Renewable energy, it turns out, does grow on trees. The fruit pods plucked from jatropha trees have seeds that produce clean-bur

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问题     Renewable energy, it turns out, does grow on trees. The fruit pods plucked from jatropha trees have seeds that produce clean-burning diesel fuel. But unlike corn and other biofuel sources, the jatropha doesn’t have to compete with food crops for arable land. Even in the worst of soils, it grows like weeds. Sound too good to be true? That’s why brothers Paul and Mark Dalton chose to name their Florida jatropha company My Dream Fuel.
    If President Barack Obama’s green-energy rhetoric is on the level, this should be the year the U. S. gets clued in to what much of the rest of the world is already betting: that jatropha, like other nonfood sources such as algae, will revive a biofuels movement battered of late by charges that it diverts too many crops from too many mouths. India has set aside 100 million acres for jatropha and expects the oil to account for 20% of its diesel consumption by 2011. Australia, China, Brazil and Kenya have also embraced it. In December, a Boeing 747 was successfully test-flown by Air New Zealand using a 50-50 blend of jatropha and aviation fuel.
    "This is a superior biodiesel, " says Roy Beckford, a University of Florida researcher and expert on sustainable farm development. He has been studying different varieties of jatropha and in February plans to publish his findings that trees like those the Daltons are growing (since 2006 they’ve planted 900,000 near Fort Myers) thrive so well in Florida that they may yield up to eight times as much oil as they do in places like India and Africa.
    Native to the Caribbean, jatropha curcas was taken to India in the 1600s by Portuguese sailors who used the seeds for long-burning lamp oil. When Paul Dalton, 54, a Washington attorney, decided to invest $ 500,000 in an alternative-fuel venture, he followed the Portuguese trail to India and found prolific new jatropha varieties being cloned in the city of Mysore. The fuel emits negligible greenhouse gases, and the trees can capture four tons of carbon dioxide per acre (which might make growers eligible for carbon credits on the global market). Says Ron Pernick, co-founder of the alternative-energy research firm Clean Edge, "Jatropha isn’t a silver bullet, but it looks very promising. "
    That’s good news not only for energy gluttons like the U. S. but also for energy-starved nations like Haiti, which rarely has enough diesel to power its capital for a full day. My Dream Fuel donates jatropha trees to Caribbean countries in the hope that they won’t have to choose between producing enough fuel and producing enough food. "We want to make money with jatropha, but we also want to make a difference, " Paul Dalton says. If jatropha can do both, it’s an idea that could grow like weeds.
Which of the following would be the best title for this text?

选项 A、A Different Kind of Renewable Energy: Jatropha
B、Jatropha: A Widely Planted Energy-producing Tree
C、Jatropha: The Next Big Biofuel?
D、Jatropha Can Also Produce Diesel Fuel

答案C

解析 主旨大意题。本文主要说明了麻风树作为一种新型的生物燃料的现实情况及其重大意义,所以标题必须能概括麻风树作为生物燃料的基本情况,也必须指出其重大意义。由此可知,选项[C]“麻风树——未来的重要生物燃料?”能比较恰当地概括原文的内容,所以[C]是答案。[A]“麻风树是一种不同的可再生资源”,这只是麻风树的一个特点而已,不能概括全文的内容,所以[A]不正确。[B]“麻风树是一种能产生能源的树.被广泛种植”,文章只提到少数几个国家对麻风树的重视情况.并不能由此推出该结论,此外它充其量也只是文章极小的一个细节,不能概括文章的大意,所以[B]不正确。[D]“麻风树同样能够生产柴油”,也是原文的细节内容,所以[D]也不选。
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