(二) 阅读下面短文,回答下 * * 道题。 尘埃无处不有,虽然它们的个体很小,但汇聚起

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问题:

(二) 阅读下面短文,回答下 * * 道题。
尘埃无处不有,虽然它们的个体很小,但汇聚起来威力却不小。据记载,北美大陆在20世纪30年代发生的一次尘暴中,狂风将美国平原的泥土大量向东吹去,有难以估计的牲畜被尘埃窒息而死。尽管如此,尘埃的积极作用却是不可低估的。悬浮在大气中的尘埃粒子,能够将太阳光中的较短光柱拦截,使其进行有规则的发散,这样,才会使天空呈现蔚蓝,在太阳升起和降落时,由于阳光穿过较低层的空间,空气中的尘埃密度大,并伴有水汽,可以吸收和反射阳光中的黄色和红色部分,因此,这时看到的太阳呈现橙色、红色和黄色。气象学家指出,在降雨时,每一个雨滴都必须有一颗尘埃参与,以它作为核心,水汽在其周围凝结,形成云、雾,再由云层形成雨点。若是纯净的空气中没有尘埃的存在,水分子无所依附,就不能形成雨滴降落。此外阳光在射向地球的时候,因受到尘埃的吸收和反射,能使地球上的生物得到适量的光照,以满足生长发育所需要。
现代科学发现,有的尘埃在一定的条件下会发生爆炸,这种现象被称作“尘炸”。据解析,能够产生尘炸的物质有粮食粉尘、砂糖、奶粉、咖啡、金属粉末以及其他非金属粉末等。物质发生爆炸,是一种剧烈的化学反应。而化学反应的速度与反应物质的颗粒大小有关。物质分散得越细,颗粒越小,它的表面积就越大。与具有固定面积的物质相比,接触空气吸附氧分子多,氧化和放热的过程都很快,反应性能就更活泼。当其中的某一质点被火点燃,就会发生连锁反应,产生爆炸。此外,易爆尘埃的颗粒越细,浓度越大,它所产生的爆炸力就会越强。当粉尘含量低于大气含氧量一半时,就不会引起爆炸,物质形成“尘炸”,还和诱因、速度等因素有关。产生“尘炸”的诱因很多,其中最主要的是摩擦冲击以及电器设备或静电产生的火花。
随着现代城市的迅速发展,人们发现尘埃已经成为一种危及环境和人类健康的污染物。流行病学家对尘埃进入人体后的机理进行研究后指出,人们在呼吸时,每次大约要吸入50万个浮游微粒;这些微粒进入人的身体后,可以一直进入肺部深处,并作为经常性刺激物留在那里,它会导致发生炎症,产生黏液,使人呼吸困难,甚至导致死亡的发生。除此之外,浮游微粒还可以向肺部传送化学污染物,而且在传送过程中,可以加速一种叫做游离基的有害物质的产生,从而进一步加剧有害物质对人体的危害程度。进入人体内的浮游微粒尘埃,主要来源于工业废弃物、汽车尾气及建筑、装饰材料中的化学成分。资料表明,在我们生活环境内排放的浮游微粒70%来自人为因素。另据调查,哮喘病、肺炎、心脏病等疾病的发病率,都与浮游微粒的增减有关。
(节选自《百科知识》2002年7月份)

根据原文所提供的信息,以下推断不正确的一项是( )。

A.加强机器的维护保养,不过度使用机器,防止摩擦起火是防止“尘炸”的一种有效方法

B.只要粉尘含量超出大气含氧量一半时,就会发生爆炸,所以,我们要随时测量粉尘含量是否超出大气含氧量的一半

C.在容易产生“尘炸”的厂房车间内,配备足够的通风设施,可以降低尘埃的浓度,从而防止“尘炸”的发生

D.如果我们通过治理,能够有效地减少空气中浮游微尘的数量,就能大大地降低哮喘病、肺炎、心脏病等疾病的发病率

考点:在职联考GCT(语文)工程硕士(GCT)语文
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  “这是植物生物工程技术结出的第一批硕果。这门新学科可能会给农业带来革命性的变化。”理解课文《绿色基因的革命》含义,结合加粗的词,解释这句话的含意。

答:_____________________________________。

题型:单项选择题

Agatha Christie went out at night.She never forgot the night when she met a robber many years ago.

That evening, she was invited to a birthday party which lasted until 2 o’clock in the morning.Agatha walked in the quiet street alone. Suddenly from the shadow of a dark building a tall man with a sharp knife in his right hand ran out at her. “Good morning, lady,” the man said in a low voice, “I don't think you wish to die here!”

“What do you want?” Agatha asked.

“Your earrings(耳环). Take them off!”

Agatha suddenly had a bright idea. She tried to cover her necklace with the collar (衣领 ) of her overcoat while she used the other hand to take off both of her earrings and then she quickly threw them on the ground.

“Take them and let me go,” she said. The robber saw that the girl didn’t care for the earrings at all, only trying to protect the necklace. He thought the necklace would cost more, so he said, “Give me your necklace.”

“Oh, sir. It’s not worth much. Please let me keep it.”

“Stopping rubbish(废话). Quick!”

With shaky hands, Agatha took off her necklace. As soon as the robber disappeared, she picked up her earrings and ran as fast as she could to one of her friends.

The earrings cost 480 pounds and the necklace the robber had taken away cost only six pounds.

小题1:Agatha never forgot the night, for she _______.

A.was robbed of her earrings

B.had a good time at the birthday party

C.was robbed of her necklace

D.was robbed, but she fooled the robber小题2:The birthday party ___________.

A.was over at 2

B.didn’t end after 2

C.ended before 2

D.didn’t end at 2小题3:Which of the following is not true? ______.

A.Agatha pretended not to care for her earrings

B.Agatha pretended to care for her necklace

C.Agatha really cared for her earrings

D.Agatha didn’t care for her earrings at all because they were not too expensive小题4:After reading the story,you may know that Agatha was a _____ girl.

A.brave and famous

B.clever and brave

C.foolish

D.beautiful

题型:单项选择题

与固有免疫相比,适应性免疫应答的特点有()

A.非特异性

B.特异性

C.记忆性

D.耐受性

E.多样性

题型:单项选择题

在一项社会调查中,调查员向被调查者询问“你经常大量吸烟喝酒吗”属于

A.诱导型问题
B.开放式问题
C.复合型问题
D.封闭式问题
E.敏感型问题

题型:单项选择题

计算分子生物学

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