电气工程专业英语ppt课件

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电气工程专业英语课件lecture3-2012

电气工程专业英语课件lecture3-2012
7
Lecture 3
Other considerations for an overhead line include: the number, size, and spacing of conductors per-phase bundle; the phase to phase spacing; the number, location, and conductor type for overhead neutrals concerning with lightning shielding; the level of insulation; ect. The design of a power line depends upon the following criteria: i) The amount of active power it has to transmit. ii) The distance over which the power must be carried. iii) The cost of the power line. iv) Esthetic considerations, urban congestion, ease of installation, and expected load growth.
Lecture 3
1. As the system expands and higher voltage levels become necessary for transmission, the older transmission lines are often relegated to subtransmission function. 随着系统的扩大和更高的电压等级为输电所必需, 随着系统的扩大和更高的电压等级为输电所必需,旧 的输电线路往往被移交给中压输电功能。 的输电线路往往被移交给中压输电功能。 New Words and Expressions backbone 中枢 integrated 综合的,完整的 综合的, voltage level 电压等级 step up 升压 step down 降压 subtransmission 中压输电,次输电 中压输电, subsystem 子系统 bulk 大量的 demarcation 划分 relegate to 委托给,移交给 委托给, overhead line 架空线 cable 电缆

电气专业英语基础 ppt课件

电气专业英语基础  ppt课件

ppt课件
8
常用的前缀和后缀却多达百个,可见派生法的构词 能力是非常强的。作为一个专业技术人员,至少应掌 握50个常用前缀和后缀。
前缀(prefix):词义变化,词类不变 后缀(suffix):词义可能变化可能不变,词 类一定会变
ppt课件
9
名词前缀
前缀 auto-
含义 自动,自己,自身
counterhydr(o)
专业或技术词汇 某个专业所特有的词汇,其专业性强,词义狭窄和单一。
diode ,
(二极管)
capacitor ,
(电容器)
substation ,
(变电站,变电所)
autotransformer,(自耦变压器)
superconductivity (超导特性)。
ppt课件
4
次技术词汇
很多专业和学科所共有的词汇,不同专业和学 科往往具有不同词义 power : 幂,乘方 动力,功率,效率
名词+形容词(n+adj.) →adj.: ice-cold, network-wide 名词+副词(n+adv.)→n.,adj.: feedback
形容词+名词(adj+n)→n.,adj.:
low-pass, high-speed, short-circuit, newtype
形容词+名词+ed (adj.+n.+ed)→adj.:
隶属于科技英语 是科技英语的一部分,以表达科技概念、理论与事实为主要 目的。遵守科技英语的语法体系和翻译方法;特别注重客观事实和真理,表达准 确、精练和正式。
是结合各自专业的科技英语 有很强的专业性,涉及的面更加狭窄,与专业内 容配合更为密切。

7-4 Distance Protection 电气工程及其自动化专业英语课件(共29张PPT)

7-4 Distance Protection 电气工程及其自动化专业英语课件(共29张PPT)
The operation of distance protection depends on the basic fact that on the occurrence of a fault, the distance between any point in the power system and
第六页,共29页。
Section 4 Distance Protection
(ii) Errors in the relay, (iii) Errors in the current transformers (CTs) and voltage transformers (VTs), (iv) Errors in the data on which the impedance settings are made.
第四页,共29页。
Section 4 Distance Protection
discriminative tripping of the circuit breakers controlling the various feeders can be obtained. Usually, a 3-zone distance protection schemes is employed for transmission line protection.
第八页,共29页。
Section 4 Distance Protection
In many cases, where the consecutive line sections differ very much in length, alterations in the above scheme, in the number of steps or time delays, may be necessary to give optimum selectivity and protection.

电气工程专业英语课件lecture11-2012

电气工程专业英语课件lecture11-2012
4
Lecture 11
No network of DC lines is possible at this time because no circuit breaker is available for direct current comparable to the highly developed AC breakers. The AC breaker can extinguish the arc which is formed when the breaker opens because zero current occurs twice in each cycle. The direction and amount of power in the DC line is controlled by the converters in which grid-controlled mercury-arc devices are being displaced by the semiconductor devices. 1. Unlike overhead lines, underground cable is invisible, free from atmospheric pollution, and solves the problem of securing rights of way. 和架空线不同,地下电缆是看不见的,免受大气污染,并解 决了安全的公用通道问题。
5
Hale Waihona Puke Lecture 112. DC transmission remains very limited in usage except for long lines because there is no DC device which can provide the excellent switching operations and protection of the AC circuit devices. 直流输电除用于长线(输电)以外在应用上仍然十分有限, 这是因为没有直流设备能够提供交流装置所具有的卓越的开 关操作和保护功能。 3. The direction and amount of power in the DC line is controlled by the converters in which grid-controlled mercury-arc devices are being displaced by the semiconductor devices. 直流线路上功率的流向和数量用换流器控制,其中栅控汞弧设 备正在被半导体装置取代。

电气工程及其自动化专业英语ppt课件

电气工程及其自动化专业英语ppt课件

seen, increase of current from zero to
I≈I1 causes the terminal voltage of the source to decrease linearly
V12=V=E-VS=E-RSI
Fig.1.3
In other words, the voltage drop VS across the source resistance rises in proportion to the current. This goes on until
电气工程及其自动化专业英语
Specialized English for Electrical Engineering & Its Automation 戴文进 主 编 杨植新 副主编
1
Contents
• Part 1 Electrics and Electronics • Part 2 Electric Machinery • Part 3 Electrical Engineering • Part 4 Modern Computer Control
• When a load is connected to the source terminals (the circuit is then said to be loaded) and the circuit is closed, a current begins to flow round it. Now the voltage between source terminals 1 and 2 (called the terminal voltage) is not equal to its e.m.f. because of the voltage drop VS inside the source, that is, across the source resistance RS VS=RSI

最新电气工程专业英语实用教程-1(共21张PPT)精品课件

最新电气工程专业英语实用教程-1(共21张PPT)精品课件
接得到的电阻是1/(1/10+1/22+1/47)=5.997欧姆。
第十四页,共二十一页。
参考 译文 (cānkǎo)
2.电阻和功率 下面讨论电阻器的功率性能。在电炉灶面、烤箱、电暖炉、 电水壶和烘箱上设置电阻器,其目的是利用它处理和消耗很大的 功率。这些电器都是根据某些物质的这一功率性能而制成。 从欧姆定理(dìnglǐ)我们知道:P=I*I*R,即功率等于电流的平 方乘以电阻。上面例子中,三个电阻器串联得到79欧姆电阻器, 如果在它们上面加上24伏特电压,从欧姆定理就可知流过的总电 流:I=V/R=24/79=0.304安培。 用任何功率公式我们都可以确定0.304安培的电流流过79欧 姆的电阻总共要消耗7.3瓦特的能量!而且,当电阻器上的电阻大 小不等时,电阻越大,消耗的能量也就越多。
第七页,共二十一页。
Notes
[2] Resistors which are deliberately designed to handle and radiate large amounts of power are electric cooktops, ovens, radiators, electric jugs and toasters. 本句的主语是Resistors,定语从句“which are deliberately designed to handle and radiate large amounts of power”修饰Resistors。在该定语从句中,to
handle and radiate large amounts of power是一个动词不定式短语,做目的 (mùdì)状语,修饰谓语are designed。
第八页,共二十一页。
Notes

电气工程专业英语课件lecture8-2012

电气工程专业英语课件lecture8-2012

Lecture 8
1. Power system stability may be broadly defined as that property of a power system that enables it to remain in a state of operating equilibrium under normal operating conditions and to regain an acceptable state of equilibrium after being subjected to a disturbance. 电力系统稳定性可以广泛定义为电力系统的一个特性,即 在正常工作条件下保持运行平衡状态,在受到干扰以后可 以重新回到可接受的平衡状态。 2. Since power system rely on synchronous machines for generation of electrical power, a necessary condition for satisfactory system operation is that all synchronous machines remain in synchronism or, colloquially, “in step”. 既然电力系统依靠同步电机发电,系统正常运行的一个必 要条件是所有的同步电机保持同步,通俗一点讲就是“步 调一致”。 6
Lecture 8
New Words and Expressions equilibrium 平衡,均衡 disturbance 干扰,扰动 manifest 表现 colloquially 用通俗语 collapse 崩溃 surviving 幸免于 actuate 激励,驱使

电气工程及其自动化专业英语通用课件

电气工程及其自动化专业英语通用课件
and Expression • Professional English Literature
Reading and Translation • Academic paper writing
guidance
01
Basic knowledge of electrical engineering
Definition of Electrical Engineering
Academic Paper Writing Standards
How to write professional English papers
THANK YOU
Robot
A machine that can sense, think, and act, commonly designed to perform tasks automatically
Sensors
Devices that measure physical properties such as temperature, pressure, or light intensity
General English Courseware for Electrical Engineer
• Basic knowledge of electrical engineering
• Fundamentals of Automation • Professional English Vocabulary
Electrical engineers are responsible for the design, development, and operation of electrical systems in various industries, including power generation, manufacturing, transportation, and telecommunications They also work in research and development, teaching, and consulting

电气工程及其自动化专业英语第一单元课件

电气工程及其自动化专业英语第一单元课件

AC and DC electricity
AC (Alternating Current): The flow of electricity in which the direction of current changes periodically.
DC (Direct Current): The flow of electricity in which the direction of current remains constant.
02
Basic knowledge of electrical engineering
Basic concepts of circuits
Circuit
A closed path that allows current to flow.
Series and parallel circuits
Series circuits have current flow in the same direction, while parallel circuits have current flow in opposite directions.
Over time, Electrical Engineering and Automation has evolved to include a wide range of sub-fields, including power engineering, control systems, robotics, and more.
Computer control systems can be used for a wide range of applications, including industrial manufacturing, process control, aviation, and more.

电气工程专业-英语PPT优质课件

电气工程专业-英语PPT优质课件
.
2.1 Grammar Features
3) The device includes an instrument transformation and a relay system which has two circuits in it.
The device includes an instrument transformation and a relay system with two circuits in it.
.
2.1 Grammar Features
③ 不定式
用不定式短语来替代表示目的和功能的从句或语句 (1) The capacity of individual generators is larger and larger so that the increasing demand of electric power is satisfied. The capacity of individual generators is larger and larger to satisfy the increasing demand of electric power.
专业英语(English for Special Science and Technology)
隶属于科技英语 是科技英语的一部分,以表达科技概念、理论与事实为主要 目的。遵守科技英语的语法体系和翻译方法;特别注重客观事实和真理,表达准 确、精练和正式。
是结合各自专业的科技英语 有很强的专业性,涉及的面更加狭窄,与专业内 容配合更为密切。
(3) 省略句使用频繁 (精炼) 省略成分:状语从句中的主语、全部或部分谓语;定语从句中的关系代词 which和that、从句中的助词等;还常用介词短语替代从句。

电气工程专业英语unt1PPT课件

电气工程专业英语unt1PPT课件

A loop is any closed path in a circuit. A loop is a closed path formed by starting at a node, passing through a set of nodes, and returning to the starting node without passing through any node more than once①.
voltage across them②. The 5Ω and 2Ω resistors are
The 2Ω resistor, the 3Ω resistor, and the current source are in parallel because they are connected to the same two nodes (b and c) and consequently have the same
b的3个点".此句可译为:注意到形成节点b的3个点是通过理
想导线相连接的,因此组成了1个节点.
.
8
1.1 Introduction to Circuit Theory text
The same is true of ①the four points forming node c.
We demonstrate that (证明 )the circuit in Fig.1.1 has only three nodes by redrawing the circuit in Fig.1.2.
6
1.1 Introduction to Circuit Theory text
In network topology, we study the properties relating to (关于...的特性)the placement of elements in the network and the geometric configuration of the network. Such elements include branches, nodes, and loops.

电气工程与自动化专业英语PPT课件2-1

电气工程与自动化专业英语PPT课件2-1

Section 1 Introduction
control the furnace. When the room temperature drops below a preset value, the thermostat switch closes turning on the furnace. Once the room temperature rises high enough, the switch opens turning off the furnace. The current through the switch provides a digital representation of the temperature variation: ON equals "too cold" while OFF equals "notion 1 Introduction
Fig.2-2 Components of a signal system
Section 1 Introduction
Many electrical signals derived from physical systems are obtained from devices called transducers. We have already encountered an example of an analog transducer, the thermocouple pair. It converts temperature difference (the physical variable) to a voltage (the electrical variable). Generally, a transducer is a device that converts a physical or mechanical variable to an equivalent voltage or current signal. Unlike the thermocouple example, however, most transducers require some form of electrical excitation to operate.

《电气工程及其自动化专业英语》课件第六节(与“电压”相关文档)共12张PPT

《电气工程及其自动化专业英语》课件第六节(与“电压”相关文档)共12张PPT
2. 利用电路方法(节点分析法、网孔分析法、叠加原 理等)解决问题 3. 把得到的相量转换成时域形式
第6页,共12页。
平衡三相电压
典型的三相系统由三个电源构成,这三个电压源通 过三根或四根导线(或输出线)与负载相连。三相系统 等效于三个单相电路。电压源可以连接成Y形如图1-23 (a)所示或连接成△形如图1-23(b)所示。
上式显示电压的幅度I 为而相位为φ+90,电压和电流 了它△决连定接了的与负电载源。相连的一台电动机的转动方向。
, 对流于过电电 感容 器器 L,的假电设流流为过:它的电流是
,电感器两端的电压是
复电制压音 Ua乐n,的U电b子n和电U路cn必分须别具介有于与a声线音与成中正线比n之的间电,压b和线电与流中。线n之m间以及c线与中线n之间,这些电压被称为相电压。
u t R t( t ) R I m c o s (t ) ( 1 2 3 )
此电压的相量形式为:

•• •
U m R Im R Im U R I( 1 2 4 )
第2页,共12页。
图1-17(b)显示在相量方面电阻器中电压——电流 之间的关系仍然反映欧姆定律,正如时域中一样。在方程 (1-24)中我们应当注意电压和电流之间的是关系相量 之间的关系,正如图1-18中的相量图所示。



U anU bnU cn(132)
由于三相电压彼此之间相位相差120度,所以 只有两种可能的组合。一种可能情况如图1-24(a) 所示而在数学上可表达为:

U an U p0

U bn U p 120

U cn U p240
第8页,共12页。
上式中Up是有效值。这种情况被称为abc次序或正序,

《电气工程专业英语》课件

《电气工程专业英语》课件
电流、电压、电阻
学习电气工程的基本概念,包括电流、电压和电阻的定义、计算方法和相关定律。
电路定律
研究欧姆定律、基尔霍夫定律和其他电路定律,理解电路中电流和电压的关系。
电路元件
介绍常见的电气元件,如电阻、电容和电感器件,并解释它们在电路中的作用。
电气设备与系统
发电机和变压器
输电与配电系统
学习发电机和变压器的工作原理, 以及它们在电力系统中的作用。
了解电力输送和配电系统的组成 部分,包括输电线路、变电站和 配电网络。
电气控制系统
探索电气控制系统的基本原理和 组件,包括电动机控制、自动化 和监控。
电气工程应用
1
电力系统
研究电力系统的设计、运行和管理,以及可再生能源和能源转换技术的应用。
2
电子设备与自动化控制
了解电子设备和自动化控制技术在电气工程中的应用,如PLC、SCADA和机器 人技术。
3
电气安全与维护
学习电气安全标准和维护要求,了解如何保护人员和设备的安全。
电气工程实践
实验室项目
通过实验室项目,将理论知识应用于实践,加深对电气工程原理和实验方法的理解。
工程案例分析
分析真实的电气工程案例,了解在实际项目中面临的挑战和解决方案。
职业规划和发展
提供关于电气工程职业发展的建议,包括就业前景、培训机会和职业道路。
《电气工程专业英语》 PPT课件
本课程旨在介绍电气工程的基础知识、电气设备与系统、电气工程应用以及 电气工程的实践,并提供职业规划和发展的建议。
课程介绍
通过本课程,您将了的应用。我们将深入探讨电气工程的 各个方面,帮助您建立坚实的基础。
电气工程基础知识
总结和展望
回顾本课程的主要内容,总结所学知识,并展望未来电气工程领域的发展和 趋势。

最新电气工程专业英语课件lecture1-教学文稿精品课件

最新电气工程专业英语课件lecture1-教学文稿精品课件
Part 2 Typical Topologies of Electric Power System
The equipments which form an electric system are arranged depending on the manner in which load grows in the area and may be rearranged from time to time.
电气工程专业英语课件lecture12012
第一页,共30页。
Introduction
学习专业英语的重要性 科研信息获取 专业英语阅读能力 技术情报资料 专业技术文献 工程(gōngchéng)设备文档资料 研究成果展示 专业英语写作能力 产品技术说明 学术论文发表 申请专利 国际交流合作 专业英语表达、听说、应变能力2
《电气工程及其自动化专业英语》 苏小林、顾雪平 主编. 北京:中国(zhōnɡ ɡuó)电力出版社,2008
《电力英语应用口语》 贾根娣、曹仁麟主编. 北京: 中国(zhōnɡ ɡuó)电力出版社,2002
6
第六页,共30页。
Lecture 1
Reading and Translation
Basic Concepts of Electric Power System
Transmission System and Transmission Lines
3
周周周周
2
Distribution System and Loads
4
Project-Stage of Erection and Acceptance
Relays and Protection Design
5

电气工程及其自动化专业英语.ppt

电气工程及其自动化专业英语.ppt
Machines • Unit 16 Three-Phase Induction (Asynchronous)
Machine with the Rotor at Standstill· • Unit 19 Armature Reaction of Salient-Pole
Synchronous Machine a Two-Reaction Theory
• Looked at another way, the leakage flux Φ 1 which links N1 turns alone and “leaks” between the two windings without linking the N2 turns, is a much smaller fraction of the total, making for(有助于, 倾向于) more efficient energy transfer.
Unit 11 The Transformer on No Load
• The Simple Two-Coil Transformer
The transformer is a straightforward application of Faraday's Law of Electromagnetic Induction. The simple transformer consists of two coils in close proximity. One coil of N1 turns is excited with alternating current and therefore establishes a flux φ11 which alternates with the current (随时间交变). The other coil is linked by (与---交链)most of this flux and thus has a mutually induced e.m.f. of value e2=-N2dφ21/dt.

《电气工程专业英语》课件

《电气工程专业英语》课件

02
Basic knowledge of electrical engineering
Circuit
A closed path that allows current to flow
Series Circuit
Circuit in which current flows through each component in sequence Voltage across each component is the same
Inductor
A passive two terminal electrical component that stores energy in a magnetic field when current passes through it
03
Power System and Power Generation
Importance
Power system is essential for meeting the energy needs of modern society
01
02
03
Thermal power generation
Burning fossil fuels (coal, oil, gas) to generate electricity
contents
目录
Electrical Engineering Practice and ApplicationVocabulary and Expression of Electrical Engineering English
01
Overview of Electrical Engineering

最新电气工程及其自动化专业英语第六单元课件精品课件

最新电气工程及其自动化专业英语第六单元课件精品课件

misoperation n. 误操作,误动作
第三页,共56页。
Notes
[1]. Electric power systems (or electric energy systems),
providing electricity to the modern society, have become indispensable components of the industrial world.
发动机的转速(zhuàn sù)不应超过最大允许 值。
➢This metal is not more useful than aluminium.
这种金属(jīnshǔ)不见得比铝更有用。
第十八页,共56页。
Translation of Negative Sentences
二、部分否定
(总括词‥‥not+谓语动词和其他)
译为:为现代社会供电的电力系统(或电能系统)已经成为这个工 业化世界(shìjiè)不可缺少的组成部分。
第四页,共56页。
Notes
[2]. The first complete electric power system (comprising a
generator, cable, fuse, meter, and loads) was built by Thomas Edison – the historic Pearl Street Station in New York City which began operation in September 1882.
部分否定是对叙述的内容做部分的,而不是全 部的否定。部分否定主要是由all, both ,every, each, often, always等词与否定词构成,相当于汉语“不 全是”、“不总是”、“并非都”、“未必都”、 “不是两个都”之意。这类否定句中的否定词not 有时和谓语在一起,构成谓语否定。形式上很像全 部否定,但实际上是部分否定,在翻译时要特别 (tèbié)注意。
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(2) 研究成果展示 专业英语写作能力
申报国家奖项 申请专利 发表学术论文:85%以上的科技资料都是以英语形式出版的
(3) 国际交流合作 专业英语表达、听说、应变能力
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1.3 课程的学习内容
主要内容:
基础知识(文体特点,语法特点,词汇特点,常用符号公式表达) 阅读翻译,专业词汇
周次
课时
安排
1
引言,语法特点,词汇特点
7
2.1 Grammar Features
(1) 广泛使用被动语态 (客观性)
主体多为客观的事物、现象和过程,在叙述推理过程中切忌加进作者 个人的主观臆断;
中心是客观现象及事物本身,而非动作的发出者,把论证说明的对象 置于句子主语的位置,既能突出中心,又能吸引读者的注意。 1) Electricity can be measured in amount and quality. 电可以用数量和质量来度量。
电能可以储存在被一绝缘介质隔开的两块金属板中,这样的装置被称为电容 器,它储存电能的能力就被称为电容。电容的测量单位是法拉。
9
2.1 Grammar Features
(2)广泛使用非谓语形式 (精炼)
非谓语动词在句子中可以起到名词,形容词或副词作用,动词的非谓语 形式分为动名词,分词,动词不定式。
8
高电压工程
5
9
Unit 4 Digital Circuit and Analog Circuit
10
数字电路和模拟电路
6
11
Unit 5 Electrical Machine
12
电机
13
论文写作:学习科技文献的写作格式及写作技巧
7
14
国际会议international conference :以某个国际会议为例,学习参加国际会议
Specialized English for Electrical Engineering
电气工程专业英语
1
Lecture 1 Introduction
引言
2
1.1 什么是专业英语
普通英语(Common English, Ordinary English)
科技英语(English for Science and Technology)
的流程。
5
Lecture 2
Features of Specialized English
专业英语的特点
6
2.1 Grammar Features 语法特点
客观性(Objective)、准确性(accuracy)和精练性(conciseness)。 (1) 广泛使用被动语态 (2) 广泛使用非谓语形式 (3) 省略句使用频繁 (4) It句型和祈使句使用频繁 (5) 复杂长句使用频繁 (6) 后置形容词短语作定语多
① 动名词
✓用动名词短语取代时间从句或简化时间陈述句
1)The signal should be filtered before it is amplified. The signal should be filtered before being amplified. 放大信号前,应先对其进行滤波
1
2
常用符号公式表达
2
3
Unit 1 The basis of electricity and its Applications Nhomakorabea4
电学及应用基础
3
5
Unit 2 Transmission and Distribution Systems
6
输电配电系统
4
7
Unit 3 High Voltage Engineering
电能是在发电站或发电厂产生的 4) The meters are calibrated and the scale is designed to read the
value of the desired unit.
这些仪表可以被校准并且设计了不同的量程 ,以便读出期望的数值。
5) Electrical energy can be stored in two metal plates separated by an insulation medium. Such a device is called a capacitor, and its ability to store electrical energy is termed capacitance. It is measured in ’Farads.
专业英语与科技英语既有区别又有联系。专业英语的学习需要有一个良好的 科技英语基础,同时也要注意其自身的词汇特点、语法特点、修辞特点和翻 译特点等等。
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1.2 学习专业英语的重要性
(1) 科研信息获取 专业英语阅读能力
当前大部分资料都可以通过互联网传播,而这些资料中90%以上都 是英语。 世界上科技情报资料的交流主要靠使用英语,对子电气工程、电子工 程和信息类等专业来说,绝大部分专业资料和信息都是以英语形式出 观。
2)Instrument transformers are installed on the high-voltage equipment. 互感器安装在高压设备上
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2.1 Grammar Features
3) Electric power is generated in power generating stations or plants.
2) An object becomes hot. It is placed in the sun. Once being placed in the sun, an object becomes hot. 物体放置在太阳下会变热。
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2.1 Grammar Features
3) We must do various experiments before a new electronic product is designed. Before designing a new electronic product we must do various experiments.
专业英语(English for Special Science and Technology)
隶属于科技英语 是科技英语的一部分,以表达科技概念、理论与事实为主要 目的。遵守科技英语的语法体系和翻译方法;特别注重客观事实和真理,表达准 确、精练和正式。
是结合各自专业的科技英语 有很强的专业性,涉及的面更加狭窄,与专业内 容配合更为密切。
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