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基于信息技术的自动修剪机参数监控与分析

农机化研究 2022年第1期44卷 208-212页

作者：杨正张鹏河北能源职业技术学院河北唐山063000

以自动修剪机运行参数监控系统为研究对象,基于信息采集技术,搭建一种通过位置传感器、角度传感器实现的运行过程参数监控系统。修剪机自动工作过程中,参数监控系统进行修剪机运行参数采集,并与控制系统中的设定值进行比对,进行插补控... 详细信息

以自动修剪机运行参数监控系统为研究对象,基于信息采集技术,搭建一种通过位置传感器、角度传感器实现的运行过程参数监控系统。修剪机自动工作过程中,参数监控系统进行修剪机运行参数采集,并与控制系统中的设定值进行比对,进行插补控制指令修正,实现修剪机运行过程的闭环控制。系统运行参数采集分析表明:自动修剪机运行过程中的转动角度、位移、速度及加速度等参数与系统设定值基本相符,但随着修剪过程的推移,实际运行参数与系统初始设定值之间偏差会逐渐增大。

关键词：自动修剪机信息采集技术过程参数

Fixed-Time Adaptive Time-Varying Matrix Projective Synchronization of Time-Delayed Chaotic Systems with Different Dimensions

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1451-1463页

作者： Peng ZHENG Xiaozhen Guo Guoguang Wen Department of Computer Science University of LiverpoolLiverpoolL693BXUK ORDOS No.1 High School East Campus Erdos017010China Department of Mathematics Beijing Jiaotong UniversityBeijing100044China

This paper deals with the fixed-time adaptive time-varying matrix projective synchronization(ATVMPS)of different dimensional chaotic systems(DDCSs)with time delays and unknown parameters.Firstly,to estimate the unknown parameters,adaptive parameter updated laws are designed.Secondly,to realize the fixed-time ATVMPS of the time-delayed DDCSs,an adaptive delay-unrelated controller is designed,where time delays of chaotic systems are known or unknown.Thirdly,some simple fixed-time ATVMPS criteria are deduced,and the rigorous proof is provided by employing the inequality technique and Lyapunov theory.Furthermore,the settling time of fixed-time synchronization(Fix-TS)is obtained,which depends only on controller parameters and system parameters and is independent of the system’s initial states.Finally,simulation examples are presented to validate the theoretical analysis.

关键词： Time-varying matrix projective synchronization(TVMPS) fixed-time control unknown parameters different dimensions time-delayed chaotic systems(TDCSs)

Detection of weak non-covalent cation-π interactions in NGAL by single-molecule force spectroscopy

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Nano Research 2022年第5期15卷 4251-4257页

作者： Jingyuan Nie Yibing Deng Fang Tian Shengchao Shi Peng ZHENG State Key Laboratory of Coordination Chemistry Chemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing University163 Xianlin RoadNanjing 210023China

Cation-π interaction is an electrostatic interaction between a cation and an electron-rich arene.It plays an essential role in many biological systems as a vital driving force for protein folding,stability,and receptor-ligand interaction/recognition.To date,the discovery of most cation-π interactions in proteins relies on the statistical analyses of available three-dimensional(3D)protein structures and corresponding computational calculations.However,their experimental verification and quantification remain sparse at the molecular level,mainly due to the limited methods to dynamically measure such a weak non-covalent interaction in proteins.Here,we use atomic force microscopy-based single-molecule force spectroscopy(AFM-SMFS)to measure the stability of protein neutrophil gelatinase-associated lipocalin(also known as NGAL,siderocalin,lipocalin 2)that can bind iron through the cation-π interactions between its three cationic residues and the iron-binding tri-catechols.Based on a site-specific cysteine engineering and anchoring method,we first characterized the stability and unfolding pathways of apo-NGAL.Then,the same NGAL but bound with the iron-catechol complexes through the cation-π interactions as a holo-form was characterized.AFM measurements demonstrated stronger stabilities and kinetics of the holo-NGAL from two pulling sites,F122 and F133.Here,NGAL is stretched from the designed cysteine close to the cationic residues for a maximum unfolding effect.Thus,our work demonstrates high-precision detection of the weak cation-π interaction in NGAL.

关键词： cation-Tr interaction neutrophil gelatinase-associated lipocalin(NGAL) single-molecule force spectroscopy atomic force microscopy(AFM)

Systematic evaluation of advance in application and discharge mechanism of solution electrode glow discharge

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Chinese Chemical Letters 2022年第1期33卷 61-70页

作者： Xiaoxu peng zheng Wang Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

As a kind of microplasma sustained in air,solution electrode glow discharge(SEGD)ignited between the liquid electrode and metal electrode is attractive to the fields of optical emission spectrometry and mass spectrometry due to its unique advantages,such as low power consumption and low carrier gas consumption.Moreover,the complex and efficient reactions in the liquid phase and plasma phase of SEGD make it considerable research potential in the fields of biology and medicine,material synthesis,electrochemistry.Considering the close relationship between the various fields on SEGD,here we are devoted to provide an overview of the development of SEGD in various fields.More importantly,a systematic discussion on the discharge mechanism is conducted based on the research process in various fields for getting deeper insight into the SEGD.

关键词： Solution cathode glow discharge Solution anode glow discharge Mass spectrometry Optimal emission spectroscopy Discharge mechanism

An atmosphere-breathing propulsion system using inductively coupled plasma source

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Chinese Journal of Aeronautics 2023年第5期36卷 223-238页

作者： Peng ZHENG Jianjun WU Yu ZHANG Bixuan CHE Yuanzheng ZHAO College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

CubeSats have attracted more research interest recently due to their lower cost and shorter production time.A promising technology for CubeSat application is atmosphere-breathing electric propulsion,which can capture the atmospheric particles as propulsion propellant to maintain longterm mission at very low Earth orbit.This paper designs an atmosphere-breathing electric propulsion system for a 3 U CubeSat,which consists of an intake device and an electric thruster based on the inductively coupled plasma.The capture performance of intake device is optimized considering both particles capture efficiency and compression ratio.The plasma source is also analyzed by experiment and simulation.Then,the thrust performance is also estimated when taking into account the intake performance.The results show that it is feasible to use atmosphere-breathing electric propulsion technology for CubeSats to compensate for aerodynamic drag at lower Earth orbit.

关键词： Atmosphere-Breathing Electric Propulsion(ABEP) CubeSat Inductively coupled plasma Intake device Very Low Earth Orbit(VLEO)

Soil type and wetting intensity control the enhancement extent of N_(2)O efflux in soil with drought and rewetting cycles

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International Soil and Water Conservation Research 2024年第1期12卷 137-144页

作者： Panpan Jiao Lei Yang Zhongwu Li Peng ZHENG Xiaodong Nie School of Geographical Sciences Hunan Normal UniversityChangsha 410081China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau The Research Center of Soil and Water Conservation and Ecological EnvironmentChinese Academy of Sciences and Ministry of EducationYangling 712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Climate change alters the intensity and frequency of drought and rewetting(D/W)events;however,the influence patterns of D/W on soil N_(2)O efflux in the water-limited area were not fully understood.Therefore,the impacts of D/W cycles varying in different extent of rewetting and frequency to N_(2)O efflux in two kinds of soil on the Loess Plateau were investigated.The incubation conditions consisted of 1)D/W treatments with four 7-day cycles from 10%water holding capacity(WHC)to 60%WHC or 90%WHC,2)constant moisture of 60%WHC and 90%WHC.The pulse of N_(2)O efflux rate under 10-60%WHC treatment was higher than that under 10-90%WHC treatment in calcic cambisols,while opposite trend was observed in earth-cumuli-orthic anthrosols.Meanwhile,the pulse of N_(2)O efflux rate decreased as cycle number increased for different wetting intensities and soil types.The direct N_(2)O efflux under 10-60%WHC and 10-90%WHC treatments were 5.49 and 1.89μg N_(2)O-N g^(-1)soil in calcic cambisols,with those being 1.92 and 10.85μg N_(2)O-N g^(-1)soil in earth-cumuli-orthic anthrosols,respectively.The N loss in earth-cumuli-orthic anthrosols was approximately 5.74 times greater than that in calcic cambisols under 10-90%WHC treatment,whereas the N loss under 10-60%WHC treatment was about 2.86 times greater in calcic cambisols than that in earth-cumuli-orthic anthrosols.This study suggested that extreme rainfall events can enhance the N_(2)O efflux and N loss in agricultural soils on the Loess Plateau in terms of soil type and wetting intensity,which should not be ignored in the N fertilizer management.

关键词： Drought/rewetting cycles N_(2)O efflux Wetting intensity Microbial biomass N Dissolved organic N Loess plateau

Structural features of 18R-type long-period stacking ordered phase in Mg85Zn6Y9 alloy and the Ni doping effect on its hydrogen storage properties

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Journal of Materials Science & Technology 2023年第14期145卷 148-155页

作者： Zhiwen zheng Cong peng Qingan Zhang School of Materials Science and Engineering Anhui University of TechnologyMaanshanAnhui 243002China

Magnesium-based alloys with 18R-type long-period stacking ordered(LPSO)structures have attracted wide attention for structural and functional applications.To understand hydrogen storage properties of 18R phase,the Mg_(85)Zn_(6)Y_(9)alloy with 94 wt.%of 18R-type LPSO phase is prepared in this work.The 18R phase has a layered structure where Y-Zn-Mg and Mg layers alternately stack along the c-axis.In the Y-Zn-Mg layers,Y,Zn and partial Mg sites are co-occupied by Y and Mg,Zn and Mg,and Mg and Zn/Y atoms,respectively.Thus the 18R phase is easily decomposed intoα-MgH_(2),γ-MgH_(2),YH_(2),YH_(3),C14-type Laves phase MgZn_(2)and minor CsCl-type Y(Mg,Zn)during ball milling under hydrogen atmosphere.Af-ter further hydrogen absorption-desorption cycling,Y(Mg,Zn)disappears gradually and C14 phase trans-forms into C15-type Laves phase.By contrast,the Mg_(85)Zn_(6)Y_(9)alloy has better hydrogen storage kinetics and cycle durability than pure Mg because of the catalytic effect of YH_(2)/YH_(3)on hydrogen absorption-desorption and inhibition role of Laves phase in Mg crystallite growth.Moreover,the introduction of Ni into Mg_(85)Zn_(6)Y_(9)sample leads to a further decrease in activation energy of hydrogen desorption from 106.39 to 96.78 kJ mol−1 due to the formation of Mg_(2)Ni.This work not only provides new insights into structural features and hydrogen storage characteristics of 18R phase but offers an effective method for improving hydrogen storage properties.

关键词： Mg-based alloy Magnesium hydride Crystal structure Hydrogen storage

Overriding the inherent alkalinity to dual phosphinito bimetallic catalyst for C(sp^(2))-C(sp^(3))formation:A combined computational and experimental study

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中国化学快报:英文版 2023年第8期34卷 147-152页

作者： Sujuan zheng Heng Zhang Qian peng State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Laboratory of Biosensing and Molecular RecognitionFrontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformation Tianjin 300192China

Unraveling the catalytic reaction mechanism is a long-term challenge for developing efficient catalysts.The blooming bimetallic catalyst have enabled to activate inert bonds and realize complex C-C formation.Herein,we theoretically discover a dual-phosphinito bridged hetero-bimetallic species that verified by NMR experiments.Our results indicate only dual-phosphinito Ni-Al model can be an active catalyst in asymmetric cycloadditions via C-C activation and C-H activation,which can well rationalize the experimental observations for both reactivity and stereo-selectivity.An unprecedented tandem redox dehydrogenation mechanism was revealed to control the formation of this active species overriding the inherent basicity.Synergistic Lewis acid and eg orbital interactions,including dz2 orbital reoccupation and d_(x^(2)−y^(2))orbital recombination,were disclosed to understand both thermodynamic and kinetic advance of dual-bridged model,displaying feasible redox properties.

关键词： Ni-Al bimetallic catalysis Secondary phosphine oxides Redox dehydrogenation Dual-SPO model

Simulation of RFI Cancellation Using Subspace Projection Algorithm for PAF Receiver

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Research in Astronomy and Astrophysics 2024年第1期24卷 237-244页

作者： peng Wu Jian Li Mao-zheng Chen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The simulation of radio frequency interference(RFI) cancellation by applying a spatial filtering technique for phased array feed(PAF) is presented. In order to better reflect the characteristics of PAF, a new signal model is to add the coupling coefficient among elements of PAF to the conventional array signal model. Then the subspace projection(SP) algorithm is used to cancel RFI from the correlation matrix of the signal, and finally, the 2D power image is drawn. The power variation of signal-of-interest direction and RFI direction before and after using the SP algorithm is analyzed. The new signal model and simulation strategy can be used to test and verify the beamformer.

关键词： methods:analytical techniques:radar astronomy telescopes