What will power your house in the future?Nuclear,wind,or solar power?According to scientists at the Massachusetts Institute of Technology(MIT)in the US,it might be leaves—but artificial(人造的)ones.
Natural leaves are able to change sunlight and water into energy. It is known as photosynthesis(光合作用).Now researchers have found a way to imitate this seemingly simple process.
The artificial leaf developed by Daniel Nocera and his colleagues at MIT can be seen as a special silicon chip with catalysts(催化剂).Similar to natural leaves,it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell,which uses those two materials to produce electricity,located either on top of a house or beside the house.
Though the leaf is only about the shape of a poker card,scientists claimed that it is promising to be an inexpensive source of electricity in developing countries.“ One can imagine villages in India and Africa not long from now purchasing an affordable basic power system based on this technology,”said Nocera at a conference of the American Chemical Society.
The artificial leaf is not a new idea. The first artificial leaf was invented in 1997 but was too expensive and unstable for practical use. The new leaf,by contrast,is made of cheap materials,easy to use and highly stable.In laboratory studies,Nocera showed that an artificial leaf prototype(原型)could operate continuously for at least 45 hours without a drop in activity.
The wonderful improvements come from Nocera's recent discovery of several powerful,new and inexpensive catalysts. These catalysts make the energy transformation inside the leaf more efficient with water and sunlight. Right now,the new leaf is about 10 times more efficient at carrying out photosynthesis than a natural one. Besides,the device can run in whatever water is available;that is,it doesn't need pure water. This is important for some countries that don't have access to pure water.
With the goal to “make each home its own power station” and “give energy to the poor”,scientists believe that the new technology could be widely used in developing countries,especially in India and rural China.
33.Which of the following orders correctly shows how the artificial leaf is used to produce electricity?
a.artificial leaves split water into hydrogen and oxygen
b.the hydrogen and oxygen gases are stored in a fuel cell
c.the artificial leaves are put in water
d.the fuel cell uses hydrogen and oxygen to produce electricity
A.c,b,a,d B.c,a,b,d
C.b,c,a,d D.c,a,d,b
34.The purpose of the scientists at MIT in developing the new artificial leaf is to________.
A.build up more power stations in the world
B.provide cheaper energy for developing countries
C.offer people in developing countries access to pure water
D.gain a deeper understanding of the photosynthesis process
35.The main idea of this passage is ________.
A.an introduction to the history of artificial leaves
B.an invention copying photosynthesis
C.giving energy to the poor
D.a mixture of water power and solar energy
BBB
新闻报道类阅读的概念:
阅读理解的选材明显地呈现出关注实际生活的趋势,这种趋势与当前基础教育改革的目标是一致的,而中学生学习语言的根本目标与基础教育学会求知,学会做事,学会合作,学会做人的目标是一致的,真实新颖的选材对基础英语教学课程改革具有重要的反作用。
新闻报道类阅读理解技巧点拨:
新闻报道类类文章有一共同特点,即都是由标题(Headline)、导语(Lead)、主体(Mainbody)、背景(Background)和结尾(End)五部分构成。标题是新闻报道中心思想高度而又精辟的概括;导语位于新闻报道的首段,高度概括新闻事实;主体则对导语概括的新闻事实进行详细叙述;新闻背景是指新闻事实之外,对新闻事实或新闻事实的某个部分进行解释或补充的材料;结尾往往是新闻事件的结果或动态展望,也是中心思想的概括并常常与新闻导语相呼应。
新闻报道中的导语非常重要,它位于文章的第一段,通过它点出新闻的主题,五个W和一个H(When,Where,Who,What,Why和How)通常是构成一则完整消息不可缺少的要素。文章往往呈现出“倒金字塔”的特征,因此读懂首句或首段至关重要。
另外,从句的使用也是此类文章的一大语言特色,因为从句信息量大,适合新闻报道的要求。此外,大量的副词和插入语的使用也是此类文章的特点。为使文章更客观、更具信服力,常用The study said…, Scientists believe that…Experts said…, It's reported that…, According to the survey…等语言。同事在阅读过程中,我们要对材料所提供信息如when, where, who, how, why等进行提问,将信息迅速提炼出来。
新闻报道类阅读应试策略:
【命题趋势】
阅读理解的选材明显地呈现出关注实际生活的趋势,这种趋势与当前基础教育改革的目标是一致的,而中学生学习语言的根本目标与基础教育学会求知,学会做事,学会合作,学会做人的目标是一致的,真实新颖的选材对基础英语教学课程改革具有重要的反作用。时文报道就在文章中体现了这一要求。主要表现在以下几个方面:
1、反映海内外事件,文章结构严谨,内容贴近生活,用现代英语反映现代生活。
2、如果是新闻报道,都有比较固定的写作格式,如文首通常有报道的地点或时间,第一句话常常是文章的导语,有助于了解文章的大致内容和主题。
3、如果是新闻报道则是记叙文,有地点、时间、人物、事物等要素。
4、有许多大量反映当代社会变化的新词汇和表达方式。
5、命题既重细节,又重推理和主旨。
6、大背景中的小事件,大事件中的小插曲往往是选材的热点。
【应试对策】
1、在平时学习中,关注生活,阅读新闻报道和广告类文章、把阅读时事文章作为学习英语的重要途径。
2、了解新的词汇和表达方式。如:tsunami海啸,MP3players(MP3)播放器,well_offsociety小康社会等。
3、抓住文章主题,准确捕捉细节和内涵,进行合理的推理。
4、品味新闻的标题,联系平时所积累的知识,为了解材料大意作铺垫。
5、了解新闻报道的特殊规律,其内容和多含何人、何地、何事、何时等,阅读时要抓住新闻的这一主要特点去理解判断。
6、要注意文中以黑体、大写、下划线等方式加以提示的文字,因为这很有可能是材料的核心或至少是一部分内容的概括。
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