题目内容

Ronald Hoffman born in 1937 is Polish-born American organic chemist and Nobel laureate(桂冠). As a theoretical chemist, Hoffmann studied energy levels in chemical bonds during chemical reactions. He put computers to use to solve his problems and, despite the complexity of his research, was able to explain his theories and discoveries to the non-specialist. For his work he was awarded the 1981 Nobel Prize in chemistry, which he shared with Fukui Kenichi.

Born in Poland, Hoffmann settled in New York City as a child and became a United States citizen. He received his undergraduate degree in premedical studies from Columbia College in 1958. He attended Harvard University, where he received his PhD. degree in chemical physics in 1962. He joined the faculty of Cornell University in the mid-1960s and remained there throughout his career.

Hoffmann and Nobel laureate chemist Robert Burns Woodward developed rules, based on quantum mechanics, to determine how energy levels in atomic electron orbits influence how a chemical reaction takes place. These simple rules, known as the Woodward-Hoffmann rules, allowed chemists to predict reaction results and was quickly accepted and put to use in a wide variety of situations.

Hoffmann later turned his research to a variety of problems related to discovering the molecular structure of inorganic and organometallic compounds. Hoffmann is also known for what is called the Isolobal Analogy, which is yet another discovery linking all areas of chemistry. It is useful in predicting the behavior of new molecules based on the orbit structure of the components used to form them.

Aided by computers, Hoffmann was able to generate a vast amount of data to support his ideas. Unlike the scientific papers of many chemists, Hoffmann's publications contain little raw data but instead are filled with diagrams and pictures to explain his results. His drawings of shaded balloons to indicate eigenvectors, a unit used in mathematics, are now the accepted scientific notation for illustrating this value.

1.What can be inferred from the above passage about Hoffman?

A. He left his homeland when he got the Nobel Prize.

B. He went to the United States to gain his Nobel Prize.

C. He might find the Unites States a better place to learn chemistry.

D. His family may have settled in the United States.

2.How did Hoffman make his research popular?

A. He applied some computer skills to help explain his ideas.

B. He established a special computer system to help.

C. He drew some forms explaining his ideas.

D. He did series of experiments to prove his ideas.

3.The underlined word “generate” in this passage might most probably mean “______”.

A. bring in B. break down

B. move away D. keep secret

4.Why was Ronald Hoffman awarded the 1981 Nobel Prize for chemistry?

A. He established rules to predict chemical reactions .

B. He succeeded applying computer science to chemistry research.

C. He shared what he had achieved with another scientist named Fukui Kenichi.

D. He succeeded in both chemistry and computer researches.

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Modern festival-goers who worry about ending up with a dead mobile phone battery(电池) after days stuck in a muddy field with no electric plug power points may now have a solution——power boots(靴子).

Mobile phone company European Telco Orange has introduced a phone charging(充电) prototype—— a set of thermoelectric gumboots or Wellington boots with a “power generation sole” that changes heat from the wearer’s feet into electrical power to charge battery-powered hand-helds.

The boot was designed by Dave Pain, managing director at GotWind, a renewable energy company. Pain said the boot uses the Seebeck effect, in which a circuit made of two dissimilar metals conducts electricity if the two places where they connect are held at different temperatures. “In the sole of the Wellington boot there’s a thermocouple and if you apply heat to one side of the thermocouple and cold to the other side it produces an electrical charge,” Pain said. “That electrical charge we then pass through to a battery which you’ll find in the heel of the boot for storage of the electrical power for later use to charge your mobile phone.” These thermocouples are connected electrically, forming an array of multiple thermocouples (thermopile). They are then sandwiched between two thin ceramic wafers. When the heat from the foot is applied on the top side of the ceramic wafer and cold is applied on the opposite side, from the cold of the ground, electricity is made.

But the prototype boot does have one drawback. You have to walk for 12 hours in the boots to make one hour’s worth of charge.

1.The passage is probably taken from _____________ of a website.

A. the business book B. the sports book

C. the science book D. the health book

2.What’s the main idea of the third paragraph?

A. How the boot works to make electricity.

B. How long the boot can be used.

C. Who invented the power boot.

D. The weakness of the boot.

3.Which of the following can replace the underlined word “drawback” in the last paragraph?

A. Benefit. B. Disadvantage.

C. Patience. D. Function.

4.The invention seems to be good news to those___________.

A. who like traveling in the wild

B. who work at home

C. who study at school

D. who work at an office

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项,选项中有两项为多余选项。

If tests can make students nervous, anxious and even scared, shouldn’t schools just get rid of them? 1. Teachers and schools give students tests for very important reasons:

2. Giving a test is a way for a teacher to see which students are learning the skills and knowledge they should be learning, and which ones are having trouble. Depending on how kids do on the test, the teacher will know if he or she must go back over some things, or if it’s okay to keep moving forward。

To see how well your school is teaching you. All parents want their kids to finally graduate with the ability to earn a living. 3. And one way to do this is to have them take test.

To assign (指定) grades. 4. Besides your homework, tests are one of the best ways for you to show the teacher that you’ve really learned what’s being taught, and for the teacher to figure out what grade you should get. Grades are also a way to show your parents how you’re doing in school.

To keep you motivated(有积极性的). Admit it: you work harder if you know someone is checking up on your work. For example, if your mom tells you to clean your room but you know she will never go in and check, then you might not do it, right? 5. Because you know that you’ll eventually have to take a test on the material and you might be more likely to give it that extra effort and make sure you know everything you’re supposed to know.

A. To see if you’re learning.

B. To see if you are totally prepared.

C. Students must work hard to get good grades.

D. Well, believe it or not, tests don’t just exist to trouble you.

E. Grades are important in most schools, and tests play a big role.

F. So schools have to prove they’re trying their best to educate students.

G. Well, tests help make sure that you don’t leave your homework behind.

Answering the Community Needs of Our City

The Silver City Council recognizes that citizens have certain needs.To better meet your needs,we have made several changes to community facilities in 2014.The followings show how we have tried to make your life better.

Transport

☆Three stations for the suburbs have been added to the western train service.

☆20 new buses for the southern line were purchased in January.

☆50 per cent of city bus stops have been upgradeD.

Communication

☆Broadband cable is now av ailable to all parts of the city.

☆All of the new Government buildings are smart wired for better computer service!

Medical Facilities

☆The new state of the art Nightingale Hospital was opened in June.

☆To overcome a shortage of trained medical staff at Dover Hospital,10 doctors have been employed from overseas.

☆Some facilities at Station Street Hospital have been upgradeD.

Education

☆Textbooks will be free to all primary students in 2014!

☆Rental for private schools has been reduceD.

Protection and Security

☆Extra police now patrol(巡逻)the tourist areas.

☆50 new police officers graduated in July and have taken up duties in the city areA.

Entertainment / Recreation

☆The new Central Community Building opened in May.

☆5,000 new fiction books were bought for the Silver City Library.

1.What is the purpose of the changes in Silver City?

A. To satisfy all the needs of the citizens.

B. To make public service improveD.

C. To better the citizens’life.

D. To meet the needs of the Silver City Council.

2.What can we learn from the passage?

A. Travel books are provided in the new library.

B. More bus lines and stops are bought in Silver City.

C. Free medical treatment is available at Station Street Hospital.

D. There are more police officers on duty now.

3.The public notice is from _______.

A. the community

B. the local government

C. the Silver City Library

D. a travel agency

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