【判断题】
水下焊接与切割,它与在大气中焊接与切割相比危险性较小。
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当压力为147kPa表压而温度超过580℃时,乙炔就产生爆炸分解。
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以气体为置换介质时,其用量为被置换容积的3倍以上。
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除了性质较稳定的金、铂、钛、银、钼、钉、铭、锹、依以外,其他金属都能被硝酸溶解。
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熔化焊机中不与地相连接的电气回路,在试验时对个别元件,由于特性限制,允许从电路中拆除或短接。
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焊接时电弧的可见光亮度比肉眼正常承受的光度大1000倍。
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自动焊和手工焊主要用于大型机械设备制造,其设备多安装 在厂房里,作业场所比较固定。
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气瓶储存时,空瓶与实瓶两者应分开放置,并有明显标志。
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熔化焊设备各个焊机间及与墙面间至少应留出1m宽的通道。
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在实际生产中,大多用氩气作为切割气体。
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在国家标准GB18218—2009《重大危险源》中,给出了各种危险物质的名称、类别及其临界量。
【判断题】
气瓶投入使用后,不得对瓶体进行挖补,但可焊接修理。
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在使用含有氟化物的钎剂时,必须在有通风的条件下进行焊|接,或者使用个人防护装备。
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气瓶在使用过程中,发现有严重腐蚀、损伤或对其安全可靠性有怀疑时,应提前进行检验。
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珠光体的性能介于奥氏体和渗碳体之间,结构钢很多是珠光体。
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钎焊作业的安全生产意在防止发生人身伤亡和财产损失等生产事故。
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硅是一种非金属,但却具备金属的部分性质。
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等离子弧焊或等离子弧切割时,可以用冷却水也可以不用冷却水。
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灭火剂是能够有效地破坏燃烧条件,使燃烧终止的物质。
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带压不置换焊割,要严格控制含氧量,使可燃气体的浓度大大超过爆炸上限。
【判断题】
使用等压式焊炬焊炬施焊时,发生回火的可能性大。
【判断题】
等离子电弧对弧长不敏感,所以焊枪喷嘴至工件的距离不像氩弧焊时要求那么严格。
【判断题】
铁素体的强度和硬度低,但塑性和韧性好,所以含铁素体多的钢就表现出软而韧的特点。
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氧-乙炔焰的堆焊工艺与气焊工艺不用的是对火焰能率的选择。
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随着钢中含碳量的增加,钢中渗碳体的量将减小。
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安全生产管理的基本对象是企业的员工,不涉及机器设备。
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埋弧自动堆焊机有两台焊机,要同时使用才能进行焊接工作。
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钨极氩弧焊按操作方式分为手工焊、半自动焊和自动焊三类。
【判断题】
工厂中使用激光焊优点多,投资少,见效快。
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职业病检查时应有5位以上取得职业病诊断资格的执业医师集体诊断。
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铝及铝合金的焊接特点是表面容易氧化,生成致密的氧化膜,影响焊接,容易产生气孔,容易产生裂纹。
【判断题】
等离子弧切割电流的大小与割口宽度呈正比例关系。
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电弧焊面罩既可防弧光和灼伤,又可减轻烟尘和有害气体对人体损害。
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Tom is a book lover. ______ likes reading very much.
A. He B. She C. You D. It
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—May I listen to the music here, Mr. White?
—Sorry, you’d better it like that．
A. not to do B. not do to
C. dont do D. not do
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3.—Did you have a good time at Lauras birthday party?
— Yes, indeed. Its several years ________ I enjoyed myself so much.
A. when B. before C. since D. that
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About three kilometers away. You can take the No. 35 bus.
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A. anything B. something C. nothing D. everything
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A. father; Browns B. father's; Browns
C. father; the Browns D. father's; the Browns
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7. She ______ very hard since she came to our school.
A. studies B. has studied C. is studying D. studied
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8. — Who will send you to the new school, your mom or your dad?
— _______. Ill go there by myself.
A. Both B. Either C. Neither D. None
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9.—Well do what we can ____English well this term．
—It’s high time for you to work hard．
A. study B．to study C. be studied D. be studying
【单选题】
10. —I’m going to Flower Bookstore. Could you tell me ______?
— Sorry, I don’t know. I’m new here.
A. where it is B. where was it C. where is it D. where it was
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11. How do you like the dishes, Eric?
— Fantastic! Nothing tastes ________.
A. nice B. better C. terrible D. worse
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12. ______ Lin Feng has to work late, she always wears a smile on her face.
A. Because B. If C. Until D. Though
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13.You can save money _______ you buy cheaper things.
A. before B. unless C. if D. until
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14. We will have a _________ holiday after the exam．
A. two-month B. two month’s C. two month D. two-months
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15. —We will build an underground in Xuzhou before 2015．
— Wow, _______! Will it pass our place?
A. what an excited news B. how excited the news is
C. what exciting news D. how exciting
【单选题】
16. — Emily, here’s a dictionary．I hope it will help you in some way．
— Thank you．It’s ________ what I need．
A. almost B. still C. only D. just
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17. —Oh．I’m hungry．Mum, can I have the hamburger on the plate?
—No．It tastes ．
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18. —We can invite our teachers to the farewell party next Saturday.
—Yes, ______? I’ll call them at once.
A. what for B. what C. why not D. why
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19.You can ________ ask the old man to move away to any other place because he has lived ________ here for at least sixty years．
A. hardly; alone B. hard; alone
C. hardly; lonely D. hardly; lonely
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20.—I’m going back to see my grandparents this weekend．
—________．
A. It’s very nice of you B. You’d better hurry
C. Say goodbye to them D. Give my best wishes to them
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21.—Why not take ____ umbrella with the sign “Made in China”? It is useful.
—What _______ good advice it is!
A. an; a B. a; a C. an; \ D. \; a
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22. —Do you know the boy________ is sitting next to Peter?
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23. It was dark, ______ I couldnt see what was happening.
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24.—You can use MSN to talk with Vivien on the Internet.
—I know. But can you tell me ________?
A. what I can use it B. when I can use it
C. why can I use it D. how can I use it
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25. _______ are you going to the School Uniform Exhibition, Amy ?
To learn about different styles of school uniform.
A. What B. Where C. Which D. Why
【单选题】
( ) 26. Where does the writer of "The little Prince" come from?
A．England． B．France． C．America． D．China．
【单选题】
( ) 27. What does the prince do after the fox tells him a secret?
A．He cares more about a flower and a sheep．
B．He meets many more strange adults on other planets．
C．He realizes his love for the rose and he goes back to his planet．
D．He discovers interesting things such as a snake, other roses and a fox
【单选题】
( ) 28. What does "The little Prince" mainly talk about? It' s about _________．
A．the adult world B．the planet B -612
C．a rose and a fox D．the adventure of a young prince
【单选题】
( ) 29. What is the writer's main purpose（目的）in writing this passage？
A．To tell the readers his life story．
B．To tell people what kind of person his father was．
C．To tell the readers what present he got from his father．
D． To let people know how poor he was．
【单选题】
( ) 30. Why did the father not ask his son not to do this and do that？
A．Because he felt quite confident of his son．
B．Because he was born from a poor family．
C．Because he was a man of few words．
D．Because he didn't want to be much too strict with his son．
【单选题】
( ) 31. What would someone learn from this passage？
A．How to live by oneself． B．How to stand on one's own feet．
C．What a good father should do． D．What the self-important is like．
【单选题】
( ) 32. What may be the proper Chinese for the underlined part in the passage？
A．闲暇时光 B．学费 C．精神空虚 D．经济不足
【单选题】
( ) 33. Why did Natalie Smith pay for the six cars behind her?
A. She had seven tickets.
B. She hoped to please others.
C. She knew the car drivers well.
D. She wanted to show kindness.
【单选题】
( ) 34. Judy Foreman copied down the phrase because she ___ .
A. thought it was beautifully written
B. wanted to know what it really meant
C. decided to write it on a warehouse wall
D. wanted her husband to put it up in the classroom
【单选题】
( ) 35. Who came up with the phrase according to the passage?
A. Judy Foreman. B. Natalie Smith. C. Anne Herbert D. Alice Johnson.
【单选题】
( ) 36. What can we infer from the last paragraph?
A. People should practice random kindness to those in need.
B. People who receive kindness are likely to offer it to others.
C. People should practice random kindness to strangers they meet.
D. People who receive kindness are likely to pay it back to the giver.
【单选题】
( ) 37.The greatest river for navigation is ___________.
A. the Nile B. the Amazon C. the Mekong D. the Mississippi
【单选题】
( ) 38. From a dam, people can use the water for ___________.
A. keeping the rivers clean B. only making electricity
C. irrigation and making electricity D. washing clothes
【单选题】
( ) 39. The water in the river is polluted because of _____________.
A. people's drinking water too much B. people's swimming in the river too much
C. chemicals and other materials D. people's building a dam across a river
【单选题】
( ) 40. The best title of the passage is ___________.
A. Rivers in Cities B. The importance of Rivers
C. Transportation D. Natural Resources
