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High sulfur-doped hard carbon anode from polystyrene with enhanced capacity and stability for potassium-ion storage

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Journal of Energy Chemistry 2022年第5期31卷 688-698页

作者： Xiaoyan Chen Xin-Bing Cheng Zhigang Liu Advanced Catalytic Engineering Research Center of the Ministry of Education College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082HunanChina Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Carbonaceous materials are regarded as a promising anode material for potassium ion batteries(PIBs)due to their high electronic conductivity, abundant resources and low cost. However, relatively low storage capacity and structural instability still hinder their practical application. Herein, high sulfur-doped hard carbon(SHC-3) with a sulfur up to 27.05 at% is synthesized from polystyrene and sulfur as precursors. As an anode for PIBs, the SHC-3 delivers a superb cycling stability and rate performance(298.1 mAh g^(-1)at 100 mA g^(-1) for 1000 cycles, a capacity retention of 95.2%;220.2 mAh g^(-1)at 500 mA g^(-1) after 5200 cycles). The potassium storage of SHC-3 exhibits excellent cyclic stability at both low and high rates.Structure and kinetic studies demonstrate that the larger interlayer spacing(0.382 nm) of the SHC-3 accelerates the diffusion of potassium ions and effectively alleviates the volume expansion, and thus maintains the structure stability during the process of potassization/de-potassization. Meanwhile, the density functional theory calculation shows that the doped sulfur atoms provide abundant active sites for the adsorption of potassium ions, thereby increasing the reversible capacity of PIBs. This work provides a new scheme for the design of carbonaceous anode materials with high capacity and long cycle life.

关键词： Hard carbon materials Sulfur doping Anode Potassium-ion storage DFT calculation

A Multi-mode Electronic Load Sensing Control Scheme with Power Limitation and Pressure Cut-off for Mobile Machinery

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 157-170页

作者： Min cheng Bolin Sun Ruqi Ding bing Xu State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing400044China Key Laboratory of Conveyance and Equipment Ministry of EducationEast China Jiaotong UniversityNanchang330052China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310027China

In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are integrated into the electronic controller only from the pump level,leading to the potential instability of the overall system.To solve this problem,a multi-mode electrohydraulic load sensing(MELS)control scheme is proposed especially considering the switching stability from the system level,which includes four working modes of flow control,load sensing,power limitation,and pressure control.Depending on the actual working requirements,the switching rules for the different modes and the switching direction(i.e.,the modes can be switched bilaterally or unilaterally)are defined.The priority of different modes is also defined,from high to low:pressure control,power limitation,load sensing,and flow control.When multiple switching rules are satisfied at the same time,the system switches to the control mode with the highest priority.In addition,the switching stability between flow control and pressure control modes is analyzed,and the controller parameters that guarantee the switching stability are obtained.A comparative study is carried out based on a test rig with a 2-ton hydraulic excavator.The results show that the MELS controller can achieve the control functions of proper flow supplement,power limitation,and pressure cut-off,which has good stability performance when switching between different control modes.This research proposes the MELS control method that realizes the stability of multi-mode switching of the hydraulic system of mobile machinery under different working conditions.

关键词： Hydraulic control Load sensing Multi-Mode Power limitation Mobile machinery

Compliance motion control of the hydraulic dual-arm manipulator with adaptive mass estimation of unknown object

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Frontiers of Mechanical Engineering 2024年第1期19卷 35-52页

作者： Bolin SUN Min cheng Ruqi DING bing XU State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China Key Laboratory of Conveyance and Equipment(Ministry of Education) East China Jiaotong UniversityNanchang 330013China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Given the limited operating ability of a single robotic arm,dual-arm collaborative operations have become increasingly prominent.Compared with the electrically driven dual-arm manipulator,due to the unknown heavy load,difficulty in measuring contact forces,and control complexity during the closed-chain object transportation task,the hydraulic dual-arm manipulator(HDM)faces more difficulty in accurately tracking the desired motion trajectory,which may cause object deformation or even breakage.To overcome this problem,a compliance motion control method is proposed in this paper for the HDM.The mass parameter of the unknown object is obtained by using an adaptive method based on velocity error.Due to the difficulty in obtaining the actual internal force of the object,the pressure signal from the pressure sensor of the hydraulic system is used to estimate the contact force at the end-effector(EE)of two hydraulic manipulators(HMs).Further,the estimated contact force is used to calculate the actual internal force on the object.Then,a compliance motion controller is designed for HDM closed-chain collaboration.The position and internal force errors of the object are reduced by the feedback of the position,velocity,and internal force errors of the object to achieve the effect of the compliance motion of the HDM,i.e.,to reduce the motion error and internal force of the object.The required velocity and force at the EE of the two HMs,including the position and internal force errors of the object,are inputted into separate position controllers.In addition,the position controllers of the two individual HMs are designed to enable precise motion control by using the virtual decomposition control method.Finally,comparative experiments are carried out on a hydraulic dual-arm test bench.The proposed method is validated by the experimental results,which demonstrate improved object position accuracy and reduced internal force.

关键词： hydraulic dual-arm manipulator compliance motion control unknown object adaptive mass estimation nonlinear control

Motion control of multi-actuator hydraulic systems for mobile machineries： Recent advancements and future trends

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Frontiers of Mechanical Engineering 2018年第2期13卷 151-166页

作者： bing XU Min cheng The State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Hangzhou 310027 China The State Key Laboratory of Mechanical Transmissions School of Mechanical Engineering Chongqing University Chongqing 400044 China

This paper presents a survey of recent advancements and upcoming trends in motion control technologies employed in designing multi-actuator hydraulic systems for mobile machineries. Hydraulic systems have been extensively used in mobile machineries due to their superior power density and robustness. However, motion control technologies of multi-actuator hydraulic systems have faced increasing challenges due to stringent emission regulations. In this study, an overview of the evolution of existing throttling control technologies is presented, including open-center and load sensing controls. Recent advancements in energy-saving hydraulic technologies, such as individual metering, displacement, and hybrid controls, are briefly summarized. The impact of energy-saving hydraulic technologies on dynamic perfor- mance and control solutions are also discussed. Then, the advanced operation methods of multi-actuator mobile machineries are reviewed, including coordinated and haptic controls. Finally, challenges and opportunities of advanced motion control technologies are presented by providing an overall consideration of energy efficiency, controllability, cost, reliability, and other aspects.

关键词： motion control electrohydraulic control energy efficiency mobile machineries

Reflection-based traveltime and waveform inversion with second-order optimization

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Petroleum Science 2022年第4期19卷 1582-1591页

作者： Teng-Fei Wang Jiu-Bing Cheng Jian-Hua Geng State Key Laboratory of Marine Geology Tongji UniversityShanghai200092China School of Ocean and Earth Science Tongji UniversityShanghai200092China

Reflection-based inversion that aims to reconstruct the low-to-intermediate wavenumbers of the subsurface model, can be a complementary to refraction-data-driven full-waveform inversion(FWI), especially for the deep target area where diving waves cannot be acquired at the surface. Nevertheless, as a typical nonlinear inverse problem, reflection waveform inversion may easily suffer from the cycleskipping issue and have a slow convergence rate, if gradient-based first-order optimization methods are used. To improve the accuracy and convergence rate, we introduce the Hessian operator into reflection traveltime inversion(RTI) and reflection waveform inversion(RWI) in the framework of second-order optimization. A practical two-stage workflow is proposed to build the velocity model, in which Gauss-Newton RTI is first applied to mitigate the cycle-skipping problem and then Gauss-Newton RWI is employed to enhance the model resolution. To make the Gauss-Newton iterations more efficiently and robustly for large-scale applications, we introduce proper preconditioning for the Hessian matrix and design appropriate strategies to reduce the computational costs. The example of a real dataset from East China Sea demonstrates that the cascaded Hessian-based RTI and RWI have good potential to improve velocity model building and seismic imaging, especially for the deep targets.

关键词： Reflection waveform inversion Reflection traveltime inversion Gauss-Newton Hessian

Differential Operator Approach to■quantum Groups and Their Oscillator Representations

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1360-1374页

作者： Zhao bing FAN Ji cheng GENG Shao Long HAN College of Mathematical Science Harbin Engineering UniversityHarbin 150001P.R.China

For a quasi-split Satake diagram,we define a modified q-Weyl algebra,and show that there is an algebra homomorphism between it and the corresponding■quantum group.In other words,we provide a differential operator approach to■quantum groups.Meanwhile,the oscillator representations of■quantum groups are obtained.The crystal basis of the irreducible subrepresentations of these oscillator representations are constructed.

关键词： ■quantum group differential operator oscillator representation crystal basis

Effects of fresh-cut and storage on glucosinolates profile using broccoli as a case study

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Horticultural Plant Journal 2023年第2期9卷 285-292页

作者： Xiaoxin Huang Bing Cheng Yaqin Wang Guangmin Liu Liping Hu Xiaolu Yu Hongju He Institute of Agri-food Processing and Nutrition Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Beijing Vegetable Research Center Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 100029China

Glucosinolates(GLS) contribute to the unique flavour, nutrition, and plant defence of the Cruciferous vegetables. Understanding the GLS changes through postharvest processing is essential for defined preservation. In this study, four different fresh-cut types, whole flower(W),floret(F), quarterly cut floret(QF) and shredded floret(FS) of broccoli, were stored for 0, 1, 2 and 3 day(s) to explore GLS responses to postharvest treatments. As a result, seven GLS were identified, mainly including glucoraphanin(RAA), neoglucobrassicin(NEO), and glucobrassicin(GBC)and accounting for 52.69%, 20.12% and 14.99% of the total GLS(21.92 ± 0.48) μmol · g ^(-1 )DW, respectively. FS had the sharpest decrease in GLS after three days of storage(6.55 ± 0.37) μmol · g-1DW, while QF had the least(10.16 ± 0.33) μmol · g ^(-1 )DW. All GLS components decreased over storage, except for 4-methoxyglucobrassicin(4 ME) in FS and QF, suggesting its key role in serious wound defence. The results suggested certain postharvest approaches influenced the flavour and nutrition of broccoli.

关键词： Cruciferous vegetables Broccoli Glucosinolate Wound stress Storage Fresh-cut

Strategies that regulate LSD1 for novel therapeutics

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1494-1507页

作者： Meng Li Mengge Dai Bing Cheng Shaotong Li Enhui Guo Junwei Fu Ting Ma Bin Yu School of Pharmaceutical Sciences&Key Laboratory of Advanced Drug Preparation Technologies Ministry of EducationZhengzhou UniversityZhengzhou 450001China College of Chemistry Zhengzhou UniversityZhengzhou 450001China Tianjian Laboratory of Advanced Biomedical Sciences Institute of Advanced Biomedical SciencesZhengzhou UniversityZhengzhou 450000China Pingyuan Laboratory State Key Laboratory of Antiviral DrugsHenan Normal UniversityXinxiang 453007China State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing 210023China

Histone methylation plays crucial roles in regulating chromatin structure and gene transcrip-tion in epigenetic modifications.Lysine-specific demethylase 1(LSD1),the first identified histone de-methylase,is universally overexpressed in various diseases.LSD1 dysregulation is closely associated with cancer,viral infections,and neurodegenerative diseases,etc.,making it a promising therapeutic target.Several LSD1 inhibitors and two small-molecule degraders(UM171 and BEA-17)have entered the clinical stage.LSD1 can remove methyl groups from histone 3 at lysine 4 or lysine 9(H3K4 or H3K9),resulting in either transcription repression or activation.While the roles of LSD1 in transcrip-tional regulation are well-established,studies have revealed that LSDl can also be dynamically regulated by other factors.For example,the expression or activity of LSD1 can be regulated by many proteins that form transcriptional corepressor complexes with LSD1.Moreover,some post-transcriptional modifica-tions and cellular metabolites can also regulate LSD1 expression or its demethylase activity.Therefore,in this review,we will systematically summarize how proteins involved in the transcriptional corepressor complex,various post-translational modifications,and metabolites act as regulatory factors for LSD1 ac-tivity.

关键词： LSD1 regulation Transcription repression Transcription activation the Corepressor complex Post-transcriptional modifications Metabolites

Engineering d-band center of nickel in nickel@nitrogen-doped carbon nanotubes array for electrochemical reduction of CO_(2)to CO and Zn-CO_(2)batteries

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Chinese Chemical Letters 2022年第8期33卷 3721-3725页

作者： Shujin Shen cheng Han bing Wang Yingde Wang Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Self-supported transition-metal single-atom catalysts(SACs)facilitate the industrialization of electrochemical CO_(2) reduction,but suffer from high structural heterogeneity with limited catalytic selectivity.Here we present a facile and scalable approach for the synthesis of self-supported nickel@nitrogen-doped carbon nanotubes grown on carbon nanofiber membrane(Ni@NCNTs/CFM),where the Ni single atoms and nanoparticles(NPs)are anchored on the wall and inside of nitrogen-doped carbon nanotubes,respectively.The side effect of Ni NPs was further effectively inhibited by alloying Ni with Cu atoms to alter their d-band center,which is theoretically predicted and experimentally proved.The optimal catalyst Ni_(9)Cu_(1)@NCNTs/CFM exhibits an ultrahigh CO Faradic efficiency over 97%at-0.7 V versus reversible hydrogen electrode.Additionally,this catalyst shows excellent mechanical strength which can be directly used as a self-supporting catalyst for Zn-CO_(2) battery with a peak power density of~0.65 mW/cm^(2)at2.25 mA/cm^(2) and a long-term stability for 150 cycles.This work opens up a general avenue to facilely prepare self-supported SACs with unitary single-atom site for CO_(2) utilization.

关键词： CO_(2)reduction Electrocatalysis Self-supported catalysts Single atom Zn-CO_(2)battery