Putting Plants to Work

Using the power of the sun is nothing new. People have had solar-powered calculators and buildings with solar panels for decades. But plants are the real experts: They’ve been using sunlight as an energy source for billions of years.

Ceils in the green leaves of plants work like tiny factories to convert sunlight, carbon dioxide, and water into¹ sugars and starches, stored energy that the plants can use. This conversion process is called photosynthesis. Unfortunately, unless you’re a plant, it’s difficult and expensive to convert sunlight into storable energy. That’s why scientists are taking a closer look at exactly how plants do it.

Some scientists are trying to get plants, or biological cells that act like plants, to work as miniature photosynthetic power stations. For example, Mafia Ghirardi of the National Renewable Energy Laboratory in Golden, Colo.², is working with green algae³. She’s trying to trick them into producing hydrogen⁴ instead of sugars when they perform photosynthesis. Once the researchers can get the algae working efficiently, the hydrogen that they produce could be used to power fuel cells in cars or to generate electricity.

The algae are grown in narrow-necked glass bottles to produce hydrogen in the lab. During photosynthesis, plants normally make sugars or starches. “But under certain conditions, a lot of algae are able to use the sunlight energy not to store starch, but to make hydrogen,” Ghirardi says. For example, algae will produce hydrogen in an air free environment. It’s the oxygen in the air that prevents algae from making hydrogen most of the time.

Working in an air free environment, however, is difficult. It’s not a practical way to produce cheap energy. But Ghirardi and her colleagues have discovered that by removing a chemical called sulfate from the environment that the algae grow in, they will make hydrogen instead of sugars, even when air is present.

Unfortunately, removing the sulfate also makes the algae’s cells work very slowly, and not much hydrogen is produced. Still, the researchers see this as a first step in their goal to produce hydrogen efficiently from algae. With more work, they may be able to speed the cells" activity and produce larger quantities of hydrogen.

The researchers hope that algae will one day be an easy-to-use fuel source. The organisms are cheap to get and to feed, Ghirardi says, and they can grow almost anywhere: “You can grow them in a reactor, in a pond. You can grow them in the ocean. There’s a lot of flexibility in how you can use these organisms.”

词汇:

panel /5pAnl/ n.嵌板，发热板，仪器板  

starch /stB:tF/ n. 淀粉

miniature /5minjEtFE/ adj.口巧．微型的

sulfate /5sQlfeit/ n. 硫酸盐，硫酸酯

carbon dioxide 二氧化碳  

photosynthesis /7fEutEu5sinWEsis/ n. 光合作用

algae /5AldVi:/ n. 水藻，海藻  

注释:    

1. convert … into…：将……转换为 ……     

2. Colo.：Colorado，（美国科罗拉多州）的缩写形式  

3. Green algae: 绿藻       

Why do some scientists study how plants convert sunlight carbon dioxide, and water into sugars and starches?

A:Because they want algae to produce sugars and starches. B:Because they want green plants to become a new source of energy. C:Because they want to turn plant sugars to a new form of energy. D:Because they want to make photosynthesis more efficient.

Convert命令的作用是（）

A:可以将NTFS格式的文件系统在不损伤数据的情况下将其转换成FAT B:可以将NTFS格式的文件系统在数据轻微损伤的情况下，将其转换成FAT C:可以将FAT格式下的文件系统在不损伤数据的情况下将其转成NTFS D:可以将FAT格式下的文件系统在数据轻微损伤的情况下，将其转换成NTFS

命令“Convert”的目的是？（）

A:将FAT转换为FAT32 B:将FAT32转换为NTFS C:将NTFS转换为FAT32 D:将FAT32转换为FAT

Erroneous virtues are running out of control in our culture. I don’t know how many times my 13-year-old son has told me about classmates who received ＄10 for each "A" grade on their report cards—hinting that I should do the same for him should he ever receive an A. Whenever he approaches me on this subject, I give him the same reply: forget it! This is not to say that I would never praise my son for doing well in school. But my praise is not meant to reward or elicit future achievements, but rather to express my genuine delight in the satisfaction he feels at having done his best. Doling out ＄10 sends out the message that the feeling alone isn’t good enough.
As a society, we seem to be on the brink of losing our internal control—the ethical boundaries that guide our actions and feelings. Instead, these ethical standards have been eclipsed by external "stuff" as a measure of our worth. We pass this obscene message on to our children. We offer them money for learning how to convert fractions to decimals. Refreshments are given as a reward for reading. In fact, in one national reading program, a party awaits the entire class if each child reads a certain number of books within a four-month period. We call these things incentives, telling ourselves that if we can just reel them in and get them hooked, then the internal rewards will follow.
I recently saw a television program where unmarried, teenage mothers were featured as the participants in a program that offers a ＄10 a week "incentive" if these young women don’t get pregnant again. Isn’t the daily plight of being a single, teenaged mother enough to discourage them from becoming pregnant again No, it isn’t, because we as a society won’t allow it to be. Nothing is permitted to succeed or fail on its own merits anymore.
A staple diet of candy bars makes an ordinary apple or orange seem sour. Similarly, an endless parade of incentives corrodes our ability to feel a genuine sense of inner peace (or inner conflict). The simple virtues of honesty, kindness and integrity suffer from an image problem and are in desperate need of better publicity. One way to do this is by example. I fear that in our so-called upwardly mobile world we are on a downward spiral towards becoming morally bankrupt. We may soon render ourselves worthless inside, while desperately clinging to a shell of appearances.
According to the author, improper incentives include all the following EXCEPT ______.

A:money for learning how to convert fractions to decimals B:refreshments as a reward for reading. C:a party for the entire class for good behavior D:the internal rewards that follow

Erroneous virtues are running out of control in our culture. I don’t know how many times my 13-year-old son has told me about classmates who received ＄10 for each "A" grade on their report cards—hinting that I should do the same for him should he ever receive an A. Whenever he approaches me on this subject, I give him the same reply: forget it! This is not to say that I would never praise my son for doing well in school. But my praise is not meant to reward or elicit future achievements, but rather to express my genuine delight in the satisfaction he feels at having done his best. Doling out ＄10 sends out the message that the feeling alone isn’t good enough.
As a society, we seem to be on the brink of losing our internal control—the ethical boundaries that guide our actions and feelings. Instead, these ethical standards have been eclipsed by external "stuff" as a measure of our worth. We pass this obscene message on to our children. We offer them money for learning how to convert fractions to decimals. Refreshments are given as a reward for reading. In fact, in one national reading program, a party awaits the entire class if each child reads a certain number of books within a four-month period. We call these things incentives, telling ourselves that if we can just reel them in and get them hooked, then the internal rewards will follow.
I recently saw a television program where unmarried, teenage mothers were featured as the participants in a program that offers a ＄10 a week "incentive" if these young women don’t get pregnant again. Isn’t the daily plight of being a single, teenaged mother enough to discourage them from becoming pregnant again No, it isn’t, because we as a society won’t allow it to be. Nothing is permitted to succeed or fail on its own merits anymore.
A staple diet of candy bars makes an ordinary apple or orange seem sour. Similarly, an endless parade of incentives corrodes our ability to feel a genuine sense of inner peace (or inner conflict). The simple virtues of honesty, kindness and integrity suffer from an image problem and are in desperate need of better publicity. One way to do this is by example. I fear that in our so-called upwardly mobile world we are on a downward spiral towards becoming morally bankrupt. We may soon render ourselves worthless inside, while desperately clinging to a shell of appearances.

A:money for learning how to convert fractions to decimals B:refreshments as a reward for reading. C:a party for the entire class for good behavior D:the internal rewards that follow

Cheerleaders for renewable energy are fond of pointing out that patches of desert receive enough energy each year from sunlight to power the entire world. But few could explain how the construction of the millions of solar cells required to convert that energy into electricity would be financed. Public utility bosses and policymakers tend to dismiss wind and solar power as noble but expensive distractions, sustainable only through huge subsidies. But new studies suggest that renewables might not be as dear as skeptics suspect.
In a report that was due out on July 6th, Greenpeace, an environmental group, argues that public utilities would save money by investing in renewables. Windmills may cost more to build, the logic runs, but they do not require the purchase of fuel, unlike coal or gas-fired power plants. Those future fuel costs, Greenpeace says, massively outweigh the extra investment costs of renewables. If nuclear power were phased out and renewables’ share of electricity generation rose dramatically, it calculates the average annual savings between 2004 and 2030 would be $180 billion.
These figures, of course, rely on all sorts of questionable assumptions. In Greenpeace’s picture, the prices of gas and coal will rise, despite stagnating consumption of the former, and a steep drop in demand for the latter. It also helps that the future as Greenpeace sees it includes a big dose of energy efficiency, although its business-as-usual projections do not. Public utilities, at any rate, must not be making the same assumptions, since they continue to invest in power plants run on fossil fuels.
Other studies make a slightly less sweeping claim: that adding wind power to the electricity network can reduce the overall cost of electricity. The cost of producing wind power is almost nothing, since the fuel—wind—is free. So on a windy day, the cheapest power comes from wind turbines. That power, in turn, displaces electricity generation from sources with higher fuel costs, such as gas-fired plants. So power prices tend to fall when the wind is blowing. Nuon, a Dutch utility, calculates that in 2005 the average power price on the local spot market was over Euro 45 per megawatt hour when there was no wind, but under Euro 30 when the average wind-speed topped 13 metres per second.
Researchers in Denmark have gone a step further and put a value on this effect. They believe that wind power saved 1 billion kroner ($ 167m) off Danish electricity bills in 2005. On the other hand, Danish consumers also paid 1.4 billion kroner in subsidies for wind power. But this year, reckons Rune Moesgaard of the Danish Wind Industry Association, wind power will actually save consumers’ money for the first time, as the benefits resulting from lower power prices outweigh the falling cost of the subsidy.
According to the author, cheerleaders for renewable energy

A:are optimistic about the finance of the solar power construction. B:could hardly explain how solar cells convert sunlight into electricity. C:in general ignore the cost of the solar power construction. D:suspect that solar cells in desert are expensive.

If you made a list of all the jobs performed by the different kinds of energy, you would fill many pages.
Nuclear energy is used in some areas of the United States. But there are dangers. Waste materials from nuclear (51) would destroy life if they leaked (52) the land. When nuclear energy is produced, a lot of (53) is produced, too, so a flow of lake or ocean water is used to cool the operations. Then the water (54) to its source. If the returning water were too hot, it would destroy fish and other (55) .
Cow manure is being used to produce a kind of (56) . The manure from farms is put into a machine to convert it to a liquid. Then the gas is formed (57) a natural process. If the converter were not so (58) at the present time, it would be used in many places to provide (59) .
Garbage has become an energy source. It (60) to oil, steam, or electricity, or it is used on the land.
But recent (61) about power supplies has led to increased interest in the use of wind (62) a source of electrical power. Windmills are clean and they (63) no waste. And they use a (64) resource. Some scientists consider that wind energy systems can fulfill a valuable (65) in meeting the energy needs of industrialized nations and of the developing world.

A:converts B:is to convert C:is converting D:is converted

第一篇 　　Ear Breakthrough 　　New research published in the journal Current Biology has added significantly to understanding of how the ear works, giving hope to millions of deaf and hard of hearing people. 　　The latest research, conducted by Dr. Jorg T. Albet, a Deafness Research UK research fellow at the UCL Ear Institute, together with scientists at the University of Cologne, shows that fruit flies have ears which mechanically amplify sound signals in a remarkably similar way to the sensory(感觉的)cells found in the inner ear of vertebrates(脊椎动物)including humans. The finding means that the wealth of genetic techniques already available to study the fruit fly can now be used to target how the ear works. 　　Dr.Albert says."The biophysical parallels between the ways both fruit flies and humans convert sound into nerve signals are truly amazing.We may be allowed to hope that these mechanistic(机械学的)similarities extend further down to the genes and molecules that bring about hearing.But even if it finally should turn out that hearing in fruit flies relies on different molecules than does hearing in humans, the little fruit fly can help us find answers to some key questions of hearing research and –what is sometimes even more important -will surely help us ask the right questions." 　　The work is welcomed by Deafness Research UK, the country’s only medical research chanty for deaf people.Vivienne Michael, chief executive of Deafness Research UK.says," This is an important advance that paves the way toward a clear understanding of the genetics of deafness.The charily will continue to support culling-edge(尖端的)research through its Fellowship programme at the UCI.Ear institute and at other top research centres in the UK to achieve our goal of securing audical improvements in the prevention,diagnosis and treatment of all forms of hearing impairment" 　　There are nine million deaf and hard of hearing people in the UK and in most cases deafness results from loss of sensory cells in the inner ear known as "hair", cells.The cells can be images and lost through ageing, noise, genetic defects and certain drugs and, because the cells don’t regenerate, the result is progressive -and irreversible -hearing loss .Damage to these cells can also lead to tinnitus(耳鸣),which affects around five million people in the UK.Fruit files and humans share similarities in how they

A:ask and answer questions B:pass on their genes C:reproduce D:convert sound into nerve signals