Magnetic field and Vacuum arc of new TMF-AMF
磁性材料术语解释及计算公式
磁性材料术语解释及计算公式起始磁导率μi初始磁导率是磁性材料的磁导率（B/H ）在磁化曲线始端的极限值，即μi =01μ× H B ∆∆ ()0→∆H式中μ0为真空磁导率（m H /7104-⨯π） ∆H 为磁场强度的变化率（A/m ）∆B 为磁感应强度的变化率（T ）有效磁导率μe在闭合磁路中，如果漏磁可忽略，可以用有效磁导率来表示磁芯的性能。
e μ =AeLe N L 20⋅μ 式中 L 为装有磁芯的线圈的电感量（H ）N 为线圈匝数Le 为有效磁路长度（m ）Ae 为有效截面积 (m 2)饱和磁通密度Bs （T ）磁化到饱和状态的磁通密度。
见图1。
HcH图 1剩余磁通密度Br（T）从饱和状态去除磁场后，剩余的磁通密度。
见图1。
矫顽力Hc（A/m）从饱和状态去除磁场后，磁芯继续被反向磁场磁化，直至磁感应强度减为零，此时的磁场强度称为矫顽力。
见图1。
损耗因子tanδ损耗系数是磁滞损耗、涡流损耗和剩余损耗三者之和。
tanδ= tanδh + tanδe + tanδr式中tanδh为磁滞损耗系数tanδe为涡流损耗系数tanδr为剩余损耗系数相对损耗因子 tanδ/μi比损耗因子是损耗系数与与磁导率之比：tanδ/μi（适用于材料）tanδ/μe（适用于磁路中含有气隙的磁芯）品质因数 Q品质因数为损耗因子的倒数: Q = 1/ tan δ温度系数αμ( 1/K)温度系数为T1和T2范围内变化时,每变化1K 相应的磁导率的相对变化量:αμ=112μμ-μ.12T T 1- 式中μ1为温度为T1时的磁导率μ2为温度为T2时的磁导率 相对温度系数αμr(1/K)温度系数和磁导率之比，即αμr = 2112μμ-μ.12T T 1- 减落系数 DF在恒温条件下，完全退磁的磁芯的磁导率随时间的衰减变化，即 DF = 212121μ1T T log μμ⨯- (T2>T1) μ1为退磁后T1分钟的磁导率μ2为退磁后T2分钟的磁导率居里温度Tc （℃）在该温度时材料由铁磁性（或亚铁磁）转变为顺磁性，见图2。
电器电子英语词汇（M）_科技英语词汇
m type backward wave tube m 型返波振荡管m type tube m 型电子管m type twt m 型行波管machine ringing 机械振铃macroblock 宏模块macrocell 宏单元macrocell approach 宏单元技术macrocell array 宏单元阵列made to order integrated circuit 定制集成电路madistor 晶体磁控管magazine 盒magnet 磁石magnet core aerial 磁心天线magnet core antenna 磁心天线magnetic amplification 磁放大magnetic amplifier 磁放大器magnetic bias 磁偏置magnetic bubble device 磁泡掐magnetic bubble domain chip 磁泡芯片magnetic bubble memory 磁泡存储器magnetic confinement of plasma 等离子区的磁密封magnetic convergence 磁会聚magnetic core 磁心magnetic deflection 磁偏转magnetic dipole 磁偶极子magnetic domaine storage 磁泡存储器magnetic double refraction 磁场致双折射magnetic drum 磁鼓magnetic drum memory 磁鼓存储器magnetic field 磁场magnetic field applied lec 施加磁场液封直拉法magnetic film 磁性薄膜magnetic flux 磁通量magnetic focusing 磁聚焦magnetic head 磁头magnetic head core 磁头铁心magnetic head gap 磁头缝隙magnetic head gap depth 磁头缝隙深度magnetic head gap length 磁头缝隙长度magnetic head gap width 磁头缝隙宽度magnetic intensity 磁场强度magnetic lens 磁透镜magnetic lines of force 磁力线magnetic medium 磁介质magnetic microphone 电磁传声器magnetic modulator 磁灯器magnetic permeability 磁导率magnetic pumping 磁激励magnetic recording 磁记录magnetic rotation of polarized light 极化光的磁致旋转magnetic semiconductor 磁性半导体magnetic static wave 静磁波magnetic storm 磁暴magnetic susceptibility 磁化率magnetic tape 磁带magnetic trap 磁捕集器magnetics 磁学magnetizing field 磁化场magneto bell 交羚铃magneto ionic wave component 磁离子波分量magneto optical deflector 磁光偏转器magneto optical modulator 磁光灯器magnetoacoustic delay line 磁声延迟线magnetohydrodynamic laser 磁铃力学激光器magnetohydrodynamic pumping 磁铃动力抽运magnetohydrodynamic waves 磁铃波magnetohydrodynamics 磁性铃动力学magnetooptic memory 磁光存储器magnetooptics 磁光学magnetoresistance 磁阻magnetoresistive effect 磁阻效应magnetoresistor 磁阻器magnetostatic wave device 静磁波掐magnetostriction oscillator 磁致伸缩振荡器magnetostriction transducer 磁致伸缩式换能器magnetostrictive delay line 磁致伸缩延迟线magnetron 磁控管magnetron amplifier 磁控管放大器magnetron ion etcher 磁控管离子腐蚀装置magnetron oscillator 磁控管振荡器magnetron sputtering 磁控管溅射magnetron vacuum gage 磁控管真空计magnification 放大magnified image 放大的图象main exchange 电话总局main gap 咒隙main group 趾main lobe 吱瓣main oscillator 竹荡器main signal 峙号main station 用户助mains receiver 交劣收机maintainability 维修性major lobe 吱瓣majority carrier 多数载劣majority current 多数载劣电流majority emitter 多数载劣发射极majority gate 多数决定门majority logic 多数逻辑malfunction 机能不良man made noise 人为噪声manual calling 人工呼叫manual editing 手动编辑manual exchange 人工电话局manual insertion 手动装配manual ringing 人工呼叫manual telephone system 人工电话系统manufacturability 可制造性manufacturing line 生产线manufacturing method 制造方法manufacturing tolerance 制造公差many layer mirror 多层镜many valley semiconductor 多谷半导体maos structure 金属氧化铝氧化物半导体结构margin of safety 安全裕度marginal check 边缘检查marginal sharphness 边缘清晰度marginal test 边缘检查marine electronics 海洋电子学maritime satellite communication 海洋卫星通信mark 标记mark space ratio 线圈间隙因数marker antenna 指点信标天线marker pip 集成电路外壳的标记点marking 钻记marking current 传局电流maser 脉泽maser amplification 脉泽放大maser amplifier 脉泽放大器maser beam 微波激射束maser oscillator 脉泽振荡器maser radiation 脉泽辐射maser transition 脉泽跃迁maser transmitter 脉泽发射机mask 掩模mask aligner 掩模对准器mask artwork 掩模原图mask carrier 掩模载运体mask cassette 掩模盒mask copy 掩模复制mask definition 掩模图案形成mask degradation 掩模老化mask distortion 掩模扭曲mask feature 掩模图形单元mask holder 掩模架mask hole 掩模窗mask inspection tool 掩模检查工具mask layout 掩模草图mask level 掩模层次mask lifetime 掩模寿命mask lithography 掩模光刻mask making facilities 掩模制造设备mask membrane 掩蔽膜mask opening 掩模窗孔mask overlay comparator 掩模重迭比较器mask overlay error 掩模相互重合误差mask pack 掩模包mask pattern 掩模图案mask pattern generator 掩模图案发生器mask pattern layout 掩模图形布置图mask programmable array 掩模可编程序阵列mask programmable chip 掩模可编程序芯片mask programmable integration 掩模可编程序集成电路mask programmable memory 掩模可编程序存储器mask replication 掩模复制mask replicator 掩模复制器mask resolution 掩模清晰度mask scrubber 掩模洗涤器mask set 掩模组mask superposition error 掩模相互重合误差mask tolerance 掩模容许偏差maskant 掩蔽体masked diffusion 掩蔽扩散masked ion implantation 掩蔽离子注入masking 掩蔽masking film 掩蔽膜masking layer 掩蔽层masking oxide 掩蔽氧化物masking pattern 掩模图案masking photoresist 掩蔽光刻胶masking plate 掩蔽板maskless ion implantation 无掩模离子注入maskless pattern generation 无掩模图像生成mass bonding 群焊mass soldering 成批焊接mass spectrometer 质谱仪mass spectrometer leak detector 质谱检漏仪mass spectroscopy 质谱仪master 原图master chip 志片master drawing 原图master group 趾master layout 掩模总布置图master mask 母掩模master monitor 粥视器master mos approach mos结构母片方法master oscillator 重振荡器master picture monitor 旨像监视器master plate 母掩模master reticle 掩模原版master transmitter 症射机masterslice 母片masterslice approach 母片方法masterslice integrated circuit 母片型集成电路masterslice personalization 母片专用化mat 微合金晶体管matched beam 匹配束matched filter 匹配滤波器matched junction 匹配连接matched line 匹配线matched load 匹配荷载matched termination 匹配荷载matched transmission line 匹配传输线matched waveguide 匹配波导管matching 匹配matching attenuator 匹配衰减器matching diaphragm 匹配膜片matching reactance 匹配电抗matching section 匹配段matching strip 匹配带matching transformer 匹配变压器matrix 矩阵matrix addressed display 矩阵寻址显示器matrix addressing 矩阵寻址matrix circuit 矩阵变换电路matrix display 矩阵显示器matrix integrated circuit 矩阵型集成电路matrix large scale integration 矩阵型大规模集成电路maximum deflection 最大偏转maximum load 最大负载maximum range 最大探测距离maximum usable frequency 最高可用频率maxwellian distribution 麦克斯韦分布mbd 磁泡掐mbe 分子束外延mbm 磁泡存储器mbt 金属基极晶体管mccd 曲折型沟道电荷耦合掐mcvd 改进的化学汽相淀积mean energy density 平均能量密度mean error 平均误差mean free path 平均自由路程mean free time 平均自由飞行时间mean frequency 平均频率mean life 平均寿命mean time between failures 平均故障间隔时间mean time to failure 平均故障间隔时间meander ccd 曲折型沟道电荷耦合掐measurement 测量measurement probe 测量探针measuring amplifier 测量用放大器measuring bridge 测量用电桥measuring device 测量装置measuring error 测量误差measuring microphone 测量传声器mechanical failure 机械故障mechanical recording 机械记录mechanical scanning 机械扫掠mechanism of crystal growth 晶体生长机理mechanism of nucleation 成核机理medical laser 医用激光器medical television 医学用电视medium 载波medium complexity 中规模集成度medium frequency 中频medium scale integration 中规模集成度medium waves 中波megachip 百万级规模集成电路megascale ic 百万级规模集成电路megatron 塔形电子管meissner oscillator 麦斯南振荡器melt 熔融meltback 回熔melting 熔融membrane 膜membrane mask 薄膜型掩模memory 存储器memory capacity 记忆容量memory chip 存储凭片memory controller 存储曝制器memory density 存储密度memory device 记亿设备memory effect 记忆效应memory management chip 存储栖理集成电路memory mapping 存储单元布置memory transistor 存储晶体管memory unit 存储单元memoscope 存储管式示波器mercury arc rectifier 水银整流mercury diffusion pump 水银扩散泵mercury vapor 水银蒸汽merged n p n load 合并 n p n 负载merged structure 合并结构merged transistor logic 合并晶体管逻辑mesa 台面结构mesa epitaxial approach 台面外延工艺mesa etching 台面腐蚀mesa island 台面型岛mesa recess 台面槽mesa structure 台面结构mesa transistor 台面式晶体管mesa type transistor 台面型晶体管mesfet 金属半导体场效应晶体管mesh 电池mesh emitter 网状发射极mesh network 网状网络mesh size 网目尺寸meshed network 网状网络meson factory 介子发生器mesopause 中间层顶mesosphere 中间层message 报文message register 通话计次器message routing 报文路径选择message switching 报文交换messanger call 传呼metadyne 旋转式磁场放大机metal alumina oxide semiconductor structure 金属氧化铝氧化物半导体结构metal base transistor 金属基极晶体管metal ceramic 金属陶瓷metal ceramic package 金属陶瓷外壳metal definition 金属层图像形成metal detector 金属探测器metal etch resist 金属腐蚀用光刻胶metal evaporation 金属蒸镀metal evaporator 金属蒸发器metal film 金属薄膜metal film resistor 金属薄膜电阻器metal gate electrode 金属栅电极metal gate technique 金属栅技术metal gate transistor 金属栅晶体管metal insulator metal 金属绝缘体金属结构metal insulator semiconductor 金属绝缘体半导体metal insulator semiconductor fet mis场效应晶体管metal mask 金属掩模metal nitride oxide semiconductor structure mnos结构metal nitride semiconductor 金属氮化物半导体metal on glass mask 金属玻璃掩模metal oxide resistor 金属氧化物电阻器metal oxide semiconductor 金属氧化物半导体metal oxide semiconductor field effect transistor 金属氧化物半导体场效应晶体管metal oxide semiconductor silicon on sapphire 蓝宝石上硅型金属氧化物半导体metal oxide semiconductor transistor load mos负载晶体管metal photomask 金属光掩模metal quality block 金属化质量试验装置metal schottky fet 金属肖特基栅场效应晶体管metal screen printing 金属丝网漏印刷法metal self aligned process 金属自对准工艺metal semiconductor barrier 金属半导体接触势垒metal semiconductor device 金属半导体接触掐metal semiconductor interface 金属半导体界面metal semiconductor junction 金属半导体结metal semiconductor metal 金属半导体金属结构metal silicide interconnection 金属硅化物互连metal system 金属化系统metal vapor laser 金属蒸汽激光器metallic mirror 金属镜metallic vapor laser 金属蒸汽激光器metallization 金属化metallization deposition 金属化淀积metallization mask 金属化掩模metallization masking 金属化掩蔽metallization pattern 金属化图形metallization routing 金属化路由metallized screen 金属背荧光屏metallized semiconductor fet 金属半导体场效应晶体管metallo organic chemical vapor deposition 有机金属化学汽相淀积metallo organic vapor phase epitaxy 有机金属汽相外延metallographic section 金相试片metallographical microscope 金相显微镜metallurgy 冶金学metastable atom 亚稳原子metastable condition 亚稳状态metastable level 亚稳能级metastable state 亚稳状态metering relay 计数继电器metre ampere 米安mf 中频mgt 金属栅晶体管mhd laser 磁铃力学激光器mic 单片集成电路microalloy junction 微合金结microalloy transistor 微合金晶体管microassembly 微型组件microcapacitor 微型电容器microchannel image tube 微通道摄像管microchannel multiplier 微通道倍增器microchannel plate 微通道板microchip 微型芯片microchip resistor 微型片状电阻器microcircuit 微型电路microcircuit element 微型电路元件microcircuit engineering 微型电路工程学microcircuit layout design 微型电路布图设计microcircuitry 微型电路技术microcleaned surface 显微清洁表面microcoded microprocessor 微编码微处理机microcomponent 微型元件microcomputer 微型电子计算机microcontroller 微型控制器microdefinition 缩微成像microdiscrete device 微型分立掐microelectronic chemical agent 微电子工业用化学试剂microelectronic circuit 微型电子电路microelectronic packaging 微型电子掐封装microelectronic technology 微电子技术microelectronics 微电子学microelement 微型元件microfabrication 微型品制造microfilm resistor 微薄膜电阻器microfunction circuit 微功能电路micrograph 显微照片microgravity processing 微重力状态下处理microimaging 缩微成像microinterconnection 微型互连microinterferometer 显微干涉仪microlayer transistor 微层晶体管microlithographic patterning 显微光刻图像形成microlithography 显微光刻法micromachining 显微机械加工micromain frame 微型助micrometer lithography 微米结构光刻microminiaturization 超小型化micromodule 微型组件micron lithography 微米结构光刻micron scale integrated circuit 微米尺寸集成电路micron sized geometry 微米尺寸几何形状microoptoelectronics 微型光电子学microorganism battery 微生物电池micropattern 微型图象micropatterning 缩微成像microphone 传声器microphone amplifier 话筒放大器microphone directivity 传声聘向性microphone noise 传声齐声microphonic effect 颤噪效应microphotolithography 显微光刻术microplating 微电镀micropositioner 微动台micropositioning table 微型定位台micropower integration 微功率集成电路micropower transistor 微功率晶体管microprinted circuit 微型印刷电路microprinter 微型印刷机microprobe 微探针microprocessor 微处理机microprocessor automated sputterer 微处理曝制的溅射装置microprocessor chip 微型处理机芯片microprocessor controlled bonder 微处理曝制的热压焊装置microprocessor integrated circuit 微型处理机芯片microprocessor kit 微处理凭片组microprocessor modem 微处理机灯解调microprocessor set 微处理凭片组microprocessor slice 位片微处理机microprogrammed microprocessor 微编码微处理机microradiometer 微辐射计microresistor 微型电阻器microsection 显微磨片microshaving 微膜剥去microstage 微型定位台microstrip line 微波带状线microsurface profile 表面微剖面图microtrace 微量轨迹microtron 电子回旋加速器microtronics 微电子学microvoltmeter 微伏计microwatt logic 微瓦逻辑电路microwave absorption 微波吸收剂microwave antenna 微波天线microwave baking 微波热处理microwave discharge 微波放电microwave discriminator 微波鉴频器microwave eye 微波眼microwave ferrite 微波铁氧体microwave gyrator 微波回转器microwave holography 微波全息照相术microwave integrated circuit 微波集成电路microwave laminate 微波迭层板microwave logic 微波逻辑电路microwave oscillator 微波发生器microwave plasma etching 微波等离子体腐蚀microwave power measurement 微波功率测量microwave radiometry 微波辐射测量microwave receiver 微波接收机microwave region 微波波段microwave semiconductor 微波半导体掐microwave spectrometer 微波频谱仪microwave television receiver 微波电视接收机microwave tube 微波管mid frequency 中频mid range microprocessor 中挡微型机middle frequency 中频middle marker 中点指标midget set 小型接收机mig 多层互连信号发生器migration 移位mild etching 轻腐蚀milic 毫米波图像带宽集成电路miller effect 密勒效应miller indices 密勒指数miller integrator 密勒积分器millimeter wave antenna 毫米波天线millimeter wave image line integrated circuit 毫米波图像带宽集成电路millimeter wave laser 毫米波激光器millimeter wave monolithic integrated circuit 毫米波单片集成电路millioscilloscope 小型示波器milliteslameter 毫泰斯拉计miltronics 军用电子学mim 金属绝缘体金属结构mimic 毫米波单片集成电路mini laser 小型激光器miniature valve 小型管miniaturization 小型化minimum detectable signal 最小可探测信号miniprober 极小型探测仪miniscope 小型示波器minor carrier 少数载劣minor exchange 电话支局minority carrier current 少数载劣电流minority carrier device 少数载劣掐mip 多列直插式外壳mirror 镜mirror finish 镜面抛光mirror image 镜像mis 金属绝缘体半导体mis logic 金属绝缘体半导体结构逻辑电路mis transistor mis晶体管misalignment 不对准misfet mis场效应晶体管misfire 弧误mismatch 不匹配mismatch loss 失配损耗misregistration 不对准mitron 可淀带磁控管mix match lithography 混纺拼色光刻mixed bed demineralizer 混合床脱盐器mixed process 混合工艺mixed semiconductor 混合半导体mixed techmology 混合工艺mixer 混合器mixer unit 混合器mixing tube 混频管mixing valve 混频管mixture ratio 混合比mlb 多层印刷板mlc 多层陶瓷mli 多层互连mlm 多层金属化mm pulse radar 毫米波脉冲雷达mnos structure mnos结构mnos transistor 金属氮化物氧化物半导体晶体管mns 金属氮化物半导体moat 槽mobile carrier 可动载劣mobile laser tracking and ranging system 活动激光追踪与测距系统mobile radio 移动式无线电通信mobile transmitter 移动式发射机mobility enhancement 迁移率增加mockup 实体模型mocvd 有机金属化学汽相淀积mocvd reactor 有机金属化学汽相淀积反应器modal noise 模式噪声mode 模式mode converter 模变换器mode filter 振荡型滤波器mode of resonance 谐振摸modem 灯解调modem chip 灯解稻片modified chemical vapor deposition 改进的化学汽相淀积modular circuit 棋块电路modular station 标准化装置modularity 组件方式modularizaion 模块化modulated aerial 党的天线modulated carrier 巳地波modulated wave 灯波modulating signal 灯信号modulation 灯modulation capability 灯能modulation characteristic 灯特性modulation code 灯码modulation cpapbility 灯能力modulation element 灯元件modulation factor 灯系数modulation frequency 灯频率modulation index 灯指数modulation meter 灯度测试器凋制计modulation method 灯法modulation noise 灯噪声modulation percentage 灯度modulation rate 灯速率modulation stage 灯级modulator 灯器modulator demodulator 灯解调modulator tube 灯管module 组件moire 网纹干扰moisture barrier 防湿层moisture content 湿气含量moisture meter 湿度计moisture resistance 防潮性moisture sensor 湿敏元件mold 铸模molded assembly 模制组件molded case 模制管壳molded package 模制管壳molder 塑模机molding 浇铸molecular beam deposition 分子束淀积molecular beam epitaxy 分子束外延molecular electronics 分子电子学molecular gun 分子枪molecular impurity 分子杂质molecular integrated circuit 分子集成电路molelectronics 分子电子学mom capacitor 金属氧化物金属电容器monitor 监视器monitor desk 监听台monitor receiver 检验收报器monitoring 监视monitoring amplifier 监听放大器monitoring loudspeaker 监听扬声器monitoring signal 监听信号monitoring system 监视系统monoatomic layer 单原子层monobrid 单片混合组装monobrid circuit 单片混合电路monochromatic light 单色光monochromatic pumping 单色激励monochromatic radiation 单色辐射monochrome hologram 单色全息图monochrome receiver 黑白电视信号接收机monochrome signal 单色信号monochrome signal bandwidth 单色信号带宽monochrome transmission 单色发送monocord 单塞绳monocrystal 单晶monocrystalline reconversion 单晶的再结晶monolayer 单分子层monolithic cell 单片单元monolithic circuit 单片电路monolithic component 单片元件monolithic functional device 单片功能掐monolithic integrated circuit 单片集成电路monolithic integration 单片集成电路monolithic memory 单片存储器monolithic microcircuit 单片微型电路monolithic microprocessor 单片微处理器monolithic operation amplifier 单片运算放大器monolithic oscillator 单片式振荡器monolithic processor 单片处理机monolithic resistor 单片电阻器monolithic sample hold 取样保持单片电路monolithic structure 单片结构monomode laser 单模激光器monomode lightguide 单模光波导monomolecular film 单分子膜monomolecular layer 单分子层monophonic recording 单声道录音monophony 单声技术monopulse 单脉冲monopulse optical receiver 单脉冲式光接收机monopulse radar 单脉冲雷达monoscope 单像管monostable blocking oscillator 单稳间歇振荡器monostable circuit 单稳态电路monostable multivibrator 单稳多谐振荡器monte carlo method 蒙特卡罗法monte carlo modelling 蒙特卡罗法模拟morphology of crystals 晶体形态学morse apparatus 莫尔斯电报机morse code 莫尔斯符号morse ink writer 莫尔斯印字机morse key 莫尔斯电键morse printer 莫尔斯印字机mos 金属氧化物半导体mos array integrated circuit mos阵列集成电路mos capacitor mos电容器mos insulated gate transistor 绝缘栅金属氧化物半导体晶体管mos ion implantation mos结构离子注入mos logic mos逻辑mos technology mos工艺mos transistor mos晶体管mos transistor circuit mos晶体管电路mos transistor logic mos晶体管逻辑mos wafer mos结构薄片mos/sos 蓝宝石上硅型金属氧化物半导体mosaic 感光嵌镶幕mosaic array 镶嵌矩阵mosaic crystal 镶嵌晶体mosaic photocathode 镶嵌光阴极mosaic telegraphy 嵌镶幕电报mosfet 金属氧化物半导体场效应晶体管mosfet gate 金属氧化物半导体场效应晶体管门电路most mos晶体管mostl mos晶体管逻辑motion picture holography 全息电影mount 支架mountain effect 山地效应mounting 安装mounting cable 装配电缆mounting equipment 组装设备mounting hole 安装孔mouthpiece 话期承moving coil loudspeaker 动圈式扬声器moving target indication radar 活动目标显示雷达moving target indicator 活动目标显示器moviola 音象同步装置mp 单片处理机msi 中规模集成度msi circuit 中规模集成电路msld 质谱检漏仪msm 金属半导体金属结构msw 静磁波msw device 静磁波掐mtbf 平均故障间隔时间mtl 合并晶体管逻辑mttf 平均故障间隔时间muffler 消声器multi cavity klystron 多腔蒂管multi channel 多信道的multi channel telegraphy 多路电报multi frequency system 多频制multiatmosphere furnace 多气氛炉multiband antenna 多频带天线multiband loudspeaker 多频带扬声器multibeam irradiation 多光束辐照multibeam tube 多束管multiburst 多波群multicarrier transmitter 多载波发射机multicavity magnetron 多腔磁控管multichamber etcher 多室腐蚀装置multichannel fet 多通道场效应晶体管multichannel mixer 多路混合器multichannel oscillator 多信道振荡器multichannel recording 多声道录音multichannel transmission 多路传输multichannel transmitter 多路发射机multichip array 多芯片集成电路multichip assembly 多片组装multichip assembly technique 多片组装技术multichip carrier 多片载体multichip circuit 多芯片集成电路multichip hybrid 多片混合电路multichip ic 多芯片集成电路multichip microprocessor 多片微处理机multichip module 多片组件multichip system 多芯片系统multicolor display 多色显示器multicolor hologram 多色全息照相multicolor laser 多色激光器multicomponent glass 多成分玻璃multicore cable 多芯电缆multidimensional modeling 多维模拟multidimensional simulation 多维模拟multidrop line 多点线路multielectrode tube 多极管multielement photodetector 多元件光电探测器multiemitter transistor 多发射极晶体管multifiber cable 多纤维光缆multifiber lightguide 多纤维光波导multifrequency code 多频码multifrequency code signal 多频码信号multifrequency signal 多频信号multifrequency transmitter 多频发射机multifunction microcircuit 多功能微电路multifunction radar 多功能雷达multifunctional module 多功能组件multigap cavity 多隙共振腔multiheterostructure 多异质结结构multiheterostructure laser 多异质结结构激光器multiimage 多重图象multijunction photocell 多结光电池multilaser optical radar 多元激光雷达multilayer board 多层印刷板multilayer capacitor 多层电容器multilayer ceramic 多层陶瓷multilayer chip carrier 多层芯片载体multilayer circuit 多层电路multilayer element 多层元件multilayer film 多层膜multilayer integrated circuit 多层集成电路multilayer interconnection 多层互连multilayer lightguide 多层光波导multilayer metallization 多层金属化multilayer mirror 多层镜multilayer package 多层外壳multilayer semiconductor device 多层半导体掐multilayer structure 多层结构multilayer substrate 多层衬底multilead chip 多引线芯片multileaded flat pack 多插脚扁平封装multilevel circuit 多层集成电路multilevel insulator 多层绝缘体multilevel integration 多层集成电路multilevel interconnection 多层互连multilevel interconnection generator 多层互连信号发生器multilevel logic 多值逻辑multilevel oxide 多层氧化物multilevel system 多电平系统multimask processing 多掩模工艺multimeter 万用表multimode cavity 多模谐振腔multimode fiber 多模光纤维multimode film 多模膜multimode laser 多模激光器multimode lightguide 多模光波导multimode line 多模传输线multimode resonator 多模谐振腔multimode waveguide 多模波导管multipactor 大功率快速微波开关掐multipactor discharge 电子倍增放电multipair cable 多对绞电缆multipath reflection 多路反射multipattern matrix 多重图像矩阵multiphoton ionization 多光子电离multiphoton laser 多光子激光器multiphoton photoelectric emission 多光子光电发射multiphoton transition 多光子跃迁multipin package 多插脚外壳multiple antenna 多单元天线multiple backscattering 多次反散射multiple chip microprocessor 多片微处理机multiple collision 多次碰撞multiple connector 多路插头multiple diffusion 多次扩散multiple fiber 纤维束multiple gate finger fet 多梳形栅场效应晶体管multiple image generation 多重成象multiple image lens 多重图像透镜multiple imaging 多重成象multiple in line package 多列直插式外壳multiple ionization 多次电离multiple layer lightguide 多层光波导multiple light fiber 光学纤维束multiple modulation 多重灯multiple pulse laser 多脉冲激光器multiple reception 多次接收multiple reflection 多次反射multiple scanning 多重扫描multiple signal 多重信号multiple stage deposition 多段淀积multiple step and repeat machine 多路步进重复照相机multiple substrate technique 多片技术multiple switch 复联开关multiple switchboard 复式交换机multiple target 多目标multiple tuned aerial 复奠线multiple tuned antenna 复奠线multiple unit tube 复合管multiple wire antenna 多线天线multiplex switch 多路灯器multiplex system 多路制multiplex telegraphy 多路电报multiplex telephony 多路电话multiplexer 多路灯器multiplexing 多路传输multiplication 倍增multiplication circuit 乘法电路multiplication ratio 倍增系数multiplier 倍增器multiplier phototube 光电倍增器multiplier tube 倍增管multiplying tube 电子倍增管multipoint line 多点线路multipoint probe 多点探针multispectral microwave imaging radar 多谱微波成象雷达multistage photodetector 多级光电探测器multistage solar cell 多级太阳电池multistage switching 多级交换multitrack recording 多声道录音multivalued logic 多值逻辑multivariable control theory 多变量控制理论multivariable nonlinear feedback system 多变量非线性反馈系统multivariable optimal control techniques 多变量最优控制技术multivariable output feedback system 多变量输出反馈系统multivariate feedback 多变量反馈multivibrator 多谐振荡器multiwafer plasma oxidizer 多圆片等离子体氧化装置multiwafer plasma reactor 多圆片等离子体反应器multiwire 多线连接musa antenna 复合菱形天线mush 噪声music synthesizer 音乐合成器mutual induction 互感mutual repulsion 相互推斥。
磁性测量术语
magnetic field 磁场elementary magnetic dipole 基本磁偶极子Magnetically hard material 永磁/硬磁材料electrical steel 电工钢Magnetically soft material 软磁材料semi-processed 半力口工remanence 剩磁(卜.Br) maximum polarization 最大磁极化强度Remanent flux density 剩余磁通密度domain wall 畴壁coercivity 矫顽力(HcB) Coercive field strength-矫顽力intrinsic coercivity 内禀矫顽力(HcJ) field strength 磁场强度Magnetic induction 磁感应强度B electric potential 电位maximum energy product 最大磁能积BH(max) moment 磁矩1但)退磁曲线8(用磁滞回线polarisation磁极化强度magnetic flux density 磁通密度magnetic hysteresis 磁滞fluxmeter 磁通计manometer 压力计comunication interface 通讯接口gausser高斯计(磁强计)coercimeter矫顽磁力计vibrometer测振仪permeameter 磁导计feebly magnetic material 弱磁材料saturation magnetization饱和磁化强度fixture 固定装置saturation magnetic polarization 饱和磁极化强度Saturation magnetization (mass) density 饱和磁化(质量)密度Specificsaturation magnetization 比饱和磁化强度Magnetic dipole moment 磁偶极矩incremental loop 增量回线gnetic moment 磁矩magnetic potential 磁位eddy current loss 涡流损耗curve 曲线100P 回线commutation curve 换向曲线Magnetic anisotropy 磁各向异性magnetic texture 磁织构Induced magnetic anisotropy 感生磁各向异性Magnetic anisotropic substance 磁各向异性物质Grain-oriented material晶体取向材料drill钻头fuse保险丝Thermally neutralized state 热致磁中性状态virgin state 初始状态Technical Specification 技术协议Drift 漂移NIM National Institute of Metrology 中国计量科学研究院IEC International Electrotechnical Comission 国际电工技术委员会DIN Deutsch Industrial Norman 德国标准German Institute of Standardization GB 国标ASTM 标准:American Society for Testing Material 美国试验材料学会QMS: Quality Management System 质量管理系统housing 测量主机temperature pole caps 高温极头thermocouple 热电偶Thermal element 热敏原件surrounding coils 环绕线圈integrated heating elements 集成力□热元件Room Temperature measurement 常温测量Pole Measuring 极头测量Segment pole coils 瓦型极头线圈Internal calibration 内部校准field coil场线圈pole coil极头线圈(arc) segment 瓦形square shape 方形Cubic 立方体Cylindrical圆柱体cylinder n.汽缸；圆柱状物ellipsoid椭圆体ring measuring cable 环行测量线Reference Samples 标准样品Ferrite Reference Sample 铁氧体标准样品Measuring range 测量范围NdFeB Reference Sample铉铁硼标准样品Resolution分辨率Shrink fitting 冷缩配合/烧嵌radial compression 径向压缩Nickel Reference Sample 银标准样品Permanent Magnet 永磁体3D-Helmholtz Coil三维亥姆霍兹线圈Electro magnet 电磁铁changeable pole cap 可更换极头voltage generator 电压发生器voltage integrator 电压积分器voltage indicator 电压指示器Measuring desk with Container 测量桌带货柜Integrator with very low drift with 24 bit A/D-converter积分器低漂移带24bit A/D转换器Windows-program多窗口界面Input resistance 输入电阻Interfaces 接口Connectors:Thermovoltage miniconnectors 连接器：热电压微型连接器data bank数据库printer打印机curves测量曲线data storage in an EXCEL-compatible 数据存储Excel 兼容Heating module 力口热模块Pole cap diameter 极头直径Inner diameter 内径temperature poles 温度极头thermovoltage mini socket 热电压微型插座Homogeneous Dia 平均直径Pole Face Dia 极面直径with feeder clamp connection 与馈线夹连接Incl. BROCKHAUS-Certificate 带Brockhaus 计量证书Allocation of filenames 分配文件名称depending on air-gap and pole cap 取决于空气间隙与极头Electrical drawings 电气图Mechanical drawings 机械图Drawings of part lists 零部件图Hardware set up 硬件调试LDR abbr.光敏电阻(light dependentresistor) PLM 脉冲宽度调制(Pulse-Length Modulation) PWM abbr.脉冲宽度调制(Pulse-Width Modulation) carbon fiber碳化纤维，碳素纤维optical fiber光纤，光导纤维steel fiber钢纤维；金属纤维fiber laser纤维激光器AlNiCo铝银钻ferrite铁氧体SmCo钐Shan钻磁铁NdFeB 铉铁硼slitting 分条single notching 单冲槽Steel plate shearer 剪板机interlocking with orientation 定向铆接Design and manufacture of carbide dies硬质合金模具的设计和制造Annealing and steam bluing 退火和发蓝core welding 铁芯焊接Plastic overmoulding 注塑rotor die casting 转子压铸Shaft insertion with liquid nitrogen 液态氮轴压入ventilation 通风设备Shaft production and assembling 轴的生产和组装aerospace 航空/天Axial轴向的radial辐射的multipolar多极的skewed偏斜的Amorphous alloy 非晶态合金cemented carbides硬质合金Austenitic stainless steel 奥氏体不锈钢solenoid 螺旋管Plasma cutting machine等离子切割机carbide stamping硬质合金冲压Blanking 落料notching 槽冲plastic overmoulding 注塑生产线Automatic press machine 自动压缩机high corrosion 高耐腐蚀性Low temperature coefficients 低温度系数scanner 扫描仪Parallelogram平行四边形diagonal对角线，斜的Generator stator and rotor parts 发电机定转子部件Pressure-riveting 压铆 laminations for automobile motor 汽车电机铁芯 EV Electron Volt 电子伏特 HEV Hybrid Electrical Vehicle 混合动力汽车Profilograph 轮廓曲线仪纵断面测绘仪表面光度仪Communication protocol （计算机）通讯协议 vacuum plate 真空板 Sucker 吸盘 torque force 扭力stamping 冲压 annealing 退火welding 焊接Actuator motor 执行器电机crane stator 起重机用电机定子Synergy 协同cocking-up 上翘Hydraulic pump 液压驱动 vibration free table 减震桌Electric cabinet 电控柜 barrier frequency 截至频率 Homogeneous primary windings 均匀的初级绕组Horizontal transmissibility 水平性传输resonance 协振 Elliptically rotation 椭圆旋转angular velocity 角速度 A real time acquisition system 实时采集系统phase control 相差 lead time 投产前准备阶段interlocking 咬合 gluing 粘合 Clamping 固定/夹紧burr 毛边/铁屑 anneal 退火/韧炼 Amortization 分期偿还 elongation 延展力 coax plug 共轴插头 Exciting current 励磁电流 software editor 软件编辑器 Hydraulic cylinder 液压缸log files 记录文件/日志文件Unloading problems 卸货问题trolly 货车/推车vacuum pumps 真空泵 Bending machine 折床 warranty guarantee 授权保证Meeting minutes 会议纪要 rectangular/sinusoidal wave 矩形波/正弦波 magnetizing current 励磁电流 amplitude stability 放大稳定性 The integral of the secondary voltage 次级电压的积分measuring gauge(n. 计量器；)测量仪 Function generator 信号发生器 Using Wattmeter-Ammeter-Voltmeter Method 用功率表/电流表/电压表 ARCNET interface-card ARCNET 网络接口卡等NO material 无取向试样 Magnetic displacement 磁位移 PO 是指采购订单生产计划是依据客户的采购订单（客户PO ） Ambit 范围/周围gauge 测量器 mechanical lifters 机械升起装置 connection screws 螺钉连接 solenoidn.［电］螺线管；螺线形电导管control loop 控制回路 Higher Harmonics 高次谐波Higher centrifugal force 高离心力Ceramic 陶瓷的Load cell 称重传感器/测力传感器G-clamp 螺旋夹钳 OD/ID(outside/inside diameter)外直径/内直径Sintered magnet 烧结磁铁slot ripple 线槽脉冲 thermal demagnetization 热退磁setup, commissioning (acceptance test)设定、命令(接收测试)operation of machine, Trouble shooting, calibration and adjustment and maintenance 机器操作、问题处理、校正与调试维护radium 半径 Magnetic moment 磁矩 helmholtz coil 亥姆霍兹线圈 DC Bias 直流偏磁 control algorithm 控制算法 strain gauge 变形测量器 sample clamp 样品夹。
关于电磁场的英文作文
关于电磁场的英文作文英文回答：Electromagnetic fields are a fundamental aspect of our modern world. They are all around us, from the electricity that powers our homes to the signals that allow us to communicate wirelessly. Understanding electromagneticfields is essential for many aspects of our daily lives.One of the key concepts in electromagnetism is the idea of electric and magnetic fields. These fields are invisible, but they have a significant impact on the world around us. Electric fields are created by electric charges, such asthe positive and negative charges in a battery. Magnetic fields, on the other hand, are created by moving electric charges, such as the current flowing through a wire.These fields interact with each other and with charged particles, creating a wide range of phenomena. For example, when an electric field and a magnetic field areperpendicular to each other, they can produce a force that causes a charged particle to move in a circular path. Thisis the principle behind the operation of a particle accelerator.Electromagnetic fields also play a crucial role in the transmission of information. Radio waves, for instance, are a type of electromagnetic wave that carries signals fromone place to another. We use radio waves to listen to music, talk on our cell phones, and watch television. Without electromagnetic fields, these technologies would not be possible.In addition to their practical applications, electromagnetic fields also have some interesting properties. For example, they can be described by mathematical equations known as Maxwell's equations. These equations provide a comprehensive description of howelectric and magnetic fields behave and interact with each other. They have been instrumental in the development of modern physics and engineering.中文回答：电磁场是我们现代世界的一个基本方面。
E电流的磁场
Discuss： ： Long straight solenoid： β1 = π , β 2 = 0
⊗⊗⊗⊗⊗⊗⊗
B = µ 0 nI
Inside the solenoid, the B every point are equality. β1 = π , β 2 = π / 2 µ 0 nI One end of half-solenoid: B= 2 β1 = π / 2, β 2 = π Direction: axis direction
equal to µ0 times the algebraic sum of the currents
Several distributing of magnetic field line
A long straight wire
A circular current
Magnetic field lines of a solenoid
4 Magnetic flux 磁通量
The magnetic flux passing through a surface S is defined by the surface integral: v v Φm = ∫ dΦm = ∫ BdS cos α dΦm = B ⋅ dS = BdS cd Magnetic Induction
1 Magnetic field 磁场
v 2 Magnetic Induction 磁感应强度 B
Current or Magnet
Magnetic field
Current or Magnet
The magnetic force on motionless charges is zero. The magnetic force on moving charges can be tested. The electric field was defined by means of the force on the charge at rest The magnetic field can be defined by examining the force on moving charges v Direction The force on moving charges is zero B Fmax (T) Magnitude B = qv
真空中的恒定磁场(双语)
Magnetic Flux Density, Field Equations Boundary Conditions
1. Magnetic Flux Density, Flux, and Field Lines 2. Equations for Steady Magnetic Fields in Free Space 3. Vector & Scalar Magnetic Potentials 4. Magnetization of Media 5. Equations for Steady Magnetic Fields in A Medium 6. Boundary Conditions for Steady Magnetic Fields
Experiments show that the magnetic force acting on a moving charge is related not only to the magnitude and the speed of the charge, but also to the direction of motion.
v
B
F
In-line Direction
Assuming the maximum force is Fm, if the angle between the direction of charge motion and the in-line direction is , the force will be
We
define
a
vector
B
whose
magnitude
is
Magnetic
Magnetic HealingDecember 30, 2007Our body is a magnetic field and our tissues contain magnetite. There is a significant amount of magnetite near the pineal gland in the brain. The pineal gland secretes hormones throughout the body.Magnetic healing (or magnetic therapy) is a form of alternative medicine involving magnetic fields. Ardent proponents claim that subjecting certain parts of the body to doses of magnetic fields has a beneficial effect. This belief has led to the popularization of an industry involving the sale of magnetic-based products for "healing" purposes: magnetic bracelets and jewelry; magnetic straps for wrists, ankles and the back; shoe insoles, mattresses and magnetic blankets; and even water that has been "magnetized". Magnetic products in the market come in various strengths, shapes, sizes and forms. The price varies from the nominal to very expensive depending on what kinds of materials are used.Magnetic healing is not a new concept. It was used by ancient civilizations thousands of years ago, including the Egyptians and the Greeks. Aristotle expounded on the use of magnets as a therapeutic means of healing sometime around 350 BC. The Greek physician Galan used magnets to heal in 200 BC. Persian physicians were treating muscle spasms with magnets in 1000. Paracelsus, a Swiss physician, advocated magnetic therapy in the 1500s.The therapy is said to work in a non-invasive way to cure many painful conditions, primarily back disorders, arthritis and joint aches by directly affixing the magnets on the painful part of the body. The therapy makes use of the static magnetic fields produced by permanent magnets, involving the application of electromagnetic waves to the patient. Magnetic fields from permanent magnets are said to speed up the healing process of the body and relieve pains. Some of the common ailments treated using magnetic therapy are insomnia, carpal tunnel syndrome, arthritis, headaches, and backaches. It is believed that magnets must be placed precisely in order to reap the full effect of the treatment. When a magnet is put on the affected area of the body, it relaxes the walls of the capillaries, hence increasing the flow of blood to the painful area. They are also said to interfere with muscle contractions, thus preventing muscle spasms, which are thought to be the underlying cause of many types of pain. Plus, magnets impede the ability of nerve cells to transmit pain messages to the brain. While over-the-counter pain relieving medications like aspirin can be used to control chronic pain, however, magnets do not have any risk of side effects.Magnet therapy is most effective when used in conjunction with other forms of alternative healing therapies like acupuncture. Being placed at pressure points to relieve soreness, magnets open up microscopic blood vessels and facilitate better blood flow. Conversely, magnets can also be used to change the direction of blood flow and thus prevent the spread of inflammation.However, the mainstream scientific community generally considers the therapy pseudoscientific.。
纳米颗粒尺寸、形状以及界面效应对介电和击穿场强等因素的影响
Society Chem.Mater.2010,22,1567–15781567DOI:10.1021/cm902852hNanoparticle,Size,Shape,and Interfacial Effects on Leakage Current Density,Permittivity,and Breakdown Strength of MetalOxide-Polyolefin Nanocomposites:Experiment and TheoryNeng Guo,†Sara A.DiBenedetto,†Pratyush Tewari,‡Michael nagan,*,‡Mark A.Ratner,*,†and Tobin J.Marks*,††Department of Chemistry and the Materials Research Center,Northwestern University,Evanston, Illinois60208-3113and‡Center for Dielectric Studies,Materials Research Institute,The Pennsylvania State University,University Park,Pennsylvania16802-4800Received September11,2009.Revised Manuscript Received December2,2009A series of0-3metal oxide-polyolefin nanocomposites are synthesized via in situ olefin polymeriza-tion,using the following single-site metallocene catalysts:C2-symmetric dichloro[rac-ethylenebisindenyl]-zirconium(IV),Me2Si(t BuN)(η5-C5Me4)TiCl2,and(η5-C5Me5)TiCl3immobilized on methylaluminoxane (MAO)-treated BaTiO3,ZrO2,3-mol%-yttria-stabilized zirconia,8-mol%-yttria-stabilized zirconia, sphere-shaped TiO2nanoparticles,and rod-shaped TiO2nanoparticles.The resulting composite materials are structurally characterized via X-ray diffraction(XRD),scanning electron microscopy(SEM), transmission electron microscopy(TEM),13C nuclear magnetic resonance(NMR)spectroscopy,and differential scanning calorimetry(DSC).TEM analysis shows that the nanoparticles are well-dispersed in the polymer matrix,with each individual nanoparticle surrounded by polymer.Electrical measurements reveal that most of these nanocomposites have leakage current densities of∼10-6-10-8A/cm2;relative permittivities increase as the nanoparticle volume fraction increases,with measured values as high as6.1. At the same volume fraction,rod-shaped TiO2nanoparticle-isotactic polypropylene nanocomposites exhibit significantly greater permittivities than the corresponding sphere-shaped TiO2nanoparticle-isotactic polypropylene nanocomposites.Effective medium theories fail to give a quantitative description of the capacitance behavior,but do aid substantially in interpreting the trends qualitatively.The energy storage densities of these nanocomposites are estimated to be as high as9.4J/cm3.IntroductionFuture pulsed-power and power electronic capacitors will require dielectric materials with ultimate energy storage den-sities of>30J/cm3,operating voltages of>10kV,and milli-second-microsecond charge/discharge times with reliable operation near the dielectric breakdown limit.Importantly, at2and0.2J/cm3,respectively,the operating characteristics of current-generation pulsed power and power electronic capacitors,which utilize either ceramic or polymer dielectric materials,remain significantly short of this goal.1An order-of-magnitude improvement in energy density will require the development of dramatically different types of materials, which substantially increase intrinsic dielectric energy den-sities while reliably operating as close as possible to the die-lectric breakdown limit.For simple linear response dielectric materials,the maximum energy density is defined in eq1,U e¼12εrε0E2ð1Þwhereεr is the relative dielectric permittivity,E the dielec-tric breakdown strength,andε0the vacuum permittivity (8.8542Â10-12F/m).Generally,metal oxides have large permittivities;however,they are limited by low breakdown fields.While organic materials(e.g.,polymers)can provide high breakdown strengths,their generally modest permit-tivities have limited their application.1Recently,inorganic-polymer nanocomposite materials have attracted great interest,because of their potential for high energy densities.2By integrating the complementary*Authors to whom correspondence should be addressed.E-mail addresses: mxl46@(M.T.L.),ratner@(M.A.R.),and t-marks@(T.J.M.).(1)(a)Pan,J.;Li,K.;Li,J.;Hsu,T.;Wang,Q.Appl.Phys.Lett.2009,95,022902.(b)Claude,J.;Lu,Y.;Li,K.;Wang,Q.Chem.Mater.2008, 20,2078–2080.(c)Chu,B.;Zhou,X.;Ren,K.;Neese,B.;Lin,M.;Wang,Q.;Bauer,F.;Zhang,Q.M.Science2006,313,334–336.(d) Cao,Y.;Irwin,P.C.;Younsi,K.IEEE Trans.Dielectr.Electr.Insul.2004,11,797–807.(e)Nalwa,H.S.,Ed.Handbook of Low and High Dielectric Constant Materials and Their Applications;Academic Press:New York,1999;V ol.2.(f)Sarjeant,W.J.;Zirnheld,J.;MacDougall,F.W.IEEE Trans.Plasma Sci.1998,26,1368–1392.(2)(a)Kim,P.;Doss,N.M.;Tillotson,J.P.;Hotchkiss,P.J.;Pan,M.-J.;Marder,S.R.;Li,J.;Calame,J.P.;Perry,J.W.ACS Nano 2009,3,2581–2592.(b)Li,J.;Seok,S.I.;Chu,B.;Dogan,F.;Zhang, Q.;Wang,Q.Adv.Mater.2009,21,217–221.(c)Li,J.;Claude,J.;Norena-Franco,L.E.;Selk,S.;Wang,Q.Chem.Mater.2008,20, 6304–6306.(d)Gross,S.;Camozzo,D.;Di 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(17)Rabuffi,M.;Picci,G.IEEE Trans.Plasma Sci.2002,30,1939–1942.Article Chem.Mater.,Vol.22,No.4,20101569polyolefin -ferroelectric permittivity contrast.If too large,such contrasts are associated with diminished breakdown strength and suppressed permittivity.18,19In a brief preliminary communication,we reported evidence that high-energy-density BaTiO 3-and TiO 2-isotactic polypropylene nanocomposites could be pre-pared via in situ propylene polymerization mediated by anchoring/alkylating/activating C 2-symmetric dichloro-[rac -ethylenebisindenyl]zirconium(IV)(EBIZrCl 2)on the MAO-treated oxide nanoparticles (see Scheme 1).20The resulting nanocomposites were determined to have rela-tively uniform nanoparticle dispersions and to support remarkably high projected energy storage densities ;as high as 9.4J/cm 3,as determined from permittivity and dielectric breakdown measurements.In this contribution,we significantly extend the inorganic inclusion scope to include a broad variety of nanoparticle types,to investi-gate the effects of nanoparticle identity and shape on the electrical/dielectric properties of the resulting nanocom-posites,and to compare the experimental results with theoretical predictions.We also extend the scope of metallocene polymerization catalysts (see Chart 1)and olefinic monomers,with the goal of achieving nanocom-posites that have comparable or potentially greater pro-cessability and thermal stability.Here,we present a full discussion of the synthesis,microstructural and electrical characterization,and theoretical modeling of these nano-composites.It will be seen that nanoparticle coating with MAO and subsequent in situ polymerization are crucial to achieving effective nanoparticle dispersion,and,simul-taneously,high nanocomposite breakdown strengths (as high as 6.0MV/cm)and high permittivities (as high as 6.1)can be realized to achieve energy storage densities as high as 9.4J/cm 3.Experimental SectionI.Materials and Methods.All manipulations of air-sensitive materials were performed with rigorous exclusion of O 2and moisture in flamed Schlenk-type glassware on a dual-manifold Schlenk line or interfaced to a high-vacuum line (10-5Torr),or in a dinitrogen-filled MBraun glovebox with a high-capacity recirculator (<1ppm O 2and H 2O).Argon (Airgas,pre-purified),ethylene (Airgas,polymerization grade),and propy-lene (Matheson or Airgas,polymerization grade)were purified by passage through a supported MnO oxygen-removal column and an activated Davison 4A molecular sieve column.Styrene (Sigma -Aldrich)was dried sequentially for a week over CaH 2and then triisobutylaluminum,and it was freshly vacuum-transferred prior to polymerization experiments.The monomer 1-octene (Sigma -Aldrich)was dried over CaH 2and was freshly vacuum-transferred prior to polymerization experiments.To-luene was dried using activated alumina and Q-5columns,according to the method described by Grubbs,21and it was additionally vacuum-transferred from Na/K alloy and stored in Teflon-valve sealed bulbs for polymerization experiments.Ba-TiO 3and TiO 2nanoparticles were kindly provided by Prof.Fatih Dogan (University of Missouri,Rolla)and Prof.Thomas Shrout (Penn State University),respectively.20ZrO 2nanopar-ticles were purchased from Sigma -Aldrich.The reagents 3-mol %-yttria-stabilized zirconia (TZ3Y)and 8-mol %-yttria-stabilized zirconia (TZ8Y)nanoparticles were purchased from Tosoh,Inc.TiO 2nanorods were purchased from Reade Ad-vanced Materials (Riverside,RI).All of the nanoparticles were dried in a high vacuum line (10-5Torr)at 80°C overnight to remove the surface-bound water,which is known to affect the dielectric breakdown performance adversely.22The deuteratedScheme 1.Synthesis of Polyolefin -Metal OxideNanocompositesChart 1.Metallocene polymerization catalysts andMAO.(18)(a)Li,J.Y.;Zhang,L.;Ducharme,S.Appl.Phys.Lett.2007,90,132901/1–132901/3.(b)Li,J.Y .;Huang,C.;Zhang,Q.M.Appl.Phys.Lett.2004,84,3124–3126.(19)Cheng,Y.;Chen,X.;Wu,K.;Wu,S.;Chen,Y.;Meng,Y.J.Appl.Phys.2008,103,034111/1–034111/8.(20)Guo,N.;DiBenedetto,S.A.;Kwon,D.-K.;Wang,L.;Russell,M.T.;Lanagan,M.T.;Facchetti,A.;Marks,T.J.J.Am.Chem.Soc.2007,129,766–767.(21)Pangborn,A.B.;Giardello,M.A.;Grubbs,R.H.;Rosen,R.K.;Timmers,anometallics 1996,15,1518–1520.(22)(a)Hong,T.P.;Lesaint,O.;Gonon,P.IEEE Trans.Dielectr.Electr.Insul.2009,16,1–10.(b)Ma,D.;Hugener,T.A.;Siegel,R.W.;Christerson,A.;M artensson,E.;€Onneby,C.;Schadler,L.S.Nano-technology 2005,16,724–731.(c)Ma,D.;Siegel,R.W.;Hong,J.;Schadler,L.S.;M artensson,E.;€Onneby,C.J.Mater.Res.2004,19,857–863.1570Chem.Mater.,Vol.22,No.4,2010Guo et al. solvent1,1,2,2-tetrachloroethane-d2was purchased fromCambridge Isotope Laboratories(g99at.%D)and was usedas-received.Methylaluminoxane(MAO;Sigma-Aldrich)waspurified by removing all the volatiles in vacuo from a1.0Msolution in toluene.The reagents dichloro[rac-ethylenebisin-denyl]zirconium(IV)(EBIZrCl2),and trichloro(pentamethyl-cyclopentadienyl)titanium(IV)(Cp*TiCl3)were purchasedfrom Sigma-Aldrich and used as-received.Me2Si(t BuN)(η5-C5Me4)TiCl2(CGCTiCl2)was prepared according to publishedprocedures.23nþ-Si wafers(root-mean-square(rms)roughnessof∼0.5nm)were obtained from Montco Silicon Tech(SpringCity,PA),and aluminum substrates were purchased fromMcMaster-Carr(Chicago,IL);both were cleaned according to standard procedures.24II.Physical and Analytical Measurements.NMR spectra were recorded on a Varian Innova400spectrometer(FT400 MHz,1H;100MHz,13C).Chemical shifts(δ)for13C spectra were referenced using internal solvent resonances and are reported relative to tetramethylsilane.13C NMR assays of polymer microstructure were conducted in1,1,2,2-tetrachlor-oethane-d2containing0.05M Cr(acac)3at130°C.Resonances were assigned according to the literature for isotactic polypro-pylene,poly(ethylene-co-1-octene),and syndiotactic polystyr-ene,respectively(see more below).Elemental analyses were performed by Midwest Microlabs,LLC(Indianapolis,IN). Inductively coupled plasma-optical emission spectroscopy (ICP-OES)analyses were performed by Galbraith Laboratories, Inc.(Knoxville,TN).Powder X-ray diffraction(XRD)patterns were recorded on a Rigaku DMAX-A diffractometer with Ni-filtered Cu K R radiation(λ=1.54184A).Pristine ceramic nanoparticles and composite microstructures were examined with a FEI Quanta sFEG environmental scanning electron microscopy(SEM)system with an accelerating voltage of30 kV.Transmission electron microscopy(TEM)was performed on a Hitachi Model H-8100TEM system with an accelerating voltage of200kV.Samples for TEM imaging were prepared by dipping a TEM grid into a suspension of nanocomposite powder in acetone.Polymer composite thermal transitions were mea-sured on a temperature-modulated differential scanning calori-meter(TA Instruments,Model2920).Typically,ca.10mg of samples were examined,and a ramp rate of10°C/min was used to measure the melting point.To erase thermal history effects, all samples were subjected to two melt-freeze cycles.The data from the second melt-freeze cycle are presented here.III.Electrical Measurements.Metal-insulator-metal (MIM)or metal-insulator-semiconductor(MIS)devices for nanocomposite electrical measurements were fabricated by first doctor-blading nanocomposite films onto aluminum(MIM)or nþ-Si(MIS)substrates,followed by vacuum-depositing top gold electrodes through shadow masks.Specifically,a clean substrate was placed on a hot plate heated to just below the polymer-nanocomposite melting point.A small amount of the polymer nanocomposite powder was placed in the center of the substrate and left until the powder began to melt.Once in this phase,the polymer nanocomposite is spread over the center of the sub-strate using a razor blade.The sample was removed from the heat,cooled,and then pressed in a benchtop press to ensure uniform film thicknesses and smooth surfaces.Gold electrodes 500A thick were vacuum-deposited directly on the films through shadow masks that defined a series of different areas (0.030,0.0225,0.01,0.005,and0.0004cm2)at3Â10-6Torr(at 0.2-0.5A/s).Electrical properties of the films were character-ized by two probe current-voltage(I-V)measurements using a Keithley Model6430Sub-Femtoamp Remote Source Meter, operated by a local LABVIEW program.Triaxial and low triboelectric noise coaxial cables were incorporated with the Keithley remote source meter and Signatone(Gilroy,CA)probe tip holders to minimize the noise level.All electrical measure-ments were performed under ambient conditions.For MIS devices,the leakage current densities(represented by the symbol J,given in units of A/cm2)were measured with positive/negative polarity applied to the gold electrode to ensure that the nþ-Si substrate was operated in accumulation.A delay time of1s was incorporated into the source-delay-measure cycle to settle the source before recording currents.Capacitance measurements of the MIM and MIS structures were performed with a two-probe digital capacitance meter(Model3000,GLK Instruments,San Diego,CA)at(5and24kHz.Several methods have been developed to measure the dielectric breakdown strength of polymer and nanocomposite films.1a,25In this study,various methods were examined(e.g.,pull-down electrodes25),and the two-probe method was used to collect the present data because the top gold electrodes had already been deposited for leakage current and capacitance measurements.The dielectric break-down strength of the each type of composite film was measured in a Galden heat-transfer fluid bath at room temperature with a high-voltage amplifier(Model TREK30/20A,TREK,Inc., Medina,NY)with a ramp rate of1000V/s.26The thicknesses of the dielectric films were measured with a Tencor P-10step profilometer,and these thicknesses were used to calculate the dielectric constants and breakdown strengths of the film sam-ples(see Table2,presented later in this work).IV.Representative Immobilization of a Metallocene Catalyst on Metal Oxide Nanoparticles.In the glovebox,2.0g of BaTiO3 nanoparticles,200mg of MAO,and50mL of dry toluene were loaded into a predried100-mL Schlenk reaction flask,which was then attached to the high vacuum line.Upon stirring,the mixture became a fine slurry.The slurry was next subjected to alternating sonication and vigorous stirring for2days with constant removal of evolving CH4.Next,the nanoparticles were collected by filtration and washed with fresh toluene(50mLÂ4) to remove any residual MAO.Then,200mg of metallocene catalyst EBIZrCl2and50mL of toluene were loaded in the flask containing the MAO-coated nanoparticles.The color of the nanoparticles immediately became purple.The slurry mixture was again subjected to alternating sonication and vigorous Table1.XRD Linewidth Analysis Results for the Oxide-PolypropyleneNanocompositespowder2θ(deg)full width athalf maximum,fwhm(deg)crystallitesize,L(nm)a BaTiO331.4120.25435.6 BaTiO3-polypropylene31.6490.27132.8 TiO225.3600.31727.1 TiO2-polypropylene25.3580.36123.5a Crystallite size(L)is calculated using the Scherrer equation:L=0.9λ/[B(cosθB)whereλis the X-ray wavelength,B the full width at half maximum(fwhm)of the diffraction peak,andθB the Bragg angle.(23)Stevens,J.C.;Timmers,F.J.;Wilson,D.R.;Schmidt,G.F.;Nickias,P.N.;Rosen,R.K.;Knight,G.W.;Lai,S.Eur.Patent Application EP416815A2,1991.(24)Yoon,M.-H.;Kim,C.;Facchetti,A.;Marks,T.J.J.Am.Chem.Soc.2006,128,12851–12869.(25)Claude,J.;Lu,Y.;Wang,Q.Appl.Phys.Lett.2007,91,212904/1–212904/3.(26)Gadoum,A.;Gosse,A.;Gosse,J.P.Eur.Polym.J.1997,33,1161–1166.Article Chem.Mater.,Vol.22,No.4,20101571stirring overnight.The nanoparticles were then collected by filtration and washed with fresh toluene until the toluene remained colorless.The nanoparticles were dried on the high-vacuum line overnight and stored in a sealed container in the glovebox at-40°C in darkness.V.Representative Synthesis of an Isotactic Polypropylene Nanocomposite via In Situ Propylene Polymerization.In the glovebox,a250-mL round-bottom three-neck Morton flask, which had been dried at160°C overnight and equipped with a large magnetic stirring bar,was charged with50mL of dry toluene,200mg of functionalized nanoparticles,and50mg of MAO.The assembled flask was removed from the glovebox and the contents were subjected to sonication for30min with vigorous stirring.The flask was then attached to a high vacuum line(10-5Torr),the catalyst slurry was freeze-pump-thaw degassed,equilibrated at the desired reaction temperature using an external bath,and saturated with1.0atm(pressure control using a mercury bubbler)of rigorously purified propylene while being vigorously stirred.After a measured time interval,the polymerization was quenched by the addition of5mL of methanol,and the reaction mixture was then poured into800 mL of methanol.The composite was allowed to fully precipitate overnight and was then collected by filtration,washed with fresh methanol,and dried on the high vacuum line overnight to constant weight.VI.Representative Synthesis of a Poly(ethylene-co-1-octene) Nanocomposite via In Situ Ethyleneþ1-Octene Copolymeriza-tion.In the glovebox,a250-mL round-bottom three-neck Morton flask,which had been dried at160°C overnight and equip-ped with a large magnetic stirring bar,was charged with50mL of dry toluene,200mg of functionalized nanoparticles,and 50mg of MAO.The assembled flask was removed from the glo-vebox and the contents were subjected to sonication for30min with vigorous stirring.The flask was then attached to a high vacuum line(10-5Torr),the catalyst slurry was freeze-pump-thaw degassed,equilibrated at the desired reaction temperature using an external bath,and saturated with1.0atm(pressure control using a mercury bubbler)of rigorously purified ethylene while being vigorously stirred.Next,5mL of freshly vacuum-transferred1-octene was quickly injected into the rapidly stirred flask using a gas-tight syringe equipped with a flattened spraying needle.After a measured time interval,the polymerization was quenched by the addition of5mL of methanol,and the reaction mixture was then poured into800mL of methanol.The com-posite was allowed to fully precipitate overnight and was then collected by filtration,washed with fresh methanol,and dried on the high vacuum line overnight to constant weight.Film fabri-cation of the composite powders into thin films for MIS electrical testing was unsuccessful due to the high incorporation level of1-octene.VII.Representative Synthesis of a Syndiotactic Polystyrene Nanocomposite via In Situ Styrene Polymerization.In the glove-box,a250-mL round-bottom three-neck Morton flask,which had been dried at160°C overnight and equipped with a large magnetic stirring bar,was charged with50mL of dry toluene, 200mg of functionalized nanoparticles,and50mg of MAO.The assembled flask was removed from the glovebox and the con-tents were subjected to sonication for30min with vigorous stirring.The flask was then attached to a high vacuum line(10-5 Torr)and equilibrated at the desired reaction temperature usingTable2.Electrical Characterization Results for Metal Oxide-Polypropylene Nanocomposites aentry compositenanoparticlecontent b(vol%)melting temperature,T m c(°C)permittivity dbreakdownstrength e(MV/cm)energy density,U f(J/cm3)1BaTiO3-iso PP0.5136.8 2.7(0.1 3.1 1.2(0.1 2BaTiO3-iso PP0.9142.8 3.1(1.2>4.8>4.0(0.6 3BaTiO3-iso PP 2.6142.1 2.7(0.2 3.9 1.8(0.2 4BaTiO3-iso PP 5.2145.6 2.9(1.0 2.7 1.0(0.3 5BaTiO3-iso PP 6.7144.8 5.1(1.7 4.1 3.7(1.2 6BaTiO3-iso PP13.6144.8 6.1(0.9>5.9>9.4(1.37s TiO2-iso PP g0.1135.2 2.2(0.1>2.8>0.8(0.1 8s TiO2-iso PP g 1.6142.4 2.8(0.2 4.1 2.1(0.2 9s TiO2-iso PP g 3.1142.6 2.8(0.1 2.8 1.0(0.1 10s TiO2-iso PP g 6.2144.8 3.0(0.2 4.7 2.8(0.211r TiO2-iso PP h 1.4139.7 3.4(0.3 1.00.40(0.35 12r TiO2-iso PP h 3.0142.4 4.1(0.70.90.22(0.09 13r TiO2-iso PP h 5.1143.7 4.9(0.40.90.23(0.0814ZrO2-iso PP 1.6142.9 1.7(0.3 1.50.1815ZrO2-iso PP 3.9145.2 2.0(0.4 1.90.3216ZrO2-iso PP7.5144.9 4.8(1.1 1.00.2017ZrO2-iso PP9.4144.4 6.9(2.6 2.0 1.02(0.7318TZ3Y-iso PP 1.1142.9 1.1(0.1N/A N/A19TZ3Y-iso PP 3.1143.5 1.8(0.2N/A N/A20TZ3Y-iso PP 4.3143.8 2.0(0.2N/A N/A21TZ3Y-iso PP 6.7144.9 2.7(0.2N/A N/A22TZ8Y-iso PP0.9142.9 1.4(0.1 3.8 1.07(0.04 23TZ8Y-iso PP 2.9143.2 1.8(0.1 2.80.5924TZ8Y-iso PP 3.8143.2 2.0(0.2 2.00.4125TZ8Y-iso PP 6.6146.2 2.4(0.4 2.20.61a Polymerizations performed in50mL of toluene under1.0atm of propylene at20°C.b From elemental analysis.c From differential scanning calorimetry(DSC).d Derived from capacitance measurements.e Calculated by dividing the breakdown voltage by the film thickness,which is measured using a Tencor p10profilometer.f Energy density(U)is calculated from the following relation:U=0.5ε0εr E b2,whereε0is the permittivity of a vacuum,εr the relative permittivity,and E b the breakdown strength.g The superscripted prefix“s”denotes sphere-shaped TiO2nanoparticles.h The superscripted prefix“r”denotes rod-shaped TiO2nanoparticles.。
磁性测量术语
magnetic field 磁场elementary magnetic dipole 基本磁偶极子Magnetically hard material 永磁/硬磁材料electrical steel电工钢Magnetically soft material 软磁材料semi-processed半加工remanence 剩磁(Jr. Br) maximum polarization 最大磁极化强度Remanent flux density 剩余磁通密度domain wall畴壁coercivity 矫顽力(HcB) Coercive field strength-矫顽力intrinsic coercivity内禀矫顽力(HcJ) field strength磁场强度Magnetic induction 磁感应强度B electric potential 电位maximum energy product最大磁能积BH(max) moment磁矩J(H)退磁曲线B(H)磁滞回线polarisation 磁极化强度magnetic flux density磁通密度magnetic hysteresis磁滞fluxmeter 磁通计manometer压力计comunication interface 通讯接口gausser高斯计(磁强计) coercimeter矫顽磁力计vibrometer测振仪permeameter 磁导计feebly magnetic material弱磁材料saturation magnetization饱和磁化强度fixture 固定装置saturation magnetic polarization 饱和磁极化强度Saturation magnetization (mass) density 饱和磁化(质量)密度Specific saturation magnetization 比饱和磁化强度Magnetic dipole moment 磁偶极矩incremental loop增量回线gnetic moment磁矩magnetic potential磁位eddy current loss涡流损耗curve曲线loop回线commutation curve换向曲线Magnetic anisotropy 磁各向异性magnetic texture 磁织构Induced magnetic anisotropy 感生磁各向异性Magnetic anisotropic substance磁各向异性物质Grain-oriented material晶体取向材料drill钻头fuse保险丝Thermally neutralized state 热致磁中性状态virgin state初始状态Technical Specification 技术协议Drift漂移NIM National Institute of Metrology中国计量科学研究院IEC International Electrotechnical Comission国际电工技术委员会DIN Deutsch Industrial Norman 德国标准German Institute of Standardization GB国标ASTM标准: American Society for Testing Material 美国试验材料学会QMS: Quality Management System质量管理系统housing 测量主机temperature pole caps 高温极头thermocouple 热电偶Thermal element热敏原件surrounding coils 环绕线圈integrated heating elements集成加热元件Room Temperature measurement 常温测量Pole Measuring极头测量Segment pole coils瓦型极头线圈Internal calibration内部校准field coil 场线圈pole coil极头线圈(arc) segment 瓦形square shape 方形Cubic立方体Cylindrical圆柱体cylinder n.汽缸；圆柱状物ellipsoid椭圆体ring measuring cable 环行测量线Reference Samples 标准样品Ferrite Reference Sample 铁氧体标准样品Measuring range测量范围NdFeB Reference Sample 钕铁硼标准样品Resolution分辨率Shrink fitting冷缩配合/烧嵌radial compression径向压缩Nickel Reference Sample 镍标准样品Permanent Magnet永磁体3D-Helmholtz Coil 三维亥姆霍兹线圈Electro magnet 电磁铁changeable pole cap可更换极头voltage generator 电压发生器voltage integrator电压积分器voltage indicator 电压指示器Measuring desk with Container测量桌带货柜Integrator with very low drift with 24 bit A/D-converter积分器低漂移带24bit A/D转换器Windows-program多窗口界面Input resistance输入电阻Interfaces接口Connectors:Thermovoltage miniconnectors连接器：热电压微型连接器data bank数据库printer打印机curves测量曲线data storage in an EXCEL-compatible数据存储Excel兼容Heating module加热模块Pole cap diameter极头直径Inner diameter内径temperature poles温度极头thermovoltage mini socket热电压微型插座Homogeneous Dia 平均直径Pole Face Dia 极面直径with feeder clamp connection与馈线夹连接Incl. BROCKHAUS-Certificate带Brockhaus计量证书Allocation of filenames分配文件名称depending on air-gap and pole cap取决于空气间隙与极头Electrical drawings电气图Mechanical drawings机械图Drawings of part lists零部件图Hardware set up硬件调试LDR abbr. 光敏电阻（light dependent resistor）PLM 脉冲宽度调制（Pulse-Length Modulation）PWM abbr. 脉冲宽度调制（Pulse-Width Modulation）carbon fiber 碳化纤维，碳素纤维optical fiber 光纤，光导纤维steel fiber 钢纤维；金属纤维fiber laser 纤维激光器AlNiCo 铝镍钴ferrite 铁氧体SmCo钐Shan钴磁铁NdFeB 钕铁硼slitting分条single notching单冲槽Steel plate shearer剪板机interlocking with orientation定向铆接Design and manufacture of carbide dies 硬质合金模具的设计和制造Annealing and steam bluing 退火和发蓝core welding 铁芯焊接Plastic overmoulding注塑rotor die casting转子压铸Shaft insertion with liquid nitrogen 液态氮轴压入ventilation通风设备Shaft production and assembling 轴的生产和组装aerospace航空/天Axial 轴向的radial辐射的multipolar多极的skewed偏斜的Amorphous alloy非晶态合金cemented carbides硬质合金Austenitic stainless steel奥氏体不锈钢solenoid 螺旋管Plasma cutting machine等离子切割机carbide stamping硬质合金冲压Blanking落料notching槽冲plastic overmoulding 注塑生产线Automatic press machine自动压缩机high corrosion高耐腐蚀性Low temperature coefficients 低温度系数scanner扫描仪Parallelogram 平行四边形diagonal 对角线，斜的stamping冲压annealing退火welding焊接Generator stator and rotor parts发电机定转子部件Actuator motor执行器电机crane stator 起重机用电机定子Pressure-riveting压铆laminations for automobile motor汽车电机铁芯Synergy 协同cocking-up上翘EV Electron V olt电子伏特HEV Hybrid Electrical Vehicle混合动力汽车Hydraulic pump 液压驱动vibration free table减震桌Electric cabinet 电控柜barrier frequency截至频率Homogeneous primary windings 均匀的初级绕组Horizontal transmissibility 水平性传输resonance协振Elliptically rotation椭圆旋转angular velocity角速度A real time acquisition system实时采集系统phase control相差lead time投产前准备阶段interlocking咬合gluing粘合Clamping固定/夹紧burr毛边/铁屑anneal退火/韧炼Amortization分期偿还elongation延展力coax plug共轴插头Exciting current励磁电流software editor软件编辑器Hydraulic cylinder液压缸log files记录文件/日志文件Profilograph 轮廓曲线仪纵断面测绘仪表面光度仪Unloading problems卸货问题trolly货车/推车Communication protocol(计算机)通讯协议vacuum plate真空板Sucker吸盘torque force扭力vacuum pumps真空泵Bending machine 折床warranty guarantee授权保证Meeting minutes会议纪要rectangular/sinusoidal wave矩形波/正弦波magnetizing current励磁电流amplitude stability 放大稳定性The integral of the secondary voltage 次级电压的积分measuring gauge(n. 计量器；)测量仪Function generator信号发生器Using Wattmeter-Ammeter-V oltmeter Method用功率表/电流表/电压表ARCNET interface-card ARCNET网络接口卡等NO material无取向试样Magnetic displacement磁位移PO是指采购订单生产计划是依据客户的采购订单(客户PO)Ambit 范围/周围gauge测量器mechanical lifters机械升起装置connection screws螺钉连接solenoidn. [电] 螺线管；螺线形电导管control loop控制回路Higher Harmonics高次谐波DC Bias直流偏磁Higher centrifugal force高离心力control algorithm控制算法Ceramic陶瓷的strain gauge变形测量器Load cell称重传感器/测力传感器sample clamp样品夹G-clamp螺旋夹钳OD/ID(outside/inside diameter)外直径/内直径Sintered magnet烧结磁铁slot ripple线槽脉冲thermal demagnetization热退磁setup, commissioning (acceptance test)设定、命令（接收测试）operation of machine, Trouble shooting, calibration and adjustment and maintenance机器操作、问题处理、校正与调试维护radium半径Magnetic moment磁矩helmholtz coil 亥姆霍兹线圈。
一 磁场(magnetic field)
I B
I
X
B
半无限长载流长直导线的磁场 半无限长载流长直导线的磁场
π θ1 → 2 θ 2 →π
青岛科技大学
BP =
µ0I
4π r
I
o
r
* P
大学物理讲义
例2 圆形载流导线的磁场. 圆形载流导线的磁场 真空中 , 半径为R 的载流导线 , 通有电流I , 称圆 电流. 的磁感强度的方向和大小. 电流 求其轴线上一点 p 的磁感强度的方向和大小
大学物理讲义
z
青岛科技大学
带电粒子在磁场中沿 v 其他方向运动时 F 垂直 v 于 v 与特定直线所组成 的平面. 的平面 当带电粒子在磁场中 垂直于此特定直线运动时 受力最大. 受力最大 v v v
Fmax qv
v v v 将 大小与 q , v 无关 时，受力 Fmax ,将vFmax × v 方
3、7点 ：dB 、 点 +3
+
7
v Idl
R
6 5
青岛科技大学
=
µ 0 Id l
4π R
2
2、4、6、8 点 ： 、 、 、
+4
dB =
µ 0 Idl
4π R
sin 450 2
大学物理讲义
四
毕奥---萨伐尔定律应用举例 毕奥 萨伐尔定律应用举例 萨伐尔定律 载流长直导线的磁场. 例1 载流长直导线的磁场
B
π β1 = , β 2 = 0 2 1 B = µ 0 nI 2
µ0nI
x
大学物理讲义
1 µ 0 nI 2
O青岛科技大学z源自v Idlv' r
o
R
θ
大学英文版电磁学讲义1-9
9.2 Magnetization and Bound Currents 磁化和束缚电流
The volume density of bound current(束缚电流体密度): J x =∇ ×M x . The surface density of bound current(束缚电流面密度): K b x = M x × n . (9.13) (9.12)
J by =−∂ M z /∂ x .
. => J b =∇× M For M = M k Fig. 9.8.
K =M × n M= n m k
increasing in the Fig. 9.9 M z x k +x direction. The bound current is ∂M z J b =∇ × M=− j ∂x
9.4 Problems Involving Free Currents and Magnetic Materials 包含自由电流和磁介质的问题
Using Ampere's law of H, we can solve some problems in magnetic material with symmetry. Example 5: An infinite slab of a conducting material(无穷大导体平板) with magnetic susceptibility m carries a certain current distribution. The slab is parallel to the x y plane, between z = −a and z = a. It carries a free i . Above the x y plane the current volume current density J f z = J 0 z / a is out of the page, below it is into the page.
去太空旅行的具体方式英语作文
去太空旅行的具体方式英语作文Embarking on an Extraterrestrial Odyssey: A Comprehensive Guide to Space Travel.Since the dawn of humankind, the allure of space has captivated our imaginations, fueling dreams of venturing beyond the confines of our planet. While space travel was once relegated to the realm of science fiction, today, it stands as a tangible reality, offering unprecedented opportunities for exploration, scientific discovery, and human advancement.The Gateway to Space:Before embarking on an extraterrestrial journey, it is essential to ascend into the vacuum of space. Historically, this feat has been accomplished through the use of rockets, powerful engines that generate thrust by expelling propellant at high velocity.Modern rockets, such as the SpaceX Falcon 9 and the United Launch Alliance Atlas V, are capable of carrying payloads ranging from satellites to spacecraft into orbit around Earth. These vehicles typically utilize a multi-stage design, with each stage separating once its fuel is depleted, reducing weight and maximizing efficiency.Orbiting Our Celestial Abode:Once in orbit around Earth, spacecraft can take advantage of the planet's gravitational pull to maintain their altitude. This stable environment provides a platform for scientific research, spacewalks, and preparatory maneuvers for further space exploration.Venturing into Deep Space:Forays beyond Earth's orbit require additional propulsion systems. Chemical rockets, similar to those used for launch, can provide the necessary thrust for interplanetary travel. However, their limited efficiency restricts their range.Ion propulsion, a more efficient alternative, utilizes electrically charged ions to generate thrust. While ion engines produce less thrust than chemical rockets, they offer extended burn times, enabling spacecraft to travel vast distances over prolonged periods.Destination: Other Worlds.With propulsion systems at our disposal, we can set course for other planets and celestial bodies. Mars, with its potential for harboring life, stands as a primarytarget for human exploration. Spacecraft such as the Mars Exploration Rovers and the Curiosity rover have conducted extensive surveys of the Martian landscape, providing valuable insights into its geological features and search for signs of past or present life.Outer planets like Jupiter and Saturn offer tantalizing scientific mysteries. The Juno spacecraft currently orbits Jupiter, studying its enigmatic magnetic field and swirling atmosphere. Missions to Saturn have revealed breathtakingimages of its iconic rings and explored its enigmatic moons, including Titan with its methane lakes and thick atmosphere.Life in Space:Extended space travel poses unique challenges for human health and well-being. Astronauts experience microgravity, which can lead to bone and muscle loss, as well as physiological changes such as fluid shifts and cardiovascular adaptations.Spacecraft are designed with living quarters that provide a habitable environment for astronauts. These modules offer sleeping areas, sanitary facilities, and recreation spaces. Advanced life support systems regulate temperature, humidity, and air quality, ensuring the crew's health and safety.The Future of Space Travel:As technology advances, the possibilities for space travel expand. Reusable rockets, such as SpaceX's Falcon 9,significantly reduce launch costs, paving the way for more frequent and affordable access to space.Private space companies are also playing a growing role in space exploration. SpaceX, Blue Origin, and Virgin Galactic are developing spacecraft and launch systems that aim to make space travel more accessible and commercialize space-related activities.The International Space Station (ISS), an orbiting laboratory, serves as a hub for international cooperation and scientific research. Astronauts from various countries conduct experiments, collaborate on missions, and demonstrate the potential for long-term human habitation in space.The Promise of Space Exploration:Space travel holds immense promise for the advancement of humankind. It fuels scientific breakthroughs, fosters technological innovation, and inspires generations of scientists, engineers, and explorers. By venturing into thevast expanse beyond our planet, we not only expand our knowledge and capabilities but also contribute to the collective human legacy.The future of space travel is bright with endless possibilities. As we continue to push the boundaries of exploration, we can anticipate new discoveries, groundbreaking advancements, and the realization of our cosmic dreams.。
一 磁场magnetic field
青岛科技大学 大学物理讲义
0 I B 4 r0
2
1
. B 的方向沿 x 轴的负方向 电流 I 的指向与磁场 B 的方
向形成右手螺旋关系。
0 I sin d i （cos 2 cos 1 ） i 4 r0
z
D
2
无限长载流长直导线的磁场.
青岛科技大学 大学物理讲义
1）若线圈有 N 匝
（ 1） I （2 ）
R B x 0 I 0 o B0 2R
I
（ 4）
0 I BA 4π d
d *A
R1 R2
R
o （ 3） I R
B0
0 I
4R
（ 5） I
*o
B0
o
0 I
8R
B0
0 I
4 R2
0 I
4 R1
大学物理讲义
y R cos z R sin
青岛科技大学
r xi R cos j sin k dl R sin j cos k 0 IR dB sin j cos k 3 4 r xi R cos j sin k d 0 IR Ri x cos j x sin k d 3 4 r 2 0 IR 线圈电流 I 的指向与磁场 B 的方 B i 3 向形成右手螺旋关系。 2 2 2 2 （x R ）
7 2 真空磁导率0 4π 10 N A
r
(magnetic permeability)
任意载流导线在点 P 处的磁感强度
磁感强度叠加原理
Understanding the Properties of Magnetic Materials
Understanding the Properties ofMagnetic MaterialsMagnetic materials have fascinated humans for centuries. From the mysterious lodestone that could attract iron to modern-day magnets used in a wide range of applications, magnetic materials have found their way into our daily lives. Understanding the properties of magnetic materials is essential for developing new applications and improving existing ones. In this article, we will explore the fundamental properties of magnetic materials and their relevance in various fields.Let us start with the basics. Magnetic materials are materials that are capable of generating a magnetic field. They can be classified into two categories: ferromagnetic and paramagnetic materials. Ferromagnetic materials, such as iron, cobalt, and nickel, exhibit a strong magnetic field, even in the absence of an external magnetic field. They also retain their magnetization even after the external field is removed. On the other hand, paramagnetic materials, such as aluminum, copper, and platinum, exhibit a weak magnetic field when exposed to an external magnetic field. However, they do not retain any magnetization once the external field is removed.Magnetic materials exhibit a unique property known as hysteresis. Hysteresis refers to the phenomenon in which the magnetic properties of a material depend on the history of magnetic fields it has been exposed to. The hysteresis curve represents the magnetization of the material as a function of the applied magnetic field. The area enclosed by the hysteresis curve represents the energy losses within the material. This phenomenon is important in the development of magnetic materials for power applications such as motors and transformers.The properties of magnetic materials are also affected by temperature. The degree of magnetization of ferromagnetic materials decreases as the temperature increases above a critical temperature known as the Curie temperature. Above this temperature, ferromagnetic materials become paramagnetic. The Curie temperature also plays a crucialrole in the development of magnetic materials for data storage applications such as magnetic tapes and hard disks.Another significant property of magnetic materials is their magnetic anisotropy. Magnetic anisotropy refers to the directionality of the magnetic properties of a material. The magnetic anisotropy of a material can be induced by an external magnetic field, uniaxial stress, or crystallographic structure. Magnetic anisotropy plays a crucial role in the development of magnetic materials for applications such as magnetic data storage, magnetic sensors, and magnetic actuators.The magnetic properties of materials can be controlled by manipulating their crystallographic structure. The crystallographic structure of a material affects the magnetic properties due to the interaction of electrons and the crystal lattice. The properties of magnetic materials can also be influenced by introducing impurities or alloys into the material. This process is known as doping and is commonly used to improve the magnetic properties of materials for various applications.In conclusion, understanding the properties of magnetic materials is critical for developing new technologies and improving existing ones. The fundamental properties of magnetic materials such as hysteresis, magnetic anisotropy, and temperature dependence are essential in the development of magnetic materials for various applications. The manipulation of crystallographic structure, the introduction of impurities and alloys, and other techniques have enabled researchers to improve the magnetic properties of materials for specific applications. With the continued development of magnetic materials, we can look forward to new and improved technologies that will enhance our daily lives.。
磁铁吸力 英语
IntroductionMagnetic attraction, an intriguing and fundamental phenomenon in the realm of physics, is a powerful force that arises between magnets or magnetic materials due to their intrinsic magnetic fields. This force, which underpins numerous technological applications and scientific advancements, is governed by intricate principles that extend beyond simple binary attraction or repulsion. This comprehensive analysis delves into the multifaceted nature of magnetic attraction, examining its underlying principles, factors influencing its strength, its manifestations across various scales, and its profound impact on modern technology and scientific research.I. Fundamentals of Magnetic Attraction: The Role of Magnetic Fields and PolesAt the heart of magnetic attraction lies the concept of magnetic fields, generated by moving electric charges or the inherent arrangement of electrons within atoms. A magnet possesses a north (N) pole and a south (S) pole, with the magnetic field lines emerging from the N-pole and terminating at the S-pole. According to Coulomb's law for magnetic forces, like poles repel each other, while unlike poles attract, giving rise to the familiar behavior of magnets attracting or repelling each other depending on their relative orientations.The strength of magnetic attraction between two magnets is determined by several factors, including:1. **Magnetic Moment**: This quantifies the magnet's overall magnetic strength, proportional to the product of its pole strength and the distance between the poles (magnetic length). A larger magnetic moment translates to a stronger magnetic force.2. **Distance**: Magnetic attraction follows an inverse square law, meaning that as the distance between two magnets increases, the attractive force decreases proportionally to the square of the distance. This is mathematically expressed as F ∝ (magnetic moment of magnet 1 × magnetic moment of magnet 2) / (4π× distance^2 × permeability of the medium).3. **Orientation**: The angle between the magnetic moments of the interacting magnets significantly affects the net attractive force. When the magnetic moments are aligned, the force is maximized; when they are orthogonal, the force is zero.4. **Magnetic Permeability**: The ease with which a material allows magnetic flux to pass through it influences the strength of magnetic interactions. Materials with high permeability, such as iron, enhance magnetic attraction, whereas non-magnetic substances like air or vacuum attenuate it.II. Manifestations of Magnetic Attraction Across Different ScalesA. Molecular and Atomic LevelAt the microscopic level, magnetic attraction is rooted in the quantum mechanical behavior of electrons within atoms. Unpaired electrons in certain elements, such as iron, cobalt, and nickel, possess intrinsic magnetic moments due to their spin and orbital motion. When these atoms align their magneticmoments cooperatively, they create a macroscopic magnetic field, giving rise to ferromagnetism, the strongest form of magnetism observed in nature.B. Macroscopic LevelIn everyday life, magnetic attraction is evident in various forms, from simple fridge magnets to complex industrial machinery. Permanent magnets, such as neodymium magnets, maintain a persistent magnetic field due to their stable internal magnetic structure, enabling strong and consistent magnetic attraction. Electromagnets, on the other hand, generate magnetic fields through the flow of electric current, allowing for controllable magnetic attraction.C. Cosmic ScaleMagnetic attraction also plays a significant role in astrophysical phenomena. Earth's magnetic field, generated by the motion of molten iron in its core, not only protects our planet from harmful solar radiation but also guides migrating animals and steers charged particles, creating stunning auroras. Similarly, magnetic fields in stars, galaxies, and even interstellar space influence the dynamics of celestial bodies and the behavior of plasma.III. Applications and Impact of Magnetic Attraction in Technology and ResearchA. Data StorageMagnetic attraction is crucial in modern data storage technologies, such as hard disk drives (HDDs) and magnetic tape. In HDDs, tiny magnetic domains on a spinning platter are polarized to represent digital bits, with the read/write head utilizing magnetic attraction to both record and retrieve data.B. Energy Generation and ConversionMagnetic attraction is central to the operation of electric generators and motors, where it converts mechanical energy to electrical energy and vice versa. In renewable energy systems like wind turbines and hydroelectric generators, the interaction between moving conductors and magnetic fields generates electricity.C. Medical ApplicationsMagnetic resonance imaging (MRI) relies on the interaction between magnetic fields and atomic nuclei, particularly hydrogen, to produce detailed images of internal body structures. Additionally, magnetic nanoparticles are being explored for targeted drug delivery and hyperthermia therapy in cancer treatment, exploiting magnetic attraction for precise localization and controlled release of therapeutic agents.D. Advanced Research and Emerging TechnologiesMagnetic levitation (maglev) trains employ magnetic attraction and repulsion to achieve frictionless movement and high speeds. Moreover, ongoing research in spintronics seeks to harness electron spin and magnetic interactions for novel electronic devices with enhanced functionality and energy efficiency.ConclusionMagnetic attraction, a seemingly simple yet profoundly intricate phenomenon, is governed by the interplay of magnetic fields, pole orientations,distance, and material properties. Its manifestations span across multiple scales, from atomic structures to cosmic phenomena, and have indelibly shaped the course of technological progress and scientific inquiry. As our understanding of magnetism deepens and new applications emerge, magnetic attraction will undoubtedly continue to play a pivotal role in driving innovation and advancing human knowledge.。
15544+自动化专业英语(习题参考解答)
自动化专业英语姜书艳主编张昌华徐心皓何芳编著习题参考解答Unit 1A. Basic laws of Electrical Networks[EX.1] Comprehension1. KCL:The algebraic sum of the currents entering any node is zero.KVL:The algebraic sum of the voltage around any closed path is zero.2. Node: A point at which two or more elements have a common connection is calleda node.Branches: a single path in a network composed of one simple element and the node at each end of that element.Path: If no node was encountered more than once, then the set of nodes and elements that we have passed through is defined as a path.Loop: If the node at which we started is the same as the node on which we ended, then the path is, by definition, a closed path or a loop. a path is a particular collection of branches.3. 4, 5, We can form a path but not a loop.4. v R2=32V, V x=6V[EX.2] Translation from English to Chinese1. 如果定义具有最大连接支路数的节点为参考节点，那么得到的方程相对来说比较简单。
介绍地球磁场的作文英文
介绍地球磁场的作文英文英文：The Earth's magnetic field is a fascinating and essential aspect of our planet. It plays a crucial role in protecting the Earth from harmful solar winds and cosmic radiation. The magnetic field is generated by the movement of molten iron and nickel in the Earth's outer core. This movement creates electric currents, which in turn produce a magnetic field. This field extends from the Earth'sinterior out into space and is often compared to a giant bar magnet.The Earth's magnetic field has a significant impact on our daily lives, although we may not always be aware of it. For example, it is the reason why a compass always points north. The magnetic field also affects the behavior of migratory birds and certain animal species that use it for navigation. Furthermore, it helps scientists understand the geological history of the Earth, as the magnetic mineralsin rocks align themselves with the Earth's magnetic fieldat the time of their formation.The magnetic field is not static and has undergone numerous reversals throughout Earth's history. These reversals, known as geomagnetic reversals, occur when the magnetic north and south poles switch places. This phenomenon has been studied by scientists, and the evidence of these reversals can be found in the ocean floor and in rocks.中文：地球的磁场是我们星球上一个迷人且至关重要的方面。
电磁场英文作文
电磁场英文作文English: Electromagnetic fields are a fundamental aspect of physics that encompass the combined electric and magnetic fields that permeate through space. These fields are generated by the movement of electrically charged particles, such as electrons, creating a force that can affect objects within the field. Electromagnetic fields play a crucial role in numerous phenomena, including light propagation, radio wave transmission, and the operation of electrical devices. Understanding electromagnetic fields is essential in various fields of science and technology, from designing electrical circuits to explaining the behavior of celestial bodies. Moreover, the study of electromagnetic fields has significant implications in our daily lives, such as in the development of new technologies and advancements in communication systems. Overall, the intricate interplay of electric and magnetic fields in electromagnetic phenomena highlights the fundamental nature of these fields in shaping the physical world around us.中文翻译: 电磁场是物理学中的一个基本方面，涵盖了贯穿空间的电场和磁场的结合。
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Magnetic field and Vacuum arc of new TMF-AMFcontactMin Li, Xiaoqin Wang, Wenyi Li, Shuping SunVacuum interrupter businessTianjin Pinggao Intelligent Electric Co., Ltd.Tianjin, ChinaE-mail: lim2013pg@Abstract—This paper introduces a new type TMF-AMF contact which used in high current interruption process. It has lower bulk resistance (3.28µΩ) of the conductive circuit compared with conventional one by introducing a 4 turn TMF coil and a 6 turn AMF coil. When the current is 1000A, the maximum value of B-field of radial TMF is 13.95mT, the maximum value of B-field of tangential TMF is 6.61mT, and the maximum value of B-field of AMF is 4.14mT. The maximum value of phase difference is 10.02°. The vacuum arc diffuses and turns between the contacts. The maximum value of vacuum arc voltage is 23.2V.Keywords—Vacuum interrupter; Magnetic field; Vacuum arc; ContactI.I NTRODUCTIONIn order to achieve excellent switching performance, there has been a continuous improvement in the vacuum interrupter contacts design. The contacts are separated at a current fault in an AC circuit; thereby a vacuum arc is created. Two standard methods are used for the vacuum arc control in order to improve the current interruption performance. One method is using a Transversal Magnetic Field (TMF) which can drive the constricted arc in rotational motion under the effect of Lorentz forces. The other method is generating an Axial Magnetic Field (AMF) so as to make the arc diffuse, with low current density over the whole contact surface [1]. Control the arc via AMF with all kinds of contact geometries has been routinely used especially in the interruption of large AC currents. The interruption performance of vacuum interruption is determined by axial B-field strength and its distribution.Because vacuum interruption contacts are normally kept in closed position for rated normal current condition, the total nominal resistance (contact and bulk resistance) of the contacts should be designed as low as possible. One of the primary drawbacks of the AMF contacts is their relatively large bulk resistance and contact resistance which is coming from the limitation on the closing forces [2]. In order to increase the mechanical strength of the contacts, a stainless-steel support is routinely added between the contacts and the cub sit. Some development work has been done by increasing the contacts cross-section and the coil thickness to reduce the contact`s bulk resistance without compromising the AMF performance, but this would result in a narrower effective AMF area and a big contact`s mass [3].The objective of this paper is to introduce a new type TMF-AMF contact that has lower resistance compared with conventional one. At the same time, its B-field strength can be kept. The B field simulation research was done in the previous work [4]. In this paper, the works focus on the experiment of B field and vacuum arc.II.N EW TYPE TMF-AMF CONTACTThe new type TMF-AMF contact is shown in Fig.1. It contains contact plate, 4 turn TMF coil, stainless steel support, 6 turn AMF coil and conducting rod. The diameter of the contact is 70mm. The new TMF-AMF concept was investigated theoretically regarding its potential for high current interruption. To elucidate the potential and feasibility of the new TMF-AMF contacts, the bulk resistance simulation was carried out by software. The bulk resistance simulationmodel is shown in Fig.2.Fig.1 New type TMF-AMF contact2015 3rd International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) Oct. 25-28, 2015 Busan, KoreaFig.2 The bulk resistance simulation modelIII. T HE EXPERIMENT METHODThe test diagram of B-field strength is shown in Fig.3. In order to form a current circuit, a copper cylinder was put on the contacts. This was used to simulate the vacuum arc between contacts. The diameter of the copper cylinder was 10mm, and it`s height was 8mm. When the power switch was closed, the current will flow from one contact to the other contact. The peak value of current was 1000A. Fig.4 shows the test picture of B-field strength. In order to exactly measure the distribution of B field in the gap of contacts, the contact was averagely divided to 8 parts. The hall sensor prober was put in the middle of the contacts gap. The measured points clockwise turned 45°, 90°, 135°, 180°, 225°, 270°, 315°respectively from copper cylinder. When measured the alternate B field, the voltage signal of tesla meter was amplitude modulated wave. A no inductive current divider was installed in series; the voltage signal of the two terminals of the current divider was direct ratio to circuit current. Both output signal of current divider and tesla meter imported oscilloscope, the amplitude of B field and the phase relationship between B field and circuit current were got from the two waveforms.Fig.3. The test diagram of B-field strengthFig.4. The test picture of B-field strengthIn order to research the control effect of B field on vacuum arc, the drive arc experiment was done in detachable vacuum interrupter. The vacuum arc image was got by high speed CCD camera. The effective value of experiment current is 20kA.IV. S IMULATION AND EXPERIMENTAL RESULTS The simulation results show that the bulk resistance of the conductive circuit is 3.28µΩ. It is much lower than that of conventional ones.The typical alternate B field was shown in Fig.5. The phase relationship between current and B field can be got from it.Fig.5 Typical alternate B fieldThe peak value of tangential TMF at measured points is shown in Fig.6. It can be seen that the peak value of tangential TMF firstly increases and then decreases with the measure angle increases. The maximum value is 6.61mT at 225°.P e a k v a l u e o f t a n g e n t i a l T M F (m T )Measured point (o)Fig.6 The peak value of tangential TMF at measured pointsThe peak value of radial TMF at measured points is shown in Fig.7. The peak value of radial TMF firstly decreases and then increases with the measure angle increases. The maximum value is 13.95mT at 315°. It can be seen that the peak value of radial TMF is bigger than that of tangential TMF. The radial TMF will drive the arc rotary motion on the contacts.P e a k v a l u e o f r a d i a l T M F (m T )Measured point (o)Fig.7 The peak value of radial TMF at measured pointsFig.8 shows the peak value of AMF at measured position. The measured positions are 0mm, 5mm and 10mm from the inner edge of contact at 90°, 180° and 270°. The peak value of AMF firstly increases and then decreases with the measure distance increases, and the maximum value appears at 5mm. The peak value of AMF firstly decreases and then increases with the measure angle increases, and the minimum value appears at 180°. The peak value of AMF at 90°is equal to that at 270°. The maximum value of AMF is 4.14mT.P e a k v a l u e o f A M F (m T )Measure position (mm)Fig.8 The peak value of AMF at measured positionThe phase difference between B filed and current is shown in Fig.9. The phase difference has little change with the distance increases. The phase differencefirstly decreases andthen increases with the measure angle increases. The maximum value of phase difference is 10.02°.P h a s e d i f f e r e n c e (o)Measure position (mm)Fig.9 The phase difference between B filed and currentThe arc voltage and current waveform of TMF-AMF are shown in Fig.10. The maximum arc voltage is 23.2V. The vacuum arc image of TMF-AMF is shown in Fig.11. It can be seen that the contacts begin to separate at 3.7ms. The vacuum arc is formed on the left side of contact; the arc voltage is about 17V. Another vacuum arc appears on the right side of contact, and then the size of arc gradually increases until 8ms. The size of arc on the left side of contact is obviously larger than that on the right side. After that, the acute degree of vacuum arc decreases with the current decreases. The size of vacuum arcs decrease and the vacuum arcs extinguish at 11ms. The open distance between contacts is about 6.8mm at this time. The vacuum arc has a rotation motion on the contact.-0.0050.0000.0050.0100.0150.020-100-80-60-40-2002040-100-80-60-40-2002040C u r r e n t (k A )A r c v o l t a g e (V )Time (s)Current Arc voltageFig.10 The arc voltage of TMF-AMF contactt=3.68ms d=0mm t=3.74ms d=0.125mmt=4ms d=0.25mm t=5ms d=1mmt=6ms d=1.75mm t=7ms d=2.5mmt=8ms d=3.5mm t=9ms d=4.625mmt=10ms d=5.625mmt=11ms d=6.75mmFig.11 The vacuum arc image of TMF-AMF contactThe surface image of TMF-AMF contact after vacuum arctest is shown in Fig.12. The left contact is anode and the rightcontact is cathode. It can be seen that there have two ablationpositions in the contact, one is bigger and the other is smaller.The bigger one is in the first vacuum arc position, and thesmaller one is in the second vacuum arc position. The ablationof the contact is slight. The first arc is diffuse on the contactand the second arc has a rotation on the contact.Fig.12 The surface image of TMF-AMF contact after vacuum arc testV.C ONCLUSIONSA new type TMF-AMF contact is introduced, which containscontact plate, 4 turn TMF coil, stainless steel support, 6 turnAMF coil. It has lower bulk resistance (3.28µΩ) of theconductive circuit compared with conventional one. This newtype contact is suitable for high current interruption process.The strength of TMF is higher than that of AMF. With themeasure angle increases, the peak value of tangential TMFfirstly increases and then decreases, the peak value of radialTMF firstly decreases and then increases; the peak value ofradial TMF is bigger than that of tangential TMF. The peakvalue and phase difference of AMF firstly decreases and thenincreases with the measure angle increases.When the current is 1000A, the maximum value of B-field ofradial TMF is 13.95mT, the maximum value of B-field oftangential TMF is 6.61mT, and the maximum value of B-fieldof AMF is 4.14mT. The maximum value of phase difference is10.02°. The vacuum arc diffuses and turns between thecontacts. The maximum value of vacuum arc voltage is 23.2V.The TMF will drive the arc in rotational motion toward theedge of contact plate. Meanwhile, the AMF will make the arcdiffuse.R EFERENCES[1] T. Lamara and D. Gentsch, High current vacuum arc investigation withnew innovative TMF-AMF contacts, XXVth Int. Symp. On Dischargesand Eletrical Insulation in Vacuum, Tomsk, 173-176, 2012.[2]P. G. Slade, M. The vacuum interrupter, theory, design and application,CRC press Taylor & Francis Group, 2008.[3]Z. Liu, Z. Wang and J. Wang, A new slot type axial magnetic fieldcontact with low resistance, XXIInd Int. Symp. On Discharges andElectrical Insulation in vacuum-Matsue, Japan, 2006.[4]Wenyi Li, Min Li, Xiaoqin Wang, et.al, Magnetic field simulationresearch of new TMF-AMF contacts, IEICE Technical Report, 2013,113(298): 221-224.。