立井井筒设计的主要内容有哪些?

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问题:

立井井筒设计的主要内容有哪些?

考点:井巷工程井巷工程题库
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阅读下面短文,回答下列问题。
要说清楚纳米科技的真正涵义不是一件易事。“纳米”只是一个长度单位,大约是10个氢原子排列起来的长度。纳米科技被广泛地定义为纳米尺度空间(如从一纳米至几百纳米)的科学技术。当科学家和工程技术人员力图在用纳米尺度来理解和控制物质的时候,就会发现许多新的现象,发明许多新的技术。用纳米颗粒粉体制成的纳米材料或具有纳米尺度晶粒的材料会显示出比一般材料更优异的性能。光刻技术的不断进步,已经使芯片的制造技术正在接近或达到100纳米,使计算机的速度越来越快,而体积越来越小。这些科技进步对工业技术发展和社会进步都具有重要意义。然而,这并不是科学家们正在探索研究的纳米科技的核心和本质,这一切不过都是传统显微加工技术的扩展和延伸而已。它们都是通过采用类似于车床、铣床、钻床等加工设备,通过“切削”材料加工成所需的产品。这种技术统称为“由上到下”或“由大到小”的加工技术。纳米科技的核心和本质在于人们创造物质的生产方式将完全不同于自石器时代以来人类用工具创造物质世界的方式,而绝不仅仅是一个长度单位所能涵盖的。纳米科技绝不意味着制造纳米尺度的产品,纳米产品可以小到分子尺度,大到汽车、飞机,只是制造的方式完全不同罢了。
要理解纳米技术的真正涵义还须从纳米技术思想的起源开始。纳米技术的灵感来自于已故美国物理学家查理·范曼的演讲,他在1959年向加州理工学院的同事们提出了一个新的想法。从石器时代开始,人类从磨尖箭头到光刻芯片的所有技术,都与一次性地削去或者融合数以亿计的原子以便把物质做成有用的形态有关。范曼质问道,为什么我们不可以从另外一个角度出发,从单个的分子甚至原子开始进行组装,以达到我们的要求呢实际上这一灵感来自于大自然从单个分子,甚至单个原子创造物质的启示。如果把人体分解成组成它的基本单元,我们获得的将是一小桶的氧、氢和氮,一小堆碳、钙和盐,微量的硫、磷、铁和镁,以及微不足道的20种或更多的其他化学元素。它们的总价值可以说是微不足道的。然而,大自然就是采用它们自己的、科学家们称之为纳米工程的方法,把这些廉价的、丰富的、无生命的单元转成具有自生成、自维持、自修复、自意识能力的生灵,可以行走、扭动、游泳,具有嗅觉和视觉,甚至可以思想和做梦,其价值无与伦比。因此,纳米技术就是向大自然学习,力图在纳米尺度精确操纵原子或分子来制造产品的技术,统称为“由底向上”或“由小到大”的加工技术。
科学家们已经或正在意识到纳米科技将给人类带来的社会变革。由于可能通过精确地控制原子或分子制造新产品,生产过程将变得非常清洁,将不产生副产品和废物。纳米技术将采用资源丰富的元素来制造完美的金刚石材料,不仅强度会比钢高几十倍,而且重量仅是钢的几十分之一。利用纳米技术,人类有可能在原子和分子尺度诊断和治愈疾病,甚至修补细胞。纳米技术将可以制造分子开关和导线,从而将导致一场计算机制造技术的革命。
(节选自张永刚《纳米科技的迷雾》)

下列说法不属于“由小到大”的加工技术的一项是______。

A.与大自然从单个分子甚至原子创造物质的方式一样

B.从单个分子或原子开始进行重组、装配来生产产品

C.与凭借类似于车床、钻床等加工设备“切削”材料加工产品的方式完全不一样

D.在纳米尺度,一次性地削去或者融合数以亿计的原子,以制造新的物质产品

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Happiness is for everyone. You don’t need to care about those people who have beautiful houses with large gardens and swimming pools or those who have nice cars and a lot of money and so on. Why? Because those who have big houses may often feel lonely and those who have cars may want to walk on the country roads at their free time.

In fact, happiness is always around you if you put your heart into it. When you are in trouble at school, your friends will help you; when you study hard at your lessons, your parents are always taking good care of your life and your health; when you get success, your friends will say congratulations to you; when you do something wrong, people around you will help you to correct it. And when you do something good to others, you will feel happy, too. All these are your happiness. If you notice a bit of them, you can see that happiness is always around you.

Happiness is not the same as money. It is a feeling of your heart. When you are poor, you can also say you are very happy, because you have something else that can’t be bought with money. When you meet with difficulties, you can say loudly you are very happy, because you have more chances to challenge(向…挑战)yourself. So you can not always say you are poor and you have bad luck. As the saying goes, life is like a revolving(旋转)door. When it closes, it also opens. If you take every chance you get, you can be a happy and lucky person.

小题1:Those who have big houses may often feel         .

A.happy

B.lonely

C.free

D.excited小题2:When you fall down in a PE class, both your teacher and your classmates will     .

A.laugh at you

B.play jokes on you

C.quarrel with you

D.help you up小题3:What will your friends say to you when you make great progress?

A.Oh, so do I

B.Congratulations

C.Good luck

D.It’s just so-so小题4: Which idea is NOT right according to the passage?

A.People who have cars would never like to walk in the open air

B.You can get help from others when you make mistakes

C.You can still be a happy person even if you have little money

D.Happiness is always around you though difficulties come towards you小题5: Which of the following is this passage about?

A.Bad luck

B.Good luck

C.Happiness

D.Life

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流行病学研究方法主要分为______,______和理论研究三大类。

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患者,女,45岁。体重50kg,急性肾衰竭多尿期,厌食,恶心,呕吐,脉压变小,血压下降,测血钠125mmol/L,按血钠浓度计算出的补钠量约为( )

A.5g
B.10g
C.15g
D.20g
E.25g

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