Lateral optical forces induced by linearly polarized laser beams have been predicted to deflect dipolar particles with opposite chiralities toward opposite transversal directions.These“chirality-dependent”forces can...Lateral optical forces induced by linearly polarized laser beams have been predicted to deflect dipolar particles with opposite chiralities toward opposite transversal directions.These“chirality-dependent”forces can offer new possibilities for passive all-optical enantioselective sorting of chiral particles,which is essential to the nanoscience and drug industries.However,previous chiral sorting experiments focused on large particles with diameters in the geometrical-optics regime.Here,we demonstrate,for the first time,the robust sorting of Mie(size~wavelength)chiral particles with different handedness at an air–water interface using optical lateral forces induced by a single linearly polarized laser beam.The nontrivial physical interactions underlying these chirality-dependent forces distinctly differ from those predicted for dipolar or geometrical-optics particles.The lateral forces emerge from a complex interplay between the light polarization,lateral momentum enhancement,and out-of-plane light refraction at the particle-water interface.The sign of the lateral force could be reversed by changing the particle size,incident angle,and polarization of the obliquely incident light.展开更多
The power of controlling objects with mind has captivated a popular fascination to human beings.One possible path is to employ brain signal collecting technologies together with emerging programmable metasurfaces(PM),...The power of controlling objects with mind has captivated a popular fascination to human beings.One possible path is to employ brain signal collecting technologies together with emerging programmable metasurfaces(PM),whose functions or operating modes can be switched or customized via on-site programming or pre-defined software.Nevertheless,most of existing PMs are wire-connected to users,manually-controlled and not real-time.Here,we propose the concept of remotely mind-controlled metasurface(RMCM)via brainwaves.Rather than DC voltage from power supply or AC voltages from signal generators,the metasurface is controlled by brainwaves collected in real time and transmitted wirelessly from the user.As an example,we demonstrated a RMCM whose scattering pattern can be altered dynamically according to the user’s brain waves via Bluetooth.The attention intensity information is extracted as the control signal and a mapping between attention intensity and scattering pattern of the metasurface is established.With such a framework,we experimentally demonstrated and verified a prototype of such metasurface system which can be remotely controlled by the user to modify its scattering pattern.This work paves a new way to intelligent metasurfaces and may find applications in health monitoring,5G/6G communications,smart sensors,etc.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
Recent years have witnessed significant progress in quantum communication and quantum internet with the emerging quantum photonic chips,whose characteristics of scalability,stability,and low cost,flourish and open up ...Recent years have witnessed significant progress in quantum communication and quantum internet with the emerging quantum photonic chips,whose characteristics of scalability,stability,and low cost,flourish and open up new possibilities in miniaturized footprints.Here,we provide an overview of the advances in quantum photonic chips for quantum communication,beginning with a summary of the prevalent photonic integrated fabrication platforms and key components for integrated quantum communication systems.We then discuss a range of quantum communication applications,such as quantum key distribution and quantum teleportation.Finally,the review culminates with a perspective on challenges towards high-performance chip-based quantum communication,as well as a glimpse into future opportunities for integrated quantum networks.展开更多
On the Tibetan Plateau, the alpine meadow is the most widespread vegetation type. The alpine meadow has a low biological productivity and low vegetation coverage in the growing season. The daytime NEE between the atmo...On the Tibetan Plateau, the alpine meadow is the most widespread vegetation type. The alpine meadow has a low biological productivity and low vegetation coverage in the growing season. The daytime NEE between the atmosphere and the alpine meadow ecosystem was influenced by solar radiation. To analyze the characteristics of change in NEE and to calculate the parameters related to photosynthesis and respiration in different solar radiation environments, the NEE measurements were taken in Damxung from July to August in 2003, 2004, 2005 and 2006 using the eddy covariance technique. Solar radiation was grouped into three levels according to the net radiation, which was more than 155 W m-2 d-1 on clear days, 144±5 W m-2 d-1 on partly cloudy days and less than 134 W m-2 d-1 on cloudy days. The diurnal relationships between NEE and PAR varied with differences in solar radiation, which was a rectangular hyperbola form on clear days, two different concave curves on partly cloudy days and an irregular triangle form on cloudy days. The mean CO2 absorption rate showed a decreasing trend with increasing solar radiation. The daytime absorption maximum occurred around 10：00 on clear days with an average of slightly less –0.2 mg m-2 d-1, around 11：00 on partly cloudy days with an average of about –0.2 mg m-2 d-1, and around 12：00 on cloudy days with an average of about –0.25 mg m-2 d-1. As solar radiation increased, the Amax and the Q10 decreased. However, the R10 increased and the maximum of the α occurred on partly cloudy days. The optimum net solar radiation was about 134–155 W m-2 d-1, which induced a PAR of about 1800-2000 μmol m-2 s-1 and soil temperature at a depth of 5 cm of about 14℃. Therefore, on the Tibetan Plateau, the alpine meadow ecosystem will have a higher carbon absorption potential while solar radiation decreases in the future.展开更多
Objects with different shapes,materials and temperatures can emit distinct polarizations and spectral information in mid-infrared band,which provides a unique signature in the transparent window for object identificat...Objects with different shapes,materials and temperatures can emit distinct polarizations and spectral information in mid-infrared band,which provides a unique signature in the transparent window for object identification.However,the crosstalk among various polarization and wavelength channels prevents from accurate mid-infrared detections at high signal-to-noise ratio.Here,we report full-polarization metasurfaces to break the inherent eigen-polarization constraint over the wavelengths in mid-infrared.This recipe enables to select arbitrary orthogonal polarization basis at individual wavelength independently,therefore alleviating the crosstalk and efficiency degradation.A six-channel all-silicon metasurface is specifically presented to project focused mid-infrared light to distinct positions at three wavelengths,each with a pair of arbitrarily chosen orthogonal polarizations.An isolation ratio of 117 between neighboring polarization channels is experimentally recorded,exhibiting detection sensitivity one order of magnitude higher than existing infrared detectors.Remarkably,the high aspect ratio~30 of our meta-structures manufactured by deep silicon etching technology at temperature−150℃ guarantees the large and precise phase dispersion control over a broadband from 3 to 4.5μm.We believe our results would benefit the noise-immune mid-infrared detections in remote sensing and space-to-ground communications.展开更多
Design of multiple-feed lens antennas requires multivariate and multi-objective optimization processes,which can be accelerated by PSO algorithms.However,the PSO algorithm often fails to achieve optimal results with l...Design of multiple-feed lens antennas requires multivariate and multi-objective optimization processes,which can be accelerated by PSO algorithms.However,the PSO algorithm often fails to achieve optimal results with limited computation resources since spaces of candidate solutions are quite large for lens antenna designs.This paper presents a design paradigm for multiple-feed lens antennas based on a physics-assisted particle swarm optimization(PA-PSO)algorithm,which guides the swarm of particles based on laws of physics.As a proof of concept,a design of compact metalens antenna is proposed,which measures unprecedented performances,such as a field of view at±55°,a 21.7 dBi gain with a flatness within 4 dB,a 3-dB bandwidth>12°,and a compact design with a f-number of 0.2.The proposed PA-PSO algorithm reaches the optimal results 6 times faster than the ordinary PSO algorithm,which endows promising applications in the multivariate and multi-objective optimization processes,including but not limited to metalens antenna designs.展开更多
China is experiencing accelerated urbanisation,with a large number of people moving from rural to urban areas[1].It has resulted in large losses in the net primary production(NPP),biodiversity and carbon stocks and an...China is experiencing accelerated urbanisation,with a large number of people moving from rural to urban areas[1].It has resulted in large losses in the net primary production(NPP),biodiversity and carbon stocks and an increase in environmental pollution and CO_(2)emissions[2–4].In 2015,196 countries signed the Paris Agreement and committed to setting long-term goals to jointly manage climate change and reduce their individual emissions,aiming to control the increase in global average temperature from the pre-industrial level to below 2℃and to curtail the temperature rise within 1.5℃till the end of the 21st century[5].China is bolstering its efforts to achieve the climate change mitigation goals and has announced a plan for achieving carbon neutrality by 2060[6].The carbon neutrality goal poses a challenge to the current policies promoting rapid urbanisation across China.展开更多
Dear Editor,Tribe Andropogoneae within the family Poaceae encompasses92 genera and 1200 species of substantial agronomic and ecological importance,as represented by maize(Zea mays),sorghum(Sorghum bicolor),sugarcane(S...Dear Editor,Tribe Andropogoneae within the family Poaceae encompasses92 genera and 1200 species of substantial agronomic and ecological importance,as represented by maize(Zea mays),sorghum(Sorghum bicolor),sugarcane(Saccharum officinarum),Miscanthus,and many other crops(Welker et al.,2020).展开更多
Exceptional point (EP) is a special degeneracy of non-Hermitian systems. One-dimensional transmission systems operating at EPs are widely studied and applied to chiral conversion and sensing. Lately, two-dimensional s...Exceptional point (EP) is a special degeneracy of non-Hermitian systems. One-dimensional transmission systems operating at EPs are widely studied and applied to chiral conversion and sensing. Lately, two-dimensional systems at EPs have been exploited for their exotic scattering features, yet so far been limited to only the non-visible waveband. Here, we report a universal paradigm for achieving a high-efficiency EP in the visible by leveraging interlayer loss to accurately control the interplay between the lossy structure and scattering lightwaves. A bilayer framework is demonstrated to reflect back the incident light from the left side ( | r_(−1) | >0.999) and absorb the incident light from the right side ( | r_(+1) | < 10^(–4)). As a proof of concept, a bilayer metasurface is demonstrated to reflect and absorb the incident light with experimental efficiencies of 88% and 85%, respectively, at 532 nm. Our results open the way for a new class of nanoscale devices and power up new opportunities for EP physics.展开更多
Infectious diseases severely threaten public health and global biosafety.In addition to transmission through the air,pathogenic microorganisms have also been detected in environmental liquid samples,such as sewage wat...Infectious diseases severely threaten public health and global biosafety.In addition to transmission through the air,pathogenic microorganisms have also been detected in environmental liquid samples,such as sewage water.Conventional biochemical detection methodologies are time-consuming and cost-ineffective,and their detection limits hinder early diagnosis.In the present study,ultrafine plasmonic fiber probes with a diameter of 125μm are fabricated for clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)-12a-mediated sensing of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Single-stranded DNA exposed on the fiber surface is trans-cleaved by the Cas12a enzyme to release gold nanoparticles that are immobilized onto the fiber surface,causing a sharp reduction in the surface plasmon resonance(SPR)wavelength.The proposed fiber probe is virus-specific with the limit of detection of~2,300 copies/ml,and genomic copy numbers can be reflected as shifts in wavelengths.A total of 21 sewage water samples have been examined,and the data obtained are consistent with those of quantitative polymerase chain reaction(qPCR).In addition,the Omicron variant and its mutation sites have been fast detected using S gene-specific Cas12a.This study provides an accurate and convenient approach for the real-time surveillance of microbial contamination in sewage water.展开更多
The subject of“atmospheric radiation”includes not only fundamental theories on atmospheric gaseous absorption and the scattering and radiative transfer of particles(molecules,cloud,and aerosols),but also their appli...The subject of“atmospheric radiation”includes not only fundamental theories on atmospheric gaseous absorption and the scattering and radiative transfer of particles(molecules,cloud,and aerosols),but also their applications in weather,climate,and atmospheric remote sensing,and is an essential part of the atmospheric sciences.This review includes two parts(Part I and PartⅡ);following the first part on gaseous absorption and particle scattering,this part(PartⅡ)reports the progress that has been made in radiative transfer theories,models,and their common applications,focusing particularly on the contributions from Chinese researchers.The recent achievements on radiative transfer models and methods developed for weather and climate studies and for atmospheric remote sensing are firstly reviewed.Then,the associated applications,such as surface radiation estimation,satellite remote sensing algorithms,radiative parameterization for climate models,and radiative-forcing related climate change studies are summarized,which further reveals the importance of radiative transfer theories and models.展开更多
We demonstrate a smart sensor for label-free multicomponent chemical analysis using a single label-free ring resonator to acquire the entire resonant spectrum of the mixture and a neural network model to predict the c...We demonstrate a smart sensor for label-free multicomponent chemical analysis using a single label-free ring resonator to acquire the entire resonant spectrum of the mixture and a neural network model to predict the composition for multicomponent analysis. The smart sensor shows a high prediction accuracy with a low rootmean-squared error ranging only from 0.13 to 2.28 mg/m L. The predicted concentrations of each component in the testing dataset almost all fall within the 95% prediction bands. With its simple label-free detection strategy and high accuracy, the smart sensor promises great potential for multicomponent analysis applications in many fields.展开更多
Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free ...Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free and bound forms were identified by liquid chromatography electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS)in both positive and negative modes.Further investigation of chemical constituents in the EtOAc extract led to the isolation of eleven individual compounds,and their chemical structures were identified as(−)-epicatechin(1),(−)-loliolide(2),(−)-syringaresinol-4-O-β-D-glucopyranoside(3),alloside of benzyl alcohol(4),3-[(6-O-hexopyranosylhexopyranosyl)oxy]-2-(palmitoyloxy)propyl(9Z,12Z,15Z)-9,12,15-octadecatrienoate(5),apocynoside I(6),quercetin-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucopyranoside(8),[1-acetyloxy-3-[3,4,5-trihydroxy-6-[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxymethyl]oxan-2-yl]oxypropan-2-yl]hexadecanoate(9),1-stearoyl-2-palmitoyl-sn-glycerol(10),and 3-hexene-l-O-β-D-glucoside(11)using a series of spectroscopic methods.Compounds 2–5 and 9–11 were isolated for the first time from A.venetum,while antioxidant experiments showed that compounds 1,7,and 8 displayed strong DPPH and ABTS+radical scavenging activities.This study represents the first investigation of bound phenolic compounds with potential health benefits in the residue of A.venetum tea.展开更多
基金the financial support from the Ministry of Education,Singapore(Project No.R-263-000-D11-114)from the National Research Foundation,Prime Minister’s Office,Singapore under its Competitive Research Program(CRP award NRFCRP15-2015-03 and NRFCRP15-2015-04)+4 种基金the Singapore National Research Foundation under the Competitive Research Program(NRF-CRP13-2014-01)the Incentive for Research&Innovation Scheme(1102-IRIS-05-04)administered by PUBthe Fundamental Research Funds for the Central Universities(DUT19RC(3)046)supported by the Spanish Ministerio de Economia y Competitividad(MICINN)and European Regional Development Fund(ERDF)Project FIS2015-69295-C3-3-Pthe Basque Dep.de Educacion Project PI-2016-1-0041.
文摘Lateral optical forces induced by linearly polarized laser beams have been predicted to deflect dipolar particles with opposite chiralities toward opposite transversal directions.These“chirality-dependent”forces can offer new possibilities for passive all-optical enantioselective sorting of chiral particles,which is essential to the nanoscience and drug industries.However,previous chiral sorting experiments focused on large particles with diameters in the geometrical-optics regime.Here,we demonstrate,for the first time,the robust sorting of Mie(size~wavelength)chiral particles with different handedness at an air–water interface using optical lateral forces induced by a single linearly polarized laser beam.The nontrivial physical interactions underlying these chirality-dependent forces distinctly differ from those predicted for dipolar or geometrical-optics particles.The lateral forces emerge from a complex interplay between the light polarization,lateral momentum enhancement,and out-of-plane light refraction at the particle-water interface.The sign of the lateral force could be reversed by changing the particle size,incident angle,and polarization of the obliquely incident light.
基金National Natural Science Foundation of China under Grant Nos.61971435,62101588,62101589National Key Research and Development Program of China(Grant No.:SQ2017YFA0700201)+1 种基金C.-W.Q.is supported by a grant(R-261-518-004-720|A-0005947-16-00)from Advanced Research and Technology Innovation Centre(ARTIC)in National University of Singapore.
文摘The power of controlling objects with mind has captivated a popular fascination to human beings.One possible path is to employ brain signal collecting technologies together with emerging programmable metasurfaces(PM),whose functions or operating modes can be switched or customized via on-site programming or pre-defined software.Nevertheless,most of existing PMs are wire-connected to users,manually-controlled and not real-time.Here,we propose the concept of remotely mind-controlled metasurface(RMCM)via brainwaves.Rather than DC voltage from power supply or AC voltages from signal generators,the metasurface is controlled by brainwaves collected in real time and transmitted wirelessly from the user.As an example,we demonstrated a RMCM whose scattering pattern can be altered dynamically according to the user’s brain waves via Bluetooth.The attention intensity information is extracted as the control signal and a mapping between attention intensity and scattering pattern of the metasurface is established.With such a framework,we experimentally demonstrated and verified a prototype of such metasurface system which can be remotely controlled by the user to modify its scattering pattern.This work paves a new way to intelligent metasurfaces and may find applications in health monitoring,5G/6G communications,smart sensors,etc.
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 work was supported by the Singapore Ministry of Education(MOE)Tier 3 grant(MOE2017-T3-1-001),NRF grant(MOH-000926),A*STAR research grant(SERC-A18A5b0056)PUB Singapore's National Water Agency grant(PUB-1804-0082).
文摘Recent years have witnessed significant progress in quantum communication and quantum internet with the emerging quantum photonic chips,whose characteristics of scalability,stability,and low cost,flourish and open up new possibilities in miniaturized footprints.Here,we provide an overview of the advances in quantum photonic chips for quantum communication,beginning with a summary of the prevalent photonic integrated fabrication platforms and key components for integrated quantum communication systems.We then discuss a range of quantum communication applications,such as quantum key distribution and quantum teleportation.Finally,the review culminates with a perspective on challenges towards high-performance chip-based quantum communication,as well as a glimpse into future opportunities for integrated quantum networks.
基金The Major Basic Research Development Program of China, No.2010CB833501 No.2010CB951704+1 种基金Knowledge Innovation Program of Chinese Academy of Sciences, No.KSCXZ-YW-N-44Knowledge Inno-vation Program of IGSNRR, CAS, No.Y0V00230ZZ
文摘On the Tibetan Plateau, the alpine meadow is the most widespread vegetation type. The alpine meadow has a low biological productivity and low vegetation coverage in the growing season. The daytime NEE between the atmosphere and the alpine meadow ecosystem was influenced by solar radiation. To analyze the characteristics of change in NEE and to calculate the parameters related to photosynthesis and respiration in different solar radiation environments, the NEE measurements were taken in Damxung from July to August in 2003, 2004, 2005 and 2006 using the eddy covariance technique. Solar radiation was grouped into three levels according to the net radiation, which was more than 155 W m-2 d-1 on clear days, 144±5 W m-2 d-1 on partly cloudy days and less than 134 W m-2 d-1 on cloudy days. The diurnal relationships between NEE and PAR varied with differences in solar radiation, which was a rectangular hyperbola form on clear days, two different concave curves on partly cloudy days and an irregular triangle form on cloudy days. The mean CO2 absorption rate showed a decreasing trend with increasing solar radiation. The daytime absorption maximum occurred around 10：00 on clear days with an average of slightly less –0.2 mg m-2 d-1, around 11：00 on partly cloudy days with an average of about –0.2 mg m-2 d-1, and around 12：00 on cloudy days with an average of about –0.25 mg m-2 d-1. As solar radiation increased, the Amax and the Q10 decreased. However, the R10 increased and the maximum of the α occurred on partly cloudy days. The optimum net solar radiation was about 134–155 W m-2 d-1, which induced a PAR of about 1800-2000 μmol m-2 s-1 and soil temperature at a depth of 5 cm of about 14℃. Therefore, on the Tibetan Plateau, the alpine meadow ecosystem will have a higher carbon absorption potential while solar radiation decreases in the future.
基金supported by National Key Research and Development Program of China(2018YFA0306200,2017YFA0700200,2017YFA0700202)National Natural Science Foundation of China(62204249,62222514,61731010,61875218,61991440,and 91850208)+9 种基金Youth Innovation Promotion Association of Chinese Academy of Sciences(Y2021070)Strategic Priority Research Program of Chinese Academy of Sciences(XDB43010200)Shanghai Rising-Star Program(20QA1410400)Shanghai Science and Technology Committee(23ZR1482000,20JC1416000,and 22JC1402900)Natural Science Foundation of Zhejiang Province(LR22F050004)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)Shanghai Human Resources and Social Security Bureau(2022670)China Postdoctoral Science Foundation(2022TQ0353 and 2022M713261)partially carried out at the Center for Micro and Nanoscale Research and Fabrication in University of Science and Technology of Chinathe support by AME Individual Research Grant(IRG)funded by A*STAR,Singapore(Grant No.A2083c0060).
文摘Objects with different shapes,materials and temperatures can emit distinct polarizations and spectral information in mid-infrared band,which provides a unique signature in the transparent window for object identification.However,the crosstalk among various polarization and wavelength channels prevents from accurate mid-infrared detections at high signal-to-noise ratio.Here,we report full-polarization metasurfaces to break the inherent eigen-polarization constraint over the wavelengths in mid-infrared.This recipe enables to select arbitrary orthogonal polarization basis at individual wavelength independently,therefore alleviating the crosstalk and efficiency degradation.A six-channel all-silicon metasurface is specifically presented to project focused mid-infrared light to distinct positions at three wavelengths,each with a pair of arbitrarily chosen orthogonal polarizations.An isolation ratio of 117 between neighboring polarization channels is experimentally recorded,exhibiting detection sensitivity one order of magnitude higher than existing infrared detectors.Remarkably,the high aspect ratio~30 of our meta-structures manufactured by deep silicon etching technology at temperature−150℃ guarantees the large and precise phase dispersion control over a broadband from 3 to 4.5μm.We believe our results would benefit the noise-immune mid-infrared detections in remote sensing and space-to-ground communications.
基金supported by the National Natural Science Foundation of China(61975026,62375232,6237523262205246 and 61875030)Creative Research Groups of the National Natural Science Foundation of Sichuan Province(2023NSFSC1973)+1 种基金the Shanghai Pilot Program for Basic Research,the National Key Research and Development Program of China(No.2023YFF0613600)Science and Technology Commission of Shanghai Municipality(No.22ZR1432400).
文摘Design of multiple-feed lens antennas requires multivariate and multi-objective optimization processes,which can be accelerated by PSO algorithms.However,the PSO algorithm often fails to achieve optimal results with limited computation resources since spaces of candidate solutions are quite large for lens antenna designs.This paper presents a design paradigm for multiple-feed lens antennas based on a physics-assisted particle swarm optimization(PA-PSO)algorithm,which guides the swarm of particles based on laws of physics.As a proof of concept,a design of compact metalens antenna is proposed,which measures unprecedented performances,such as a field of view at±55°,a 21.7 dBi gain with a flatness within 4 dB,a 3-dB bandwidth>12°,and a compact design with a f-number of 0.2.The proposed PA-PSO algorithm reaches the optimal results 6 times faster than the ordinary PSO algorithm,which endows promising applications in the multivariate and multi-objective optimization processes,including but not limited to metalens antenna designs.
基金supported by the National Natural Science Foundation of China(42201319,42001281,42201347 and 42001324)the Guangdong Basic and Applied Basic Research Foundation(2023A1515011946 and 2023A1515011216)+1 种基金the Open Funding Project of the Key Laboratory of Marine Environmental Survey Technology and Application,Ministry of Natural Resources(MESTA-2021-B003)Independent Research Project of Guangming Laboratory Project:Moonshot Carbon Credit Rating Driven by AI and Remote Sensing Big Data(23400002)。
文摘China is experiencing accelerated urbanisation,with a large number of people moving from rural to urban areas[1].It has resulted in large losses in the net primary production(NPP),biodiversity and carbon stocks and an increase in environmental pollution and CO_(2)emissions[2–4].In 2015,196 countries signed the Paris Agreement and committed to setting long-term goals to jointly manage climate change and reduce their individual emissions,aiming to control the increase in global average temperature from the pre-industrial level to below 2℃and to curtail the temperature rise within 1.5℃till the end of the 21st century[5].China is bolstering its efforts to achieve the climate change mitigation goals and has announced a plan for achieving carbon neutrality by 2060[6].The carbon neutrality goal poses a challenge to the current policies promoting rapid urbanisation across China.
文摘Dear Editor,Tribe Andropogoneae within the family Poaceae encompasses92 genera and 1200 species of substantial agronomic and ecological importance,as represented by maize(Zea mays),sorghum(Sorghum bicolor),sugarcane(Saccharum officinarum),Miscanthus,and many other crops(Welker et al.,2020).
基金supported by the National Natural Science Foundation of China (61925504, 62192770, 62305252, 61621001, 62205246, 62020106009, 6201101335, 62205249, 62192772, 62192771)Shanghai Pilot Program for Basic Research, Science and Technology Commission of Shanghai Municipality (17JC1400800, 20JC1414600, 21JC1406100)+3 种基金the “Shu Guang” project supported by Shanghai Municipal Education Commission and Shanghai Education (17SG22)Shanghai Municipal Science and Technology Major Project (2021SHZDZX0100)Special Development Funds for Major Projects of Shanghai Zhangjiang National Independent Innovation Demonstration Zone (Grant No. ZJ2021-ZD-008)The Fundamental Research Funds for the Central Universities, Project funded by China Postdoctoral Science Foundation (2022M712401).
文摘Exceptional point (EP) is a special degeneracy of non-Hermitian systems. One-dimensional transmission systems operating at EPs are widely studied and applied to chiral conversion and sensing. Lately, two-dimensional systems at EPs have been exploited for their exotic scattering features, yet so far been limited to only the non-visible waveband. Here, we report a universal paradigm for achieving a high-efficiency EP in the visible by leveraging interlayer loss to accurately control the interplay between the lossy structure and scattering lightwaves. A bilayer framework is demonstrated to reflect back the incident light from the left side ( | r_(−1) | >0.999) and absorb the incident light from the right side ( | r_(+1) | < 10^(–4)). As a proof of concept, a bilayer metasurface is demonstrated to reflect and absorb the incident light with experimental efficiencies of 88% and 85%, respectively, at 532 nm. Our results open the way for a new class of nanoscale devices and power up new opportunities for EP physics.
基金supported by the National Natural Science Foundation of China(no.U1813207)the State Key Research Development Program of China(no.YS2022YFB3200011)+4 种基金Stabilization Support Program for Higher Education Institutions of Shenzhen(no.20200812115548001)Shenzhen Bay Laboratory Open Fund Project(no.SZBL2021080601012)High-end Talent Scientific Research Startup Project(no.827-000636)Shenzhen Science and Technology R&D and Innovation Foundation(no.JCJY20200109105608771)The authors acknowledge the support and funding of King Khalid University through Research Center for Advanced Materials Science(RCAMS)under grant no.RCAMS/KKU/0010/21.
文摘Infectious diseases severely threaten public health and global biosafety.In addition to transmission through the air,pathogenic microorganisms have also been detected in environmental liquid samples,such as sewage water.Conventional biochemical detection methodologies are time-consuming and cost-ineffective,and their detection limits hinder early diagnosis.In the present study,ultrafine plasmonic fiber probes with a diameter of 125μm are fabricated for clustered regularly interspaced short palindromic repeats/CRISPR-associated protein(CRISPR/Cas)-12a-mediated sensing of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Single-stranded DNA exposed on the fiber surface is trans-cleaved by the Cas12a enzyme to release gold nanoparticles that are immobilized onto the fiber surface,causing a sharp reduction in the surface plasmon resonance(SPR)wavelength.The proposed fiber probe is virus-specific with the limit of detection of~2,300 copies/ml,and genomic copy numbers can be reflected as shifts in wavelengths.A total of 21 sewage water samples have been examined,and the data obtained are consistent with those of quantitative polymerase chain reaction(qPCR).In addition,the Omicron variant and its mutation sites have been fast detected using S gene-specific Cas12a.This study provides an accurate and convenient approach for the real-time surveillance of microbial contamination in sewage water.
基金Supported by the National Natural Science Foundation of China(42122038,42375128,42275039,and 42075125)National Key Research and Development Program of China(2022YFC3701202)。
文摘The subject of“atmospheric radiation”includes not only fundamental theories on atmospheric gaseous absorption and the scattering and radiative transfer of particles(molecules,cloud,and aerosols),but also their applications in weather,climate,and atmospheric remote sensing,and is an essential part of the atmospheric sciences.This review includes two parts(Part I and PartⅡ);following the first part on gaseous absorption and particle scattering,this part(PartⅡ)reports the progress that has been made in radiative transfer theories,models,and their common applications,focusing particularly on the contributions from Chinese researchers.The recent achievements on radiative transfer models and methods developed for weather and climate studies and for atmospheric remote sensing are firstly reviewed.Then,the associated applications,such as surface radiation estimation,satellite remote sensing algorithms,radiative parameterization for climate models,and radiative-forcing related climate change studies are summarized,which further reveals the importance of radiative transfer theories and models.
基金National Research Foundation Singapore(PUB-1804-0082,NRF-CRP13-2014-01)Ministry of Education—Singapore(MOE2017-T3-1-001)。
文摘We demonstrate a smart sensor for label-free multicomponent chemical analysis using a single label-free ring resonator to acquire the entire resonant spectrum of the mixture and a neural network model to predict the composition for multicomponent analysis. The smart sensor shows a high prediction accuracy with a low rootmean-squared error ranging only from 0.13 to 2.28 mg/m L. The predicted concentrations of each component in the testing dataset almost all fall within the 95% prediction bands. With its simple label-free detection strategy and high accuracy, the smart sensor promises great potential for multicomponent analysis applications in many fields.
文摘Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free and bound forms were identified by liquid chromatography electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS)in both positive and negative modes.Further investigation of chemical constituents in the EtOAc extract led to the isolation of eleven individual compounds,and their chemical structures were identified as(−)-epicatechin(1),(−)-loliolide(2),(−)-syringaresinol-4-O-β-D-glucopyranoside(3),alloside of benzyl alcohol(4),3-[(6-O-hexopyranosylhexopyranosyl)oxy]-2-(palmitoyloxy)propyl(9Z,12Z,15Z)-9,12,15-octadecatrienoate(5),apocynoside I(6),quercetin-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucopyranoside(8),[1-acetyloxy-3-[3,4,5-trihydroxy-6-[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxymethyl]oxan-2-yl]oxypropan-2-yl]hexadecanoate(9),1-stearoyl-2-palmitoyl-sn-glycerol(10),and 3-hexene-l-O-β-D-glucoside(11)using a series of spectroscopic methods.Compounds 2–5 and 9–11 were isolated for the first time from A.venetum,while antioxidant experiments showed that compounds 1,7,and 8 displayed strong DPPH and ABTS+radical scavenging activities.This study represents the first investigation of bound phenolic compounds with potential health benefits in the residue of A.venetum tea.
