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Chinese Journal of Chemistry 2016年第12期34卷 1297-1303页

作者： Yulong Gao Tao Wang fengyu liu State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian Liaoning 116024 China School of Chemistry Dalian University of Technology Dalian Liaoning 116024 China

The electrochemiluminescence （ECL） of the Ru（phen）3^2＋/thymine （T） system at bare and graphene oxide （GO）-modified glassy carbon （GC） electrodes was utilized to determine Hg2＋ in tap water. The ECL intensity of Ru（phen）3^2＋ was considerably enhanced by the addition of thymine because of the occurrence of ECL tion between them. Subsequently, the ECL intensity of Ru（phen）3^2＋/T system rapidly decreased with the addition of Ru（phen）3^2＋ because of the formation ofa T-Hg^2＋-T complex. A linear response （R2=0.9914） was obtained over a Hg^2＋ concentration range of 1.0×10 9 mol/L to 1.0×10^-5 mol/L with a detection limit of 3.4×10^-10 mol/L at a bare GC electrode in 0.1 mol/L phosphate buffer （pH=8.0）. The detection limit can be further reduced to 4.2 ×10^-12 mol/L after modification of the GC electrode by GO. To verify its applicability, the proposed method was utilized to determine Hg^2＋ in tap water and simulated wastewater. The method exhibited good reproducibility and stability and thus reveals the possibility of developing a novel ECL detection method for Hg^2＋.

关键词： electrochemiluminescence (ECL) determination 2+ Hg thymine graphene oxide

Recent Progress of Magnetically Actuated DNA Micro/Nanorobots

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Cyborg and Bionic Systems 2022年第1期2022卷 43-54页

作者： fengyu liu Xiaoming liu Qiang Huang Tatsuo Arai Key Labraoryof Bmetic Robts and Sym Minsry of EduationState KeyLaboratoryofInteligent Controlandcisnof Complex SystemBejing Advanced Innovation Center for Intlligent Robots and Systems and School of Mechatron ical Engineering Bejing Institute of TechnologyBeijing 100081China Center for Neuroscience and Biomedical Enginring The University of Eletro-CommunicationsTokyo 182-8585 Japan

In the past few decades,the field of DNA origami based micro/nanotechnology has developed dramatically and spawned attention increasingly,as its high integrality,rigid structure,and excellent resistance ability to enzyme *** two-dimensional and three-dimensional DNA nanostructures coordinated with optical,chemical,or magnetic triggers have been designed and assembled,extensively used as versatile templates for molecular robots,nanosensors,and intracellular drug *** magnetic field has been widely regarded as an ideal driving and operating system for micro/nanomaterials,as it does not require high intensity lasers like light control,nor does it need to change the chemical composition similar to chemical ***,we review the recent achievements in the induction and actuation of DNA origami-based nanodevices that respond to magnetic *** magnetic actuation-based DNA nanodevices were regularly combined with magnetic beads or gold nanopartides and applied to generate single stranded scaffolds,assemble various DNA nanostructures,and purify specific DNA ***,they also produced artificial magnetism or moved regularly driven by *** fields to explain deeper scientific issues.

关键词： resistance magnetic versatile

Stability Analysis of a Force-Aided Lever Actuation System for Dry Clutches with Negative Stiffness Element

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Journal of Shanghai Jiaotong university(Science) 2018年第2期23卷 218-226页

作者： liu fengyu a b c CHEN Li a a.State Key Laboratory of Ocean Engineerin b. Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploratio c. National Laboratory of Automotive Electronics and Control Shanghai Jiao Tong University Shanghai 200240 China

A force-aided lever with a preload spring is not only force-saving but also energy-saving. Therefore, it has great potential to be applied to dry clutch actuations. However, the negative stiffness of the clutch diaphragm spring introduces unstable dynamics which becomes more intensive due to the preload spring. In order to explore the intensified unstability, this paper builds dynamic models for the rotating lever coupling a negative stiffness diaphragm spring and a preload spring. The stability analysis using the Routh-Huiwitz criterion shows that the open-loop system can never be stable due to the negative stiffness. Even if the diaphragm spring stiffness is positive, the system is still unstable when the preload of the spring exceeds an upper limit. A proportionalintegral-derivative(PID) closed-loop scheme addressing this problem is designed to stabilize the system. The stability analysis for the closed-loop system shows that stable region emerges in spite of the negative stiffness; the more the negative stiffness is, the less the allowed preload is. Further, the influences of the dimensions and PID parameters on the stability condition are investigated. Finally, the transient dynamic responses of the system subjected to disturbance are compared between the unstable open-loop and stabilized closed-loop systems.

关键词： negative stiffness preload spring stability dry clutch actuation system force-aided lever

Manual Transmission Gear Rattle Vibration Research Based on Mathematical and Multi-Body Dynamics Co-simulation and Experiment

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Journal of Shanghai Jiaotong university(Science) 2019年第4期24卷 524-533页

作者： LI Meng ZHANG Yong liu fengyu YIN Chengliang National Engineering Laboratory for Automotive Electronic Control Technology Shanghai Jiao Tong UniversityShanghai 200240China

A method, which compares the angular acceleration and vibration spectrums of shafts and gears with physical characteristics of gearbox as tooth numbers and speed ratios, is proposed to find the source of gear rattle vibration. A mathematical and multi-body dynamics co-simulation model is built to reproduce the gear rattle phenomenon of one typical type of manual transmission. In the model, multi-body dynamics part is used for rotational motion and engagement simulation of gearbox shafts and gears, while mathematical part for control and data processing. The simulation results show that the sound source of the gear rattle from the first gear to the third gear is similar to the experimental results;different parameters like rotating damping, contact stiffness,contact damping, inertia moment and torque fluctuation making effects on gear rattle vibration strength are researched and simulated. The comparison of the simulation and experimental results shows that this method can provide recommendations for solving practical gear rattle problems.

关键词： gear rattle manual transmission mathematical model multi-body dynamics co-simulation

Naphthalimide-rhodamine based fluorescent probe for ratiometric sensing of cellular pH

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Chinese Chemical Letters 2017年第10期28卷 2005-2008页

作者： Jia Wen Pengyi Xia Ziming Zheng Yongqian Xu Hongjuan Li fengyu liu Shiguo Sun Shaanxi Key Laboratory of Natural Products & Chemical Biology College of Chemistry & Pharmacy Northwest A&F University State Key Laboratory of Fine Chemicals School of Chemistry Dalian University of Technology

The pH values of lysosomes in cancer cells is slightly lower than that in normal cells, which can be used to distinguish cancer cells from normal cells. According to this, a naphthalimide-rhodamine based fluorescent probe（hereafter referred to as RBN） with a pK_a of 4.20 was designed and synthesized for ratiometric sensing of cellular pH via fluorescence resonance energy transfer（FRET）, which can respond to different pH precisely through ratiometric fluorescence intensity（Ⅰ_（577）/Ⅰ_（540））. RBN can be employed to distinguish cancer cells from normal cells on the basis of different fluorescent response, in particular, RBN showed excellent water solubility and low cell toxicity, all these are quite significant for potential application in cancer diagnose and therapy.

关键词： Naphthalimide-rhodamine derivative Cellular pH Ratiometric detection Imaging Fluorescence resonance energy transfer(FRET)

Pathology of pain and its implications for therapeutic interventions

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2851-2899页

作者： Bo Cao Qixuan Xu Yajiao Shi Ruiyang Zhao Hanghang Li Jie Zheng fengyu liu You Wan Bo Wei Department of General Surgery First Medical CenterChinese PLA General HospitalBeijing 100853China Medical School of Chinese PLA Beijing 100853China Neuroscience Research Institute and Department of Neurobiology School of Basic Medical SciencesKey Laboratory for NeuroscienceMinistry of Education/National Health CommissionPeking UniversityBeijing 100191China

Pain is estimated to affect more than 20%of the global population,imposing incalculable health and economic *** pain management is crucial for individuals suffering from ***,the current methods for pain assessment and treatment fall short of clinical *** from advances in neuroscience and biotechnology,the neuronal circuits and molecular mechanisms critically involved in pain modulation have been *** research achievements have incited progress in identifying new diagnostic and therapeutic *** this review,we first introduce fundamental knowledge about pain,setting the stage for the subsequent *** review next delves into the molecular mechanisms underlying pain disorders,including gene mutation,epigenetic modification,posttranslational modification,inflammasome,signaling pathways and *** better present a comprehensive view of pain research,two prominent issues,sexual dimorphism and pain comorbidities,are discussed in detail based on current *** status quo of pain evaluation and manipulation is summarized.A series of improved and innovative pain management strategies,such as gene therapy,monoclonal antibody,brain-computer interface and microbial intervention,are making strides towards clinical *** highlight existing limitations and future directions for enhancing the quality of preclinical and clinical *** to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice,thereby improving pain management from bench to bedside.

关键词： pain thereby summarized

PeerIDS - A Distributed Network Intrusion Detection System Based on the Peer-to-Peer Model

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通讯和计算机（中英文版） 2006年第5期3卷 66-74页

作者： Shu Jin fengyu liu Manwu Xu Department of Computer Science Nanjing University of Science and Technology Nanjing 210094 China State Key Software Laboratory Nanjing University Nanjing 210093 China

Web Classification Based on Latent Semantic Indexing

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通讯和计算机（中英文版） 2006年第1期3卷 24-27页

作者： Qianmu Li Manwu Xu Jun Hou fengyu liu State Key Lab of Computer Software and New Technology Nanjing University Nanjing 210093 China Department of Computer Science and Technology Nanjing University of Science and Technology Nanjing 210094 China

成核剂和扩链剂对PLA/PBAT共混体系性能的影响

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工程塑料应用 2023年第10期51卷 154-159,166页

作者：刘凤玉山西省化工研究所(有限公司) 太原030006

为改善聚乳酸(PLA)/聚己二酸-对苯二甲酸丁二酯(PBAT)共混体系相容性以及提高共混体系的应用性能,将扩链剂苯乙烯-甲基丙烯酸甲酯-甲基丙烯酸缩水甘油酯共聚物(KL-E4370)和成核剂癸二酸二苯基二酰肼(TMC-300)通过熔融共混添加到PLA/PBA... 详细信息

为改善聚乳酸(PLA)/聚己二酸-对苯二甲酸丁二酯(PBAT)共混体系相容性以及提高共混体系的应用性能,将扩链剂苯乙烯-甲基丙烯酸甲酯-甲基丙烯酸缩水甘油酯共聚物(KL-E4370)和成核剂癸二酸二苯基二酰肼(TMC-300)通过熔融共混添加到PLA/PBAT共混物中,制备了PLA/PBAT/KL-E/TMC共混体系。采用傅里叶变换红外光谱仪对扩链剂KL-E4370和成核剂TMC-300进行表征;采用扫描电子显微镜研究扩链剂KL-E4370和成核剂TMC-300的添加对PLA/PBAT共混体系微观结构的影响;通过热重分析仪、差式扫描量热仪和拉力试验机研究了扩链剂KLE4370和成核剂TMC-300对PLA/PBAT共混体系热稳定性、结晶性能以及拉伸性能等的影响。结果表明,扩链剂KLE4370的加入改善了PLA与PBAT基体之间的相容性,PLA/PBAT共混体系界面的孔洞和裂纹明显减少,应力传递效率提高,拉伸强度上升,从未加扩链剂的42.7 MPa提高到47.6 MPa,扩链剂KL-E4370对PLA/PBAT共混体系的热稳定性影响不大;当同时加入扩链剂KL-E4370和成核剂TMC-300后,PLA/PBAT/KL-E/TMC的结晶性能得到明显的改善,与PLA/PBAT相比,冷结晶现象几乎完全消失,结晶温度提高了31.50℃,结晶度提高了3倍多。

关键词：聚乳酸聚己二酸-对苯二甲酸丁二酯结晶性能扩链剂成核剂

基于深度学习与特征点速度约束的室内动态SLAM方法

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中国惯性技术学报 2023年第5期31卷 438-443页

作者：刘丰宇程向红曹毅微惯性仪表与先进导航技术教育部重点实验室南京210096 东南大学仪器科学与工程学院南京210096

针对动态环境下同时定位与建图(SLAM)算法定位信息不准确、建图偏移严重的问题,提出一种深度学习与特征点速度约束相结合的室内动态SLAM方法。引入基于深度学习的潜在动态目标检测线程与基于ORB-LK光流金字塔的特征点速度计算线程。首先... 详细信息

针对动态环境下同时定位与建图(SLAM)算法定位信息不准确、建图偏移严重的问题,提出一种深度学习与特征点速度约束相结合的室内动态SLAM方法。引入基于深度学习的潜在动态目标检测线程与基于ORB-LK光流金字塔的特征点速度计算线程。首先,通过YOLO_v5算法对场景中潜在的动态目标进行识别判断,提供先验信息;然后,利用ORB-LK光流金字塔算法计算图像中特征点的相对速度,根据特征点速度约束判断潜在动态目标区域的真实动态性,更加合理地剔除动态特征点,提高视觉SLAM系统在室内动态环境下的定位精度和鲁棒性。实验结果表明,在TUM数据集中动态子序列下与ORB-SLAM2、Detect-SLAM、DS-SLAM相比,绝对轨迹均方根误差分别平均减少94.74%、51.95%、43.61%。

关键词：动态环境视觉SLAM 深度学习光流金字塔特征点速度约束