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Materials Removal Mechanism of Single Crystalline Sic with Laser-Induced Periodic Surface Structures (LIPSS)

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SSRN 2023年

作者： Chen, Pei Chi, Zhuangzhuang Pan, Rui Qin, Fei Qiu, Pei Huang, Jiaxu Xu, Shaolin Institute of Electronics Packaging Technology & Reliability Faculty of Materials and Manufacturing Beijing University of Technology Beijing100124 China Beijing Key Laboratory of Advanced Manufacturing Technology Faculty of Materials and Manufacturing Beijing University of Technology Beijing100124 China Institute of Intelligent Forming Equipment and System Faculty of Materials and Manufacturing Beijing University of Technology Beijing100124 China Department of Mechanical and Energy Engineering Southern University of Science and Technology Shenzhen518055 China

The surface modification by ultra-fast laser could regulate the mechanical properties of hard and brittle materials. Since silicon carbide (SiC) is too hard to be machined with acceptable removal rate and quality by mechanical abrasives, and femtosecond laser (fs-laser) assisted grinding could be a potential method to improve the machinability of SiC. Under fs-laser modulating, SiC surface could be modified to generate laser-induced periodic surface structures (LIPSS). Understanding the mechanical properties and material removal mechanism of the LIPPS surface is crucial to accomplish a high efficiency and quality machining process. This paper aims to investigate the effects of fs-laser modification on the mechanical properties, removal mechanism, removal efficiency, and microstructure changes of 4H-SiC surface during removal, together with those of the original 4H-SiC surface for comparison. The hardness and elastic recovery ability of the modified layer are determined by nano-indentation test, and the nano-scratch test is adopted to study the materials removal behavior. The removal efficiency and the quality of the modified surface is significantly improved. Phase transformation is observed in the scratching area, which reveals the existence of ductile mode removal. Moreover, the stress distribution and the change of scratching force on the surface of SiC before and after modification are studied by finite element method (FEM). The results show that the stress distribution and transmission when scratched on the modified surface is lower than that of the original surface, and the scratching force under the same scratch conditions is greatly reduced. Therefore, the fs-laser modification of SiC could be an effect method to improve the grinding efficiency and quality in mass production of industry. © 2023, The Authors. All rights reserved.

关键词： Silicon carbide

Non-contact Physiological Parameters Detection Based on MTCNN and EVM 5th

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Non-contact Physiological Parameters Detection Based on MTCN...

5th International Conference on Cognitive systems and Signal Processing, ICCSIP 2020

作者： Zhao, Jinfa Zhang, Wenchang Chai, Rongxuan Wu, Hang Chen, Wei Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Tianjin University of Technology Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin China Institute of Medical Support Technology Academy of Military Sciences of Chinese PLA Tianjin China

ISBN: (纸本)9789811623356

Non-contact physiological parameters detection has become an important but challenging task. This paper proposes a novel framework for Non-contact physiological parameters detection, which is based on MTCNN (Multi-task convolutional neural network) and EVM (Eulerian Video Magnification). The MTCNN is applied to compensate negative effects of the pseudo motion for improving the efficiency of face detection. The Laplacian pyramid of EVM is added to our framework to perform motion amplification to achieve simultaneous extraction of heart rate and respiration rate, which improves the accuracy of non-contact physiological parameter detection. Then we use FFT to analyze the relevant frequency bands in time domain and calculate the heart rate and breathing rate. In order to improve efficiency, GPU acceleration is implemented under the TensorRT framework. The experimental results based on data sets DUSS (detection under slight shaking) and DUO (detection under occlusion) show the effectiveness of this method. The average error of the heart rate and respiration rate are −0.1 and 0.6, respectively. Our method achieves comparable performance to finger clip oximeter with a good consistency, even in the case of wearing a mask. © 2021, Springer Nature Singapore Pte Ltd.

关键词： Efficiency

A Novel Magnetoelastic Biosensor Based on Pdms/Fesib/Qds Composite Film for African Swine Fever Virus Detections

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SSRN 2024年

作者： Liu, Yuanhang Sang, Shengbo Zhao, Dong Ge, Yang Xue, Juanjuan Duan, Qianqian Guo, Xing Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System of The Ministry of Education Taiyuan University of Technology Taiyuan030024 China Shanxi Research Institute of 6D Artificial Intelligence Biomedical Science Taiyuan030024 China

African swine fever (ASF) is a highly contagious and severe hemorrhagic disease caused by the African swine fever virus (ASFV). The continuous spread of ASFV affects the safety of global meat supply, so the establishment of sensitive and specific detection methods for ASFV has become an important hot spot in food safety. Herein, we developed a flexible magnetoelastic (ME) biosensor based on PDMS/FeSiB/QDs composite films for the detection of ASFV. Based on the high luminescence performance of CsPbBr3 quantum dots and the excellent magnetoelastic effect of FeSiB, flexible ME biosensors convert stress signals generated by antibody-antigen-specific binding into optical and electromagnetic signals. The nanostructures covalently linked by quantum dots and PDMS provide biomodification sites for ASFV antibodies, simplifying the functionalization modification process compared to conventional biosensors. The deformation of the PDMS film is amplified and conversion of surface stress signal to electrical signal is enhanced by exposing the biosensor to a uniform magnetic field. The experimental results proved that the flexible ME biosensor has wide linear range of 10 ng/mL - 100 μg/mL, and the detection limit is as low as 0.7933 ng/mL. Moreover, the flexible ME biosensor have also shown to good stability, sensitivity and specificity. © 2024, The Authors. All rights reserved.

关键词： Biosensors

Small-Size Zif-8/In2o3 Core-Shell Nanocomposites for Highly Specific Detection of Ppb-Level No2

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SSRN 2024年

作者： Wang, Hongtao Zhang, Yaodan Xie, Yuanchao Han, Dan Ma, Jianan Sang, Shengbo Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System the Ministry of Education Taiyuan University of Technology Taiyuan030024 China Shanxi Research Institute of 6D Artificiat Intelligence Biomedical Science Taiyuan030024 China

The enhanced sensitivity and selectivity of nitrogen dioxide (NO2) gas sensors are paramount for atmospheric environmental monitoring. In this work, a novel small-size ZIF-8/In2O3 core-shell nanocubes gas sensor was fabricated using a straightforward solvothermal method, complemented by in situ modification. The ZIF-8 film markedly increased the specific surface area of In2O3 nanocubes from 60.64 m²/g to 140.84 m²/g. Concurrently, there was a rise in the content of adsorbed oxygen ions on the surface. The gas-sensing results demonstrated that the ZIF-8/In2O3 composites achieved a response of 56.3 to 1 ppm of NO2, with an exceptionally low detection limit of 1 ppb. Importantly, it exhibited unique selectivity for NO2 over other interfering gases. The outstanding NO2 gas-sensing performance of the ZIF-8/In2O3 composites can be attributed to the grain model effect inherent in the In2O3 (with side lengths of approximately 40-50 nm), along with the sensitization influence and filtering efficacy of ZIF-8. This advancement in gas sensor technology has significant potential for applications in the rapid detection of low-concentration NO2 gas. © 2024, The Authors. All rights reserved.

关键词： Indium compounds

Polarization-Induced Proton Adsorption and Charge Separation in Pyrene-Based Conjugated Microporous Polymers Via Substituent Regulation for Efficient Photocatalytic Hydrogen Evolution

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SSRN 2023年

作者： Ren, Runtang Jiao, Zhengxu Li, Zhanfeng Tian, Yue Liu, Baoyou Yue, Gang Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan030024 China Institute of Carbon Materials College of Materials Science and Engineering Taiyuan University of Technology Taiyuan030024 China Technology Innovation Center Ningxia Sinostar Display Material Co. Ltd. Yinchuan750003 China

Constructing photocatalysts with efficient light-harvesting abilities and charge separation properties is highly promising but still challenging for boosting photocatalytic hydrogen evolution from water. Herein, we report a simple and general polarization strategy through substituent regulation such as fluorination, chlorination and cyanation, to promote the photon capture and charge separation and unveil the latent structure–property–activity relationship in pyrene-based conjugated microporous polymers (CMPs). Notably, the introduction of fluorine, chlorine and cyano substituents onto the well-known full donor pyrene-benzene-based CMP network (Py-B) could induce a strong dipole along C–F/–Cl/–CN bonds and the backbone local polarization enhancement due to their strong electron-withdrawing ability, which afforded CMPs have a variety of superior effects such as narrowing band gaps, expanding optical absorption, improving interfacial wettability and solid-state morphology, and promoting charge separation inside organic photocatalysts. As a result, 1.73/2.50/4.69-fold increases of the hydrogen evolution rates of the –F/–Cl/–CN modified CMPs under visible light (λ > 420 nm) irradiation without Pt co-catalysts can be obtained in comparison with the counterpart Py-B (28.5/41.3/77.4 mmol g−1 h−1 vs 16.5 mmol g−1 h−1). Impressively, we find that the photocatalytic performance of this series of photocatalysts is linearly related to the dipole moment of polymers. Our studies reveal that the backbone local polarization enhancement induced by the substituent regulation could achieve high-performance organic photocatalysts toward solar-to-chemical energy conversion. © 2023, The Authors. All rights reserved.

关键词： Polarization

Ultrafast polarization modulation with high-purity chiral quasi-BIC metasurfaces

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Chinese Optics Letters 2025年第5期 142-148页

作者：赖方兴范宇斌沙新博邓画春蒋雄肖淑敏黄灿宋清海 Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Harbin Institute of Technology (Shenzhen) Department of Electrical Engineering City University of Hong Kong Heilongjiang Provincial Key Laboratory of Advanced Quantum Functional Materials and Sensor Devices

Precise control of the polarization state of light on ultrafast time scales plays a key role in revealing the inherent chiral or anisotropic optical responses in various material systems, and it is crucial for applications that require complex polarization encoding. Here, we explore ultrafast polarization control enabled by silicon-based chiral bound state in the continuum（BIC）metasurfaces. By utilizing the intrinsic chiral mode, we achieve high-purity chiral reflection light（S3～-0.92） and rapid modulation（～0.4 ps） of polarization states through all-optical methods. Unlike traditional polarization modulation techniques, our approach leverages the unique advantages of slanted etching dielectric chiral BIC metasurfaces, which facilitate high-Q resonance and exhibit narrow linewidths. These advantages allow swift alterations in polarization states with minimal modulation energy consumption, which should help for greater control of light in integrated photonic applications.

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An Improved UAV Path Optimization Algorithm for Target Accurately and Quickly Localization

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An Improved UAV Path Optimization Algorithm for Target Accur...

2021 International Conference on Information, Cybernetics, and Computational Social systems, ICCSS 2021

作者： Liang, Rui Wu, Kai Xu, Sheng Xu, Tiantian Ma, Xiaoyi Fu, Lianyu City West Power Supply Branch State Grid Tianjin Electric Power Company Tianjin China Shenzhen Institute of Advanced Technology Guangdong Provincial Key Lab of Robotics and Intelligent System Shenzhen China Shenzhen Institute of Advanced Technology Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems Shenzhen China State Grid Tianjin Information Telecommunication Company Tianjin China

ISBN: (纸本)9781665402453

Angle-of-arrival (AOA) target localization using the unmanned aerial vehicle (UAV) has been widely applied in many practical applications. To localize an invasive target quickly and accurately, both the estimation and UAV path optimization algorithms are required. This paper focuses on developing a path optimization method to improve the target estimation performance. Firstly, the problem formulation of AOA target localization is introduced. Secondly, the classical pseudolinear Kalman filter (PLKF) and the gradient-based path optimization are presented. Thirdly, we analyze the problems that existed in the previous methods and propose an improved gradient-descent path optimization algorithm combined with a simple grid search method. Finally, the simulation examples verify the effectiveness of the proposed methods. © 2021 IEEE.

关键词： Unmanned aerial vehicles (UAV)

Uv-Ozone Treated Ti3c2tx-Mxene Nanosheets as Hole Injection Layer for Organic Light-Emitting Diodes

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SSRN 2022年

作者： Lu, Qiqing Wang, Jingkun Miao, Yanqin Guo, Yuanyuan Wang, Guoliang Dong, Jianhua Zhao, Min Wang, Hua Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology Taiyuan030024 China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan030024 China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan030024 China College of Textile Engineering Taiyuan University of Technology Jinzhong030600 China

In this work, we successfully synthesized Ti3C2Tx-MXene nanosheets with a lateral dimension of 1~2 um by using wet-chemical etchant and sonication-assisted liquid-phase exfoliation method. After UV-ozone treatment, the work function for Ti3C2Tx-MXene nanosheets was adjusted to 5.14 eV well matching to indium tin oxide (ITO) anode (4.80 eV). Using Ti3C2Tx-MXene nanosheets as hole injection layer (HIL), Ir(ppy)3-based green organic light-emitting diodes (OLEDs) were fabricated, and the resulting devices exhibit a low turn-on voltage of 3.0 V and the high current efficiency, power efficiency and external quantum efficiency of 72.79 cd/A, 54.44 lm/W and 20.34%, which are obviously better than these of 67.38 cd/A, 50.38 lm/W and 18.65% for PEDOT:PSS-based reference device. Further, FIrpic- and Ir(pq)2acac-based blue and red OLEDs with Ti3C2Tx-MXene nanosheets HIL were demonstrated, which also show the significantly improved device efficiency of 44.56 cd/A, 32.44 lm/W and 22.07% for blue device and 39.17 cd/A, 38.54 lm/W and 21.90% for red device than these for corresponding PEDOT:PSS-based devices, proving the universal applicability of Ti3C2Tx-MXene nanosheets as HIL in OLEDs. The higher performance for Ti3C2Tx-MXene nanosheets-based devices can be attributed to the appropriate work function, high transmittance, high carrier mobility and good film forming property for Ti3C2Tx-MXene nanosheets. This is the first report about the MXene using as HIL in OLEDs, which opens up a new way to develop high-performance holes injection materials for solution-processed OLEDs. © 2022, The Authors. All rights reserved.

关键词： Organic light emitting diodes (OLED)

Spectrum-dependent photonic synapses based on 2D imine polymers for power-efficient neuromorphic computing

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InfoMat 2021年第8期3卷 904-916页

作者： Junyao Zhang Qianqian Shi Ruizhi Wang Xuan Zhang Li Li Jianhua Zhang Li Tian Lize Xiong Jia Huang Interdisciplinary Materials Research Center School of Materials Science and EngineeringShanghai Institute of Intelligent Science and TechnologyTongji UniversityShanghaiPeople's Republic of China Translational Research Institute of Brain and Brain-Like Intelligence Shanghai Fourth People's Hospital Affiliated to Tongji UniversityShanghaiPeople's Republic of China Key Laboratory of Advanced Display and System Application Ministry of EducationShanghai UniversityShanghaiPeople's Republic of China

2D polymers(2DPs)have attracted increasing interests in sensors,catalysis,and gas storage ***,2DPs with unique band structure and tunable photophysical properties also have immense potential for application in photonic neuromorphic ***,photonic synaptic transistors based on 2DPs as the light-tunable charge-trapping medium are developed for the first *** resulted organic transistors can successfully emulate common synaptic functions,including excitatory postsynaptic current,pair-pulse facilitation,the transition of short-term memory to long-term memory,and dynamic *** from the high photosensitivity of the 2DP,the devices can be operated under a low operating voltage of0.1 V,and achieve an ultralow energy consumption of~0.29 pJ per *** addition,the heterostructure formed between the 2DP and organic semiconductor enables spectrum-dependent synaptic responses,which facilitates the simulation of visual learning and memory processes in distinct emotional *** underlying mechanism of spectrum-dependent synaptic-like behaviors is systematically validated with in situ atomic force microscopy based electrical *** spectrum-enabled tunability of synaptic behaviors further promotes the realization of optical logic functions and associative *** work inspires the new application of 2DPs in photonic synapses for future neuromorphic computing.

关键词： 2D polymers neuromorphic computing photonic synapses synaptic functions