现代生活的方方面面都需要动力，而动力的来源——燃料则是我们当今社会发展所遇到的一大难题。今天我们的托福阅读材料中所介绍的蓝菌正是一种有可能在未来解决燃料问题的特殊细菌。 8 P. n, j% Y6 \3 R7 k+ F% E
When most people fill their gas tanks, they think of fossil fuels and pumping oil from the ground. But many scientists around the country think bacteria.$ x- V7 Q1 K0 u0 M$ v0 z
' l# l" j4 ?3 ]3 g Cyanobacteria
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Bacteria have a bad reputation because they are responsible for several human illnesses, but there are many thousands of species of bacteria.
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Some of the most interesting species are cyanobacteria which used to be called blue green algae because of their color. These bacteria are naturally found in bodies of water, and like plants, use sunlight to convert carbon dioxide into energy." Z4 m3 y, I) Y2 s; F: m( U
9 {4 x, ~3 S3 [; W Ethanol And Quantity
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Currently, we are using plants like corn to produce ethanol. It is a time consuming, expensive process that involves growing plants, transporting them, fermenting and processing them to get fuel. With bacteria, carbon dioxide can be converted directly into organic chemicals.
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2 q- K# ^& `0 C The only problem has been the quantity and type of fuels bacteria can produce.
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! \: \" s8 Y: Z, Q Biofuel Solutions* W2 g( T3 ~% W! D1 k" D5 N% G, ^' s2 v
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Scientists are tackling that dilemma…; k: |5 z* K3 L* ?7 n- }8 P% ?
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Some are developing strains that produce cellulose and sugars, and could produce the same amount of energy as corn using a fraction of the production energy and land area., j3 e2 ? y! ]; N
0 }6 N* N% w1 K( w& ^9 L' z- b Increasing Carbon Dioxide
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Others are splicing genes from other organisms into cyanobacteria to increase the amount of carbon dioxide fixing enzymes present in the cells. They have created strains that produce isobutyraldehyde gas that can be easily collected and converted into isobutanol.
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Advantages% p9 q8 ~7 V9 _9 w1 j; X
. j) ~3 `, n/ B* M- ^1 F, K Using bacteria to produce fuel is not only economical, it has two advantages. First, it recycles carbon dioxide which reduces greenhouse gas emissions. Secondly, it uses solar energy to convert carbon dioxide into liquid fuel. It is a win win situation. ~' Z0 p+ \9 k# L6 E; p4 r
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In the future, there may be no need to worry about petroleum dependency or oil spills. Drivers will pull up to the pump and fill up on Cyanogas, the green alternative.
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! s3 m! E' O0 A% Q9 Z h Notes
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1. Cyanobacteria：蓝菌，又称蓝细菌、蓝绿菌、蓝藻或蓝绿藻，或称为蓝菌门，当中包括发菜、螺旋藻等生物。虽然传统上归于藻类，但近期发现因为没有细胞核等等，与细菌非常接近，因此现时已被归入细菌域。蓝菌在地球上已存在约30亿年，是目前以来发现到的最早的光合放氧生物，对地球表面从无氧的大气环境变为有氧环境起了巨大的作用。3 y* i9 h6 B+ ~
/ I3 {' J* a0 d 2.Algae：very simple plants with no true stems or leaves, found chiefly in water 藻; 藻类.
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# L# n1 d' C( q. O" r s 3.Ethanol：another name for alcohol，乙醇，酒精。: E8 q: ? g) s1 f( n- f
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4.Ferment: (make sth) change chemically through the action of organic substances (esp yeast) (使某物)发酵:
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Fruit juices ferment if they are kept a long time.果汁放置日久会发酵.( }5 o" p$ Y* U* y! K( G
4 P* V' i6 B9 }- b* c( j When wine is fermented it gives off bubbles of gas.酒发酵时会放出气泡. |
发表于 2012-8-14 23:21:39
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