文档内容
科技环保类
即刻题库 www.jike.vip
1 、 英译汉
The laptop computer is a small, portable computer that’s light and small
enough to hold on your lap. It is smaller than a luggage but larger than a notebook
computer. A laptop usually weighs between 8 and 14 pounds, and when folded shut
is about the size of a small briefcase. Laptops can be plugged in or run on batteries,
although the batteries must be recharged every few hours. Laptop computers use a
thin, light weight display screen called a flat-panel display, rather than the cathode
ray tube technology of larger personal computers. Laptop displays vary widely in
quality. Typically, their display screens show fewer lines than displays on larger
computers and can be difficult to read in bright light. Laptops are self-contained
units, having their own CPUs, memory, and disk drives. While more expensive than a
desktop computer with equivalent computing power, a laptop can be ideal for the on-
the-go user who needs a second, portable computer. Laptops aren’t always a
suitable replacement for desktop computer, since they can’t be expanded or
modified easily should your computing needs change. Also, the display is inferior to
standard video graphics array（VGA）displays, although active matrix displays
compete well except for size.
2 、 英译汉
At first, as he adjusted pumps and checked temperatures, Aaron Boucher looked
like any technician in the control room of an electrical plant. Then he rushed to the
window and scanned the sky, to check his fuel supply.
Mr. Boucher was battling clouds, timing the operations of his power plant to get
the most out of patchy sunshine. It is a skill that may soon be in greater demand, for
the world appears to be on the verge of a boom in a little-known but promising type
of solar power.
It is not the kind that features shiny panels bolted to the roofs of houses. This
type involves covering acres of desert with mirrors that focus intense sunlight on a
fluid, heating it enough to make steam. The steam turns a turbine and generates
electricity.
The technology is not new, but it is suddenly in high demand. As prices rise for
fossil fuels and worries grow about their contribution to global warming, solar
thermal plants are being viewed as a renewable power source with huge potential.
After a decade of no activity, two prototype solar thermal plants were recentlyopened in the United States, with a capacity that could power several big hotels, neon
included, on the Las Vegas Strip, about 20 miles north of here. Another 10 power
plants are in advanced planning in California, Arizona and Nevada.
On sunny afternoons, those 10 plants would produce as much electricity as three
nuclear reactors, but they can be built in as little as two years, compared with a
decade or longer for a nuclear plant. Some of the new plants will feature systems that
allow them to store heat and generate electricity for hours after sunset.
At Nevada Solar One the other day, Mr. Boucher, 30, ran the computerized
control room. He was trying to produce as much electricity as possible while saving
heat to tide the plant over as clouds cast episodic shadows on the solar array. “I’ve
been fighting it all day,” he said.
Imperceptibly, in the dusty wind of the high desert, 182,000 mirrors moved from
east to west, tracking the sun across the sky.
3 、 英译汉
When people argue about whether coffee is good for health, they're usually
thinking of the health of the coffee drinker. Is it food for your heart? Does it increase
blood pressure? Does it help you concentrate? However, coffee affects the health of
the human population in other ways, too.
Traditionally, coffee bushes were planted under the canopy (树冠) of taller
indigenous (土生土长的) trees. However, more and more farmers in Latin America are
deforesting the land to grow full-sun coffees. At first, this increases production
because more coffee bushes can be planted if there aren’t any trees. With
increased production come increased profits.
Unfortunately, deforesting for coffee production immediately decreases local-
wildlife habitat. Native birds nest and hide from predators (捕食者) in the tall trees
and migrating birds rest there.
Furthermore, in the long term, the full-sun method also damages the ecosystem
because more chemical fertilizers and pesticides are needed to grow the coffee. The
fertilizers and pesticides kill insects that eat coffee plant, but then the birds eat the
poisoned insects and also die. The chemicals kill or sicken other animals as well, and
can even enter the water that people will eventually drink.
Fortunately, farmers in Central and South America are beginning to grow more
coffee bushes in the shade. We can support these farmers by buying coffee with such
labels as "shade grown" and "bird friendly." Sure, these varieties might cost a little
more. But we're paying for the health of the birds, the land, ourselves, and the
planet. I think it's worth it.
4 、 英译汉
Fiber-optic lines will form most of the backbone of the information highway, just
as they do for the phone system today. Fiber-optic cable is made of long, thin strands
of glass rather than wire, and it transmits information in the form of digitized pulses
of laser light rather than the radio waves used by coaxial cable. Because light pulses
have shorter wavelengths than radio waves, engineers can cram much more data
into fiber-optic lines than into other kinds of cables and wires. A single fiber, forexample, can handle a mind-boggling 5,000 video signals or more than 500,000 voice
conversations simultaneously. This huge capacity allows it to transmit all signals
digitally. So noise or static easily can be filtered out. Finally, because glass is an
inherently more efficient medium for transmitting information than other materials,
a fiber-optic line can transmit a signal thousands of miles without much “signal
loss”. Fiber-optic cable, simply put, is the method of choice for transmitting massive
quantities of information over long distances.
Another key is “digital compression”—a variety of methods for reducing the
amount of digital code (streams of ones and zeros) needed to represent a piece of
information—whether it is a document, a still picture, a movie or a sound. Digital
compression is most critical for transmitting video, because digitized video consumes
enormous amounts of space. Just four seconds of a digitized film, for example, would
completely fill a 100-megabyte hard drive. A feature film of typical length, if
uncompressed, would occupy more than 350 ordinary compact discs.
Compression techniques achieve their gins by recording only the changes from
one frame to the next, The background image in a movie scene, for example, typically
does not change much from one flame to another. In a digital compression scheme,
the background would be recorded only once; after that, only the actors’
movements would be captured.
One result is more choices—hundreds of channels coming through your cable TV
line instead of dozens. Digital compression also makes it easier to piggyback data
onto media that were not designed with data in mind: in particular, phone lines.
5 、 英译汉
The National Trust in Britain plays an increasingly important part in the
preservation for public enjoyment of the best that is left unspoiled of the British
countryside. Although the Trust has received practical and moral support from the
Government, it is not a rich government department. It is a voluntary association of
people who care for the unspoiled countryside and historic buildings of Britain. It is a
charity which depends for its existence on voluntary support from members of the
public. Its primary duty is to protect places of great natural beauty and places of
historical interest.
The attention of the public was first drawn to the dangers threatening the great
old houses and castles of Britain by the death of Lord Lothian, who left his great
seventeenth-century house to the Trust together with the 4500 acre park and estate
surrounding it. This gift attracted wide publicity and started the Trust’s “Country
House Scheme”. Under this scheme, with the help of the Government and the
general public, the Trust has been able to save and make accessible to the public
about 150 of these old houses. Last year, about 1.75 million people paid to visit these
historic houses, usually at a very small charge.
In addition to country houses and open spaces, the Trust now owns some
examples of ancient wind and water mills, nature reserves, 540 farms and nearly
2500 cottages or small village houses, as well as some complete villages. In these
villages no one is allowed to build, develop or disturb the old village environment in
any way and all the houses are maintained in their original 16th century style.
Over4000 acres of coastline, woodland, and hill country are protected by the Trust
and no development or disturbances of any kind are permitted. The public has free
access to these areas and is only asked to respect the peace, beauty and wildlife.Over the past 80 years the Trust has become a big and important organization
and an essential and respected part of national life. It helps to preserve all that is of
great natural beauty and of historical significance not only for future generations of
Britons but also for the millions of tourists who each year invade Britain in search of
a great historic and cultural heritage.
6 、 英译汉
Are you a real grump (脾气坏的人) in the mornings? Do you wake up every day
feeling tired, angry and upset, and all too ready to flit the snooze (瞌睡) button? If so,
then a new alarm clock could be just for you.
The clock, called SleepSmart, measures your sleep cycle, and waits for you to be
in your lightest phase of sleep before waking you up, Its makers say that should
ensure you wake up feeling refreshed (恢复精力) every morning.
As you sleep you pass through a sequence of sleep states—light sleep, deep
sleep and REM sleep (快速眼动睡眼)—that repeats approximately every 90 minutes.
The points in that cycle at which you wake can affect how you feel later, and may
even have a greater impact than how long or little you have slept. Being wakened
during a light phase means you are more likely to wake up cheerful and full of life
and interest.
SleepSmart records the distinct pattern of brain waves produced during each
phase of sleep, via a headband equipped with electrodes (电极) and a
microprocessor. This measures electric activity of the wearer’s brain, and
communicates wirelessly with a clock unit near the bed. You program the clock with
the latest time at which you want to be wakened, and it then at the proper time
wakes you during the last light sleep phase before that.
The concept was invented by a group of students at Brown University in Rhode
Island after a friend complained of waking up tired and performing poorly on a test.
“As sleep-deprived (剥夺) people ourselves, we started thinking of what to do about
it,” says Eric Shashoua, a recent college graduate and now chief executive officer of
Axon Sleep Research Laboratories, a company created by the students to develop
their idea. They have almost finished a prototype and plan to market the product by
next year.
7 、 英译汉
Glaciers in Antarctica are melting faster and across a much wider area than
previously thought, a development that threatens to raise sea levels worldwide and
force millions of people to flee low-lying areas. Researchers once believed that the
melting was limited to the Antarctic Peninsula, a narrow tongue of land pointing
toward South America. But satellite data and automated weather stations now
indicate it is more widespread. The melting also extends all the way down to what is
called west Antarctica. By the end of the century, the accelerated melting could cause
sea levels to climb by 3 to 5 feet-levels substantially higher than predicted by a major
scientific group just two years ago. Making matters worse, the ice shelves that hold
the glaciers back from the sea are also weakening.
For years, the continent at the bottom of the world seemed to be the only placeon the planet not experiencing climate change. Previous research indicated that
temperatures across much of Antarctica were staying the same or slightly cooling.
The big surprise was exactly how much glaciers are melting in western Antarctica, a
vast land mass on the Pacific Ocean side of the continent that is next to the South
Pole and includes the Antarctic Peninsula. The glaciers are slipping into the sea faster
because the floating ice shelf that would normally stop them—usually 650 t0980 feet
thick—is melting. And the glaciers' discharge is making a significant contribution to
increasing sea levels.
Together, all the glaciers in west Antarctica are losing a total of around 114
billion tons per year because the melting is much greater than the new snowfall.
That's equivalent to the current mass loss from the whole of the Greenland ice sheet,
New research found that melting glaciers will add at least 7 inches to the world's sea
level—and that's if carbon dioxide pollution is quickly capped and then reduced.
8 、 英译汉
The problem of pollution is also of great social concern. Continued population
increase, accompanied by a rise in the level of living standards, not only threatens to
exhaust American resources but pollutes the environment to such an extent that
production in the thickly settled area is impossible without damaging the health of
the local residents.
Smog, once an urban annoyance, is now recognized as a health risk, and the
automobile has been pinpointed as the principal culprit. Heavy industries have been
blamed for river, soil, air, noise and visual pollutions. DDT and other chemical
remedies have been doing more ecological harm than the good that they may have
brought along.
Several decades ago, Americans dumped raw sewage into rivers and many
industrial plants are now still dumping chemical pollutants into lakes, rivers and
oceans. Oceans used to be and are still being considered to be a reserve of seafood.
Today, after the oceans have become the home of all pollutants, this use of the
oceans is being reduced at an alarming rate.
The worst pollution threat is concentrated in and near large cities. There the
people-made pollutants increasingly surpass the ability of air and water to dilute (冲
淡；稀释) the contaminants (污染物) to safe levels. The natural ecological cycle
depends on plants, which absorb some pollutants and release oxygen to the air. But
near large cities, natural vegetation becomes scarce, and introduced trees,
ornamental shrubs and gardens are far from adequate in absorbing motor vehicle
and industrial air pollutants. Finally, some pollutants, most notably atomic waste,
may continue to contaminate air, land, and water for thousands of years. Therefore,
ecocrisis—ecocatastrophe or ecocide—has been for some time one of the major
concerns of not only the ecoactivists and environmentalists, but of many scientists of
other fields and the government authorities of many countries as well.
