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Moisture-resistant,stretchable NO_(x)gas sensors based on laser-induced graphene for environmental monitoring and breath analysis

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Microsystems & Nanoengineering 2022年第4期8卷 91-102页

作者： Li Yang Guanghao Zheng Yaoqian Cao Chuizhou Meng Yuhang Li Huadong Ji xue chen Guangyu Niu Jiayi Yan Ye xue Huanyu cheng State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Health Sciences and Biomedical EngineeringHebei University of TechnologyTianjn 300130China School of Mechanical Engineering Hebei University of TechnologyTianjin 300130China Department of Respiratory and Critical Care Medicine Tianjin Medical University General HospitalTianjin 300052China linstitute of Solid Mechanics Beihang University(BUAA)Beijing 100191China School of Electrical Engineering Hebei University of TechnologyTianjin 300130China school of Architecture and Art Design Hebei University of TechnologyTianjin 300130China Department of Engineering Science and Mechanics The Pennsylvania State UniversityUniversity ParkPA 16802USA

The accurate,continuous analysis of healthcare-relevant gases such as nitrogen oxides(NOx)in a humid environment remains elusive for low-cost,stretchable gas sensing *** study presents the design and demonstration of a moisture-resistant,stretchable NO_(x)gas sensor based on laser-induced graphene(LIG).Sandwiched between a soft elastomeric substrate and a moisture-resistant semipermeable encapsulant,the LIG sensing and electrode layer is first optimized by tuning laser processing parameters such as power,image density,and defocus *** gas sensor,using a needlelike LIG prepared with optimal laser processing parameters,exhibits a large response of 4.18%o ppm^(-1)to NO and 6.66%o ppm^(-1)to NO_(2),an ultralow detection limit of 8.3 ppb to NO and 4.0 ppb to NO_(2),fast response/recovery,and excellent *** design of a stretchable serpentine structure in the LIG electrode and strain isolation from the stiff island allows the gas sensor to be stretched by 30%.Combined with a moisture-resistant property against a relative humidity of 90%,the reported gas sensor has further been demonstrated to monitor the personal local environment during dfferent times of the day and analyze human breath samples to classify patients with respiratory diseases from healthy ***-resistant,stretchable NO_(x)gas sensors can expand the capability of wearable devices to detect biomarkers from humans and exposed environments for early disease diagnostics.

关键词： stretch moisture electrode

Optimization Study on the Blade Profiles of A Horizontal Axis Tidal Turbine Based on BEM-CFD Model

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China Ocean Engineering 2019年第4期33卷 436-445页

作者： ZHANG Da-hai DING Lan HUANG Bin chen xue-meng LIU Jin-tao Ocean College Zhejiang University Zhoushan 316021 China Beijing Institute of Control Engineering Beijing 100190 China

In order to increase the performance of horizontal tidal turbines, a multi-objective optimization model was proposed in this study. Firstly, the prediction model for horizontal tidal turbines was built, which coupled the blade element momentum (BEM) theory and the CFD calculation. Secondly, a multi-objective optimization method coupled the response surface method (RSM) with the multi-objective genetic algorithm NSGA-II was applied to obtain the optimal blade profiles. The pitch angle and the chord length distribution were chosen as the design variables, while the mean power coefficient and the variance of power coefficient were chosen as the objective functions. With the mean power coefficient improved by 4.1% and the variance of power coefficient decreased by 46.7%, results showed that both objective functions could be improved.

关键词： tidal turbine BEM-CFD multi-objective optimization power coefficient

Evaluation of visual quality of spherical and aspherical intraocular lenses by Optical Quality Analysis System

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International Journal of Ophthalmology(English edition) 2017年第6期10卷 914-918页

作者： Yan chen xue Wang Chuan-Di Zhou Qiang Wu Department of Ophthalmology Shanghai Jiao Tong University Affiliated First People＇s Hospital Shanghai 200080 China

AIM： To evaluate the impact of spherical and aspherical intraocular lenses on the postoperative visual quality of age-related cataract patients using Optical Quality Analysis System （OQAS）. METHODS： Seventy-four eyes with age-related cataracts were randomly divided into spherical and aspherical lens implantation groups. Best-corrected visual acuity （BCVA） was measured preoperatively, one day, one week, two weeks, one month and two months after surgery. A biometric systems analysis using the OQAS objective scattering index （OSI） was performed. RESULTS： There were no significant differences in visual acuity （P〉0.05） before and after spherical and aspheric lens implantation. There was a negative linear correction between the OSI value and BCVA （t-=-0.634, P=-0.000）, and positive corrections between the OSI value and the lens LOCUS III value of nucleus color （NC）, nucleus opacity （NO）, cortex （C） and posterior lens capsular （P）（r=0.704, P=0.000; r=0.514, P=0.000; r=0.276, P=0.020; r=0.417, P=-0.000, respectively）. OSI values of spherical vs aspherical lenses were 11.5±3.6 vs 11.8±3.4, 4.1±0.9 vs 3.3±0.8, 3.5±0.9 vs 2.7±0.7, 3.3±0.8 vs 2.6±0.7, 3.2±0.7 vs 2.5±0.8, and 3.2±0.8 vs 2.50.8 before and ld, 1, 2wk, 1 and 2mo after surgery, respectively. All time points varied significantly （P〈0.01） between the two groups. CONCLUSION： Aspherical IOLs does not significantly affect visual acuity compared with spherical IOLs. The OSI value, was significantly lower in the aspherical lens group compared with the spherical lens. This study shows that objective visual quality of aspheric IOLs is better than that of the spherical lens by means of OQAS biological measurement method.

关键词： optical quality analysis system age-relatedcataract spherical lens aspherical lens objective scatteringindex

Diffraction separation and imaging based on double sparse transforms

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Petroleum Science 2022年第2期19卷 534-542页

作者： xue chen Jing-Jie Cao He-Long Yang Shao-Jian Shi Yong-Shuai Guo Hebei Key Laboratory of Strategic Critical Mineral Resources Hebei GEO UniversityShijiazhuangHebei 050031China Hebei Nautral Resources Archives ShijiazhuangHebei 050037China The Third Hydrogeological Engineering Geological Brigade HengshuiHebei 053000China

Reflection imaging results generally reveal large-scale continuous geological information,and it is difficult to identify small-scale geological bodies such as breakpoints,pinch points,small fault blocks,caves,and fractures,*** imaging is an important method to identify small-scale geological bodies and it has higher resolution than reflection *** the common-offset domain,reflections are mostly expressed as smooth linear events,whereas diffractions are characterized by hyperbolic *** paper proposes a diffraction extraction method based on double sparse *** linear events can be sparsely expressed by the high-resolution linear Radon transform,and the curved events can be sparsely expressed by the Curvelet transform.A sparse inversion model is built and the alternating direction method is used to solve the inversion *** data and field data experimental results proved that the diffractions extraction method based on double sparse transforms can effectively improve the imaging quality of faults and other small-scale geological bodies.

关键词： Diffraction separation Common-offset domain Diffraction imaging High-resolution linear Radon transform Curvelet transform Sparse inversion

Pulsar Candidate Classification Using a Computer Vision Method from a Combination of Convolution and Attention

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Research in Astronomy and Astrophysics 2023年第10期23卷 192-200页

作者： Nannan Cai Jinlin Han Weicong Jing Zekai Zhang Dejiang Zhou xue chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of FAST NAOCChinese Academy of SciencesBeijing 100101China Department of Physics Boston CollegeMassachusetts 02467USA

Artificial intelligence methods are indispensable to identifying pulsars from large amounts of *** develop a new pulsar identification system that utilizes the CoAtNet to score two-dimensional features of candidates,implements a multilayer perceptron to score one-dimensional features,and relies on logistic regression to judge the corresponding *** the data preprocessing stage,we perform two feature fusions separately,one for one-dimensional features and the other for two-dimensional features,which are used as inputs for the multilayer perceptron and the CoAtNet *** newly developed system achieves 98.77%recall,1.07%false positive rate(FPR)and 98.85%accuracy in our GPPS test set.

关键词： (stars:)pulsars:general methods:data analysis techniques:image processing

Performance of the CENDL-3.2 and other major neutron data libraries for criticality calculations

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Nuclear Science and Techniques 2022年第1期33卷 81-97页

作者： Bin Zhang Xu-Bo Ma Kui Hu Teng Zhang Xuan Ma Yi-xue chen School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China

Nuclear data are the cornerstones of reactor physics and shielding ***,China released CENDL-3.2 in 2020,and the US released ENDF/B-VIII.0 in ***,it is necessary to comprehensively evaluate the criticality computing performance of these newly released evaluated nuclear *** this study,we used the NJOY2016 code to generate ACE format libraries based on the latest neutron data libraries(including CENDL-3.2,JEFF3.3,ENDF/B-VIII.0,and JENDL4.0).The MCNP code was used to conduct a detailed analysis of fission nuclides,including^(235)U,^(233)U,and^(239)Pu,in different evaluated nuclear data libraries based on 100 *** criticality calculation performance of each library was evaluated using three statistical parameters:δk/σ,χ^(2),and.Analysis of theδk/σparameter showed that CENDL-3.1 and JENDL-4.0 both had>10 benchmarks that exceeded 3r,whereas CENDL3.2,ENDFB-VIII.0,and JEFF-3.3 had,7,5,and 4 benchmarks,respectively,exceeding *** ENDF/B-VII.1 library performed best,with only two benchmarks exceeding *** to CENDL-3.1,CENDL-3.2 offers an improvement in criticality *** to the JEFF-3.3 and ENDF/B-VIII.0 libraries,CENDL3.2 performs better in the calculation of the^(233)U assemblies,but it performs poorly in the pusl11 series case calculation of the^(239)Pu assemblies,and thus further improvement is needed.

关键词： Criticality calculations CENDL-3.2 ENDF/B-VIII.0 Neutron ACE library

Modelling of the Self Sum-Frequency-Mixing Laser

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Chinese Physics Letters 2001年第2期18卷 230-232页

作者： chen xue-Yuan LUO Zun-Du HUANG Yi-Dong Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002

A theoretical model of the self sum-frequency-mixing(SFM)laser generated by a single crystal is proposed,in which spatial distribution of the pump and circulating fundamental lasers with arbitrary beam waists are taken into *** model is then applied to two kinds of crystals of current interest,Nd:YAI_(3)(BO_(3))_(4) and Nd:Ca_(4)GdO(BO_(3))_(3).Numerical analyses of the self-SFM laser properties predict and confirm some experimental *** model proposed is not limited to self-SFM lasers and may be applied to general analyses of the fundamental or nonlinear laser generation with Gaussian beams.

关键词： Nd: pump laser

Nanowire-based synaptic devices for neuromorphic computing

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Materials Futures 2023年第2期2卷 94-108页

作者： xue chen Bingkun chen Pengfei Zhao Vellaisamy A L Roy Su-Ting Han Ye Zhou Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060People’s Republic of China College of Physics and Optoelectronic Engineering Harbin Engineering UniversityHarbin 150001People’s Republic of China School of Science and Technology Hong Kong Metropolitan UniversityHong KongSARPeople’s Republic of China College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Institute for Advanced Study Shenzhen UniversityShenzhen 518060People’s Republic of China

The traditional von Neumann structure computers cannot meet the demands of high-speed big data processing;therefore,neuromorphic computing has received a lot of interest in recent ***-inspired neuromorphic computing has the advantages of low power consumption,high speed and high *** human brains,the data transmission and processing are realized through *** synaptic devices can be adopted to mimic the biological synaptic ***(NW)is an important building block for nanoelectronics and optoelectronics,and many efforts have been made to promote the application of NW-based synaptic devices for neuromorphic ***,we will introduce the current progress of NW-based synaptic memristors and synaptic *** applications of NW-based synaptic devices for neuromorphic computing will be *** challenges faced by NW-based synaptic devices will be *** hope this perspective will be beneficial for the application of NW-based synaptic devices in neuromorphic systems.

关键词： nanowires synapse memristor transistor neuromorphic computing

Solderability and intermetallic compounds formation of Sn-9Zn-xAg lead-free solders wetted on Cu substrate

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Rare Metals 2009年第6期28卷 656-660页

作者： chen Wenxue xue Songbai WANG Hui WANG Jianxin HAN Zongjie College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The eutectic Sn-9Zn alloy was doped with Ag （0 wt.%-1 wt.%） to form Sn-9Zn-xAg lead-free solder alloys. The effect of the addition of Ag on the microstructure and solderability of this alloy was investigated and intermetallic compounds （IMCs） formed at the solder/Cu interface were also examined in this study. The results show that, due to the addition of Ag, the microstructure of the solder changes. When the quantity of Ag is lower than 0.3 wt.%, the needle-like Zn-rich phase decreases gradually. However, when the quantity of Ag is 0.5 wt.%-1 wt.%, Ag-Zn intermetallic compounds appear in the solder. In particular, adding 0.3 wt.% Ag improves the wetting behavior due to the better oxidation resistance of the Sn-9Zn solder. The addition of an excessive amount of Ag will deteriorate the wetting property because the gluti- nosity and fluidity of Sn-9Zn-（0.5, 1）Ag solder decrease. The results also indicate that the addition of Ag to the Sn-Zn solder leads to the precipitation of ε-AgZn3 from the liquid solder on preformed interracial intermetallics （CusZn8）. The peripheral AgZn3, nodular on the Cu5Zn8 IMCs layer, is likely to be generated by a peritectic reaction L ＋ γ-Ag5Zns→AgZn3 and the following crystallization of AgZn3.

关键词： soldering materials lead-free solder wettability intermetallic compounds