题目内容
（请给出正确答案）
A. traditional lighting is less durable and dearer
B. a laser excited the quantum dots
C. America adopted LEDS
D. graduate students work hard
E. quantum dot mixtures are magic
F. it is more efficient
Unlike traditional lighting, LEDs do not give out heat so ______.
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更多“A. traditional lighting is less durable and dearerB. a laser excited the quantum dotsC. Am”相关的问题
What’S the main idea of the passage7
A．Laser light treatment of heart disease should take the place of the traditional operatlon．
B．Laser light treatment has been proved better and more effective than the traditional operation．
C．More advanced technology should be encouraged to try on．
D．Laser light treatment of heart disease still needs’more research．
LED Lighting
1 An accidental discovery announced recently has taken LED lighting to a new level, suggesting it could soon offer a cheaper, longer-lasting alternative to the traditional light bulb. The breakthrough adds to a growing trend that is likely to eventually make Thomas Edison&39;s bright invention obsolete. LEDs are already used in traffic lights, flashlights, and architectural lighting. They are flexible and operate less expensively than traditional lighting.
2 Michael Bowers, a graduate student2 at Vanderbilt University, was just trying to make really small quantum dots, which are crystals generally only a few nanometers big. Quantum dots contain anywhere from 100 to 1,000 electrons. They&39;re easily excited bundles of energy, and the smaller they are, the more excited they get. Each dot in Bowers&39; particular batch was exceptionally small, containing only 33 or 34 pairs of atoms.
3 When you shine a light on quantum dots or apply electricity to them, they react by producing their own light, normally a bright, vibrant color. But when Bowers shined a laser on his batch of dots, something unexpected happened. He was surprised when a white glow covered the table. The quantum dots were supposed to emit blue light, but instead they were giving off a beautiful white glow.
4 Then Bowers and another student got the idea to stir the dots into polyurethane and coat a blue LED light bulb with the mix. The lumpy bulb wasn&39;t pretty, but it produced white light similar to a regular light bulb.
5 LEDs produce twice as much light as a regular 60 watt bulb and burn for over 50,000 hours. The Department of Energy estimates LED lighting could reduce U. S. energy consumption for lighting by 29 percent by 2025. LEDs don&39;t emit heat, so they&39;re also more energy efficient. And they&39;re much harder to break.
6 Quantum dot mixtures could be painted on just about anything and electrically excited to produce a rainbow of colors, including white. The main light source of the future will almost surely not be a bulb. It might be a table, a wall, or even a fork.
Paragraph 1 ______
A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy
Paragraph 3 ______
A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy
Paragraph 5 ______
A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy
Paragraph 6 ______
A LED Lighting Is Not MatureB LED Lighting Will Replace Traditional LightingC Almost Everything Could Be the Main Light Source in the FutureD LED Lighting Has Many AdvantagesE Bowers Made an Unexpected DiscoveryF LED Light Bulbs Look Lumpy
Unlike traditional lighting, LEDs do not give out heat so ______.
A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient
Edison&39;s bright invention is likely to be outdated because ______.
A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient
Something unexpected happened during Bower&39;s experiment when ______.
A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient
Over one quarter of energy consumption for lighting could be saved by 2025 if ______.
A traditional lighting is less durable and dearerB a laser excited the quantum dotsC America adopted LEDsD graduate students work hardE quantum dot mixtures are magicF it is more efficient
请帮忙给出每个问题的正确答案和分析，谢谢！
听力原文： Since the 1960s, the English diet has become more diverse; the English now eat a wide variety of European and Asian foods. Many traditional foods such as beef and potatoes have given way to poultry and pasta (面食) dishes. Fast food bas also become more available, and hamburger restaurants now rival the traditional fish-and-chip shops in popularity. Numerous Chinese and Indian restaurants and pizza houses provide take-away service, and many pubs serve anything from snacks to fun meals as well as alcoholic beverages. Traditional English dishes include roost beef and Yorkshire pudding and steak and kidney pie.
The English generally eat three meals a day. A traditional English breakfast consists of any or all of the following: bacon, sausages, grilled (烤炙的) or fried tomatoes, mushrooms, eggs, or toast. Black pudding (blood pudding) may also appear on the menu. However, fewer people now eat a cooked breakfast on a regular basis, preferring various combinations of carnal, toast, juice or fruit, and tea or coffee. The midday meal is usually referred to as lunch and the evening meal as dinner or, when it is less formal, as supper. Working-class people tend to call the midday meal dinner and the meal they have in the early evening "tea." The tradition of afternoon tea, when tea, biscuits, and cakes are enjoyed at about 4 pm, has declined. Similarly, many people no longer have more than a light lunch or snack in the middle of the day.
(26)
A．Beef and potatoes.
B．European and Asian foods.
C．Roast beef and Yorkshire pudding.
D．Steak and kidney pie.
Traditional estimates have failed to track the fall in the price of light, especially over the past 200 years. As a result, they overstate today's price, relative to the price in 1800, not by a few percentage points, nor even by a factor of one or two, but by a factor of about 1000. Even by the standards of economics, that is a large error. The implications are of corresponding size. If the prices of other things are measured as badly as the price of light, it follows that traditional estimates of economic growth are way off the mark.
Economists are familiar with the difficulty of measuring changes in prices over time. It seems easy to measure the price of, say, a ball-point pen. But suppose that. a new version comes along that costs twice as much and lasts four times as long. If it catches on, the price of a pen has doubled—but the price of pen-services, as it were, has halved. This second price is the one that should be used to calculate the change in living standards. However, it is often difficult to observe. You need to know not just the change in the prices of the goods but also the change in the services that the goods provide. Measuring that is especially hard when the range of services itself changes over time. (Compare the communication-services provided by a modern telephone with those of one from the 1950s, for instance.)
Mr. Nordhaus points out that light has a useful property in this respect. Its service— illumination—does not vary. Babylonians used lamps for much the same reason that modern Americans use incandescent bulbs. With diligence and great ingenuity, Mr. Nordhaus has collected data on the light-services provided down the ages by: burning sticks; fat-and-oil- burning lamps; candles (tallow, sperm-oil, etc); gas lights (various); kerosene lamps; and the many different kinds of electric light. (The unit of measurement is the lumen; a wax candle emits about 13 lumens, a modern 100-watt bulb on 110 bolts about 1,200.) Mr. Nordhaus has also collected data on the prices of these sources of light: the price of a candle, the price of a given quantity of gas or electricity, and so on.
Putting the two together yields a true measure for the price of light. In nominal terms, the price of 1,000 lumen-hours has fallen from about 40 cents in 1800 to about one-tenth of a cent today. The black line in the chart plots this series as an index. (The sharp fall at the end of the line marks the introduction of the compact fluorescent bulb.) In real terms, of course, the fall is even sharper: 40 cents in 1800 is worth more than $4 in today's money. Compare this with a price series calculated using the conventional methods of official statistics—that is, by looking at the prices of goods that provide light rather than at the price of light itself. Mr. Nordhaus stitches together such a series from a variety of official sources. According to this measure, the price of light has fallen in real terms since 1800, but has gone up by 180% in nominal terms (as shown by the white line in the chart). In other words, conventional estimates would put the price of light in 1800 at about four-hundredths of a cent per 1,000 lumen-hour. Mr. Nordhaus' first series shows that the price of light in 1800 was about 1,000 times dearer than that.
This staggering difference is par@ an illustration of the effect of compound interest. It represents a drift of roughly 3.6% a year between the official and the t
Solar Power without Solar Cells
A dramatic and surprising magneticeffect of light discovered by University of Michigan1researcherscould lead to solar power without traditional semiconductor-based solar cells.The researchers found a way to make an“optical51 ,” said Stephen Rand, a professor in thedepartments of Electrical Engineering and Computer Science, Physics and AppliedPhysics.
Light has electric and magnetic52 .Until now, scientists thought the effect of the magnetic field were so weakthat they could be 53 . What Rand and his colleagues found isthat at the right intensity, when light is traveling through a material thatdoes not 54 electricity, the light field cangenerate magnetic effects that
are 100 million times stronger than previouslyexpected. Under these circumstances, the magnetic effects develop strength55 toa strong electric effect.
“This could lead to a new kind of solarcell without semiconductors and without absorption to produce charge separation,” Rand said. “In solar cells, the 56 goesinto a material, gets absorbed and creates heat. Here, we expect to have a verylow heat load2. Instead of the light being absorbed, energy is stored in themagnetic moment3. Intense magnetization can be induced by intense light andthen it is ultimately capable of providing a capacitive power 57 Whatmakes this possible is a previously undetected brand of “opticalrectification,” says William Fisher, a doctoral student in applied physics. Intraditional optical rectification, light's electric field causes a chargeseparation, or a pulling58of the positive and negative charges ina material. This sets up a voltage, similar to59in a battery.
Rand and Fisher found that under the rightcircumstances and in right types of materials, the light's magnetic field canalso create optical rectification. The light must be shone througha 60 thatdoes not conduct electricity, such as glass. And it must be focused to anintensity of 10 million watts per square centimeter8. Sunlight isn't this61 onits own, but new materials are being sought that would work at lowerintensities, Fisher said.
“In our most recent paper, we show thatincoherent light9 like sunlight is theoretically almost62effectivein producing charge separation as laser light is,” Fisher said.
This new63 couldmake solar power cheaper, the researchers say. They predict that with improvedmaterials they could achieve 10 percent efficiency in converting solar power touseable energy. That's equivalent to today's commercial-grade solar cells.
“To manufacture modem solar cells, youhave to do64 semiconductor processing,” Fisher said.“All we would need are lenses to focus the light and a fiber to guide it. Glassworks for65 .It's already made in bulk, and itdoesn't require as much processing. Transparent ceramics might be even better.”
51.A.disc
B.fiber
C.instrument
D.battery
Shows and Performances
LAZER VAUDEVILLE
This exciting new act combines high-tech laser magic with the traditional arts of vaudeville. Complete with superlative juggling, black light illusion, acrobatics, zany comedy, and audience participation!
Performing in the Forum at 7:30, 8:30, 9:30 &10:30.
Sponsored by The NYSEG Foundation.
CENTRAL PARK STOMPERS
Live from NYC! This jumping' jiving' group of six sensational and talented musicians is the perfect blend of 1940s nostalgia, rock and roll, and high-octane energy. The Stompers high-energy show conveys a magnetic and infections vibration that will keep you dancing all night long! Performances at 7: 30, 8: 30,
9:30 & 10:30 in the First Presbyterian Church Sanctuary.
Sponsored by The Oakdale Mall.
ILLUMINATED MEMORIES — MANDALA OF LIGHT
The plaza area in front of the NY State Office Building will glow with the light of thousands of votive candles. Ask a First Night volunteer to give you one to place in the section of your choice.
Sponsored by: YESCAP, a Partnership with Lourdes & Senator Libous.
ROOSEVELT DEAN & THE SPELLBINDERS
Straight from the Dinosaur Bar-B-Que in Syracuse, Dean & his crew cook up a menu of succulent deep delta blues and R & B fare. Dean keeps his fans shaking on the dance floor so come inside and get HOT!
Roosevelt performs at 6: 30, 8:00 & 10:30 in the Arena.
Sponsored by Roadrunner.
NICKELODEON — THE BIG HELP
Nickelodeon and First Night invite you and your family to "Big Helpers in Action." This interactive stage show combines Nickelodean style. games and stunts while encouraging kids to make a difference through volunteering. Don't worry though, someone will still get slimed! Shows at 7:00 &9:30 in the Arena. Sponsored by Road Runner and Time Warner Cable.
Which of the following activities is sponsored by Road Runner and Time Warner Cable according to the passage？
A．NICKELODEON — THE BIG HELP.
B．CENTRAL PARK STOMPERS.
C．ILLUMINATED MEMORIES — MANDALA OF LIGHT.
D．ROOSEVELT DEAN & THE SPELLBINDERS.
Kite
Kite flying is the sport of sending up into the air, by means of the wind, a light frame. covered with paper, plastic or doth. The frame. can be one of many different shapes and is attached to a long string held in the hand or wound on a drum. Kites have a long history practical application and many different types of kite have been developed to serve various purposes.
The ancient Chinese used bird-kites to carry ropes across rivers and valleys. The current folding kite which will dive excitingly is an improved type of such a kite. With its long flat body and single pair of bird like wings, it looks just like a large bird in the air. The modern version is usually made of tissue paper rather than the traditional silk.
Man-lifting kites were developed in ancient times, again by the Chinese, for getting information from walled cities and army camps. In fact, as recently as World War Ⅱ, German U-boats flew kites from their towers to lift people into the air to watch the land. These kites, which are no longer in existence, were made of lightweight cloth. They were much larger and stronger than the Chinese ones. Their design, however, was simply that of the cutter kite. Smaller in size, this type of kite is still very popular as a toy for children, being easy to make with a diamond-shaped frame, no wings and brown-paper covering.
Box kites are another type of kite found in toy shops today. The first box kite, named for its box-like body, was developed in the 19th century to test theories of flight and this type of cotton-covered kite greatly assisted the success of early airplanes. These kites are the ancestors of a heavier version of the box kite, called the double box kite, which consists of two main sections, placed side by side. Developed for the peacetime purpose of fishing in strong sea wind, it is the only modern kite described which has practical value. A long-lasting plastic material has to be used for this kite, which carries fishing lines.
The ancient Chinese bird-kites were usually made of light frames covered with ______.
A．silk
B．paper
C．cloth
D．plastic
Digital Camera
In the past twenty years, most of the major technological breakthroughs in consumer electronics have really been part of one larger breakthrough. Whet, you get down to it, CDs, DVDs, HDTV, MP3s and DVRs are all built around the same basic process: convening conventional similar information(represented by a fluctuating wave) into digital information (represented by ones and zeros, or bits). This fundamental shift in technology totally changed how we handle visual and audio information—it completely redefined what is possible.
The digital camera is one of the most remarkable instances of this shift because it is so truly different from its ancestor. Conventional cameras depend entirely on chemical and mechanical processes, you don't even need electricity to operate them. On the other hand, all digital cameras have a built-in computer, and all of them record images electronically.
The new approach has been enormously successful. Since film still provides better picture quality, digital cameras have not completely replaced conventional cameras. But, as digital imaging technology has improved, digital cameras have rapidly become more popular.
Understanding the Basics
To get a digital image, you need the image to be represented in the language that computers recognize—bits and bytes. Essentially, a digital image is just a long string of 1s and 0s that represent all the tiny colored dots—or pixels(像素)—that collectively make up the image.
If you want to get a picture into this form, you have two options:
You can take a photograph using a conventional film camera, process the film chemically, print it onto photographic paper and then use a digital scanner to sample the print(record the pattern of light as a series of pixel values).
At its most basic level, this is all there is to a digital camera. Just like a conventional camera, it has a series of lenses that focus light to create an image of a scene. But instead of focusing this light onto a piece of film, it focuses it onto a semiconductor device that records light electronically. A computer then breaks this electronic information down into digital data.
A Filmless Camera
Instead of film, a digital camera bas a sensor that converts light into electrical charges. The image sensor employed by most digital cameras is a charge coupled device(CCD). Some cameras use complementary metal oxide semiconductor(CMOS) technology instead. Both CCD and CMOS image sensors convert light into electrons. A simplified way to think about these sensors is to think of a 2-D array of thousands or millions of tiny solar cells.
Once the sensor converts the light into electrons, it reads the value(accumulated charge) of each cell in the image. This is where the differences between the two main sensor types kick in:
A CCD transports the charge across the chip and reads it at one corner of the array. An analog-to-digital converter(ADC) then turns each pixel's value into a digital value by measuring the amount of charge at each photosite and converting that measurement to binary(二进制) form.
CMOS devices use several transistors at each pixel to enlarge and move the charge using more traditional wires. The CMOS signal is digital, so it needs no ADC.
Capturing Color
Unfortunately, each photosite is colorblind. It only keeps track of the total intensity of the light that strikes its surface. In order to get a full color image, most sensors use filtering to look at the light in its three primary colors. Once the camera records all three colors, it combines them to create the full spectrum(光谱).
There are several ways of recording the three colors in a digital camera. The highest quality cameras use three separate sensors, each with a different filter. Another meth
A．Y
B．N
C．NG
Many animals engage in play，but homo sapiens is the only animal (1) have invented sports.Since sports are an invention，a part of culture (2) than an aspect of nature，all definitions of sports are somewhat arbitrary. (3) sports are a human universal found in every known culture or a (4) unique to modern society depends upon one's definition of sports.Men and (5) have always run，jumped，climbed，lifted，thrown， and wrestled，but they have (6) always performed these physical activities competitively. Although all literate societies seem to (7) contests of one sort or another in which men， and sometimes women， (8) in displays and tests of physical skill and prowess，sports may be (9) defined as physical contests performed for their own sake and not for (10) ulterior end.According to this strict definition，neither Neolithic hunters nor contestants (11) religious ceremonies such as the ancient Olympic Games were engaged in sports. (12) on the stipulation that sports must be performed for their own sake (13) the paradoxical elimination of many activities which are usually thought of as (14) ，such as exercises done for the sake of cardiovascular fitness，races run (15) satisfy a physical education requirement，ball games played to earn a paycheck. (16) definition also means abandonment of the traditional usage in which"sport，"derived (17) Middle English disporter，refers to any light hearted recreational activity.In the. (18) of some 18th- century aristocrats，a game of backgammon and the seduction of (19) milkmaid were both considered good sport，but this usage of the term (20) become archaic.
(1)
What is the meaning of“folklore”in the last paragraph？
A. Traditional customs and beliefs.
B. Verified hypotheses.
C. Widely held unsupported notions.
D. Tales or sayings preserved orally.
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