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磁质谱高丰度灵敏度阻滞过滤器研制与性能测试

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质谱学报 2024年第5期45卷 600-608页

作者：袁祥龙沈小攀翟利华李飞腾邓虎徐江冯磊李志明西北核技术研究所陕西西安710024

阻滞过滤器是商用磁质谱仪提高丰度灵敏度的关键部件。本研究基于离子光学基本原理,利用离子光学仿真软件SIMION8.1设计了由5个电极构成的阻滞过滤器,其结构小巧,尺寸仅为(40×50×50) mm3。在能量筛选基础上,该阻滞过滤器还具备方向筛... 详细信息

阻滞过滤器是商用磁质谱仪提高丰度灵敏度的关键部件。本研究基于离子光学基本原理,利用离子光学仿真软件SIMION8.1设计了由5个电极构成的阻滞过滤器,其结构小巧,尺寸仅为(40×50×50) mm3。在能量筛选基础上,该阻滞过滤器还具备方向筛选功能,极大地增强了对杂散离子的滤滞能力。将该阻滞过滤器应用于国产热表面电离质谱仪,并进行不同电压条件下传输效率和丰度灵敏度的测试。结果表明,在不影响主离子束传输效率和峰形的基础上,该阻滞过滤器成功将该仪器的丰度灵敏度指标从<2×10^(-6)提升至<5×10^(-9),丰度灵敏度极限为2×10^(-9),优于目前商用热表面电离质谱仪。本文所设计的阻滞过滤器可为国产高性能磁质谱仪的研制提供重要的技术支撑。

关键词：热表面电离质谱(TIMS) 丰度灵敏度阻滞过滤器杂散离子传输效率

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进气氛围对汽油/聚甲氧基二甲醚燃烧的影响

机械设计与制造 2024年第8期402卷 76-79,83页

作者：张吴喆张光德李腾飞武汉科技大学汽车与交通工程学院湖北武汉430065 上海交通大学动力机械与工程教育部重点实验室上海200030

为实现汽油-聚甲氧基二甲醚双燃料发动机的RCCI高效清洁燃烧,运用CONVERGE建立仿真模型,研究了不同进气温度、进气压力对排放和燃烧的影响规律。研究结果表明:进气压力的提高会使燃烧相位提前,放热率峰值先上升后下降;随着进气温度的提... 详细信息

为实现汽油-聚甲氧基二甲醚双燃料发动机的RCCI高效清洁燃烧,运用CONVERGE建立仿真模型,研究了不同进气温度、进气压力对排放和燃烧的影响规律。研究结果表明:进气压力的提高会使燃烧相位提前,放热率峰值先上升后下降;随着进气温度的提高,燃烧相位提前,放热率峰值升高,燃烧持续期变短,且进气温度大于等于330K时,放热率曲线呈现为双峰。进气压力增大到240kPa时能使最大负荷扩展至1.63MPaIMEP,但此时四种污染物的生成量都较高;进气压力在220kPa时,虽然NOx的排放量有所增多,但其他污染物的排放量都较低。进气温度在(320~330)K时动力性和经济性最好,污染物排放量均处于较低的水平。

关键词：聚甲氧基二甲醚进气温度进气压力双燃料 RCCI

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浅谈机动车维修行业发展现状

价值工程 2024年第27期43卷 158-161页

作者：李腾飞骆晓天津市交通运输综合行政执法总队天津300300

随着国民经济水平的不断发展以及人民日益增长的美好生活需要,汽车能够满足人们便捷化、舒适化、个性化的出行需求,使得其逐步成为家庭的必需品。汽车市场在近十年得到蓬勃发展,到2023年我国机动车保有量高达4.35亿量。汽车市场的繁荣... 详细信息

随着国民经济水平的不断发展以及人民日益增长的美好生活需要,汽车能够满足人们便捷化、舒适化、个性化的出行需求,使得其逐步成为家庭的必需品。汽车市场在近十年得到蓬勃发展,到2023年我国机动车保有量高达4.35亿量。汽车市场的繁荣带来了机动车维修行业的扩张与发展,但同时也产生了信访投诉案件居高不下、维修服务意识和专业能力跟不上技术的迭代更新、行业监管力不从心等问题。本文通过文献与调查研究,总结和分析机动车维修行业发展现状,并提出发展建议。

关键词：机动车维修行业发展行业管理

A novel line-symmetric Goldberg 6R linkage with bifurcation property

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Journal of Central South University 2020年第12期27卷 3754-3767页

作者： li Lei li teng-fei DAI Jian-sheng WANG Rui-qin Key Lab for Mechanism Theory and Equipment Design of Ministry of Education International Centre for Advanced Mechanisms and RoboticsTianjin UniversityTianjin 300350China Centre for Robotics Research School of Natural Sciences and MathematicsKing’s College LondonUniversity of LondonLondon WC2R 2LSUnited Kingdom

This paper proposes a novel reconfigurable Goldberg 6R linkage,conformed to the construction of variant serial Goldberg 6R linkage,while simultaneously satisfying the line-symmetric Bricard *** isomeric mechanism of this novel reconfigurable mechanism is obtained in combination with the isomerization *** geometrically constrained conditions result in variable motion branches of the *** on the singular value decomposition of the Jacobian matrix,the motion branches and branch bifurcation characteristics are analyzed,and the schematics of bifurcations in joint space is *** novel 6R linkage features one Goldberg 6R motion branch,two line-symmetric Bricard 6R motion branches,and one Bennett motion *** regards to the line-symmetric Bricard 6R motion branches,a similar function for the disassembly and recombination process can be achieved by reconstructing an intermediate configuration through ***,the isomerized generalized variant Goldberg 6R linkage is explicated in a similar *** as a bridge,reconfigurability connects two families of overconstrained mechanisms.

关键词： overconstrained mechanism reconfigurable mechanism SVD method bifurcation characteristics

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定日镜场效率参数模型的研究

兰州文理学院学报(自然科学版) 2024年第5期38卷 30-36+53页

作者：解慧张建国李舒畅李腾飞程翔晋中学院数学系晋中学院物理系晋中学院信息技术与工程系

针对定日镜场相关效率参数问题，根据几何光学知识，计算出定日镜场中太阳高度角和方位角、每个定日镜与地面的倾角.采用光线追踪法，通过阴影遮挡效率、余弦效率、大气透射率集热器截断效率和镜面反射率构建光学效率参数模型，建立定... 详细信息

针对定日镜场相关效率参数问题，根据几何光学知识，计算出定日镜场中太阳高度角和方位角、每个定日镜与地面的倾角.采用光线追踪法，通过阴影遮挡效率、余弦效率、大气透射率集热器截断效率和镜面反射率构建光学效率参数模型，建立定日镜场的输出热功率的优化模型，在定日镜场达到额定功率的条件下，得出定日镜单位面积镜面平均输出热功率的优值.

关键词：光线追踪法定日镜场几何光学光学效率

Experimental Study on Hydrodynamic Characteristics of Vertical-Axis Floating Tidal Current Energy Power Generation Device

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China Ocean Engineering 2016年第5期30卷 749-762页

作者： MAYong li teng-fei ZHANG liang SHENG Qi-hu ZHANG Xue-wei JIANG Jin College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China

To study the characteristics of attenuation, hydrostatic towage and wave response of the vertical-axis floating tidal current energy power generation device （VAFTCEPGD）, a prototype is designed and experiment is carried out in the towing tank. Free decay is conducted to obtain attenuation characteristics of the VAFTCEPGD, and characteristics of mooring forces and motion response, floating condition, especially the lateral displacement of the VAFTCEPGD are obtained from the towing in still water. Tension response of the #1 mooring line and vibration characteristics of the VAFTCEPGD in regular waves as well as in level 4 irregular wave sea state with the current velocity of 0.6 m/s. The results can be reference for theoretical study and engineering applications related to VAFTCEPGD.

关键词： tidal current energy power generation device experiment hydrodynamic characteristics attenuation wave response lateral displacement

Programmable synthetic receptors:the next-generation of cell and gene therapies

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Signal Transduction and Targeted Therapy 2024年第2期9卷 376-400页

作者： fei teng Tongtong Cui li Zhou Qingqin Gao Qi Zhou Wei li University of Chinese Academy of Sciences Beijing 101408China State Key Laboratory of Stem Cell and Regenerative Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China

Cell and gene therapies hold tremendous promise for treating a range of difficult-to-treat ***,concerns over the safety and efficacy require to be further addressed in order to realize their full *** receptors,a synthetic biology tool that can precisely control the function of therapeutic cells and genetic modules,have been rapidly developed and applied as a powerful *** designed and engineered,they can be applied to finetune the therapeutic activities,i.e.,to regulate production of dosed,bioactive payloads by sensing and processing user-defined signals or *** review provides an overview of diverse synthetic receptor systems being used to reprogram therapeutic cells and their wide applications in biomedical *** a special focus on four synthetic receptor systems at the forefront,including chimeric antigen receptors(CARs)and synthetic Notch(synNotch)receptors,we address the generalized strategies to design,construct and improve synthetic ***,we also highlight the expanding landscape of therapeutic applications of the synthetic receptor systems as well as current challenges in their clinical translation.

关键词： synthetic landscape payload

Temperature prediction model in multiphase flow considering phase transition in the drilling operations

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Petroleum Science 2024年第3期21卷 1969-1979页

作者： Yang Zhang Yong-An li Xiang-Wei Kong Hao liu teng-fei Sun College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100027China School of Petroleum Engineering Yangtze UniversityWuhan430000HubeiChina

The study considers gas compression properties,gas slippage,back pressure(BP),phase transition(PT),well depth,and differences in gas-liquid physical properties.A new temperature model for multiphase flow is proposed by considering phase transition in the drilling *** mathematical model of multiphase flow is solved using the finite difference method with annulus mesh division for grid nodes,and a module for multiphase flow calculation and analysis is *** results indicate that the temperature varies along the annulus with the variation of gas influx at the bottom of the *** the process of controlled pressure drilling,as gas slips along the annulus to the wellhead,its volume continuously expands,leading to an increase in the gas content within the annulus,and consequently,an increase in the pressure drop caused by gas *** temperature increases with the increase in BP and decreases in gas influx rate and wellbore *** gas influx,the thermal conductivity coefficient for the gas-drilling mud two phases is significantly weakened,resulting in a considerable change in temperature along the *** the context of MPD,the method of slightly changing the temperature along the annulus by controlling the back pressure is feasible.

关键词： Managed pressure drilling Phase transition Temperature Gas-drilling mud two phase

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给袋式灌装技术对油茶育苗基质灌装的启示

林业机械与木工设备 2024年第8期52卷 4-9页

作者：李腾飞苗振坤刘然李世晓张奇曹有为东北林业大学机电工程学院黑龙江哈尔滨150006 国家林业和草原局哈尔滨林业机械研究所黑龙江哈尔滨150086

近年来,油茶经济快速发展,产业规模不断增长,对油茶优质苗木的需求也逐年提高。其中,油茶育苗基质灌装作为培育油茶优质苗木的关键环节,仍主要依靠人工劳动,耗时耗力,作业强度大,生产效率低,缺乏针对育苗基质灌装的现代化机械设备,这些... 详细信息

近年来,油茶经济快速发展,产业规模不断增长,对油茶优质苗木的需求也逐年提高。其中,油茶育苗基质灌装作为培育油茶优质苗木的关键环节,仍主要依靠人工劳动,耗时耗力,作业强度大,生产效率低,缺乏针对育苗基质灌装的现代化机械设备,这些情况严重限制其潜在市场规模和经济效益。主要对给袋式灌装技术进行总体介绍,对关键部件取袋机构、撑袋机构、定量灌装机构的研究情况进行阐述,并分析油茶育苗基质灌装现状,其中包括育苗基质构成、所选用的育苗容器特点以及现在常见的灌装作业方式,最后总结出给袋式灌装技术对应用到油茶育苗基质灌装的启示。为我国油茶育苗基质灌装机构的研究提供参考,促进油茶灌装机械水平的提高。

关键词：油茶给袋式灌装育苗基质育苗容器

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