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Nano research 2023年第5期16卷 6859-6869页

作者： Jue Huang Keren Dai Yajiang Yin Zhaorong Chen Xiaofeng Wang Zheng You Department of Precision instrument Tsinghua UniversityBeijing 100084China Beijing advanced Innovation center for Integrated Circuits Beijing 100084China ZNDY of Ministerial Key Laboratory School of Mechanical EngineeringNanjing University of Science and TechnologyNanjing 210094China

Supercapacitors(SCs)have been successfully used in electric vehicles or military equipment systems for their high power ***,the mechanical impacts from vehicle crashes and missile penetration probably cause performance fluctuations or failure of SCs,which may threaten the safety of systems using *** this paper,a generalized circuit model to analyze the transient process of SCs under mechanical loads is *** circuit model simultaneously takes capacitance change,internal short-circuit and resistance change into account,an extra resistor-capacitor circuit(RCC)is added to simulate the nonlinear behavior during charging and ***,the relationships between pressure and fundamental circuit parameters are determined by static *** taking the static test data into the circuit model,the transient response of different types of SCs under particular mechanical loading conditions is ***,the influences of some crucial parameters on the voltage responses of SCs are revealed based on the simulations,which provide references for designing and optimizing mechanical load-resistant or self-sensing SCs in specific application scenarios.

关键词： supercapacitors equivalent circuit transient response resistor-capacitor circuit mechanical loads

CdS quantum dot sensitized p-type NiO as photocathode with integrated cobaloxime in photoelectrochemical cell for water splitting

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Chinese Chemical Letters 2015年第1期26卷 141-144页

作者： Yong Na Bo Hu Qiu-Ling Yang Jian Liu Li Zhou Rui-Qing Fan Yu-Lin Yang Department of Chemistry Harbin Institute of Technology center of Ultra-Precision Optoelectronic instrument engineering Harbin Institute of Technology

CdS sensitized NiO electrode was used as the photoactive cathode in a photoelectrochemical cell for water splitting,avoiding the use of a sacrificial electron *** increment under visible light irradiation was observed after integration of[Co（dmgH）_2（4-Me-py）Cl]（1） to the photocathode,suggesting 1 could accept electrons from photoexcited CdS for water reduction and NiO could move the holes in the valence band of CdS to anode for water oxidation.

关键词： Quantum dot Photocathode Cobaloxime Photoelectrochemical cell Water splitting

Work Hardening Behavior of 1020 Steel During Cold-Beating Simulation

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Chinese Journal of Mechanical engineering 2017年第2期30卷 321-331页

作者： Fengkui CUI Yuanfei LING Jinxue XUE Jia LIU Yuhui LIU Yan LI School of Mechatronics engineering Henan University ofScience and TechnologyLuoyang 471003China Collaborative Innovation center of Machinery Equipment advanced Manufacturing of Henan Province Henan University of Science and TechnologyLuoyang 471003China School of Mechanical and Precision instrument engineering Xi'an University of Technology Xi'an 710048China

The present research of cold-beating formation mainly focused on roller design and manufacture, kinematics, constitutive relation, metal flow law, thermo-mechanical coupling, surface micro-topography and microstructure evolution. However, the research on surface quality and performance of workpieces in the process of cold-beating is rare. Cold-beating simulation experiment of 1020 steel is conducted at room temperature and strain rates ranging from 2000 to 4000 s^-1 base on the law of plastic forming. According to the experimental data, the model of strain hardening of 1020 steel is established, Scanning Electron Microscopy（SEM） is conducted, the mechanism of the work hardening of 1020 steel is clarified by analyzing microstructure variation of 1020 steel. It is found that the strain rate hardening effect of 1020 steel is stronger than the softening effect induced by increasing temperatures, the process of simulation cold-beating cause the grain shape of 1020 steel significant change and microstructure elongate significantly to form a fibrous tis- sue parallel to the direction of deformation, the higher strain rate, the more obvious grain refinement and the more hardening effect. Additionally, the change law of the work hardening rate is investigated, the relationship between dislocation density and strain, the relationship between work hardening rate and dislocation density is obtained. Results show that the change trend of the work hardening rate of 1020 steel is divided into two stages, the work hardening rate decreases dramatically in the first stage and slowly decreases in the second stage, finally tending toward zero. Dislocation density increases with increasing strain and strain rate, work hardening rate decreases with increasing dislocation density. The research results provide the basis for solving the problem of improving the surface quality and performance of workpieces under cold-beating formation of 1020 steel.

关键词： 1020 steel Cold·beating Work hardening Grain Dislocation density

The intervention effects of Lactobacillus casei LC2W on Escherichia coli O157:H7-induced mouse colitis

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Food Science and Human Wellness 2020年第3期9卷 289-294页

作者： Guangqiang Wang Hongyu Tang Ying Zhang Xiang Xiao Yongjun Xia Lianzhong Ai Shanghai engineering research center of Food Microbiology School of Medical Instrument and Food EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Food and Biological engineering Jiangsu UniversityZhenjiang 212013China

This study investigated the intervention effects of Lactobacillus casei LC2W in murine(SPF C57BL/c)challenge infection models induced by Escherichia coli O157:*** were fed streptomycin with water for 3 days prior to intragastric gavage by *** O157:H7(Control)or *** LC2W together with *** O157:H7(Intervention)to explore the role of *** LC2W by biochemical indicators,histological evaluation,expression of colonic pro-inflammatory and intestinal barrier factors related to *** showed that the administration of *** LC2W was able to alleviate the symptoms of colitis induced by *** O157:H7,exhibiting lower weight loss as well as more intact colon ***,*** LC2W could down-regulate the expression of pro-inflammatory cytokines(TNF-α,IL-6,and IL-1β)and protect the intestinal barrier function by improving the level of MUC2,ZO-1 and E-cadherin 1 compared to the control *** results demonstrate that *** LC2W can reduce the severity of *** O157:H7 infection,and suggest *** LC2W may maintain the immune balance and intestinal barrier to reduce *** addition,we found the effect of intervention is similar to that of prevention,which is better than that of treatment.

关键词： Probiotics Lactobacillus casei LC2W Intervention Escherichia coli O157:H7

High-Efficiency Dynamic Terahertz Deflector Utilizing a Mechanically Tunable Metasurface

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research 2024年第3期2023卷 585-594页

作者： Zhenci Sun Chao Liang Chen Chen Xiayu Wang Enze Zhou Xiaomeng Bian Yuanmu Yang Rui You Xiaoguang Zhao Jiahao Zhao Zheng You Department of Precision instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and instruments Tsinghua UniversityBeijing 100084China Beijing advanced Innovation center for Integrated Circuits Beijing 100084China School of instrument Science and Opto-Electronic engineering Beijing Information Science and Technology UniversityBeijing 100016China.

Terahertz (THz) wave manipulation, especially the beam deflection, plays an essential role in various applications, such as next-generation communication, space exploration, and high-resolution imaging. Current THz optical components and devices are hampered by their large bulk sizes and passive responses, limiting the development of high-performance, miniaturized THz microsystems. Tunable metasurfaces offer a powerful dynamic optical platform for controlling the propagation of electromagnetic waves. In this article, we presented a mechanically tunable metasurface (MTM), which can achieve terahertz beam deflection and vary the intensity of the anomalous reflected terahertz wave by changing the air gap between the metallic resonator (MR) array with phase discontinuities and Au ground plane. The absence of lossy spacer materials substantially enhances deflection efficiency. The device was fabricated by a combination of the surface and bulk-micromachining processes. The THz beam steering capability was characterized using terahertz time domain spectroscopy. When the air gap is 50 μm, the maximum deflection coefficient reaches 0.60 at 0.61 THz with a deflection angle of ~44.5°, consistent with theoretical predictions. We further established an electrically tunable miniaturized THz device for dynamic beam steering by introducing a micro voice coil motor to control the air gap continuously. It is shown that our designed MTM demonstrates a high modulation depth of deflection coefficient (~ 62.5%) in the target steered angle at the operating frequency. Our results showcase the potential of the proposed MTM as a platform for high-efficiency THz beam manipulation.

关键词： tunable Efficiency resonator

Angle robust transmitted plasmonic colors with different surroundings utilizing localized surface plasmon resonance

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Chinese Physics B 2023年第7期32卷 226-233页

作者：高旭峰王琦张世杰洪瑞金张大伟 Shanghai Key Laboratory of Modern Optic Systems Engineering Research Center of Optical Instrument and SystemMinistry of Education and Shanghai Key Laboratory of Modern Optical SystemsSchool of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

Color filters in different surroundings inherently suffer from angular sensitivity,which hinders their practical ***,we present an angle-insensitive plasmonic filter that can produce different color responses to different surrounding *** color filters are based on a two-dimensional periodically and randomly distributed silver nanodisk array on a silica *** proposed plasmonic color filters not only produce bright colors by altering the diameter of the Ag nanodisk,but also achieve continuous color palettes by changing the surrounding *** to the weak coupling between the metallic nanodisks,the plasmonic color filters can enable good incident angle-insensitive properties(up to 30°).The strategy presented here could exhibit robust and promising applicability in anti-counterfeiting and imaging technologies.

关键词： plasmonic color filter color sensing high angular tolerance

Design and fabrication of metal spherical conformal thin film multisensor for high-temperature environment

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Chinese Journal of Aeronautics 2024年第11期37卷 535-547页

作者： Lida XU Xiong ZHOU Yong HUANG Yusen WANG Chenhe SHAO Yuelong LI Lingyun WANG Qingtao YANG Daoheng SUN Qinnan CHEN Discipline of Intelligent instrument and Equipment Pen-Tung Sah Institute of Micro-Nano Science and TechnologyXiamen UniversityXiamen 361102China Fujian Micro/nano Manufacturing engineering Technology research center Xiamen UniversityXiamen 361102China China Aerodynamics research and Development center Mianyang 621000China

Conformal thin-film sensors enable precise monitoring of the operating conditions of components in extreme ***,the development of these sensors encounters major challenges,especially in uniformly applying multiple film layers on complex metallic surfaces and accurately capturing diverse operational *** work reports a multi-sensor design and multi-layer additive manufacturing process targeting spherical metallic *** proposed high-temperature dip-coating and self-leveling fabrication process achieves high-temperature thin-film coatings with excellent uniformity,high-temperature electrical insulation,and adhesion *** fabricated Ag/Pt thin film thermocouple arrays and a heat flux sensor exhibit a maximum temperature resistance of up to 960℃,with thermoelectric potential outputs and hightemperature resistance closely mirroring those of wire-based Ag/Pt *** environmental testing was conducted using high-power lasers and a flame *** results show that the array of thin-film conformal thermocouples more accurately reflected temperature changes at different points on a spherical *** heat flux sensors achieve responses within 95 ms and with-stand environments with heat fluxes over 1.2 MW/m^(2).The proposed multi-sensor design and fabrication method offers promising monitoring applications in harsh environments,including aerospace and nuclear power.

关键词： Conformal thin-film sensor Metallic spherical surfaces Multi-sensor perception Harsh environments Additive manufacturing

Synthesis and Crystal Structure of a New Guanidinatoaluminium Complex and Its Utilityin the Meerwein-Ponndorf-Verley Reduction

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Chinese Journal of Structural Chemistry 2018年第4期37卷 624-630页

作者：韩红斐李文娟张少峰魏学红 Department of Chemistry Taiyuan Normal University The School of Chemistry and Chemical engineering Shanxi University Scientific instrument center Shanxi University

The treatment of pyrrolidine （C4HsNI-I） with sequentially trimethylaluminum andcarbodiimide CyN--C=NCy in a molar ratio of 1 ：1：1 in the presence of O2 afforded a newguanidinatoaluminurn complex, [{（C4HsN）C（NCy）2}AIMe（/I-OMe）]2 （1）, which was characterizedby elemental analyses, 1H, 13C NMR spectra and single-crystal X-ray diffraction analysis. ComplexI crystallizes in monoclinic, space group P21/c with a = 9.8330（9）, b = 8.5786（8）, c = 24.159（2） A,β= 92.927（2）°, V= 2035.3（3） A3, Dc = 1.141 g cm^-3, F（000） = 768 and μ= 0.110 mm^-l. In addition,complex 1 was used to catalyze the Meerwein-Ponndorf-Verley （MPV） reduction and 1 as apre-catalyst at low catalyst loadings （5 tool%） exhibited good catalytic activity for the reduction ofa series of aldehydes to the corresponding alcohols in good yields （cony. up to 99%）.

关键词： guanidinatoaluminium complex synthesis crystal structure MPV reaction

Photo-induced flexible semiconductor CdSe/CdS quantum rods alignment

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Journal of Semiconductors 2023年第9期44卷 83-89页

作者： Wanlong Zhang Julian Schneider Maksym F.Prodanov Valerii V.Vashchenko Andrey L.Rogach Xiaocong Yuan Abhishek K.Srivastava nanophotonics research center Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China State Key Laboratory of advanced Displays and Optoelectronics Technologies Department of Electronic&Computer EngineeringHong Kong University of Science and TechnologyHong Kong SARChina Department of Materials Science and engineering and Centre for Functional Photonics(CFP) City University of Hong KongHong Kong SARChina

The anisotropic absorption and emission from semiconductor CdSe/CdS quantum rods(QRs)provide extra benefits among other photoluminescence *** photo-induced alignment technique,the QRs can be oriented in liquid crystal polymer matrix at a large *** this article,a 2D Dammann grating pattern,within“SKL”characters domains aligned QRs in composite film,was fabricated by multi-step photo exposure using several photo masks,and a continuous geometric lens profile pattern aligned QRs was realized by the single step polarization converting holographic irradiation *** polarized optical microscope and fluorescence microscope are employed to determine the liquid crystal director profiles and QRs anisotropic excitation *** have been able to orient the QRs in fine binary and continuous patterns that confirms the strong quantum rod aligning ability of the proposed ***,the proposed approach paves a way for photoinduced flexible QRs alignments to provide a highly specific and difficult-to-replicate security application at a large scale.

关键词： quantum rods photo alignment liquid crystal flexible alignment polarized emission

Installation error calibration for MEMS angular measurement system in hypersonic wind tunnel

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Chinese Journal of Aeronautics 2023年第5期36卷 175-186页

作者： Xiong WANG Xueling ZHAO Bin ZHOU Qi WEI Rong ZHANG Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China Department of Precision instrument Tsinghua UniversityBeijing 100084China

The accuracy of model attitude measurement has an important impact on wind tunnel test results. Microelectromechanical System Inertial Measurement Unit(MEMS IMU) provides a feasible way to measure model attitudes with high accuracy. However, the installation error between MEMS IMU coordinate system and the body coordinate system of test models can make the accuracy of the model attitude measurement decrease. In wind tunnel tests, the installation error depends on the relationship between the IMU and the model mechanism before tests. Therefore, infield calibration in wind tunnel tests is necessary to reduce installation errors. To improve attitude measurement accuracy, the least squares quaternion calibration method based on MEMS IMU and six-position calibration procedure are proposed. High-precision three-axis turntable tests are performed. The pitch accuracy after calibration is higher than that before calibration in the angle of attack sweeping tests. The Root-Mean-Square Errors(RMSE) in the roll and yaw are within0.01°, which are smaller than those before calibration. In the roll sweeping tests, RMSE of three attitude angles decrease significantly. In hypersonic wind tunnel tests, the pitch errors before and after calibration are within 0.05° and 0.02° in the angle of attack sweeping tests without wind. In five angle of attack sweeping tests with wind, the deviation between the mean of the pitch and the pitch after the elastic angle correction is within 0.03° and the standard deviation of five tests is within 0.01°. The proposed method is confirmed to enhance the accuracy of attitude measurement effectively, which is convenient for engineering applications.

关键词： Calibration Installation error Least squares MEMS Model attitude measurement Quaternion Wind tunnel test