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"s bright invention1 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 electrons3. They"re easily excited bundles of energy, and the smaller they are, the more excited they get. Each dot in Bowers" 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 light4, 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"t pretty, but it produced white light singular to a regular light bulb.

5 LEDs produce twice as much light as a regular 60 watt bulb and bum 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"t emit heat, so they"re also more energy efficient. And they"re much harder to break.

6 Quantum dot mixtures could be painted on just about anything5 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.

 

词汇: 

LED / ,eli:’di: / = light-emitting diode发光二极管

obsolete / ’ɒbsəli:t/ adj过时的,被淘汰的

flashlight / ’flæʃlaɪt/ n手电筒

architectural / ,ɑ:kɪ’tektʃərəl / adj建筑的

quantum / ’kwɒntəm / n量子

crystal / ’krɪstl / n晶体

batch / bætʃ/ n一批

vibrant / ’vaɪbrənt /adj(颜色)鲜明的

polyurethane / ,pɒlɪ’jʊərəθeɪn, -æn / n聚亚安酯

lumpy / ’lʌmpɪ/ adj粗糙的

 

注释:

1bright invention:聪明的发明

2graduate student:研究生

3Quantum dots contain anywhere from 100 to 1,000 electrons:量子点含1001000个电子不等。anywhere(限定范围内的)任何一点。又如:

His monthly salary is anywhere between 3,000 yuan to 5,000 yuan.

他的月工资在30005000元之间。

4The quantum dots were supposed to emit blue light:按常规,量子点会发出蓝色光。be supposed to被期望(按规则、惯例)做某事。又如:

They were supposed to have finished writing the report three days ago.

他们三天前就该写完那份报告。

5just about anything:几乎任何东西。about = almostA 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 ________.

A:A B:B C:C D:D E:E F:F

Why So Many Children

    In many of the developing countries in Africa and Asia, the population is growing fast . The reason for this is simple : Women in these countries have a high birth rate — from 3.0 to 7.0 children per woman . The majority of these women are poor , without the food or resources to care for their families ? The answer may be that they often have no choice . There are several reasons for this .

    One reason is economic . In a traditional agricultural economy , large families are helpful .Having more children means having more workers in the fields and someone to take care of the parents in old age 1. In an industrial economy, the situation is different. Many children , do not help a family; instead, they are an expense. Thus, industrialization has generally brought down the birth rate. This was the case inItaly, which was industrialized quite recently and rapidly. In the early part of the twentieth century,Italywas a poor, largely agricultural country with a high birth rate. After World War,Italy"s economy was rapidly modernized and industrialized. By the end of the century, the birth rate had dropped to 1. 3 children per woman, the world"s lowest.

    However, the economy is not the only important factor that influences birth rate.Saudi Arabia, for example, does not have an agriculture-based economy, and it has one of the highest per capita incomes in the world. Nevertheless, it also has a very high birth rate(7.0).MexicoandIndonesia, on the other hand, are poor countries, with largely agricultural economies, but they have recently reduced their population growth.

    Clearly, other factors are involved. The most important of these is the condition of women.  A high birth rate almost always goes together with lack of education and low status for women. 2  This would explain the high birth rate ofSaudi Arabia. There, the traditional culture gives women little education or independence and few possibilities outside the home. On the other hand, the improved condition of women inMexico,Thailand, andIndonesiaexplains the decline in birth rates in these countries. Their governments have taken measures to provide more education and opportunities for women.

    Another key factor in the birth rate is birth control. Women may want to limit their families but have no way to do so. In countries where governments have made birth control easily available and inexpensive, birth rates have gone down. This is the case inSingapore,Sri Lanka, andIndia, as well as inIndonesia,Thailand,Mexico, andBrazil. In these countries, women have also been provided with health care and help in planning their families.

    These trends show that an effective program to reduce population growth does not have to depend on better economic conditions. 3 It can be effective if it aims to help women and meet their needs. Only then, in fact, does it have any real chance of success.

 

词汇: 

Industrialization  [ɪnˌdʌstrɪəlaɪ"zeɪʃn] n. 工业

Possibility  [ˌpɒsə"bɪlətɪ] n. 可能性,可能发生的事物

Effective  /i"fektiv/ adj. 有效的,起作用的,实际的

 

注释:

1. In atraditional agricultural economy, large families are helpful. Having more children meanshaving more workers in the fields and someone to take care of the parents in old age.传统的农业经济中,家庭成员数目多是十分有利的。孩子多意味着田里的劳动力多且有人给父母养老。

2.A high birth rate almost always goes together with lack of education and low status for women.高的生育率往往与妇女缺乏教育与社会地位低下相关。

3. These trends show" that "an effective program to reduce population growth does not have todepend on better economic conditions.这些趋势表明有效的控制人口的方案并不依赖于良好的经济状况。

In a traditional agricultural economy,a large family____.

A:can be an advantage B:may limit income C:isn"t necessary D:is expensive

Modern linguistics is different from traditional grammar.

Please name four traditional Chinese souvernirs.

The essential weakness of the old and traditional education was not just that it emphasized the necessity for provision of definite subject-matter and activities. These things are necessities for anything that can rightly be called education. The weakness and evil was that the imagination of educators did not go beyond provision of a fixed and rigid environment of subject-matter, one drawn moreover from sources altogether too remote from the experiences of the pupil. What is needed in the new education is more attention, not less, to subject-matter and to progress in technique. But when I say more, I do not mean more in quantity of the same old kind. I mean an imaginative vision which sees that no prescribed and ready-made scheme can possibly determine the exact subject-matter that will best promote the educative growth of every individual young person; that every new individual sets a new problem ;that he calls for at least a somewhat different emphasis in subject-matter presented. There is nothing more blindly stupid than the convention which supposes that the matter actually contained in textbooks of arithmetic, history, geography, etc. , is just what will further the educational development of all children.   But withdrawal from the hard and fast and narrow contents of the old curriculum is only the negative side of the matter. If we do not go far in the positive direction of providing a body of subject-matter much richer, more varied and flexible, and also in truth more definite, judged in terms of the experience of those being educated, than traditional education supplied, we shall tend to leave an educational vacuum in which anything may happen. Complete isolation is impossible in nature. The young live in some environment whether we intend it or not , and this environment is constantly interacting with what children and youth bring to it. and the result is the shaping of their interests, minds and character―either educatively or mis-educatively. If the professed educator gives up his responsibility for judging and selecting the kind of environment that his best understanding leads him to think will be contributive to growth, then the young are left at the mercy of all the unorganized and casual forces of the modern social environment that inevitably play upon them as long as they live. In the educative environment the knowledge , judgment and experience of the teacher is a greater, not a smaller factor, than it is in the traditional school. The difference is that the teacher operates not as a judge set on high and marked by arbitrary authority but as a friendly co-partner and guide in a common enterprise. There will be the risk of forming an educational blank if

A:the rigid school curricula are thoroughly transformed. B:the negative effect of old education is only partly recognized. C:the traditional subject-matter totally substitutes for new one. D:the replacement of unvarying courses with flexible ones fails.

Euthanasia is clearly a deliberate and intentional aspect of a killing. Taking a human life, even with subtle rites and consent of the party involved is barbaric. No one can justly kill another human being. Just as it is wrong for a serial killer to murder, it is wrong for a physician to do so as well, no matter what the motive for doing so may be.
Many thinkers, including almost all orthodox Catholics, believe that euthanasia is immoral. They oppose killing patients in any circumstances whatever. However, they think it is all right, in some special circumstances, to allow patients to die by withholding treatment. The American Medical Association’s policy statement on mercy killing supports this traditional view. In my paper "Active and Passive Euthanasia" I argue, against the traditional view, that there is in fact no normal difference between killing and letting die--if one is permissible, then so is the other.
Professor Sullivan does not dispute my argument; instead he dismisses it as irrelevant. The traditional doctrine, he says, does not appeal to or depend on the distinction between killing and letting die. Therefore, arguments against that distinction "leave the traditional position untouched."
Is my argument really irrelevant I don’t see how it can be. As Sullivan himself points out, nearly everyone holds that it is sometimes meaningless to prolong the process of dying and that in those cases it is morally permissible to let a patient die even though a few more hours or days could be saved by procedures that would also increase the agonies of the dying. But if it is impossible to defend a general distinction between letting people die and acting to terminate their lives directly, then it would seem that active euthanasia also may be morally permissible.
But traditionalists like professor Sullivan hold that active euthanasia--the direct killing of patients--is not morally permissible; so, if my argument is sound, their view must be mistaken. I can not agree, then, that my argument "leave the traditional position untouched. "
However, I shall not press this point. Instead I shall present some further arguments against the traditional position, concentrating on those elements of the position which professor Sullivan himself thinks most important. According to him, what is important is, first, that we should never intentionally terminate the life of a patient, either by action or omission, and second, that we may cease or omit treatment of a patient, knowing that this will result in death, only if the means of treatment involved are extraordinary.
The author’s purpose in writing this passage is

A:to air his opinions on Sullivan’s arguments. B:to attack the traditional view on euthanasia. C:to explain how his argument is much relevant. D:to draw a line between killing and letting die.

It is believed by scientists that traditional medicines

A:can cure all kinds of diseases. B:may cure some of today's most serious diseases. C:are no longer useful for modern men. D:are too cheap to be useful.

A Nowadays,Korea is influenced by American culture If you visit Seoul(汉城),you will see alot of fast food stores in sach avenue,p;aces such as KFC,MeDonald’s,and Burger King. You will also be surprised to see many western style clothes which are different form our traditional clothes such as the Han Bouk,When you go around department stores,youcan see many young students waiting in line to buy famous brands such as 96 New York jeans,Guess, Polo,Guest,Channel,and Cartiers.It hard to find clothes which represent(代表)traditional Korean culture.There are only a few stores which sell traditional clothing,and these stores are starting to disappear. When you visit middle schools in Korea,you will also find studenfs listening to music on their CD players ,mostly rock and roll,including the pop music of singers such as Britney Spires,Christina Aguilera,and Ricky Martin.Moreover,if you ask students to talk about Korean music traditions,they probably will not give you an answer at once. Now,however,there are some voices which ate urging to preserve pur own culture,One is an association which insisis people eat traditional food sucb as kimchi.They make wcb sites to show how tradintional Korean foods are bencficial for health and they advertise on TVregularly about traditional customs. they say that Koreans are losing their identity(特性),and they are also concerned bccause young people don’t even know about the traditional KOREAN HOLIDAYS yhey suggest that the government prepare extra programs to teach young students about korean traditions.Some middle schools have tried to do thismbut it isn’t working bery effeetively.What is the main parpose of the association( )

A:To encourage people to cat traditional food B:To make people realize their duties C:To make sure young people live healthlly D:TO keep their own way of life and culture alive

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