Flexible,compact,lightweight and sustainable power sources are indispensable for modern wearable and personal electronics and small-unmanned aerial vehicles(UAVs).Hierarchical honeycomb has the unique merits of compac...Flexible,compact,lightweight and sustainable power sources are indispensable for modern wearable and personal electronics and small-unmanned aerial vehicles(UAVs).Hierarchical honeycomb has the unique merits of compact mesostructures,excellent energy absorption properties and considerable weight to strength ratios.Herein,a honeycomb-inspired triboelectric nanogenerator(h-TENG)is proposed for biomechanical and UAV morphing wing energy harvesting based on contact triboelectrification wavy surface of cellular honeycomb structure.The wavy surface comprises a multilayered thin film structure(combining polyethylene terephthalate,silver nanowires and fluorinated ethylene propylene)fabricated through high-temperature thermoplastic molding and wafer-level bonding process.With superior synchronization of large amounts of energy generation units with honeycomb cells,the manufactured h-TENG prototype produces the maximum instantaneous open-circuit voltage,short-circuit current and output power of 1207 V,68.5μA and 12.4 mW,respectively,corresponding to a remarkable peak power density of 0.275 mW cm^(−3)(or 2.48 mW g^(−1))under hand pressing excitations.Attributed to the excellent elastic property of self-rebounding honeycomb structure,the flexible and transparent h-TENG can be easily pressed,bent and integrated into shoes for real-time insole plantar pressure mapping.The lightweight and compact h-TENG is further installed into a morphing wing of small UAVs for efficiently converting the flapping energy of ailerons into electricity for the first time.This research demonstrates this new conceptualizing single h-TENG device’s versatility and viability for broad-range real-world application scenarios.展开更多
The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 3...The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.展开更多
One of the critical issues for electret/triboelectric devices is the poor charge viability and stability in humid environments.Herein,we propose a new origami-inspired“W-tube”-shaped triboelectric nanogenerator(W-TE...One of the critical issues for electret/triboelectric devices is the poor charge viability and stability in humid environments.Herein,we propose a new origami-inspired“W-tube”-shaped triboelectric nanogenerator(W-TENG)with two thin-film electrets folded based on Miura-origami.The Miura-origami fold is capable of transforming flat materials with large surface areas into reduced and compressed complex 3D structures with parallelogram tessellations.The triboelectric power generation components can thus be hermetically sealed inside the“W-tube”to avoid contact with the external humid environment.Furthermore,the elastic nature of the Miura-origami fold endows the proposed W-TENG device with excellent deformability,flexibility,and stretchability.Therefore,it is capable of harvesting kinetic energy from various directions and forms of movement,including horizontal pressing,vertical tapping,and lateral bending.The compact,light weight,and self-rebounding properties of the origami structure also make it convenient for integration into wearable devices.Various parameters of the W-TENG are intensively investigated,including the number of power generation units,original height of the device,acceleration magnitude,excitation direction,and water-proof capability.Triggered by hand tapping impulse excitation in the horizontal and vertical directions,the instantaneous open-circuit voltages can reach 791 V and 116 V with remarkable optimum powers of 691μW at 50MΩand 220μW at 35 MΩ,respectively.The outcomes of this work demonstrate the fusion of the ancient art of origami,material science,and energy conversion techniques to realize flexible,multifunctional,and water-proof TENG devices.展开更多
Li_(2)O-Al_(2)O_(3)-SiO_(2)(LAS)glass-ceramics were prepared by a melting method.Effects of different Al_(2)O_(3)content on the structure,crystallization,transmittance and fracture toughness of LAS glassceramics were ...Li_(2)O-Al_(2)O_(3)-SiO_(2)(LAS)glass-ceramics were prepared by a melting method.Effects of different Al_(2)O_(3)content on the structure,crystallization,transmittance and fracture toughness of LAS glassceramics were investigated by means of XRD,FESEM and other methods as well.The results showed that the glass transition temperature and crystallization temperature of samples increased as the content of Al_(2)O_(3)increased from 4.1 wt%to 13.1 wt%,which restrained the precipitation of lithium disilicate crystals.The main crystalline phase of glass-ceramics transformed from lithium disilicate and petalite to silicon dioxide,which reduced the fracture toughness of glass-ceramics.When the Al_(2)O_(3)content was 7.1 wt%,the specimen had outstanding transmittance and fracture toughness.The transmittance was 90.32%.The fracture toughness was 1.13 MPa•m^(1/2).Compared with high-alumina glass,the fracture toughness of the glass-ceramic was greatly improved,and it could be used as a new type of protective material for mobile devices.展开更多
The imaging capability of conventional lenses is mainly limited by the diffraction of light,and the so-called superlens has been developed allowing the recovery of evanescent waves in the focal plane.However,the remar...The imaging capability of conventional lenses is mainly limited by the diffraction of light,and the so-called superlens has been developed allowing the recovery of evanescent waves in the focal plane.However,the remarkable focusing behavi-or of the superlens is greatly confined in the near-field regime due to the exponential decay of evanescent waves.To tackle this issue,we design a waveguide metasurface-based superlens with an extraordinary quasi-far-field focusing capability beyond the diffraction limit in the present work.Specifically,we analyze the underlying physical mechanism and provide experimental verification of the proposed superlens.The metasurface superlens is formed by an array of gradient nanoslits perforated in a gold slab,and supports transverse-electric(TE)waveguide modes under linearly polar-ized illumination along the long axis of the slits.Numerical results illustrate that exciting such TE waveguide modes can modulate not only optical phase but also evanescent waves.Consequently,some high-spatial-frequency waves can con-tribute to the focusing of the superlens,leading to the quasi-far-field super-resolution focusing of light.Under 405 nm illu-mination and oil immersion,the fabricated superlens shows a focus spot of 98 nm(i.e.λ/4.13)at a focal distance of 1.49μm(i.e.3.68λ)using an oil immersion objective,breaking the diffraction limit ofλ/2.38 in the quasi-far field regime.The developed metasurface optical superlens with such extraordinary capabilities promises exciting avenues to nanolitho-graphy and ultra-small optoelectronic devices.展开更多
The mode localization phenomenon of disordered weakly coupled resonators(WCRs)is being used as a novel transduction scheme to further enhance the sensitivity of micromechanical resonant sensors.In this paper,two novel...The mode localization phenomenon of disordered weakly coupled resonators(WCRs)is being used as a novel transduction scheme to further enhance the sensitivity of micromechanical resonant sensors.In this paper,two novel characteristics of mode localization are described.First,we found that the anti-resonance loci behave as a linear function of the stiffness perturbation.The antiresonance behavior can be regarded as a new manifestation of mode localization in the frequency domain,and mode localization occurs at a deeper level as the anti-resonance approaches closer to the resonance.The anti-resonance loci can be used to identify the symmetry of the WCRs and the locations of the perturbation.Second,by comparing the forced localization responses of the WCRs under both the single-resonator-driven(SRD)scheme and the double-resonator-driven(DRD)scheme,we demonstrated that the DRD scheme extends the linear measurement scale while sacrificing a certain amount of sensitivity.We also demonstrated experimentally that the amplitude ratio-based sensitivity under the DRD scheme is approximately an order of magnitude lower than that under the SRD scheme,that is,the amplitude ratio-based sensitivity is−70.44%(Nm^(−1))^(−1) under the DRD scheme,while it is−785.6%(Nm^(−)1)^(−1) under the SRD scheme.These characteristics of mode localization are valuable for the design and control of WCR-based sensors.展开更多
Based on the commercially available avalanche photodiodes, the basic needs of gated-mode operation for single photon are discussed. Gated-mode technique based on the experimental data for detection of single photon is...Based on the commercially available avalanche photodiodes, the basic needs of gated-mode operation for single photon are discussed. Gated-mode technique based on the experimental data for detection of single photon is analyzed at communication wavelengths so that the basic operation parameters can decide properly for efficient detection of single photon. The bias voltage has related to the punch-through voltage in combining the cooling technique with synchronization to decrease the dark counts.展开更多
This paper introduces the design and manu- facturing technology of aerospace microelectromechanical systems （MEMS） characterized by high performance, multi-variety, and small batch. Moreover, several kinds of specia...This paper introduces the design and manu- facturing technology of aerospace microelectromechanical systems （MEMS） characterized by high performance, multi-variety, and small batch. Moreover, several kinds of special MEMS devices with high precision, high reliability, and environmental adaptability, as well as their typical applications in the fields of aeronautics and aerospace, are presented.展开更多
基金This research is supported by the National Natural Science Foundation of China Grant(Nos.51705429&61801525)the Fundamental Research Funds for the Central Universities,Guangdong Natural Science Funds Grant(2018A030313400)+1 种基金Space Science and Technology Foundation,111 Project No.B13044UK Engineering and Physical Sciences Research Council(EPSRC)for support under grant EP/P018998/1,Newton Mobility Grant(IE161019)through Royal Society.
文摘Flexible,compact,lightweight and sustainable power sources are indispensable for modern wearable and personal electronics and small-unmanned aerial vehicles(UAVs).Hierarchical honeycomb has the unique merits of compact mesostructures,excellent energy absorption properties and considerable weight to strength ratios.Herein,a honeycomb-inspired triboelectric nanogenerator(h-TENG)is proposed for biomechanical and UAV morphing wing energy harvesting based on contact triboelectrification wavy surface of cellular honeycomb structure.The wavy surface comprises a multilayered thin film structure(combining polyethylene terephthalate,silver nanowires and fluorinated ethylene propylene)fabricated through high-temperature thermoplastic molding and wafer-level bonding process.With superior synchronization of large amounts of energy generation units with honeycomb cells,the manufactured h-TENG prototype produces the maximum instantaneous open-circuit voltage,short-circuit current and output power of 1207 V,68.5μA and 12.4 mW,respectively,corresponding to a remarkable peak power density of 0.275 mW cm^(−3)(or 2.48 mW g^(−1))under hand pressing excitations.Attributed to the excellent elastic property of self-rebounding honeycomb structure,the flexible and transparent h-TENG can be easily pressed,bent and integrated into shoes for real-time insole plantar pressure mapping.The lightweight and compact h-TENG is further installed into a morphing wing of small UAVs for efficiently converting the flapping energy of ailerons into electricity for the first time.This research demonstrates this new conceptualizing single h-TENG device’s versatility and viability for broad-range real-world application scenarios.
基金support from diverse funding sources,including the National Key Program for S&T Research and Development of the Ministry of Science and Technology(MOST),Yifang Wang's Science Studio of the Ten Thousand Talents Project,the CAS Key Foreign Cooperation Grant,the National Natural Science Foundation of China(NSFC)Beijing Municipal Science&Technology Commission,the CAS Focused Science Grant,the IHEP Innovation Grant,the CAS Lead Special Training Programthe CAS Center for Excellence in Particle Physics,the CAS International Partnership Program,and the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.
基金This research is supported by National Natural Science Foundation of China Grants(No.51705429&No.61801525)Science,Technology,and Innovation Commission of Shenzhen Municipality JCYJ20170815161054349+4 种基金Fundamental Research Funds for the Central Universities No.31020190503003National Natural Science Foundation of Shaanxi Province No.2018JQ5030Laboratory Fund of Science and Technology on Micro-system Laboratory No.614280401010417111 Project No.B13044a Guangdong Natural Science Funds Grant(2018A030313400).
文摘One of the critical issues for electret/triboelectric devices is the poor charge viability and stability in humid environments.Herein,we propose a new origami-inspired“W-tube”-shaped triboelectric nanogenerator(W-TENG)with two thin-film electrets folded based on Miura-origami.The Miura-origami fold is capable of transforming flat materials with large surface areas into reduced and compressed complex 3D structures with parallelogram tessellations.The triboelectric power generation components can thus be hermetically sealed inside the“W-tube”to avoid contact with the external humid environment.Furthermore,the elastic nature of the Miura-origami fold endows the proposed W-TENG device with excellent deformability,flexibility,and stretchability.Therefore,it is capable of harvesting kinetic energy from various directions and forms of movement,including horizontal pressing,vertical tapping,and lateral bending.The compact,light weight,and self-rebounding properties of the origami structure also make it convenient for integration into wearable devices.Various parameters of the W-TENG are intensively investigated,including the number of power generation units,original height of the device,acceleration magnitude,excitation direction,and water-proof capability.Triggered by hand tapping impulse excitation in the horizontal and vertical directions,the instantaneous open-circuit voltages can reach 791 V and 116 V with remarkable optimum powers of 691μW at 50MΩand 220μW at 35 MΩ,respectively.The outcomes of this work demonstrate the fusion of the ancient art of origami,material science,and energy conversion techniques to realize flexible,multifunctional,and water-proof TENG devices.
基金State Key Laboratory of Silicate Materials for Architectures(Wuhan University of Technology)(No.2011DA105356)。
文摘Li_(2)O-Al_(2)O_(3)-SiO_(2)(LAS)glass-ceramics were prepared by a melting method.Effects of different Al_(2)O_(3)content on the structure,crystallization,transmittance and fracture toughness of LAS glassceramics were investigated by means of XRD,FESEM and other methods as well.The results showed that the glass transition temperature and crystallization temperature of samples increased as the content of Al_(2)O_(3)increased from 4.1 wt%to 13.1 wt%,which restrained the precipitation of lithium disilicate crystals.The main crystalline phase of glass-ceramics transformed from lithium disilicate and petalite to silicon dioxide,which reduced the fracture toughness of glass-ceramics.When the Al_(2)O_(3)content was 7.1 wt%,the specimen had outstanding transmittance and fracture toughness.The transmittance was 90.32%.The fracture toughness was 1.13 MPa•m^(1/2).Compared with high-alumina glass,the fracture toughness of the glass-ceramic was greatly improved,and it could be used as a new type of protective material for mobile devices.
基金support by the National Natural Science Foundation of China(52075410,51975483,51622509)the Fundamental Research Funds for the Central Universities(31020190504001)+3 种基金the 111 Project(B13044),the Dean Fund(2019GDYJY05)the Collaborative Innov-ation Center Project of Shaanxi Provincial Department of Education(20JY031)the Natural Science Basic Research Plan in Shaanxi Province of China(2018JQ6012)the Hong Kong Polytechnic University through the“Life Science Research”project(1-ZVH9),and the City University of Hong Kong(9610456).
文摘The imaging capability of conventional lenses is mainly limited by the diffraction of light,and the so-called superlens has been developed allowing the recovery of evanescent waves in the focal plane.However,the remarkable focusing behavi-or of the superlens is greatly confined in the near-field regime due to the exponential decay of evanescent waves.To tackle this issue,we design a waveguide metasurface-based superlens with an extraordinary quasi-far-field focusing capability beyond the diffraction limit in the present work.Specifically,we analyze the underlying physical mechanism and provide experimental verification of the proposed superlens.The metasurface superlens is formed by an array of gradient nanoslits perforated in a gold slab,and supports transverse-electric(TE)waveguide modes under linearly polar-ized illumination along the long axis of the slits.Numerical results illustrate that exciting such TE waveguide modes can modulate not only optical phase but also evanescent waves.Consequently,some high-spatial-frequency waves can con-tribute to the focusing of the superlens,leading to the quasi-far-field super-resolution focusing of light.Under 405 nm illu-mination and oil immersion,the fabricated superlens shows a focus spot of 98 nm(i.e.λ/4.13)at a focal distance of 1.49μm(i.e.3.68λ)using an oil immersion objective,breaking the diffraction limit ofλ/2.38 in the quasi-far field regime.The developed metasurface optical superlens with such extraordinary capabilities promises exciting avenues to nanolitho-graphy and ultra-small optoelectronic devices.
基金This work was supported by the National Natural Science Foundation of China under Grant 51575454.
文摘The mode localization phenomenon of disordered weakly coupled resonators(WCRs)is being used as a novel transduction scheme to further enhance the sensitivity of micromechanical resonant sensors.In this paper,two novel characteristics of mode localization are described.First,we found that the anti-resonance loci behave as a linear function of the stiffness perturbation.The antiresonance behavior can be regarded as a new manifestation of mode localization in the frequency domain,and mode localization occurs at a deeper level as the anti-resonance approaches closer to the resonance.The anti-resonance loci can be used to identify the symmetry of the WCRs and the locations of the perturbation.Second,by comparing the forced localization responses of the WCRs under both the single-resonator-driven(SRD)scheme and the double-resonator-driven(DRD)scheme,we demonstrated that the DRD scheme extends the linear measurement scale while sacrificing a certain amount of sensitivity.We also demonstrated experimentally that the amplitude ratio-based sensitivity under the DRD scheme is approximately an order of magnitude lower than that under the SRD scheme,that is,the amplitude ratio-based sensitivity is−70.44%(Nm^(−1))^(−1) under the DRD scheme,while it is−785.6%(Nm^(−)1)^(−1) under the SRD scheme.These characteristics of mode localization are valuable for the design and control of WCR-based sensors.
基金National"973"Project(G2001039302) Key S & T Project of Guangdong Province(2003A103405) Key S&T Project of Guangzhou City(1992-2-035-01)
文摘Based on the commercially available avalanche photodiodes, the basic needs of gated-mode operation for single photon are discussed. Gated-mode technique based on the experimental data for detection of single photon is analyzed at communication wavelengths so that the basic operation parameters can decide properly for efficient detection of single photon. The bias voltage has related to the punch-through voltage in combining the cooling technique with synchronization to decrease the dark counts.
文摘This paper introduces the design and manu- facturing technology of aerospace microelectromechanical systems （MEMS） characterized by high performance, multi-variety, and small batch. Moreover, several kinds of special MEMS devices with high precision, high reliability, and environmental adaptability, as well as their typical applications in the fields of aeronautics and aerospace, are presented.
