Uint I. Basic listening practice 1. Script W: Have you chosen your elective for next semester yet? Are you taking Frenc riting again? M: Yes I am, but it's compulsory for us next semester. So i think I'm gong to do marketing as an elective instead

Uints I. Basic listening practice 1. Script W: Why do some people stay in one job for life while others switch jobs from time to M: Some people want a fixed routine so that they dont have to adapt tot new circumstances over and over again, while others think variety is the spice of life Q: According to the dialog, why do some people stick to one job for life?

Uints I. Basic listening practice 1. Script W: I bought a camera from your store. Here's my receipt. I know it's just warranty period, but the camera hasn't worked properly for some time, and now it's not focusing at all. M: We're sorry you've has problem with one of our cameras. I t seems that the camera has suffered some damage, but you've been a regular customer, and wed

Ⅱ. Listening skills Listening for People' s Food Preferences 1. M: Jenny, the main courses here are steak, chicken or fish. Each comes with rice. So, what looks good to you? W: Gee, I had chicken last night, and I often eat fish for dinner. Maybe I'll have steak

Uinta I. Basic listening practice 1. Script M: Do you see yourself as a leader or more of a team player? W: Well, it depends on the circumstances. I usually enjoy working as part of a team and helping everyone work together. But if the leadership is weak, I'm not afraid to take over in order to achieve the goal at hand Q: What does the woman want to be?

Uinta I. Basic listening practice 1. Script M: Did you pick up the paper for me today? i really want to check the job vacancies W: I know, it's over there. There's not much happen though. I had a look already Maybe you should look on the Net instead

Ⅱ. Listening skills Listening for Telephone numbers 1. W: I' m wondering if the weather will be good for us to go cycling on Saturday M: Let's call the weather office. I know the phone number. It's 661-3047. If the weather is going to be bad, we'll have to wait for another week Q: What's the phone number for the weather office?

Uint IL. Basic Listening Practice 1. Script W: Did you see the paper today? There was an earthquake in brazil M: Yes, but it only measured 3. 5 on the Richter scale. I dont think there were any casualties

第二十章过渡金属(〡) 20—1概述 一、什么是过渡金属:不同书本有不同的分法具有部分充填d或f亚层电子的元素: 列元素 据此人们常将Cu族也纳入过渡金属元素,因为:也有书上把Zn族也归入,因此,过渡元素性质非常丰富,有最高熔点的W,最大硬度的Cr,也 有常温液态的Hg,还要延展性最好的Au,导电性最好的Ag等

1911年荷兰物理学家昂内斯(H. Onnes)在研究水银在低温下的电阻时,发现当温 度降低至4.2K以下后,水银的电阻突然消失呈现零电阻状态。昂内斯便把这种低温下 物质具有零电阻的性能称为超导电性。1933年迈斯纳(W. Meissner和奥克森菲尔德(r Ochsenfeld)发现,不仅是外加磁场不能进入超导体的内部,而且原来处在外磁场中的正 常态样品,当温度下降使它变成超导体时也会把原来在体内的磁场完全排出去到1986 年,人们已发现了常压下有28种元素、近5000种合金和化合物具有超导电性