Unit I Life Science Text A Human Cloning Text B Are We 10 Years Away from Artificial Life? Unit 2 Biological Engineering Text A How Stem Cells Work? Text B Taking Your Genes in Hand Unit 3 New Energy Text A Ethanol, Schmethanol Text B The Coming Wave Unit 4 Transportation Text A Intelligent Highways Text B Making Waves Unit 5 New Facilities Text A Facial Recognition Systems Text B GPS——the Most Precise Navigation System Ever Invented Unit 6 Telecommunication Text A Video Conferencing Cell Phones Text B You Are Your Cell Phone Unit 7 Space Text A Starship Enterprise: the Next Generation Text B Phoenix to Go Digging on Red Planet Unit 8 Health and Medicine Text A Telemedicine Comes Home Text B Would a "Fat Tax" Save Lives? Unit 9 Internet Text A The Internet Is Sick... But We Can Make It Better Text B Watching While You Surf Unit 10 VR Technology Text A The Military Applications of Virtual Reality Text B Reality, Only Better Unit 11 Robots Text A Rise of the Rat-brained Robots Text B Nothing to Lose But Their Chains Unit 12 Environment Text A Future Crops. the Other Greenhouse Effect Text B The Methane Mystery Unit 13 Animals Text A Jellyfish Invasion Text B Who Belongs in the Zoo? Unit 14 Computer Science Text A Software That Makes Software Better Text B From Blueprint to Database Unit 15 Automobile Text A How Hydrogen-Boosted Gasoline Engine Works? Text B The Car Doctor Is In Glossary Acknowledgements
摘要
1 Sometimes you do things simply because you know how to do. People have known how tomake ethanol since the dawn of civilisation, if not before. Take some sugary liquid. Addyeast. Wait. They have also known for a thousand years how to get that ethanol out of theformerly sugary liquid and into a more or less pure form. You heat it up, catch the vapour thatemanates, and cool that vapour down until it liquefies. 2 The result burns. And when Henry Ford was experimenting with car engines a centuryago, he tried ethanol out as a fuel. But he rejected it——and for good reason. The amount ofheat you get from burning a litre of ethanol is a third less than that from a litre of petrol. Whatis more, it absorbs water from the atmosphere. Unless it is mixed with some other fuel, suchas petrol, the result is corrosion that can wreck an engine's seals in a couple of years. So whyis ethanol suddenly back in fashion？ That is the question many biotechnologists in Americahave recently asked themselves. 3 The obvious answer is that, being derived from plants, ethanol is "green". The carbondioxide produced by burning it was recently in the atmosphere. Putting that C02 back into theair can theerefore have no adverse effect on the climate. But although that is true, the realreason ethanol has become the preferred green substitute for petrol is that people know how tomake it——that, and the subsidies now available to America's maize farmers to produce thenecessary feedstock. Yet such things do not stop ethanol from being a lousy fuel. To solvethat, the biotechnologists argue, you need to make a better fuel that is equally green. This iswhat they are trying to do！ ……
