针对分布式光伏电站缺少专业监测、难以准确定位异常站点的问题,借助临近分布式光伏场站出力的相似性及相关性,提出一种基于核主成分分析-密度聚类(kernel principal component analysis-ordering points to identify the clustering st...针对分布式光伏电站缺少专业监测、难以准确定位异常站点的问题,借助临近分布式光伏场站出力的相似性及相关性,提出一种基于核主成分分析-密度聚类(kernel principal component analysis-ordering points to identify the clustering structure,KPCA-OPTICS)集群划分的分布式光伏功率异常感知方法。首先,基于光伏电站的出力数据,采用OPTICS算法对多场站进行集群划分,进而利用KPCA对聚类数据进行降维操作,以降低高维数据对OPTICS算法聚类准确性的影响。然后,以所划分的集群为目标进行异常感知处理,对集群不同天气下的出力进行等权重的加权平均,获得可以表征集群整体出力状况的出力曲线,并利用分位数回归(quantile regression,QR)拟合集群的出力区间,作为分布式光伏(distributed photovoltaic,DPV)集群的异常感知依据。最后,采用中国南方某城市分布式光伏数据集作为实际验证数据进行了仿真实验。结果表明:该方法能够有效地感知分布式光伏系统的功率异常,具有较高的检出率、精确率和较低的误报率,在实际部署中具有良好的模型扩展性。展开更多
Optical phase-gradient metasurfaces have garnered significant attention for enabling flexible light manipulation,with applications across diverse domains.In this work,we will demonstrate that the metasurfaces with pha...Optical phase-gradient metasurfaces have garnered significant attention for enabling flexible light manipulation,with applications across diverse domains.In this work,we will demonstrate that the metasurfaces with phase gradient modulation can be used to achieve illusion optics,featuring the advantages of simple geometric structure and feasible implementation compared with the well-known transformation optics method.The underlying mechanism is the anomalous diffraction law caused by the phase gradient,which provides a theoretical basis for freely manipulating the propagation path of light.By considering a specific example,we will demonstrate that the phase gradient can transform spatial coordinates in real space into illusion space,thereby converting a plane in real space into a curved surface structure in illusion space to achieve the illusion effect.This approach provides a viable alternative to transformation optics for designing illusion devices.展开更多
Cells interact with the extracellular matrix and generate traction forces,which play fundamental roles in many cytological activities,such as migration and differentiation.The quanti fication of these traction forces ...Cells interact with the extracellular matrix and generate traction forces,which play fundamental roles in many cytological activities,such as migration and differentiation.The quanti fication of these traction forces is a prerequisite for understanding the interaction and regulation between force and functions,which can be accomplished by traction force microscopy(TFM).In TFM,the forces are determined by tracking the displacement of fiducial markers through optical microscopy.The type of fiducial marker,microscopy modality,and image processing algorithms are key factors determining the final resolution of TFM.This review summarizes efforts in three aspects to enhance the performance of TFM and discusses the challenges of further development,particularly from an optical view.展开更多
The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflect...The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflectivity observed by GPM Ku PR is compared quantitatively against GR networks from CINRAD of China and NEXRAD of the United States,and the volume matching method is used for spatial matching.Additionally,a novel frequency correction method for all phases as well as precipitation types is used to correct the GPM Ku PR radar frequency to the GR frequency.A total of 20 GRs(including 10 from CINRAD and 10 from NEXRAD)are included in this comparative analysis.The results indicate that,compared with CINRAD matched data,NEXRAD exhibits larger biases in reflectivity when compared with the frequency-corrected Ku PR.The root-mean-square difference for CINRAD is calculated at 2.38 d B,whereas for NEXRAD it is 3.23 d B.The mean bias of CINRAD matched data is-0.16 d B,while the mean bias of NEXRAD is-2.10 d B.The mean standard deviation of bias for CINRAD is 2.15 d B,while for NEXRAD it is 2.29 d B.This study effectively assesses weather radar data in both the United States and China,which is crucial for improving the overall consistency of global precipitation estimates.展开更多
Aerosol optical properties from August 2006 to July 2007 were obtained from ground-based and sky radiance measurements in Semi- Arid Climate and Environment Observatory of Lanzhou University （SACOL）, China. High aer...Aerosol optical properties from August 2006 to July 2007 were obtained from ground-based and sky radiance measurements in Semi- Arid Climate and Environment Observatory of Lanzhou University （SACOL）, China. High aerosol optical thickness （AOT） associated with low .Angstrom exponent （α） was mainly observed in spring, which was consistent with the seasonal dust production from Hexi Corridor. The maximum monthly average value of AOT 0.56 occurred in March of 2007, which was two times larger than the minimum value of 0.28 in October of 2006. Approximately 60% of the AOT ranged between 0.3 and 0.5, and nearly 93% ofα value varied from 0.1 to 0.8, which occurred in spring. The significant correlation between aerosol properties and water vapor content was not observed. The aerosol volume size distribution can be characterized by the bimodal logarithm normal structure： fine mode （r 〈 0.6 μm） and coarse mode （r 〉 0.6 μm）. Aerosols in spring of SACOL were dominated by large particles with the volume concentration ratio of coarse to fine modes being 7.85. The average values of asymmetry factor （g） in the wavelength range 440-1020 nm were found to be 0.71, 0.67, 0.67 and 0.69 in spring, summer, autumn and winter, respectively.展开更多
Space target imaging simulation technology is an important tool for space target detection and identification,with advantages that include high flexibility and low cost.However,existing space target imaging simulation...Space target imaging simulation technology is an important tool for space target detection and identification,with advantages that include high flexibility and low cost.However,existing space target imaging simulation technologies are mostly based on target magnitudes for simulations,making it difficult to meet image simulation requirements for different signal-to-noise ratio(SNR)needs.Therefore,design of a simulation method that generates target image sequences with various SNRs based on the optical detection system parameters will be important for faint space target detection research.Addressing the SNR calculation issue in optical observation systems,this paper proposes a ground-based detection image SNR calculation method using the optical system parameters.This method calculates the SNR of an observed image precisely using radiative transfer theory,the optical system parameters,and the observation environment parameters.An SNR-based target sequence image simulation method for ground-based detection scenarios is proposed.This method calculates the imaging SNR using the optical system parameters and establishes a model for conversion between the target’s apparent magnitude and image grayscale values,thereby enabling generation of target sequence simulation images with corresponding SNRs for different system parameters.Experiments show that the SNR obtained using this calculation method has an average calculation error of<1 dB when compared with the theoretical SNR of the actual optical system.Additionally,the simulation images generated by the imaging simulation method show high consistency with real images,which meets the requirements of faint space target detection algorithm research and provides reliable data support for development of related technologies.展开更多
Object imaging beyond the direct line of sight is significant for applications in robotic vision,remote sensing,autonomous driving,and many other areas.Reconstruction of a non-line-of-sight(NLOS)screen is a complex in...Object imaging beyond the direct line of sight is significant for applications in robotic vision,remote sensing,autonomous driving,and many other areas.Reconstruction of a non-line-of-sight(NLOS)screen is a complex inverse problem that comes with ultrafast time-resolved imager requirements and substantial computational demands to extract information from the multi-bounce scattered light.Consequently,the echo signal always suffers from serious deterioration in both intensity and shape,leading to limited resolution and image contrast.Here,we propose a concept of vectorial digitelligent optics for high-resolution NLOS imaging to cancel the wall’s scattering and refocus the light onto hidden targets for enhanced echo.In this approach,the polarization and wavefront of the laser spot are intelligently optimized via a feedback algorithm to form a near-perfect focusing pattern through a random scattering wall.By raster scanning the focusing spot across the object’s surface within the optical-memory-effect range of the wall,we obtain nearly diffraction-limited NLOS imaging with an enhanced signal-to-noise ratio.Our experimental results demonstrate a resolution of 0.40 mm at a distance of 0.35 m,reaching the diffraction limit of the system.Furthermore,we demonstrate that the proposed method is feasible for various complex NLOS scenarios.Our methods may open an avenue for active imaging,communication,and laser wireless power transfer.展开更多
The second near-infrared window(NIR-II,900-1880 nm)overcomes critical limitations of visible(360-760 nm)and NIR-I(760-900 nm)imaging—including restricted penetration depth,low signal-to-back⁃ground ratio,and tissue a...The second near-infrared window(NIR-II,900-1880 nm)overcomes critical limitations of visible(360-760 nm)and NIR-I(760-900 nm)imaging—including restricted penetration depth,low signal-to-back⁃ground ratio,and tissue autofluorescence—establishing its pivotal role for in vivo deep-tissue bioimaging.With exponential growth in NIR-II photodiagnosis and phototherapy research over the past decade,bibliometric analy⁃sis is essential to map the evolving landscape and guide strategic priorities.We systematically analyzed 2,491 NIR-II-related publications(2009-2023)from the Web of Science Core Collection,employing scientometric tools for distinct analytical purposes:(a)VOSviewer,SCImago Graphica,and Gephi for co-authorship and co-occur⁃rence network mapping;(b)the R bibliometrix package for tracking field evolution and identifying high-impact publications/journals.The search retrieved 2491 studies from 359 journals originating from 54 countries.The country with the most published articles is China.Chinese institutions drive>60%of publications,with Stanford University(USA)and Nanyang Technological University(Singapore)ranked as the top two institutions by re⁃search quality.International cooperation is becoming increasingly frequent.Fan Quli,Tang Benzhong and Dai Hongjie are the top 3 productive authors in this field.Keyword evolution identifies"photodynamic therapy"and"immunotherapy"as pivotal future directions.We summarize the most cited literatures and NIR-II imaging clini⁃cal trials.This study delineates the NIR-II research trajectory,highlighting China's leadership,intensifying glob⁃al collaboration,and interdisciplinary convergence.Future efforts should prioritize the novel NIR-II probe devel⁃opment for NIR-II imaging and clinical translation of photodynamic/immunotherapy combinational platforms.展开更多
Accurate cloud classification plays a crucial role in aviation safety,climate monitoring,and localized weather forecasting.Current research has been focusing on machine learning techniques,particularly deep learning b...Accurate cloud classification plays a crucial role in aviation safety,climate monitoring,and localized weather forecasting.Current research has been focusing on machine learning techniques,particularly deep learning based model,for the types identification.However,traditional approaches such as convolutional neural networks(CNNs)encounter difficulties in capturing global contextual information.In addition,they are computationally expensive,which restricts their usability in resource-limited environments.To tackle these issues,we present the Cloud Vision Transformer(CloudViT),a lightweight model that integrates CNNs with Transformers.The integration enables an effective balance between local and global feature extraction.To be specific,CloudViT comprises two innovative modules:Feature Extraction(E_Module)and Downsampling(D_Module).These modules are able to significantly reduce the number of model parameters and computational complexity while maintaining translation invariance and enhancing contextual comprehension.Overall,the CloudViT includes 0.93×10^(6)parameters,which decreases more than ten times compared to the SOTA(State-of-the-Art)model CloudNet.Comprehensive evaluations conducted on the HBMCD and SWIMCAT datasets showcase the outstanding performance of CloudViT.It achieves classification accuracies of 98.45%and 100%,respectively.Moreover,the efficiency and scalability of CloudViT make it an ideal candidate for deployment inmobile cloud observation systems,enabling real-time cloud image classification.The proposed hybrid architecture of CloudViT offers a promising approach for advancing ground-based cloud image classification.It holds significant potential for both optimizing performance and facilitating practical deployment scenarios.展开更多
Fourier Ptychographic Microscopy(FPM)is a high-throughput computational optical imaging technology reported in 2013.It effectively breaks through the trade-off between high-resolution imaging and wide-field imaging.In...Fourier Ptychographic Microscopy(FPM)is a high-throughput computational optical imaging technology reported in 2013.It effectively breaks through the trade-off between high-resolution imaging and wide-field imaging.In recent years,it has been found that FPM is not only a tool to break through the trade-off between field of view and spatial resolution,but also a paradigm to break through those trade-off problems,thus attracting extensive attention.Compared with previous reviews,this review does not introduce its concept,basic principles,optical system and series of applications once again,but focuses on elaborating the three major difficulties faced by FPM technology in the process from“looking good”in the laboratory to“working well”in practical applications:mismatch between numerical model and physical reality,long reconstruction time and high computing power demand,and lack of multi-modal expansion.It introduces how to achieve key technological innovations in FPM through the dual drive of Artificial Intelligence(AI)and physics,including intelligent reconstruction algorithms introducing machine learning concepts,optical-algorithm co-design,fusion of frequency domain extrapolation methods and generative adversarial networks,multi-modal imaging schemes and data fusion enhancement,etc.,gradually solving the difficulties of FPM technology.Conversely,this review deeply considers the unique value of FPM technology in potentially feeding back to the development of“AI+optics”,such as providing AI benchmark tests under physical constraints,inspirations for the balance of computing power and bandwidth in miniaturized intelligent microscopes,and photoelectric hybrid architectures.Finally,it introduces the industrialization path and frontier directions of FPM technology,pointing out that with the promotion of the dual drive of AI and physics,it will generate a large number of industrial application case,and looks forward to the possibilities of future application scenarios and expansions,for instance,body fluid biopsy and point-of-care testing at the grassroots level represent the expansion of the growth market.展开更多
Adaptive optics(AO)has significantly advanced high-resolution solar observations by mitigating atmospheric turbulence.However,traditional post-focal AO systems suffer from external configurations that introduce excess...Adaptive optics(AO)has significantly advanced high-resolution solar observations by mitigating atmospheric turbulence.However,traditional post-focal AO systems suffer from external configurations that introduce excessive optical surfaces,reduced light throughput,and instrumental polarization.To address these limitations,we propose an embedded solar adaptive optics telescope(ESAOT)that intrinsically incorporates the solar AO(SAO)subsystem within the telescope's optical train,featuring a co-designed correction chain with a single Hartmann-Shack full-wavefront sensor(HS f-WFS)and a deformable secondary mirror(DSM).The HS f-WFS uses temporal-spatial hybrid sampling technique to simultane-ously resolve tip-tilt and high-order aberrations,while the DSM performs real-time compensation through adaptive modal optimization.This unified architecture achieves symmetrical polarization suppression and high system throughput by min-imizing optical surfaces.A 600 mm ESAOT prototype incorporating a 12×12 micro-lens array HS f-WFS and 61-actuator piezoelectric DSM has been developed and successfully conducted on-sky photospheric observations.Validations in-cluding turbulence simulations,optical bench testing,and practical observations at the Lijiang observatory collectively confirm the system's capability to maintain aboutλ/10 wavefront error during active region tracking.This architectural breakthrough of the ESAOT addresses long-standing SAO integration challenges in solar astronomy and provides scala-bility analyses confirming direct applicability to the existing and future large solar observation facilities.展开更多
The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly a...The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly applicable optical trapping system based on a custom-designed 2×3 optical tweezer array,which enables the real-time interception and manipulation of circulating leukocytes in live animals.By utilizing intrinsic velocity differences between leukocytes and red blood cells,the system achieves stable trapping of individual leukocytes in vessels 15-20μm in diameter and decelerates multiple cells in vessels greater than 20μm.Notably,it also enables the optical blockage of lymphatic vessels exceeding 50μm,a previously unreported capability.This label-free,noninvasive approach operates without repeated blood draws and is compatible with diverse vessel geometries and flow dynamics.The system offers a generalizable solution for in vivo cell extraction and analysis,paving the way for high-precision single-cell technologies in biomedical research and clinical translation.展开更多
A differential optical absorption spectroscopy （DOAS）-like algorithm is developed to retrieve the column-averaged dry- air mole fraction of carbon dioxide from ground-based hyper-spectral measurements of the direct ...A differential optical absorption spectroscopy （DOAS）-like algorithm is developed to retrieve the column-averaged dry- air mole fraction of carbon dioxide from ground-based hyper-spectral measurements of the direct solar beam. Different to the spectral fitting method, which minimizes the difference between the observed and simulated spectra, the ratios of multiple channel-pairs--one weak and one strong absorption channel--are used to retrieve Xc02 from measurements of the shortwave infrared （SWIR） band. Based on sensitivity tests, a super channel-pair is carefully selected to reduce the effects of solar lines, water vapor, air temperature, pressure, instrument noise, and frequency shift on retrieval errors. The new algorithm reduces computational cost and the retrievals are le^s sensitive to temperature and H20 uncertainty than the spectral fitting method. Multi-day Total Carbon Column Observing Network （TCCON） measurements under clear-sky conditions at two sites （Tsukuba and Bremen） are used to derive Xc02 for the algorithm evaluation and validation. The DOAS-like results agree very well with those of the TCCON algorithm after correction of an airmass-dependent bias.展开更多
The field of subwavelength optics has opened new avenues for investigating light–matter interactions by enabling the exploration of novel phenomena at the subwavelength scale. In recent decades,advancements in fundam...The field of subwavelength optics has opened new avenues for investigating light–matter interactions by enabling the exploration of novel phenomena at the subwavelength scale. In recent decades,advancements in fundamental understanding and micro–nanotechnologies have significantly propelled the development of subwavelength optics and its practical applications.展开更多
Manufacturing-robust imaging systems leveraging computational optics hold immense potential for easing manufacturing constraints and enabling the development of cost-effective,high-quality imaging solutions.However,co...Manufacturing-robust imaging systems leveraging computational optics hold immense potential for easing manufacturing constraints and enabling the development of cost-effective,high-quality imaging solutions.However,conventional approaches,which typically rely on data-driven neural networks to correct optical aberrations caused by manufacturing errors,are constrained by the lack of effective tolerance analysis methods for quantitatively evaluating manufacturing error boundaries.This limitation is crucial for further relaxing manufacturing constraints and providing practical guidance for fabrication.We propose a physics-informed design paradigm for manufacturing-robust imaging systems with computational optics,integrating a physics-informed tolerance analysis methodology for evaluating manufacturing error boundaries and a physics-informed neural network for image reconstruction.With this approach,we achieve a manufacturing-robust imaging system based on an off-axis three-mirror freeform all-aluminum design,delivering a modulation transfer function exceeding 0.34 at the Nyquist frequency(72 lp/mm)in simulation.Notably,this system requires a manufacturing precision of only 0.5λin root mean square(RMS),representing a remarkable 25-fold relaxation compared with the conventional requirement of 0.02λin RMS.Experimental validation further confirmed that the manufacturing-robust imaging system maintains excellent performance in diverse indoor and outdoor environments.Our proposed method paves the way for achieving high-quality imaging without the necessity of high manufacturing precision,enabling practical solutions that are more cost-effective and time-efficient.展开更多
I shall deserve the Reputation of having beene ye first to lay the grounds of two Sciences,"wrote Thomas Hobbes in 1646,"this of Optiques and yt other of natural Justice."For him,optics and politics wer...I shall deserve the Reputation of having beene ye first to lay the grounds of two Sciences,"wrote Thomas Hobbes in 1646,"this of Optiques and yt other of natural Justice."For him,optics and politics were two prongs of the same effort:to naturalize humans’relations to their world and to each other.It was Descartes’Dioptrique,handed to him by Kenelm Digby in 1637,that cleared for him the path:naturalizing humans required physicalizing vision–as Kepler taught in his own optics–and removing from nature of all cognitive entities such as"species visible and intelligible."Between 1639 and 1646 Hobbes produced three professional,innovative treatises on optics founded upon"the opinion of the excellent Monsieur Des Cartes"but,finally,diverging from it in the most crucial point.For Descartes,ridding"Matter[of all]such Descriptions…as belong but to Spiritual Beings"required a spiritual,non-material entity to interpret the physical effects of the senses.Hobbes,however,insisted that the interpretation can and should be understood physically and mechanically,for"Vision is the judgement itself.展开更多
AIM:To assess the variations in photoreceptor cell packing density(PCPD)across the retina among young healthy individuals with emmetropia,low and moderate myopia.METHODS:High-resolution adaptive optics scanning laser ...AIM:To assess the variations in photoreceptor cell packing density(PCPD)across the retina among young healthy individuals with emmetropia,low and moderate myopia.METHODS:High-resolution adaptive optics scanning laser ophthalmoscopy(AOSLO)systems were utilized for retinal imaging with a large sampling window of 700μm×700μm.The study cohort included 14 emmetropic[spherical equivalent(SE)ranged+0.5 to-0.5 D],15 low myopic(SE ranged-0.5 to-3 D)and 21 moderate myopic(SE ranged-3 to-6 D)healthy young adults.Photoreceptors at 3°temporal,6°superior and inferior 6°were captured.Statistical analysis was then performed to obtain PCPD and cell spacing.RESULTS:The average age of participants was 22.54±2.86(ranged 20–30y)with no difference among 3 groups.At 3°temporal,the emmetropic group exhibited the highest PCPD of 15186.16±2050.54 cells/mm^(2),while the low and moderate myopic groups had PCPD of 14009.15±1073.01 and 13466.92±1121.71 cells/mm2,respectively.At 3°temporal,the emmetropic group also had the smallest cell spacing at 6.66±0.26 mm,compared to 6.85±0.26 and 6.91±0.28 mm for the low and moderate myopic groups,respectively.Compared to the emmetropic group,at 3°temporal,the myopic groups showed significantly reduced PCPD(low myopia:P=0.032;moderate myopia:P=0.001).At 6°inferior,the moderate myopic group exhibited a significant decrease in PCPD(P=0.013),while at 6°superior,there were no significant statistical differences in PCPD for the low and moderate myopic groups(P>0.05).In comparison to the emmetropic group,only the moderate myopic group showed significantly increased cell spacing at all three positions(temporal 3°:P=0.011,superior 6°:P=0.046,inferior 6°:P=0.013).Correlation analysis revealed a positive correlation between PCPD and axial length changes(P<0.05).CONCLUSION:Reduced PCPD and increased cell spacing strongly correlated with refractive error in mild to moderate myopic eyes,especially at 6°inferior to the fovea and the decreased PCPD in the macular region of myopic patients may be associated with increased axial lengthinduced retinal stretching.展开更多
Multi-axial differential optical absorption spectroscopy(MAX-DOAS)measurements were conducted in Xishuangbanna,Yunnan,China,between November 1,2021 and June 30,2022 to obtain vertical distributions of formaldehyde(HCH...Multi-axial differential optical absorption spectroscopy(MAX-DOAS)measurements were conducted in Xishuangbanna,Yunnan,China,between November 1,2021 and June 30,2022 to obtain vertical distributions of formaldehyde(HCHO)and glyoxal(CHOCHO).The observations show an increase in vertical column densities(VCDs)and volume mixing ratios(VMRs)for both HCHO and CHOCHO concentrations during periods of biomass combustion.The VCDs of HCHO and CHOCHO from TROPOMI are in good agreementwith the MAX-DOAS observations.(R^(2) HCHO=0.71;R^(2) CHOCHO=0.70).Regarding seasonal variations,HCHO predominantly occupies the upper layer(400-800 m)during the biomass burning,possibly attributed to the formation of secondary HCHO as the plume ascends during combustion.CHOCHO is primarily found in the lower layer(0-200 m),suggesting a longer lifespan for HCHO compared to CHOCHO,preventing the latter from diffusing to higher altitudes.Concerning the daily variation patterns,both HCHO and CHOCHO VMRs exhibited peaks at 9:00 and 13:00,which were attributed to the nighttime accumulation and midday oxidation.Furthermore,we also investigated the sources of volatile organic compounds(VOCs)using the CHOCHO to HCHO ratio(RGF).During the period of biomass burning,there are minimal differences in the daily RGF across layers,indicating that biomass burning is the predominant source.During the non-biomass burning period,the daily RGF shows significant differences among layers,indicating that emissions from biological and anthropogenic sources primarily contribute during the period.展开更多
We report the SrII optical lattice clock at the National Time Service Center(NTSC).In this system,a blackbody radiation shield with movable lattice mitigates blackbody radiation shifts through active temperature contr...We report the SrII optical lattice clock at the National Time Service Center(NTSC).In this system,a blackbody radiation shield with movable lattice mitigates blackbody radiation shifts through active temperature control.A shallow optical lattice with minimal tunneling minimizes AC Stark shifts.Phase-locked counter-propagating lattice beams and conductive vacuum viewports further reduce systematic uncertainties and a novel initial-state preparation method simplifies the system.Clock transition spectra achieve a linewidth of 2.5 Hz with a 400 ms clock pulse,and self-comparison stability reaches 5.1×10^(-16)at 1 s.These advancements give this clock the potential to be a critical platform for realizing outstanding systematic uncertainties in the future.展开更多
文摘针对分布式光伏电站缺少专业监测、难以准确定位异常站点的问题,借助临近分布式光伏场站出力的相似性及相关性,提出一种基于核主成分分析-密度聚类(kernel principal component analysis-ordering points to identify the clustering structure,KPCA-OPTICS)集群划分的分布式光伏功率异常感知方法。首先,基于光伏电站的出力数据,采用OPTICS算法对多场站进行集群划分,进而利用KPCA对聚类数据进行降维操作,以降低高维数据对OPTICS算法聚类准确性的影响。然后,以所划分的集群为目标进行异常感知处理,对集群不同天气下的出力进行等权重的加权平均,获得可以表征集群整体出力状况的出力曲线,并利用分位数回归(quantile regression,QR)拟合集群的出力区间,作为分布式光伏(distributed photovoltaic,DPV)集群的异常感知依据。最后,采用中国南方某城市分布式光伏数据集作为实际验证数据进行了仿真实验。结果表明:该方法能够有效地感知分布式光伏系统的功率异常,具有较高的检出率、精确率和较低的误报率,在实际部署中具有良好的模型扩展性。
基金supported by the National Natural Science Foundation of China (Grant Nos.12274313 and 62375234)the Gusu Leading Talent Plan for Scientific and Technological Innovation and Entrepreneurship (Grant No.ZXL2024400)。
文摘Optical phase-gradient metasurfaces have garnered significant attention for enabling flexible light manipulation,with applications across diverse domains.In this work,we will demonstrate that the metasurfaces with phase gradient modulation can be used to achieve illusion optics,featuring the advantages of simple geometric structure and feasible implementation compared with the well-known transformation optics method.The underlying mechanism is the anomalous diffraction law caused by the phase gradient,which provides a theoretical basis for freely manipulating the propagation path of light.By considering a specific example,we will demonstrate that the phase gradient can transform spatial coordinates in real space into illusion space,thereby converting a plane in real space into a curved surface structure in illusion space to achieve the illusion effect.This approach provides a viable alternative to transformation optics for designing illusion devices.
基金supported by the Major Research Instrument Development Project of the National Natural Science Foundation of China(32527801)the National Natural Science Foundation of China(32301168)+1 种基金the Ningbo Natural Science Foundation of China(2023J351)the Yongjiang Innovative Talents Project of Ningbo City(2024A-172-G).
文摘Cells interact with the extracellular matrix and generate traction forces,which play fundamental roles in many cytological activities,such as migration and differentiation.The quanti fication of these traction forces is a prerequisite for understanding the interaction and regulation between force and functions,which can be accomplished by traction force microscopy(TFM).In TFM,the forces are determined by tracking the displacement of fiducial markers through optical microscopy.The type of fiducial marker,microscopy modality,and image processing algorithms are key factors determining the final resolution of TFM.This review summarizes efforts in three aspects to enhance the performance of TFM and discusses the challenges of further development,particularly from an optical view.
基金funded by the National Key Research and Development Program of China(Grant No.2023YFB3907500)the National Natural Science Foundation(Grant No.42330602)the“Fengyun Satellite Remote Sensing Product Validation and Verification”Youth Innovation Team of the China Meteorological Administration(Grant No.CMA2023QN12)。
文摘The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflectivity observed by GPM Ku PR is compared quantitatively against GR networks from CINRAD of China and NEXRAD of the United States,and the volume matching method is used for spatial matching.Additionally,a novel frequency correction method for all phases as well as precipitation types is used to correct the GPM Ku PR radar frequency to the GR frequency.A total of 20 GRs(including 10 from CINRAD and 10 from NEXRAD)are included in this comparative analysis.The results indicate that,compared with CINRAD matched data,NEXRAD exhibits larger biases in reflectivity when compared with the frequency-corrected Ku PR.The root-mean-square difference for CINRAD is calculated at 2.38 d B,whereas for NEXRAD it is 3.23 d B.The mean bias of CINRAD matched data is-0.16 d B,while the mean bias of NEXRAD is-2.10 d B.The mean standard deviation of bias for CINRAD is 2.15 d B,while for NEXRAD it is 2.29 d B.This study effectively assesses weather radar data in both the United States and China,which is crucial for improving the overall consistency of global precipitation estimates.
基金supported by the National Basic Research Program (973) of China (No. 2006CB403706)the National Natural Science Foundation of China (No.40875078)+2 种基金the Key Basic Research Program of Natural Science for University of Jiangsu (No. 08KJA170002)the Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information Scienceand Technology (No. KLME20060302, KLME060209,KLME0907)the Shanghai Tongji Gao Tingyao Environmental Science & Technology Development Foundation
文摘Aerosol optical properties from August 2006 to July 2007 were obtained from ground-based and sky radiance measurements in Semi- Arid Climate and Environment Observatory of Lanzhou University （SACOL）, China. High aerosol optical thickness （AOT） associated with low .Angstrom exponent （α） was mainly observed in spring, which was consistent with the seasonal dust production from Hexi Corridor. The maximum monthly average value of AOT 0.56 occurred in March of 2007, which was two times larger than the minimum value of 0.28 in October of 2006. Approximately 60% of the AOT ranged between 0.3 and 0.5, and nearly 93% ofα value varied from 0.1 to 0.8, which occurred in spring. The significant correlation between aerosol properties and water vapor content was not observed. The aerosol volume size distribution can be characterized by the bimodal logarithm normal structure： fine mode （r 〈 0.6 μm） and coarse mode （r 〉 0.6 μm）. Aerosols in spring of SACOL were dominated by large particles with the volume concentration ratio of coarse to fine modes being 7.85. The average values of asymmetry factor （g） in the wavelength range 440-1020 nm were found to be 0.71, 0.67, 0.67 and 0.69 in spring, summer, autumn and winter, respectively.
基金supported by Open Fund of National Key Laboratory of Deep Space Exploration(NKDSEL2024014)by Civil Aerospace Pre-research Project of State Administration of Science,Technology and Industry for National Defence,PRC(D040103).
文摘Space target imaging simulation technology is an important tool for space target detection and identification,with advantages that include high flexibility and low cost.However,existing space target imaging simulation technologies are mostly based on target magnitudes for simulations,making it difficult to meet image simulation requirements for different signal-to-noise ratio(SNR)needs.Therefore,design of a simulation method that generates target image sequences with various SNRs based on the optical detection system parameters will be important for faint space target detection research.Addressing the SNR calculation issue in optical observation systems,this paper proposes a ground-based detection image SNR calculation method using the optical system parameters.This method calculates the SNR of an observed image precisely using radiative transfer theory,the optical system parameters,and the observation environment parameters.An SNR-based target sequence image simulation method for ground-based detection scenarios is proposed.This method calculates the imaging SNR using the optical system parameters and establishes a model for conversion between the target’s apparent magnitude and image grayscale values,thereby enabling generation of target sequence simulation images with corresponding SNRs for different system parameters.Experiments show that the SNR obtained using this calculation method has an average calculation error of<1 dB when compared with the theoretical SNR of the actual optical system.Additionally,the simulation images generated by the imaging simulation method show high consistency with real images,which meets the requirements of faint space target detection algorithm research and provides reliable data support for development of related technologies.
基金supported by the National Key Research and Development Program of China(2023YFB2805800 and 2021YFA1401003)the National Natural Science Foundation of China(62222513).
文摘Object imaging beyond the direct line of sight is significant for applications in robotic vision,remote sensing,autonomous driving,and many other areas.Reconstruction of a non-line-of-sight(NLOS)screen is a complex inverse problem that comes with ultrafast time-resolved imager requirements and substantial computational demands to extract information from the multi-bounce scattered light.Consequently,the echo signal always suffers from serious deterioration in both intensity and shape,leading to limited resolution and image contrast.Here,we propose a concept of vectorial digitelligent optics for high-resolution NLOS imaging to cancel the wall’s scattering and refocus the light onto hidden targets for enhanced echo.In this approach,the polarization and wavefront of the laser spot are intelligently optimized via a feedback algorithm to form a near-perfect focusing pattern through a random scattering wall.By raster scanning the focusing spot across the object’s surface within the optical-memory-effect range of the wall,we obtain nearly diffraction-limited NLOS imaging with an enhanced signal-to-noise ratio.Our experimental results demonstrate a resolution of 0.40 mm at a distance of 0.35 m,reaching the diffraction limit of the system.Furthermore,we demonstrate that the proposed method is feasible for various complex NLOS scenarios.Our methods may open an avenue for active imaging,communication,and laser wireless power transfer.
基金Supported by National Natural Science Foundation of China(81874059 and 82102105)the Natural Science Foundation of Zhejiang Province(LQ22H160017)the China Postdoctoral Science Foundation(2021M702825).
文摘The second near-infrared window(NIR-II,900-1880 nm)overcomes critical limitations of visible(360-760 nm)and NIR-I(760-900 nm)imaging—including restricted penetration depth,low signal-to-back⁃ground ratio,and tissue autofluorescence—establishing its pivotal role for in vivo deep-tissue bioimaging.With exponential growth in NIR-II photodiagnosis and phototherapy research over the past decade,bibliometric analy⁃sis is essential to map the evolving landscape and guide strategic priorities.We systematically analyzed 2,491 NIR-II-related publications(2009-2023)from the Web of Science Core Collection,employing scientometric tools for distinct analytical purposes:(a)VOSviewer,SCImago Graphica,and Gephi for co-authorship and co-occur⁃rence network mapping;(b)the R bibliometrix package for tracking field evolution and identifying high-impact publications/journals.The search retrieved 2491 studies from 359 journals originating from 54 countries.The country with the most published articles is China.Chinese institutions drive>60%of publications,with Stanford University(USA)and Nanyang Technological University(Singapore)ranked as the top two institutions by re⁃search quality.International cooperation is becoming increasingly frequent.Fan Quli,Tang Benzhong and Dai Hongjie are the top 3 productive authors in this field.Keyword evolution identifies"photodynamic therapy"and"immunotherapy"as pivotal future directions.We summarize the most cited literatures and NIR-II imaging clini⁃cal trials.This study delineates the NIR-II research trajectory,highlighting China's leadership,intensifying glob⁃al collaboration,and interdisciplinary convergence.Future efforts should prioritize the novel NIR-II probe devel⁃opment for NIR-II imaging and clinical translation of photodynamic/immunotherapy combinational platforms.
基金funded by Innovation and Development Special Project of China Meteorological Administration(CXFZ2022J038,CXFZ2024J035)Sichuan Science and Technology Program(No.2023YFQ0072)+1 种基金Key Laboratory of Smart Earth(No.KF2023YB03-07)Automatic Software Generation and Intelligent Service Key Laboratory of Sichuan Province(CUIT-SAG202210).
文摘Accurate cloud classification plays a crucial role in aviation safety,climate monitoring,and localized weather forecasting.Current research has been focusing on machine learning techniques,particularly deep learning based model,for the types identification.However,traditional approaches such as convolutional neural networks(CNNs)encounter difficulties in capturing global contextual information.In addition,they are computationally expensive,which restricts their usability in resource-limited environments.To tackle these issues,we present the Cloud Vision Transformer(CloudViT),a lightweight model that integrates CNNs with Transformers.The integration enables an effective balance between local and global feature extraction.To be specific,CloudViT comprises two innovative modules:Feature Extraction(E_Module)and Downsampling(D_Module).These modules are able to significantly reduce the number of model parameters and computational complexity while maintaining translation invariance and enhancing contextual comprehension.Overall,the CloudViT includes 0.93×10^(6)parameters,which decreases more than ten times compared to the SOTA(State-of-the-Art)model CloudNet.Comprehensive evaluations conducted on the HBMCD and SWIMCAT datasets showcase the outstanding performance of CloudViT.It achieves classification accuracies of 98.45%and 100%,respectively.Moreover,the efficiency and scalability of CloudViT make it an ideal candidate for deployment inmobile cloud observation systems,enabling real-time cloud image classification.The proposed hybrid architecture of CloudViT offers a promising approach for advancing ground-based cloud image classification.It holds significant potential for both optimizing performance and facilitating practical deployment scenarios.
基金National Natural Science Foundation of China(No.12574332)the Space Optoelectronic Measurement and Perception Lab.,Beijing Institute of Control Engineering(No.LabSOMP-2023-10)Major Science and Technology Innovation Program of Xianyang City(No.L2024-ZDKJ-ZDCGZH-0021)。
文摘Fourier Ptychographic Microscopy(FPM)is a high-throughput computational optical imaging technology reported in 2013.It effectively breaks through the trade-off between high-resolution imaging and wide-field imaging.In recent years,it has been found that FPM is not only a tool to break through the trade-off between field of view and spatial resolution,but also a paradigm to break through those trade-off problems,thus attracting extensive attention.Compared with previous reviews,this review does not introduce its concept,basic principles,optical system and series of applications once again,but focuses on elaborating the three major difficulties faced by FPM technology in the process from“looking good”in the laboratory to“working well”in practical applications:mismatch between numerical model and physical reality,long reconstruction time and high computing power demand,and lack of multi-modal expansion.It introduces how to achieve key technological innovations in FPM through the dual drive of Artificial Intelligence(AI)and physics,including intelligent reconstruction algorithms introducing machine learning concepts,optical-algorithm co-design,fusion of frequency domain extrapolation methods and generative adversarial networks,multi-modal imaging schemes and data fusion enhancement,etc.,gradually solving the difficulties of FPM technology.Conversely,this review deeply considers the unique value of FPM technology in potentially feeding back to the development of“AI+optics”,such as providing AI benchmark tests under physical constraints,inspirations for the balance of computing power and bandwidth in miniaturized intelligent microscopes,and photoelectric hybrid architectures.Finally,it introduces the industrialization path and frontier directions of FPM technology,pointing out that with the promotion of the dual drive of AI and physics,it will generate a large number of industrial application case,and looks forward to the possibilities of future application scenarios and expansions,for instance,body fluid biopsy and point-of-care testing at the grassroots level represent the expansion of the growth market.
基金support from the National Science Foundation of China(NSFC)(Grants No.12293031 and No.61905252)the National Science Foundation for Distinguished Young Scholars(Grant No.12022308)the National Key R&D Program of China(Grants No.2021YFC2202200 and No.2021YFC2202204).
文摘Adaptive optics(AO)has significantly advanced high-resolution solar observations by mitigating atmospheric turbulence.However,traditional post-focal AO systems suffer from external configurations that introduce excessive optical surfaces,reduced light throughput,and instrumental polarization.To address these limitations,we propose an embedded solar adaptive optics telescope(ESAOT)that intrinsically incorporates the solar AO(SAO)subsystem within the telescope's optical train,featuring a co-designed correction chain with a single Hartmann-Shack full-wavefront sensor(HS f-WFS)and a deformable secondary mirror(DSM).The HS f-WFS uses temporal-spatial hybrid sampling technique to simultane-ously resolve tip-tilt and high-order aberrations,while the DSM performs real-time compensation through adaptive modal optimization.This unified architecture achieves symmetrical polarization suppression and high system throughput by min-imizing optical surfaces.A 600 mm ESAOT prototype incorporating a 12×12 micro-lens array HS f-WFS and 61-actuator piezoelectric DSM has been developed and successfully conducted on-sky photospheric observations.Validations in-cluding turbulence simulations,optical bench testing,and practical observations at the Lijiang observatory collectively confirm the system's capability to maintain aboutλ/10 wavefront error during active region tracking.This architectural breakthrough of the ESAOT addresses long-standing SAO integration challenges in solar astronomy and provides scala-bility analyses confirming direct applicability to the existing and future large solar observation facilities.
基金funding from the National Key Research and Development Program of China(2021YFF0502900)special fund for Research on the National Major Research Instruments of China(62027824)+2 种基金the National Natural Science Foundation of China(U24A20314)the Key Research and Development Program of Anhui Province in China(2022a05020028)the Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province.
文摘The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly applicable optical trapping system based on a custom-designed 2×3 optical tweezer array,which enables the real-time interception and manipulation of circulating leukocytes in live animals.By utilizing intrinsic velocity differences between leukocytes and red blood cells,the system achieves stable trapping of individual leukocytes in vessels 15-20μm in diameter and decelerates multiple cells in vessels greater than 20μm.Notably,it also enables the optical blockage of lymphatic vessels exceeding 50μm,a previously unreported capability.This label-free,noninvasive approach operates without repeated blood draws and is compatible with diverse vessel geometries and flow dynamics.The system offers a generalizable solution for in vivo cell extraction and analysis,paving the way for high-precision single-cell technologies in biomedical research and clinical translation.
基金supported by the Strategic Priority Research Program–Climate Change: Carbon Budget and Relevant Issues (Grant No. XDA05040300)National Natural Science Foundation of China (Grant No. 41175028)
文摘A differential optical absorption spectroscopy （DOAS）-like algorithm is developed to retrieve the column-averaged dry- air mole fraction of carbon dioxide from ground-based hyper-spectral measurements of the direct solar beam. Different to the spectral fitting method, which minimizes the difference between the observed and simulated spectra, the ratios of multiple channel-pairs--one weak and one strong absorption channel--are used to retrieve Xc02 from measurements of the shortwave infrared （SWIR） band. Based on sensitivity tests, a super channel-pair is carefully selected to reduce the effects of solar lines, water vapor, air temperature, pressure, instrument noise, and frequency shift on retrieval errors. The new algorithm reduces computational cost and the retrievals are le^s sensitive to temperature and H20 uncertainty than the spectral fitting method. Multi-day Total Carbon Column Observing Network （TCCON） measurements under clear-sky conditions at two sites （Tsukuba and Bremen） are used to derive Xc02 for the algorithm evaluation and validation. The DOAS-like results agree very well with those of the TCCON algorithm after correction of an airmass-dependent bias.
文摘The field of subwavelength optics has opened new avenues for investigating light–matter interactions by enabling the exploration of novel phenomena at the subwavelength scale. In recent decades,advancements in fundamental understanding and micro–nanotechnologies have significantly propelled the development of subwavelength optics and its practical applications.
基金supported by the National Natural Science Foundation of China(Grant Nos.62192774,62105243,61925504,6201101335,62020106009,62192770,62192772,62105244,62305250,and 62322217)the Science and Technology Commission of Shanghai Municipality(Grant Nos.17JC1400800,20JC1414600,and 21JC1406100)+1 种基金the Shanghai Municipal Science and Technology Major Project(Grant No.2021SHZDZX0100)the Fundamental Research Funds for the Central Universities.
文摘Manufacturing-robust imaging systems leveraging computational optics hold immense potential for easing manufacturing constraints and enabling the development of cost-effective,high-quality imaging solutions.However,conventional approaches,which typically rely on data-driven neural networks to correct optical aberrations caused by manufacturing errors,are constrained by the lack of effective tolerance analysis methods for quantitatively evaluating manufacturing error boundaries.This limitation is crucial for further relaxing manufacturing constraints and providing practical guidance for fabrication.We propose a physics-informed design paradigm for manufacturing-robust imaging systems with computational optics,integrating a physics-informed tolerance analysis methodology for evaluating manufacturing error boundaries and a physics-informed neural network for image reconstruction.With this approach,we achieve a manufacturing-robust imaging system based on an off-axis three-mirror freeform all-aluminum design,delivering a modulation transfer function exceeding 0.34 at the Nyquist frequency(72 lp/mm)in simulation.Notably,this system requires a manufacturing precision of only 0.5λin root mean square(RMS),representing a remarkable 25-fold relaxation compared with the conventional requirement of 0.02λin RMS.Experimental validation further confirmed that the manufacturing-robust imaging system maintains excellent performance in diverse indoor and outdoor environments.Our proposed method paves the way for achieving high-quality imaging without the necessity of high manufacturing precision,enabling practical solutions that are more cost-effective and time-efficient.
文摘I shall deserve the Reputation of having beene ye first to lay the grounds of two Sciences,"wrote Thomas Hobbes in 1646,"this of Optiques and yt other of natural Justice."For him,optics and politics were two prongs of the same effort:to naturalize humans’relations to their world and to each other.It was Descartes’Dioptrique,handed to him by Kenelm Digby in 1637,that cleared for him the path:naturalizing humans required physicalizing vision–as Kepler taught in his own optics–and removing from nature of all cognitive entities such as"species visible and intelligible."Between 1639 and 1646 Hobbes produced three professional,innovative treatises on optics founded upon"the opinion of the excellent Monsieur Des Cartes"but,finally,diverging from it in the most crucial point.For Descartes,ridding"Matter[of all]such Descriptions…as belong but to Spiritual Beings"required a spiritual,non-material entity to interpret the physical effects of the senses.Hobbes,however,insisted that the interpretation can and should be understood physically and mechanically,for"Vision is the judgement itself.
基金Supported by National Natural Science Foundation of China(No.82271107).
文摘AIM:To assess the variations in photoreceptor cell packing density(PCPD)across the retina among young healthy individuals with emmetropia,low and moderate myopia.METHODS:High-resolution adaptive optics scanning laser ophthalmoscopy(AOSLO)systems were utilized for retinal imaging with a large sampling window of 700μm×700μm.The study cohort included 14 emmetropic[spherical equivalent(SE)ranged+0.5 to-0.5 D],15 low myopic(SE ranged-0.5 to-3 D)and 21 moderate myopic(SE ranged-3 to-6 D)healthy young adults.Photoreceptors at 3°temporal,6°superior and inferior 6°were captured.Statistical analysis was then performed to obtain PCPD and cell spacing.RESULTS:The average age of participants was 22.54±2.86(ranged 20–30y)with no difference among 3 groups.At 3°temporal,the emmetropic group exhibited the highest PCPD of 15186.16±2050.54 cells/mm^(2),while the low and moderate myopic groups had PCPD of 14009.15±1073.01 and 13466.92±1121.71 cells/mm2,respectively.At 3°temporal,the emmetropic group also had the smallest cell spacing at 6.66±0.26 mm,compared to 6.85±0.26 and 6.91±0.28 mm for the low and moderate myopic groups,respectively.Compared to the emmetropic group,at 3°temporal,the myopic groups showed significantly reduced PCPD(low myopia:P=0.032;moderate myopia:P=0.001).At 6°inferior,the moderate myopic group exhibited a significant decrease in PCPD(P=0.013),while at 6°superior,there were no significant statistical differences in PCPD for the low and moderate myopic groups(P>0.05).In comparison to the emmetropic group,only the moderate myopic group showed significantly increased cell spacing at all three positions(temporal 3°:P=0.011,superior 6°:P=0.046,inferior 6°:P=0.013).Correlation analysis revealed a positive correlation between PCPD and axial length changes(P<0.05).CONCLUSION:Reduced PCPD and increased cell spacing strongly correlated with refractive error in mild to moderate myopic eyes,especially at 6°inferior to the fovea and the decreased PCPD in the macular region of myopic patients may be associated with increased axial lengthinduced retinal stretching.
基金supported by Yunnan Fundamental Research Projects(No.202101AT070003)the National Natural Science Foundation of China(No.42365007).
文摘Multi-axial differential optical absorption spectroscopy(MAX-DOAS)measurements were conducted in Xishuangbanna,Yunnan,China,between November 1,2021 and June 30,2022 to obtain vertical distributions of formaldehyde(HCHO)and glyoxal(CHOCHO).The observations show an increase in vertical column densities(VCDs)and volume mixing ratios(VMRs)for both HCHO and CHOCHO concentrations during periods of biomass combustion.The VCDs of HCHO and CHOCHO from TROPOMI are in good agreementwith the MAX-DOAS observations.(R^(2) HCHO=0.71;R^(2) CHOCHO=0.70).Regarding seasonal variations,HCHO predominantly occupies the upper layer(400-800 m)during the biomass burning,possibly attributed to the formation of secondary HCHO as the plume ascends during combustion.CHOCHO is primarily found in the lower layer(0-200 m),suggesting a longer lifespan for HCHO compared to CHOCHO,preventing the latter from diffusing to higher altitudes.Concerning the daily variation patterns,both HCHO and CHOCHO VMRs exhibited peaks at 9:00 and 13:00,which were attributed to the nighttime accumulation and midday oxidation.Furthermore,we also investigated the sources of volatile organic compounds(VOCs)using the CHOCHO to HCHO ratio(RGF).During the period of biomass burning,there are minimal differences in the daily RGF across layers,indicating that biomass burning is the predominant source.During the non-biomass burning period,the daily RGF shows significant differences among layers,indicating that emissions from biological and anthropogenic sources primarily contribute during the period.
基金supported by the National Key R&D Program of China(2023YFA1406200)the National Natural Science Foundation of China(T2521005,12174144,12474009,12174146,and 124B2059)the Special Construction Project Fund for Shan-dong Province Taishan Scholars.
文摘Multifunctional optical responsive materials have grown increasingly pivotal in addressingthe escalating demands of sensing,detection,and anti-counterfeiting applications[1,2].These materials exhibit distinct visible optical variations upon exposure to external stimuli,such as pressure,temperature,light,solvents,pH fluctuations,or mechanical force.Fluorescent sensing and anti-counterfeiting technologies leveraging these optical responses have emerged as highly promising solutions.
基金supported by the Innovation Pro-gram for Quantum Science and Technology(Grant Nos.2021ZD0300900 and 2021ZD0300902)the Strate-gic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB35010202)the Operation and Maintenance of Major Scientific and Technological In-frastructure of the Chinese Academy of Sciences(Grant No.2024000014).
文摘We report the SrII optical lattice clock at the National Time Service Center(NTSC).In this system,a blackbody radiation shield with movable lattice mitigates blackbody radiation shifts through active temperature control.A shallow optical lattice with minimal tunneling minimizes AC Stark shifts.Phase-locked counter-propagating lattice beams and conductive vacuum viewports further reduce systematic uncertainties and a novel initial-state preparation method simplifies the system.Clock transition spectra achieve a linewidth of 2.5 Hz with a 400 ms clock pulse,and self-comparison stability reaches 5.1×10^(-16)at 1 s.These advancements give this clock the potential to be a critical platform for realizing outstanding systematic uncertainties in the future.
