首页 > 题库 > 考研考博 > 考博英语 > 河北工业大学 > 单选题

First, let’s consider what a nuclear reactor is: a (1), glowing red-hot coal. That’s a (2) way of describing it, anyway. Nuclear reactors, just like fossil fuel-burning power plants, make electricity by (3) water so it turns into steam and (4) a turbine, which powers a generator.
To use another (5), the nuclear fission which (6) this heat is a bit like the chaos you’d get if you toppled a giant pyramid of (7) tomatoes. First, one can would fall, and then it would bounce off several more cans, (8) those over, and then they’d all bounce downhill, creating an ever-expanding chain reaction. And each time a can hit another can, it would produce a spark of heat.
In Japan, this chain reaction stopped at the time of the earthquake, when the reactors shut down as a safety (9). But nuclear fission produces such (10) amounts of heat that it takes a long time for the reactor core to cool. Plus, the fissile (11) keeps giving off what’s called “decay heat” as it continues to (12) radiation. Right after shutdown, a nuclear reactor is still producing large amounts of heat, so you’ve got a pretty big job keeping the whole thing cool.
Normally that’s done by circulating water around the core. But in Japan, the earthquake knocked out all means of moving this (13). Once that happens, the water can turn to steam, laced with hydrogen and other explosive elements. This (14) pressure in the containment building. That’s what caused the building explosions we’ve seen so far.
Japanese nuclear officials are (15) pumping sea water into the reactor buildings to try and (16) things off. But the pressure from the steam and (17) heat makes that much more difficult to do than it sounds. It appears that nuclear fuel rods, which contain the fissile stuff, have been (18) to air for some unknown period of time in several of the reactors. At that point, without cooling water surrounding them, the rods (which are zirconium, in case you were wondering) start to blister and buckle.
As they (19), the rods release radioactive fuel byproducts that normally they’d be able to contain. The open spaces between them—through which water normally would be able to flow—get blocked up, making it even harder for them to (20) heat, they melt, Hence the term—“meltdown.”

问题1选项
A.small
B.easy
C.difficult
D.giant
问题2选项
A.simplistic
B.human
C.philosophical
D.religious
问题3选项
A.putting up
B.staying up
C.making up
D.heating up
问题4选项
A.breaks
B.takes
C.drives
D.deteriorates
问题5选项
A.mythology
B.methodology
C.analogy
D.sociology
问题6选项
A.creates
B.steals
C.recruits
D.rebuilds
问题7选项
A.broken
B.canned
C.prepared
D.used
问题8选项
A.taking
B.knowing
C.kicking
D.knocking
问题9选项
A.response
B.reduction
C.reincarnation
D.restate
问题10选项
A.trivial
B.enormous
C.ridiculous
D.enabling
问题11选项
A.mechanic
B.material
C.metaphysic
D.metonymy
问题12选项
A.swallow
B.absorb
C.emit
D.infuse
问题13选项
A.cure
B.coexistence
C.coolant
D.coauthor
问题14选项
A.enables
B.increases
C.intakes
D.installs
问题15选项
A.despondently
B.discouragingly
C.disparagingly
D.desperately
问题16选项
A.burn
B.cool
C.take
D.set
问题17选项
A.continuing
B.continued
C.being continuing
D.being continued
问题18选项
A.exposed
B.exponent
C.exodus
D.excluded
问题19选项
A.upgrade
B.decrease
C.deform
D.upload50.
问题20选项
A.produce
B.disclose
C.disown
D.dissipate
参考答案: 查看答案 查看解析 查看视频解析 下载APP畅快刷题

相关知识点试题

相关试卷