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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1115-1125页

作者： Binghui Hu Yu Lei Hang Li ziyi Wang Chao Yu Guozheng Kang Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The nonproportional multiaxial ratchetting of cast AZ91 magnesium (Mg) alloy was examined by performing a sequence of axial-torsional cyclic tests controlled by stress with various loading paths at room temperature (RT).The evolutionary characteristics and path dependence of multiaxial ratchetting were *** illustrate that the cast AZ91 Mg alloy exhibits considerable nonproportional additional softening during cyclic loading with multiple nonproportional multiaxial loading paths;multiaxial ratchetting presents strong path dependence,and axial ratchetting strains are larger under nonproportional loading paths than under uniaxial and proportional45°linear loading paths;multiaxial ratchetting becomes increasingly pronounced as the applied stress amplitude and axial mean stress ***,stress-strain curves show a convex and symmetrical shape in axial/torsional *** ratchetting exhibits quasi-shakedown after certain loading *** abundant experimental data obtained in this work can be used to develop a cyclic plasticity model of cast Mg alloys.

关键词： cast magnesium alloy ratchetting multiaxial loading loading path stress level

A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1424-1437页

作者： Quanbo Ge Yang Cheng Hong Li ziyi Ye Yi Zhu Gang Yao School of Automation Nanjing University of Information Science&TechnologyJiangsu Provincial University Key Laboratory of Big Data Analysis and Intelligent SystemsNanjing University of Information Science&Technologyand the Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)Nanjing University of Information Science&TechnologyNanjing 210044China School of Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China China Classification Society Nantong Office Nantong 226006China Chinese Flight Test Establishment Xi’an 710089China School of Mathematics Tsinghua UniversityBeijing 100084China School of Automation Nanjing University of Information Science&TechnologyNanjing 210044China Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China IEEE

For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity *** the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and *** com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment.

关键词： Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.

A self-centering and stiffness-controlled MEMS accelerometer

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Microsystems & Nanoengineering 2024年第1期10卷 27-40页

作者： Yiming Jin Zhipeng Ma ziyi Ye Mingkang Li Xudong Zheng Zhonghe Jin School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310013China Key Laboratory of Micro/Nano-Satellite Research of Zhejiang Province Hangzhou 310007PR China

This paper presents a high-performance MEMS accelerometer with a DC/AC electrostatic stiffness tuning capability based on double-sided parallel plates(DSPPs).DC and AC electrostatic tuning enable the adjustment of the effective stiffness and the calibration of the geometric offset of the proof mass,respectively.A dynamical model of the proposed accelerometer was developed considering both DC/AC electrostatic tuning and the temperature *** on the dynamical model,a self-centering closed loop is proposed for pulling the reference position of the forceto-rebalance(FTR)to the geometric center of *** self-centering accelerometer operates at the optimal reference position by eliminating the temperature drift of the readout circuit and nulling the net electrostatic tuning *** stiffness closed-loop is also incorporated to prevent the pull-in instability of the tuned low-stiffness accelerometer under a dramatic temperature ***-time adjustments of the reference position and the DC tuning voltage are utilized to compensate for the residue temperature drift of the proposed *** a result,a novel controlling approach composed of a self-centering closed loop,stiffness-closed loop,and temperature drift compensation is achieved for the accelerometer,realizing a temperature drift coefficient(TDC)of approximately 7μg/℃ and an Allan bias instability of less than 1μg.

关键词： stiffness electrostatic centering

Facile access to C-N bonds via unexpected side reactions of Knoevenagel condensation and their application in high-efficiency organic solar cells

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Science China Chemistry 2024年第1期67卷 323-329页

作者： Daobin Yang Shuncheng Yang Hongqian Wang Lin Xie Pengyu Yan ziyi Ge Zhejiang Engineering Research Center for Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The construction of C-N bonds is of great importance in the fields of biology,medicine,chemistry and materials ***,the replacement of organic base from pyridine to piperidine in the Knoevenagel condensation process unexpectedly yields a series of novel organic molecules containing C-N ***,the synthesis method does not require any external transition-metals catalysis,and photo-/***,when the new compound 1b is added as a third component to a well-known binary system of PM6:Y6,the efficiency of the organic solar cell is significantly improved,resulting in an outstanding efficiency of 18.0%,which is one of the highest values reported to date for PM6:Y6-based ternary organic solar cells.

关键词： C-N bonds Knoevenagel condensation cross-coupling reaction third component organic solar cells

Multicolor upconversion reversible modulations in YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) photochromic materials

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Journal of Rare Earths 2024年第2期42卷 270-277,I0002页

作者： Zhen Zhang Peng Li ziyi Xu Zhihao Zhang Qiwei Zhang Haiqin Sun Xihong Hao Inner Mongolia Key Laboratory of Ferroelectric-related New Energy Materials and Devices Schoolof Materials and MetallurgyInner Mongolia University of Science and TechnologyBaotou014010China College of Physics and Technology Guangxi Normal UniversityGuilin541004China

Photochromic materials with multicolor upconversion reversible modulations are attractive in optical switching ***,the fabricated YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) materials exhibit excellent photochromism and multicolor upconversion properties from green,red to near infrared(NIR) emissions with increasing Yb *** multiband upconversion modulations are achieved by alternating light(365 and 405 nm) or thermal *** 365 nm irradiation,the luminescence color changes from yellow to red,the luminescent photoswitching contrast reaches up to 86.21%(green),82.12%(red) and 77.38%(NIR) in the Y_(0.83)Er_(0.01)Tm_(0.01)NbO_(4):0.15 Yb ***,the upconversion emission intensity before and after photochromic reaction shows remarkable change in a wide temperature range of 298-718 *** results indicate that the Er^(3+)/Tm^(3+)/Yb^(3+) tri-doped YNbO_(4) materials can be a good candidate in optical switching and data storage applications.

关键词： Photochromic materials Luminescence modulation Multicolor emission Photoswitching contrast Rare earths

Integrating theory with the nanoreactor concept to synthesize hollow carbon sphere-encapsulated PtNi alloys for enhanced H_(2) generation

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Carbon Energy 2024年第7期6卷 150-162页

作者： Yufeng Wu Minwei Song ziyi Zhao Guang-Hui Wang Changlong Wang Didier Astruc Institute of Circular Economy Faculty of Materials and ManufacturingBeijing University of TechnologyBeijingChina Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoChina ISM UMR CNRS N°5255Universitéde BordeauxTalence CedexFrance

The rational design of efficient bimetallic nanoparticle(NP)catalysts is challenging due to the lack of theoretical understanding of active components and insights into the mechanisms of a specific ***,we report the rational design of nanoreactors comprising hollow carbon sphere-confined PtNi bimetallic NPs(PtNi@HCS)as highly efficient catalysts for hydrogen generation via ammonia borane hydrolysis in *** both density functional theory calculations and molecular dynamics simulations,the effects of an active PtNi combination and the critical synergistic role of a hollow carbon shell on the molecule diffusion adsorption behaviors are *** isotope effects and theoretical calculations allow the clarification of the mechanism,with oxidative addition of an O-H bond of water to the catalyst surface being the rate-determining *** remarkable catalytic activity of the PtNi@HCS nanoreactor was also utilized for successful tandem catalytic hydrogenation reactions,using in situ-generated H_(2) from ammonia borane with high *** concerted design,theoretical calculations,and experimental work presented here shed light on the rational elaboration of efficient nanocatalysts and contribute to the establishment of a circular carbon economy using green hydrogen.

关键词： ammonia borane hydrogen nanoalloy nanoreactor solid catalyst

Method of Single Event Effects Radiation Hardened Design for DC-DC Converter Based Load Transient Detection

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Chinese Journal of Electronics 2024年第5期33卷 1154-1164页

作者： Zhongjie GUO Nan LIU Hu LU Mengli LI ziyi QIU School of Automation and Information Engineering Xi'an University of Technology

Aiming at the impact of load current change on single-event transient, the essential difference between single-event transient and load transient of DC-DC converter is deeply studied. A hardened circuit based on load transient detection is proposed. The circuit detects the load transient information in time and outputs a control signal to control the single event hardened circuit, thereby realizing the improvement of the transient characteristics of the system under dynamic conditions. Based on the 180 nm bipolar-CMOS-DMOS（BCD） process, the design and physical verification of a boost converter are completed. The experimental results show that the input voltage range is 2.9–4.5 V, the output voltage range is 5.8–7.9 V, and the load current is 0–55 mA. During load transients, the load detection circuit turns off the hardened circuit in time, avoiding system oscillation and widening the dynamic range of the hardening circuit. Under the single-event transient, the output voltage fluctuation of the system does not exceed the maximum ripple voltage, and the single-event transient suppression ability reaches more than 86%, the system can work well with linear energy transfer of about 100 Me V·cm2/mg.

关键词： Voltage fluctuations Fluctuations Radiation hardening (electronics) Energy exchange DC-DC power converters Dynamic range Transient analysis DC-DC converter Analog single-event transient effect Load transient detection Radiation hardened by design TMR

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Light-controlled soft bio-microrobot

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Light(Science & Applications) 2024年第3期13卷 531-543页

作者： Jianyun Xiong Xing Li ziyi He Yang Shi Ting Pan Guoshuai Zhu Dengyun Lu Hongbao Xin Guangdong Provincial Key Laboratory of Nanophotonic Manipulation Institute of NanophotonicsJinan University511443 GuangzhouChina

Micro/nanorobots hold exciting prospects for biomedical and even clinical applications due to their small size and high ***,it is still a big challenge to maneuver micro/nanorobots into narrow spaces with high deformability and adaptability to perform complicated biomedical ***,we report a light-controlled soft bio-microrobots(called“Ebot”)based on Euglena gracilis that are capable of performing multiple tasks in narrow microenvironments including intestinal mucosa with high controllability,deformability and *** motion of the Ebot can be precisely navigated via light-controlled polygonal flagellum ***,the Ebot shows highly controlled deformability with different light illumination duration,which allows it to pass through narrow and curved microchannels with high *** these features,Ebots are able to execute multiple tasks,such as targeted drug delivery,selective removal of diseased cells in intestinal mucosa,as well as photodynamic *** light-controlled Ebot provides a new bio-microrobotic tool,with many new possibilities for biomedical task execution in narrow and complicated spaces where conventional tools are difficult to access due to the lack of deformability and bio-adaptability.

关键词： narrow illumination curved

Characteristics and influencing factors of CO_(2) emission from inland waters in China

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Science China Earth Sciences 2024年第6期67卷 2034-2055页

作者： Ting ZHOU Xiaofeng WANG Zuolin XIAO Zhaoyin QING Xianxiang LI Jilong WANG ziyi QUE Chongqing Key Laboratory of Carbon Cycling and Carbon Regulation in Mountainous Ecosystems Chongqing 401331China School of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Chongqing Field Observation and Research Station of Earth Surface Ecological Processes in Three Gorges Reservoir Area Chongqing 405400China School of Earth System Science Tianjin UniversityTianjin 300072China

Inland water bodies,being the most active biogeochemical cycle reactors,play a pivotal role in the global carbon cycle and CO_(2) *** study integrates existing observation dataset of CO_(2) flux(fCO_(2))in rivers,lakes and reservoirs in China,to elucidate their spatial-temporal patterns and key influencing factors and to reappraise the significance for regional carbon *** showed that,the fCO_(2) in rivers,lakes and reservoirs in China presented significant variability with large range of-379.3-4947.6,-160.1-785.0 and -74.0-1603.1 mg CO_(2)m-2h^(-1),*** median of the fCO_(2) in rivers was of 228.5 mg CO_(2)m^(-2)h^(-1),observably higher than these in lakes and reservoirs(26.0 and 28.3 mg CO_(2)m^(-2)h^(-1),respectively).The fCO_(2)in rivers and reservoirs exhibited similar decreasing trend from south to north as a result of universal climate restraint,the averaged fCO_(2) in Pearl River and Yangtze River basins showed much higher than that in Northeastern ***,the averaged fCO_(2) in the Mongolia-Xinjiang lake district and the Northeast lake district were higher than other lake districts,followed by the Qinghai-Xizang lake district,and the Eastern and Yungui lake district were generally low,contradicting the climatic *** water primary production enhancement resulting from human activities was the main driver of spatial variation in the fCO_(2) in ***,the fCO_(2) in rivers presented seasonal pattern with higher wet season than dry season,while opposite patterns were found in lakes and *** temperature,precipitation and water primary production were main ***,it showed pH was a key factor indicating the variability of the fCO_(2) levels either in rivers,lakes or in *** lakes,the fCO_(2) is closely linked to chlorophyll a(Chl-a)and dissolved oxygen(DO),whereas,the fCO_(2) in rivers is primarily associated with organic carbon(OC)and total nitrogen(TN),highlighting the dive

关键词： Rivers/lakes/reservoirs CO_(2) emission Spatio-temporal variability Influence factors Regional contribution

Dendrimer-induced synthesis of porous organosilica capsules for enzyme encapsulation

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 41-48页

作者： ziyi Chu Boyu Zhang Zhenhua Wu Jiaxu Zhang Yiran Cheng Xueying Wang Jiafu Shi Zhongyi Jiang School of Environmental Science&Engineering Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Organic matter-induced mineralization is a green and versatile method for synthesizing hybrid nanostructured materials,where the material properties are mainly influenced by the species of natural biomolecules,linear synthetic polymer,or small molecules,limiting their ***,we adopted dendrimer poly(amidoamine)(PAMAM)as the inducer to synthesize organosilica-PAMAM network(OSPN)capsules for mannose isomerase(MIase)encapsulation based on a hard-templating *** structure of OSPN capsules can be precisely regulated by adjusting the molecular weight and concentration of PAMAM,thereby demonstrating a substantial impact on the kinetic behavior of the MIase@OSPN *** MIase@OSPN system was used for catalytic production of mannose from Dfructose.A mannose yield of 22.24% was obtained,which is higher than that of MIase in organosilica network capsules and similar to that of the free *** overall catalytic efficiency(kcat/Km)of the MIase@OSPN system for the substrate D-fructose was up to 0.556 s^(-1)·mmol^(-1)·***,the MIase@OSPN system showed excellent stability and recyclability,maintaining more than 50% of the yield even after 12 cycles.

关键词： enzyme immobilization enzyme catalysis organosilica networks capsules sugar biosynthesis