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Double beam near-infrared spectrometer for compensation of background water absorption and instrumental drift in intensity
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作者 CHANG Min PENG Dan XU Ke-xin 《Optoelectronics Letters》 EI 2007年第3期211-214,共4页
A double beam near-infrared spectrometer is developed to compensate the water absorption and instrumental drift in intensity. The spectrometer may be used for both single and double beam measurements,and the two opera... A double beam near-infrared spectrometer is developed to compensate the water absorption and instrumental drift in intensity. The spectrometer may be used for both single and double beam measurements,and the two operation modes are compared. The results show that the double beam technique eliminates instrumental drift in the single beam measurement and therefore the stability of the system increases by more than 20%. The compensation of the double beam system on water absorption is verified by the measurement of fat content in milk. The results show that the spectrum data based on double beam mode get better calibration model and lower prediction error than traditional single beam mode. 展开更多
关键词 双光束近红外光谱仪 光强 背景水吸光 仪器漂移 补偿
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Intelligent integration and advancement of multi-organ-on-a-chip
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作者 Chen-Xi Song Lu Huang 《Biomedical Engineering Communications》 2026年第1期1-3,共3页
Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technol... Multi-organ-on-a-chip(MOOC)technology represents a pivotal direction in the organ-on-a-chip field,seeking to emulate the complex interactions of multiple human organs in vitro through microfluidic systems.This technology overcomes the limitations of traditional single-organ models,providing a novel platform for investigating complex disease mechanisms and evaluating drug efficacy and toxicity.Although it demonstrates broad application prospects,its development still faces critical bottlenecks,including inadequate physiological coupling between organs,short functional maintenance durations,and limited real-time monitoring capabilities.Contemporary research is advancing along three key directions,including functional coupling,sensor integration,and full-process automation systems,to propel the technology toward enhanced levels of physiological relevance and predictive accuracy. 展开更多
关键词 investigating complex disease mechanisms emulate complex interactions multiple human organs vitro sensor integration intelligent integration predictive accuracy physiological coupling multi organ chip microfluidic systemsthis
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Specific dendritic spine modifications and dendritic transport:From in vitro to in vivo
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作者 Albert H.K.Fok Charlotte H.M.Lam Cora S.W.Lai 《Neural Regeneration Research》 2026年第2期665-666,共2页
Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for sign... Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for signal transduction.The plasticity of spine morphologies provides a tunable handle to regulate calcium signal dynamics,allowing rapid regulation of protein expression necessary to establish and maintain synapses(Cornejo et al.,2022).If excitatory inputs were to be located primarily on dendritic shafts,dendrites would frequently short-circuit,preventing voltage signals from propagating(Cornejo et al.,2022).It is thus not surprising that the structural plasticity of dendritic spines is closely linked to synaptic plasticity and memory formation(Berry and Nedivi,2017).While comprehensive in vitro studies have been conducted,in vivo studies that directly tackle the mechanism of dendritic transport and translation in regulating spine plasticity spatiotemporally are limited. 展开更多
关键词 excitatory synapses principal neuronsplaying compartmentalized environment establish maintain synapses cornejo dendritic spines regulate calcium signal dynamicsallowing regulation protein expression dendritic shaft
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Intelligent Photonics:A Disruptive Technology to Shape the Present and Redefine the Future 被引量:6
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作者 Danlin Xu Yuchen Ma +1 位作者 Guofan Jin Liangcai Cao 《Engineering》 2025年第3期186-213,共28页
Artificial intelligence(AI)has taken breathtaking leaps forward in recent years,evolving into a strategic technology for pioneering the future.The growing demand for computing power—especially in demanding inference ... Artificial intelligence(AI)has taken breathtaking leaps forward in recent years,evolving into a strategic technology for pioneering the future.The growing demand for computing power—especially in demanding inference tasks,exemplified by generative AI models such as ChatGPT—poses challenges for conventional electronic computing systems.Advances in photonics technology have ignited interest in investigating photonic computing as a promising AI computing modality.Through the profound fusion of AI and photonics technologies,intelligent photonics is developing as an emerging interdisciplinary field with significant potential to revolutionize practical applications.Deep learning,as a subset of AI,presents efficient avenues for optimizing photonic design,developing intelligent optical systems,and performing optical data processing and analysis.Employing AI in photonics can empower applications such as smartphone cameras,biomedical microscopy,and virtual and augmented reality displays.Conversely,leveraging photonics-based devices and systems for the physical implementation of neural networks enables high speed and low energy consumption.Applying photonics technology in AI computing is expected to have a transformative impact on diverse fields,including optical communications,automatic driving,and astronomical observation.Here,recent advances in intelligent photonics are presented from the perspective of the synergy between deep learning and metaphotonics,holography,and quantum photonics.This review also spotlights relevant applications and offers insights into challenges and prospects. 展开更多
关键词 Artificial intelligence Optical neural network Deep learning Metaphotonics HOLOGRAPHY Quantum photonics
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Advancements in chromium-tolerant air electrode for solid oxide cells:A mini-review 被引量:1
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作者 HUANG Jiongyuan CHEN Zhiyi +3 位作者 LUO Yujie AI Na JIANG Sanping CHEN Kongfa 《燃料化学学报(中英文)》 北大核心 2025年第2期249-261,共13页
Solid oxide cells(SOCs)are emerging devices for efficient energy storage and conversion.However,during SOC operation,gaseous chromium(Cr)species released from Fe-Cr alloy interconnect can lead to Cr deposition and poi... Solid oxide cells(SOCs)are emerging devices for efficient energy storage and conversion.However,during SOC operation,gaseous chromium(Cr)species released from Fe-Cr alloy interconnect can lead to Cr deposition and poisoning of air electrodes,causing substantial degradation in electrochemical performance and compromising the longterm stability of SOCs.This mini-review examines the mechanism of Cr deposition and poisoning in air electrodes under both fuel-cell and electrolysis modes.Furthermore,emphasis is placed on the recent advancements in strategies to mitigate Cr poisoning,offering insights into the rational design and development of active and Cr-tolerant air electrodes for SOCs. 展开更多
关键词 solid oxide cells air electrodes Cr poisoning surface modification
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Improvement on Qm in high-power piezoelectric ceramics through[111]c texture engineering 被引量:1
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作者 Wenming Shi Hongjun Zhang +4 位作者 Yingchun Liu Lang Bian Wenjing Bi Yuanhao Deng Bin Yang 《Journal of Materials Science & Technology》 2025年第13期260-268,共9页
Improving mechanical quality factor Qm is of great significance for high-power applications.Here,a new strategy of the[111]c texture engineering was proposed to enhance the performances of high-power piezoelectric cer... Improving mechanical quality factor Qm is of great significance for high-power applications.Here,a new strategy of the[111]c texture engineering was proposed to enhance the performances of high-power piezoelectric ceramics.The 5 vol%BaTiO_(3)(BT)templates with the[111]c preferred orientation were in-troduced into matrix powders of 0.03 Pb(Mn_(1/3) Nb_(2/3))O_(3)-0.33Pb(Ni_(1/3) Nb_(2/3))O_(3)-0.28 PbZrO_(3)-0.36PbTiO_(3)(28PZ(R))to form the[111]c textured ceramics(28PZ(T)),possessing a texture degree of 74%.The mul-tiple of uniform density in EBSD increased from 0.63 in randomly oriented 28 PZ(R)to 6.63 in 28PZ(T).The good lattice matching between BT templates and textured grains was observed using high-resolution transmission electron microscopy,confirming the microscopic origin of the[111]c texture.The maximum phase angleθmax of 88.2°was quite near 90°in 28PZ(T),ensuring the optimal Qm value of 1275 and the great figure of merit of 255,000 pC/N.The increased Qm in[111]c texture ceramics was confirmed due to the reduced intrinsic polarization directions rather than the pinning effect of the internal bias field.Larger grain sizes with larger domains restrained the movement of domain walls in 28 PZ(T),which was also favorable to higher Qm.This work may provide a new promising route for further high-power applications. 展开更多
关键词 _(c)texture Texture process High Q_(m) High power CRYSTALLOGRAPHY
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Machine learning-assisted microfluidic approach for broad-spectrum liposome size control 被引量:1
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作者 Yujie Jia Xiao Liang +6 位作者 Li Zhang Jun Zhang Hajra Zafar Shan Huang Yi Shi Jian Chen Qi Shen 《Journal of Pharmaceutical Analysis》 2025年第6期1238-1248,共11页
Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been wide... Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been widely employed for liposome preparation.Although some studies have explored factors affecting liposomal size in microfluidic processes,most focus on small-sized liposomes,predominantly through experimental data analysis.However,the production of larger liposomes,which are equally significant,remains underexplored.In this work,we thoroughly investigate multiple variables influencing liposome size during microfluidic preparation and develop a machine learning(ML)model capable of accurately predicting liposomal size.Experimental validation was conducted using a staggered herringbone micromixer(SHM)chip.Our findings reveal that most investigated variables significantly influence liposomal size,often interrelating in complex ways.We evaluated the predictive performance of several widely-used ML algorithms,including ensemble methods,through cross-validation(CV)for both lipo-some size and polydispersity index(PDI).A standalone dataset was experimentally validated to assess the accuracy of the ML predictions,with results indicating that ensemble algorithms provided the most reliable predictions.Specifically,gradient boosting was selected for size prediction,while random forest was employed for PDI prediction.We successfully produced uniform large(600 nm)and small(100 nm)liposomes using the optimised experimental conditions derived from the ML models.In conclusion,this study presents a robust methodology that enables precise control over liposome size distribution,of-fering valuable insights for medicinal research applications. 展开更多
关键词 Liposomes MICROFLUIDICS Liposomal size SHM Machine learning
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Frequency optimization for electrodes in implantable brain-computer interfaces 被引量:1
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作者 CHEN Han LIU Xiangyu +2 位作者 CHENG Jiajun QIN Jiangfan ZHANG Xueli 《Journal of Southeast University(English Edition)》 2025年第3期366-374,共9页
Fully implanted brain-computer interfaces(BCIs)are preferred as they eliminate signal degradation caused by interference and absorption in external tissues,a common issue in non-fully implanted systems.To optimize the... Fully implanted brain-computer interfaces(BCIs)are preferred as they eliminate signal degradation caused by interference and absorption in external tissues,a common issue in non-fully implanted systems.To optimize the design of electroencephalography electrodes in fully implanted BCI systems,this study investigates the penetration and absorption characteristics of microwave signals in human brain tissue at different frequencies.Electromagnetic simulations are used to analyze the power density distribution and specific absorption rate(SAR)of signals at various frequen-cies.The results indicate that lower-frequency signals offer advantages in terms of power density and attenuation coeffi-cients.However,SAR-normalized analysis,which considers both power density and electromagnetic radiation hazards,shows that higher-frequency signals perform better at superficial to intermediate depths.Specifically,at a depth of 2 mm beneath the cortex,the power density of a 6.5 GHz signal is 247.83%higher than that of a 0.4 GHz signal.At a depth of 5 mm,the power density of a 3.5 GHz signal exceeds that of a 0.4 GHz signal by 224.16%.The findings suggest that 6.5 GHz is optimal for electrodes at a depth of 2 mm,3.5 GHz for 5 mm,2.45 GHz for depths of 15-20 mm,and 1.8 GHz for 25 mm. 展开更多
关键词 brain-computer interfaces electromagnetic simulation electroencephalography electrodes power den-sity specific absorption rate
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The Collaborative Development of Sensors and Artificial Intelligence 被引量:1
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作者 Shangchun Fan Feiyang Zhang Yufu Qu 《Instrumentation》 2025年第1期1-10,共10页
Sensors are the source of information technology and the first unit of intelligent systems,providing real-world"data"for artificial intelligence.They play a crucial role in various aspects of the national ec... Sensors are the source of information technology and the first unit of intelligent systems,providing real-world"data"for artificial intelligence.They play a crucial role in various aspects of the national economy and the people's livelihood,such as national defense security and the development of new quality productive forces.This paper provides a comprehensive survey of how sensors should adapt to the current upsurge of artificial intelligence,analyzing their technical connotations,application characteristics,and inherent limitations.Furthermore,with a sensor-oriented mindset,it is proposed that sensors will dominate information technology,upgrade connotations,advance ubiquitous bionic intelligence and engage in a"symbiotic dance"with artificial intelligence.This overview provides a promising direction for the higher-level development of sensors and artificial intelligence. 展开更多
关键词 SENSOR artificial intelligence information technology new quality productive forces collaborative development
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Formation mechanism of W phase and its effects on the mechanical properties of Mg-Dy-Zn alloys 被引量:1
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作者 J.S.Chen C.J.Ji +4 位作者 Q.Y.Huang Y.Z.Zeng H.B.Xie P.Chen B.Z.Sun 《Journal of Magnesium and Alloys》 2025年第5期2174-2189,共16页
The morphology and dimension of W phases play an important role in determining mechanical properties of Mg-RE-Zn(where RE denotes rare earth elements)alloys.In this study,theγ′platelet and W particle occurred in the... The morphology and dimension of W phases play an important role in determining mechanical properties of Mg-RE-Zn(where RE denotes rare earth elements)alloys.In this study,theγ′platelet and W particle occurred in the aged Mg-2Dy-0.5Zn(at.%)alloys were investigated by aberration-corrected scanning transmission electron microscopy.A novel formation mechanism of W phase was proposed,and its effects on the morphology and dimension of W particle,as well as mechanical properties of Mg-2Dy-0.5Zn alloys,were also discussed particularly.Different from other Mg-RE-Zn alloys,the nucleation and growth of W particle in Mg-Dy-Zn alloys mainly depend on the precipitatedγ′platelet.Primarily,a mass of Dy and Zn solute atoms concentrated nearγ′platelet or between two adjacentγ′platelets can meet the composition requirement of W particle nucleation.Next,the smaller interfacial mismatch between W andγ′facilitates the nucleation and growth of W particle.Thirdly,the growth of W particle can be achieved by consuming the surroundingγ′platelets.The nucleation and growth mechanisms make W particles exhibit rectangular or leaf-like and remain at the nanoscale.The coexistence ofγ′platelets and nanoscale W particles,and some better interfacial relationships between phases,lead to a high strength-ductility synergy of alloy.The findings may provide some fundamental guidelines for the microstructure design and optimization of new-type Mg-based alloys. 展开更多
关键词 Magnesium alloys Scanning transmission electron microscopy W particle Formation mechanism Mechanical properties
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Fast-zoom and high-resolution sparse compound-eye camera based on dual-end collaborative optimization 被引量:1
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作者 Yi Zheng Hao-Ran Zhang +5 位作者 Xiao-Wei Li You-Ran Zhao Zhao-Song Li Ye-Hao Hou Chao Liu Qiong-Hua Wang 《Opto-Electronic Advances》 2025年第6期4-15,共12页
Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution... Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution sparse compound-eye camera(CEC)based on dual-end collaborative optimization is proposed,which provides a cost-effective way to break through the trade-off among the field of view,resolution,and imaging speed.In the optical end,a sparse CEC based on liquid lenses is designed,which can realize large-field-of-view imaging in real time,and fast zooming within 5 ms.In the computational end,a disturbed degradation model driven super-resolution network(DDMDSR-Net)is proposed to deal with complex image degradation issues in actual imaging situations,achieving high-robustness and high-fidelity resolution enhancement.Based on the proposed dual-end collaborative optimization framework,the angular resolution of the CEC can be enhanced from 71.6"to 26.0",which provides a solution to realize high-resolution imaging for array camera dispensing with high optical hardware complexity and data transmission bandwidth.Experiments verify the advantages of the CEC based on dual-end collaborative optimization in high-fidelity reconstruction of real scene images,kilometer-level long-distance detection,and dynamic imaging and precise recognition of targets of interest. 展开更多
关键词 compound-eye camera ZOOM high resolution collaborative optimization
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Carbon-based quantum dots/nanodots materials for potassium ion storage 被引量:1
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作者 Zhanheng Yan Weiqing Su +6 位作者 Weiwei Xu Qianhui Mao Lisha Xue Huanxin Li Wuhua Liu Xiu Li Qiuhui Zhang 《Chinese Chemical Letters》 2025年第4期83-95,共13页
With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ... With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ion battery is promising to replace the lithium-ion battery in the field of large-scale energy storage by virtue of its low price and environmental friendliness.At present,the research on the anode materials of potassium ion batteries mainly focuses on carbon materials and the design of various nanostructured metal-based materials.Problems such as poor rate performance and inferior cycle life caused by electrode structure comminution during charge and discharge have not been solved.Quantum dots/nanodots materials are a new type of nanomaterials that can effectively improve the utilization of electrode materials and reduce production costs.In addition,quantum dots/nanodots materials can enhance the electrode reaction kinetics,reduce the stress generated in cycling,and effectively alleviate the agglomeration and crushing of electrode materials.In this review,we will systematically introduce the synthesis methods,K+storage properties and K+storage mechanisms of carbon quantum dots and carbon-based transition metal compound quantum dots composites.This review will have significant references for potassium ion battery researchers. 展开更多
关键词 Quantum dots NANODOTS Potassium ion battery ANODE Composite material
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WSi_(2)的W-L_(3)边高分辨共振非弹性X射线散射研究
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作者 赵喆芊 汪书兴 +4 位作者 王希源 苏洋 马子茹 黄新朝 朱林繁 《物理学报》 北大核心 2025年第18期124-131,共8页
随着X射线光源的进步和量子光学的发展,形成了X射线量子光学这一前沿分支学科.原子内壳层跃迁是重要的X射线量子光学体系,它具有跃迁种类丰富和表征手段多样、覆盖波段范围宽等优势.但内壳层空穴的自然线宽较宽且受局域电子结构影响,使... 随着X射线光源的进步和量子光学的发展,形成了X射线量子光学这一前沿分支学科.原子内壳层跃迁是重要的X射线量子光学体系,它具有跃迁种类丰富和表征手段多样、覆盖波段范围宽等优势.但内壳层空穴的自然线宽较宽且受局域电子结构影响,使得实验上缺乏纯粹的二能级跃迁,成了制约X射线量子光学发展的瓶颈之一.本文利用共振非弹性X射线散射技术,在实验上分离了WSi_(2)中W-L_(3)边的白线,从而为基于原子内壳层跃迁的X射线量子光学体系提供了二能级方案,也为这一领域的发展提供了强有力的实验技术支持. 展开更多
关键词 X射线量子光学 内壳层跃迁 共振非弹性X射线散射 二能级
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“光纤传感技术及应用”专题前言
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作者 董永康 郭团 +1 位作者 孙琪真 龚元 《红外与激光工程》 北大核心 2025年第4期I0001-I0002,共2页
自20世纪激光和光纤技术问世以来,相关行业的发展带动了工业技术的巨大变革,伴生了光纤传感技术的巨大研究潜质和应用前景。以光波为载体,以光纤为媒质,光纤传感技术在兼具抗电磁干扰、耐腐蚀、高灵敏度、轻质量和小体积等优势的前提下... 自20世纪激光和光纤技术问世以来,相关行业的发展带动了工业技术的巨大变革,伴生了光纤传感技术的巨大研究潜质和应用前景。以光波为载体,以光纤为媒质,光纤传感技术在兼具抗电磁干扰、耐腐蚀、高灵敏度、轻质量和小体积等优势的前提下,不断发展并实现了涵盖温度、应变、压力、气体、物质识别、运动、声波、位移、磁场、液位等参量的高性能感知在电力、石油、化工、建筑、交通、医疗、安防及环保等领域卓有成效。 展开更多
关键词 气体 激光 高灵敏度 压力 工业技术
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Relationship Between Stress and Texture in L1_(0)-FePt Thin Films
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作者 Wang Xuanli Li Wei 《稀有金属材料与工程》 北大核心 2025年第2期337-342,共6页
Impact of texture type on the magnetic properties of ultrahigh density perpendicular magnetic recording media L1_(0)-FePt thin film was investigated,so were the texture formation and evolution mechanism.Reuss,Voigt,an... Impact of texture type on the magnetic properties of ultrahigh density perpendicular magnetic recording media L1_(0)-FePt thin film was investigated,so were the texture formation and evolution mechanism.Reuss,Voigt,and Hill models were used to determine the anisotropic elastic modulus of L1_(0)-FePt thin film with fiber texture.Then,the elastic strain energies of thin films under various stress conditions were calculated.Results reveal that the stress condition has a significant influence on the fiber texture evolution.When the L1_(0)-FePt thin film is subjected to compressive in-plane strain prior to ordering phase transformation,the formation of{100}fiber texture is promoted.On the contrary,the ordering phase transformation under tensile in-plane strain promotes the{001}fiber texture formation. 展开更多
关键词 L1_(0)-FePt film TEXTURE STRESS elastic modulus
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Spin-dependent amplitude and phase modulation with multifold interferences via single-layer diatomic all-silicon metasurfaces 被引量:2
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作者 Hui Li Chenhui Zhao +6 位作者 Jie Li Hang Xu Wenhui Xu Qi Tan Chunyu Song Yun Shen Jianquan Yao 《Opto-Electronic Science》 2025年第3期2-15,共14页
Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarizat... Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarization.Geometric phase profiles with spin-selective properties are commonly associated with wavefront modulation,allowing the implementation of conjugate strategies within orthogonal circularly polarized channels.Simultaneous control of these characteristics in a single-layered diatomic metasurface will be an apparent technological extension.Here,spin-selective modulation of terahertz(THz)beams is realized by assembling a pair of meta-atoms with birefringent effects.The distinct modulation functions arise from geometric phase profiles characterized by multiple rotational properties,which introduce independent parametric factors that elucidate their physical significance.By arranging the key parameters,the proposed design strategy can be employed to realize independent amplitude and phase manipulation.A series of THz metasurface samples with specific modulation functions are characterized,experimentally demonstrating the accuracy of on-demand manipulation.This research paves the way for all-silicon meta-optics that may have great potential in imaging,sensing and detection. 展开更多
关键词 diatomic metasurface geometric phase complex amplitude modulation spin-selective
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Color projector light intensity adaptive high dynamic range 3D measurement method
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作者 HUANG Hao-zhen NIU Bin +2 位作者 CHENG Shen QU Xing-hua ZHANG Fu-min 《中国光学(中英文)》 北大核心 2025年第5期1219-1229,共11页
The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,re... The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,resulting in point cloud loss or reduced accuracy.To address this issue,unlike the pixel modulation method of projectors,we utilize the characteristics of color projectors where the intensity of the three-channel LED can be controlled independently.We propose a method for separating the projector's three-channel light intensity,combined with a color camera,to achieve single exposure and multi-intensity image acquisition.Further,the crosstalk coefficient is applied to predict the three-channel reflectance of the measured object.By integrating clustering and channel mapping,we establish a pixel-level mapping model between the projector's three-channel current and the camera's three-channel image intensity,which realizes the optimal projection current prediction and the high dynamic range(HDR)image acquisition.The proposed method allows for high-precision three-dimensional(3D)data acquisition of HDR scenes with a single exposure.The effectiveness of this method has been validated through experiments with standard planes and standard steps,showing a significant reduction in mean absolute error(44.6%)compared to existing singleexposure HDR methods.Additionally,the number of images required for acquisition is significantly reduced(by 70.8%)compared to multi-exposure fusion methods.This proposed method has great potential in various FPP-related fields. 展开更多
关键词 fringe projection profilometry crosstalk coefficient optimal projection currents high dynamic range
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Structural design of a wide-ridge mid-wave infrared quantum cascade laser based on a supersymmetric waveguide
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作者 DU Shu-Hao ZHENG Xian-Tong +7 位作者 JIA Han CUI Jin-Tao ZHANG Shi-Ya LIU Yuan FENG Yu-Lin ZHANG Chun-Qian LIU Ming ZHANG Dong-Liang 《红外与毫米波学报》 北大核心 2025年第3期452-458,共7页
In the process of power scaling large-area Quantum Cascade Lasers(QCLs),challenges such as degradation of beam quality and emission of multilobed far-field modes are frequently encountered.These issues become particul... In the process of power scaling large-area Quantum Cascade Lasers(QCLs),challenges such as degradation of beam quality and emission of multilobed far-field modes are frequently encountered.These issues become particularly pronounced with an increase in ridge width,resulting in multimode problems.To tackle this,an innovative multi ridge waveguide structure based on the principle of supersymmetry(SUSY)was proposed.This structure comprises a wider main waveguide in the center and two narrower auxiliary waveguides on either side.The high-order modes of the main waveguide are coupled with the modes of the auxiliary waveguides through mode-matching design,and the optical loss of the auxiliary waveguides suppresses these modes,thereby achieving fundamental mode lasing of the wider main waveguide.This paper employs the finite difference eigenmode(FDE)method to perform detailed structural modeling and simulation optimization of the 4.6μm wavelength quantum cascade laser,successfully achieving a single transverse mode QCL with a ridge width of 10μm.In comparison to the traditional single-mode QCL(with a ridge width of about 5μm),the MRW structure has the potential to increase the gain area of the laser by 100%.This offers a novel design concept and methodology for enhancing the single-mode luminous power of mid-infrared quantum cascade lasers,which is of considerable significance. 展开更多
关键词 quantum cascade laser mode competition SUPERSYMMETRY MID-INFRARED auxiliary waveguides
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Glass catfish inspired subaquatic abrasion-resistant anti-fouling window fabricated by femtosecond laser electrodeposition 被引量:1
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作者 Jialiang Zhang Fangzheng Ren +6 位作者 Qing Yang Qingyun Ma Jie Liang Yizhao Meng Xiaodan Gou Chongxiao Xia Feng Chen 《International Journal of Extreme Manufacturing》 2025年第1期383-393,共11页
Transparent materials utilized as underwater optical windows are highly vulnerable to various forms of pollution or abrasion due to their intrinsic hydrophilic properties.This susceptibility is particularly pronounced... Transparent materials utilized as underwater optical windows are highly vulnerable to various forms of pollution or abrasion due to their intrinsic hydrophilic properties.This susceptibility is particularly pronounced in underwater environments where pollutants can impede the operation of these optical devices,significantly degrading or even compromising their optical properties.The glass catfish,known for its remarkable transparency in water,maintains surface cleanliness and clarity despite exposure to contaminants,impurities abrasion,and hydraulic pressure.Inspired by the glass catfish’s natural attributes,this study introduces a new solution named subaquatic abrasion-resistant and anti-fouling window(SAAW).Utilizing femtosecond laser ablation and electrodeposition,the SAAW is engineered by embedding fine metal bone structures into a transparent substrate and anti-fouling sliding layer,akin to the sturdy bones among catfish’s body.This approach significantly bolsters the window’s abrasion resistance and anti-fouling performance while maintaining high light transmittance.The sliding layer on the SAAW’s surface remarkably reduces the friction of various liquids,which is the reason that SAAW owns the great anti-fouling property.The SAAW demonstrates outstanding optical clarity even after enduring hundreds of sandpaper abrasions,attributing to the fine metal bone structures bearing all external forces and protecting the sliding layer of SAAW.Furthermore,it exhibits exceptional resistance to biological adhesion and underwater pressure.In a green algae environment,the window remains clean with minimal change in transmittance over one month.Moreover,it retains its wettability and anti-fouling properties when subjected to a depth of 30 m of underwater pressure for 30 d.Hence,the SAAW prepared by femtosecond laser ablation and electrodeposition presents a promising strategy for developing stable optical windows in liquid environments. 展开更多
关键词 ANTI-FOULING femtosecond laser subaquatic window slippery surface abrasion resistance
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Fabrication of SnS_(2)/C_(3)N_(5), heterojunction photocatalyst for highly efficient hydrogen production and organic pollutant degradation
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作者 GAO Yanan SHI Ming +2 位作者 YANG Jingxuan WANG Yajie LIU Bin 《燃料化学学报(中英文)》 北大核心 2025年第3期336-347,共12页
The semiconductor photocatalysis are considered as one of the most promising candidates in hydrogen energy source and environmental remediation area.In this paper,flower-shaped SnS,is successfully combined on g-C,Ns,a... The semiconductor photocatalysis are considered as one of the most promising candidates in hydrogen energy source and environmental remediation area.In this paper,flower-shaped SnS,is successfully combined on g-C,Ns,and the well matching band structure successfully constitutes a new Type-II heterojunction.As expected,the photocatalytic hydrogen production experiment showed that the quantity of hydrogen produced on 5% SnS_(2)/C_(3)N_(5)was 922.5μmol/(g.h),which is 3.6 times higher than that of pure g-C_(3)N_(5).Meanwhile,in photocatalytic degradation of methylene blue,5%SnS2/C,Ns composite material can degrade 95% of contaminants within 40 min,showing good photocatalytic degradation performance.The mechanism study indicates that SnS_(2)/C_(3)N_(5)heterojunction improves the photogenerated charge migration rate and reduces the electron-hole recombination rate,and effectively improves the photocatalytic performance of g-C_(3)N_(5).This work provides a new idea for designing C,Ns-based heterojunctions with efficient hydrogen production and degradation performance. 展开更多
关键词 C_(3)N_(5) stannic disulfide photocatalysis hydrogen PHOTODEGRADATION
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