Part I Listening and Speaking Activities Introduction of functions Listen and speak Try to speak more Make your own dialogue What are they for? If you want to learn more

3.1 核外电子的运动状态 一、 玻尔的原子结构理论 二、 电子的玻粒二象性 三、 玻函数与原子轨道 四、 概率密度和电子云图形 五、 四个量子数 3.2 核外电子的排布和元素周期律 一、多电子原子的能级 二、核外电子的排布的原则 三、原子的电子层结构和元素周期系 3.3 元素性质的周期性 一、有效核电荷(Z*) 二、原子半径(r) 三、电离能(I) 四、电子亲和能(Y) 五、电负性(x) 六、元素的金属性和非金属性 七、元素的氧化值

1.檐沟外排水(水落管外排水)(小型屋面) 雨水→屋面→檐沟→水落管一散水坡→地面檐沟→铅皮、预制砼 水落管→白铁皮、铸铁管。d=75~100mm,间距8~16m 2天沟外排水:利用屋面构造上所形成的天沟本身容量和坡度排泄雨水(大型屋面) 雨水→屋面一天沟→立管一地面或管道 天沟长度:40~50m,i=0.003

本节先介绍极限存在准则利用它们来导出两个重 要极限. 一、极限存在准则 准则I(夹逼定理)若Vx∈U(x,)(或|x>M), 均有g(x)≤f(x)≤h(x)且limg(x)=limh(x)=A, 则有limf(x)=A

Part I Listening Comprehension (20 minutes) Directions: In this section, you will hear ten short conversations. At the end of each conversation, a question will be asked about what was said. Both the conversation and the question will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A),),) and D),and decide which is the best answer. Then mark the corresponding letter on the Answer Sheet with a single line through the center

Part I Listening Comprehension (20 minutes) Directions: In this section, you will hear ten short conversations. At the end of each conversation, a question will be asked about what was said. both the conversation and the question will be spoken only once. After each question there will be a pause During the pause, you must read the four choices marked A), B), C)and D), and decide which is the best answer

Part I Listening Comprehension (20 minutes) Directions: In this section, you will hear ten short conversations at the end of each conversation, a question will be asked about what was said. both the conversation

Part I Listening Comprehension (20 minutes) Directions: In this section, you will hear ten short conversations At the end of each conversation, a question will be asked about what was said. both the conversation and the question will be spoken only once. After each question there will be a pause During the pause, you must read the four choices marked A), B), C)and D),and

试题一及答案 Part I Listening Comprehension (20 minutes) Section A Directions: In this section, you will hear 10 short conversations. At the end of each conversation, question will be asked about what was said. Both the conversation and the question

本章主要介绍可编程控制器基础知识。要 求了解可编程控制器的硬件结构、软件系 统和用户程序的特点;熟悉可编程控制器 的性能指标、扫描周期、I/0响应时间;掌 握可编程控制器的扫描工作方式的基本原 理