in distribution networks,has negative impacts on distribution network operation.In this paper,a control strategy of voltage unbalance compensation for feeders using SOPs is proposed.With the power flow control,three-phase current is regulated simultaneously to mitigate the unbalanced voltage between neighboring feeders where SOPs are installed.Feeder voltage unbalance and current unbalance among three phases are compensated with the injection of negative-sequence and zero-sequence current from SOPs.Especially in response to power outages,three-phase voltage of isolated loads is regulated to be balanced by the control of SOPs connected to the feeders under faults,even if the loads are unbalanced.A MATLAB/Simulink model of the IEEE 13-bus test feeder with an SOP across feeder ends is implemented,and experimental tests on a hardware-in-the-loop platform are implemented to validate the effectiveness of the proposed control strategy.
基金supported by the National Natural Science Foundation of China(Nos.21525313,U1930203,and 22102146)the Chinese Academy of Sciences,and the Changjiang Scholars Program of the Chinese Ministry of Education.
文摘Model catalysts approach is widely adopted in fundamental studies of complex heterogeneous cataly-sis.Traditional model catalysts are single crystal-based model catalysts,whose results,however,some-times suffer from the"material gap"and"pressure gap"when applied to working catalysts.Recently,uniform catalytic nanocrystals with well-defined structures have emerged,and we have put forward a concept of nanocrystal-based model catalysts for fundamental studies of complex heterogeneous ca-talysis under conditions approaching working catalysts as closely as possible.In this perspective,we summarize our research progresses on Cu_(2)O-based nanocrystal model catalysts.Following a brief in-troduction,we summarize controlled synthesis of uniform Cu_(2)O nanocrystals with various morpholo-gies,morphology-dependent surface compositions and structures and surface chemistry of uniform Cu_(2)O nanocrystals,and heterogeneous catalysis of Cu_(2)O-based nanocrystals.Finally,we conclude the concept of nanocrystal-based model catalysts and outlook that uniform nanocrystals can act not only as model catalysts but also as efficient catalysts.
基金financially supported by the National Natural Science Foundation of China(NSFC)(No.U21A6003)Beijing Nova Program(No.Z211100002121075)+1 种基金Key R&D Program of Shandong Province,China(2022CXPT045)Qin Xin Talents Cultivation Program of Beijing Information Science&Technology University(No.QXTCP A202101).
文摘Exhaled breath analysis has attracted considerable attention as a noninvasive and portable health diagnosis method due to numerous advantages,such as convenience,safety,simplicity,and avoidance of discomfort.Based on many studies,exhaled breath analysis is a promising medical detection technology capable of diagnosing different diseases by analyzing the concentration,type and other characteristics of specific gases.In the existing gas analysis technology,the electronic nose(eNose)analysis method has great advantages of high sensitivity,rapid response,real-time monitoring,ease of use and portability.Herein,this review is intended to provide an overview of the application of human exhaled breath components in disease diagnosis,existing breath testing technologies and the development and research status of electronic nose technology.In the electronic nose technology section,the three aspects of sensors,algorithms and existing systems are summarized in detail.Moreover,the related challenges and limitations involved in the abovementioned technologies are also discussed.Finally,the conclusion and perspective of eNose technology are presented.
文摘Supramolecules are considered as promising materials for volatile organic compounds(VOCs)sensing applications.The proper understanding of the sorption process taking place in host-vip interactions is critical in improving the pattern recognition of supramolecules-based sensing arrays.Here,we report a novel approach to investigate the dynamic host-vip recognition process by employing a bulk acoustic wave(BAW)resonator capable of producing multiple oscillation amplitudes and simultaneously recording multiple responses to VOCs.Self-assembled monolayers(SAMs)ofβ-cyclodextrin(β-CD)were modified on four BAW sensors to demonstrate the gas-surface interactions regarding oscillation amplitude and SAM length.Based on the method,a virtual sensor array(VSA)type electronic nose(e-nose)can be realized by pattern recognition of multiple responses at different oscillation amplitudes of a single sensor.VOCs analysis was realized respectively by using principal component analysis(PCA)for individual VOC identification and linear discriminant analysis(LDA)for VOCs mixtures classification.
基金the National Key R&D Program of China(Grant No.2021YFB2011800)the National Nature Science Foundation of China(Grant No.U21A6003)+1 种基金the United Science Foundation of Ministry of Education of China(Grant No.8091B032115)the Beijing Natural Science Foundation(Grant No.422068).X.Z.acknowledges the startup funding from Tsinghua University.
文摘Terahertz (THz) wave manipulation, especially the beam deflection, plays an essential role in various applications, such as next-generation communication, space exploration, and high-resolution imaging. Current THz optical components and devices are hampered by their large bulk sizes and passive responses, limiting the development of high-performance, miniaturized THz microsystems. Tunable metasurfaces offer a powerful dynamic optical platform for controlling the propagation of electromagnetic waves. In this article, we presented a mechanically tunable metasurface (MTM), which can achieve terahertz beam deflection and vary the intensity of the anomalous reflected terahertz wave by changing the air gap between the metallic resonator (MR) array with phase discontinuities and Au ground plane. The absence of lossy spacer materials substantially enhances deflection efficiency. The device was fabricated by a combination of the surface and bulk-micromachining processes. The THz beam steering capability was characterized using terahertz time domain spectroscopy. When the air gap is 50 μm, the maximum deflection coefficient reaches 0.60 at 0.61 THz with a deflection angle of ~44.5°, consistent with theoretical predictions. We further established an electrically tunable miniaturized THz device for dynamic beam steering by introducing a micro voice coil motor to control the air gap continuously. It is shown that our designed MTM demonstrates a high modulation depth of deflection coefficient (~ 62.5%) in the target steered angle at the operating frequency. Our results showcase the potential of the proposed MTM as a platform for high-efficiency THz beam manipulation.
基金the National Natural Science Foundation of China(NSFC No.62174119)the National Key R&D Program of China(2018YFE0118700)+6 种基金the 111 Project(B07014)the Foundation for Talent Scientists of Nanchang Institute for Micro-technology of Tianjin University,the Tianjin Key Medical Discipline(Specialty)Construction Project(TJYXZDXK-016A)the National Program on Key Research Project of China(2022YFC2404502)the National Natural Science Foundation of China(82271118)the Tianjin Science and Technology Project(21JCZDJC01190)the Tianjin Health Research Project(TJWJ2022XK036)the Key Project of Tianjin Eye Hospital(QF:YKYB2007).
文摘Miniaturization of health care,biomedical,and chemical systems is highly desirable for developing pointof-care testing(POCT)technologies.In system miniaturization,micropumps represent one of the major bottlenecks due to their undesirable pumping performance at such small sizes.Here,we developed a microelectromechanical system fabricated acoustic micropump based on an ultrahigh-frequency bulk acoustic wave resonator.The concept of an inner-boundary-confined acoustic jet was introduced to facilitate unidirectional flow.Benefitting from the high resonant frequency and confined acoustic streaming,the micropump reaches 32.620 kPa/cm^(3)(pressure/size)and 11.800 ml/min∙cm^(3)(flow rate/size),showing a 2-order-of-magnitude improvement in the energy transduction efficiency compared with the existing acoustic micropumps.As a proof of concept,the micropump was constructed as a wearable and wirelessly powered integrated drug delivery system with a size of only 9×9×9 mm^(3)and a weight of 1.16 g.It was demonstrated for ocular disease treatment through animal experimentation and a human pilot test.With superior pumping performance,miniaturized pump size,ultralow power consumption,and complementary metal–oxide–semiconductor compatibility,we expect it to be readily applied to various POCT applications including clinical diagnosis,prognosis,and drug delivery systems.
