Electromagnetic Form Factors of the SU(3) Octet Baryons in the semibosonized SU(3) Nambu-Jo

光的衍射英文作文Light DiffractionLight is a fundamental aspect of our physical world, and its behavior has been the subject of intense study and fascination for centuries. One of the most intriguing and complex phenomena associated with light is diffraction, which refers to the bending and spreading of light waves as they encounter obstacles or apertures. This phenomenon has profound implications in various fields, from optics and quantum mechanics to biology and technology.At its core, diffraction is a wave-like property of light, where the interaction between light and the physical structures it encounters leads to the interference and redistribution of the light waves. This process is governed by the principles of wave interference, where the constructive and destructive interference of light waves result in patterns of light and dark regions, known as diffraction patterns.The fundamental principles of diffraction can be understood by considering the wave nature of light. Light, like other forms of electromagnetic radiation, can be described as a wave, with a specific wavelength and frequency. When light encounters an obstacle or anaperture, the waves are forced to bend and spread out, creating a diffraction pattern. The specific characteristics of this pattern are determined by factors such as the size and shape of the obstacle or aperture, as well as the wavelength of the light.One of the most well-known examples of diffraction is the phenomenon of single-slit diffraction. When light passes through a narrow slit, the resulting diffraction pattern consists of a central bright region, known as the central maximum, surrounded by alternating bright and dark regions, known as diffraction fringes. The spacing and intensity of these fringes are directly related to the wavelength of the light and the width of the slit.Another important aspect of diffraction is the concept of the Fraunhofer diffraction, which describes the diffraction pattern observed at large distances from the aperture or obstacle. In this case, the diffraction pattern is characterized by a series of bright and dark spots, known as the Fraunhofer diffraction pattern. This pattern is particularly useful in applications such as optical imaging, spectroscopy, and the design of diffraction-based optical devices.Diffraction also plays a crucial role in the behavior of light in various natural and man-made systems. For example, the diffraction of light through small apertures or slits is responsible for the characteristic patterns observed in the interference of light, such as those seen inYoung's double-slit experiment. Additionally, the diffraction of light around the edges of objects or through small openings is responsible for the phenomena of diffraction fringes, which can be observed in various optical devices and natural phenomena, such as the colorful patterns seen in the wings of some insects or the halos and glories observed around the Sun or Moon.The study of diffraction has also led to the development of numerous applications in science and technology. In optics, diffraction is used in the design of various optical devices, such as diffraction gratings, which are used in spectroscopy and other analytical techniques. In the field of quantum mechanics, the wave-like nature of particles, as described by the de Broglie hypothesis, has led to the observation of diffraction patterns in the behavior of subatomic particles, such as electrons and neutrons.Furthermore, the understanding of diffraction has been instrumental in the development of modern imaging techniques, such as X-ray crystallography, where the diffraction of X-rays by the atoms in a crystal is used to determine the arrangement and structure of the atoms within the crystal. Similarly, the diffraction of light by various biological structures, such as the compound eyes of insects or the structures found in the wings of some butterflies, has inspired the development of biomimetic materials and devices.In conclusion, the phenomenon of light diffraction is a fundamental and fascinating aspect of our physical world. It is a testament to the wave-like nature of light and the complex interplay between light and the physical structures it encounters. The study of diffraction has led to numerous insights and advancements in various fields, and its continued exploration promises to yield further discoveries and innovations that will shape our understanding of the universe and the technology we use to interact with it.。

ElectromagneticsRichard H.Selfridge,David V.Arnold,and Karl F.Warnick Department of Electrical and Computer Engineering459Clyde BuildingBrigham Young UniversityProvo,UT84602July30,2001We would appreciate your suggestions and corrections to this draft.Send email to warnick@. Website:/ee/forms/(c)1999Chapter1ELECTROSTATICS1.1Introduction1.1.1OverviewMany applications of electrical engineering require a knowledge of the behavior of voltages and currents in electronic devices and within conductors.In many other situations it is not enough to understand the behavior the voltages and currents in just the conductors and other components,but also the influence of the voltage and current on surrounding materials.In physics classes we learn that electric and magneticfields extend beyond the electrical carriers within a device.In electrical and computer engineering the extension of thefields beyond electronic devices and wires can have both beneficial and deleterious effects.Withoutfields we would not have such modern conveniences as cellFigure1.1:Crosstalk between two telephone transmission lines.phones,television,or even the simplest computer memory chip.On the other hand,unwantedfield interactions can cause reversible and irreversible degradation in almost all types of electrical engineering systems.A common example of this type of degradation is evident when a telephone signal on one line leaks over to an adjacent line.This annoying phenomenon is known as cross talk.The diagram in Fig.1.1shows that thefield from one line extends into the other.In this chapter we examine some of the behavior of electricfields and electricflux.We use theflat panel display as a motivating example for this study.We have chosen theflat panel display as an illustrative example because it shows the ubiquitous nature of electromagnetics in current technology.Flat panel displays are expected to be the video display technology of the future for replacing the current bulky screens on laptop,television,and other applications.The most commonflat panel displays are based on liquid crystal display(LCD)technology.Fig.1.2shows a representative cell of aflat panel LCD.Each cell or pixel has a liquid crystal material sandwiched between two transparent conducting plates as shown in Fig.1.2.The LCD either passes light or blocks light depending on the voltage difference between the two plates.The difference in voltage affects the liquid crystal material by means of the electricfield generated between the two plates.Each of the liquid crystal cells represents one of the more than 50,000individual picture elements or pixels on the screen.Each cell is similar to the parallel plate capacitor studied in fundamental physics courses.The parallel plate structure is used throughout this section as a basis for our description of electricfields and electricfluxes.34CHAPTER1.ELECTROSTATICSCel lFigure1.2:A cell in aflat panel LCD display.Traditionally electrical engineers describe electricfields in terms of vectors.Although vector descriptions of electromagnetic principles are valuable because most engineering students are already familiar with them and because they provide insights into some of the physical properties offields,vector descriptions offields are somewhat limited in presenting a complete visual description offields.This chapter introduces differential forms as a powerful tool for describing and analyzing electricfields.Given that this is likely the reader’sfirst exposure to differential forms,the principles of differential forms are discussed in detail as they are introduced.For both comparison and completeness electromagneticfields are represented in terms of vectors also.We introduce differential forms because they provide a powerful and concise mathematical framework for electro-magnetics.Differential forms make a clear distinction between electricflux and electricfield.They make it simpler to derive theorems and to make coordinate transformations in electromagnetics.However,probably the most important advantage of differential forms at the undergraduate level is that they offer a unique and clear geometric description of electromagnetics not possible using vectors alone.The visual representations that accompany forms are likely to re-main in the minds of students whether or not they go on to specialize in electromagnetics or one of its sub-disciplines. These advantages make the additional effort in learning forms worthwhile.Also,students usuallyfind it fun to learn differential forms because forms are elegant and simple to manipulate.1.1.2Parallel conducting platesIn this section we focus our attention on the electricfields associated with parallel conducting plates.In the other chapters we shall see that parallel plate transmission lines are often used to describe a variety of important waveguide types.Figure1.3shows a general description of parallel conducting plates,the parallel plate capacitor.VFigure1.3:A parallel plate capacitorIn this representation we usually consider the separation distance of the plates to be less than one-tenth the length of the conductors.This means that thefields between the plates will not be very different from how they would appear if the plates were infinite in extent.We assume that a potential of5volts is applied to the top conducting plate,that the1.1.INTRODUCTION5Figure1.4:The potential between plates of a parallel plate capacitorlower plate is grounded and that the two plates are separated by1mm.For now we assume the material between the two plates is uniform.We notice that the voltage(electric potential)changes with position from the top to the bottom plate.Ourfirst important question is:“What is the potential distribution between the two plates?”It is reasonable to assume that the potential varies from5volts at the top plate to0volts at the bottom plate in a linear fashion because the material between the plates is the same throughout.We can think of planes of constant voltage between the plates as shown in Fig.1.4.These planes represent the change in potential from the top plate to the bottom plate.If one follows a path from the top plate to the bottom plate,counting the planes crossed along the way,the number of planes pierced by the path is proportional to the voltage difference between the two conducting plates.The constant of proportionality is the electricfield strength in volts per plane.We can express this sum in terms of an integral astopbottomThe quantity under the integral sign is a differential form.It is called a1-form because it has a single variableof integration.The differential form is called the electricfield1-form.In this expression,is a measure of howmuch the potential changes per unit distance and has units of V/m.In this case V/m.The planes inFig.1.4are a convenient geometrical representation of the electricfield1-form.The spacing of the planes indicates the strength of thefield;the higher thefield the more closely spaced the planes.In three dimensional space four degrees of forms exist,0,1,2,and3-forms.Each of these forms has several important examples in electromagnetics.These forms are used and explained in detail as needed in later sections and chapters.For the parallel plate configuration the electricfield only has surfaces perpendicular to the direction.Similarly,the1-form surfaces could be perpendicular to the-axis or-axis and would then be written in terms of dyor dz,respectively.In the general case a1-form is a linear combination of these differentials,so the surfaces may be skew to the coordinate axes and curved as shown in Fig.1.5.In the differential forms model of parallel conducting plates,not only does a voltage exist on the plates,but an electricfield,represented by forms,exists between the plates.This is the equipotential representation of thefield,or the energy picture.Understanding offields is also enhanced if one looks at the electricfield between the plates from the point of view of what happens to small charged body placed in between the two plates.Consider the potential difference created between the parallel plates as connected to the voltage source.The voltage source draws electrons away from the top conducting plate leaving excess positive charges on its surface. Likewise the bottom conducting plate has negative charges on its surface.A positive test charge placed between the plates is attracted to the negative plate as shown in Fig.1.6.This force of attraction is proportional to the strength of the electricfield between the plates,is in the direction of the electricfield,and is known as the Lorentz force.When using the force picture of electricfields it is usually most convenient to use vectors in place of forms.The electricfield vector is shown in thefigure.Its length represents the strength of the electricfield and its direction is indicated by the ing vector notation the Lorentz force law is expressed as(Lorentz force law,no magneticfields)where is the charge,is the force vector,and is the electricfield vector.6CHAPTER1.ELECTROSTATICSyzxFigure1.5:A general1-form with surfaces that curve in space.-VFigure1.6:A test charge experiences a force due to an electricfield.Electric charge plays an important role in the description offields using differential forms.From physics we know that with every positive charge there is an associated negative charge.We can view this association as a tube that links or connects a positive charge to a negative charge through intervening material.For the parallel plate example these tubes are shown connecting positive charges on the top plate to negativecharges on the bottom plate.ThetubesshowninFig.1.7are the geometrical representation of a2-form.The2-forms shown can be expressed as.This is a2-form because it has two differential elements.Notice that each tube contains a specified amount of charge.The charge that exists on the plates of the capacitor can be found by counting theflux tubes joining the top and bottom plates.Mathematicallythiscounting is equivalenttointegratingthe2-formtubesover the surface area between the plates ofthecapacitor:areaInthis representation we see that is the charge per tube,so that represents the concentration of charge per unit area.From the discussion ofthe graphical representation of1-forms it isapparent that the2-form is composed of a 1-form perpendicular to the-direction and another perpendicular to the–direction.The connection between charges represented by tubes is called the electricflux density.Flux meansflow,and although no physical particlesflow from one plate to the other we can think of a stream of influenceflowing from one plate to the other as one charge connects through space to its equal and opposite counterpart.The coefficients of a2-form give the spacing of the tubes,the larger the coefficients are,the more densely packed the tubes become.An arbitrary2-form has coefficients that are functions of position and the associated tubes may curve and diverge and converge at various points in space.From the example of the parallel conducting plates it is clear that there is a physical connection between the1.1.INTRODUCTION 7Figure 1.7:Tubes of flux in a parallel plate capacitorelectric field and the electric flux density.We can make geometric and algebraic connections between field and flux using differential forms.Examination of the geometry of electric fields and fluxes shows that the 1-form planesare composed of the planes that are mutually perpendicular to both of the planes that comprise the 2-form tubes asshown in Fig.1.7.In terms of the algebra of forms we require an operator that creates a 1-form from a 2-form and vice versa.This operator is discussed in Sec.1.5.Figure 1.8:Energy density boxes formed by intersection of electric field intensity surfaces and flux density tubes.To now,we have shown that the electric field may be represent as 1-form planes and that the flux is represented by 2-form tubes.Now let us see what if anything can be made of the boxes formed by combining the field planes and the flux tubes as shown in Fig.1.8.To find out what those boxes represent we express the combination algebraically asvolThe combination of the 1-form electric field and the 2-form magnetic flux creates an 3-form entity under the integral sign.Multiplying the dimensional units of and givesCm V m J mHence the volume integral of the field multiplied by the flux is the total energy stored in a region of space by the fields present in the region.The 3-form quantity under the integral sign is the energy contained in a cube.This description of energy density helps us understand why the refresh rate on a flat panel display is limited.Recall that the individual picture elements (pixels)of a flat panel display are illuminated or not depending on the voltage that is applied to them.To switch from one view to another requires that the pixels be changed about 30times8CHAPTER 1.ELECTROSTATICS each second to prevent the eye from seeing a flicker.This means that time is required to move energy to and from the region between the plates to switch from the off state to the on state and any energy stored between the plates must be removed during the process of switching from the on state to the off state.Energy transfer in time is de fined as power.Therefore,switching states in a finite amount of time requires power and takes time.In another view of this we can consider the capacitance of the system and calculate the time required to change states by using the RC time constant of the circuit.It is interesting to note that we can calculate the capacitance from the electric field and the electric flux.The fundamental de finition of capacitance is the amount of charge stored given a separation voltage.The capacitance of a single cube de fined by the intersection of the tubes of with the planes ofis simply the quotient,C/V or Farads.The examples given in this section have introduced physical descriptions of both electric field and electric flux.Although these examples are simple they present a useful foundation upon which systems with greater mathematical and physical complexity can be built.The following sections of this chapter show how to use these concepts in a more general setting.1.21-formsThe graphical representations described in the introduction are useful in gaining intuitive understanding of the behavior of electromagnetic fields.In order to work analytically with the laws which govern the fields,we must develop a mathematical structure to accompany the graphical representations of the previous section.As we saw in the previous section,electric field intensity represents potential change with distance.In order to find the total potential difference between two points,we need to integrate the electric field along a path between the points.Graphically,this means that we count electric field intensity surfaces.Mathematically,we must perform a path integral.Quantities which are integrated over paths are called 1-forms.In the introduction,we discussed the example of a 1-form which represented variation of a field in the –direction.In general,a 1-form can represent variation in any direction,and can be a combination of differentials of all of the coordinates.An arbitrary 1-form can be written(1.1)The three quantities ,,and are the components of the 1-form.Two 1-forms and can be added,so that(1.2)1-forms can be integrated over paths.As shown in the introduction,we graphically represent a 1-form as surfaces.The 1-form has surfaces perpendicular to the –axis spaced a unit distance apart.These surfaces are in finite in theand directions.The integral of over a path from the point to isThis matches the graphical representation in Fig.1.9a,since the path shown in the figure crosses four surfaces.If the path were not of integer length,we would have to imagine fractional surfaces in between the unit spaced surfaces.A path from to ,for example,crosses surfaces.We can also think of as a 1-form in the plane.In this case,the picture becomes a series of lines perpendicularto the –axis spaced a unit distance apart,as shown in Fig.1.9b.Graphically,integrals in the plane are similar tointegrals in three dimensions:the value of a path integral is the number of lines pierced by the path.In order to graphically integrate a 1-form properly,we also have to think of the surfaces as having an orientation.The integral of the 1-form over a path from to is .Thus,when we count surfaces piercedby a path,we have to compare the sign of the 1-form with the direction of the path in order to determine whether the surface contributes positively or negatively.The orientation of surfaces can be indicated using an arrowhead on each surface,but since the orientation is usually clear from context,to reduce clutter we do not indicate it in figures.A more complicated 1-form,such as ,has surfaces that are oblique to the coordinate axes.This 1-formis shown in Fig.1.10.The greater the magnitude of the components of a 1-form,the closer the surfaces are spaced.For 1-forms with components that are not constant,these surfaces can be curved,as shown in Fig.1.5.The surfaces can also originate along a line or curve and extend away to in finity,or the surfaces may be finite.In this case,the1.2.1-FORMS9xy(a)(b)yxFigure1.9:(a)The1-form integrated overa path from the pointto.(b)The1-form in the plane.yxFigure1.10:The1-form.integral over a path is still the number of surfaces or fractional surfaces pierced by the path.Some1-forms are too complicated to be drawn as surfaces in three dimensions(we will give a condition for this later),but any1-form can be drawn in the plane.A1-form represents a quantity which is integrated over a path.A vector represents a quantity with a magnitude and direction,such as displacement or velocity.Despite this difference,both types of quantities have three independent components,and can be used interchangeably in describing electromagneticfield quantities.Mathematically,vectors and differential forms are closely related.In euclidean coordinates,wecan makeacorrespondence betweenvectorsand forms.The1-formandthevector areequivalentifthey have thesamecomponents:(1.3) We say that the1-form and the vector are dual.Since it is easy to convert between the differential form and vector representations,one can choose the quantity which best suits a particular problem.We will see in the next section that in coordinate systems other then euclidean,the duality relationship between forms and vectors changes.1.2.1Curvilinear CoordinatesMany electromagnetics problems have some type of inherent symmetry.In solving problems,it isconvenient tochoose acoordinatesystem whichreflects that symmetry.Forexample,the equation which defines acylinder in rectangularcoordinates,,becomes in the cylindrical coordinate system,where is the radial distance from the–axis.10CHAPTER 1.ELECTROSTATICS In general,in three dimensions a coordinate system consists of threefunctions,,and which assign numbers to each point of space.For convenience,we assume that the directions in which each of the coordinates is changing are perpendicular,so that the coordinate system is orthonormal.In such a coordinate system,the unit differentials are writtenas,,and .The the threefunctions,,and are such that the integral over any one of the unit differentials over a path of unit euclidean length in the direction of the particular coordinate is equal to one.For example,if the length of the pathfromto has unit length,thenThese unit differentials correspond to basis vectors according to therelationshipsIn this section,we give thefunctions,,and for two of the most common curvilinear coordinate systems.yzxFigure 1.11:The surfaces of unit differentials in general orthonormal curvilinear coordinates are always a unit distance apart.Cylindrical CoordinatesIn the cylindrical coordinate system,a point in space is speci fied by theradial distanceofitscoordinates,anglefromthe axisin the–plane ,and height in the direction (Fig.1.12).Thus,a point iswritten(1.4)in cylindrical coordinates.The differentials of thecylindricalcoordinate systemare,and .To convert forms into unit vectors,the angular differential must be made intoaunit differential .1-forms correspond tovectorsby therulesFigure 1.13shows the pictures of the differentials of the cylindrical coordinate system.The 2-forms can be obtained by superimposingthesesurfaces.Tubesof ,for example,are square donut–shaped andpoint in the direction.Spherical CoordinatesIn the spherical coordinate system,a point in space is speci fied by the radialdistancefromtheorigin,angle from theaxis inthe–plane ,andangle fromthe axis ,as shown in Fig.1.15.A point iswritten(1.5)1.2.1-FORMS11Figure 1.12:The cylindrical coordinate system.(a)z yx (c)(b)zyx xyz Figure1.13:Surfacesof,scaled byand.inthese coordinates.Thedifferentials ofthe spherical coordinate system are,and .To convertformsintounit vectors,theangular differentials mustbe madeinto unit differentialsand.1-formscorrespondto vectorsbytherules Fig.1.16shows the pictures of the differentials of the spherical coordinate system.1.2.2Integrating 1-forms over pathsThe laws of electromagnetics are expressed in terms of integrals of fields represented by differential forms.In order to apply the laws of electromagnetics,we must therefore be able to compute the values of integrals of differential forms.Since 1-forms are by de finition mathematical quantities which are integrated over paths,the process of evaluating an integral of a 1-formis very natural.The key ideaisthat wecan replacethe coordinates ,,and (or ,,in curvilinear coordinates),with an equation for a path in terms of a parameter.The parameter of a path is often denoted by .12CHAPTER 1.ELECTROSTATICSFigure 1.14:Unit differentials in cylindrical coordinates represented as faces of a differential volume.Figure 1.15:The spherical coordinate system.In general,a path is written in the form (f(t),g(t),h(t)),so that thefunctions,,and give the coordinates of a point on the path for each value of .We replace the coordinates in a 1-form by these functions,and then the integral can be evaluated.For a differential,when the coordinate is replaced by a function de fining the path,we then take the derivative by to produce a new differential in the variable .Forexample,becomes ,where the prime denotes the derivative of thefunction by (this operation is a special case of the exterior derivative ,which will be discussed in a later chapter).The differential form now has a singledifferential,,and the integral can be performed using standard rules of calculus.Example 1.1.Integrating a 1-form over a path in rectangular coordinatesConsider the1-formand apath which lies along thecurve from thepointto .We wish to find (1.6)We parameterize the path in the variable ,so that the pathbecomes ,withranging from zero to one.We then substitute these valuesforand into theintegral,1.2.1-FORMS13yzx(a)(b)zyx(c)yxzFigure1.16:Surfacesof,scaled by and scaledby.Figure1.17:Unitdifferentialsin sphericalcoordinates represented as faces of adifferentialvolume.Example1.2.Integrating a1-form over apath incylindrical coordinatesSuppose we want to integrate the1-form over the unit circle in the-plane.Wewant tochange variables fromto,so that we parameterize the unitcircleas.The integralis14CHAPTER 1.ELECTROSTATICSWe could have guessed the result by noting that each surface of pierced by the path in the positive direction(such that the orientation of the surface is the same as the counterclockwise direction of integration along the path)is canceled when the path pierces the same surface in the negative direction.1.32-forms,3-forms,and the Exterior ProductAs we showed in the introduction to this chapter,a 2-form is a quantity which is integrated over a two–dimensional surface.The quantity representing flow of a fluid,for example,has units of flow rate per area,and would be integrated over a surface to find the total flow rate through the surface.Similarly,the integral of electric flux density over a surface is the total flux through the surface,which has units of charge.A general 2-form is written as(1.7)The wedge between differentials is known as the exterior product .This product allows one to combine 1-forms to produce differential forms of higher degree.The 2-form ,for example,is the exterior product of the 1-formsand .The exterior product has the important property that if two differentials are interchanged,the sign of theproduct changes.In other words,the exterior product of 1-forms is antisymmetric.For example,.Using this property,it is easily seen that the wedge product of two like differentials is zero:.Forconvenience,we usually use the antisymmetry of the exterior product to put differentials of 2-forms into right cyclic order,as in Eq.(1.7).Two 1-forms and can be added,so that if and are 2-forms,their sum is(1.8)Like 1-forms,2-forms have three independent components,and a correspondence between 2-forms and vectors can be made.A 2-form with differentials in right cyclic order can be converted in euclidean coordinates to a vector as follows:(1.9)The 2-form is said to be dual to the vector .Example 1.3.Exterior product of 1-forms.Let and .ThenThis 2-form is dual to the cross product .Example 1.4.Exterior product of a 1-form and a 2-form.Let and .ThenThe result is a 3-form.The coef ficient of this 3-form is equal to the dot product.We will discuss 3-forms in greater detail below.1.3.2-FORMS,3-FORMS,AND THE EXTERIOR PRODUCT 15(a)x zyFigure 1.18:The2-form integrated over a squareinthe –plane of side2-forms are integrated over areas,or two–dimensional regions of space.When a 2-form appears under an integral,we often drop the wedgesforconciseness:(1.10)2-forms are graphically represented as tubes.Thepictureof consists ofthesurfaces of superimposed withthesurfaces of .The sets of surfaces intersect to form tubesin the direction.The integral of a 2-form over an area is the number of tubes crossingthearea.For ,the integral over asquare inthe –plane of side is 4,and as shown in in Fig.1.18,nine tubes cross this square.The greater the components of a 2-form are in magnitude,the smaller and more dense are the tubes of the 2-form.As with 1-forms,the tubes of a 2-form have an orientation.Thetubesof ,for example,areorientedin the direction,whereasthetubesof are orientedin the direction.Areas of integration also have an orientation,since their are two possible normal directions for any area.The limits of a double integral specify a direction around the perimeter,and the right–hand rule applied to this direction speci fies the orientation of the area.When integrating graphically,we compare the orientation of each tube with the orientation of the area of integration,and the tube counts positively if the orientations are the same,and negatively otherwise.1.3.12-forms in Curvilinear CoordinatesIn general curvilinear coordinates,the unit differentialfor 2-formsare,,and .If the2-form is integrated over a surface whichlies inthe -plane,thenthefactor is such that the value of the integral is equal to the area of the surface.The unit differentials are dual to theunitvectors ,,and .In the cylindrical coordinate system,2-forms and vectorsarerelatedbyThe2-form ,for example,is dual tothevector .In the spherical coordinate system,2-forms and vectorsarerelatedby The2-form ,for example,is dual tothevector .Example 1.5.Integrating a 2-form using spherical coordinates。

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A choice of flow primary linings affords further protection against coating and high sediment flows, with users able to choose from a variety of materials, including ceramic linings for particularly abrasive flows.The ability of electromagnetic flowmeters to better handle distorted velocity profiles also reduces the amount of piping upstream and downstream of the meter.Modern electromagnetic flowmeters are also capable of being buried, eliminating the need for the construction of costly installation chambers.Available in sizes from 10 to 2400 mm (3/8 to 96 in), ABB’s WaterMaster electromagnetic flowmeter is ideally suited to wastewater flow measurement applications.A key feature is the WaterMaster’s revolutionary octagonal sensor design. By improving the flow profile, the octagonal design minimizes the upstream and downstream pipe lengths required from the point of installation, greatly reducing the cost of fitting the meters into new or existingpipelines.3 ACCU R ATE WA S TE WATE R F LOW M E A S U R E M E NT | WATER M A S TER| A D/FLOW/006–EN R E V. AABB’s WaterMaster electromagnetic flowmeter enables operators to gain an enhanced overview of their wastewater flows.The WaterMaster also features on-board verification capability. Called VeriMaster, it assures operators of the performance of the meter through constant self-checking. When coupled with ABB’s VeriMaster software tool, it enables operators to produce a printed verification certificate for regulatory compliance.The effects of signal noise are also minimized by the WaterMaster’s use of advanced Digital Signal Processing (DSP) technology. This enables the WaterMaster’s transmitter to separate the real signal from the noise, thereby providing high quality outputs especially in harsh environments involving vibration, hydraulic noise and temperature fluctuation.All WaterMaster sensors have a rugged, robust construction to ensure a long, maintenance-free life even under the most difficult conditions experienced in water and waste water applications. The sensors are inherently submersible (IP68, NEMA 6P) as standard, ensuring suitability for installation in chambers and metering pits which are liable to flooding.All sizes of the WaterMaster are buriable and are straightforward to install, with installation merely involving excavating to the underground pipe, installing the sensor and wiring the factory pre-potted cabling to the transmitter and then backfilling the hole. Operation has been simplified by the use of ABB’s universal Human Machine Interface (HMI), which has now been extended across its range of instrumentation products. Based on Windows™ technology, the HMI simplifies operation, maintenance and training, reducing cost of ownership and providing a consistent user experience. Data can also be accessed remotely via HART™, Profibus DP™ and Modbus™ communications.Installation is further simplified by the WaterMaster’s ‘Fit and Flow’ data storage feature. On initial installation, the selfconfiguration sequence automatically replicates into the transmitter all calibration factors, meter size and serial numbers as well as customer site-specific settings. This eliminates the opportunity for errors and leads to increased speed of start-up.Measurement integrity is ensured by redundant storage of data in both the sensor and transmitter memory, which is continually updated during all operations. The on-board sensor memory eliminates the possible problems associated with pluggable data memory modules.WaterMaster is proven to be robust and reliable, with unmatched diagnostic capabilities providing the right information to keep the process up and running. Alarms and warnings are classified in accordance with NAMUR NE107.The meter is also verified to OIML R49 type ‘P’ requirements to ensure the highest accuracy and long term performance of the system by continuously self-checking the sensor and transmitter in the field.All ABB flow meters are designed and manufactured in accordance with international quality procedures (ISO 9001) and are calibrated on nationally-traceable calibration rigs to provide the end-user with complete assurance of both quality and performance. Acknowledgments• HART is a registered trademark of the FieldComm Group • Modbus is a registered trademark of Schneider Electric USA Inc.• PROFIBUS is a registered trademark of PROFIBUSorganization.A D /F L O W /006-E N R e v . A 02.2019—ABB LimitedMeasurement & Analytics Oldends Lane StonehouseGloucestershire GL10 3TA UKTel: +44 (0)1453 826 661Fax: +44 (0)1453 829 671Email: **********************.com ABB Inc.Measurement & Analytics 125 E. County Line Road Warminster PA 18974USATel: +1 215 674 6000Fax: +1 215 674 7183ABB Engineering (Shanghai) Ltd.Measurement & Analytics No. 4528, Kangxin Highway Pudong New District Shanghai, 201319,P.R. ChinaPhone: +86 (0)21 6105 6666Fax: +86 (0)21 6105 6677Email:****************************.com /measurement—We reserve the right to make technical changes or modify the contents of this document without prior notice. With regard to purchase orders, the agreed particulars shall prevail. ABB does not accept any responsibility whatsoever for potential errors or possible lack of information in this document.We reserve all rights in this document and in the subject matter and illustrations contained therein. Any reproduction, disclosure to third parties or utilization of its contents – in whole or in parts – is forbidden without prior written consent of ABB.©ABB 2019All rights reserved.。

光不能穿过物体英语作文Title: The Phenomenon of Light Not Passing Through Objects。

Introduction:The phenomenon of light being unable to pass through certain objects is a fascinating aspect of physics that has intrigued scientists and thinkers for centuries. Whilelight is often considered as an omnipresent force capable of penetrating through various mediums, there exist materials that can block or obstruct its passage. In this essay, we will explore the science behind this phenomenon, its practical implications, and its significance in our understanding of the natural world.Understanding Light and Matter:Light, as we know it, travels in the form of electromagnetic waves. These waves propagate through spaceuntil they encounter an obstacle or a medium with different optical properties. When light interacts with matter, several processes can occur, including reflection, refraction, absorption, and transmission. The ability of a material to allow light to pass through it depends on its molecular structure and the energy levels of itsconstituent particles.Factors Affecting Light Transmission:The transmission of light through a material depends on various factors, including the wavelength of light, the density of the material, and its chemical composition. Materials such as glass, air, and water are transparent to visible light because their molecular structures allow photons to pass through relatively unhindered. On the other hand, opaque materials like metals and dense ceramicsabsorb or reflect light, preventing it from passing through. Mechanisms of Light Blocking:The inability of certain materials to transmit lightcan be attributed to different mechanisms. In some cases, the atoms or molecules in the material absorb the photons, converting their energy into internal vibrations or electronic transitions. This absorption process effectively prevents the light from propagating through the material. In other cases, the material may scatter or reflect light due to irregularities in its structure, further inhibiting its transmission.Applications and Implications:The phenomenon of light blocking has numerous practical applications across various fields. In architecture and design, opaque materials are used to create privacy and control the amount of light entering a space. In photography and imaging, the manipulation of light-blocking materials allows for the creation of shadows, contrasts, and artistic effects. Moreover, in industries such asoptics and telecommunications, the development of materials with specific light-blocking properties is crucial for the fabrication of lenses, filters, and optical fibers.Scientific Significance:The study of materials that block light not only has practical applications but also contributes to our understanding of fundamental physical principles. By investigating the interaction between light and matter at the atomic and molecular levels, scientists gain insights into the behavior of photons and the electronic structure of materials. This knowledge is essential for advancing fields such as quantum mechanics, photonics, and materials science.Conclusion:In conclusion, the phenomenon of light being unable to pass through certain objects is a complex yet intriguing aspect of physics. Through the study of light-blocking materials, scientists have gained valuable insights into the nature of electromagnetic waves and the behavior of matter at the atomic scale. Moreover, the practical applications of this phenomenon underscore its significance in everyday life, from architecture and design totelecommunications and scientific research. As our understanding of light and matter continues to deepen, so too will our ability to harness and manipulate these phenomena for the benefit of society.。

发电机线圈匝数与电压公式物理1.发电机线圈的匝数与电压之间存在着直接的关系。

The number of turns of the generator coil is directly related to the voltage.2.发电机线圈的匝数增加，所产生的电压也随之增加。

As the number of turns of the generator coil increases, the generated voltage also increases.3.发电机线圈的匝数减少，则所产生的电压也相应地减少。

If the number of turns of the generator coil decreases, the generated voltage will also decrease accordingly.4.电压与线圈匝数的关系可用数学公式表示。

The relationship between voltage and coil turns can be expressed by a mathematical formula.5.发电机线圈的匝数是影响电压大小的重要因素之一。

The number of turns of the generator coil is one of the important factors affecting the voltage.6.通过改变发电机线圈的匝数，可以调节所产生的电压大小。

By changing the number of turns of the generator coil,the generated voltage can be adjusted.7.发电机线圈的匝数与磁场的变化也会影响到所产生的电压。

The number of turns of the generator coil and the changein the magnetic field also affect the generated voltage.8.在设计发电机时，需要考虑线圈的匝数对电压的影响。

Standard R1Environmental Design &Testing of Electronic & Electrical ComponentsTable of Contents 目錄1. SCOPE AND DEFININTIONS范圍與述語定義2. APPLICATION 應用3. ENVIRONMENTAL FACTORS, TEST METHODS AND GENERAL GUIDELINES環境及測試方法的指導4. DEVIATIONS 偏差5. TESTING AND INSTRUMENTATION ACCURACY 測試和儀器精確度6. ELECTRICAL REQUIREMENTS 電子要求6.1 LOAD DUMP 甩負荷測試6.2 ELECTROSTATIC DISCHARGE (ESD) 抗ESD干擾測試(ASA做< JONNY19.12.07復> )6.3 DC VOLTAGE OVERSTRESS DC電壓負荷測試6.4 REVERSE BATTERY 電池反接測試6.5 INDUCTIVE LOAD SWITCHING TRANSIENT VOLTAGE 感應負載切換瞬時電壓測試(ASA做<JONNY19.12.07復> )6.6 MUTUAL COUPLING TRANSIENT VOLTAGE 互耦瞬時電壓測試 (ASA做< JONNY19.12.07復> )6.7 SHORTED I/O 短接I/O測試6.8 POWER SUPPLY/ALTERNATOR RIPPLE REJECTION 拒絕電源紋波測試(ASA做< JONNY19.12.07復> )6.9 SIMULATED CRANK-START VOLTAGE 模擬曲柄啟動電壓(ASA做< JONNY19.12.07復> )7.1 LOW OPERATING VOLTAGE 低電壓操作。

高频电磁场环境对电子器件的影响研究IntroductionWith the development of modern technology, electronic devices have become an indispensable part of our daily life. However, the increasing use of electronic devices in our life has led to the emergence of a new challenge - electromagnetic radiation interference. High-frequency electromagnetic fields are generated by a wide range of sources, such as communication systems, power lines, and electronic devices. These high-frequency electromagnetic fields can interfere with the normal operation of electronic devices, affecting their performance and reliability. Therefore, it is essential to research the impact of high-frequency electromagnetic fields on electronic devices.Effect of High-Frequency Electromagnetic Fields on Electronic Devices1. Electromagnetic InterferenceThe electromagnetic interference (EMI) phenomenon is a significant challenge for electronic devices that operate in a high-frequency electromagnetic environment. This interference can significantly affect the performance of electronic devices, leading to malfunction or even failure. EMI can be induced by external sources of electromagnetic fields or generated internally within devices.External EMI can be caused by devices such as broadcast transmitters, cell phones, and radios. On the other hand, internal EMI can arise from the circuitry within the electronic device itself, such as clock signals, switching transistors, or inductive loads.2. Radiation EffectsRadiation effects are associated with the impact of high-energy particles, including electromagnetic radiation, on electronic devices. These effects can cause single-event upsets (SEUs), which are essentially errors that occur when high-energy particles strike a sensitive region of a device, such as a transistor or memory cell.SEUs are critical concerns for electronic devices that operate in high-altitude environments, such as satellites or aircraft. These electronic devices must be designed with special protective measures to avoid SEUs.3. Signal IntegritySignal integrity refers to the ability of electronic devices to maintain the correct signal quality within their operating environment. Signal integrity issues can result from a variety of factors, including noise, distortion, and crosstalk. High-frequency electromagnetic fields can often cause signal integrity issues by creating noise or crosstalk and degrading the signal quality.Methods to Evaluate the Impact of High-Frequency Electromagnetic Fields on Electronic Devices1. Experimental ApproachesExperimental techniques are commonly used to evaluate the impact of high-frequency electromagnetic fields on electronic devices. In the laboratory, devices are subjected to a range of electromagnetic fields, and their performance is evaluated. The effectiveness of this approach depends on the ability to accurately replicate the real operating conditions of the device.2. Modeling and SimulationModeling and simulation techniques allow for the evaluation of the impact of high-frequency electromagnetic fields on electronic devices in a virtual environment. These techniques are particularly useful for complex devices or systems that are challenging to analyze experimentally.Modeling and simulation can help to identify the most significant sources of EMI and suggest possible solutions. It is possible to use different types of simulation techniques, such as finite element method (FEM), finite-difference time-domain (FDTD), or integral equation methods.3. Design ConsiderationsDesign considerations play a significant role in mitigating the impact of high-frequency electromagnetic fields on electronic devices. One of the primary design considerations is the selection of appropriate components. Components with high noise immunity, such as shieldedcables or filters, may be used to minimize the impact of high-frequency electromagnetic fields.Another design consideration is the implementation of electromagnetic shielding, which is intended to minimize the penetration of electromagnetic fields into the device. Shielding can be achieved using conductive materials, such as copper or aluminum foil.ConclusionThe impact of high-frequency electromagnetic fields on electronic devices is a significant concern that must be taken seriously in modern technology. The effects of EMI, radiation, and signal integrity issues can cause severe problems, including device failure or malfunction. Experimental techniques, modeling, and simulation, and design considerations are all essential tools for evaluating these effects and developing solutions. By taking these factors into consideration, electronic devices can be designed and operated with greater reliability in high-frequency electromagnetic fields.。

外星人和地球人的不同英语作文Humanity has long been fascinated by the prospect of extraterrestrial life. From science fiction stories to serious scientific speculation, the idea of intelligent beings from other worlds has captured our collective imagination. As we continue to explore the cosmos and search for signs of life beyond our planet, it is natural to wonder about the potential differences between extraterrestrials and the inhabitants of Earth. While we can only speculate about the nature of alien civilizations, there are several key areas where we might expect to find significant contrasts between extraterrestrials and earthlings.One of the most fundamental differences would likely be in the area of biology and physiology. Depending on the conditions of their home planet, extraterrestrials could have vastly different physical characteristics compared to humans. Their biochemistry, anatomy, and even sensory capabilities might be radically different from our own. For example, an alien species might possess additional limbs, organs, or sensory organs that we cannot even conceive of. Their means of locomotion could be completely foreign to us, perhapsinvolving levitation, flight, or a mode of movement that is entirely alien to terrestrial life.The way extraterrestrials perceive and interact with their environment could also be profoundly different from human experience. Their senses might operate on wavelengths of the electromagnetic spectrum that are invisible to us, allowing them to detect phenomena that are imperceptible to human eyes, ears, and other senses. They may have sensory capabilities that we cannot even imagine, giving them an entirely different understanding of their surroundings. Additionally, the cognitive processes and decision-making strategies of extraterrestrials could be radically different from our own, shaped by the unique evolutionary pressures and environmental conditions of their home world.Another key area of potential difference is in the realm of language and communication. The development of language on Earth has been shaped by the specific biological and cultural characteristics of human societies. Extraterrestrial civilizations, however, may have evolved radically different systems of communication, perhaps involving non-verbal modes of expression or even forms of communication that transcend the limitations of our own spoken and written languages. Their "languages" could be based on entirely different principles, utilizing novel modes of information transmission that are foreign to us. This could present significantchallenges in terms of mutual understanding and interspecies communication.The social and cultural structures of extraterrestrial civilizations are also likely to be quite different from those found on Earth. The specific environmental, technological, and historical factors that have shaped human societies may not apply to alien worlds, leading to the development of social organizations, political systems, and cultural practices that are vastly different from our own. Extraterrestrials may have radically different value systems, modes of conflict resolution, and approaches to decision-making and resource allocation. Their concepts of individuality, community, and the role of the individual within society could be fundamentally alien to us.Furthermore, the technological capabilities of extraterrestrial civilizations could be far beyond our current understanding and level of development. While we often envision aliens as possessing advanced technologies that are indistinguishable from magic, the reality may be even more profound. Extraterrestrials may have mastered forms of energy, matter manipulation, and information processing that are completely foreign to human experience. Their technological prowess could allow them to transcend the limitations of their physical form, perhaps even achieving a level of post-biological existence that is difficult for us to comprehend. The ways in which they harness and apply technology could be so radicallydifferent from our own that meaningful comparisons become nearly impossible.Finally, the worldviews and belief systems of extraterrestrial civilizations may be radically different from those found on Earth. Their philosophical and spiritual perspectives could be shaped by entirely different cosmological understandings, with vastly different conceptions of the nature of reality, the origins of the universe, and the place of intelligent life within it. Their approaches to questions of ethics, morality, and the meaning of existence could be profoundly alien to human thought, perhaps even challenging our most fundamental assumptions about the nature of consciousness and the human condition.In conclusion, the potential differences between extraterrestrials and earthlings are vast and multifaceted. From the realm of biology and physiology to the domains of language, social structures, technology, and worldviews, the contrasts between alien civilizations and human society could be staggering. As we continue to explore the cosmos and search for signs of life beyond our planet, it is important to maintain an open and flexible mindset, recognizing that the diversity of intelligent life in the universe may be far greater than we can currently imagine. Embracing this potential for radical difference will be crucial as we navigate the challenges and opportunities presented by future encounters with extraterrestrial civilizations.。

猫眼效应中离焦量对激光回波发散角的影响李会;陈青山;李晓英;刘力双【摘要】平行光束或者激光束在光轴方向上照射焦平面成像系统时会产生猫眼效应,焦平面探测器安装的正交性与离焦量直接影响猫眼回波的光学特性,进而影响基于猫眼效应的探测系统的性能.针对猫眼效应中离焦量与后向反射光束发散角之间关系,利用物理光学进行分析,建立理论模型,对焦距为0.18m的焦平面探测成像系统进行数值计算得到:在离焦量为0.16 mm时,发散角最小(0.019 mrad).搭建实验系统,测试离焦量与猫眼回波发散角,测得离焦量在0.15 mm附近存在最小的发散角为0.025 mrad,与计算结果0.019 mrad基本吻合.研究表明:1)负离焦对发散角的影响大于正离焦;2)猫眼回波发散角基本上随着离焦量绝对值的增加而变大,但是变化曲线并不关于零离焦量点对称,而是在某个正离焦处存在一个最小发散角.【期刊名称】《应用光学》【年(卷),期】2016(037)001【总页数】5页(P147-151)【关键词】猫眼效应;离焦量;发散角;焦平面【作者】李会;陈青山;李晓英;刘力双【作者单位】北京信息科技大学仪器科学与光电工程学院,北京100192;北京信息科技大学仪器科学与光电工程学院,北京100192;北京信息科技大学仪器科学与光电工程学院,北京100192;北京信息科技大学仪器科学与光电工程学院,北京100192【正文语种】中文【中图分类】TN249平行光束或者激光束在光轴方向上照射焦平面成像系统时，能够产生按原路返回的准直回光,即所谓“猫眼效应”[1]。

通过探测光电设备的光学窗口能够实现对目标的快速准确定位[2]，根据“猫眼”目标的回波功率大约是背景漫反射功率的102～103倍可实现对“猫眼”目标的探测[3]，因此深入分析“猫眼”目标回波发散角具有很高的研究价值[4]。

对于实际光学系统，由于元件加工误差原因，光敏面不一定正好位于焦平面上[5]，甚至为了特殊需要，人为设置一定的离焦量，而且一般的光学系统由于像差等原因的存在，对于轴外入射光而言也往往存在离焦[6]。

电科专业英语复习资料T ext1_Exercise? 1.the microprocessor is the central①component（部件）of the PC.? 2.Reliability and Stability:The quality of the processor is one factor thatdetermines②how reliably your system will run（系统运行的可靠性）.While most processors are very③dependable （可靠的）,some are not.This also depends④to some extent（在某种程度上）on the age of processor and how much energy it⑤consumes（消耗）.? 3.Flash memory is a①solid state(固态的)storage device-everything is②electronic（电子的）.Flash memory provides a③non-volatile（非易失的），reliable,low power,low cost,④high density（高密度）storage device for programmable⑤code and data（代码和数据）,making it extremely useful in the⑥embedded(嵌入式)marketplace.翻译：? 1.芯片是嵌入了集成电路的一小片半导体材料。

? 1.A chip is a small piece of semiconducting materialon which an integrated circuitis embedded.?2.典型芯片不足1平方英寸，却能包含几百万个晶体管。

线路板emc检测标准When it comes to EMC testing standards for printed circuit boards, it is essential to understand the importance of compliance with such regulations. EMC, or electromagnetic compatibility, testing is crucial in ensuring that electronic devices perform as intended without interfering with other devices or being susceptible to interference from external sources. The standards for EMC testing set forth by various regulatory bodies serve to protect consumers, manufacturers, and the overall functioning of electronic devices in the market.在谈到线路板的EMC测试标准时，理解遵守这些规定的重要性至关重要。

EMC，即电磁兼容性，测试对于确保电子设备在不干扰其他设备或受到外部干扰的情况下正常工作至关重要。

各种监管机构制定的EMC测试标准旨在保护消费者、制造商以及市场上电子设备的正常运作。

Not only do EMC testing standards ensure the proper functioning of electronic devices, but they also play a significant role in promoting safety and reliability. By adhering to these standards, manufacturers can minimize the risk of malfunctions, electrical interference, and potential hazards that could harm users or the environment.Compliance with EMC regulations is necessary for market acceptance and legal requirements, as non-compliance can lead to costly recalls, damage to reputation, and even legal consequences.EMC测试标准不仅确保电子设备的正常工作，还在促进安全性和可靠性方面发挥重要作用。

材料科学专业英语词汇(E)e.b.m (electron beam machining)电子束加工，电刻e.c.m. (electrochemical machining)电化加工e.d.m (electrical discharge machining)放电加工earing 成耳(冲压)early-strenghth cement 早强水泥earth bar/grounding bar 接地棒earthenware 陶器；瓦器easy fired 易烧easy glide plane 易滑面easy-flo 易流硬焊料(含ag50%,cd18%,su16.5%,cu15.5% 之四元共晶)eaves tile 詹瓦ebonite 硬橡胶(皮)eccentric converter 偏心转炉eccentric upset forging 偏心锻粗eccentric upsets 偏心锻粗件eccentric upsetting 偏感锻粗法economizer[ 锅炉]节热器eddy current 涡[电]流eddy current loss 涡[电]流损失eddy current method 涡电流法eddy current test 涡[电]流试验edge bead removal /e.b.r 边缘球状物去除edge bending 侧向弯曲edge crack 边缘裂纹edge dislocation 刃差排edge exclusion 周边除外范围edge lining 钩边edge polisher 边缘抛光机edge runner 混砂机edge sensor 边缘感测器edge-runner mill 轮辗机edger 磨边器，成边器edging 磨边，成边edging impression 成边型edging stone 磨边路eds testeds 测试effective aperture 有效孔径effective case depth 有效硬化深度effective strain 有效应变effective stress 有效应力efferrescing steel (同rimming steel)赤静钢efficiency of target utilization 靶子利用效率efflorescence 粉化；吐霜efflorwick test 吓霜试验effluent 流出物eggert'stube 爱格特管(快速比色，测钢中之碳用) eggshell porcelain 蛋壳簿瓷eggshelling 蛋壳耳(搪瓷)(陶)einsteinium (es,99)金爱ejecter 拆卸器ejection 顶出ejector1 顶出器2.喷射器ejector plate 顶出板elastic after-effect 弹性余效elastic constant 弹性常数elastic constraint 弹性抑制elastic deflection 弹性挠曲elastic deformation 弹性变形elastic emission machining 弹性碰撞机械加工elastic fatigue 弹性疲劳elastic hardness 弹性硬度elastic hysteresis 弹性迟滞elastic limit 弹性限elastic medium 弹性媒质elastic modulus 弹性模数，弹性系数elastic reactance 弹性抗elastic strain 弹性应变eldred's wire 爱瑞得导线(镀铜，镍铁心封於玻璃内之导线) electret 驻极[电介]体electric arc furnace 电弧炉electric arc welding 电弧熔接electric flame off 电火炬electric furnace 电炉electric furnace iron 电炉生铁electric furnace steel 电炉钢electric furnace steel making 电炉炼钢electric induction 电感应electric induction furnace 感应电炉electric micrometer 电测分厘卡electric porcelain 电瓷electric precipitation 电力析出electric resistance furnace 电阻炉electric resistance heater 电阻加热器electric resistance strain gage 电阻应变计electric resistance thermometer 电阻温度计electric resistance welding 电阻溶接electric spark maching 放电加工(同e.d.m)electric steel 电炉钢electric welding 电熔接，电焊electric-arc cutting 电弧切割electric-furnace ferrosilicon 电炉矽铁electrical dipole 电隅极electrical discharge machine (edm)电蚀机，放电加工机electrical heating 电加热electrical resistivity 电阻率electrical rule check 电器法则查验electro graphy 电蚀刻electro hydralic forming 电液成型electro striction 电致伸缩electro-deposited coating 电积层electro-deposition 电 [淀]积electro-forming 电铸electro-luminescence method 场致发光法electro-migration check 电性选移查检electro-migration test 电性迁移试验electro-osmosis 电渗electro-osmosis (或electro smose)电渗透作用electro-phoresis 电泳electro-plating 电镀electro-slag refining (esr)电渣精炼electro-type metal 电铸版合金electrocast refractory 电铸耐火材料electroceraimcs 电用陶瓷electrochemical corrosion 电化腐蚀electrochemical cyaniding 电解氰化electrochemical equivalent 电化当量electrochemical grinding 电化研磨electrochemical series 电化序electrocoating 电咏护膜，电着护膜electrode materials 电极材料electrode potential 电极电位electrode ring 电极环electrodeposition 电[淀]积electroformed diamond blade 电铸钻石刀片electrofusion 电熔electrokinetics 动电常electroless plating 无电镀金electrolysis 电解electrolysis treatment 电解处理electrolyte 电解质electrolytic cell 电解电池electrolytic cleaning 电解清洁法electrolytic copper 电解铜electrolytic de-rusting 电解去锈electrolytic deflash 电解树脂残渣去除electrolytic discharge aided grinding machine 电解放电辅助研磨机electrolytic dissociation 电[解]离解electrolytic etching 电 [解]浸蚀electrolytic hardening 电[解]硬化electrolytic ionized water /electrolysis-ionized water 电解电离水electrolytic iron 电解铁electrolytic pickling 电解浸洗electrolytic polishing 电解抛光electrolytic powder 电解粉未electrolytic protection 电解防蚀法electrolytic refining 电解精炼electrolytic solution tension 电解溶压electrolytic toughpitch copper 电解勒炼铜electrolytical series 电解序列electromagnet 电磁体，电磁铁electromagnetic forming 电磁成形electromagnetic lens 电磁透镜electromagnetic wave 电磁波electromechanical polishing 电解机械抛光electrometallurgy 电化冶金，电冶学electromotive force series 电动势序electron alloy 伊兰镁合金(含铝锌镁基合金)electron balance 电子天秤electron beam 电子束electron beam annealer 电子波束退火处理机红electron beam cell mask 电子束功能电路胞光罩electron beam control 电子束控制electron beam evaporation system 电子束蒸镀系统electron beam exposure system 电子波束曝光系统electron beam melting furnace 电子束熔解炉electron beam prober 电子波束探针electron beam test system 电子波束测试系统electron beam welding 电子束熔接electron beam zone-refining 电子束区带精炼electron cloud 电子云electron compound 电子化合物electron configuration 电子组态electron coupling resonance (ecr)plasma enhanced cvd systemecr 等离子体增强型cvd 系统electron coupling resonance (ecr)sputtering system 电子耦合谐振溅镀系统electron cyclotron resonance 电子回旋加速器共振electron cyclotron resonance etching system 电子回旋加速器共振蚀刻系统electron diffraction pattern 电子绕射图electron diffratction 电子线绕射electron flood gun 淹没式电子枪，电子流枪electron furnace iron 电炼生铁electron gun 电子枪electron lens 电子透镜electron microscope 电子显微镜electron negative potential 电子负电位electron optics 电子光学electron pair 电子隅electron photomicrograph 电子显微照片electron probe micro analysis 电子探针微分析electron probe microanalysis 电子探针分析electron probe microanalyzer 电子探测显微分析仪electron ratio 电子比electron shading effect 电子遮掩效应electron spin 电子自旋electron suppressor 电子抑制器electron volt 电子伏特electron wave 电子波electronic charge 雯子电荷electronic design automation（eda）电子设计自动化electronic design interchange format（edif）电子电路设计互换格式electronic polarization 电子极化electronic system design automation tool 电子系统自动设计工具electrophoresis 电咏electrophoretic plating 电咏镀electropositive potential 正电位electroslag remelting process 电渣再熔法electroslag welding 电渣熔接electrostatic chuck 静电夹头，静电夹盘electrostatic discharge protection 静电放电保护electrostatic fluidized bed 静电浮床electrostatic mineral separation 静电矿物分离机electrostatic precipitation 静电沉积electrostatic scan 静电扫描electrostatic separation 静电分离electrostatic spraying 静电喷涂electrothermal equivalent 电热当量electrothermic method 电热法electrotype 电铸板electrotyping 电铸版术electrovalent compound 电价化合物electrowinning 湿式电冶eletrode1. 电极2.熔接条eletrum 白黄金(40-50%au, 其余为ag)elevator kiln 升降窑elevator unit 升降机单元elinvar [steel] 恒弹性钢elphal 依尔花法，钢皮差面沉积纯铝法eluant solution 洗涤液elutriation 淘析(液体中分离大小，粉未颗粒的方法)email sur bisque 素三彩emaillieuen 插画珐琅embeded array 埋入行阵列embeded system 埋入型系统embossing 浮花压制法压凸embrittlement 脆性emerg colth[ 金钢]砂布emerg paper[ 金钢]砂纸emergizer 促进剂(渗碳)emery 钢砂，钢石粉emission electrton microscope 发射电子显微镜emissivity 发射率emissivity correction 发射率校正emitter 射极empirical proportioning 经验配合emulator 模拟除错器emulsified oil quenching 乳化油卒火emulsion 乳液，乳胶emulsion cleaner 乳化清洁剂enamel1. 搪瓷2.瓷漆enamel coating 搪瓷护膜enamel color 珐琅色彩enamel glaze 珐琅釉enamel paint 瓷漆enameled iron ware 搪瓷[铁]器enameled wire 漆包线enamelling 施珐琅；搪瓷enamelling iron 搪瓷胎铁encapsulation 封装enclosure 夹杂物，包壳encoustic tile 彩纹瓦end arch 端拱砖end chipping 最终结晶屑end skew 端斜砖end wall 端墙end-station 终端站endless band saw 环型条带锯endothermic gas 叹热型气体(热处理保护气) endothermic reaction 吸热反应endurance limit (fatingue limit)疲劳限endurance ratio 疲劳比endurance strength 疲劳强度endurance test 疲劳试验enduron 安久乐(一悝含铬钼矽之铁系耐蚀合金) energy band 能带energy contamination 能量污染，杂质能量energy gap 能隙energy level 能阶，能准位energy packet 能，束enfield rolling mill 恩菲德巴钢机engine-turning lathe 机动车床engineering change order 工程变更次序engineering work station（ems）工程工作站english 中文english bond 英式砌法english crystal 高铅水晶玻璃english white 白垩engobe 化粧土；釉底料engravers brass 刻版黄铜(一种含铅黄铜) engraving 刻花enhanced global alignment 增强型全晶圆调准enriched uranium 浓缩铀enrichement 浓缩enthalpy 焓entrained air 输气(混凝土)entrapped air 陷入空气(混凝土)entropy 熵environment control 环境控制environmental scanning electron microscope 环境控制扫描型电子显微镜epitaxial growth 叠晶生长，同轴生长(晶体)epitaxial growth system 磊晶生长系统epitaxial wafer 磊晶晶圆epithermal neutrons 超热中子(具有在分裂中子与热中子间能量之中子)epoxy resin 环氧树鲁epsilon carbideε 碳化物epsilon compoundsε 佮合物(电子比为7:4，例如cuzn3)equations of state 状态方程式equi-blast cupola 等吹熔铁炉equiaxial polytggonal grain 等轴多角形晶粒equicohesive temperature 等结合温度(晶粒内晶粒界强度相等时之温度)equigranular 等粒状equilibrium (phase)平衡equilibrium diagram 平衡图equilibrium potential 平衡电位equilibrium segregation 平衡偏析equilibrium segregation coefficient 平衡偏析系数equilibrium state 平衡状态equivalence factors 当量因素equivalent fault 等效故障equivalent section 比量断面equivalent weight 当量equlibrium 平衡erase error 删除错误erase error allowance 删除错误容限erase fail 删除失误erbium (er,68)铒erichsen [cupping] test 爱理逊压凹试验ermalite 艾马来铁(高延性铸铁)ernst hardness tester 恩氏硬度计erosion 冲蚀erosion-corrosion 阵蚀，腐蚀erosion-resistrance 耐冲蚀性erubescite 硫铜石，斑铜矿(cu2fes3)ester 酯estimated wire length 估计布线长度etch back 回蚀etch bands 浸蚀带etch fiqure 蚀迹etch pit density 腐蚀坑密度etch rate 蚀刻速率etch residue 蚀刻残余物etch selectivity raito 蚀刻选择比，蚀刻选择性etch uniformity 蚀刻均质性etchant 浸蚀液，蚀刻液etched wafer 经蚀刻晶圆etching1 蚀刻2浸蚀etching chamber 蚀刻处理室etching end point detection 蚀刻终点检测etching pit 蚀乙etching system 蚀刻系统etching wafer 刚蚀刻晶圆ethyl silicate 矽乙酯ettinghausen effect 埃丁赫逊效应(晶体之一种物理效应) eucryptite 锂霞石eureka 尤瑞卡铜(电阻线之一种，近似康史登铜) europium (eu, 63)铕eutectic 共晶eutectic alloy 共晶合金eutectic bonding 共晶接合eutectic carbide 共晶碳化物eutectic cast iron 共晶铸铁eutectic cell 共晶单胞eutectic cementite 共晶雪明碳体(铁)eutectic colong 共晶集团eutectic graphite 共晶石墨eutectic mixture 共晶混合物eutectic reaction 兆晶反应eutectic temperature 共晶温度eutectoid 共析eutectoid alloy 共析合金eutectoid cementite 共析雪明碳体(铁)eutectoid composition 共析成分eutectoid ferrite 共析肥粒体(铁)eutectoid hardening 共析硬化eutectoid line 共析线eutectoid point 共析点eutectoid reaction 共析反应eutectoid steel 共析钢eutectoid structure 共析组织eutectoid temperature 共析温度eutectoid transformation 共析变态evacuated wet etching system 减压抽气浸渍式蚀刻系统evanohm 艾文姆台金(一种镍铬铝铜合金) evaporation coefficient 蒸发系数evaporation loss 蒸发损失evaporation material 蒸发材料evaporation ratio 蒸发比evaporation source 蒸发源event driven simulator 事件驱动模拟器everdur 艾未狄合金(一种矽青铜)ewald chart 厄互特图(x-ray)exb magnetron sputtering system 直交电磁场型溅镀系统excavator 挖掘机exchange energy 互换能exchange force 互换力exchange-cunent density 交换电流密度excimer laser stepper 准分子雷射步进机excitation 激发，激励exciting level 激励准位excluding backside deposition 防止背面沉积exclusing backside deposition 防止背面沉积exfoliation 表皮脱落exhaust for developer 显影剂排放exhaustion creep 耗竭潜变exogenous metallic inclusion 外来金属夹杂物exothermic reaction 放热反应exothermic-base atmosphere 放热式蒙气，放热式炉器expand stage 黏胶片扩展夹片台expanded metal 展成金属(网)expanded r-field 扩张r 区expanding metals 胀大金属(铋合金)expansion 展开expansion coefficient 膨胀系数expansion ratio 晶圆黏胶片扩展率expansion scab 膨胀剥砂expectation value pattern 期待值图案expected pattern 预期图案explosibility 爆炸性explosion testing 爆炸试验explosion welding 爆炸熔接explosive antimony 爆炸锑explosive bonding 爆炸接合explosive forming 爆炸成形explosive pressing 爆炸压制exposed area ratio 蚀刻面积率，曝光面积率exposure 曝光extended dislocation 扩展差排extension board 延伸接线板；扩张接线板extensometer 伸长计external gettering 外部吸器external torch unit 外界火炬装置external upset 向外锻粗锻件external upset forging 向外锻粗external upsetting 向外锻粗法extra dense flint 特火石玻璃extra light flint 特轻火石玻璃extra-hard cold work 特硬级冷加工(冷巴至断面缩小50.0%) extra-spring-hared cold work 特弹簧硬冷加工(冷巴至断面缩小68.7%)extraction electrodes 提取电极extraction replica 萃取印模(电子显微镜)extraction voltage 提取电压extractive metallurgy 提炼冶金学extrapolation of creep data 潜变数据外推法extrinsic gettering 非本徵吸器extrinsic semi-conductor 他激半导体，他半导体extrudability 挤制性extruding 挤延extrusion1 凸出（疲劳滑动面）2挤裂extrusion cold 冷挤制extrusion, backward 逆向，挤制extrusion, forward 顺向，挤制extrusion, hydrostatic 液压挤制extrusion, impact 冲击，挤制extrusion, reducing 减缩，挤制eyelet 小孔eyeleting 小眼圈eyepies 目镜。

附录：常用专业词汇表Aabiotic adj.非生物的ablation n.消融abundant adj.丰富的;充足的abyssal adj.深不可测的abyssal plain n.深海平原accompany vt.陪伴;伴随accumulation n.堆积作用acid rain n.酸雨acres lost each year n.每年失去英亩数administer vt.管理;实施;执行Adriatic adj.亚得里亚海Aegean n.爱琴海aerospaceplane n.航天飞机aerosphere n.大气层afforestation n.造林Agenda 21 n.21世纪议程aggregate n.聚集agricultural modernization n.农业现代化agricultural system n.农业系统agriculture n.农业air mass n.气团air transport n.水路运输air flows and air masses n.气流和气团air pollution n.空气污染airport n.航空港Allah n.（回教语）安拉,真主alluvial fan n.冲积扇alluvial plain n.冲积平原Alps n.阿尔卑斯山脉alternation n.改变;变更altitude n.高度Amazon n.亚马孙河Amazon Basin n.亚马孙平原anabatic winds n.上升气流风Andes Mountains n.安第斯山脉angular speed n.角速度Antarctic Area n.南极地区anticyclone n.反气旋aphelion n.远日点Appalachian Mountains n.阿巴拉契亚山脉aquatic n.水生的Aral Sea n.咸海(中亚西亚地区) arctic adj.北极的Arctic Area n.北极地区arctic maritime adj.北极海洋的（ma）arid n.干旱arid environment n.干旱环境arid zones n.干旱地带artificial island n.人工岛asthenosphere n.软流圈atmosphere n.大气圈，大气atmospheric pressure n.气压atmospheric motion n.大气运动atoll n.环状珊瑚岛；环礁atoms n.原子Australia n.澳大利亚Austria n.奥地利autumnal equinox n.秋分axis n.轴;地轴Azores high n.亚速尔高压BBaikal n.贝加尔湖balance n.平衡Balkan Peninsula adj.巴尔干半岛Baltic Sea n.波罗的海Bangladesh n.孟加拉国barchan n.新月形沙丘basaltic adj.玄武岩的basin n.盆地bayou/estuary n.河口bed width n.河床宽度Berlin n.柏林Biosphere n.生物圈biotic adj.生物的birth rate n.出生率births n.出生Black Sea n.黑海bluffs n.悬崖Bombay n.孟买Brazil n.巴西Brazilian Highlands n.巴西高原breast feeding n.哺乳喂养Brisilia n.巴西利亚Bruno n.布鲁诺buckling and faulting n.弯曲和断层Buddha n.佛Buddhism n.佛教Bulgaria n.保加利亚Burma n.缅甸CCalcutta n.加尔各答Cambodia n.柬埔寨Canberra n.堪培拉canyon n.峡谷Cape of Good Hope n.好望角carbon dioxide n.二氧化碳carbon monoxide n.一氧化碳Caribbean Sea n.加勒比海carnivores n.食肉动物cash farming n.商品农业Caspian Sea n.里海cattle n.牲畜cattle ranching n.牧牛Caucasus Range n.大高加索山脉celestial body n.天体changes in daylight and darkness n.晨昏交替Chicago n.芝加哥Christianity n.基督教chromosphere n.色球circle of illumination n.晨昏线cirques, aretes, horns and U-shaped valleys n.冰斗、刃岭、角峰和U 形山谷clearing showers n.晴朗阵雨climate n.气候clockwise n.顺时针coast n.海岸coastal plain n.滨海平原coastal zone n.海岸带coastline n.海岸线cold current n.寒流cold front n.冷锋cold wave n.寒潮combustion n.燃烧comet n.彗星commerce n.商业中心commercial center n.国际贸易commercial route n.商业通道communication and transportation n.交通运输commuters n.通勤者competition n.竞争components of population changen.人口组成的变化comprise v.包含；构成concentration n.集中condensation n.凝结condensation and lapse rates n . 凝结作用和递减率conduction n.传导conflict vi.冲突;争执congested adj.拥挤的coniferous adj.松柏科的；针叶科的continental adj.大陆性的continental crust n.大陆地壳continental drift n.大陆飘移continental shelf n.大陆架continuous adj.连续的controls on weathering n.控制风化作用convection n.对流convergence n.辐合cooperation n.合作Copernicus n.哥白尼core n.地核Coriolis force n.科氏力counterclockwise n.逆时针counter-urbanization n.逆城市化Croatia n.克罗地亚crude birth rate n.自然出生率crude death rate n.自然死亡率crust n.地壳crystal shape n.晶体crystals n.水晶cultivated land n.耕地cumulonimbus n.积雨云current n.水流;气流cut-off n.截断cyclone n.气旋cyclonic adj.气旋的cyclonic disturbances n.气旋的扰动Czech n.捷克人Ddairy farming n. 乳畜业dam n.大坝Danube n.多瑙河daytime sea breeze n.日间海风De revolutionibus orbium coelestium n.天体运行论Dead Sea n.死海Deccan plateau n.德干高原decomposer n.分解者deforestation n.森林砍伐degrading n.降低deindustrialization n.后工业化deity n.神,神性delta n.三角洲delta plain n.三角洲平原density n.密度deposition n.沉积depression n.低气压depression n.凹陷;凹陷处depression belt n.低压带descending plate n.下降板块destruction of the tropical rainforest n.热带雨林的破坏detritivores n.食腐动物, 食碎屑者developing world city n.发展中的世界城市dew-point n.露点diameter n.直径differentiate vt.区分direct solar radiation n.太阳直射disastrous n.灾难性的discharge n.流量discontinuous adj.不连续的distribution of arid and semi-arid environment n.干旱和半干旱环境的分布divergence n.辐散.diverse adj.不同的diversified adj.多样化的diversity n.多样性dolomite n.白云石downpour n.倾盆大雨downwind adj.顺风的drift n.漂流droplet n.小滴dry-hot wind n.干热风dune n.沙丘dwellings n.居住Eearth n.地球earth revolution n.地球公转earth rotation n.地球自转earthquake n.地震earth's axis n.地轴East Asia n.东亚ebb n.退潮ecliptic plane / earth's orbit plane n.黄道ecological service n.生态服务economic increase n.经济增长economy n.经济ecosystem n.生态系统effect of friction n.摩檫力作用Egypt n.埃及electromagnetic wave n.电磁波element n.要素elevation n.海拔ellipse n.椭圆England n.英国environment n. 环境environmental issue n.环境污染environmental logo n.环境标志environmental pollution n.生态破坏environmental protection n.环境保护equator n.赤道equatorial low n.赤道低压equatorial though n.赤道低压槽equinox n.春分;秋分erosion n.侵蚀establish vt.建立Ethiopia n.埃塞俄比亚Ethiopian adj.埃塞俄比亚的Euphrates n.幼发拉底河Eurasian adj.欧亚(大陆)的European Union(EU) n.欧洲联盟evaporation n.蒸发evergreen adj.长绿的Everest n.珠穆朗玛峰exchange of energy between earth and atmosphere n.地球和大气层之间的能量的交换exclusive economic zone n.专属经济区exploit vt.开采开发extensive farming n.粗放农业extinct adj.以熄灭的extragalactic system n.河外星系Ffactors of agricultural location n.农业区位因素factors of industrial location n.工业区位因素factors of urban location n.城市区位因素farming outputs n.农业产出farming inputs n.农业投入fault n.断层fertile adj.肥沃的fertility n.肥力；出生率financial center n.金融中心first quarter moon n.上弦月fish farming n.渔业fishing ground n.渔场flatten v.变平float vi.漂浮floodplain n.泛滥平原fog n.雾fohn effect n.焚风作用fohn winds n.焚风fold n.褶皱fold mountains n.褶皱山地formation of precipitation n.降水的形成formulate vt. 规划;设计fossil n.化石France n.法国freeze-thaw n.冻融；冻土－解冻frigid zone n.寒带front n.锋frontal surface n.锋面frontal rain n.锋面雨frost n.霜冻frozen soil n.冻土Fuji-san n.富士山full moon n.满月；望月fumes n.烟雾fungi n.真菌GGalaxy n.银河系gale n.狂风Galileo n.伽利略Ganges n.恒河gaseous adj.气体的general atmospheric circulation n.大气环流geological processes n.地质作用geological disaster n.地质灾害geological time n.地质时期geomorphy n.地貌geostrophic wind n.地转风Germany n.德国glacial age n.冰期glacial deposition n.冰川沉积glacial erosion n.冰川侵蚀glaciate vt. 使结冰;以冰覆盖glaciation n.冰川作用glacier n.冰川global circulation models n.全球环流模式global warming n. 全球变暖gobi n.戈壁gorge n.峡谷gradient n.坡度gradient wind n.梯度风granular n.粒状Great Rift Valley n.大裂谷Greece n.希腊Green revolution n.绿色革命greenhouse effect n.大气保温效应greenhouse effect n.温室效应Greenland n.格陵兰岛Greenwich Observatory n.格林尼治天文台Gross National Product （GNP）n.国民生产总值gulf n.海湾Gulf of Genoa n.热那亚湾Gulf of Mexico n.墨西哥湾gutters n.排水沟Hhandicraft industry n.手工业harmonize v.使协调一致heliocentric theory n.日心说helmet n.头盔hemisphere n.半球herbivores n.食草动物hierarchy n.等级high pressure n.高压highway transportation n.公路运输Himalayas n.喜马拉雅山脉Hokkaido n.北海道岛hollow adj.空的horizontal n.地平线housing problem n.住房问题how winds are steered in the upper atmosphere n.在大气上层风是怎样进行human and economic factors n.人文及经济因素humidity n.湿度humification n.腐殖化hurricane n.飓风hydroelectric adj.水力电气的hydroelectric power plant n.水力发电站hydrosphere n.（地）水圈……………………………………IIce sheet n.（地）大冰原；冰盾；冰盖immigration n.迁进；外来居民impact n.影响increase v.增加Indian n.印度Indochina Peninsula n.中南半岛Indonesia n. 印度尼西亚Indus River n.印度河industrial concentration n.工业集聚industrial dispersion n.工业分散industrial location n.工业区位industrialization n.工业化industry n.工业infant n.婴儿infertile adj.不肥沃的innovation n.革新input-output system n.投入－产出系统intensive farming n.集约农业intermittent showers n.阵international adj.国际的international trade n.金融中心internet n.商业intervene vi.介乎于…其间ionosphere n.电离层Iran n.伊朗Iraq n.伊拉克irrigation n.灌溉；冲洗Islam n.伊斯兰教island arcs n.岛弧Island Shikoku n.四国岛isobar n.等压线isotherms n.等温线Israel n.以色列Italy n.意大利JJapan n.日本Java n.爪哇岛Jerusalem n.耶路撒冷Jordan n.约旦Judaism n. 犹太教Jupiter n.木星Jurassic adj.侏罗纪的，侏罗系的KKarst n.喀斯特地貌katabatic wind n.下降气流风Kenya n.肯尼亚Kepler n.开普勒Kilimanjaro n.乞力马扎罗山Kobe n.神户Kuwait n.科威特Kyushu n.九州岛Llabour n.劳动力lag time n.延迟时间lagoon n.泻湖Lake Erie n.伊利湖Lake Huron n.休伦湖Lake Michigan n.密歇根湖Lake Ontario n.安大略湖Lake Superior n.苏比利尔湖land n.土地land and ocean changes n.海陆变迁land and sea breezes n.陆地和海洋的微风land and water distribution n.海陆分布land degradation and desertification n.土地退化和沙漠化landform n.地形landforms produced by glacial erosion n.冰川侵蚀形成的地形landmark n.陆标;地界标landslide n.滑坡Laos n.老挝Latin America n.拉丁美洲latitude n.纬度layer n.层；圈层leeward n.下风Liechtenstein adj.列支敦士登的light-year n.光年limestone n.石灰石linear speed n.线速度lithosphere n.（地）岩石圈，地壳local wind n.区域风；局地风location n.区位logging n.伐木London n.伦敦Longitude n.经度Los Angeles n.洛杉矶low pressure n.低压low-latitude (tropical)weather systems n.低纬度（热带）天气系统low-lying adj.低的lunar year n.农历Mmacula n.太阳黑子Madagascar n.马达加斯加岛magma rock n.岩浆岩magnetic field n.磁场magnetic storm n.磁暴main factors and processes affecting population size and distribution n.影响人口大小和分布的主要因素和过程mainland n.大陆maintain v.维持;建立；majority n.大多数;过半数Makkah n.麦加Malay Archipelago n.马来群岛Malaysia n.马来西亚man-earth relationship n.人地关系manned spaceship n.载人飞船mantle n.地幔Mariana Trench n.马里亚纳海沟marine adj.海的；海中的maritime n.海洋maritime climate n.海洋性气候market n.市场Mars n.火星marsh n.沼泽massive adj.巨大的;大块的mean density n.平均密度meanders n.曲流mediterranean adj.地中海的Mediterranean Sea n.地中海Mediterranean zone n.地中海带Mekong River n.湄公河meltwater n.融雪水Mercury n.水星meridian n.经线mesa n.台地mesosphere n.散逸层、中间层metagalaxy n.总星系；宇宙metamorphic rock n.变质岩metamorphism n.变质作用meteoroid n.流星体midday n.正午middle and high latitudes n.中、高纬度Middle Asia n.中亚Middle East n.中东mid-latitude cyclonic belt n.中纬度气旋带mid-latitude weather systems n.中纬度的天气系统midnight n.午夜migration n.迁移military adj.军事的;军用的mineral n.矿物Mississippi n.密西西比河mixed farming n.混合农业mode of transport n.运输方式modern agriculture n.现代农业Moho n.莫霍面molecules n.分子monogamy n.一夫一妻制monsoon n.季风;雨季moraines n.冰碛morphology of the urban heat island n.城市热岛地形mortality n.死亡率………………………………Moscow n.莫斯科moss n.苔,藓mountain and valley winds n.山地和山谷风mountaineering n.登山mud-rock flow n.泥石流Nnationality n.民族natural resource n.自然资源natural zone n.自然带navigate v.航行;航海nebula n.星云needle leaves n.针叶Neptune n.海王星Netherlands n.荷兰New Delhi n.新德里new moon n.朔月new towns and green belts n.新城镇和绿带New York n.纽约newly rising industry n.新兴工业Nigeria n.尼日利亚Nile n.尼罗河nitrogen n.氮Noah's Ark n.诺亚方舟nocturnal land breeze n.夜间陆地风noise pollution n.噪声污染nomadism n.游牧non-commercial adj.非商业的North Asia n.北亚North Pole n.北极north-east monsoon n.东北季风Norway n.挪威noxious adj.有害的nuclear adj. (核)核子的;原子能的nuclear fusion reaction n.核聚变Ooasis n.绿洲Ob n. 鄂毕河oblate adj.（数）椭圆的；扁圆的；oblique adj.斜的occluded front n.锢囚锋occupy v.占据;占有ocean current n.洋流ocean ridges n.洋脊omnivores n.杂食动物optimum population n.最佳人口orbit n.(天体等)运行轨道organic substance n.有机物organism n.生物organization n.组织origin n.起源Osaka n.大阪outer core n.外地核out-migration n.迁出outwash n.冲刷overpopulation n.人口过剩overtaking v.超越ownership n.所有权;物主身份ox-bow lake n.牛轭湖oxygen n.氧ozone n.臭氧ozonosphere n.臭氧层Ppaddy field n.水田Pakistan n.巴基斯坦Pamirs n.帕米尔高原Pampas n.南美大草原，潘帕斯草原Panama Canal n.巴拿马运河parallel n.纬线Paris n.巴黎pastoral farming n.畜牧业pasture n.牧场penguin n.企鹅peninsula n.半岛perihelion n.对流层顶periods of growth n.增长的周期perpendicular adj.垂直的Persian adj.波斯的,波斯人Persian Gulf n.波斯湾Persist n.持续Pesticide n.杀虫剂phases of the moon n.月相photochemical adj.光化学的Photosphere n.日冕photosynthesis n.光合作用phreatic water n. 潜水；地下水physical factors n.自然因素pigment n.色素pipeline transport n.航空运输plain n.平原Planalto do Brasil n.巴西高原planet n.行星plantations n.种植plants n.植物plate n.板块plate tectonic theory n.板块构造学说plate tectonics n.板块构造plateau n.高原Pluto n.冥王星polar circle n.极圈polar continental adj.极地大陆的polar high n.极地高压polar maritime adj.极地海洋的（mp）polar night n.极昼Polar Plat n.南极高原polar region n.极区；极地pollutant n.污染物pollution n.污染pond as an ecosystem n.作为一个生态系统的水塘pools and riffles n.池沼和浅滩population density n.人口密度population distribution and change n.人口分布和变化population explosion n.人口爆炸population growth n.人口增长population policy n.人口政策population pressure n.人口压力population size and distribution factors n.人口大小和分布populous adj.人口密集的port n.港口precipitation n.降水量;雨量precipitation patterns n.降水类型pressure gradient n.气压梯度pressure low n.低（气）压pressure high n.高（气）压pressure-gradient force n.压力梯度力prevailing wind n.盛行风prime meridian n.本初子午线primitive farming n.原始农业prisere n.演替productivity n.生产力promote v.提升protection n.保护Pyramid n.金字塔Qquality n.质量Rrace n.种族radiation and sunshine n.辐射和日照railway transportation n.铁路运输rainforest n.热带雨林rainstorm n.暴风雨raw materials n.原料ray n.射线;光线reclamation n.开垦Red Sea n.红海relationship n.关系religion n.宗教residential area n.居住区resource n.资源revolution n.绕转;旋转;旋转一周revolution cycle n.公转周期Rhine n.莱茵河rice farming n.水稻种植业ridge v.使成脊；使降起riffle n.浅滩rill n.小溪Rio de Janerio n.里约热内卢river channel n.河道river's load n.河流搬运rock n.岩石Rocky Mountains n.落基山脉Roma n.罗马Romania n.罗马尼亚rotation n.旋转;旋转一周rotation cycle n.自周期Rotterdam n.鹿特丹runoff n.径流rural area n.乡村Rural Settlement n.乡村聚落Russia n.俄罗斯SSahara n.撒哈拉Sahara Desert n.撒哈拉沙漠Saint Petersburg n.圣彼得堡salinity n.盐分;盐度San Francisco n.圣弗朗西斯科（旧金山）sand dunes in hot deserts n.热沙漠的沙丘sandstorm n.沙尘暴satellite n.卫星satellite town n.卫星城saturated vapour pressure n.饱和蒸汽压Saturn n.土星Saudi Arabia n.沙特阿拉伯Savannas n.热带稀树草原Scandinavia n.斯堪的纳维亚scary n.断崖scattered adj.分散的scrub n.灌木林seal n.海豹sea-level n.海平面seaport n.海港;港口都市seasonal variation in river flow :the regime n.河流季节变化：变律sediment rock n.沉积岩sedimentary deposit n.沉积物sedimentation n.沉积作用seismic adj.地震的semitropical adj.副热带的;亚热带的settlement n.聚落shallow beach n.浅滩shell n.壳side beach n.边滩sidereal day n.恒星日sidereal year n.恒星年signatory n.签约国silted up n.淤积sima n.硅镁层Singapore n.新加坡site n.地点situation n.位置sleet shower n.降雨雪Slovakia n.斯洛伐克slums n.贫民区socio-economic determinants n.社会－经济的决定因素soil n.土壤soil erosion n.水土流失soil profile n.土壤剖面solar activity n.太阳活动solar altitude n.太阳高度Solar Constant n.太阳常数solar day n.太阳日solar energy n.太阳能solar flare n.耀斑solar radiation n.太阳辐射solar system n.太阳系solid shape n.固态solid inner core n.固体内核solstice n.至日；至点South Asia n.南亚South Pole n.（地）南极Southeast Asia n.东南亚south-west monsoon n.西南季风space explorer n.空间探测器space shuttle n.航天飞机space station n.航天站sparse adj.稀少的sparsely adv.稀疏的,稀少的species n.种;类spin v.快速旋转;回旋split v.分开,分离spring equinox n.春分star n.恒星stature n.身材steppe n.干草原strait n.地峡;海峡Strait of Gibraltar n.直布罗陀海峡Strait of Malacca n.马六甲海峡stratosphere n.平流层；同温层…………………………………………structure of the air above the urban area n.城市地区上空空气的结构subduction n.俯冲作用subpolar low n.副极地低压sub-Saharan Africa n.撒哈拉以南的非洲subsiding n.下沉subsistence agriculture n.自给农业subsolar point n.太阳直射点subtropical high n.副热带高压sub-tropical highs n.亚热带高气压succession n.演替Suez Canal n.苏伊士运河Sumatra n.苏门答腊岛summer solstice n.夏至summit n.顶点sun n.太阳sunlight hours n.日照小时sunlit adj.太阳照射的superenergy electronic particles n.高能带电粒子sustainable development n.可持续发展Sweden n.瑞典Switzerland n.瑞士Sydney n.悉尼Ttall grasses n.高草Tasmania n.塔斯马尼亚岛tectonic plate n.地壳构造板块Tectonic plate dirft n.板块漂移telescope n.天文望远镜temperate coniferous forest n.温带针叶林temperate deciduous broadleaf forest n.温带落叶阔叶林temperate deciduous woodland n.温带落叶林地temperate grasslands (steppe) n.温带草原（干草原)temperate zone n.温带temperature n.温度Tethys n.古地中海,特提斯海Thailand n.泰国the effect of city morphology on radiation received at the surface n.城市地貌对地表接受辐射的影响theories of plate motions and oceans ridges n.板块运动和大洋中脊理论thermal n.热的thermosphere n.热成层；电离层third quarter moon n.下弦月Three Gorges Dam n.三峡大坝thunder n.雷thunderstorms n.雷暴雨Tibet Plateau n.青藏高原tidal size n.潮汐大小tide and the tidal cycle n.潮汐和潮周期Tigris n.底格里斯河till n.冰碛物time zone n.时区Tokyo n.东京torrents n.山洪total fertility rate n.总的出生率trade-wind n.信风traditional farming n.传统农业traffic problems n.交通问题transitional adj.过渡的transport n.交通运输transport line n.管道运输transport junction /transport network n.交通运输网transportation n.运输transportation artery n.运输要道treatment n.处置,处理;治疗treaty n.条约;谈判trench n.海沟tributary n.支流trophic pyramid n. 营养（食物）金字塔tropic n.回归线Tropic of Cancer n.北回归线Tropic of Capricorn n.南回归线tropic zone n.热带tropical continental adj.热带大陆的tropical cyclone n.旋风;飓风;气旋；热带气旋tropical disturbances n.热带扰动tropical maritime adj.热带海洋的tropical rainforest n.热带雨林tropical semi-arid n.热带的半干旱tropical year n.回归年tropicalplant n.热带植物troposphere n.对流层tundra n.(北极地区的)冻原;苔原tundra belt n.苔原带turbulence n.湍流Turkey Strait n.土耳其海峡typhoon n.(气)台风UUkraine n.乌克兰ultraviolet ray n.紫外线underlying surface n.下垫面underneath n.在…下面undernourished adj.营养不良的underpopulation n.人口不足United Nations n.联合国United States n.美国uplift n.上升upper mantle n.上地幔upstream n.上游Ural Mountains n.乌拉尔山Uranus n.天王星urban heat island n.城市热岛urban microclimates n.城市小气候urban planning n.城市规划urban problems n.城市问题urban road network n.城市道路网urban settlement n.城市聚落urbanization n.城市化urban-rural shift n.城市－乡村迁移utilization n.利用Vvaried adj.多变的vegetation n.植物vegetation cover n.植被覆盖Venus n.金星vernal adj.春天的vertical stratification n.垂直的分层vessel n.血管;脉管Vienna n.维也纳Vietnam n.越南views of population growth n.人口增长观点vigorous adj.有力的Vladivostok n.夫拉迪乌克托克volcano n.火山Volga n.伏尔加河volume n.体积Wwarm current n.暖流warm front n.暖锋warm front approaches n.暖锋临近warm sector n.暖区Washington n.华盛顿wash-load n.冲积物water circulation n.水循环water level n.水位water source n.水资源water vapor n.水蒸汽waterfall n.瀑布waterway n.排水道waves and tides n.波浪和潮汐weapon n.武器weather n.天气weather associated with a depression n.与低压有关的天气weather forecast n.天气预报weather system n.天气系统weathering n.风化作用West Asia n.西亚West Siberian Plain n.西西伯利亚高原westerlies n.西风带wet and dry tropics n.湿润的和干燥的热带whale n.鲸;捕鲸wind v.弯曲windward adj.上风的，迎风的winter n.冬天winter solstice n.冬至world distribution n.世界分布World Trade Organization n.世界贸易组织XX ray n. X射线xerophytes n.旱生植物Yγ ray n. γ射线Ztimezone n.区时。

fdtd圆偏光的透射率The problem at hand is to determine the transmittance of circularly polarized light through a finite-difference time-domain (FDTD) simulation. This requires an understanding of FDTD techniques, circular polarization, and the factors influencing transmittance.FDTD is a numerical method used to solve Maxwell's equations in both time and space domains. It discretizes the electromagnetic field into a grid and updates the field values at each time step based on the finite differences between neighboring points. By simulating the behavior of electromagnetic waves in a given structure, FDTD can provide valuable insights into their propagation and interaction.Circular polarization refers to the polarization state of light where the electric field vector rotates in a circular pattern as the wave propagates. It is characterized by two components, the right-handed circularpolarization (RCP) and the left-handed circularpolarization (LCP). These components have equal amplitude but rotate in opposite directions.To determine the transmittance of circularly polarized light, we need to consider the properties of the medium through which the light is passing. The transmittance is influenced by factors such as the refractive index of the medium, the angle of incidence, and the polarization state of the incident light. Additionally, the thickness and geometry of the medium can also affect the transmittance.In the FDTD simulation, we would set up a computational domain that includes the medium of interest. The incident circularly polarized light would be introduced at aspecific angle of incidence and propagated through the medium. The simulation would track the electric and magnetic fields at each point in the grid, allowing us to analyze the behavior of the light as it interacts with the medium.By analyzing the field values at the output side of themedium, we can calculate the transmittance of thecircularly polarized light. This can be done by comparingthe amplitude and phase of the RCP and LCP componentsbefore and after the medium. The transmittance is then defined as the ratio of the output power to the input power.In conclusion, determining the transmittance ofcircularly polarized light through an FDTD simulation involves understanding FDTD techniques, circular polarization, and the factors influencing transmittance. By setting up the simulation correctly and analyzing the field values, we can calculate the transmittance and gaininsights into the behavior of circularly polarized light in different media.。