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酯化反应-气相色谱-质谱联用法测定茶叶中氯酞酸残留

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现代食品 2024年第3期30卷 178-181,185页

作者：巫立健南平市食品药品检验检测中心福建南平353000

基于芳香基羧酸与卤代烃的酯化反应,建立茶叶中氯酞酸残留的气相色谱-串联质谱分析方法。茶叶样品经乙腈提取,提取液碘乙烷衍生化、QuEChERS法净化后,滤液氮吹至近干,用乙酸乙酯定容后用气相色谱-串联质谱法测定,外标法定量。结果表明,... 详细信息

基于芳香基羧酸与卤代烃的酯化反应,建立茶叶中氯酞酸残留的气相色谱-串联质谱分析方法。茶叶样品经乙腈提取,提取液碘乙烷衍生化、QuEChERS法净化后,滤液氮吹至近干,用乙酸乙酯定容后用气相色谱-串联质谱法测定,外标法定量。结果表明,氯酞酸在5.0~50.0 ng·mL-1范围内质量浓度与其峰面积呈现良好的线性关系,相关系数均大于0.999。方法检出限为0.00005 mg·kg^(-1),定量限为0.00015 mg·kg^(-1)。在0.01 mg·kg^(-1)、0.05 mg·kg^(-1)、0.10 mg·kg^(-1)添加水平下,平均回收率为75.3%~90.2%,相对标准偏差为2.5%~8.7%。该方法简单、回收率高、重复性好,可应用于茶叶中的氯酞酸残留量的检测。

关键词：氯酞酸碘乙烷酯化反应衍生化气相色谱-串联质谱

超声波联合动态关节松动术在肱骨外上髁炎患者中的应用效果

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中国当代医药 2024年第17期31卷 65-69页

作者：吴理剑林汉燕福建医科大学附属泉州第一医院康复医学科福建泉州362000 福建医科大学附属泉州第一医院心肺康复专科福建泉州362000

目的观察超声波联合动态关节松动术治疗肱骨外上髁炎的疗效,并与单纯超声波治疗进行对比。方法选取2021年3月至2023年3月在泉州市第一医院骨科和康复医学科门诊收治的诊断为肱骨外上髁炎的患者50例作为研究对象,采用随机数字表法将其分... 详细信息

目的观察超声波联合动态关节松动术治疗肱骨外上髁炎的疗效,并与单纯超声波治疗进行对比。方法选取2021年3月至2023年3月在泉州市第一医院骨科和康复医学科门诊收治的诊断为肱骨外上髁炎的患者50例作为研究对象,采用随机数字表法将其分为对照组(n=25)和治疗组(n=25)。对照组采用常规超声波治疗,治疗组在对照组的基础上联合动态关节松动术干预。两组均持续治疗2周。比较两组患者的疼痛视觉模拟评分(VAS)、无痛握力测试(PFG)和网球肘自我评分表(PRTEE)情况。结果治疗前,两组患者的VAS评分、PRTEE评分和PFG值比较,差异无统计学意义(P>0.05)。治疗后,治疗组患者的VAS评分和PRTEE评分均低于对照组,差异有统计学意义(P<0.05)。治疗组患者治疗后的PFG值高于对照组,差异有统计学意义(P<0.05)。治疗后,两组患者的VAS评分和PRTEE评分均低于本组治疗前,PFG值均高于本组治疗前,差异有统计学意义(P<0.05)。结论单独使用超声波或超声波联合动态关节松动术治疗肱骨外上髁炎都能改善患者的VAS评分、PRTEE评分和PFG值,但超声波联合动态关节松动术的疗效明显优于单独超声波治疗,适合临床推广使用。

关键词：肱骨外上髁炎超声波动态关节松动术无痛握力

Relative roll control of satellite docking using electromagnetic coils

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Chinese Journal of Aeronautics 2023年第12期36卷 361-374页

作者： lijian wu Guangzheng RUAN Runqi HAN Bo WANG Yaobing WANG College of Electrical Engineering Zhejiang UniversityHangzhou 310012China Beijing Institute of Spacecraft System Engineering Beijing 100094China

An electromagnetic coil topology and its control strategy,which can be incorporated into the electromagnetic docking device,have been proposed for the relative roll control of two satellites in *** target satellite and the chaser satellite are respectively embarked with four and six coils evenly arranged around the docking *** the coils on the target satellite are Direct Current(DC)energized,while the currents in the coils of the chaser satellite are regulated to achieve the relative roll *** electromagnetic force/torque model is built by utilizing the frequentlyused far field *** on the fundamental components extracted from that model,this paper proposes a real-time magnetic moment vector distribution formula that simply generates a constant roll *** paper not only presents an equation for calculating the relative roll angle through the Euler angles of two satellites,but also an equation that converts the roll torque setpoint to the setpoints of the coil currents.A 3-closed-loop positioning controller composed of angle,angular velocity,and current loop is *** proposed topology is verified by finite element simulation,and the control strategy is validated by dynamics simulation and ground-based tests.

关键词： Coil array Electromagnetic docking Electromagnets Far field model Force/torque model Relative roll control

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汽车维修喷涂机器人专利标准融合路径研究

质量与认证 2024年第4期 63-65页

作者：吴礼剑晏建波廖庆财中铭谷智能机器人(广东)有限公司广东腐蚀科学与技术创新研究院东莞市质量发展标准化研究院

随着工业自动化和智能制造的快速发展,喷涂机器人在汽车维修领域得到了广泛应用。本文分析了汽车维修喷涂机器人行业现状以及该行业的专利与标准的发展现状,得出了汽车维修喷涂机器人未来的技术发展方向和标准制定方向,并搭建了围绕专... 详细信息

随着工业自动化和智能制造的快速发展,喷涂机器人在汽车维修领域得到了广泛应用。本文分析了汽车维修喷涂机器人行业现状以及该行业的专利与标准的发展现状,得出了汽车维修喷涂机器人未来的技术发展方向和标准制定方向,并搭建了围绕专利标准融合团队、专利技术转化为标准、标准实施与评价、开展专利标准融合试点和搭建专利标准融合信息平台等5个维度的汽车维修喷涂机器人专利标准融合路径,旨在为汽车维修喷涂机器人领域和其他领域专利标准融合创新发展提供参考。

关键词：汽车喷涂机器人专利标准融合路径

Optimal Designs of Wound Field Switched Flux Machines with Different DC Windings Configurations

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CES Transactions on Electrical Machines and Systems 2022年第4期6卷 359-367页

作者： Wenting Wang Yuankui Wang Enlin Ma lijian wu IEEE Zhejiang University Hangzhou3100005 China China State Shipbuilding Corporation Ltd.

Wound field switched flux(WFSF)machines exhibits characteristics of the simple robust rotor,flexible flux-adjustable capability,and no risk of ***,they suffer from a poor torque density compared with permanent magnet machines due to the ***,in this paper,two WFSF machines with single-and double-layer DC windings,respectively,are optimized for the maximum *** end-winding(EW)lengths differ in these two machines,which can affect the optimal *** parameters including the DC to armature winding copper loss ratio,slot area ratio and split ratio are optimized when two machines have the same copper loss and overall *** addition,the influence of the flux density ratio,total copper loss,air-gap length and aspect ratio on the optimal split ratio is investigated using the finite element method and results are explained through the analytical model accounting for the *** is discovered that the EWs have no effect on the optimal copper loss ratio,which is *** terms of the slot area ratio,the machine with single-layer DC windings prefers smaller DC slot areas than armature slot *** the WFSF machine with longer EWs,the optimal split ratio becomes ***,compared with other parameters,the flux density ratio can significantly affect the optimal split ratio.

关键词： Design End-winding Optimization Split ratio Wound field switched flux machine

An Enhanced Sensorless Control Scheme for PMSM Drives Considering Self-inductance Asymmetry

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CES Transactions on Electrical Machines and Systems 2022年第4期6卷 384-392页

作者： lijian wu Zekai Lyu Zekai Chen Jiaming Liu Ying Lu IEEE the College of Electrical Engineering Zhejiang UniversityHangzhou310027China Shanghai Electric Wind Power Group Company Ltd.Hangzhou310063China the 21st Research Institute of China Electronics Technology Group Corporation Ltd.Shanghai200030China

Inductance asymmetry,which is brought by inherent asymmetric parameters,manufacture tolerance,winding fault,cables with unequal lengths,etc.,of permanent-magnet synchronous machines(PMSMs)can cause current harmonics and inaccurate position *** paper proposes an enhanced fundamental model based sensorless control strategy for PMSMs with asymmetric *** proportional-integral-resonant current regulator is introduced to reduce the second-order harmonics of currents,but there are still negative sequence components in the estimated back-electromotive forces(EMFs),which can cause the position estimated *** from conventional methods in which negative sequences are filtered out before the phase-locked loop(PLL)module,the proposed method directly applies the estimated back-EMF with negative sequences as the reference input of *** improved PLL with a bi-quad filter is proposed to attenuate the arising second harmonic position error and heighten the steady-state ***,this position error is used for asymmetric inductance identification and its result is utilized to update the observer ***,the dynamic performance is improved by the output limitation on the bi-quad filter as well as the implementation of a fast-locking technique in the *** effectiveness of the proposed scheme is verified by experimental results.

关键词： Inductance asymmetry Permanent magnet synchronous machine(PMSM) Position estimation error Sensorless control

Subdomain Model for Predicting Armature Reaction Field of Dual-Stator Consequent-Pole PM Machines Accounting for Tooth-Tips

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CES Transactions on Electrical Machines and Systems 2019年第2期3卷 143-150页

作者： Minchen Zhu lijian wu Youtong Fang Thierry Lubin College of Electrical Engineering Zhejiang UniversityChina Universitéde Lorraine France

This paper presents an exact analytical subdomain model of dual-stator consequent-pole permanent-magnet(DSCPPM)machines accounting for tooth-tips,which can accurately predict the armature reaction field distribution in DSCPPM *** the proposed subdomain model,the field domain is composed of four types of sub-regions,***,outer/inner air gaps,slots and slot *** analytical expressions of vector potential in each sub-region are determined by boundary and interface *** comparison to the analytically predicted results,the corresponding flux density field distributions computed by finite element(FE)method are analyzed,which confirms the excellent accuracy of the developed subdomain model.

关键词： Analytical model rmature reaction consequent-pole dual-stator permanent-magnet machines subdomain model.

Driving Range Parametric Analysis of Electric Vehicles Driven by Interior Permanent Magnet Motors Considering Driving Cycles

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CES Transactions on Electrical Machines and Systems 2019年第4期3卷 377-381页

作者： Le Tian lijian wu Xiaoyan Huang Youtong Fang CRRC Zhuzhou Institute ZhuzhouHunanChina College of Electrical Engineering Zhejiang UniversityHangzhouZhejiangChina

This paper presents parametric analysis of driving range of electric vehicles driven by V-type interior permanent magnet motors aiming at maximum driving range,i.e.,minimal total energy consumption of the motors over a driving *** of design parameters including tooth width,slot depth,split ratio(the ratio of inner diameter to outer diameter of the stator),and V-type magnet angle on the energy consumption of the motors and driving range of electric vehicles over a driving cycle is investigated in *** investigation is carried out for two typical driving cycles with different characteristics to represent different conditions:One is high-speed,low-torque cycle-Highway Fuel Economy Test and the other is low-speed,high-torque cycle-Artemis Urban Driving *** shows that for both driving cycles,the same parameters may have different influence on the energy consumption of the motors,as well as driving range of electric vehicles.

关键词： Driving cycle driving range electrical vehicle interior permanent magnet motor.

Model Predictive Current Control with Adaptive-adjusting Timescales for PMSMs

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CES Transactions on Electrical Machines and Systems 2021年第2期5卷 108-117页

作者： Feng Niu Xi Chen Shaopo Huang Xiaoyan Huang lijian wu Kui Li Youtong Fang School of Electrical Engineering Hebei University of Technology College of Electrical Engineering Zhejiang University

A model predictive current control(MPCC)with adaptive-adjusting method of timescales for permanent magnet synchronous motors(PMSMs)is proposed in this paper to improve the dynamic response and prediction accuracy in transient-state,while lessening the computational burden and improving the control performance in *** timescale characteristics of different parts of MPCC,such as signal sampling,prediction calculation,control output,model error correction,are analyzed,and the algorithm architecture of MPCC with multi-timescale is *** difference between reference and actual speed,and the change rate of actual speed are utilized to discriminate the transient state of speed change and load change,***-adjusting method of control period and prediction stepsize are illustrated in detail after operation condition *** results of a PMSM are presented to validate the effectiveness of proposed *** addition,comparative evaluation of single-step MPCC with fixed timescale and proposed MPCC is conducted,which demonstrates the superiority of proposed control strategy.

关键词： Model predictive current control(MPCC) permanent magnet synchronous motor(PMSM) multi-timescale adaptive-adjusting method