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  3. Dorothy Crowfoot Hodgkin When Dorothy Crowfoot Hodgkin was ten years old, she watched her first crystals form on a string da

Dorothy Crowfoot Hodgkin When Dorothy Crowfoot Hodgkin was ten years old, she watched her first crystals form on a string da

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问题               Dorothy Crowfoot Hodgkin
    When Dorothy Crowfoot Hodgkin was ten years old, she watched her first crystals form on a string dangling in a glass of salt water. Many children before and since have done the same, but in Hodgkin’s case, the sparkling geometric shapes kindled a fascination that would lead her to world fame.   In 1964, nearly half a century later, Hodgkin received a Nobel Prize in Chemistry for discovering the structures of penicillin and vitamin B12 from photographic images of their crystals. She made the images with a technique called x-ray crystallography, which involves firing x-rays through a crystal to determine the arrangement of the atoms in it. It is a bit like determining the shape of a jungle gym from its shadow.
    Born in 1910, Hodgkin spent the first few years of her life in Cairo, where her father was an official in the British colonial government. Most of her education had been at home, but once back at school in England, her keen interest in crystals won the attention of her schoolteacher. Hodgkin and a friend got special permission to join the boys studying chemistry. By age 12, she was doing chemistry experiments on rocks she found in her garden to see what they contained.   That summer, while visiting her father in Khartoum, Sudan, she met Dr. A. E. Joseph, a friend of her father’s and a well-known soil chemist. Joseph took her on a tour of his laboratory. Pleased by her intense interest, he put together a small chemistry set for her, which she took back to England and set up in her mother’s attic. It was her first laboratory.
    Hodgkin enrolled at Oxford University,  where she eventually specialized  in x-ray crystallography. At the time, the analysis of the structures of even the simplest chemicals by x-ray crystallography required at least 30 sets of calculations, all done by hand. The work demanded perseverance and diligence, and a good head for math. Under these conditions, Hodgkin flourished.   Seeking a greater challenge after college, Hodgkin went to Cambridge to study with a young crystallographer named J.D. Bernal. Together they solved some of the most complex chemical structures ever attempted, including those of several vitamins and sex hormones. They took the first x-ray photographs of a protein—the stomach enzyme pepsin—showing that proteins form regular crystals.   In 1937, Hodgkin received her doctorate. Within a few months, she also married historian Thomas Hodgkin, taking his name. The Hodgkins were a two-career family, working in different towns and commuting on alternate weekends to see each other. Dorothy Hodgkin remained at Oxford, where she continued her research, taught university classes, and raised three children.   When the demand for penicillin soared during World War Ⅱ, chemists all over the world raced to determine its structure. Experimental chemists used chemical reactions. Structural chemists, such as Hodgkin, used crystallography. Despite daunting calculations, Hodgkin and her students at Oxford completed the structure in 1949, beating the experimental chemists and establishing x-ray crystallography as an indispensable tool in biochemistry. Even as Hodgkin was finishing her analysis of penicillin, however, she had already begun a study of B12, widely used to treat pernicious anemia. In 1957, she published the structure of this 180-atom molecule.   (A) [■] When she was awarded the Nobel Prize in 1964, she told a group of students at the ceremonies in Stockholm, Sweden, that she hoped her position as the only woman to receive the prize that year "will not be so very uncommon in the future, as more and more women carry out research in the same way as men".   
(B) [■] But what was perhaps Hodgkin’s greatest success came after the Nobel Prize, when she tackled the biggest molecule of her career. Insulin, a protein that regulates the body’s sugar storage, contains over 1000 atoms.
(C) [■] A deficiency in or insensitivity to insulin causes diabetes, a complex disease that causes suffering in several hundred million people worldwide. Hodgkin solved the structure of insulin in only five years.  
(D) [■] Her achievement proved that proteins have regular shapes, and it spawned research that ultimately led to effective treatments for diabetes.
In Paragraph 7, what can be inferred about the relationship between chemists and demand of the time?
选项 A、They tried to solve the urgent problems of the time.
B、They are mostly employed by the government.
C、They know how to remain useful in changing times.
D、They are afraid of losing touch with the world.
答案A
解析 本题仍为推论题。题目问：在第七段中，关于化学家和时代的要求之关系可以做出什么推论?根据本段第一句话“When the demand for penicillin soared during World War Ⅱ, chemists all over the world raced to determine its structure(当青霉素的需求在第二次世界大战时急速上升时，世界各地的化学家都在争分夺秒地抢先确定它的结构)”可以得知，化学家总是设法解决当时最紧迫的问题，所以选A。
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