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Vocabulary for ielts part 10

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It is best to work through a unit from beginning to end as one exercise may revise the vocabulary from a previous exercise. The test practice sections provide further opportunities to extend your vocabulary, as well as giving you practice in the different sections of the IELTS test. | 16 The energy crisis It is not surprising then that many scientists and entrepreneurs are once again looking hard at the prospects for using algae to produce transportation fuels and sizeable amounts of money are being invested in various schemes for doing so. David Bayless a professor of mechanical engineering at Ohio University has been working with scientists to engineer a device that can grow cyanobacteria blue-green algae . It uses carbon dioxide from the gases emitted from power-plant chimneys and sunlight that is distributed to the growing surfaces through optical fibres. Bayless uses an enclosed bioreactor and claims to be able to produce as much as 60 grams of biomass per square metre of growing surface per day. Another recent effort is being carried out in San Diego by KentSeaTech Corporation. This company gained experience growing algae as a part of its aquaculture operations so was quick to respond when the California state government started looking for ways to treat the huge quantities of nutrient-laden water which runs off from adjacent farm lands. It s no real difficult feat to turn nutrients into algae says director of research Jon Van Olst but how do you get it out of the water This is what Van Olst and his co-workers have been trying to achieve. The people working on these ventures are clearly eager to make growing algae a commercial success. Yet it is not hard to find experts who view such prospects as dim indeed. John Benemann a private consultant in California has decades of experience in this area. He is particularly sceptical about attempts to make algae production more economical by using enclosed bioreactors rather than open ponds. He points out that Japan spent hundreds of millions of dollars on such research which never went anywhere. Even Van Olst has serious reservations. It may work he says but it is going to take a while and a lot of research before we get anywhere. Questions 1-5 Classify the following characteristics as belonging to