Effect of a Magnetic Field on the Preparation of Silver Nanowires Using Solid Electrolyte Thin F

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物理学科常用单词

ensemble报错英[ɒn'sɒmb(ə)l]美[ɑn'sɑmbl]跟读口语练习∙n. 全体；总效果；全套服装；全套家具；合奏组∙adv. 同时∙oxide-assistant growth氧化物辅助生长penetration[pen·e·tra·tion || ‚penɪ'treɪʃn]n.穿透; 穿透深度; 穿透能力; 渗透electrode[e·lec·trode || ɪ'lektrəʊd]n.电极weak[wɪːk]adj.不牢固的, 虚弱的, 弱的trivial[ˈtriviəl]a.琐碎的，不重要的type[taɪp]n.类型, 模范, 典型hybrid['haibrid]n.混血儿, 杂种, 混合物a.混合的, 杂种的, 混合语的potential barrier penetration 势垒贯穿linear harmonic oscillator 线性谐振子zero proint energy 零点能Coulomb field 库仑场operator 算符angular momentum operator 角动量算符eigen value 本征值secular equation 久期方程dipole transition 偶极子跃迁filter[fil·ter || 'fɪltə(r)]n.过滤器, 用于分隔过滤的东西;v.过滤, 走漏, 渗透; 滤过; 走漏; 渗入thermionic[,θә:mi'ɒnik]a.热离子的[电]热离energy barrier2能障(能量位垒)trade off物物交换, 交换; 权衡, 让步parameter[pa·ram·e·ter || pə'ræmɪtə(r)]n.参数, 参量; 界限; 因素, 特征;external[ex'ter·nal || -nl]n.外部; 外面adj.外部的, 表面的, 客观的finite[fi·nite || 'faɪnaɪt]adj.有限的; 限定的; 有穷的an idealized quantum wirecomplementaryadj.补充的; 补足的seebeck coefficient[电]塞贝克系数generic[ge·ner·ic || dʒɪ'nerɪk]adj.属的; 一般的; 类的tuning[tun·ing || 'tuːnɪŋ/'tju-]n.调音, 调律, 调整coefficient[co·ef·fi·cient || ‚kəʊɪ'fɪʃnt]n.系数power factor[化]功率因数evaluate[e·val·u·ate || ɪ'væljʊeɪt]v.评估, 赋值, 评价open circuit[化]开路; 断路[医]断路, 切断电路operatinga.操作的, 工作的, 营业上的, 业务的, 关于收支的, 关于损益的, 外科手术的approach[əˈprəutʃ]v.靠近n.接近,临近;途径;方式,方法chemical potential化学势mechanism[mech·a·nism || 'mekənɪzm]n.机械, 结构, 机构be independent of temperature.compare our results across the three systems configuration[con·fig·u·ra·tion || kən‚fɪgjʊ'reɪʃn] n.结构; 形态; 表面配置; 行星的方位for simplicity为简单起见symmetrically[si'metikli]ad.匀称地, 对称地equilibrium[,i:kwi'libriәm]n.平衡, 平静, 均衡[化]平衡[医]平衡at equilibriumnonlinear operationnonlinear[ˈnɔnˈliniə]非线性; 非线性的; 非直线型的非线性运算division[di·vi·sion || dɪ'vɪʒn]n.区分, 分开, 除法; 部门magnetotransport磁运输measurement['meas·ure·ment || 'meʒə(r)mənt] n.测量法; 尺寸; 度量presence[pres·ence || 'prezns]n.出席, 存在, 到场the orbital motion of electrons电子轨道运动preserveda.喝醉的[计]保留的spin-orbit interaction[化]自旋轨道偶合interaction[ˌintəˈrækʃən]n.相互作用，相互影响fluctuation[fluc·tu·a·tion || ‚flʌktʃʊ'eɪʃn]n.波动; 动摇; 变动deduce[diˈdju:s]vt.推论，推断，演绎ground state基态first excited statea fixed number of electronspromising['prom·is·ing || 'prɑmɪsɪŋ/'prɒm-] adj.有希望的, 前途有望的spintronics自旋电子学effective mass[电]有效质量magnetic moment[化]磁矩concerning[con'cerning || -nɪŋ]prep.关于spin[spin]n.旋转, 自旋, 疾驰, 情绪低落fabrication[fab·ri·ca·tion || ‚fæbrɪ'keɪʃn] n.制作; 伪造物; 构成fabrication[fab·ri·ca·tion || ‚fæbrɪ'keɪʃn] n.制作; 伪造物; 构成epitaxial[ˏepɪˋtæksɪəl]外延的render[ˈrendə]vt.使得，致使；给予，提供；翻译magnetic field磁场spectrum[spec·trum || 'spektrəm]n.谱; 频谱; 光谱; 射频频谱the quenching of the orbital momentum轨道动量的淬灭quantum devices量子器件nanomaterialparticle[par·ti·cle || 'pɑrtɪkl /'pɑːt-]n.粒子, 极小量, 点A strongreduction in the effective electron or hole g factor toward 2 ultra[ul·tra || 'ʌltrə]adj.过度的, 极端的, 过激的heterostructure[ˏhetərəʊˋstrʌktʃə(r)]异晶结构; 异质结构exceed[ex·ceed || ɪk'siːd]v.超过, 胜过, 超越magnetic field splitting磁场劈裂complementaryadj.补充的; 补足的blockade[block·ade || blɒ'keɪd]n.封锁; 障碍物, 阻碍物; 道路阻塞v.封锁; 挡住; 阻塞chargestabilitydiagram电荷稳定性图conductance ridges电导脊fabricate['fab·ri·cate || 'fæbrɪkeɪt]v.制造; 伪造; 组装; 杜撰reactor[riˈæktə]n.反应堆aerosol['єәrәusɒl]n.烟, 雾[化]气溶胶; 烟雾剂diameter[di·am·e·ter || daɪ'æmɪtə]n.直径substraten.底层, 地层, 衬底, 基底, 基质, 酶作用物, 酶解物[计]衬底; 基片[化]反应物nucleation[化]成核作用with respect to关于，至于indiumn.铟antimony[an·ti·mo·ny || 'æntɪmənɪ]n.锑blende[blend]n.闪锌矿stacking faults,twin boundarieswithatomically flat {110}doped[dəupt]掺杂的; 掺杂过的thick[θɪk]adj.厚的, 浓的, 粗壮的adv.厚厚地; 浓浓地; 密集地; 强烈地capping layer覆盖层lithography[li'θɒgrәfi]n.平版印刷术electron beam.电子束etch[etʃ]v.蚀刻, 蚀镂; 施行蚀刻法solution[so·lu·tion || sə'luːʃn]n.解决, 溶液, 解答evaporation[e·vap·o·ra·tion || ɪ‚væpə'reɪʃn]n.蒸发; 消失; 发散rinse[rɪns]n.冲洗; 染发; 漂洗; 染发剂v.以清水冲洗, 漂清, 漱arebriefly etched in a (NH4)2S x solution followed by a rinse inH2Ofabricate['fab·ri·cate || 'fæbrɪkeɪt]v.制造; 伪造; 组装; 杜撰probe[prəʊb]n.探针, 探测针, 调查v.用探针测, 详细调查; 用探针探查, 探测; 调查; 查究probe station探针台cryostat['kraiәstæt]n.低温恒温器versus[ˈvə:səs]prep.以…为对手，对；与…相比之下source-drain voltageback gate voltage, V bgcontact separation[电]接触分离diamond-shaped[ˋdaɪəməndˋʃeɪpt]菱形even['i:vәn]a.平坦的, 相等的, 连贯的, 均等的, 公平的, 偶数的, 平均的, 平衡的, 恰好的vt.使平坦, 使相等vi.变平, 成为相等ad.甚至, 实际上, 完全, 十分odd[ɑd /ɒd]adj.奇数的, 剩余的, 古怪的alternate['ɒ:ltәnәt]a.交替的, 轮流的, 间隔的vt.轮流, (使)交替vi.轮流, (使)交替alternating交替的; 更迭的spin degeneracy[化]自旋简并性degeneracy[diˈdʒenərəsi]蜕化; 退化; 简并度; 简并性lateral[lat·er·al || 'lætərəl]n.侧部; 边音; 支线adj.侧面的, 旁边的oscillation[os·cil·la·tion || ɑsɪ'leɪʃn /ɒs-] n.摆动; 振动评击]wurtzite[ˈwəːtsait]纤维锌矿; 纤锌矿in thewurtzite phase,in the zinc blende phasedetachment[diˈtætʃmənt]after detachment from the growthsubstratequantized量子化的topological拓扑的helical[ˈhelikəl]螺线; 螺旋; 螺旋形plateau[ˈplætəu]n.高原；(上升后的)稳定时期(或状态)subband次能带spin−orbit coupling自选轨道耦合in the presence of a strong spin−orbit coupling由于一个强的自旋轨道耦合quasi['kwɑ:zi:]a.类似的, 准的computation[com·pu·ta·tion || ‚kɒmpjuː'teɪʃn]n.计算, 计量, 计数platform[plat·form || 'plætfɔrm /-fɔːm]n.月台, 坛, 讲台polarization[po·lar·i·za·tion || ‚pəʊləraɪ'zeɪʃn]n.产生极性; 偏振; 极化; 对立, 给予两个相反的倾向;hybrid[ˈhaibrid]桥接; 桥接岔路; 杂化; 杂种; 间生; 混合; 混合; 混合物; 混频环; 混杂的fulfillment[ful'fill·ment || fʊl'fɪlmənt]n.完成, 履行; 满足, 成就; 实现extent[ikˈstent]n.程度，范围，限度；广度，宽度，大小signature['signәtʃә]n.签字, 识别标志, 调号diffusive[di'fju:siv]a.散播的, 冗长的, 扩散的The formation of subbandsspin-degenerate自旋简并suppression[sup'pres·sion || sə'preʃn]n.压制; 禁止; 镇压; 抑制micrometer[mai'krɒmitә]n.测微计[医]微米imperfection[im·per·fec·tion || ‚ɪmpə(r)'fekʃn]n.不完美; 瑕疵; 缺点scatteringn.分散; 散落backscattering[ˋbækˏskætərɪŋ]geometry[ge'om·e·try || dʒɪ'ɑmɪtrɪ/-'ɒm-]n.几何学constriction[kәn'strikʃәn]n.压缩, 收缩, 紧压的感觉trajectory[trəˈdʒektəri]n.(抛射物)弹道轨道indication[in·di·ca·tion || ‚ɪndɪ'keɪʃn]n.指出; 迹象; 指示quasi['kwɑ:zi:]a.类似的, 准的spectroscopy[spek'trɒskәpi]n.光谱学lock(-)in同步intermediate[,in·ter'me·di·ate || ‚ɪntə(r)'mɪːdɪeɪtd] n.中间物, 调停者v.作中间人; 干预adj.中间的, 中级的fraction[frac·tion || 'frækʃn]n.分数, 破片, 小部分confirmation[con·fir·ma·tion || ‚kɒnfə'meɪʃn]n.证实, 批准, 巩固; 确认derivative[diˈrivətiv]变型; 导数; 从变量; 派生的; 派生物; 衍化物; 衍生物; 诱导剂The derivative of conductance to gate voltage电导对于栅电压的导数transconductance[计]跨导intersect[ˌintəˈsekt ; -ər-]交叉; 相交schematicallyadv.纲要性地; 图表式地pronounced[pro'nounced || prə'naʊnst]adj.显著的, 明白的, 断然的dominate['domi·nate || 'dɑmɪneɪt /'dɒm]v.支配, 控制, 统治; 高耸于dominated中等的; 中等木obscure[əbˈskjuə]a.不著名的；费解的vt.使变模糊，掩盖enabling observation of the 0.5g Qplateau for B ≥2 T and the 1.0g Q plateau for B ≥3 T.schematic[sche·mat·ic || skɪː'mætɪk]adj.概要的, 图解的macroscopic英[,mækrə(ʊ)'skɒpɪk]美[,mækrə'skɑpɪk]adj. 宏观的；肉眼可见的coherent transport line for microscopic quantum system 微观量子系统的相干输运过程intersection英[ɪntə'sekʃ(ə)n]美[,ɪntɚ'sɛkʃən]∙n. 交叉；十字路口；交集；交叉点The schematic of Ohm’s law of classical transport for macroscopic system 对于宏观系统经典输运欧姆定律的图解discharge英[dɪs'tʃɑːdʒ]美[dɪs'tʃɑrdʒ]∙vt. 解雇；卸下；放出；免除∙vi. 排放；卸货；流出∙n. 排放；卸货；解雇放电the microstructure evolution of silicon nanowires during the charge/discharge process as severing for the anodematerialforlithium-ion batteries;thecharge-dischargecharacteristic curves.充放电特征曲线锂电池充放电过程中硅纳米线作为阳极的演化规律anode英['ænəʊd]美['ænod]∙n. [电子] 阳极，[电] 正极。

磁学径向克尔英文 kerr effect

IntroductionThe Kerr effect, also known as the magneto-optic Kerr effect (MOKE), is a phenomenon that manifests the interaction between light and magnetic fields in a material. It is named after its discoverer, John Kerr, who observed this effect in 1877. The radial Kerr effect, specifically, refers to the variation in polarization state of light upon reflection from a magnetized surface, where the change occurs radially with respect to the magnetization direction. This unique aspect of the Kerr effect has significant implications in various scientific disciplines, including condensed matter physics, materials science, and optoelectronics. This paper presents a comprehensive, multifaceted analysis of the radial Kerr effect, delving into its underlying principles, experimental techniques, applications, and ongoing research directions.I. Theoretical Foundations of the Radial Kerr EffectA. Basic PrinciplesThe radial Kerr effect arises due to the anisotropic nature of the refractive index of a ferromagnetic or ferrimagnetic material when subjected to an external magnetic field. When linearly polarized light impinges on such a magnetized surface, the reflected beam experiences a change in its polarization state, which is characterized by a rotation of the plane of polarization and/or a change in ellipticity. This alteration is radially dependent on the orientation of the magnetization vector relative to the incident light's plane of incidence. The radial Kerr effect is fundamentally governed by the Faraday-Kerr law, which describes the relationship between the change in polarization angle (ΔθK) and the applied magnetic field (H):ΔθK = nHKVwhere n is the sample's refractive index, H is the magnetic field strength, K is the Kerr constant, and V is the Verdet constant, which depends on the wavelength of the incident light and the magnetic properties of the material.B. Microscopic MechanismsAt the microscopic level, the radial Kerr effect can be attributed to twoprimary mechanisms: the spin-orbit interaction and the exchange interaction. The spin-orbit interaction arises from the coupling between the electron's spin and its orbital motion in the presence of an electric field gradient, leading to a magnetic-field-dependent modification of the electron density distribution and, consequently, the refractive index. The exchange interaction, on the other hand, influences the Kerr effect through its role in determining the magnetic structure and the alignment of magnetic moments within the material.C. Material DependenceThe magnitude and sign of the radial Kerr effect are highly dependent on the magnetic and optical properties of the material under investigation. Ferromagnetic and ferrimagnetic materials generally exhibit larger Kerr rotations due to their strong net magnetization. Additionally, the effect is sensitive to factors such as crystal structure, chemical composition, and doping levels, making it a valuable tool for studying the magnetic and electronic structure of complex materials.II. Experimental Techniques for Measuring the Radial Kerr EffectA. MOKE SetupA typical MOKE setup consists of a light source, polarizers, a magnetized sample, and a detector. In the case of radial Kerr measurements, the sample is usually magnetized along a radial direction, and the incident light is either p-polarized (electric field parallel to the plane of incidence) or s-polarized (electric field perpendicular to the plane of incidence). By monitoring the change in the polarization state of the reflected light as a function of the applied magnetic field, the radial Kerr effect can be quantified.B. Advanced MOKE TechniquesSeveral advanced MOKE techniques have been developed to enhance the sensitivity and specificity of radial Kerr effect measurements. These include polar MOKE, longitudinal MOKE, and polarizing neutron reflectometry, each tailored to probe different aspects of the magnetic structure and dynamics. Moreover, time-resolved MOKE setups enable the study of ultrafast magneticphenomena, such as spin dynamics and all-optical switching, by employing pulsed laser sources and high-speed detection systems.III. Applications of the Radial Kerr EffectA. Magnetic Domain Imaging and CharacterizationThe radial Kerr effect plays a crucial role in visualizing and analyzing magnetic domains in ferromagnetic and ferrimagnetic materials. By raster-scanning a focused laser beam over the sample surface while monitoring the Kerr signal, high-resolution maps of domain patterns, domain wall structures, and magnetic domain evolution can be obtained. This information is vital for understanding the fundamental mechanisms governing magnetic behavior and optimizing the performance of magnetic devices.B. Magnetometry and SensingDue to its sensitivity to both the magnitude and direction of the magnetic field, the radial Kerr effect finds applications in magnetometry and sensing technologies. MOKE-based sensors offer high spatial resolution, non-destructive testing capabilities, and compatibility with various sample geometries, making them suitable for applications ranging from magnetic storage media characterization to biomedical imaging.C. Spintronics and MagnonicsThe radial Kerr effect is instrumental in investigating spintronic and magnonic phenomena, where the manipulation and control of spin degrees of freedom in solids are exploited for novel device concepts. For instance, it can be used to study spin-wave propagation, spin-transfer torque effects, and all-optical magnetic switching, which are key elements in the development of spintronic memory, logic devices, and magnonic circuits.IV. Current Research Directions and Future PerspectivesA. Advanced Materials and NanostructuresOngoing research in the field focuses on exploring the radial Kerr effect in novel magnetic materials, such as multiferroics, topological magnets, and magnetic thin films and nanostructures. These studies aim to uncover newmagnetooptical phenomena, understand the interplay between magnetic, electric, and structural order parameters, and develop materials with tailored Kerr responses for next-generation optoelectronic and spintronic applications.B. Ultrafast Magnetism and Spin DynamicsThe advent of femtosecond laser technology has enabled researchers to investigate the radial Kerr effect on ultrafast timescales, revealing fascinating insights into the fundamental processes governing magnetic relaxation, spin precession, and all-optical manipulation of magnetic order. Future work in this area promises to deepen our understanding of ultrafast magnetism and pave the way for the development of ultrafast magnetic switches and memories.C. Quantum Information ProcessingRecent studies have demonstrated the potential of the radial Kerr effect in quantum information processing applications. For example, the manipulation of single spins in solid-state systems using the radial Kerr effect could lead to the realization of scalable, robust quantum bits (qubits) and quantum communication protocols. Further exploration in this direction may open up new avenues for quantum computing and cryptography.ConclusionThe radial Kerr effect, a manifestation of the intricate interplay between light and magnetism, offers a powerful and versatile platform for probing the magnetic properties and dynamics of materials. Its profound impact on various scientific disciplines, coupled with ongoing advancements in experimental techniques and materials engineering, underscores the continued importance of this phenomenon in shaping our understanding of magnetism and driving technological innovations in optoelectronics, spintronics, and quantum information processing. As research in these fields progresses, the radial Kerr effect will undoubtedly continue to serve as a cornerstone for unraveling the mysteries of magnetic materials and harnessing their potential for transformative technologies.。

磁共振成像常用技术术语

absolute intensityA display or plot mode in which the signal intensity is proportional to theacquisition timeattenuationThe control applied to voltages (including signal from the sample) within the spectrometer. High attenuation gives low-voltage, low-attenuation gives high-voltage.B 0The static magnetic field. The magnetic flux density is expressed in tesla,T, or often, as an equivalent 1H resonance frequency (for example, 300MHz for a 7 T magnet).B 1Magnetic field associated with a radio-frequency (r.f.) pulse. Often expressed as an equivalent value in kHz.bandshapeUsually used when referring to a complex lineshape or a group of overlapping plex bandshapes often arise from quadrupolar nuclei (see figure 2).centrebandThe signal at the isotropic chemical shift. Its position is the same at all spin-rates.channelThe individual frequencies or frequency bands of a spectrometer. For example: H-channel (proton), C-channel (carbon) or broad-band (or X) channel (usually anything except H).chemical shiftNumber used for reporting the position of a line (νi )relative to a reference line (νref ) in a high-resolution spectrum. The chemical shift parameter is denoted δ and quoted in ppm.coherence pathwayDescription of an experiment that allows the excitation of the spins to be followed. Useful for experiments where excitation or selection of signal from one-, two- or multiple-quantum transitions is needed.contact timeTime during which two matched radio-frequency fields are applied simultaneously in a CP experiment.CPCross-polarisation. Any experiment where energy (magnetisation) is transferred from the nuclei of one element (often H) to those of another.dead-time Time between a pulse and the switch on of the receiver. The spectrometercircuitry needs time to settle after transmitting the high voltage associatedwith a pulse before it can detect the very low voltage associated with thesignal from the sample. See figure 1.610×−=ref ref i νννδTerminology Commonly Used in NMR SpectroscopyFigure 2. Bandshape from a single 11B environment.磁共振成像常用技术术语d.c. offset Constant-value offset occurring in the FID (see “Problems”). Results ina central (zero-frequency) “spike” artefact in the spectrum whentransformed.deconvolution Mathematical process used to determine the intensities of overlappinglines.digital resolution This depends on the Fourier number. The bigger the Fourier number thegreater the number of data points per Hz of the spectrum and the higherthe digital resolution. See “Processing”.DP Direct-polarisation. An experiment in which the nuclei to be observedare excited directly.duty cycle A value used to assess whether anexperiment might damage thespectrometer (or the sample). Theduty cycle should never exceed 20 %(see “How to Choose a RecycleDelay”)dwell Spacing between data points in the time-domain. Can depend on theway acquisition is implemented but, commonly, dwell = 1/spectral width. endcap Open rotors have to be closed with endcaps before they can be spun. FID Free Induction Decay (see figure 1).field Magnetic field, with flux density quoted in T (Tesla) for the static magneticfield (B). For the magnetic field associated with an r.f. pulse the fluxdensity is given in mT or, more usually, expressed as a kHz equivalent(see “Matching”).flip-back Experimental procedure for shortening recycle times (see “How to Choosea Recycle”).Fourier number The number of points used in the FT. Always a power of 2.frequency domain Where information is displayed as a function of frequency - the spectrum FT Fourier Transform. Mathematical process to convert time-domain tofrequency-domain. Designed to work with 2n (n = integer) data points. gain Amplification applied to the received signal.Gauss Non-SI unit of magnetic field flux density. The SI equivalent is Tesla (T),1 T = 10,000 Gintensity On its own - the height of a line. Integrated-intensity is the area under theline.linebroadening Spectra can be artificially linebroadened to improve their appearance.This involves multiplying the FID with a decaying function prior to the FT.See “Processing”.lineshape The shape of individual lines in a spectrum. Commonly, Gaussian orLorentzian (figure 3) or a mixture of the two, are encounteredexperimentally.linewidth This is usually the full width at half-height (δν½)r.f. on-timer.f. on-time + r.f. off-timeduty cycle =magic-angle54.7° or 54° 44´magnetisation when described classically (non-quantum mechanically) an ensemble ofspins at equilibrium in an external magnetic field has a net magnetisationprecessing about an axis aligned along that field.magnetogyric ratio Symbol γ . A fundamental physical constant of elements with non-zerospin. For example γH is 2.675x108 rads -1T -1.matchShort for Hartmann-Hahn match (see “Matching”)noisenormalised intensity Signal intensity can be multiplied by an arbitrary factor to give a particularheight to the highest (often) line or the integrated intensity. Opposite ofabsolute intensity.nuclear spin quantum number Symbol I . A fundamental property of a nucleus. Only nuclei with I > 0are said to be NMR “active”.phase (1)The phase of a pulse relates to its position in the xy plane of the rotating frame.phase (2)The phase of a spectral line comes from the way in which the real and imaginary components of a complex FT are combined (see “Processing”).phase cycling The way in which the phase of a pulse (or the receiver) is changed duringsuccessive repetitions of a pulse sequence. Used to suppress artefactsand select specific coherence pathways.ppm Parts per million. Usual way of reporting a chemical shift. A frequencydifference ∆ Hz 610×∆≈n observatio ν ppm precession“Movement of the axis of a spinning body around another axis” (as a gyroscope)probeThe business end of the spectrometer, where the sample goes.pulse angle When described in the rotating frame a pulse rotates the magnetisationthrough an angle θ. A pulse that rotates the magnetisation though 90° iscalled a 90° pulse.pulse duration Time for which a pulse occurs.quadrupole Any nucleus with I > ½.recycle (time)Or pulse delay or relaxation delay. Time between the end of dataacquisition and the start of excitation in successive repetitions of a pulsesequence. (See “How to Choose a Recycle”).referenceThe material giving the signal which defines the zero position in a high-heightresolution spectrum.repetitionsThe number of times a pulse sequence is repeated in an experiment.resolutionThe ability to separate closely spaced lines (see figure 4). As a rule of thumb,a pair of lines will be resolved if their linewidth is less than their separation.resolution enhancementThe opposite of linebroadening. An FID multiplied by an appropriate combination of increasing and decaying functions can yield extra resolution in a spectrum. See “Processing”.rotary echoA feature of an FID that occurs at intervals of 1/spin-rate (see “How to Set the Magic-angle”). They give rise to spinning sidebands in the spectrum.rotating frameA mathematical tool to make the effect of a pulse easy to visualise.Magnetisation precessing at ν Hz in a laboratory-based xyz axis system appears static in an axis system (frame) rotating at ν Hz.rotorThe container that holds the sample. Often referred to in terms of its outside diameter (for example, 5 mm).saturationCondition that arises when there is no population difference between excited and ground states. No signal is observable under such conditions.sidebandsOr spinning sidebands. Under some circumstances sidebands appear in a spectrum. They can occur on both sides of a centreband and separated from it by a frequency equal to the spin-rate. A spectrum may contain a manifold of sidebands and the centreband is not necessarily more intense than all of the sidebands.signalThe FID or one or more of the lines in a spectrum.signal-to-noise ratio (S/N)Ratio of the height of a line or signal (usually the largest) to the noise.Definitions of the measurement of noise vary. Signal increases as n (the number of repetitions) but noise only increases by √n so S/N increases by √n.spectral widthDifference in frequency of the two ends of the full spectrum. Not to be confused with the now largely obsolete term sweep width.spinA property of a nucleus with non-zero nuclear spin-quantum number (I ),as in spin-½. Or, simply, a nucleus with a magnetic moment.spin-lockIf, after a 90°x pulse a second, long-duration (spin-lock) r.f. field is applied along the y-axis the magnetisation is said to be spin-locked.spin-rateThe rate at which the sample is spun.spin-temperature inversionA manipulation carried out within the phase cycling of a CP experiment to remove magnetisation originating directly from the X-channel contact pulse.standard Any sample used to set-up the spectrometer and/or to define the zeroposition in the spectrum.Figure 4. Two lines of constant spacing but different linewidth.T 1Spin-lattice relaxation time-constant. Relates to the time taken for excited spins, in the presence of B 0, to loose energy to their surroundings and return to their equilibrium state.T 1ρSpin-lattice relaxation time-constant in the rotating frame. As for T 1 but this time in the presence of an applied radio-frequency field B 1.T 2Spin-spin relaxation time-constant. Relates to the time for a conserved exchange of energy between spins.T 2*A time-constant sometimes used to describe the decay of the observed time-domain signal (T 2* ≤ T 2). The shorter T 2* the broader the associated signal(s) in the spectrum.time-domainWhere information is recorded or displayed as a function of time (see figure 1).transmitter offsetThis allows fine control of the position of a transmitter (carrier frequency).With an appropriate offset, signals can be put exactly on-resonance or a specific amount off-resonance. Can be applied to any spectrometer channel.truncationIf the acquisition time is shorter than the FID then truncation of the FID is said to have occurred (See “Problems”).zero filling If the number of data points is not a power of two then zeroes are addedto the acquired data so that the total number of points Fourier transformedis 2n . Zero filling adds no signal to the spectrum but it can improveresolution (see “Processing”).。

外研版选修八单词

adj.
磁的，磁性的，磁场的
(SH8 M1)
glare
/gleə/
n.
刺眼的光
(SH8 M1)
intense
/ɪn'tens/
adj.
强烈的
(SH8 M1)
sunglasses
/'sʌn,glɑ:siz/
n.
太阳镜；墨镜
(SH8 M1)
sun cream
n.
防晒霜
(SH8 M1)
severe
/ sɪ'vɪə/
n.
地衣
(SH8 M1)
adapt to
〔使〕适应
(SH8 M1)
trap
/træp/
v.
储存，留存
(SH8 M1)
meteorite
/'mi:tɪə‚raɪt/
n.
陨石
(SH8 M1)
extraterrestrial
/,ekstrətə'restrɪəl/
adj.
天外的，地球外的
(SH8 M1)
mass
trader
/'treɪdə/
n.
商人；买卖人；经商者
(SH8 M1)
spice
/spaɪs/
n.
香料
(SH8 M1)
jewel
/'dʒu:əl/
n.
宝石
(SH8 M1)
befriend
/bɪ'frend/
v.
对待……如朋友
(SH8 M1)
tale
/teɪl/
n.
传说；故事
(SH8 M1)
legendary
seek

科英写作Inversion, omission and discountious modificaiton

Fig. 5-1. 3. 所谓线性工作指的是放大器能够以很小的失真或无失
真地放大信号的能力。 4. 万一发生什么情况，请立即告诉我们。
By linear operation is meant the ability of an amplifier to amplify a signal with little or no distortion. Should anything happen, let us know as soon as possible.
西安电子科技大学
Ⅱ . Ellipsis in adverbial clauses
1. common pattern
adj.
it is conj. + they are +
p. p. prep. phrase
n.
When pure, water is a colorless liquid.
金属受热就会膨胀
Shown in Fig. 8 is a block diagram of a digital computer.
西安电子科技大学
4. prep. Phrase/引导词there + passive voice + S “所谓 ···指的是” :By A i和。
如果知道角度，不仅可以求出函数值；而且若知道函数值，也能求出角来。
Not only are we able to find values of the functions if we know the angle, but also we can find the angle if we know the value of a function.
西安电子科技大学

四大发明英文版

Consequences
Especially during the Ming Dynasty, Zheng He made expeditions to Southeast Asia for seven times with more than 27000 people and dozens of big ships each time, which contributes to the extension and development of seafaring and foreign trade in the world
Importance
From simply using it to find direction and judge fengshui to magnetic compass being used in world navigation, till today, various newly-invented magnetic compasses are applied broadly.
By CAI lun in eastern han dynasty (105) of the first year of yuan xing papermaking, improved by CAI lun in the bark, hemp heads and our raw materials such as cloth, fishing nets, after falling, dao, copy paper, drying technology, manufacturing, is the origin of modern paper. This paper, the raw material is easy to find and very cheap, quality is also improved, gradually widely used. In honour of the feat, CAI lun later generations called this paper "Cai Hou paper"

微波消解-电感耦合等离子体原子发射光谱法测定铁硅铝磁芯中铝和硅

微波消解-电感耦合等离子体原子发射光谱法测定铁硅铝磁芯中铝和硅吴永明;陶武;杨倩倩;杜效;王继龙;郭飞飞【摘要】使用盐酸-硝酸-氢氟酸并采用微波消解法处理样品,选择Al 308.215 nm 和Si 212.412 nm作为分析线,基体匹配法配制标准溶液系列绘制校准曲线,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定铝和硅,从而建立了微波消解-电感耦合等离子体原子发射光谱法(ICP-AES)测定铁硅铝磁芯中铝和硅的方法.结果表明,铝和硅的质量分数分别为1.00%~9.00%和2.50%~12.50%时与其发射强度呈线性,线性相关系数均不小于0.999 4;方法中铝和硅的检出限分别为0.020%和0.021%(质量分数).实验方法应用于铁硅铝磁芯样品中铝和硅的测定,结果的相对标准偏差(RSD,n=6)为1.4%~2.2%;将测定结果与滴定法(测定铝)和重量法(测定硅)的测定结果进行比对,二者相吻合.%The sample was treated in hydrochloric acid-nitric acid-hydrofluoric acid system by microwave digestion method.Al 308.215 nm and Si 212.412 nm were selected as the analytical lines.The standard solution series were prepared by matrix matching method to plot the calibration curve.The contents of aluminum and silicon were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES).Consequently, a determination method of aluminum and silicon in iron-silicon-aluminum magnetic core was established by ICP-AES with microwave digestion.The results showed that the mass fraction of aluminum and silicon in range of 1.00%-9.00% and 2.50%-12.50% were linear to their corresponding emission intensity, respectively.The linear correlation coefficients were not lower than 0.9994.The detection limit of aluminum and silicon was 0.020% and 0.021% (mass fraction), respectively.The proposed method was applied to the determination of aluminum and silicon in iron-silicon-aluminum magnetic core samples.The relative standard deviations (RSD, n=6) were between 1.4% and 2.2%.The results were consistent with those obtained by titrametry (for aluminum) and gravimetry (for silicon).【期刊名称】《冶金分析》【年(卷),期】2017(037)006【总页数】6页(P69-74)【关键词】微波消解;电感耦合等离子体原子发射光谱法(ICP-AES);铁硅铝磁芯;铝;硅【作者】吴永明;陶武;杨倩倩;杜效;王继龙;郭飞飞【作者单位】北京科技大学化学分析中心,北京 100083;北京科技大学化学分析中心,北京 100083;钢铁研究总院,北京 100094;钢铁研究总院,北京 100094;钢铁研究总院,北京 100094;钢铁研究总院,北京 100094【正文语种】中文随着电子技术的迅猛发展，电子产业对电子器件的高频化、高功率密度化、小型化及抗电磁干扰的要求日益突出，市场需求日益增加。

化学共沉淀法制备纳米四氧化三铁粒子.

第29卷第1期2007年3月湖北大学学报(自然科学版Journal of Hubei University (Natural ScienceVol.29No.1Mar.,2007收稿日期:20060622作者简介:黄菁菁(1981,女,硕士生文章编号:10002375(200701005003化学共沉淀法制备纳米四氧化三铁粒子黄菁菁,徐祖顺,易昌凤(湖北大学材料科学与工程学院,湖北武汉430062摘要:用化学共沉淀法制备纳米四氧化三铁粒子,应用X 射线衍射,透射电子显微镜对磁性粒子的结构、粒径、形貌进行了表征,并讨论铁盐溶液浓度、沉淀剂浓度及超声波对粒子粒径的影响.关键词:化学共沉淀法;四氧化三铁;超声波中图分类号:TM227,O611.4文献标志码:A随着纳米技术的发展,有关磁性纳米粒子的制备方法及性质受到极大的重视.四氧化三铁纳米粒子在作为磁记录材料、磁流体的基本材料、特殊催化剂原料、功能材料和磁性颜料等方面显示出许多特殊的功能[1~5].目前,制备纳米四氧化三铁的方法有很多,如水热反应法[6],中和沉淀法[7],化学共沉淀法[8],沉淀氧化法[9],r -ray 辐照法[10],微波辐射法[11]等,其中以共沉淀法最为简便.本实验采用化学共沉淀法制备纳米Fe 3O 4粒子,并讨论了铁盐浓度、沉淀剂浓度以及超声波对微粒粒径的影响.1实验部分1.1试剂及仪器FeCl 3・6H 2O (AR ;FeSO 4・7H 2O (AR ;N H 3・H 2O (AR ;S K2200H 型超声波发生器,频率20k Hz ,功率90W ;D/MAX 2ⅢC 型X 射线扫描仪(XRD ;TEX 2100SX 型透射电子显微镜(TEM .1.2实验原理将二价铁盐(FeSO 4・7H 2O 和三价铁盐(FeCl 3・6H 2O 按一定比例混合,加入沉淀剂(N H 3・H 2O ,搅拌,反应一段时间即得到纳米Fe 3O 4粒子,反应式为:Fe 2++2Fe 3++8N H 3・H 2O =Fe 3O 4↓+8N H +4+4H 2O由反应式可看出,反应的理论摩尔比为Fe 2+∶Fe 3+=1∶2,但由于二价铁离子容易氧化成三价铁离子,所以实际反应中二价铁离子应适当过量.1.3四氧化三铁的制备将一定量的二价铁盐(FeSO 4・7H 2O 和三价铁盐(FeCl 3・6H 2O 混合溶液加入到三口烧瓶中,滴液漏斗中加入一定浓度的沉淀剂N H 3・H 2O ,在氮气氛下将氨水溶液加到反应体系中,使体系的p H ≥10,剧烈搅拌,水浴恒温.搅拌30min 后结束反应,用蒸馏水反复洗涤直至中性,倾去上层清液,在60℃下真空干燥后,研磨即得纳米Fe 3O 4粒子.2纳米Fe 3O 4粒子的表征2.1XR D 分析图1为纳米Fe 3O 4粒子的衍射图,图中的衍射峰出现在2θ=30°,35°,42°,62.5°处,分别对应立方相Fe 3O 4的(220,(311,(400,(440晶面.由Scherrer 公式:D =κλ/βco s θ.式中λ为射线波长,κ为峰形因子,D 为晶体的平均粒径,θ为衍射角,β为校正后的半峰宽.κ值取决于几个因素,其值一般取0.89.取2θ为35°时的半峰宽算出纳米Fe 3O 4粒子的平均粒径为8.8nm.2.2TEM 分析图2为纳米Fe 3O 4粒子的透射电镜图片.图中磁性Fe 3O 4粒子大小较均一,形状为球形,粒子粒径为10~20nm.TEM 得到粒子的平均粒径比XRD 的大,这是由于Scherrer 公式算出的第1期黄菁菁等:化学共沉淀法制备纳米四氧化三铁粒子51粒径为Fe3O4晶体的平均粒径,而TEM看到的粒子可能是多个Fe3O4晶体的团聚体.图1FeO4纳米粒子的XRD的照片图2Fe3O4纳米粒子的TEM谱图3结果与讨论3.1Fe2+、Fe3+溶液浓度对产物粒径的影响在反应体系温度为40℃,二价铁盐和三价铁盐的物质的量比为1∶1,C Fe2+=C Fe3+,N H3・H2O浓度为1mol/L,搅拌速度恒定的条件下,考察了铁盐溶液浓度对Fe3O4粒子粒径的影响,结果如表1所示.表1Fe2+和Fe3+浓度对F e3O4平均粒径的影响试样铁盐浓度/(mol・L-1平均粒径/nm产物颜色a0.2522.1黑b0.1515.5黑c0.1258.8黑褐由表1可知,当铁盐浓度很小时,产物颜色呈现出黑褐色,其原因为Fe2+离子在低浓度时更易被氧化成Fe3+离子,从而使实际参加反应离子的比例发生变化,而生成其他的杂质[8].在铁盐浓度很低时,晶核成长速率较小及成长过程较短,所以产物粒径降低.随着铁盐浓度增加,晶核粒径逐渐增大,生成粒子粒径也逐渐增大.3.2氨水浓度对产物粒径的影响在反应体系温度为40℃,二价铁盐和三价铁盐的物质的量比为1∶1,铁盐溶液浓度为0.25mol/L(C Fe2+=C Fe3+,搅拌速度恒定的条件下,考察了氨水浓度对Fe3O4粒子粒径的影响,结果如表2所示.表2NH3・H2O浓度对Fe3O4平均粒径的影响试样氨水浓度/(mol・L-1平均粒径/nm产物颜色a 1.523.8黑b 1.022.0黑c0.515.5黑由表2可知,当氨水浓度增大时,粒子平均粒径增大.如果氨水浓度增加,就有许多未反应的N H3・H2O附着在粒子表面,从而使产物粒径增大.3.3超声波对产物粒径的影响在反应体系温度为40℃,二价铁盐和三价铁盐的物质的量比为1∶1,C Fe2+=C Fe3+,搅拌速度恒定的条件下,开启超声波发生器,考察超声波对Fe3O4粒子粒径的影响,结果如表3所示.湖北大学学报(自然科学版第28卷52表3超声波对Fe3O4平均粒径的影响试样铁盐浓度/(mol・L-1氨水浓度/(mol・L-1平均粒径/nm产物颜色a0.25 1.523.8黑a30.25 1.517.2黑b0.25 1.022.1黑b30.25 1.09.4黑3为反应时引入超声波由表3可知,当反应物条件相同的情况下,超声波的引入使制得的Fe3O4粒子粒径减小.这可能是(1超声波使体系湍动状态加剧,晶核成长受到一定阻碍,所以产物粒径有所降低;(2超声波的分散作用使成形的Fe3O4粒子难以发生团聚,这样使产物的最终粒径减小.4结论采用化学共沉淀法制备纳米Fe3O4粒子,其粒径大小随铁盐溶液浓度和氨水浓度的增加而增大.在搅拌的同时引入超声波,可使产物粒径减小.改变实验条件,可制得平均粒径在10nm以下的纳米Fe3O4粒子.参考文献:[1]Yamguchi K,Matsumoto K,Fiji T.Magnetic anisotropy by ferromagnetic particles alignment in a magnetic field[J].J Appl Phys,1990,67:44934495.[2]Odenbach S.Magnetic fluids[J].Adv Colloid Interface Sci,1993,46:263282.[3]Atarshi T,Imai T.On the preparation of the colored water2based magnetic fluids cred,yellow blue and black[J],Magn Magn Mater,1990,85:3 6.[4]Caceres P G,Behbehani M H.Microstructural and surface area development during hydrogen reduction of magnetite[J],Appl Catal A,1994,109:211223.[5]Chikov V,Kuznetsov A.Single cell magnetophoresis and its diagnostic value[J],J Magn Magn Mater,1993,122:367370.[6]Fan R,Chen X H,Gui Z,et al.A new simple hydrothermal prepation of nanocrystalline magnetite Fe3O4[J].Materials Research Bulletin,2001,36:497502.[7]丁明,曾桓兴.中和沉淀法Fe3O4的生成研究[J].无机材料学报,1998,13:619624.[8]秦润华,姜炜,刘红缨,等.纳米磁性四氧化三铁的制备和表征[J].材料导报.2003,17:6668.[9]Zhu Y ihua,Wu Qiufang.Synthesis of magnetite nanoparticles by precipitation with forled mixing[J].Journal ofNanoparticle Research,1999,1:393396.[10]Wang Shizhong.Xin Houwen,Qian Y itai.Preparation of nanocry stallineFe3O4byγ2ray radition[J].MaterialsLetters,1997,33:113116.[11]Khollam Y B,Dhage S R,Potdar S B,et al.Microwave hydrothermal preparation of submicron2sized sphericalmagnetite(Fe3O4powders[J].Materials Letters,2002,56:571577.Fe3O4nanoparticles prepared by chemical co2precipitation methodHUAN G Jing2jing,XU Zu2shun,YI Chang2feng(School of Materials Science and Engineering,HubeiUniversity,Wuhan430062,China Abstract:Fe3O4nanoparticles were prepared by chemical co2precipitation met hod.The p roperties of Fe3O4nanoparticles were characterized by X2ray diffraction(XRDand t ransmission elect ronmicroscopy(TEM.The effect s of t he concent ration of Fe2+,Fe3+,N H3・H2O and t he ult rasonic on t he average diameter of t he Fe3O4nanoparticles are st udied.K ey w ords:chemical co2precipitation met hod;Fe3O4;ult rasonic(责任编辑晏建章。

波导型高功率微波输能窗的研究进展

·高功率微波技术•综述·波导型高功率微波输能窗的研究进展*张　雪1，王　滔1，俞倩倩1，王　勇2,3（1. 湘潭大学自动化与电子信息学院，湖南湘潭 411105； 2. 中国科学院空天信息创新研究院，北京 101407； 3. 中国科学院大学，北京 100049）摘要：波导型高功率微波输能窗是高功率速调管和高能粒子加速器的关键部件，输出窗高频击穿是引起高功率速调管失效的一个重要因素。

综述了国内外电真空领域波导型输能窗的研究进展，介绍了传统盒型窗的研究现状、工艺要求和击穿机理；介绍了锥型窗、行波窗、复合模窗以及过模窗等新型输能窗的设计特点，给出了改变窗片材料属性、改变窗片表面形态、窗片边缘倒角、外置直流电场/直流磁场、改变信号波形等击穿抑制技术的研究进展。

关键词：高功率微波；速调管；输能窗；盒型窗；行波窗；击穿抑制技术中图分类号： TM21 文献标志码： A doi : 10.11884/HPLPB202133.200257Research progress of high-power waveguide windowZhang Xue 1， Wang Tao 1， Yu Qianqian 1， Wang Yong 2,3（1. School of Automation and Electronic Information , Xiangtan University , Xiangtan 411105, China ;2. Aerospace Information Research Institute , Chinese Academy of Sciences , Beijing 101407, China ;3. University of Chinese Academy of Sciences , Beijing 100049, China ）Abstract ： High-power waveguide window is a critical component of high-power klystron and accelerator. The RF breakdown of the waveguide window always cause the failure of the high-power klystron. In this paper, the research progress of high-power waveguide window in the international vacuum electronics field is introduced. The research status, manufacturing requirement, and RF breakdown mechanism of the classical pill-box window are presented at first. Then the characters of some new type waveguide windows such as the tapered window, travelling wave in ceramic window, mixed-mode window, and over-mode window are summarized. Some breakdown suppression technologies like changing the material character of the window disk, changing the surface configuration of the window disk, using the positive dielectric angle, applying DC electric field or DC magnetic field, changing the waveform of transverse electric field are emphasized at the end.Key words ： high-power microwave ； klystron ； high-power waveguide window ； pill-box window ；travelling wave in ceramic window ； breakdown suppression technique波导型高功率微波输能窗是保持高功率速调管和高能粒子加速器内部真空环境的关键部件。

ARAMCO阿美认证检验员考试题及答案

1. What is the purpose of a penetrameter or IQI?Indicates radiographic sensitivity and quality of the techniques.2. What is meant by the term sensitivity with regard to radiography?The ability of a radiographic technique to reveal defects of a specific size.3. What are the limitations of magnetic particle inspection and liquid penetrant inspection?M.P. can be used only on ferromagnetic materials to detect surface subsurface discontinuities.L.P. can be used to detect defects open to the surface.Both M.P. and L.P. require surface preparations before testing.4. What information is contained in a Welding Procedure Specification?Process type, groove (joint) design, material type, material thickness, position of groove, filler metal type, pre-heat requirements, interpass temperature, post weld heat treatment requirements, shielding gas or flux type, electrical characteristics, techniques of welding.5. Why is post weld heat treatment required for some type weldments?Relieve stresses, lower hardness6. What is the basic difference between a DIN and an ASME penetrameter?DIN penetrameter is a wire type penetrameter,ASME penetrameter is a hole type penetrameter.7. What type of defects would you expect to find during visual inspection of a completed weld? Undercutting, excessive or insufficient weld reinforcement, excessive irregularities, incomplete penetration on a single butt-weld, weld spatter, etc..8. What precaution must be taken with low hydrogen welding electrodes?Store in oven when not in use, kept in heated container by welder awaiting use.9. What information normally appears on radiography?Penetrameter identification, Location of markers to ensure complete coverage, the name of the inspecting laboratory, the date, the part number, whether original or subsequent exposure.10. What is the rule of thumb used to determine the amperage for the dry, prod method of magnetic particle inspection?100 – 125 amps / inch.11. What materials are the transducer made from?Quartz, Barium Titanate, Lithium Sulphate and Ceramics.12. What is a film defect?A mark on the film usually caused by improper handling or processing.13. If you were inspecting an item using the prod method and located a weak crack pattern, where would you place the prods to obtain a stronger location?Relocate prods 90 degrees to the crack pattern and re-inspect.14. What typical defects would you expect while inspecting a casting?Sand and slag inclusions, gas porosity, shrinkage, hot tears.15. Describe the pulse echo technique.When an electric current is applied to the crystal, the crystal vibrates transforming the electric energy into mechanical vibrations which are transmitted through a coupling medium into the test material. These pulse vibrations propogate through the object and are reflected as echoes from both discontinuities and the back surface of the test piece and will appear as a vertical deflection on the cathode ray tube or oscilloscope. 16. Which method i.e. magnetic particle examination or liquid penetrant examination, locate non-metallic inclusions open to the surface.Both.17. What is a ―Weld Procedure Qual ification Record?A document which contains, essentially the same information as a WPS but includes the results of the tests necessary to qualify the WPS. Also listed are the ―essential variable‖ of the specific process of processes. 18. What is meant by t he term ―Film Density‖?Measurement or film blackening.测量或胶片的发黑度。

HSK甲级词汇

id class_id chin_charactetype phoneticize1p honeticizeenglish etype11啊叹aāeh; oh int.part.21啊助aɑ(used at the e31矮形aiǎi short adj.41爱动aiài love v.51爱人名airenàiren husband or w n.61安静形anjingānj ìng quiet; peacef adj.v.n.71安排动、名anpaiānpái arrange; plan81八数ba bāeight num.91把量ba bǎfor sth.with a m.101把介ba bǎused to ship t prep.111爸爸名baba bàbɑdad; fathern.121吧助ba bɑindication a s part.131白形bai bái white adj.num.141百数bai bǎi hundred; num151摆动bai bǎi put; place; a v.161班名、量ban bān spot; speck; n.v.171搬动ban bān move; take a181半数ban bàn half; semi-num.191半天名bantian bàntiān half of the da n.201办动ban bàn do; handle; v.211办法名banfa bànfǎway; means;n.221办公室名bangongshibànɡōnɡshìoffice n.231帮助动bongzhu bānɡzhùhelp; assist; v.241饱形bao bǎo have eaten o adj.251抱动bao bào hold or carry v.261报名bao bào newspaper n.271杯名、量bei bēi cup n.m.281杯子名beizi bēizǐcup; glass n.291北名bei běi north n.301北边名beibian běibiān north n.311倍量bei bèi times m.321被介bei bèi used in a pas prep.331本名、量ben běn book; forboo n.m.341本子名benzi běnzi book; notebo n.351比介、动bi bǐthan; compa prep.v.361比较副、动bijiao bǐjiào compare; co ad. v.371比赛动、名bisai bǐsǎi match; comp v.n.381笔名、量bi bǐpen; pencil o n.m.391必须助动、副bixu bìxūmust; have t v.aux.v.401边名bian biān side; margin;n.411变动bian biàn become diffe v.421变成biancheng biàn chénɡchange into; turn into; become; tran 431变化动、名bianhua biànhuàchange; vary v.n.441遍量bian biàn(for actions)o m.451表名biao biǎo watch.(a time n.v.n.461表示动、名biaoshi biǎoshìshow; expresv.n.471表现动、名biaoxian biǎoxiàn show; display481表演动、名biaoyan biǎoyǎn perform; act;v.n.491表扬动biaoyang biǎoyánɡpraise; comm v.501别副bie bié(used in givin ad.pro.511别的代biede biéde other; anothepro.521别人代bieren biéren someone else531病名、动bing bìnɡill; sick; disean.v.541不错形bucuo búcuònot bad; prett a.551不但连budan búdàn(used correla而且 ²¢且)not onlyconj.561不要副buyao búyào don't ad.571不用副buyong búyònɡneed not ad.581不副bu bù(used before 有)not; wad.591不久名bujiu bùjiǔsoon; before n.601不如动、连buru bùrúnot equal to; v.conj.611不同butong bùtónɡnot like; different;621布名bu bùcotton cloth; n.631部分名bufen bùfen part; section;n.641擦动ca cārub; wipe;v.651才副cai cái a moment ag ad.661菜名cai cài vegetable; gr n.671参观动canguan cānɡuān visit; have a v.681参加动canjia cānjiājoin(a group; v.691操场名caochang cāochānɡplayground; sn.701草名cao cǎo grass;n.711层量ceng cénɡstorey; floor m.721茶名cha chátea(the plant n.731查动cha chácheck; exami v.741差动cha chàdiffer from; f v.ad.751常副chang chánɡfreuently; com761常常副changchang chánɡchánɡfrequently; of ad.771长形chang chánɡ(for space or a.781场量、名chang chǎnɡspell; period;m.n.791唱动chang chànɡsing v.801朝介、动chao cháo facing; towar prep. v.811车名che chēvehicle n.821车站名chezhan chēzhàn station; depot n.831城名cheng chénɡcity wall; wal n.841城市名chengshi chénɡshìtown or city;n.851成动cheng chén…become ; tur v.861成绩名chengji chénɡjīresult(of work n.871吃动chi chīeat; take;v.v.881迟到动chidao chídào be (or come av.891抽动chou chōu take out; take901出动chu chūgo or come o v.v.911出发动chufa chūfāset out; start o921出来chulai chūlái(used after a verb; indicating motion out towards the 931出去chuqu chūqùgo out; get out;v.941出现动chuxian chūxiàn appear; arise951出租汽车chuzuqichechūzūqìchētaxicab; taxi; cab;961除了…以外chuleyiwai chúle…yǐwài except; not counting; not including;971穿动chuan chuān piercethroughv.981船名chuan chuán boat; ship;n.991窗名chuang chuānɡwindow;n.1001窗户名chuanghu chuānɡhùwindow; casen.1011床名chuang chuánɡbed;n.1021吹动chui chuīblow; puff;v.1031春名chun chūn spring;n.n.1041春天名chuntian chūntiān spring; spring1051磁带名cidai cídài(magnetic) ta n.1061词名ci cíword; term;n.1071词典名cidian cídiǎn dictionary;n.1081次量ci cìoccurrence; t m.1091从介cong cóng from(a time; prep.1101从……到……congdao cóng……dào from…to…1111从……起congqi cóng……qǐsincen.1121从前名congqian cóngqián before; forme1131错形、名cuo cuòintricate; wro a.n.n.1141错误名cuowu cuòwùwrong; mistak1151打动da dǎstrike; hit ; k v.1161打算动、名dasuan dǎsuàn plan; intend;v.n.a.n.1171大形da dàbig ; large; g1181大概形dagai dàɡài general idar; a.n.1191大家代dajia dàjiāall; everybodypro.1201大声名dasheng dàshēnɡloudn.1211大学名daxue dàxuéuniversity; co1221大夫名daifu dàifu doctor; a seni n.1231戴动dai dài put on; wear;v.1241带动dai dài take; bring; v.1251代表名、动daibiao dàibiǎo deputy; deleg n.v.1261但是连danshi dànshìbut; yet; still conj.1271当介dang dānɡin sb.'s prese prep.1281当动dang dānɡmatch equal t v.1291当然形dangran dānɡrán natural a.1301刀名dao dāo knife; sword;n.v.1311倒动dao dǎo move backwa1321到动dao dào arrive; reach v.1331道量dao dào( for long and m.1341道理名daoli dàolǐprinciple; rea n.v.1351得动de déget; obtain; (o1361得到dedao dédào get; gain; receive;v.aux.1371的助de de(used after anv.aux.1381地助de de(used after an1391得助de de(used after a v; aux1401……得很dehen……dehěn quite; very1411得助动dei děi need; must; v.aux.1421灯名deng dēnɡlamp; lantern n.1431等动deng děnɡwait; await;v.1441等助deng děnɡ(used after a v.aux.a.v.1451低形、动di dīlow; let droopn.1461地名di dìthe earth; lan1471地方名difang dìfang place; space;n.1481第(第一)头di dì(dìyī)(used before numerals to form ordinal numbers);n.1491弟弟名didi dìdi younger broth1501点名dian diǎn drop(of liquid n.a.1511点形dian diǎn point; a unit ov.1521点动dian diǎn drip; light; chn.1531点心名dianxin diǎnxin light refreshm1541点钟名dianzhong diǎnzhōnɡo'clock;n.1551电名dian diàn electricty;n.1561电车名dianche diànchētram; tramcar n.1571电灯名diandeng diàndēnɡelectric lamp;n.1581电话名dianhua diànhuàtelephone; ph n.1591电视名dianshi diànshìtelevision; TV n.n.1601电影名dianying diànyǐng film; movie; m1611掉动diao diào fall; drop; she v.1621丢动diu diūlose; mislay;v.1631东名dong dōnɡeast;n.1641东边名dongbian dōnɡbiān east;n.1651东西名dongxi dōnɡxi thing;n.1661冬名dong dōnɡwinter;n.1671冬天名dongtian dōnɡtiān winter;n.1681懂动dong dǒnɡunderstand; k v.1691动动dong dònɡmove; stir;v.1701动物名dongwu dònɡwùanimal;n.1711都副dou dōu all;ad.1721读动du dúread; read al v.1731短形duan duǎn short; brief;a.1741锻炼动duanlian duànliàn take exercise v.m.1751段量duan duàn section; segm1761对介、动dui duìwith regard to prep.v.1771对量dui duìpair; couple;m.1781对不起duibuqi duìbuqǐI'm sorry; sorry; excuse me;1791顿量dun dùn three meals a m.1801多形duo duōmany; much; a.1811多副duo duō(used in ques ad.1821多数duo duōover a specifi num.1831多么副duome duōme(used in ques ad.1841多少代duoshao duōshao how much; h pro.1851饿形、动eèhungry; starv a.v.1861而且连erqieérqiěand also; but conj.1871儿子名erziérzi son;n.1881二数erèr two;num.1891发动fa fāsend out; iss v.1901发烧fashao fāshāo have(or run)a fever; have(or run) a temperature;v.1911发生动fasheng fāshēnɡhappen; occuv.n.1921发现动、名faxian fāxiàn discover; findv.n.1931发展动、名fazhan fāzhǎn develop; expa1941法语(法文)名fayu(fawen)fǎyǔ(fǎwén)French(langu n.v.1951翻动fan fān turn upside dov.n.1961翻译动、名fanyi fānyìtranslate; inte1971反对动fandui fǎnduìoppose; be a v.1981饭名fan fàn meal;n.1991饭店名fandian fàndiàn hotel; restaur n.a.v.2001方便形、动fangbian fānɡbiàn convenient; m2011方法名fangfa fānɡfǎmethod; way;n.n.2021方面名fangmian fānɡmiàn respect; aspen.2031方向名fangxiang fānɡxiànɡdirection; orie2041房间名fangjian fánɡjiān room;n.2051访问动、名fangwen fǎnɡwèn visit; call on;v.n.2061放动fang fànɡlet go; set fre v.2071放假fangjia fànɡjiàhave a holiday or vacation; have a day off; 2081非常副feichang fēichánɡvery; extrem a d.2091飞动fei fēi(of birds of in v.2101飞机名feiji fēijīaircraft; aero n.2111分动fen fēn divide; allot v.n.m.2121分名、量fen fēn minute; (for n(used in spoken forms of fractions; a 2131……分之……fenzhi……fēnzhī……2141分钟名fenzhong fēnzhōnɡminute;n.a.v.2151丰富形、动fengfu fēnɡfùrich; abundan2161封量feng fēnɡ(for sth. enve m.2171风名feng fēnɡwind;n.2181夫人名furen fūren a lady of high n.2191服务动fuwu fúwùgive service t v.2201服务员名fuwuyuan fúwùyuán attendant;n.v.n.2211辅导动、名fudao fǔdǎo give guidancev.2221复习动fuxi fùxíreview; revise2231复杂形fuza fùzácomplicated; a.2241父亲名fuqin fùqīn father;n.2251负责动、形fuze fùzébe responsibl v.a.2261附近名fujin fǔjìn nearby; neighn.2271该助动、动gaiɡāi ought to be; v.aux.v. 2281改动gaiɡǎi change; tran v.2291改变动、名gaibianɡǎibiàn change; alter v.n.a.2301干净形ganjingɡānjìnɡclean; neat an2311感到动gandaoɡǎndào feel; sense;v.2321感冒动、名ganmaoɡǎnmào common cold v.n.2331感谢动ganxieɡǎnxièthank; be gra v.2341敢助动ganɡǎn be brave eno v.aux. 2351干动ganɡàn do; work;v.2361干部名ganbuɡànbùcadre;n.2371刚副gangɡānɡjust; exactly;ad.2381刚才名gangcaiɡānɡcái a moment ag n.n.2391钢笔名gangbiɡānɡbǐpen; fountain2401高形gaoɡāo tall; high; a.2411高兴形、动gaoxingɡāoxìnɡglad; happy; a.2421搞动gaoɡǎo do; carry on;v.2431告诉动gaosuɡàosu tell; let know v.2441哥哥名gegeɡēɡe(elder)brother n.2451歌名geɡēsong;n.m.2461个量geɡè(before nouns2471各代geɡèeach; every; pro.2481各种代gezhongɡèzhǒnɡevery; each; pro.prep.v. 2491给介、动geiɡěi give; grant; (um.n.2501根量、名genɡēn(for long , thinprep.conj.v 2511跟介、连、动genɡēn(used to showad.2521更副gengɡènɡmore; still mo2531工厂名gongchangɡōnɡchǎnɡfactory; mill; n.2541工人名gongrenɡōnɡrén worker; work n.2551工业名gongyeɡōnɡyèindustry;n.2561工作动、名gongzuoɡōnɡzuòwork; operate v.n.bus;2571公共汽车gonggongqichɡōnɡɡònɡqìchē2581公斤量gongjinɡōnɡjīn kilogram(kg.)m.2591公里量gongliɡōnɡlǐkilometre;m.2601公园名gongyuanɡōnɡyuán park;n.2611够形、动gouɡòu enough; suffica.v.2621姑娘名guniangɡūnianɡgirl;n.2631故事名gushiɡùshìstory; tale;n.2641刮动guaɡuāscrape; shav v.2651挂动guaɡuàhang; put up v.2661关动guanɡuān shut; close; v.2671关系名、动guanxiɡuānxìconnections; n.v.2681关心动guanxinɡuānxīn be cnocernde v.2691馆名guanɡuǎn accommodati n.2701广播动、名guangboɡuǎnɡbōbroadcast;n.2711贵形guiɡuìexpensive; c a.2721贵姓guixingɡuìxìnɡhonor your;2731国名guoɡuócountry; nation.n.2741国家名guojiaɡuójiācountry; natio2751过动guoɡuòcross; pass;v.2761过助guoɡuòexceed; go b v.aux.2771过来guolaiɡuòlái come over; come up;n.2781过去名guoquɡuòqùthe past; form2791过去guoquɡuòqùgo over; past by;2801哈哈象声haha hāhāsee;ad.2811还副hai hái still; yet; even2821还是副、连haishi háishìstill; yet; (expad.2831孩子名haizi háizǐchild; son or n.2841海名hai hǎi sea or big lak n.2851寒假名hanjia hánjiàwinter vacation.2861喊动han hǎn shout; cty ou v.2871汉语名hanyu hànyǔChinese(lang n.2881汉字名hanzi hànzìChinese char n.a.2891好形hao hǎo good; fine; n2901好副hao hǎo(used before ad.2911好吃形haochi hǎochīdelicious, gol a.2921好处名haochu hǎochùgood; benefi n.2931好看形haokan hǎokàn good-looking;a.ad.2941好像动haoxiang hǎoxiànɡseem; be liken.m.2951号名、量hao hào name; (for wo2961喝动he hēdrink;v.2971和介、连he hé(indicating rel prep.conj.2981合适形heshi héshìsuitable; appr a.2991河名he hériver;n.3001黑形hei hēi black; dark;a.3011黑板名heiban hēibǎn blackboard;n.3021很副hen hěn very; very m a d.3031红形hong hónɡred; a.n.a.3041后名、形hou hòu after; afterwa3051后边名houbian hòubiān at the back; i n.3061忽然副huran hūrán suddenly; all ad.3071湖名hu húlake;n.ad.3081互相副huxiang hùxiānɡmutually; eac3091花名、形hua huāflower; bloss n.3101花动hua huāspend; expenv.3111画动hua huàdraw; paint;v.n.3121画儿名huaer huàer drawing; pain3131化学名huaxue huàxuéchemistry;n.3141话名hua huàword; talk;n.3151坏形huai huài bad; harmful a.3161欢迎动huanying huānyínɡwelcome; gre v.3171还动huan huán go back; givev.v.3181换动huan huàn exchange; baad.3191黄形huang huánɡyellow; sallow3201回动hui huíreturn; go ba v.3211回量hui huíchapter;m.v.n.3221回答动、名huida huídáanswer; reply3231回来huilai huílái return; come back; be back; 3241回去huiqu huíqùreture; go back; be back; 3251会助动、动hui huìmeet; see; g v.aux.v.3261会名hui huìmeeting; gat n.3271会话动、名huihua huìhuàconversation(v.n.3281活动huo huólive;v.3291活儿名huoer huóer work; produc n.3301活动动、名huodong huódònɡmove about; v.n.3311火车名huoche huǒchētrain;n.3321或者连huozhe huòzhěor; either…o conj.3331基本形jiben jīběn asocally; in ad.3341基础名jichu jīchǔfoundation; bn.3351机场名jichang jīchǎnɡairport; airfie n.n.3361机会名jihui jīhuìchance; oppo3371机器名jiqi jīqìmachine; ma n.3381鸡名ji jīchicken;n.3391鸡蛋名jidan jīdàn(hen's)egg;n.3401……极了jile……jíle extremely; to the greatest extent; 3411集合动jihe jíhégather; assemv.3421急形ji jífast; rapid; v a.3431挤动、形ji jǐsqueeze; pre v.a.3441几代ji jǐhow much;pro.n.3451技术名jishu jìshùtechnology; s3461寄动ji jìsend; postp; v.3471计划名、动jihua jìhuàplan; project;n.v.v.3481记动ji jìremember; w3491继续动jixu jìxùcontinue; go v.3501家(文学家)名、量、尾jia(wenxuejia jiā(wénxuéjiā)family; (for fa n.m.n.3511家庭名jiating jiātínɡfamily; house3521加动jia jiāadd; plus; in v.3531坚持动jianchi jiānchípersist in; pe v.m.3541间量jian jiān(for rooms); (v.n.3551检查动、名jiancha jiǎnchácheck up; ins3561简单形jiandan jiǎndān simple; unco a.3571见动jian jiàn see; catch si v.3581见面jianmian jiànmiàn meet; see;3591件量jian jiàn(for matters inm.3601健康名、形jiankang jiànkānɡhealth; physi n.a.3611建设动、名jianshe jiànshèbuild; establi v.n.3621将来名jianglai jiānɡlái future;n.3631江名jiang jiānɡriver;n.v.3641讲动jiang jiǎnɡspeal; say; te3651交动jiao jiāo hand over; g v.v.3661教动jiao jiào teach; instruc3671脚名jiao jiǎo foot;n.3681角量jiao jiǎo quarter;m.n.3691饺子名jiaozi jiǎozi dumpling(with3701教室名jiaoshi jiàoshìclassroom; s n.v.n.3711教育动、名jiaoyu jiàoyùeducation; tea3721叫动jiao jiào cry; shout;3731叫介jiao jiào(used in a pasprep.v.3741接动jie jiēcome into con3751接着副、连jiezhe jiēzhe after that; an ad. conj.3761街名jie jiēstreet;n.3771节名、量jie jiéjoint; section n.m.3781节目名jiemu jiémùprogramme;n.n.3791节日名jieri jiérìfestival; red-leconj.3801结果连jieguo jiéɡuǒresult; outcomv.3811结束动jieshu jiéshùend; finish; c3821解决动jiejue jiějuésolve; resolv v.n.3831姐姐名jiejie jiějiěelder sister; s3841借动jie jièborrow;v.3851介绍动jieshao jièshào introduce; prev.m.3861斤量jin jīn jin, currently c3871今年名jinnian jīnnián this year;n.3881今天名jintian jīntiān to day; this d n.3891紧形jin jǐn thight; taut;a.3901紧张形jinzhang jǐnzhāng nervous; key a.3911进动jin jìn advance; mo v.3921进来jinlai jìnlái(used after a verb)in (here); 3931进去jinqu jìnqù(used after a verb)in (there); 3941进行动jinxing jìnxínɡbe in progres v.3951近形jin jìn near; close;a.3961精彩形jingcai jīnɡcǎi brilliant; sple v.3971精神名jingshen jīnɡshén spirit; mind; n.3981经常形jingchang jīnɡchánɡday-to-day; ea.3991经过动、介jingguo jīnɡɡuòpass; go thro v.prep.4001经济名jingji jīnɡjìeconomy;n.4011经验名jingyan jīnɡyàn experience;n.4021久形jiu jiǔfor a long tim a.4031九数jiu jiǔnine;num.4041酒名jiu jiǔalcoholic drin n.4051旧形jiu jiùpast; bygone a.4061就副、连jiu jiùat once; righ ad. conj.4071橘子(桔子)名juzi júzi tangerine;n.4081举动ju jǔlift; raise; ho v.4091句量ju jùsentence;m.4101句子名juzi jùzi sentence;n.4111觉得动juede juéde feel;v.4121决定动、名jueding juédìnɡdecode; reso v.n.4131咖啡名kafei kāfēi coffee;n.4141卡车名kache kǎchēlorry; truck;n.4151开动kai kāi open;v.4161开始动、名kaishi kāishǐbegin; start;v.n.4171开玩笑kaiwanxiaokāiwánxiàocrack a joke; joke; make fun of; 4181开学kaixue kāixuéschool opens; term begins; 4191看动kan kàn see; look at; v.4201看病kanbing kànbìnɡ(of a doctor) see a patient;4211看见kanjian kànjiàn catch sight of; see;4221考试动、名kaoshi kǎoshìtake an exam v.n.4231棵量ke kē(usu, for plan m.4241科学名、形kexue kēxuéscience; scie n.a.4251咳嗽动kesou késou cough;v.4261可能助动、名keneng kěnénɡpossible; pro v.aux.n.conj.4271可是连keshi kěshìbut; yet; how4281可以助动keyi kěyǐcan; may;v.aux.4291渴形ke kěthirsty; a.4301克量ke kègram;m.4311刻量ke kèquarter(of an m.4321客气形、动keqi kèqìpolite; courte a.v.4331课名ke kèclass;n.4341课本名keben kèběn textbook;n.4351课文名kewen kèwén text(of a lesson.4361空气名kongqi kōnɡqìair;n.n.m.4371口名、量kou kǒu mouth(of a hu4381口语名kouyu kǒuyǔspoken langu n.4391哭动ku kūcry; weep;v.4401苦形ku kǔbitter; a.4411块名、量kuai kuài piece; lump; n.m.4421快形kuai kuài fast; quick; r a.4431困难名、形kunnan kùnnan difficulty;n.a.4441拉动la lāpull; drqw; tuv.4451啦助la la see;v.aux.4461来动lai lái come(to);v.4471蓝形lan lán blue; a.4481篮球名lanqiu lánqiúbasketball;n.4491劳动动laodong láodònɡwork; labour;v.4501劳驾laojia láojiàexcuse me; may I trouble you..?a.4511老(老二)(形、头)lao(laoer)lǎo(lǎo'èr)old( not young4521老师名laoshi lǎoshīteacher(somen.4531了助le le(used after a v.aux.4541累形lei lèi tited; weary; a.4551冷形leng lěnɡcold; a.4561离动、介li líleave; part fr v.prep.4571离开likai líkāi leave; depart from; deviate form; 4581里名li lǐlining; inside n.4591里量li lǐcurrently callem.4601里边名libian lǐbiān inside; in; w n.4611礼物名liwu lǐwùgift; present;n.4621历史名lishi lìshǐhistory;n.4631利用动liyong lìyònɡuse; utilize; mv.4641例如动liru lìrúfor instance; v.4651立刻副like lìkèimmediately; ad.4661俩数lia liǎ(a fusion of Ánum.v.4671联系动、名lianxi liánxìcontact; toucheven;v.n.4681连……都(也)liandou(ye)lián……dōu(yě)4691脸名lian liǎn face(of peopl n.4701练习动、名lian liàn practise;v.n.4711凉快形liang liánɡnice and cool a.4721两数liang liǎnɡtwo;num.4731辆量liang liànɡ(for vehicles)m.4741亮形、动liang liànɡbright; light; a.v.v.4751了动liao liǎo finish; conclu4761了解动liaojie liǎojiěunderstand; v.4771零(0)数ling línɡzero; nil;num.4781领导动、名lingdao lǐnɡdǎo lead; exercis v.n.4791留动liu liúremain; stay;v.4801留念liunian liúniàn accept or keep as a souvenir; 4811留学生名liuxuesheng liúxuéshēnɡstudent abroa n.v.n.4821流动、名liu liú(of liquid) flow4831六数liu liùsix;num.4841楼名lou lóu a storied buildn.n.4851路名lu lùroad; path; w4861录音luyin lùyīn tape-record(sound); record; tape; 4871旅行动lüxing lǚxíng travel; journev.4881绿形lülǜgreen; a.a.4891乱形luan luàn in disorder; in4901妈妈名mama māma ma; mum; mn.4911麻烦动、形mafan máfan troublesome; v.a.4921马名ma mǎhorse;n.4931马上副mashang mǎshànɡat once; imm ad.v.aux.4941嘛助ma ma(indicating thav.aux.4951吗助ma ma(used at the e4961买动mai mǎi buy; purchas v.4971卖动mai mài sell;v.a.4981满形man mǎn full; filled; pa4991满意形manyi mǎnyìsatisfied; ple a.5001慢形man màn slow; a.a.5011忙形mang mánɡbusy; fully ocm.5021毛量mao máo a fractional unn.5031帽子名maozi màozi headgear; haad. v.5041没副、动mei méi not have; the5051没关系meiguanxi méiɡuānxi it doesn't matter; it's nothing;5061没意思meiyisi méiyìsi bored;5071没有副meiyou méiyǒu have not or d ad.5081每代mei měi every; each; pro.5091妹妹名meimei mèimei younger siste n.5101门名、量men mén door; gate; (n.m.5111门口名menkou ménkǒu entrance; do n.used after a personal pronoun or a n 5121们（朋友们）尾men(pengyoumen(péngyou5131米（公尺）量mi(gongchi)mǐ(ɡōnɡchǐ)metre;m.5141米饭名mifan mǐfàn(husked)rice;n.5151面包名mianbao miànbāo bread;n.5161面条儿名miantiaoer miàntiáoer noodles;n.n.5171民族名minzu mínzúnation; nation5181明年名mingnian mínɡnián next year;n.5191明天名mingtian mínɡtiān tomorrow; th n.5201名字名mingzi mínɡzi name n.5211母亲名muqin mǔqīn mother n.5221目前名muqian mùqián at present; a n.5231拿动na náhold; take;v.5241哪代na nǎ(used in ques pro.pro.5251哪里（哪儿）代nali(naer)nǎlǐ(nǎe r)where; where5261那代na nàthat pro.5271那连na nàthen; in that conj.5281那个代nage nàɡe that one pro.5291那里（那儿）代nali(naner)nàli(nàner)that place; th pro.5301那么代name nàme so; like that ad.conj.5311那么连name nàme used to conne5321那些代naxie nàxiēthose pro.5331那样代nayang nàyànɡof that kind; pro.part.5341哪助na na used in the sapart.5351呐助na na used in the sa5361南名nan nán south n.5371南边名nanbian nánbiān the southern n.5381男形nan nán man; maleadj.5391难形nan nán difficult; hard adj.5401呢助ne ne(used at the epart.5411内名nei nèi(used as a no n.n.5421内容名neirong nèirónɡcontent; subs5431能助动neng nénɡcan(expressinv.aux.5441能够助动nenggou nénɡɡòu can; be able v.aux.5451嗯叹ng nɡ(used to expr int.5461你代ni nǐyou(secound pro.5471你们代nimen nǐmen you(secound pro.5481年名nian nián year n.5491年级名nianji niánjígrade; year n.5501年纪名nianji niánjìage n.5511年轻形nianqing niánqīnɡyoung adj.v.5521念动nian niàn read aloud; a5531您代nin nín honor you pro.5541牛名niu niúox; cattle n.5551牛奶名niunai niúnǎi milk n.5561农村名nongcun nónɡcūn rural area; con.5571农民名nongmin nónɡmín peasant n.5581农业名nongye nónɡyèagriculture; f n.5591努力形nuli nǔlìmake great e a.a.5601女形 nünǚwoman; fema5611女儿名 nüer nǚ'ér daughter n.5621暖和形、动nuanhuo nuǎnhuo warm; warm a.; n.5631爬动pa pácrawl; creep v.5641怕动pa pàfear; dread v.5651拍动pai pāi clap; pat v.5661排球名paiqiu páiqiúvolleyball n.v.; n.5671派动、名pai pài send; dispatc5681旁边名pangbian pánɡbiān side n.5691跑动pao pǎo run v.5701跑步paobu pǎobùrun; march a n.5711朋友名pengyou pénɡyou friend n.5721碰动peng pènɡtouch; bump v.5731批评动、名piping pīpínɡcriticize; crit v.; n.5741啤酒名pijiu píjiǔbeer n.5751篇量pian piān a piece of wri m.5761便宜形、名pianyi piányi cheap a.; n.5771片量、名pian piàn m.a(for slices m.; n.a.5781漂亮形piaoliang piàoliang beautiful; pre5791票名piao piào ticket n.5801苹果名pingguo pínɡɡuǒapple n.5811瓶名、量ping pínɡ bottle; vase. n.; m.5821破动、形po pòbreak; split. b v.; a.5831七数qi qīseven num.5841骑动qi qíride v.5851起动qi qǐrise v.5861起床qi chuang qǐchuánɡget up; get out of bed5871起来qi lai qǐlái stand up; sit up; rise to one's feet 5881汽车名qi che qìchēcar; automob n.5891汽水名qishui qìshuǐsoda water n.5901铅笔名qianbi qiānbǐpencil n.5911千数qian qiān thousand num5921钱名qian qián money n.5931前名qian qián front n.5941前边名qianbian qiánbiān ahead n.5951浅形qian qiǎn shallow a.5961墙名qiang qiánɡwall n.5971桥名qiao qiáo bridge n.5981青年名qingnian qīnɡnián youth n.5991轻形qing qīnɡlight a.6001清楚形qingchu qīnɡchu clear a.6011晴形qing qínɡfine; clear a.n.6021情况名qingkuang qínɡkuànɡcondition; situ6031请动qing qǐnɡask; request v.6041请假qingjia qǐnɡjiàask for leave6051请问qingwen qǐnɡwèn excuse me6061秋名qiu qiūautumn n.6071秋天名qiutian qiūtiān autumn n.6081球名qiu qiúball n.6091取得动qude qǔdégain; obtain n.6101去动qu qùgo v.6111去年名qunian qùnián last year n.6121全形quan quán complete a.6131全部名quanbu quánbùwhole; total n.6141全体名quanti quántǐall; entire n.6151确实形queshi quèshítrue; reliable a.6161然后副ranhou ránhòu then ad.6171让动rang rànɡlet; allow v.6181热形、动re rèhot; heat up a.; v.6191热情形reqing rèqínɡenthusiasm; a.6201人名ren rén human; peop n.6211人们名renmen rénmen people; men n.6221人民名renmin rénmín the people n.6231任何代renhe rènhéany; witchev pro.6241认识动、名renshi rènshi know; unders v.; n.6251认为动renwei rènwéi think; consid v.6261认真形renzhen rènzhēn conscientious a.6271日名ri rìsun; day n.6281日语（日文）名Riyu Rìyǔ(Rìwén)Japanese n.6291日子名rizi rìzi day n.6301容易形rongyi rónɡyìeasy; simple a.6311肉名rou ròu meat n.6321三数san sān three num.6331散步sanbu sànbùtake a walk; go for a walkn.6341山名shan shān hill; mountain6351商店名shangdian shānɡdiàn store; shopn.6361上名shang shànɡabove6371上动shang shànɡascend v.6381上边名shangbian shànɡbiān upper6391上课shangke shànɡkèattend class; go to class6401上来shanglai shànɡlái come up6411上去shangqu shànɡqù(used as a complement to a verb)up(there); (indicatn.6421上午名shangwu shànɡwǔmorning; fore6431上学shangxue shànɡxuégo to school6441少形、动shao shào few; little; le a.; v.6451社会名shehui shèhuìsociety; com n.6461身体名shenti shēntǐbody n.6471深形shen shēn deep a.6481什么代shenme shénme(used before pro.6491声名、量sheng shēnɡsound; voise.n.; m.6501声调名shengdiao shēnɡdiào tone; note n.6511声音名shengyin shēnɡyīn sound; voise.n.6521生产动、名shengchan shēnɡchǎn produse; pro v.; n.6531生词名shengci shēnɡcíwords(and ph n.6541生活动、名shenghuo shēnɡhuólife. Live n.; v.6551生日名shengri shēnɡri birthday n.6561省名sheng shěnɡprovince n.6571剩动sheng shènɡsurplus; remn v.6581胜利动、名shengli shènɡlìwin.victory v.; n.6591师傅名shifu shīfu master worke n.6601十数shi shíten num. 6611十分副shifen shífēn very ad.n. 6621时候名shihou shíhou(a piont in) tim 6631时间名shijian shíjiān time n. 6641食堂名shitang shítánɡcanteen n. 6651实践动、名shijian shíjiàn practice. Put n.; a. 6661实现动shixian shíxiàn realize; fulfil v. 6671使用动shiyong shǐyònɡuse v. 6681世界名shijie shìjièworld n. 6691事名shi shìmatter; thing n. 6701事情名shiqing shìqinɡaffair n.v. 6711是动shi shì(used like"be" 6721市名shi shìcity; municip n. 6731试动shi shìtry v. 6741收动shou shōu receive v. 6751收拾动shoushi shōushi tidy or pack o v. 6761手名shou shǒu hand n. 6771手表名shoubiao shǒubiǎo watch n. 6781首都名shoudu shǒudūcapital n. 6791输动shu shūlose v. 6801舒服形shufu shūfu comfortable a. 6811书名shu shūbook a. 6821熟形shu shúripe v. 6831数动shu shǔcount v. 6841树名shu shùtree n.m. 6851数学名shuxue shùxuétwo; twin; bo 6861双量shuang shuānɡmathematics n. 6871谁代shui shuíwho pro. 6881水名shui shuǐwater n. 6891水果名shuiguo shuǐguǒfruit n. 6901水平名shuiping shuǐpínɡhorizontal; le n. 6911睡动shui shuìsleep v. 6921睡觉shuijiao shuìjiào go to bed6931说动shuo shuōspeak; say; v. 6941说明动、名shuoming shuōmīnɡexplain; expl v.; n. 6951思想名si xiang sīxiǎnɡthought; thin n. 6961死动si sǐdie v. 6971四数si sìfour num. 6981送动song sònɡ1:deliver; car v. 6991宿舍名sushe sùshèhostel n. 7001酸形suan suān sour; tart a. 7011算动suan suàn1: calculate; v.conj. 7021虽然连suiran suīrán(often used co 7031岁量sui suìm.year(age)m. 7041所以连suoyi suǒyǐconj. A(used conj. 7051所有形suoyou suǒyǒu all a. 7061他代ta tāhe or him pro. 7071他们代tamen tāmen they or them pro. 7081它代ta tāit pro. 7091它们代tamen tāmen they or them pro. 7101她代ta tāshe or her pro. 7111她们代tamen tāmen they or them pro. 7121抬动tai tái lift; raise v. 7131太副tai tài ad.excessive ad. 7141太阳名taiyang tàiyánɡsun n.。

PacBio SEQUELII 准备 HiFi SMRTbell 库说明书

Procedure & Checklist – Preparing HiFi SMRTbell®Libraries using the SMRTbell Express Template Prep Kit 2.0This procedure describes the construction of HiFi SMRTbell libraries for de novo assembly and variant detection applications using the SMRTbell Express Template Prep Kit 2.0 and recommended HiFi sequencing conditions using PacBio’s new Sequel® II Binding Kit 2.2. A minimum input amount of 5 µg of high-molecular weight genomic DNA is recommended for generating HiFi library yields sufficient for running multiple SMRT®Cells on the Sequel II or Sequel IIe System (Sequel II Systems). Note that final HiFi library construction yields will be dependent on the specific size-selection method employed.We recommend fragmenting the gDNA so that the target size distribution mode is between 15 kb - 18 kb. To reduce the presence of fragments >30 kb, PacBio recommends a 2-cycle shearing method on the Megaruptor 3 system. Generally, a narrower fragment size distribution results in more uniform and higher-quality HiFi data. Details regarding DNA shearing conditions (e.g., buffers and DNA sample concentration) are described in the “DNA Requirements for Shearing” section.RequiredEquipment Vendor Throughput Run TimeFemto Pulse AgilentTechnologies Process up to 11 samples per runBatch process up to 88 samples 85 minsMegaruptor 3 Diagenode Shear up to 8 samples at a time40 mins(for 1 cycle of shearing)PippinHT Sage Science Maximum of 20 samples per instrument run 2 hrsBluePippin Sage Science Maximum of 4 samples per instrument run 4.5 hrsSageELF Sage Science Maximum of 2 samples per instrument run 4.5 hrs Table 1: Recommended equipment for HiFi SMRTbell library construction for de novo assembly and variant detection applications.Required MaterialsDNA SizingFemto Pulse Agilent Technologies, Inc. P-0003-0817DNA QuantitationQubit™ Fluorometer ThermoFisher Scientific Q33238Qubit 1X dsDNA HS Assay Kit ThermoFisher Scientific Q33230DNA ShearingMegaruptor 3 System Diagenode B06010003Megaruptor 3 Shearing Kit Diagenode E07010003SMRTbell Library PreparationSMRTbell® Express Template Prep Kit 2.0 PacBio 100-938-900AMPure® PB Beads PacBio 100-265-900SMRTbell® Enzyme Clean Up Kit 2.0 (New*) PacBio 101-932-600Sequencing Primer v5 (New*) PacBio 102-067-400100% Ethanol, Molecular Biology Grade Any MLSWide Orifice Tips (Tips LTS W-O 200UL Fltr RT-L200WFLR) Rainin 30389241Lo-Bind 0.2 mL tube strips USA Scientific, TempAssure1402-4708Multi-channel Pipette Rainin, 17013810Magnetic separation rack V&P Scientific, Inc, VP 772F4-1Thermal Cycler that is 100 µL and 8-tube strip compatible Any MLSSize-selection (One of the following systems)PippinHT System Sage Science HTP00010.75% Agarose Gel Cassettes, Marker 75E Sage Science HPE7510BluePippin System Sage Science BLU00010.75% Agarose Cassettes, Marker S1 Sage Sciences BLF7510SageELF System Sage Science ELF00010.75% Agarose Cassettes Sage Science ELD7510SequencingSequel® II Binding Kit 2.2 (New*)PacBio 101-894-200Sequel® II Sequencing Kit 2.0 PacBio 101-820-200SMRT® Cell 8M Tray PacBio 101-389-001* To obtain a copy of the previous version of this Procedure & Checklist that specifies use of SMRTbell Enzyme Clean Up Kit (PN 101-746-400) and Sequencing Primer v2 (PN 101-847-900), contact ****************.HiFi Library Construction WorkflowPacBio recommends that gDNA samples be resuspended in an appropriate buffer (e.g., Qiagen Elution Buffer) before proceeding with DNA shearing.Figure 1: Workflow for preparing HiFi libraries using the SMRTbell Express Template Prep Kit 2.0.Reagent HandlingSeveral reagents in the SMRTbell Express Template Prep Kit 2.0 (shown in Table 2 below) are sensitive to temperature and vortexing. We recommend to:•Never leave reagents at room temperature.•Always work on ice when preparing master mixes.•Finger-tap followed by a quick spin prior to use.Reagent Where UsedDNA Prep Additive Remove single-strand overhangsDNA Prep Enzyme Remove single-strand overhangs DNA Damage Repair Mix v2 DNA Damage RepairEnd Prep Mix End-Repair/A-tailingOverhang Adapter v3 LigationLigation Mix LigationLigation Additive LigationLigation Enhancer LigationSMRTbell Enzyme Clean Up Mix Nuclease TreatmentSMRTbell Enzyme Cleanup Buffer 2.0 Nuclease TreatmentTable 2: Temperature sensitive reagentsGenomic DNA (gDNA) Quality EvaluationThis procedure requires high-quality, high-molecular weight input gDNA with a majority of the DNA fragments >50 kb as determined by pulsed-field gel or capillary electrophoresis. Any of the three commercially available systems listed in Table 4 below may be used to evaluate gDNA quality, but the Femto Pulse system is highly recommended for high-throughput library construction due to its ability to rapidly process multiple samples in a single run using very low amounts (<1 ng) of DNA per sample. Links to recommended procedures for each system are also provided in the table. Examples of gDNA quality assessment using Bio-Rad’s CHEF Mapper (2A) and Agilent Technologies’ Femto Pulse (2B) are shown in Figure 2. Lanes A3 and B1 correspond to high-quality gDNA samples that are suitable for HiFi library construction using this procedure. Lanes A4 and B2 show degraded gDNA samples that not suitable for use in this procedure.Method ProcedureFemto Pulse Agilent Technologies, Inc.Bio-Rad CHEF Mapper XA Pulsed Field Electrophoresis System Procedure & Checklist - Using the BIO-RAD® CHEF Mapper® XA Pulsed Field Electrophoresis SystemSage Science Pippin Pulse Procedure & Checklist - Using the Sage Science PippinPulse Electrophoresis Power Supply SystemTable 3. gDNA Quality Evaluation Methods and Procedures.Figure 2: Evaluation of high-molecular weight gDNA quality using two DNA sizing analysis systems. A) Bio-Rad CHEF Mapper and B) Agilent Technologies’ Femto Pulse.165.510 kb 50 kb 42 kb33 kb 21 kb 17.7 kb 1.3 kb1 bpLane 1: 8 kb - 48 kb Ladder (Bio-Rad) Lane 2: 5 kb ladder (Bio-Rad) Lane 3: HMW gDNA Lane 4: Degraded gDNALane 1: HMW gDNALane 2: Degraded gDNA Lane 3: 165 kb ladder48 kb-20 kb-80 kb----------10 kb-14322 1 3ABDNA Requirements for ShearingBefore shearing, ensure that the genomic DNA is in an appropriate buffer (e.g.,Qiagen Elution Buffer, 10 mM Tris-Cl, pH 8.5 or PacBio EB buffer). If you are unsure of the buffer composition or if the gDNA is not in Elution Buffer, perform a 1X AMPure PB bead purification followed by elution with Elution Buffer or an equivalent low salt buffer (i.e., 10 mM Tris-Cl, pH 8.5- 9.0).PacBio highly recommends Diagenode’s Megaruptor 3 system for shearing gDNA. The Megaruptor 3 system allows up to 8 gDNA samples to be processed simultaneously with a consistent fragment size distribution across multiple hydropore-syringes. Furthermore, the Megaruptor 3 system generates a narrower size distribution than the g-TUBE device (Covaris).Shearing Using Diagenode’s Megaruptor 3 SystemTo maximize HiFi yield per SMRT Cell, PacBio recommends fragmenting the gDNA to a size distribution mode between 15 kb – 18 kb for human whole genome sequencing. Libraries with a size distribution mode larger than 20 kb are not recommended for HiFi sequencing. Recommended library insert size distributions to use for different WGS applications are summarized in Table 4 below.Application Recommended Library Insert SizeHuman Variant Detection 15 – 18 kbHuman de Novo15 – 18 kbPlant/Animal de Novo15 – 20 kbTable 4: Library size recommendations for Human variant detection and de novo assembly.To shear gDNA on the Megaruptor 3 system, use a two-cycle shear method, which requires running a second round of shearing immediately following the first fragmentation step in the same hydropore-syringe. The recommended concentration is 83.3 ng/µL (5 µg of input DNA in 60 µL Elution Buffer).The DNA shearing guidelines below have been tested by PacBio on the Megaruptor 3 system only. The response of individual gDNA samples to the shearing recommendations described below may differ; therefore, performing a small-scale test shear is highly recommended, including the Megaruptor 3 system.For the Megaruptor and Megaruptor 2 systems, shearing optimization is necessary before proceeding with this Procedure & Checklist. The shearing procedure described in the “Shearing Using Diagenode’s Megaruptor 3 system” section below is not compatible with the Megaruptor or Megaruptor 2 systems. For Megaruptor and Megaruptor 2 systems, follow Diagenode’s DNA shearing recommendations described in their manual. For additional guidance, contact Technical Support or your local FAS.The g-TUBE device generates a broader DNA fragment size-distribution compared to the Megaruptor 3 system. Note that HiFi read quality and overall HiFi data yield may be reduced due to the residual presence of large DNA fragments generated by g-TUBEs. For additional guidance, contact Technical Support or your local FAS.Figure 3: Examples of human genomic DNA samples sheared to a target 15 kb - 18 kb size distribution mode using a 2-cycle shear method on the Megaruptor 3 system.Prepare SMRTbell LibrariesAlways work on ice throughout the library construction process. To process multiple samples at a time, the following equipment are required:• Lo-Bind tube strips• Multi-channel pipette• Wide-bore tips• Magnetic rack compatible with tube strips• Thermocycler compatible with tube stripsRemove Single-Strand OverhangsThe sample volume recovered from the Megaruptor 3 system after shearing is used directly in the single-strand overhang digestion step. Before proceeding, ensure that the sheared DNA is in Elution Buffer or an equivalent low salt buffer (i.e., 10 mM Tris-Cl, pH 8.5- 9.0). In this step, DNA Prep Additive is diluted first followed by digestion. Scale up the reaction volumes for digestion if working with multiple samples.1. Prepare the DNA Prep Additive. The DNA Prep Additive is diluted with Enzyme Dilution Buffer toa total volume of 5 µL. This amount is sufficient for processing 1 to 4 samples. The volume maynot be sufficient for 5 samples due to pipetting errors. We recommend scaling up the dilutionvolume based on the number of samples to be processed (example: prepare 2X volume for 8samples and 4X volume for 16 samples).Note: The diluted DNA Prep Additive should be used immediately and should not be stored.2. Prepare the digestion by following the reaction table below. For multiple samples, prepare amaster mix, followed by addition of 10.0μL master mix to each sheared DNA sample.3. Add 10.0 µL of the above master mix to the tube-strips containing 45.0 µL - 53.0 µL of shearedDNA. The total volume in this step is 55.0 µL - 63.0 µL.4. Using a multi-channel pipette, mix the reaction wells by pipetting up and down 10 times with wide-orifice pipette tips.5. Spin down the contents of the tube strips with a quick spin in a microfuge.6. Incubate at 37°C for 15 minutes, then return the reaction to 4°C.7. Proceed to the next step.Repair DNA DamageTo each Reaction Mix 1, add 2.0 µL of DNA Damage Repair Mix v2.1. Mix the reaction well by pipetting up and down 10 times with wide-orifice pipette tips.2. Spin down the contents of the tube strips with a quick spin in a microfuge.3. Incubate at 37°C for 30 minutes, then return the reaction to 4°C.4. Proceed to the next step.End-Repair/A-tailingTo each Reaction Mix 2, add 3.0 µL of End Prep Mix.1. Mix the reaction well by pipetting up and down 10 times with wide-orifice pipette tips.2. Spin down the contents of the tube strips with a quick spin in a microfuge.3. Incubate at 20°C for 10 minutes.4. Incubate at 65°C for 30 minutes, then return the reaction to 4°C.5. Proceed to the next step.Adapter LigationIn this step, 5.0 µL of Overhang Adapter is added to each Reaction Mix 3 (from the previous step). Then, 32.0 µL of the ligase master mix is added to each Reaction Mix 3/Adapter Mix for incubation. Always work on ice. 1. To each Reaction Mix 3, add 5.0 µL of Overhang Adapter.2. Mix the reaction well by pipetting up and down 10 times with wide-orifice pipette tips. Leave the tube strips on ice.3. Prepare a Master Mix containing Ligation Enhancer, Ligation Additive and Ligation Mix using the table4. Mix the reaction well by pipetting up and down 10 times with wide-orifice pipette tips. It is important to mixwell.5. To the Reaction Mix 3/Adapter Mix, add 32.0 µL of the Ligase Master Mix. The total volume in this step is97.0 µL- 105.0 µL.6. Mix the reaction well by pipetting up and down 10 times with wide-orifice pipette tips. It is important to mixwell.7. Incubate at 20°C for 1 hour. Optional: The Ligation reaction may also be left at 20°C overnight.8. Proceed to the next step.Purify SMRTbell Library Using 1.0X AMPure® PB BeadsPage 11 PN 101-853-100 Version 05(August 2021)Nuclease Treatment of SMRTbell LibraryTo each library sample, add the nuclease mix to remove damaged SMRTbell templates.1. Prepare a Master Mix of the Enzyme Cleanup Mix and Buffer.2. Mix the reaction well by pipetting up and down 10 times with wide-orifice pipette tips. It is important to mixwell.3. Spin down the contents of the tube strips with a quick spin in a microfuge.4. To each 15.0μL of sample, add 55.0 μL of Nuclease Master Mix. The total reaction volume at this step is70.0 µL.5. Mix the reaction well by pipetting up and down 10 times with wide-orifice pipette tips. It is important to mixwell.6. Incubate at 37°C for 30 mins and store on ice immediately.7. Spin down the contents of tube strips with a quick spin in a microfuge.8. Proceed directly to the AMPure PB bead purification step below immediately. Do not store samples at thisstage. Do not let samples sit for long periods of time. Always work on ice.Page 12 PN 101-853-100 Version 05(August 2021)Purify SMRTbell Library Using 1.0X AMPure® PB BeadsSize Selection of SMRTbell LibrariesFor high-throughput whole genome sequencing applications, PacBio highly recommends the PippinHT system (Sage Science) for size-selection of SMRTbell libraries for HiFi sequencing. Typical recovery yields are 35% - 50% and are highly dependent on the size distribution of the starting SMRTbell library.Size Selection Using the PippinHT SystemVerify that your PippinHT system software is up to date and follow the procedure below to remove SMRTbellSize Selection Using the BluePippin SystemSage Science’s BluePippin system may also be used for size-selection of HiFi SMRTbell libraries. Verify that your BluePippin system software is up to date and follow the procedure below to remove SMRTbell templates <10 kb using the BluePippin system. Typical recovery yields are highly dependent on the size distribution of the starting SMRTbell library. For the latest BluePippin system User Manual and guidance on size-selection protocols, contact Sage Science ().Size Selection Using the SageELF SystemSage Science’s SageELF system may also be used to fractionate SMRTbell libraries for HiFi whole genome sequencing applications. Verify that your SageELF system software is up to date and follow the size selection procedure below. For the latest SageELF User Manual and guidance on size-selection protocols, contact Sage Science ().6Set up the run Protocol:– In the “Protocol Editor” tab, click on the “New Protocol” button.– Select the “0.75% 1-18kb v2” in the cassette definition menu.– Select “size-based” for separation mode.– Enter 3450 in the “Target Value” field and move the bar slider to selectwell #12.– Save as new protocol.– On the Main screen, clear previous run data, select cassette description,cassette definition and protocol, enter sample ID(s).– Select in the Nest Selector the cartridge that will be run.7Start the run.8 Once the run is complete, (approximately 4.5 hours), collect 30 μL of the respectivefractions from the elution wells. Fractions of interest are typically ~11 kb, ~13 kb,~15 kb, ~17 kb.9 Check the sizes of all 12 fractions by loading on a Femto Pulse. To determine theaverage library size, perform a smear analysis by selecting the region of interestby defining the start and end points of the fractions.10 Pool together fractions that have an average library size 10 – 20 kb.11 Proceed to the AMPure PB Bead purification step.Purify Size-Selected HiFi Library Fractions with 1.0X AMPure ® PB BeadsSequencing PreparationSee Quick Reference Card - Loading and Pre-Extension Recommendations for Sequel II/IIe Systems .For Research Use Only. Not for use in diagnostic procedures. © Copyright 2020 - 2021, Pacific Biosciences of California, Inc. All rights reserved. Information in thisdocument is subject to change without notice. Pacific Biosciences assumes no responsibility for any errors or omissions in this document. Certain notices, terms, conditions and/o r use restrictions may pertain to your use of Pacific Biosciences products and/or third p arty products. Please refer to the applicable PacificBiosciences Terms and Conditions of S a le and to the applicable license terms at /lice nses.html. Pacific Biosciences, the Pacific Biosciences logo, PacBio, S M RT, SMRTbell, Iso-Seq and Sequel are trademarks of Pacific Biosciences. Femto Pulse and Fragment Analyzer are trademarks of Agilent Technologies. All other trademarks are the sole property of their respective owners.Revision History (Description)Version Date Initial release.01 September 2019 Internal revision with no content change (not uploaded to website).02 December 2019 On page 1, changed “HiFi reads” to just “Reads”. On page 12, under Repair DNA Damage,corrected “remove single strand overhangs” to “repair DNA damage”. On page 13, corrected “remove single strand overhangs” to “adapter ligation”.03 January 2020 Updated for SMRTbell Enzyme Clean Up Kit 2.0 and Sequencing Primer v5.04 April 2021 Removed SMRT Link Sample Setup and Run Design tables. Added reference to QRC.05August 2021。

英语三级笔译综合能力2004年试卷、答案及解析

英语三级笔译综合能力2004年试卷Section 1 Vocabulary and Grammar (25 points)This section consists of three parts. Bead the directions for each part before answering the questions. The time for this section is 25 minutes.Part 1 Vocabulary SelectionIn this party there are 20 incomplete sentences. Below each sentence, there are four choices respectively marked by letters A, B, C and D. Choose the word or phrase which best completes each sentence. There is only ONE right answer. Then blacken the corresponding letter with a single bar across the square brackets on your Machine-scoring ANSWER SHEET.1. Grover Cleveland was the first president ______ in the White House.A. got marriedB. to get marriedC. has got marriedD. was married2. If cauliflowers are not _____ from extreme temperatures, the heads get discolored.A. protectedB. shelterC. shadeD. saved3. The gas ______ from the tank is dangerous.A. given offB. giving outC. giving awayD. given up4. When it started to snow, we turned round and _____ the hotel.A. got byB. searched forC. made forD. cleared up5. Since writing home to their parents for money, they had lived _____ hope.A. inB. forC. onD. through6. Rice is the ______ food of most Southeast Asians.A. commonB. generalC. stapleD. popular7. William Byrd was the owner of the largest library in colonial ______.A. periodB. timeC. timesD. periods8. Exobiology is the study of life ______ other planets.A. inB. atC. onD. to9. The Declaration of Independence, _______ the Constitution of the United States,was drawn up with the help of Benjamin Franklin.A. andB. alsoC. as well asD. so too10. It was from the Lowell Laboratory that the ninth ______, Pluto, was sighted in1930.A. planetB. constellationC. stardomD. satellite11 .The rodent, _______ the mouse, rat, guinea pig, and porcupine, are mammals withincisor-like teeth in both jaws.A. made upB. includingC. consistingD. constitute12. ______ into oceans and rivers is a serious form of pollution.A. Pouring sewageB. Emptying litterC. Throwing garbageD. Dumping sewage13. Products which are made from dirts and are _____ high temperatures are knownas ceramics.A. tempered inB. subjected toC. exposed toD. baked in14. A pigment called melanin protects the _____ layers of skin from sun rays.A. underB. belowC. underlyingD. underneath15. Oranges are a ______ source of vitamin C.A. wellB. betterC. goodD. very16. Even after having their grandchildren live with them for ten years, the couple feltthat ______ children these days was the most difficult of all family matters.A. risingB. raisingC. caringD. taking care17. The most important ______ of the farmers in Iraq is dates, of which Iraq is theworld's leading exporter.A. economic cropB. cash cropC. money cropD. staple18. More has been learned about the Moon than any other of the Earth's neighbors inspace because of the Apollo program, which enabled men to walk on the Moon and bring back hundreds of pounds of _____.A. rocksB. rockC. stoneD. stones19. _____ the variety that the average family has in beef, fish, poultry, and vegetarianrecipes, they find most meals unexciting.A. InspiteB. InspiteC. Despite ofD. Despite20. The speaker _____ have criticized the paraprofessionals, knowing full well thatthey were seated in the audience.A. should not toB. must notC. ought not toD. may notPart 2 Vocabulary ReplacementThis part consists of 15 sentences in which one word or phrase is underlined. Below each sentence, there are four choices respectively marked by letters A, By C and D. Choose the word or phrase that can replace the underlined part without causing any grammatical error or changing the basic meaning of the sentence. There is only ONE right answer. Blacken the corresponding letter with a single bar across the square brackets on your Machine-scoring ANSWER SHEET.21. Iceland has the oldest parliament, which goes as far back to 930 A. D. whenAlthing, the legislative organization, was established.A. officeB. adobeC. assemblyD. building22. The only problem with the debate last week was that the beginning sounded morelike a personal attack than a dispassionate, intellectual arguing.A. discussionB. argumentC. talkD. speech23. Susan Jones was at the bus stop well on time to take the 7:01 bus, but she had tomiss her breakfast to do it.A. catch up withB. catchC. run up toD. be catching24. Since her father could not drive her to the airport, she requested her uncle to driveher instead.A. takeB. bringC. dispatchD. deliver25. A famous collection of Persian, Indian, and Arabian folktales, the Arabian Nightswas supposedly told by the legendary queen Scheherazade to her husband every night for 1,001 days.A. imaginaryB. imageryC. fabledD. legend26. What may be the oldest fossil footprint yet found was discovered in June 1968 byWilliam J. Meister, a non-professional fossil collector.A. a part-timeB. a spare-timeC. an untrainedD. an amateur27. Most of us think of sharks as dangerous, owing to lack of information rather thanfear.A. due toB. becauseC. asD. for28. Double Eagle D, the first trans-Atlantic balloon, was greeted by avid crowds inFrance.A. eagerB. surgingC. appreciativeD. vigorous29. The discovery of the connection between aspirin and Reyessyndrome, a rare anddeadly ailment, is a recent example of the caution with which drugs must be used, even for medical purposes.A. diseaseB. sickC. illD. illness30. My parents moved out of their old home sometime last year after they hadcelebrated their 50th year there.A. anniversaryB. years oldC. ageD. wedding31. The library she worked in lent books, magazines, audio-cassettes and maps to itscustomers, who could keep them for four weeks.A. borrowersB. lendersC. patronsD. clients32. A common question that people ask a story writer is whether or not he hasexperienced what he has written about.A. fictionB. scienceC. imaginaryD. literary33. At the World literacy Center, an organization that works to help people read, thehelpers work hard, enabling them to successfully reach their goals.A. assistantsB. volunteersC. part-timersD. amateurs34. The officers made it clear that they were letting her go only because that she wasold and not because she was above suspicion.A. for reasonB. due toC. because ofD. on the grounds35. The book, which is a useful guide for today's young people, deals with manyquestions and problems that face them at school and at home as well as in society.A. are facedB. confrontC. in oppositionD. meetPart 3 Error CorrectionThis part consists of 75 sentences in which there is an underlined part that indicates a grammatical error. Below each sentence, there are four choices respectively marked by letters A, B, C and D. Choose the word or phrase that can replace the underlined part so that the error is corrected. There is only ONE right answer. Blacken the corresponding letter with a single bar across the square brackets on your Machine-scoring ANSWERSHEET.36. All don't have a free ticket must pay the admission fee.A. Everyone who doesn't have a free ticketB. No one who doesn't have a free ticketC. No one who has free ticketsD. Anyone who has free tickets37. When I last saw them, the police had chased the robbers down Columbus Street.A. were chasingB. was chasingC. chasedD. were on a chase38. Erosion that is a slow process, but it constantly changes the features on the surfaceof the earth.A. which isB. althoughC. beingD. is39. When an organism is completely encapsulated and preserved, it becomes a fossil,therefore turning into evidence of things that once lived.A. therebyB. as a result ofC. soD. in the end40. The pictures of the Loch Ness Monster show a remarkable resemblance to aplesiosaur, a large water reptile of the Mesozoic era presuming extinct for more than 70 million years.A. supposedB. presumablyC. presumptuousD. is presumed41. In our own galaxy, the Milky Way, there are perhaps 200 billion stars, a small partof them probably have planets on which life is feasible.A. a small fraction in whichB. a small fraction of whichC. a small fraction whichD. which a fraction of42. "But you'll be able to come, won’t you?" "Yes, I think such."A. thatB. itC. soD. this43. The professor is quite difficult pleased.A. to pleaseB. to be pleasedC. for pleasingD. pleasing44. Because everyone knows, facts speak louder than words.A. SinceB. ThatC. ItD. As45. The trapeze artist who ran away with the clown broke up the lion tamer's heart.A. broke awayB. broke downC. brokeD. broken down46. His heavy drinking and fond of gambling makes him a poor role model.A. and fact that he gamblesB. and that he gamblesC. and he gambles whichD. and gambling47. Depression that inflicts people who believe their lives lack content when the rushof the busy week stops referred to by a prominent psychiatrist as Sunday Neurosis.A. has been referred to by a prominent psychiatristB. has been referred to as by a prominent psychiatristC. a prominent psychiatrist has referred to itD. it has been referred to by a prominent psychiatrist48. Just as there are occupations that require college degrees also there areoccupations for which technical training is necessary.A. so to there areB. so too there areC. so there areD. so too are there49. Most of the older civilizations which flourished during the fifth century B. C. aredied out.A. they have died outB. has died outC. have died outD. they had died out50. The student asked her professor if he would have gone on the spaceship he didknow earlier.A. if he knewB. if he knowsC. he had knownD. had he known Section 2 Reading Comprehension (55 points)In this section you will find after each of the passages a number of questions or unfin-ished statements about the passage, each with four (A, B, C and D) choices to com-plete the statement. You must choose the one which you think fits best. Then blacken the corresponding letter with a single bar across the square brackets on your Machine-scoring ANSWER SHEET.Passage OneQuestions 51 - 56 are based on die following passage.Awarded the Nobel Prize for physics in 1918, German physicist Max Planck is best remembered as the originator of the quantum theory. His work helped usher in a new era in theoretical physics and revolutionized the scientific community’s understanding of atomic and subatomic processes.Planck introduced an idea that led to the quantum theory, which became the foundation of twentieth century physics. In December 1900, Planck worked out an equation that described the distribution of radiation accurately over the range of low to high frequencies. He had developed a theory which depended on a model of matter that seemed very strange at the time. The model required the emission of electromagnetic radiation in small chunks or particles. These particles were later called quantums. The energy associated with each quantum is measured by multiplying the frequency of the radiation, v, by a universal constant, h. Thus, energy, or E, equals hv. The constant, h, is known as Planck's constant. It is now recognized as one of the fundamental constants of the world.Planck announced his findings in 1900, but it was years before the full consequences of his revolutionary quantum theory were recognized. Throughout his life, Planck made significant contributions to optics, thermodynamics and statistical mechanics, physical chemistry, among other fields.51. In which of the following fields did Max Planck NOT make a significantcontribution?A. Optics.B. Thermodynamics.C. Statistical mechanics.D. Biology.52. The word "revolutionary" as used in Line 15 means_.A. radicalB. extremistC. momentousD. militaristic53. It can be inferred from the passage that Planck’s work led to the development of________.A. The rocketB. The atomic bombC. The internal combustion engineD. The computer54. The particles of electromagnetic radiation given off by matter are known as ____.A. quantumsB. atomsC. electronsD. valences55. The implication in this passage is that ______.A. only a German physicist could discover such a theoryB. quantum theory, which led to the development of twentieth century physics, isbasically a mathematical formulaC. Planck's constant was not discernible before 1900D. radiation was hard to study56. ―An idea‖ as used in line 5, refers to _____.A. a model of matterB. emission of electromagnetic radiationC. quantumsD. the equation that described the distribution of radiation accurately over the range of low to high frequenciesPassage TwoQuestions 57 ~ 62 are based on the following passage.There has been much speculation about the origin of baseball. In 1907 a special commission decided that the modern game was invented by Abner Doubleday in 1839. One hundred years later the National Baseball Museum was opened to honor Doubleday. Historians, however, disagree about the origin of baseball. Some say that baseball comes from bat-and-ball games of ancient times. It is a matter of record that in the 1700s English boys played a game they called ―baseball‖. Americans have played a kind of baseball since about 1800. At first the American game had different rules and different names in various parts of the country —―town ball‖, ―rounders‖, or ―one old cat‖. Youngsters today still play some of these simplified forms of the game.Baseball did not receive a standard set of rules until 1845, when Alexander Cartwright organized the Knickerbocker Baseball Club of New York City. The rules Cartwright set up for his nine-player team were widely adopted by other clubs and formed the basis of modern baseball. The game was played on a "diamond" infield with the bases 90 feet apart. The first team to score 21 runs was declared the winner. By 1858 the National Association of Baseball Players was formed with 25 amateur teams. The Cincinnati Red Stockings began to pay players in 1869.57. Which of the following is true about the origins of baseball?A. Historians agree that baseball was invented by Abner Doubleday.B. Baseball, as played in the early 19th century, differed very little from today'sgame.C. As early as the 1700s, English boys played a game called "baseball".D. The first standard set of baseball rules was established at the turn of the century.58. What was the first professional baseball team called?A. New York Knickerbockers.B. Milwaukee Braves.C. Cincinnati Red Stockings.D. Brooklyn Dodgers.59. Who first gave baseball a standard set of rules?A. Abner Doubleday.B. Alexander Cartwright.C. Albert Spalding.D. Babe Ruth.60. Which of the followings was not a predecessor of baseball?A. Rounders.B. Town ball.C. Cricket.D. One old cat.61. The tone of the passage is ______.A. persuasiveB. informativeC. biasedD. argumentative62. The passage implies that until 1869, baseball was played for all of the followingreasons except _______.A. exerciseB. leisureC. profitD. socializingPassage ThreeQuestions 63-68 are based on the following passage.The blue of the sea is caused by the scattering of sunlight by tiny particles suspended in the water. Blue light, being of short wavelength, is scattered more efficiently than light of longer wavelengths. Although waters of the open ocean are commonly some shade of blue, green water is commonly seen near coasts, especially in tropical or subtropical regions. This is caused by yellow pigments being mixed with blue water. Phytoplankton are one source of the yellow pigment. Other microscopic plants may color the water brown or brownish-red. Near the shore, silt or sediment in suspension can give water a brownish hue. Outflow of large rivers can often be observed many miles offshore by the coloration of suspended soil particles.Marine phytoplankton (Greek for "plant wanderers") are microscopic single-celled plants that include diatoms, dinoflagellates, coccolithophorids, green algae, and blue-green algae, among others. The growth of these organisms, which photogynthesize light, depends on a delicate balance of nutrient enrichment via vertical mixing, which is often limited by the availability of nitrogen and light. Diatoms are one-celled plants with patterned glass coverings. Each glass, or silicon dioxide box, is ornamented with species-specific designs, pits, and perforations making them popular with microscopists and, more recently, electron scanning microscopists.63. Green water near coastlines is almost always caused by _____.A. sand colorB. red pigments in coastal watersC. blue pigmentD. reflected light and yellow pigment from plant life64. Phytoplankton are the source of which color pigment?A. Red.B. Green.C. Yellow.D. Blue.65. What can give waters a brownish hue near the shore?A. Sediment.B. Phytoplankton.C. Blue pigment.D. Diatoms.66. Which of the following is NOT a type of phytoplankton?A. Green algae.B. Diatoms.C. Blue-green algae.D. Amoeba.67. The growth of phytoplankton is often limited by the availability of _____.A. oxygenB. hydrogenC. nitrogenD. carbon dioxide68. The main idea of this passage is that _____.A. light causes sea colorB. sea coloration is varied because of a combination of length of light waves andmicroscopic plant life and siltC. microscopic plant life causes sea colorD. water composition causes sea colorPassage FourQuestions 69 - 75 are based on the following passage.The United States government publishes guidelines for appropriate nutrient intakes. These are known as the Recommended Dietary Allowances (RDAs) and are updated regularly based on new research in nutrition. RDAs are suggested amounts of calories, protein, and some minerals and vitamins for an adequate diet. For other dietary substances, specific goals must await further research. However, for the U.S. population as a whole, increasing starch and fiber in one's diet and reducing calories (primarily from fats, sugar, and alcohol) is sensible. These suggestions are especially appropriate for people who have other factors for chronic diseases due to family history of obesity, premature heart disease, diabetes, high blood pressure, and high blood cholesterol, or for those who use tobacco.Snacks can furnish about one-fourth of the calorie requirements among teenagers. Those snacks should also provide much of the day's allowances for protein, minerals, and vitamins. Sandwiches, fruit, and milk make good snacks for active teenagers. Food from the food pyramid may be part of any meal. A grilled cheese sandwich or a bowl of whole-grain cereal is just as nutritious in the morning as it is at noon. In addition, a good breakfast consists of any foods that supply about one-fourth of the necessary nutrients for the day.69. The passage directly states that most of the U. S. population should increase theirintake of ______.A. proteinB. fatsC. starch and fiberD. sandwiches70. A good breakfast should supply about what percentage of the necessary nutrientsfor the day?A. One-half.B. One-third.C. One-fourth.D. Less than one-fourth.71. The passage implies which of the following?A. The rime of day when food is consumed affects its nutritive value.B. Different foods can be combined to increase total nutrition value.C. It can be detrimental to your health to eat breakfast foods later in the day.D. When food is eaten has no bearing on its nutritive effects.72. Why are RDAs regularly updated?A. New discoveries in the science of nutrition are constantly being made.B. Americans' diets are constantly changing.C. As people age, their nutritional needs change.D. Very little is currently known about nutrition.73. In this passage RDAs refers to___.A. types of vitaminsB. types of proteinC. types of mineralsD. amounts of energy, protein, vitamins, and minerals74. One implication in this passage is that _____.A. all RDAs have been establishedB. not all RDAs have been established yetC. it's not important to know RDAsD. RDAs are necessary only for sick people75. The reduction of calories in the diet is particularly good for people who sufferfrom ________.A. obesityB. premature heart disease and diabetesC. high blood pressure and cholesterol levelsD. all of the abovePassage FiveQuestions 76 - 81 are based on the following passage.The most popular organic gem is the pearl. A pearl is the response of a marine mollusk to the presence of an irritating impurity accidentally introduced into its body;a cultured pearl is the result of the intentional insertion of a mother-of-pearl bead into a live mollusk. Whether introduced accidentally or intentionally, the pearl-making process is the same: the mollusk coats the irritant with a substance called nacre. Nacre is composed chiefly of calcium carbonate. Because very few natural pearls are now on the market, most pearls used in fine jewelry are cultured. These include "Biwa" pearls and most other freshwater pearls. Cultured pearls are not easily distinguished from natural pearls except by an expert.76. Which of the following people could tell the difference between a cultured pearland an organic pearl?A. Scuba diver.B. Fisherman.C. Jeweler.D. Clerk.77. What is the chief component of nacre?A. Sand.B. Bead.C. Calcium carbonate.D. Biwa.78. The difference between a pearl and a cultured pearl is the nature of the ____.A. colorB. introduction of the irritating impurityC. coating materialD. irritating impurity79. Nacre is a substance that is ______.A. mechanically manufacturedB. the result of laboratory testingC. organically secreted by the molluskD. present in the chemical composition of freshwater pounds80. The main idea of this passage is that ______.A. most marketable pearls are cultured because nature does not produce enough ofits own to satisfy the marketB. cultured pearls are of a higher quality than natural pearlsC. there are two major methods of pearl-makingD. a natural ―drought‖ of pearl production is taking place81. Cultured pearl is formed by ____.A. insertion of a pearl into a live molluskB. an oyster into which a piece of grit has been placedC. putting in a live molluskD. placing a bead into culturePassage SixQuestions 82-87 are based on the following passage.Stress is with us all the time. It comes from mental or emotional activity as well as physical activity. It is unique and personal to each of us. So personal, in fact, that what may be relaxing to one person may be stressful to another. For example, if you're a busy executive who likes to keep occupied all of the time, "taking it easy" at the beach on a beautiful day may be extremely frustrating, nonproductive, and upsetting. You may be emotionally distressed from "doing nothing." Too much emotional stress can cause physical illnesses such as high blood pressure, ulcers, or even heart disease. Physical stress from work or exercise is not likely to cause such ailments. The truth is that physical exercise can help you to relax and to better handle your mental or emotional stress.82. Which of the following people would find ―taking it easy‖ stressful?A. Construction workers.B. Business executives.C. Farm workers.D. Truck drivers.83. Which of the following would be a determinant as to what people find stressful?A. Personality.B. Education.C. Marital status.D. Shoe size.84. This article, published by the Department of Health and Human Services,probably came from the ______.A. Federal Bureau of InvestigationB. Alcohol, Drug Abuse, and Mental Health AdministrationC. Education AdministrationD. Communicable Diseases Administration85. A source of stress NOT specifically mentioned in this passage is _____.A. educational activityB. physical activityC. mental activityD. emotional activity86. Physical problems caused by emotional stress can appear as all of the followingEXCEPT _____.A. ulcersB. pregnancyC. heart diseaseD. high blood pressure87. One method mentioned to help handle stress is ____.A. physical exerciseB. tranquilizersC. drugsD. taking it easy Passage SevenQuestions 88 ~ 92 are based on the following passage.With the sudden onset of severe psychotic symptoms, the individual is said to be experiencing acute schizophrenia (精神分裂症) - "Psychotic" means out of touch with reality, or unable to separate real from unreal experiences. Some people have only one such psychotic episode. Others have many episodes during a lifetime but lead relatively normal lives during interim periods. The individual with chronic (continuous or recurring) schizophrenia often does not fully recover normal functioning and typically requires long-term treatment, generally including medication, to control the symptoms. These symptoms may include hallucinations (幻觉), incoherence, delusions, lack of judgment, deterioration of the abilities to reason and feel emotion, and a lack of interaction between the patient and his environment. The hallucinations may be a visual, auditory, or tactile. Some chronic schizophrenic patients may never be able to function without assistance of one sort or another.88. Which of the following is not a symptom of schizophrenia?A. Hallucinations.B. Delusions.C. Incoherence.D. Vertigo.89. It can be inferred from the passage that a person experiencing acute schizophreniamost likely ______.A. cannot live without medicationB. cannot go on livingC. can hold a full-time jobD. cannot distinguish real from unreal90. According to this passage, thinking that one can fly might be an example of ____.A. medicine overdoseB. being out of touch with realityC. recovering normal functioningD. symptom control91. The passage suggests that the beginning of severe psychotic symptoms of acuteschizophrenia may be any of the following EXCEPT_____.A. debilitatingB. sudden occurrenceC. occurring after a long period of normalcyD. drug-induced92. The passage implies that normal life may be possible for the chronicschizophrenic with the help of ______.A. medicinesB. neurotic episodesC. psychotic episodesD. time Passage EightQuestions 93 ~ 100 are based on the following passage.Aspirin is one of the safest and most effective drugs invented by man. The most popular medicine in the world today, it is an effective pain reliever. Its bad effects are relatively mild. It is also cheap.For millions of people suffering from arthritis, it is the only thing that works. Aspirin, in short, is truly the 20th-century wonder drug. It is also the second largest suicide drug and is the leading cause of poisoning among children. It has side effects that, although relatively mild, are largely unrecognized among users.Although aspirin was first sold by a German company in 1899, it has been around much longer than that. Hippocrates, in ancient Greece, understood the medical value of tree barks and leaves which today are known to contain a chemical found in aspirin. During the 19th century, there was a great deal of experimentation in Europe with this。

碳包覆的磁性纳米材料萃取酞酸酯

第３２卷㊀第１２期２０１３年㊀㊀１２月环㊀境㊀化㊀学ＥＮＶＩＲＯＮＭＥＮＴＡＬＣＨＥＭＩＳＴＲＹＶｏｌ．３２，Ｎｏ．１２Ｄｅｃｅｍｂｅｒ２０１３㊀２０１３年３月２７日收稿．㊀∗国家自然科学基金（２１２０７０５９，２１１７１０８５）；山东省自然科学基金（ＺＲ２０１０ＢＭ０２７，ＺＲ２０１１ＢＱ０１２）资助．㊀∗∗通讯联系人，Ｔｅｌ：１３８６４５９３６９８；Ｅ⁃ｍａｉｌ：ｌｄｕｚｓｘ＠１２６．ｃｏｍＤＯＩ：１０．７５２４／ｊ．ｉｓｓｎ．０２５４⁃６１０８．２０１３．１２．００３碳包覆的磁性纳米材料萃取酞酸酯∗王颖辉１㊀腾㊀飞２㊀张媛媛３㊀张升晓３∗∗㊀刘军深３㊀吴㊀茜３（１．烟台开发区城市管理环保局，烟台，２６４００６；㊀２．上海通用东岳汽车有限公司，烟台，２６４００６；３．鲁东大学，烟台，２６４０２５）摘㊀要㊀利用水热反应制备碳材料包覆的Ｆｅ３Ｏ４（Ｆｅ３Ｏ４／Ｃ）纳米颗粒，并将这种材料用作固相萃取吸附剂，从环境水样中富集酞酸酯类（ＰＡＥｓ）污染物．由于纳米材料大的比表面积和碳材料强的吸附能力，Ｆｅ３Ｏ４／Ｃ吸附剂拥有较高的萃取效率．从５００ｍＬ的环境水样中定量萃取ＰＡＥｓ目标物，只需５０ｍｇ的吸附剂．ＰＡＥｓ在Ｆｅ３Ｏ４／Ｃ表面的吸附可快速达到平衡，并且用少量的乙腈就能将分析物洗脱下来．在优化的固相萃取条件下，几种ＰＡＥｓ的检出限在１７５８ｎｇ㊃Ｌ－１之间．通过水样的加标回收率来评价该方法，其加标回收率在９４．６％１０６．６％之间，相对标准偏差为２％８％．关键词㊀酞酸酯，磁性固相萃取，碳材料．酞酸酯类化合物（ＰＡＥｓ）作为增塑剂用于塑料制品的生产，来提高塑料强度和增大可塑性．这类物质会从塑料制品中迁移转化进入环境，从而对环境造成污染．ＰＡＥｓ具有三致（致突㊁致畸㊁致癌）作用，属于环境内分泌干扰物，其中有６种化合物已被美国国家环保局列为优先监控污染物［１］．目前测定水体ＰＡＥｓ的前处理方法主要有液液萃取［２］㊁固相萃取［３］㊁固相微萃取［４］等方法．李玫瑰等［５］以甲苯为萃取溶剂，采用微滴液相微萃取方法快速分析水溶性食品中的ＰＡＥｓ．王东新［６］以中空纤维膜液相微萃取方法从天然水体中萃取了４种ＰＡＥｓ，并结合气相色谱进行分析．胡庆兰［７］采用自制的固相微萃取涂层，通过顶空固相微萃取与气相色谱法联用测定水中的ＰＡＥＳ．固相萃取法以有机溶剂消耗少㊁操作简便等优点被广泛采用．王鑫等［８］采用Ｃ１８小柱萃取饮用水和自来水中的４种ＰＡＥｓ类污染物，并用气相色谱法测定．陈永山等［９］研究了流速和除水方式等条件对Ｃ１８固相萃取柱富集ＰＡＥｓ回收率的影响，他们还用罗里硅土净化土壤提取液，测定了土壤中的１１种ＰＡＥｓ类污染物［１０］．纳米材料拥有大的比表面积和短的扩散路径，使其具有很高的萃取效率和较快的吸附速度，近年来被开发研究用作固相萃取吸附剂，从环境或生物样品中富集污染物［１１⁃１２］．然而纳米材料填充的固相萃取小柱具有很大的反压，样品通过小柱需要消耗大量的时间．因此，磁性纳米材料用作固相萃取吸附剂的研究应运而生［１３⁃１５］，张小乐等［１６］合成了Ｃ１８基团修饰的磁性介孔硅胶材料，并利用该材料建立了磁性固相萃取⁃色谱分析方法，测定了环境水样中ＰＡＥｓ污染物的含量．我们以前的研究［１７⁃１９］表明，在基于磁性纳米颗粒的固相萃取方法中，可将经过修饰的磁性纳米材料分散到样品中进行目标物吸附，达到吸附平衡后，利用磁铁快速将吸附了目标物的磁性材料分离出来，然后将目标物进行洗脱㊁测定，该快速磁分离方法避免了传统固相萃取中耗时的过柱操作，能够节省大量时间．本文制备了一种新型的磁性纳米材料（Ｆｅ３Ｏ４／Ｃ），并以该纳米材料为固相萃取吸附剂从环境水样中富集ＰＡＥｓ污染物．优化了吸附剂用量㊁平衡时间㊁盐度㊁ｐＨ㊁解吸附等固相萃取条件，并将这种新型的固相萃取技术与高效液相色谱（ＨＰＬＣ）结合，开发了一种分析环境水体中ＰＡＥｓ的新方法．１㊀实验部分１．１㊀化学试剂和材料㊀㊀酞酸丙酯（ＤＰＰ）㊁酞酸丁酯（ＤＢＰ）㊁酞酸环己酯（ＤＣＰ）和酞酸辛酯（ＤＯＰ）标准样品从美国Ａｃｒｏｓ２２４４㊀环㊀㊀境㊀㊀化㊀㊀学３２卷Ｏｒｇａｎｉｃｓ公司购得．十八烷基三乙氧基硅烷购买自日本东京化学试剂公司．ＦｅＣｌ３㊃４Ｈ２Ｏ和ＦｅＣｌ２㊃６Ｈ２Ｏ从北京化学试剂公司购买．葡萄糖购买自北京红星化学公司．色谱纯的甲醇和乙腈购自美国的ＴｈｅｒｍｏＦｉｓｈｅｒ公司．实验用的纯水来自于美国Ｍｉｌｌｉ⁃Ｑ纯水系统．１．２㊀Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ纳米材料的制备和表征采用化学共沉淀的方法制备Ｆｅ３Ｏ４磁性纳米材料．首先将２．０ｇＦｅＣｌ２㊃４Ｈ２Ｏ和５．２ｇＦｅＣｌ３㊃６Ｈ２Ｏ溶解到２５ｍＬ的预先脱氧的去离子水，再加入０．８５ｍＬ浓盐酸．将以上溶液逐滴加到２５０ｍＬ１．５ｍｏｌ㊃Ｌ－１的ＮａＯＨ溶液，边加边机械搅拌并通氮气保护．反应完成后，生成的黑色Ｆｅ３Ｏ４纳米颗粒用２００ｍＬ去离子水洗２次，再分散到１１０ｍＬ的去离子水中，悬浮液中Ｆｅ３Ｏ４纳米颗粒的浓度约为２０ｍｇ㊃ｍＬ－１．采用水热法在纳米Ｆｅ３Ｏ４的表面包覆一层碳材料．将０．４ｇＦｅ３Ｏ４用去离子水冲洗，直至溶液为中性，然后分散到８０ｍＬ０．５ｍｏｌ㊃Ｌ－１的葡萄糖溶液中，将此混合物超声２０ｍｉｎ后转移到聚四氟乙烯内衬的反应釜中．将反应釜在１８０ħ加热４ｈ，反应完成后，用磁铁将Ｆｅ３Ｏ４／Ｃ纳米材料分离，再用去离子水和乙醇冲洗几次除去杂质．最后将反应产物分散到７０ｍＬ的去离子水中得到１０ｍｇ㊃ｍＬ－１的Ｆｅ３Ｏ４／Ｃ．利用透射电镜（ＴＥＭ，Ｈ⁃７５００，Ｈｉｔａｃｈｉ，Ｊａｐａｎ）观察制得的吸附材料的形貌和粒径，工作电压为８０ｋＶ．材料的能谱图（ＥＤＳ）采用Ｓ⁃３０００Ｎ能谱仪（Ｈｉｔａｃｈｉ，Ｊａｐａｎ）测定．材料的红外谱图采用ＫＢｒ压片的方式在ＮＥＸＵＳ６７０傅立叶变换红外光谱仪（ＮｉｃｏｌｅｔＴｈｅｒｍｏ，Ｕ．Ｓ．）采集．１．３㊀固相萃取的程序将５０ｍｇ的Ｆｅ３Ｏ４／Ｃ吸附剂分散到５００ｍＬ水样中，搅拌２０ｓ使吸附剂在溶液中均匀分散．将１个Ｎｄ⁃Ｆｅ⁃Ｂ强力磁铁置于容器底部进行磁分离．经过大约１０ｍｉｎ，溶液变清澈，吸附剂被完全分离到容器底部，将上清液倒掉．在吸附剂中加入２ｍＬ乙腈，超声１０ｓ后置于磁铁上分离，洗脱液转移到离心管中，取２０μＬ进ＨＰＬＣ系统测定．由于塑料制品可能会释放出ＰＡＥｓ，因此在实验过程中使用玻璃容器．１．４㊀ＨＰＬＣ分析利用美国安捷伦公司的高效液相色谱系统对ＰＡＥｓ进行分离和分析，迪马Ｃ１８色谱柱（２５０ˑ４．６ｍｍ，粒径５μｍ），采用梯度淋洗的方法分离，５０％的乙腈水溶液和纯乙腈分别为流动相Ａ和Ｂ，流速为１ｍＬ㊃ｍｉｎ－１．梯度淋洗程序如下：前１５ｍｉｎ内Ｂ保持在４０％，在１０ｍｉｎ内Ｂ由４０％升至１００％，保持１０ｍｉｎ，随后在３ｍｉｎ内回到初始状态．ＰＡＥｓ采用紫外检测器测定，波长设在２２６ｎｍ．２㊀结果与讨论２．１㊀吸附剂的表征图１为Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ的透射电镜图片．Ｆｅ３Ｏ４纳米颗粒为近似球形，粒径分布比较均匀，平均直径大约为１０ｎｍ．Ｆｅ３Ｏ４／Ｃ纳米颗粒呈现出明显的核壳结构，内层颜色较深的为Ｆｅ３Ｏ４核，而外层颜色相对较浅的部分是碳层．Ｆｅ３Ｏ４核使得材料具有磁性，而碳包覆层赋予材料强的吸附能力．图１㊀Ｆｅ３Ｏ４（ａ）和Ｆｅ３Ｏ４／Ｃ（ｂ）纳米材料的透射电镜图（放大倍数：２０００００）Ｆｉｇ．１㊀ＴＥＭｉｍａｇｅｓｏｆＦｅ３Ｏ４（ａ），ａｎｄＦｅ３Ｏ４／Ｃ（ｂ）ｎａｎｏｐａｒｔｉｃｌｅ㊀１２期王颖辉等：碳包覆的磁性纳米材料萃取酞酸酯２２４５㊀Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ的能谱图见图２．在Ｆｅ３Ｏ４纳米颗粒的能谱图中只有一个很小的碳峰，在其表面包覆一层碳材料后，Ｆｅ３Ｏ４／Ｃ的能谱图中出现了一个较大的碳峰，其表面碳元素的摩尔百分含量达到５４４％，而铁元素的摩尔百分含量降低到１３．８％，说明碳材料被成功的包覆到了Ｆｅ３Ｏ４纳米颗粒表面．图２㊀Ｆｅ３Ｏ４（ａ）和Ｆｅ３Ｏ４／Ｃ（ｂ）纳米材料的能谱图Ｆｉｇ．２㊀ＥＤＳｓｐｅｃｔｒａｏｆＦｅ３Ｏ４（ａ）ａｎｄＦｅ３Ｏ４／Ｃ（ｂ）ｎａｎｏｐａｒｔｉｃｌｅ利用傅立叶变换红外光谱分析Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ材料的表面基团．由图３可见，Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ的红外谱图上都有１个５８０ｃｍ－１的吸收峰，为Ｆｅ３Ｏ４的特征吸收峰［２０］．在Ｆｅ３Ｏ４／Ｃ的谱图上１７００ｃｍ－１和１６１６ｃｍ－１的峰是ＣＯ和ＣＣ的振动吸收峰［２１］，这表明在水热反应的过程中，葡萄糖碳化包覆到了纳米Ｆｅ３Ｏ４的表面．１０００１３００ｃｍ－１的峰是ＣＯＨ的伸缩振动峰和ＯＨ弯曲振动峰［２２］，３１００３７００ｃｍ－１之间的宽峰是ＯＨ伸缩振动峰［２３］．Ｆｅ３Ｏ４／Ｃ纳米材料的表面上羟基和羧基基团的存在使得该材料具有表面亲水性，能够在水溶液中分散和稳定存在，并且材料的表面亲水性降低了分析物在其表面的不可逆吸附，能够在一定程度上克服碳材料用作固相萃取洗脱困难的缺点．２．２㊀萃取条件的优化２．２．１㊀吸附剂用量的选择为了获得最优的目标物回收率，在０１００ｍｇ的范围改变Ｆｅ３Ｏ４／Ｃ吸附材料的加入量进行萃取，其结果列于图４．随Ｆｅ３Ｏ４／Ｃ吸附剂加入量的增加，ＰＡＥｓ的回收率也逐渐增加，当吸附剂用量为４０ｍｇ时，ＰＡＥｓ的回收率达到最大值，吸附剂的用量继续增加，回收率基本保持平衡，不会再有明显的增加．使用没有修饰的Ｆｅ３Ｏ４作为固相萃取的吸附剂，即使其用量达到１００ｍｇ，对ＰＡＥｓ的回收率也不会超过１０％．图３㊀Ｆｅ３Ｏ４和Ｆｅ３Ｏ４／Ｃ纳米材料的红外谱图Ｆｉｇ．３㊀ＩＲｓｐｅｃｔｒａｏｆＦｅ３Ｏ４ａｎｄＦｅ３Ｏ４／Ｃｎａｎｏｐａｒｔｉｃｌｅ图４㊀吸附剂用量对ＰＡＥｓ回收率的影响Ｆｉｇ．４㊀ＥｆｆｅｃｔｏｆｔｈｅａｍｏｕｎｔｏｆＦｅ３Ｏ４／ＣｓｏｒｂｅｎｔｏｎｔｈｅｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙｏｆＰＡＥｓ㊀㊀结果表明，能够有效吸附ＰＡＥｓ的是Ｆｅ３Ｏ４／Ｃ材料表面的碳层．碳纳米管和有机化合物之间的吸附主要通过疏水作用，π⁃π键㊁氢键作用和静电作用［２４］，Ｆｅ３Ｏ４／Ｃ纳米颗粒表面也是碳材料，因此其相互２２４６㊀环㊀㊀境㊀㊀化㊀㊀学３２卷作用机理相同．要达到满意的回收率只需要Ｆｅ３Ｏ４／Ｃ吸附剂４０ｍｇ，可能是因为Ｆｅ３Ｏ４／Ｃ材料拥有大的比表面积和碳材料的强吸附能力．为保证分析物的完全吸附，在水样中加入５０ｍｇ的Ｆｅ３Ｏ４／Ｃ纳米吸附剂．２．２．２㊀乙腈用量和平衡时间的选择选用乙腈从Ｆｅ３Ｏ４／Ｃ吸附剂上解吸ＰＡＥｓ．为了能够将ＰＡＥｓ充分解吸附，将Ｆｅ３Ｏ４／Ｃ吸附剂在洗脱液中超声２０ｓ再分离．由图５（ａ）可以看出，只需１ｍＬ乙腈就可将８０％以上的目标物解吸下来，增加乙腈的用量，ＰＡＥｓ的回收率略有增加，但影响不大，本实验选用２ｍＬ乙腈作为洗脱剂．传统的碳材料用作固相萃取吸附剂时，常常面临洗脱困难的问题［２５］．而本研究中Ｆｅ３Ｏ４／Ｃ材料较易洗脱，一方面可能是因为包覆在纳米材料上的薄层碳使得分析物的扩散路径较短，便于洗脱，另一方面可能是因为包覆上的碳材料表面是亲水性，有效避免了分析物在其上发生不可逆吸附．Ｆｅ３Ｏ４／Ｃ是超顺磁性并且拥有大的饱和磁强度，但由于其在水溶液中分散良好且表面羧基使颗粒之间存在静电斥力，因此从纯水中用磁铁分离需要较长时间．为了帮助磁分离，在水溶液中加入２ｍＬ１ｍｏｌ㊃Ｌ－１的ＮａＣｌ溶液提供补偿离子．用一个Ｎｄ⁃Ｆｅ⁃Ｂ强力磁铁能在１０ｍｉｎ将吸附剂完全吸附到容器的底部．通常要达到完全吸附目标物和吸附剂要有充分的接触时间．改变平衡时间考察目标物回收率的变化，由图５（ｂ）可以看出，随着平衡时间由０到１２０ｍｉｎ，ＰＡＥｓ的回收率没有明显变化，说明分析物能在很短的时间内完全吸附到Ｆｅ３Ｏ４／Ｃ材料上．这种快的吸附速率应归功于纳米材料短的扩散路径．磁性分离和快速的吸附，使这种新型固相萃取方法能够避免耗时的过柱操作，具有可操作性和实用性．图５㊀洗脱液乙腈用量（ａ）和平衡时间（ｂ）对ＰＡＥｓ回收率的影响Ｆｉｇ．５㊀Ｅｆｆｅｃｔｏｆａｃｅｔｏｎｉｔｒｉｌｅｖｏｌｕｍｅ（ａ）ａｎｄｓｔａｎｄｉｎｇｔｉｍｅ（ｂ）ｏｎｔｈｅｒｅｃｏｖｅｒｙｏｆＰＡＥｓ２．２．３㊀盐度和ｐＨ的选择为了考察盐度对ＰＡＨｓ回收率的影响，在溶液中加入ＮａＣｌ调整盐度．由图６（ａ）可以看出，在盐度为１５００ｍｍｏｌ㊃Ｌ－１的范围内，目标物的回收率基本不受影响，表明Ｆｅ３Ｏ４／Ｃ能从高盐度水样中萃取目标物而不受影响．吸附剂表面电荷的类型和密度通常会随溶液ｐＨ的改变而变化，因此溶液的ｐＨ可能会影响一些分析物在Ｆｅ３Ｏ４／Ｃ纳米材料上的吸附．改变溶液的ｐＨ值在３１０范围内考察其对ＰＡＨｓ萃取回收率的影响．由图６（ｂ）可以看出，在设定的ｐＨ范围内ＰＡＥｓ的回收率没有明显变化，说明Ｆｅ３Ｏ４／Ｃ纳米材料在此ｐＨ范围内比较稳定，不会被破坏，另一方面可能是因为ＰＡＥｓ在设定的条件以中性分子形式存在，材料表面电荷的改变对它们的吸附没有明显的影响．基于Ｆｅ３Ｏ４／Ｃ的磁性固相萃取方法无需严格控制溶液ｐＨ，用于环境水样品的分析更加便利和稳定．２．２．４㊀水样体积选择利用Ｆｅ３Ｏ４／Ｃ作吸附剂进行固相萃取，可以将材料分散在溶液中进行吸附，达到吸附平衡后用磁铁将吸附剂分离出来进行洗脱，该方法免去了耗时的过柱操作，因此非常适用于大体积环境水样的分析．如图７所示，利用５０ｍｇＦｅ３Ｏ４／Ｃ吸附剂，当水样的体积由２００ｍＬ增加到１０００ｍＬ时，ＰＡＨｓ的回收率没有明显下降，说明Ｆｅ３Ｏ４／Ｃ吸附材料具有大的穿透体积．通过从１０００ｍＬ水样中萃取目标物并将洗脱液浓缩到２ｍＬ，ＰＡＥｓ的富集系数可以达到５００倍．㊀㊀１２期王颖辉等：碳包覆的磁性纳米材料萃取酞酸酯２２４７图６㊀盐度（ａ）和溶液ｐＨ值（ｂ）对ＰＡＥｓ回收率的影响Ｆｉｇ．６㊀Ｅｆｆｅｃｔｏｆｓａｌｉｎｉｔｙ（ａ）ａｎｄｓｏｌｕｔｉｏｎｐＨ（ｂ）ｏｎｔｈｅｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙｏｆＰＡＥｓ图７㊀水样体积对ＰＡＥｓ回收率的影响Ｆｉｇ．７㊀ＥｆｆｅｃｔｏｆｗａｔｅｒｓａｍｐｌｅｖｏｌｕｍｅｏｎｔｈｅｒｅｃｏｖｅｙｏｆＰＡＥｓ２．３㊀分析方法相关参数固相萃取程序结合ＨＰＬＣ⁃ＵＶ检测建立了标准曲线，其线性范围为０．１２０ｎｇ㊃ｍＬ－１．从５００ｍＬ纯水样品中萃取目标物并用２ｍＬ溶剂洗脱，ＰＡＥｓ的富集系数为２５０倍．线性范围㊁线性相关系数和检出限等参数列于表１．由表１可以看出，该方法有较高的灵敏度㊁宽的线性范围和良好的精密度，ＰＡＥｓ的线性相关系数Ｒ２＞０．９９９．ＤＰＰ㊁ＤＢＰ㊁ＤＣＰ㊁ＤＯＰ的检出限（信噪比为３）分别为３５㊁５８㊁１７㊁３３ｎｇ㊃Ｌ－１．表１㊀标准曲线的方法参数Ｔａｂｌｅ１㊀Ａｎａｌｙｔｉｃａｌｐａｒａｍｅｔｅｒｓｏｆｔｈｅｐｒｏｐｏｓｅｄｍｅｔｈｏｄ分析物线性范围／（ｎｇ㊃ｍＬ－１）曲线方程线性相关系数（Ｒ２）方法检出限ａ／（ｎｇ㊃Ｌ－１）ＤＰＰ０．１２０ｙ＝０．５５７８ｘ＋０．０５６１０．９９９８３５ＤＢＰ０．１２０ｙ＝０．５４７６ｘ＋０．０６３４０．９９９７５８ＤＣＰ０．１２０ｙ＝０．９８６５ｘ－０．０３２７０．９９９７１７ＤＯＰ０．１２０ｙ＝０．５９４８ｘ＋０．１０３６０．９９９９３３㊀㊀ａ检测限根据信噪比为３确定（Ｓ／Ｎ＝３），ｘ为分析物浓度，ｙ为紫外信号强度．２．４㊀实际水样的测定实际水样选取实验室自来水和校园人工湖的湖水，采用所建立的磁性固相萃取方法测定水样中和加标后的水样中的ＰＡＥｓ，３次平行测定水样和加标水样结果平均值㊁加标水样的回收率平均值及标准偏差列于表２．自来水样中ＤＰＰ浓度为０．１０４ｎｇ㊃ｍＬ－１，其他未检出；湖水中ＤＰＰ和ＤＢＰ浓度分别为０２１５和０．１３２ｎｇ㊃ｍＬ－１，其余未检出．水样中低浓度的ＰＡＥｓ可能来自于塑料管路或者是塑料制品的释放．加标水样中ＰＡＥｓ的平均回收率在９４．６％１０６．６％之间，相对标准偏差为２％８％．图８为湖水样品及其加标色谱图，其峰型良好，基质相对比较干净，没有太多杂峰的干扰．２２４８㊀环㊀㊀境㊀㊀化㊀㊀学３２卷表２㊀实际水样中ＰＡＥｓ的浓度及其加标回收结果Ｔａｂｌｅ２㊀ＣｏｎｃｅｎｔｒａｔｉｏｎｓｏｆＰＡＥｓｉｎｒｅａｌｗａｔｅｒｓａｍｐｌｅｓａｎｄｒｅｃｏｖｅｒｉｅｓｏｆｓａｍｐｌｅｓｓｐｉｋｅｄｗｉｔｈａｎａｌｙｔｅｓ水样加标／（ｎｇ㊃ｍＬ－１）测定值ａ／（ｎｇ㊃ｍＬ－１）ＤＰＰＤＢＰＤＣＰＤＯＰ回收率ʃ相对标准偏差／％ｂＤＰＰＤＢＰＤＣＰＤＯＰ０．０００．１０４ｎｄｃｎｄｎｄ自来水０．５０．６１２０．５０４０．５２４０．５３３１０１．６ʃ３１０１．０ʃ２１０４．８ʃ６１０６．６ʃ８５５．１５５．１０４．８６４．７９１００．９ʃ２１０２．０ʃ４９７．２ʃ４９５．８ʃ７０．０００．２１５０．１３２ｎｄｎｄ湖水０．５０．７４５０．６５３０．５２３０．４９２１０６．０ʃ７１０４．２ʃ６１０４．６ʃ７９８．４ʃ４５４．９５４．９６４．７３４．８４９４．７ʃ６９６．６ʃ５９４．６ʃ７９６．８ʃ６㊀㊀注：ａ３次平行测定结果．ｂ３次测定相对标准偏差．ｃｎｄ未检出．图８㊀湖水样品中ＰＡＥｓ的色谱图．湖水样品（ａ），湖水加标０．５ｎｇ㊃ｍＬ－１（ｂ）和５ｎｇ㊃ｍＬ－１（ｃ）Ｆｉｇ．８㊀ＨＰＬＣ⁃ＵＶｃｈｒｏｍａｔｏｇｒａｍｓｏｆｌａｋｅｗａｔｅｒ（ａ），ａｎｄｉｔｓｓｐｉｋｅｄｓａｍｐｌｅｓｗｉｔｈ０．５ｎｇ㊃ｍＬ－１（ｂ）ａｎｄ５ｎｇ㊃ｍＬ－１（ｃ）ｏｆｅａｃｈａｎａｌｙｔｅ３㊀结论制备了超顺磁性的Ｆｅ３Ｏ４／Ｃ吸附剂，并用其从大体积环境水样中富集痕量的ＰＡＥｓ污染物．与传统的和文献报道的固相萃取方法比较，该方法具有如下优点：（ａ）超顺磁性吸附剂可以直接分散到水样中吸附目标物，达到吸附平衡后用磁铁分离洗脱，磁分离方法避免了耗时的过柱操作．（ｂ）Ｆｅ３Ｏ４／Ｃ具有纳米材料大的比表面积和碳材料强的吸附能力，因此从大体积水样中萃取目标物只需要少量吸附剂就能获得满意的结果．（ｃ）目标物的回收率不受溶液盐度和ｐＨ值的影响，因此在萃取时不需要对水样进行繁琐的调整．（ｄ）Ｆｅ３Ｏ４／Ｃ吸附剂的制备方法简单，所用试剂价格低廉，无毒．在进行萃取的过程中不会在环境水样中引入有毒有害的物质，环境友好．参㊀考㊀文㊀献［１］㊀王红芬，程晗煜，洪坚平．环境中酞酸酯的污染现状及防治措施［Ｊ］．环境科学与管理，２０１０，３５（７）：３３⁃３６［２］㊀ＣａｉＹＱ，ＣａｉＹＥ，ＳｈｉＹＬ，ｅｔａｌ．Ａｌｉｑｕｉｄ⁃ｌｉｑｕｉｄｅｘｔｒａｃｔｉｏｎｔｅｃｈｎｉｑｕｅｆｏｒｐｈｔｈａｌａｔｅｅｓｔｅｒｓｗｉｔｈｗａｔｅｒ⁃ｓｏｌｕｂｌｅｏｒｇａｎｉｃｓｏｌｖｅｎｔｓｂｙａｄｄｉｎｇｉｎｏｒｇａｎｉｃｓａｌｔｓ［Ｊ］．ＭｉｃｒｏｃｈｉｍｉｃａＡｃｔａ，２００７，１５７：７３⁃７９［３］㊀王超英，李碧芳，李攻科．固相微萃取／高效液相色谱联用分析水中邻苯二甲酸酯［Ｊ］．分析测试学报，２００５，２４（５）：３５⁃３８［４］㊀ＰｅñａｌｖｅｒＡ，ＰｏｃｕｒｌｌＥ，ＢｏｒｒｕｌｌＦ，ｅｔａｌ．Ｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｈｔｈａｌａｔｅｅｓｔｅｒｓｉｎｗａｔｅｒｓａｍｐｌｅｓｂｙｓｏｌｉｄ⁃ｐｈａｓｅｍｉｃｒｏｅｘｔｒａｃｔｉｏｎａｎｄｇａｓｃｈｒｏｍａｔｏｇｒａｐｈｙｗｉｔｈｍａｓｓｓｐｅｃｔｒｏｍｅｔｒｉｃｄｅｔｅｃｔｉｏｎ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０００，８７２：１９１⁃２０１［５］㊀李玫瑰，李元星，毛丽秋．微滴液相微萃取技术用于气相色谱⁃质谱法测定食品中的酞酸酯［Ｊ］．色谱，２００７，２５（１）：３５⁃３８［６］㊀王东新．中空纤维液相微萃取⁃气相色谱测定不同天然水体中的酞酸酯类化合物［Ｊ］．南京师范大学学报（工程技术版），２００８，８（３）：４３⁃４６［７］㊀胡庆兰．自制固相微萃取涂层同时测定水中的多环芳烃和酞酸酯［Ｊ］．吉林大学学报（理学版），２０１３，５１（２）：３１７⁃３２０［８］㊀王鑫，许小苗，俞晔，等．固相萃取⁃气相色谱法同时测定水中的酞酸酯类环境激素［Ｊ］．食品工业科技，２００８，２９（４）：２８７⁃２８９［９］㊀陈永山，骆永明，章海波，等．固相萃取法处理环境水样中酞酸酯：流速与除水方式的影响［Ｊ］．环境化学，２０１０，２９（５）：９５４⁃９５９［１０］㊀黄玉娟，陈永山，骆永明，等．气相色谱⁃质谱联用内标法测定土壤中１１种酞酸酯［Ｊ］．环境化学，２０１３，３２（４）：６５８⁃６６５㊀㊀１２期王颖辉等：碳包覆的磁性纳米材料萃取酞酸酯２２４９［１１］㊀ＣａｉＹＱ，ＪｉａｎｇＧＢ，ＬｉｕＪＦ，ｅｔａｌ．Ｍｕｌｔｉｗａｌｌｅｄｃａｒｂｏｎｎａｎｏｔｕｂｅｓａｓａｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎａｄｓｏｒｂｅｎｔｆｏｒｔｈｅｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｂｉｓｐｈｅｎｏｌＡ，４⁃ｎ⁃Ｎｏｎｙｌｐｈｅｎｏｌ，ａｎｄ４⁃ｔｅｒｔ⁃Ｏｃｔｙｌｐｈｅｎｏｌ［Ｊ］．ＡｎａｌＣｈｅｍ，２００３，７５：２５１７⁃２５２１［１２］㊀ＷａｎｇＨＹ，ＣａｍｐｉｇｌｉａＡＤ．Ｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓｉｎｄｒｉｎｋｉｎｇｗａｔｅｒｓａｍｐｌｅｓｂｙｓｏｌｉｄ⁃ｐｈａｓｅｎａｎｏｅｘｔｒａｃｔｉｏｎａｎｄｈｉｇｈ⁃ｐｅｒｆｏｒｍａｎｃｅｌｉｑｕｉｄｃｈｒｏｍａｔｏｇｒａｐｈｙ［Ｊ］．ＡｎａｌＣｈｅｍ，２００８，８０：８２０２⁃８２０９［１３］㊀ＺｈａｏＸＬ，ＳｈｉＹＬ，ＣａｉＹＱ，ｅｔａｌ．Ｃｅｔｙｌｔｒｉｍｅｔｈｙｌａｍｍｏｎｉｕｍｂｒｏｍｉｄｅ⁃ｃｏａｔｅｄｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓｆｏｒｔｈｅｐｒｅｃｏｎｃｅｎｔｒａｔｉｏｎｏｆｐｈｅｎｏｌｉｃｃｏｍｐｏｕｎｄｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＥｎｖｉｒｏｎＳｃｉＴｅｃｈｎｏｌ，２００８，４２：１２０１⁃１２０６［１４］㊀ＺｈａｏＸＬ，ＳｈｉＹＬ，ＷａｎｇＴ，ｅｔａｌ．Ｐｒｅｐａｒａｔｉｏｎｏｆｓｉｌｉｃａ⁃ｍａｇｎｅｔｉｔｅｎａｎｏｐａｒｔｉｃｌｅｍｉｘｅｄｈｅｍｉｍｉｃｅｌｌｅｓｏｒｂｅｎｔｓｆｏｒｅｘｔｒａｃｔｉｏｎｏｆｓｅｖｅｒａｌｔｙｐｉｃａｌｐｈｅｎｏｌｉｃｃｏｍｐｏｕｎｄｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２００８，１１８８：１４０⁃１４７［１５］㊀ＬｉＪＤ，ＺｈａｏＸＬ，ＳｈｉＹＬ，ｅｔａｌ．Ｍｉｘｅｄｈｅｍｉｍｉｃｅｌｌｅｓｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎｂａｓｅｄｏｎｃｅｔｙｌｔｒｉｍｅｔｈｙｌａｍｍｏｎｉｕｍｂｒｏｍｉｄｅ⁃ｃｏａｔｅｄｎａｎｏ⁃ｍａｇｎｅｔｓＦｅ３Ｏ４ｆｏｒｔｈｅｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｃｈｌｏｒｏｐｈｅｎｏｌｓｉｎｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓｃｏｕｐｌｅｄｗｉｔｈｌｉｑｕｉｄｃｈｒｏｍａｔｏｇｒａｐｈｙ／ｓｐｅｃｔｒｏｐｈｏｔｏｍｅｔｒｙｄｅｔｅｃｔｉｏｎ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２００８，１１８０：２４⁃３１［１６］㊀张小乐，王巍杰，张一江，等．磁性介孔硅胶萃取剂的制备及萃取性能研究［Ｊ］．环境化学，２０１２，３１（４）：４２２⁃４２８［１７］㊀ＺｈａｎｇＳＸ，ＮｉｕＨＹ，ＣａｉＹＱ，ｅｔａｌ．ＢａｒｉｕｍａｌｇｉｎａｔｅｃａｇｅｄＦｅ３Ｏ４＠Ｃ１８ｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓｆｏｒｔｈｅｐｒｅ⁃ｃｏｎｃｅｎｔｒａｔｉｏｎｏｆｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓａｎｄｐｈｔｈａｌａｔｅｅｓｔｅｒｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＡｎａｌＣｈｉｍＡｃｔａ，２０１０，６６５：１６７⁃１７５［１８］㊀ＺｈａｎｇＳＸ，ＮｉｕＨＹ，ＨｕＺＪ，ｅｔａｌ．ＰｒｅｐａｒａｔｉｏｎｏｆｃａｒｂｏｎｃｏａｔｅｄＦｅ３Ｏ４ｎａｎｏｐａｒｔｉｃｌｅｓａｎｄｔｈｅｉｒａｐｐｌｉｃａｔｉｏｎｆｏｒｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎｏｆｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０１０，１２１７：４７５７⁃４７６４［１９］㊀ＺｈａｎｇＳＸ，ＮｉｕＨＹ，ＺｈａｎｇＹＹ，ｅｔａｌ．Ｂｉｏｃｏｍｐａｔｉｂｌｅｐｈｏｓｐｈａｔｉｄｙｌｃｈｏｌｉｎｅｂｉｌａｙｅｒｃｏａｔｅｄｏｎｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓａｎｄｔｈｅｉｒａｐｐｌｉｃａｔｉｏｎｉｎｔｈｅｅｘｔｒａｃｔｉｏｎｏｆｓｅｖｅｒａｌｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒａｎｄｍｉｌｋｓａｍｐｌｅｓ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０１２，１２３８：３８⁃４５［２０］㊀ＢｒｕｃｅＩＪ，ＳｅｎＴ，Ｓｕｒｆａｃｅｍｏｄｉｆｉｃａｔｉｏｎｏｆｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｓｗｉｔｈａｌｋｏｘｙｓｉｌａｎｅｓａｎｄｔｈｅｉｒａｐｐｌｉｃａｔｉｏｎｉｎｍａｇｎｅｔｉｃｂｉｏｓｅｐａｒａｔｉｏｎｓ［Ｊ］．Ｌａｎｇｍｕｉｒ，２００５，２１：７０２９⁃７０３５［２１］㊀ＬｉＹ，ＬｅｎｇＴＨ，ＬｉｎＨＱ，ｅｔａｌ．ＰｒｅｐａｒａｔｉｏｎｏｆＦｅ３Ｏ４＠ＺｒＯ２ｃｏｒｅ⁃ｓｈｅｌｌｍｉｃｒｏｓｐｈｅｒｅｓａｓａｆｆｉｎｉｔｙｐｒｏｂｅｓｆｏｒｓｅｌｅｃｔｉｖｅｅｎｒｉｃｈｍｅｎｔａｎｄｄｉｒｅｃｔｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｈｏｓｐｈｏｐｅｐｔｉｄｅｓｕｓｉｎｇｍａｔｒｉｘ⁃ａｓｓｉｓｔｅｄｌａｓｅｒｄｅｓｏｒｐｔｉｏｎｉｏｎｉｚａｔｉｏｎｍａｓｓｓｐｅｃｔｒｏｍｅｔｒｙ［Ｊ］．ＪＰｒｏｔｅｏｍｅＲｅｓ，２００７，６：４４９８⁃４５１０［２２］㊀ＬｉＹ，ＸｕＸＱ，ＱｉＤＷ，ｅｔａｌ．ＮｏｖｅｌＦｅ３Ｏ４＠ＴｉＯ２ｃｏｒｅ⁃ｓｈｅｌｌｍｉｃｒｏｓｐｈｅｒｅｓｆｏｒｓｅｌｅｃｔｉｖｅｅｎｒｉｃｈｍｅｎｔｏｆｐｈｏｓｐｈｏｐｅｐｔｉｄｅｓｉｎｐｈｏｓｐｈｏｐｒｏｔｅｏｍｅａｎａｌｙｓｉｓ［Ｊ］．ＪＰｒｏｔｅｏｍｅＲｅｓ，２００８，７：２５２６⁃２５３８［２３］㊀ＬｉｍＳＦ，ＺｈｅｎｇＹＭ，ＺｏｕＳＷ，ｅｔａｌ．ＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆｃｏｐｐｅｒａｄｓｏｒｐｔｉｏｎｏｎｔｏａｎａｌｇｉｎａｔｅｅｎｃａｐｓｕｌａｔｅｄｍａｇｎｅｔｉｃｓｏｒｂｅｎｔｂｙａｃｏｍｂｉｎｅｄＦＴ⁃ＩＲ，ＸＰＳ，ａｎｄｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｉｎｇｓｔｕｄｙ［Ｊ］．ＥｎｖｉｒｏｎＳｃｉＴｅｃｈｎｏｌ，２００８，４２：２５５１⁃２５５６［２４］㊀ＰａｎＢ，ＸｉｎｇＢＳ．Ａｄｓｏｒｐｔｉｏｎｍｅｃｈａｎｉｓｍｓｏｆｏｒｇａｎｉｃｃｈｅｍｉｃａｌｓｏｎｃａｒｂｏｎｎａｎｏｔｕｂｅｓ［Ｊ］．ＥｎｖｉｒｏｎＳｃｉＴｅｃｈｎｏｌ，２００８．４２（２４）：９００５⁃９０１３［２５］㊀ＨｅｎｎｉｏｎＭＣ．Ｇｒａｐｈｉｔｉｚｅｄｃａｒｂｏｎｓｆｏｒｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎ［Ｊ］．ＪＣｈｒｏｍａｔｏｇｒＡ，２０００，８８５：７３⁃９５Ｃａｒｂｏｎｃｏａｔｅｄｍａｇｎｅｔｉｃｎａｎｏｐａｒｔｉｃｌｅｆｏｒｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎｏｆｐｈｔｈａｌａｔｅｅｓｔｅｒｓｆｒｏｍｗａｔｅｒｓａｍｐｌｅｓＷＡＮＧＹｉｎｇｈｕｉ１㊀㊀ＴＥＮＧＦｅｉ２㊀㊀ＺＨＡＮＧＹｕａｎｙｕａｎ３㊀㊀ＺＨＡＮＧＳｈｅｎｇｘｉａｏ３∗㊀㊀ＬＩＵＪｕｎｓｈｅｎ３㊀㊀ＷＵＱｉａｎ３（１．ＣｉｔｙＭａｎａｇｅｍｅｎｔＢｕｒｅａｕｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＰｒｏｔｅｃｔｉｏｎｏｆＹａｎｔａｉＤｅｖｅｌｏｐｍｅｎｔＺｏｎｅ，Ｙａｎｔａｉ，２６４００６，Ｃｈｉｎａ；２．ＳｈａｎｇｈａｉＧｅｎｅｒａｌＭｏｔｏｒ（Ｄｏｎｇｙｕｅ）ＡｕｔｏＣｏｍｐａｎｙ，Ｙａｎｔａｉ，２６４００６，Ｃｈｉｎａ；㊀３．ＬｕｄｏｎｇＵｎｉｖｅｒｓｉｔｙ，Ｙａｎｔａｉ，２６４０２５，Ｃｈｉｎａ）ＡＢＳＴＲＡＣＴＣａｒｂｏｎｃｏａｔｅｄＦｅ３Ｏ４ｎａｎｏｐａｒｔｉｃｌｅｓ（Ｆｅ３Ｏ４／Ｃ）ｗｅｒｅｓｙｎｔｈｅｓｉｚｅｄｂｙａｓｉｍｐｌｅｈｙｄｒｏｔｈｅｒｍａｌｒｅａｃｔｉｏｎａｎｄａｐｐｌｉｅｄａｓｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎ（ＳＰＥ）ｓｏｒｂｅｎｔｓｔｏｅｘｔｒａｃｔｔｒａｃｅｐｈｔｈａｌａｔｅｅｓｔｅｒｓ（ＰＡＥｓ）ｆｒｏｍｅｎｖｉｒｏｎｍｅｎｔａｌｗａｔｅｒｓａｍｐｌｅｓ．ＴｈｅＦｅ３Ｏ４／Ｃｓｏｒｂｅｎｔｓｐｏｓｓｅｓｓｈｉｇｈｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙｄｕｅｔｏｓｔｒｏｎｇａｄｓｏｒｐｔｉｏｎａｂｉｌｉｔｙｏｆｃａｒｂｏｎｍａｔｅｒｉａｌｓａｎｄｌａｒｇｅｓｐｅｃｉｆｉｃｓｕｒｆａｃｅａｒｅａｏｆｔｈｅｎａｎｏｐａｒｔｉｃｌｅｓ．Ｏｎｌｙ５０ｍｇｏｆｓｏｒｂｅｎｔｓｗｅｒｅｎｅｅｄｅｄｔｏｅｘｔｒａｃｔＰＡＥｓｆｒｏｍ５００ｍＬｗａｔｅｒｓａｍｐｌｅｓ．Ｔｈｅａｄｓｏｒｐｔｉｏｎｒｅａｃｈｅｄｅｑｕｉｌｉｂｒｉｕｍｒａｐｉｄｌｙａｎｄｔｈｅａｎａｌｙｔｅｓｗｅｒｅｅｌｕｔｅｄｗｉｔｈａｃｅｔｏｎｉｔｒｉｌｅｒｅａｄｉｌｙ．ＳａｌｉｎｉｔｙａｎｄｓｏｌｕｔｉｏｎｐＨｈａｄｎｏｏｂｖｉｏｕｓｅｆｆｅｃｔｏｎｔｈｅｒｅｃｏｖｅｙｏｆＰＡＨｓ，ｗｈｉｃｈａｖｏｉｄｓｆｕｓｓｙａｄｊｕｓｔｍｅｎｔｔｏｗａｔｅｒｓａｍｐｌｅｂｅｆｏｒｅｅｘｔｒａｃｔｉｏｎ．Ｕｎｄｅｒｏｐｔｉｍｉｚｅｄｃｏｎｄｉｔｉｏｎｓ，ｔｈｅｄｅｔｅｃｔｉｏｎｌｉｍｉｔｏｆＰＡＥｓｗａｓｉｎｔｈｅｒａｎｇｅｏｆ１７５８ｎｇ㊃Ｌ－１．Ｔｈｅａｃｃｕｒａｃｙｏｆｔｈｅｍｅｔｈｏｄｗａｓｅｖａｌｕａｔｅｄｂｙｔｈｅｒｅｃｏｖｅｒｉｅｓｏｆｓｐｉｋｅｄｓａｍｐｌｅｓ．Ｇｏｏｄｒｅｃｏｖｅｒｉｅｓ（９４．６％１０６．６％）ｗｉｔｈｌｏｗｒｅｌａｔｉｖｅｓｔａｎｄａｒｄｄｅｖｉａｔｉｏｎｓｆｒｏｍ２％ｔｏ８％ｗｅｒｅａｃｈｉｅｖｅｄ．ＴｈｉｓｎｅｗＳＰＥｍｅｔｈｏｄｐｒｏｖｉｄｅｓｓｅｖｅｒａｌａｄｖａｎｔａｇｅｓ，ｓｕｃｈａｓｈｉｇｈｅｘｔｒａｃｔｉｏｎｅｆｆｉｃｉｅｎｃｙ，ｈｉｇｈｂｒｅａｋｔｈｒｏｕｇｈｖｏｌｕｍｅ，ｃｏｎｖｅｎｉｅｎｔｅｘｔｒａｃｔｉｏｎｐｒｏｃｅｄｕｒｅ，ａｎｄｓｈｏｒｔａｎａｌｙｓｉｓｔｉｍｅ．Ｋｅｙｗｏｒｄｓ：ＰＡＥｓ，ｍａｇｎｅｔｉｃｓｏｌｉｄ⁃ｐｈａｓｅｅｘｔｒａｃｔｉｏｎ，ｃａｒｂｏｎｍａｔｅｒｉａｌｓ．。

电磁场与电磁波(英文版)ppt课件

1831年英国科学家法拉第（1791－1867）发现电磁感应现象，创建了电磁感应定律，说明时变磁场可以产生时变电场。
10
A Great Innovation 重大突破
In 1873, British scientist James Clerk Maxwell (1831—1879) postulated the displacement current, which provided the link between a time-varying electric field and a magnetic field. He put on a firm mathematical foundation the laws governing an electromagnetic field. They are known today as the famous Maxwell’s equations. 1873年英国科学家麦克斯韦（1831－1879）提出了位移电流的假设，认为时变电场可以产生时变磁场，并以严格数学方程描述了电磁场与波应该遵循的统一规律，这就是著名的麦克斯韦方程。
Vector analysis 4
EM induction 3
Electrostatic fields 7
Time-varying EM fields 7
Boundary-value problems 4 Plane EM waves 10
Steady current fields 3
Guided EM waves 8
In 1785, French scientist Charles Augustin de Coulomb (1736—1806) discovered Coulomb’s law (1785年法国科学家库仑（1736－1806）通过实验创建了著名的库仑定律), and it gives the relationship between the force experienced by two small charged objects and the distance between them.

磁加载混凝工艺参数优化试验研究

2020年26期工艺创新科技创新与应用Technology Innovation and Application磁加载混凝工艺参数优化试验研究黄嘉诚1，方茜1，隋军2（1.广州大学土木工程学院市政工程系，广东广州510006；2.广东首汇蓝天工程科技有限公司，广东广州510060）引言随着我国经济水平的高速发展，居民的生活用水量也随之增长，而生活污水的排放种类和数量也随之增加。

在我国经济发展较为落后的城市或地区，由于污水处理系统与市政管网配套系统建设的滞后或污水处理设施运行的不完善，而在城市的排口处又暂时不具备截污纳管的条件，而造成了生活污水直排进水体的现象。

因此，必须采取某些应急处理措施来对这部分生活污水进行处理，但考虑到排口处生活污水排水量不连续，且处理空间有限，传统的污水处理工艺很难施展[1]。

在这种情况下，通过磁混凝技术，在短期内对市政生活污水进行应急处理具有重要的现实意义。

常规的混凝技术，通过简单的混凝+絮凝的化学沉淀法对生活污水进行处理，不仅处理效果一般无法满足排放要求，出水水质也极不稳定。

且常规混凝沉淀一体化设备的沉淀池占地面积大、重量重、运输难也进一步制约了该技术在实际中的应用[2]。

磁混凝技术是在常规混凝技术只投加混凝剂、絮凝剂的基础上，在水中投加磁种，从而形成一种新的“磁絮体”，由于磁粉颗粒密度极大，能有效地加速磁絮体的沉降，提升了磁絮体的沉降能力，相比常规混凝沉淀，能进一步减少沉淀池占地面积[3]。

综上所述，磁混凝技术具有处理效率高、出水水质稳定、减少占地面积、节约成本等优势，在市政污水的应急处理领域拥有光明的前景。

本研究以考察磁混凝技术在市政污水应急处理过程中的可行性进行研究，以某市污水应急处理站进水口原水作为研究对象，通过烧杯试验，考察混凝剂、絮凝剂和磁粉的投加量以及磁粉粒径与投加顺序对原水中各类指标去除率的影响，找出最佳参数，为磁混凝污水处理工艺在实际中的运行提供理论指导。

法拉第电磁感应定律英文解释

法拉第电磁感应定律英文解释Faraday's Law of Electromagnetic InductionElectromagnetic induction is a fundamental concept in the field of electromagnetism that describes the relationship between a changing magnetic field and the generation of an electric current or voltage. This phenomenon was first discovered and formulated by the English scientist Michael Faraday in the 1830s and is known as Faraday's law of electromagnetic inductionFaraday's law states that a changing magnetic field induces an electromotive force (EMF) or voltage in a conducting loop or circuit The magnitude of the induced EMF is proportional to the rate of change of the magnetic flux through the loop or circuit According to Faraday's law the induced EMF is equal to the negative of the time rate of change of the magnetic flux through the loop or circuitThe mathematical expression of Faraday's law is given by the equationε = -dΦ/dtwhere ε is the induced EMF Φ is the magnetic flux and t is time The negative sign in the equation indicates that the induced EMF opposes the change in the magnetic flux according to Lenz's law which states that the direction of the induced current is such that it opposes the change in the magnetic field that caused itThe magnetic flux Φ is defined as the product of the magnetic field B and the area A of the loop or circuit through which the field passes Mathematically this can be expressed asΦ = B·ASubstituting this expression for the magnetic flux into Faraday's law equation we getε = -d(B·A)/dtThis equation can be further expanded to show the relationship between the induced EMF the rate of change of the magnetic field and the area of the loop or circuitε = -A·dB/dt - B·dA/dtThe first term on the right-hand side of this equation represents the EMF induced due to the changing magnetic field while the secondterm represents the EMF induced due to the changing area of the loop or circuitFaraday's law of electromagnetic induction has numerous practical applications in various fields of science and technology Some of the important applications include1 Electric generators and transformers Electric generators convert mechanical energy into electrical energy by exploiting the principle of electromagnetic induction Transformers on the other hand use electromagnetic induction to change the voltage level of an alternating current AC signal2 Electric motors Electric motors convert electrical energy into mechanical energy by using the force generated by the interaction between a magnetic field and an electric current3 Eddy current brakes Eddy currents induced in a conducting material by a changing magnetic field can be used to create braking forces to slow down or stop the motion of a moving object4 Induction heating Electromagnetic induction is used in induction heating to heat electrically conducting materials by inducing eddy currents within them5 Magnetic resonance imaging MRI Faraday's law of induction is a fundamental principle underlying the operation of MRI machines which use rapidly changing magnetic fields to generate images of the human body6 Electromagnetic damping and vibration control Electromagnetic induction can be used to create damping forces that can be utilized to control the vibrations of mechanical systemsFaraday's law of electromagnetic induction is a fundamental principle in electromagnetism that describes the relationship between a changing magnetic field and the generation of an electric current or voltage This principle has numerous practical applications in various fields of science and technology and continues to be an important area of study and research in the field of physics。

英语介绍自己的厨房作文

英语介绍自己的厨房作文My kitchen is the heart of my home where I spend a significant amount of time each day preparing meals for myself and my family. It is a well-designed and functional space that allows me to efficiently cook and entertain. The kitchen is outfitted with modern appliances and ample counter space, making it a comfortable and enjoyable place to work.The first thing you notice when you enter my kitchen is the large, stainless steel refrigerator that dominates one wall. It is a side-by-side model with a water and ice dispenser in the door, which is incredibly convenient. The refrigerator is always well-stocked with fresh ingredients, condiments, and leftovers from previous meals. I try to keep the shelves organized, with similar items grouped together for easy access.Next to the refrigerator is my gas stove and oven combo. I absolutely love cooking with gas as it provides precise temperature control and heats up quickly. The stove has five burners of varying sizes, allowing me to accommodate pots and pans of different dimensions. Theoven is spacious and evenly heats, making it perfect for baking everything from cookies to casseroles. I keep a selection of baking sheets, roasting pans, and other essential cooking tools nearby for easy access.On the opposite wall, I have a large farmhouse-style sink with a high-arc faucet. This sink is deep enough to easily accommodate large pots and pans, and the faucet provides excellent water pressure for quickly filling vessels or rinsing produce. Adjacent to the sink is my dishwasher, which is a real time-saver after meal preparation and clean-up. I try to run the dishwasher after each major meal to keep the sink clear and the kitchen tidy.My kitchen also features abundant counter space, which I find invaluable. I have a long stretch of solid quartz countertops that provide ample room for meal prep, baking, and even casual dining. The countertops are durable and easy to clean, which is important given the amount of cooking I do. Underneath the counters, I have a combination of drawers and cabinets for storage. The drawers hold my cooking utensils, gadgets, and smaller items, while the cabinets house my pots, pans, bakeware, and pantry staples.In the center of the kitchen is a large island that serves multiple purposes. It provides additional counter space for food preparation, as well as seating for casual meals and socializing. The island haselectrical outlets built into the side, allowing me to plug in small appliances like a blender or stand mixer right where I need them. Overhead, I have pendant lights that cast a warm glow over the island, creating an inviting atmosphere.One of my favorite features of the kitchen is the large window that spans the entire back wall. It floods the space with natural light and offers a lovely view of my backyard garden. I love standing at the sink and gazing outside while washing dishes or looking out for birds and butterflies. The window also makes the kitchen feel more open and airy.To complement the abundant natural light, I have installed a combination of recessed lighting and under-cabinet lighting. The recessed lights provide overall illumination, while the under-cabinet lights highlight the countertops and make meal preparation easier. I can control the lighting with dimmers, allowing me to set the mood for different occasions, whether I'm cooking a quick weeknight dinner or hosting a dinner party.In terms of decor, I have chosen a neutral color palette of whites, grays, and natural wood tones. This creates a clean and timeless aesthetic that I find very pleasing. I have open shelving on one wall where I display some of my favorite ceramic dishware and cooking books. On the opposite wall, I have a large chalkboard where I canwrite out grocery lists, menu plans, or inspirational quotes.Throughout the kitchen, I have incorporated various storage solutions to keep things organized. In addition to the cabinets and drawers, I have a pull-out pantry that houses my dry goods, spices, and baking supplies. I also have a built-in wine rack that holds a small but carefully curated selection of wines. These organizational elements help me maintain a tidy and efficient workspace.One of the most important aspects of my kitchen is the high-quality appliances I have chosen. In addition to the reliable refrigerator and stove, I have a powerful range hood that effectively removes steam and odors while I'm cooking. I also have a sleek, stainless steel dishwasher that cleans dishes thoroughly and quietly. These appliances not only look great but also perform exceptionally well, making meal preparation and clean-up a breeze.Finally, I have added some personal touches to the kitchen to make it feel warm and inviting. I have a small table in the corner where I enjoy my morning coffee and read the newspaper. On the windowsill, I have a collection of potted herbs that I use in my cooking. I also have a magnetic board where I display photos of my family and friends, as well as any artwork or notes my children have created.Overall, my kitchen is a space that I truly enjoy spending time in. It iswell-designed, functional, and reflective of my personal style. Whether I'm whipping up a quick weeknight meal or hosting a dinner party, I find great satisfaction in working in this comfortable and efficient space. It is the heart of my home, and I take great pride in maintaining it as a welcoming and inspiring place for myself and my loved ones.。

矿物加工专业英语

12) paramagnetic substance — n. some substances which can appeal the effect from magnetic field〖顺磁性物质，顺磁质〗
13) rutile — n. a mineral with chemical formula TiO2 〖金红石〗 14) monasite — n. a mineral with chemical formula (Ce,La)PO4, consists of Rare Earth(RE)〖独居石〗
矿物加工专业英语
Teaching Plan on Specialized English Course for Mineral Processing Technology
Part 1 Magnetic and High-tension Separation Part 2 Types of Magnetic Separator Part 3 High-intensity Separators Part 4 High-intensity Separators Types Part 5 Magnetic Intensities Required to Extract Minerals Part 6 Super-conducting Separators Part 7 High-intension Separation Part 8 Typical Behavior of Minerals in High-tension Separators Part 9 Operating Principle of High-tension Separator Part 10 Froth Flotation
18) ferromagnetic substance — n. some substances which have susceptibility to magnetic forces and retain some magnetism when removed from the field 〖铁磁性物质，铁磁质〗

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