右图是电子感应加速器的示意图，上、下为电磁铁的两个磁极，磁极之间有一个环形真空室

发布时间：2017-06-23 20:10 │ 来源：www.tikuol.com

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右图是电子感应加速器的示意图，上、下为电磁铁的两个磁极，磁极之间有一个环形真空室，电子在真室室中做圆周运动。上图为侧视图，下图为真空室的俯视图。电子从电子枪右端逸出（不计初速度）后，在真空室中沿虚线被加速，然后击中电子枪左端的靶，下列说法正确的是

A．俯视看，通过电磁铁导线的电流方向为顺时针方向

B．俯视看，通过电磁铁导线的电流方向为逆时针方向

C．通过电磁铁导线的电流应逐渐减小

D．通过电磁铁导线的电流应逐渐增大

考点：电磁感应现象的综合应用

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眶蜂窝织炎的发病，说法正确的是( )

A．最常见的致病菌为金黄色葡萄球菌和绿脓杆菌

B．成人较儿童更易发生

C．大多由全身感染性病变血源性转移而来

D．多伴有穿通性眼外伤

E．由于眶内、面部、鼻窦静脉均无瓣膜，血管相互沟通，因此邻近组织的感染易通过静脉扩散至眶内

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以下各线大致与秦岭--淮河一线一致的有（　　）

①湿润区与半湿润区的分界线 ②亚热带与暖温带的分界线 ③1000毫米年等降水量线

④一月份0℃等温线 ⑤暖温带与中温带的分界线 ⑥半湿润区与半干旱区的分界线．

A．①②⑤

B．②④⑥

C．①②④

D．②⑤⑥

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阅读理解。

Su Hua is studying at Cambridge, UK. She has bought a bicycle and is worried about security (安全).
Her friend, Kate, found this article and sent it to her.

Introduction
A lot of crime is against bicycles. About 150,000 bicycles are stolen every year
and most are never found. You can prevent this happening by following a few
careful steps.
Basic Security
Do not leave your bicycle in out-of-the-way places. Always lock your bicycle when you leave. Secure it to lampposts or trees. Take off smaller parts and
take them with you, for example lights and saddles (车座).
Locks
Get a good lock. There are many different types in the shops. Buy one that
has been tested against attack. Ask for a recommendation from a bike shop.
Marking
Security marking your bike can act a deterrent to a thief. It can also help the
police find your bicycle. It should be clearly written and include your postcode and your house or flat number. This will provide a simple way to identify your bicycle.
Registration
There are a number of companies who will security mark your bicycle for you. They will then put your registration number and personal details on their
computer database. Then if your bicycle is found it will be easy to contact you.
Finally
Keep a record of the bicycle yourself: its make, model and registration number. You can even take a photograph of it. This will prove the bicycle belongs to
you.

1. Which part of the text gives you information on how to lock up your bicycle when you leave it?

A. Locks.
B. Marking.
C. Registration.
D. Basic Security.

2. The underlined phrase "act as a deterrent to a thief" means _____.

A. help you recognize your bike
B. help the police find your bicycle
C. stop someone stealing your bicycle
D. stop you worrying about your bike

3. The article advises you to keep a record of your bicycle ______.

A. in the bike shop and your computer
B. in the police station and a security company
C. in a security company and your university
D. by yourself and in a security company

4. The main purpose of this article is _____.

A. to tell you what to do if your bicycle is stolen
B. to suggest ways of keeping your bicycle safe
C. to give you advice on where to buy a good lock
D. to say why you shouldn't keep your bicycle in a quiet place

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学校在国家出现之后产生，首先是适应统治阶级（）的需要。

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* * 为什么要强调学习科学发展观和学习法律知识？

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