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单轨吊起吊马达先导式电液比例同步控制仿真分析

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机床与液压 2022年第24期50卷 130-135页

作者：张丽穆洪云刘尧四川化工职业技术学院四川泸州646000 贵州大学机械工程学院贵州贵阳550025 六盘水师范学院矿业与土木工程学院贵州六盘水553000

为了克服单轨吊偏载起吊和负载波动工况,提高设备的安全性,提出一种单轨吊起吊马达Fuzzy-PID同步控制系统。分析该系统液压工作原理,选择主从同步控制策略;在AMESim和Simulink中建模;进行联合仿真,并与PID进行比较,分析系统的同步性和... 详细信息

为了克服单轨吊偏载起吊和负载波动工况,提高设备的安全性,提出一种单轨吊起吊马达Fuzzy-PID同步控制系统。分析该系统液压工作原理,选择主从同步控制策略;在AMESim和Simulink中建模;进行联合仿真,并与PID进行比较,分析系统的同步性和鲁棒性。仿真结果表明:单轨吊起吊马达采用Fuzzy-PID是切实可行的,与PID相比具有响应速度快,超调量小,鲁棒性好的优点。Fuzzy-PID在偏载起吊时,系统在0.8 s内达到稳定转速,相对于PID提高了42.1%;最大同步误差为35 r/min,相对于PID降低了27.1%;稳定后同步误为0.6 r/min,相对于PID降低了40%。负载波动时,系统在0.4 s内达到稳定转速,相对于PID提高了42.9%;最大同步误差为13 r/min,相对于PID降低了9%。故Fuzzy-PID可以有效解决起吊马达偏载起吊和负载波动工况,能保证单轨吊起吊动作平稳、同步、安全进行。

关键词：起吊马达模糊PID 同步控制联合仿真

不确定性下基于多工况优化的可控性换热器网络综合

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化工学报 2020年第3期71卷 1154-1162页

作者：李晨莹刘琳琳张磊顾偲雯都健大连理工大学化工学院化工系统工程研究所辽宁大连116024

换热器网络在化工生产过程中起着能量回收、节能降耗的重要作用。常规换热器网络综合方法以经济性为目标进行参数和结构优化,导致换热设备之间的强烈耦合从而引起潜在的控制困难。此外,在实际生产中,无论是单个换热设备还是整个网络都... 详细信息

换热器网络在化工生产过程中起着能量回收、节能降耗的重要作用。常规换热器网络综合方法以经济性为目标进行参数和结构优化,导致换热设备之间的强烈耦合从而引起潜在的控制困难。此外,在实际生产中,无论是单个换热设备还是整个网络都不可避免地受到一些不确定性因素的干扰,故能够抵御这些扰动的可控性换热器网络是至关重要的。通过考虑网络结构与可控性之间的相互作用,提出可控性换热器网络综合方法,并基于多工况优化探究了决策变量对网络结构的影响。然后以柔性指数衡量扰动存在情况下换热器网络操作可行性,进一步优化换热器网络结构以抵御不确定性因素的干扰。最后,通过算例分析验证了该方法的可行性与有效性。

关键词：系统工程换热器网络不确定性多工况过程控制优化

The dynamic evolution of aggregated lithium dendrites in lithium metal batteries

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Chinese Journal of chemical engineering 2021年第9期34卷 137-143页

作者： Xin Shen Rui zhang Shuhao Wang Xiang Chen Chuan Zhao Elena Kuzmina Elena Karaseva Vladimir Kolosnitsyn Qiang zhang Beijing Key Laboratory of Green chemical Reaction engineering and technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China school of Chemistry The University of New South WalesSydneyNSW 2052Australia Ufa Institute of Chemistry UFRC RAS Ufa450054Russia

lithium(li)metal anodes promise an ultrahigh theoretical energy density and low redox potential,thus being the critical energy material for next-generation ***,the formation of li dendrites in li metal anodes remarkably hinders the practical applications of li metal ***,the dynamic evolution of discrete li dendrites and aggregated li dendrites with increasing current densities is visualized by in-situ optical microscopy in conjunction with ex-situ scanning electron *** revealed by the phase field simulations,the formation of aggregated li dendrites under high current density is attributed to the locally concentrated electric field rather than the depletion of li *** specifically,the locally concentrated electric field stems from the spatial inhomogeneity on the li metal surface and will be further enhanced with increasing current *** the above two factors with the help of the constructed phase field model is able to regulate the electrodeposited morphology from aggregated li dendrites to discrete li dendrites,and ultimately columnar li *** methodology and mechanistic understanding established herein give a significant step toward the practical applications of li metal anodes.

关键词： Electrochemistry li dendrites Rechargeable li batteries In-situ optical microscopy Phase field model Electrochemical engineering

邻氨基芳香腈与羰基化合物的反应机理及其产物的骨架结构

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有机化学 2014年第12期34卷 2424-2437页

作者：杨俊娟史大昕刘明星张立军张奇李加荣北京理工大学化工与环境学院北京100081 天津理工大学化学化工学院天津300191

Friedlnder反应是合成具有生物活性、光电活性的喹啉衍生物的重要方法.其典型转化之一——邻氨基芳香腈与羰基化合物的Friedlnder缩合在得到经典的转化产物的同时可以得到新骨架产物,这种新转化自本课题组报道以来已受到国内外学者... 详细信息

Friedlnder反应是合成具有生物活性、光电活性的喹啉衍生物的重要方法.其典型转化之一——邻氨基芳香腈与羰基化合物的Friedlnder缩合在得到经典的转化产物的同时可以得到新骨架产物,这种新转化自本课题组报道以来已受到国内外学者的诸多关注,但该转化的新产物骨架结构尚存争议.本综述概括了该新转化自发现以来国内外的研究进展,从13C NMR,FT-IR,X射线单晶衍射数据等明确了新转化反应得到的产物骨架为喹唑啉酮结构.完整地提出了该类Friedlnder分岔反应的转化机理:经由分子内的Pinner反应到Dimroth重排的过程存在于邻氨基芳香腈和酮的经典Friedlnder反应中(PDF反应).

关键词：邻氨基芳香腈分岔转化 Friedlander转化喹唑啉酮苯并噁嗪产物结构

Glassy magnetic ground state in layered compound MnSb_(2)Te_(4)

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Science china Materials 2022年第2期65卷 477-485页

作者： Hao li Yaoxin li Yukun lian Weiwei Xie ling Chen Jinsong zhang Yang Wu Shoushan Fan school of Materials Science and engineering Tsinghua UniversityBeijing 100084China Department of Mechanical engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Department of Chemistry and chemical Biology Rutgers UniversityPiscataway 08854USA Tsinghua-Foxconn Nanotechnology Research Center Tsinghua UniversityBeijing 100084China Frontier Science Center for Quantum Information Beijing 100084China

As a sister compound of MnBi_(2)Te_(4),the highquality MnSb_(2)Te_(4) single crystals are grown via solid-state reaction where prolonged annealing and narrow temperature window play critical roles on account of its thermal ***-crystal X-ray diffraction(SCXRD)analysis on MnSb_(2)Te_(4) illustrates a crystal model that is isostructural to MnBi_(2)Te_(4),consisting of Te-Sb-Te-Mn-Te-Sb-Te septuple layers(SLs)stacking in an ABC ***,MnSb_(2)Te_(4) reveals a more pronounced cation intermixing in comparison with MnBi_(2)Te_(4),comprising 28.9(7)%Sb antisite defects on the Mn(3a)site and 19.3(6)%Mn antisite defects on the Sb(6c)site,which may give rise to novel magnetic properties in emerging layered MnBi_(2)Te_(4)-family *** the antiferromagnetic(AFM)nature in MnBi_(2)Te_(4),MnSb_(2)Te_(4) exhibits a glassy magnetic ground state below 24 K and can be easily tuned to a ferromagnetic state under a weak applied magnetic *** magnetic hysteresis,anisotropy,and relaxation process are investigated in detail via static and dynamic magnetization ***,anomalous Hall effect as a p-type conductor is demonstrated with transport *** work grants MnSb_(2)Te_(4) a possible access to the future exploration of exotic quantum physics by removing the odd/even layer number restraint in realizing quantum transport phenomena in intrinsic AFM MnBi_(2)Te_(4)-family materials,as a result of the crossover between its magnetism and potential topology arising from the Sb-Te layer.

关键词： MnSb2Te4 crystal growth glassy magnetic ground state anomalous Hall effect

基于分子动力学的氧化石墨烯拉伸断裂行为与力学性能研究

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力学学报 2019年第5期51卷 1393-1402页

作者：李东波刘秦龙张鸿驰雷蓬勃赵冬西安建筑科技大学理学院力学系西安710055 西安建筑科技大学理学院力学实验中心西安710055

与石墨烯相比,氧化石墨烯(graphene oxide, GO)的亲水性、分散性和反应活性更好,更易于作为增强材料而研发生成性能超常的复合材料,但另一方面,由于其电子结构较为复杂,致使目前有关力学方面的研究存在一定差异.本文利用分子动力学方法... 详细信息

与石墨烯相比,氧化石墨烯(graphene oxide, GO)的亲水性、分散性和反应活性更好,更易于作为增强材料而研发生成性能超常的复合材料,但另一方面,由于其电子结构较为复杂,致使目前有关力学方面的研究存在一定差异.本文利用分子动力学方法,建立了羟基、羧基和环氧基等官能团随机分布的GO原子模型;通过单向拉伸模拟,分析了其断裂行为,结果表明,远离羟基和羧基的环氧基对断裂具有'诱导'作用,并从化学成键、体系能量和应力分布三个角度对其机理进行了阐释;此外,进一步研究了拉伸应力-应变曲线、极限强度、极限应变等力学性能与含氧官能团覆盖度间的关系,结果表明,极限强度、极限应变均随含氧官能团覆盖度的增大而呈减小趋势.分析认为,主要原因是官能团的出现对石墨烯面内的sp^2杂化形式造成了破坏,进而使得原子间键合能弱化,随着含氧官能团的覆盖度的增大,被弱化的键合能的数量和程度将越大,从而使得GO的极限强度、极限应变等越低.研究结果可为GO的基础研究和工程应用提供参考.

关键词：分子动力学氧化石墨烯拉伸断裂行为力学性能

Self‑Generated Buried Submicrocavities for High‑Performance Near‑Infrared Perovskite light‑Emitting Diode

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Nano-Micro Letters 2023年第8期15卷 355-367页

作者： Jiong li Chenghao Duan Qianpeng zhang Chang Chen Qiaoyun Wen Minchao Qin Christopher C.S.Chan Shibing Zou Jianwu Wei Zuo Xiao Chuantian Zuo Xinhui Lu Kam Sing Wong Zhiyong Fan Keyou Yan school of Environment and Energy State Key Lab of Luminescent Materials and DevicesGuangdong Provincial Key Laboratory of Solid Wastes Pollution Control and RecyclingSouth China University of TechnologyGuangzhou 510000People’s Republic of China Department of Electronic and Computer engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongPeople’s Republic of China Department of Physics The Chinese University of Hong KongShatinHong KongPeople’s Republic of China Department of Physics The Hong Kong University of Science and TechnologyClear Water BayKowloon 999077Hong KongPeople’s Republic of China school of Chemistry and chemical engineering Guangxi UniversityNanning 530004People’s Republic of China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190People’s Republic of China

ABSTRACT Embedding submicrocavities is an effective approach to improve the light out-coupling efficiency(LOCE)for planar perovskite light-emitting diodes(PeLEDs).In this work,we employ phenethylammonium iodide(PEAI)to trigger the Ostwald ripening for the downward recrystallization of perovskite,resulting in spontaneous formation of buried submicrocavities as light output *** simulation suggests the buried submicrocavities can improve the LOCE from 26.8 to 36.2%for near-infrared ***,PeLED yields peak external quantum efficiency(EQE)increasing from 17.3%at current density of 114 mA cm^(−2)to 25.5%at current density of 109 mA cm^(−2)and a radiance increasing from 109 to 487 W sr^(−1)m^(−2)with low *** turn-on voltage decreased from 1.25 to 1.15 V at 0.1 W sr^(−1)m^(−2).Besides,downward recrystallization process slightly reduces the trap density from 8.90×10^(15)to 7.27×10^(15)cm^(−3).This work provides a self-assembly method to integrate buried output coupler for boosting the performance of PeLEDs.

关键词： Perovskite light-emitting diodes Downward recrystallization Buried submicrocavities light out-coupling efficiency Radiative recombination

Theoretical Study of Hydrogen-Bond Interactions of CO_(2) in Organic Absorbent 1,3-Diphenylguanidine

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Chinese Journal of chemical Physics 2022年第3期35卷 471-480,I0002页

作者： Yiqiu Wang Han Gao Yajing li Igor Ying zhang Fei Xia school of Chemistry and Molecular engineering NYU-ECNU Center for Computational Chemistry at NYU ShanghaiEast China Normal UniversityShanghai 200062China Collaborative Innovation Center of Chemistry for Energy Materials ShanghaiKey Laboratory of Molecular Catalysis and Innovative MaterialsMOE Key Laboratory of Computational Physical SciencesDepartments of ChemistryFudan UniversityShanghai 200433China

Carbon capture and storage technology have been rapidly developed to reduce the carbon dioxide(CO2)emission into the *** has been found that the amine-based organic molecules could absorb CO_(2) efficiently and form the bicarbonate salts through hydrogen-bond(H-bond)***,the aqueous 1,3-diphenylguanidine(DPG)solution was developed to trap and convert CO_(2) to valuable chemicals under ambient ***,how the DPG molecules interact with CO_(2) in an aqueous solution remains *** this work,we perform molecular dynamics simulations to explore the atomistic details of CO_(2) in the aqueous *** simulated results reveal that the protonated DPGH+and the bicarbonate anions prefer to form complexes through different H-bond *** double H-bonds are quite stable in thermodynamics,as indicated from the accurate density functional theory *** study is helpful to understand the catalytic mechanism of CO_(2) conversion in the aqueous DPG.

关键词： CO2 conversion Molecular dynamics simulation Density functional theory calculation Double H-bond 1,3-diphenylguanidine

Study of structure-property relationship of semiconductor nanomaterials by off-axis electron holography

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Journal of Semiconductors 2022年第4期43卷 36-45页

作者： Luying li Yongfa Cheng Zunyu liu Shuwen Yan li li Jianbo Wang Lei zhang Yihua Gao Center for Nanoscale Characterization&Devices Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China school of Physics and technology Center for Electron MicroscopyMOE Key Laboratory of Artificial Micro-and Nano-Structuresand the Institute for Advanced StudiesWuhan UniversityWuhan 430072China Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei Collaborative Innovation Center for Advanced Organic Chemical MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China

As the scaling down of semiconductor devices, it would be necessary to discover the structure-property relationship of semiconductor nanomaterials at nanometer scale. In this review, the quantitative characterization technique off-axis electron holography is introduced in details, followed by its applications in various semiconductor nanomaterials including group IV, compound and two-dimensional semiconductor nanostructures in static states as well as under various stimuli. The advantages and disadvantages of off-axis electron holography in material analysis are discussed, the challenges facing in-situ electron holographic study of semiconductor devices at working conditions are presented, and all the possible influencing factors need to be considered to achieve the final goal of fulfilling quantitative characterization of the structure-property relationship of semiconductor devices at their working conditions.

关键词： semiconductor nanostructure structure-property relationship off-axis electron holography electrostatic potential charge distribution