答案与题解：

1.  c   短文第一段的第二、第三句提供了答案。

2.  a   文章第二段的第二句说，科学家正在研制一艘可将研究人员带到6,500米深处的潜水装置，而它将替代 alvin，因为 alvin 只能潜到4,500米深处。a 不是事实，所以是正确选择。

3.  c   本文讨论探索海底世界的潜水装置，所以“充满神秘色彩的世界”指的就是海洋。

4.  d   第四段的头三个句子告诉我们，hov 和 alvin 在体积上和容量上相似。所以 d 是正确选择。

5.  d   第四段最后两句告诉我们，alvin 只有三个窗户，而 hov 有五个。最后一段告诉我们，两艘潜水装置的上下活动速度和行进速度有所差别。所以 d 是正确选择。

9. plant gas (c级)

（替换2007年用书理工类阅读理解第二十一篇：the gene industry）

scientists have been studying natural sources of methane for decades but hadn’t regarded plants as a producer, notes frank keppler, a geochemist at the max planck institute for nuclear physics in heldelberg, germany¹. now keppler and his colleagues find that plants, from grasses to trees, may also be sources of the greenhouse gas. this is really surprising, because most scientists assumed that methane production requires an oxygen-free environment.

previously, researchers had thought that it was impossible for plants to make significant amounts of the gas. they had assumed that microbes² need to be in environments without oxygen to produce methane. methane is a greenhouse gas, like carbon dioxide. gases such as methane and carbon dioxide trap heat in earth’s atmosphere and contribute to global warming.

in its experiments, keppler’s team used sealed chambers that contained the same concentration of oxygen that earth’s atmosphere has. they measured the amounts of methane that were released by both living plants and dried plant material, such as fallen leaves.

with the dried plants, the researchers took measurement at temperatures ranging from 30 degrees celsius to 70 degrees c. at 30 degrees c, they found, a gram of dried plant material released up to 3 nanograms of methane per hour. (one nanogram is a billionth of a gram.) with every 10-degree rise in temperature, the amount of methane released each hour roughly doubled.

living plants growing at their normal temperatures released as much as 370 nanograms of methane per gram of plant tissue per hour. methane emissions tripled when living and dead plant was exposed to SUNlight.

because there was plenty of oxygen available, it’s unlikely that the types of bacteria that normally make methane were involved. experiments on plants that were grown in water rather than soil also resulted in methane emissions. that’s another strong sign that the gas came from the plants and not soil microbes.

the new finding is an “interesting observation,” says jennifer y. king, a biogeochemist at the university of minnesota in st. paul³. because some types of soil microbes consume methane, they may prevent plant-produced methane from reaching the atmosphere. field tests will be needed to assess the plant’s influence, she notes. (367 words)

词汇：

　　methane n. 甲烷，沼气

　　emission n. 散发，发射

　　geochemist n. 地球化学家

　　triple v. 增加三倍；adj. 三倍的

　　celsius n & adj. 摄氏（的）

　　bacteria n. （bacterium的复数）细菌

　　microbe n. 微生物

　　nanogram n. 微克

　　biogeochemist n.生物地球化学家

　　chamber n. 室，房间；腔

注释：

1.  the max planck institute for nuclear physics in heldelberg, germany：马克思·普朗克核物理研究所，位于德国海德堡。海德堡系德国西南部城市，在巴登－符腾堡州的内卡河畔。海德堡大学是德国历史最悠久的大学。

2.  microbe：细菌，意义同 bacterium（bacteria的单数形式），但 microbe 不用作专门术语。

3.  st. paul：圣保罗，美国明尼苏达州首府。

练习：

1.       what was scientists’ understanding of methane?

a) it was produced from plants.

b) it was not a greenhouse gas.

c) it was produced in oxygen-free environments.

d) it traps more heat than any other greenhouse gas.

2.       to test whether plants are a source of methane, the scientists created

a) a oxygen-free environment.

b) an environment with the same concentration of oxygen as the earth has.

c) a carbon dioxide-free environment.

d) an environment filled with the greenhouse gas

3         which statement is true of the methane emissions of plants in the experiment?

a) the lower the temperature, the higher the amount of methane emissions.

b) living plants release less methane than dried plants at the same temperature. tsI'bK~s\c=?O78Tg[本文 来源 于我 的学习 网外语园地职称英语 hTTp://wWW.gZU521.cOM )tsI'bK~s\c=?O78Tg

c) when exposed to sunlight, plants stop releasing methane.

d) the higher the temperature, the greater the amount of methane emissions.

4.  what of the following about methane is not mentioned in the passage ?

a) plants growing in soil release methane.

b) plants growing in water release methane.

c) soil microbes consume methane.

d) microbes in plants produce methane.

5.  what is the beneficial point of some microbes consuming plant-produced methane?

a) methane becomes less poisonous.

b) methane is turned into a fertilizer.

c) less methane reaches the atmosphere.

d) air becomes cleaner..

答案与题解：

1.  c   短文的第一和第二段都讲到，科学家过去曾经认为，沼气必须在无氧的环境中才能产生。注意，作者用的是过去式：most scientists assumed that …， they had assumed that…。

2.  b   第三段第一句说，科学家使用密封的房间来做实验，房间里氧气的浓度与地球大气中的氧气浓度相仿。所以 b 句符合原文的意思，其它三个选择则不符合原文内容。

3.  d   根据第四和第五段的内容，只有 d 是正确的说法。温度越高沼气的释放量越高，有生命的植物释放的沼气远大于干植物的释放量，在阳光下，它们的沼气释放量是正常情况的三倍。

4.  d    最后两段告诉我们，无论在土壤中还是在水中生长的植物都能释放沼气，土壤中的微生物消耗沼气，使沼气不至于进入空气。所以a、b、c 的内容均符合短文最后两段中作者的意思。d 的内容短文中没有提到。

5.  c   最后一段的第二句可以找到本题的答案。

10. smart window (b级)

（替换2007年用书理工类阅读理解第三十三篇：star quality）

windows not only let light in to cut down an electricity use for lighting, but the light coming through the window also provides heat. however, windows are not something people typically associate with being a cutting edge¹ technology. researchers are now working on new technologies that enable a window to quickly change from clear to dark and anywhere in between with a flip of a switch².

“it took us a long time to figure out what a window really is,” says claes granqvist. he’s a professor of solid-state physics at uppsala university in sweden³. “it’s contact with the outside world. you have to have visual contact with the surrounding world to feel well.” so, windows and natural light are important for improving the way people feel when they’re stuck indoors.

yet, windows are the weak link in a building when it comes to energy and temperature control. in the winter, cold air leaks in. when it’s hot and sunny, sunlight streams in. all of this sunlight carries lots of heat and energy. and all of this extra heat forces people to turn on their air conditioners. producing blasts of cold air, which can feel so refreshing, actually suck up enormous amounts of electricity in buildings around the world.

windows have been a major focus of energy research for a long time. over the years, scientists have come up with a variety of strategies for coating, glazing, and layering windows to make them more energy efficient. smart windows go a step further. they use chromogenic technologies which involve changes of color.

electrochromic windows use electricity to change color. for example, a sheet of glass coated with thin layers of chemical compound such as tungsten oxide works a bit like a battery. tungsten oxide is clear when an electric charge is applied and dark when the charge is removed, that is, when the amount of voltage is decreased, the window darkens until it’s completely dark after all electricity is taken away. so applying a voltage determines whether the window looks clear or dark.

one important feature that makes a smart window so smart is that it has a sort of “memory.” all it takes is a small jolt of voltage to turn the window from one state to the other. then, it stays that way. transitions take anywhere from 10 seconds to a few minutes, depending on the size of the window. the development of smart windows could mean that massive air conditioning systems may no longer need. “in the future,” granqvist says, “our buildings may look different.

词汇：

　　flip n. & v. 用手指轻弹，轻击

　　tungsten oxide 氧化钨

　　air conditioner 空调（器）

　　jolt n. & v. 震摇，颠簸，晃动

　　refreshing adj. 使人清爽的

　　electrochromic adj. 电致变色的

　　glaze v. 装玻璃，用玻璃覆盖

　　voltage n. 电压

　　chromogenic adj. 发色的

　　air conditioning 空调，空调系统

注释：

1.  cutting edge：本意为：(刀片的)刃口, 刀刃；比喻意为：最先进的，科技含量最高的。
2.  anywhere in between with a flip of a switch：就在开或关的一霎那。

3.  uppsala university in sweden：瑞典的乌普萨拉大学。乌普萨拉是瑞典东部一座城市，位于斯德哥尔摩的西北方向。