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新GRE写作名人素材库:巴斯德.

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  考生在新GRE写作中要格外重视思维逻辑与论据论证,平时注意积累素材,多收集一些新GRE写作论据论证例子。下面是小编为大家搜集的关于巴斯德的名人素材,希望能够帮助大家更好地备考新GRE写作,获得新GRE写作高分。

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  Pasteur, Louis 1822 -- 1895

  Chemist and biologist, famous for his germ theory and for the development of vaccines. Born December 27, 1822 in the small town of Dole, the son of a tanner. He studied in the college of Arbois and at Besancon, where he graduated in arts in 1840. As a student preparing for the prestigious Ecole Normale Superieure of Paris, he did not doubt his ability. When he gained admittance by passing fourteenth on the list, he rused entry; taking the examination again, he won third place and accepted. For his doctorate his attention was directed to the then obscure science of crystallography. This was to have a decisive influence on his career.

  Under special dispensation from the minister of education, Pasteur received a leave of absence from his duties as professor of physics at the lyc of Tournon to pursue research on the optical properties of crystals of the salts of tartrates and paratartrates, which had the capacity to rotate the plane of polarized light. He prepared 19 different salts, examined these under a microscope, and determined that they possessed hemihedral facets. However, the crystal faces were oriented differently; they were lt-handed or right-handed, thus having the asymmetrical relationship of mirror images. Furthermore, each geometric crystal variety rotated the light in accordance with its structure, while equal mixtures of the lt- and right-handed crystals had no optical activity inasmuch as the physical fects canceled each other. Thus he demonstrated the phenomenon of optical isomers.

  Pasteur was elated. He repeated his experiment under the exacting eyes of Jacques Biot, the French Academy&aposs authority on polarized light who had brought Eilhardt Mitscherlich&aposs work to Pasteur&aposs attention. The confirmation was complete to the last exacting detail, and Pasteur, then 26, became famous. The French government made him a member of the Legion of Honor, and Britain&aposs Royal Society presented him with the Copley Medal.

  In 1852 Pasteur accepted the chair of chemistry at the University of Strasbourg. Here he found an opportunity to pursue another dimension of crystallography. It had long been known that molds grew readily in solutions of calcium paratartrate. It occurred to him to inquire whether organisms would show a prerence for one isomer or another. He soon discovered that his microorganism could completely remove only one of the crystal forms from the solution, the levorotary, or lt-handed, molecule.

  In 1854, though only 31 years old, Pasteur became professor of chemistry and dean of sciences at the new University of Lille. The course of his activities is displayed in the publications which he gave to the world in the next decades: Studies on Wine (1866), Studies on Vinegar (1868), Studies on the Diseases of Silkworms (1870), and Studies on Beer (1876).

  Soon after his arrival at Lille, Pasteur was asked to devote some time to the problems of the local industries. A producer of vinegar from beet juice requested Pasteur&aposs help in determining why the product sometimes spoiled. Pasteur collected samples of the fermenting juices and examined them microscopically. He noticed that the juices contained yeast. He also noted that the contaminant, amyl alcohol, was an optically active compound, and hence to Pasteur evidence that it was produced by a living organism ("living contagion").

  Pasteur was quick to generalize his findings and thus to advance a biological interpretation of the processes of fermentation. In a series of dramatic but exquisitely planned experiments, he demonstrated that physical screening or thermal methods destroyed all microorganisms and that when no contamination by living contagion took place, the processes of fermentation or putraction did not take place either. "Pasteurization" was thus a technique that could not only preserve wine, beer, and milk but could also prevent or drastically reduce infection in the surgeon&aposs operating room. Another by-product of Pasteur&aposs work on fermentation was his elucidation of the fact that certain families of microbes require oxygen whereas others do not. This insight divided the scientific community, and it was only in 1897, two years after his death, that the dispute was resolved.

  In 1865 Pasteur was called upon to assist another ailing industry of France ilk manufacture hich was being ruined by an epidemic among silkworms. He took his microscope to the south of France and in an improvised laboratory set to work. Four months later he had isolated the pathogens causing the disease, and after three years of intensive work he suggested the methods of bringing it under control. Pasteur&aposs scientific triumphs coincided with personal and national tragedy. In 1865 his father died; and his two daughters were lost to typhoid fever in 1866. Overworked and gri stricken, Pasteur suffered a cerebral hemorrhage in 1868 which lt part of his lt arm and leg permanently paralyzed. Nonetheless, he pressed on, hardly with interruptions, on his study of silkworm diseases, already sensing that these investigations were but his apprenticeship for the control of the diseases of higher animals, including humans.

  The Franco-Prussian War, with its trains of wounded, stimulated Pasteur to press his microbial theory of disease and infection on the military medical corps, winning grudging agreement to the sterilization of instruments and the steaming of bandages. The results were spectacular, and in 1873 Pasteur was made a member of the French Academy of Medicine--a remarkable accomplishment for a man without a formal medical degree.

  Pasteur was now prepared to move from the most primitive manifestations of life, crystals and the simpler forms of life in the microbial world, to the diseases of the higher animals. The opportunity arose through a particularly devastating outbreak of anthrax, a killer plague of cattle and sheep in 1876/1877. The anthrax bacillus had already been identified by Robert Koch, and Pasteur now set about proving that the agent of disease was precisely the living organism and not a related toxin. He diluted a solution originally containing a source of infection of anthrax by a factor of 1 part in 100100. Even at this enormous dilution, the residual fluid carried death, thus proving that it was the constantly multiplying organism that was the source of the disease.

  In 1881 Pasteur had convincing evidence that gentle heating of anthrax bacilli could so attenuate the virulence of the organism that it could be used to inoculate animals and thus immunize them. In a dramatic demonstration of this procedure, carried out with the whole of France as witness, Pasteur inoculated one group of sheep with the vaccine and lt another untreated. Upon injection of both groups with the bacillus, the untreated died; the others lived, and thus a scourge that had crippling economic fects was brought under control.

  Pasteur&aposs ultimate triumph came with the conquest of rabies, the disease of animals, particularly dogs, which gives rise to the dreaded hydrophobia of humans. The problem here was that the causative agent was a virus, hence an entity not capable of growth in the scientists&apos broth which nurtured bacteria. Pasteur worked for five years in an fort to isolate and culture the pathogen. Finally, in 1884, in collaboration with other investigators, he perfected a method of cultivating the virus in the tissues of rabbits. The virus could then be attenuated by exposing the incubation material to sterile air over a drying agent at room temperature. A vaccine could then be prepared for injection. The success of this method was greeted with jubilation all over the world. Animals could now be saved, but the question arose as to the fect of the treatment on human beings. In 1885, a nine-year-old boy, Joseph Meister, was brought to Pasteur. He was suffering from 14 bites from a rabid dog. With the agreement of the child&aposs physician, Pasteur began his treatment with the vaccine. The injections continued over a 12-day period, and the child recovered.

  In 1888, a gratul France founded the Pasteur Institute, which was destined to become one of the most productive centers of biological study in the world. In the closing paragraphs of his inaugural oration, Pasteur said: "Two opposing laws seem to me now to be in contest. The one, a law of blood and death opening out each day new modes of destruction, forces nations always to be ready for the battle. The other, a law of peace, work and health, whose only aim is to deliver man from the calamities which beset him. The one seeks violent conquests, the other, the reli of mankind. The one places a single life above all victories, the other sacrifices hundreds of thousands of lives to the ambition of a single individual. The law of which we are the instruments strives even through the carnage to cure the wounds due to the law of war. Treatment by our antiseptic methods may preserve the lives of thousands of soldiers. Which of these two laws will prevail, God only knows. But of this we may be sure, science, in obeying the law of humanity, will always labor to enlarge the frontiers of life."

  Pasteur&aposs seventieth birthday was the occasion of a national holiday. At the celebration held at the Sorbonne, Pasteur was too weak to speak to the delegates who had gathered from all over the world. His address, read by his son, concluded: "Gentlemen, you bring me the greatest happiness that can be experienced by a man whose invincible beli is that science and peace will triumph over ignorance and war.... Have faith that in the long run ... the future will belong not to the conquerors but to the saviors of mankind."

  On September 28, 1895, honored by the world but unspoiled and overflowing with affection, Pasteur died near Saint-Cloud in Paris. His last words were: "One must work; one must work. I have done what I could." He was buried in a crypt in the Pasteur Institute. There is a strange postscript to this story. In 1940 the conquering Germans came again to Paris. A German officer demanded to see the tomb of Pasteur, but the old French guard rused to open the gate. When the German insisted, the Frenchman killed himself. His name was Joseph Meister, the boy Pasteur had saved from hydrophobia so long ago.

  希望小编整理的以上新GRE写作论据论证关于巴斯德的文章对各位考生有所帮助,大家可以选择几段来进行背诵,在GRE作文里作为论据进行论证。此外,也可以在平时多搜集一些比较好的论据,来增加作文的含金量。

新GRE写作名人素材库:巴斯德GRE写作素材:巴斯德

  考生在新GRE写作中要格外重视思维逻辑与论据论证,平时注意积累素材,多收集一些新GRE写作论据论证例子。下面是小编为大家搜集的关于巴斯德的名人素材,希望能够帮助大家更好地备考新GRE写作,获得新GRE写作高分。

  获得更多留学知识 请咨询澳际免费在线顾问

  Pasteur, Louis 1822 -- 1895

  Chemist and biologist, famous for his germ theory and for the development of vaccines. Born December 27, 1822 in the small town of Dole, the son of a tanner. He studied in the college of Arbois and at Besancon, where he graduated in arts in 1840. As a student preparing for the prestigious Ecole Normale Superieure of Paris, he did not doubt his ability. When he gained admittance by passing fourteenth on the list, he rused entry; taking the examination again, he won third place and accepted. For his doctorate his attention was directed to the then obscure science of crystallography. This was to have a decisive influence on his career.

  Under special dispensation from the minister of education, Pasteur received a leave of absence from his duties as professor of physics at the lyc of Tournon to pursue research on the optical properties of crystals of the salts of tartrates and paratartrates, which had the capacity to rotate the plane of polarized light. He prepared 19 different salts, examined these under a microscope, and determined that they possessed hemihedral facets. However, the crystal faces were oriented differently; they were lt-handed or right-handed, thus having the asymmetrical relationship of mirror images. Furthermore, each geometric crystal variety rotated the light in accordance with its structure, while equal mixtures of the lt- and right-handed crystals had no optical activity inasmuch as the physical fects canceled each other. Thus he demonstrated the phenomenon of optical isomers.

  Pasteur was elated. He repeated his experiment under the exacting eyes of Jacques Biot, the French Academy&aposs authority on polarized light who had brought Eilhardt Mitscherlich&aposs work to Pasteur&aposs attention. The confirmation was complete to the last exacting detail, and Pasteur, then 26, became famous. The French government made him a member of the Legion of Honor, and Britain&aposs Royal Society presented him with the Copley Medal.

  In 1852 Pasteur accepted the chair of chemistry at the University of Strasbourg. Here he found an opportunity to pursue another dimension of crystallography. It had long been known that molds grew readily in solutions of calcium paratartrate. It occurred to him to inquire whether organisms would show a prerence for one isomer or another. He soon discovered that his microorganism could completely remove only one of the crystal forms from the solution, the levorotary, or lt-handed, molecule.

  In 1854, though only 31 years old, Pasteur became professor of chemistry and dean of sciences at the new University of Lille. The course of his activities is displayed in the publications which he gave to the world in the next decades: Studies on Wine (1866), Studies on Vinegar (1868), Studies on the Diseases of Silkworms (1870), and Studies on Beer (1876).

  Soon after his arrival at Lille, Pasteur was asked to devote some time to the problems of the local industries. A producer of vinegar from beet juice requested Pasteur&aposs help in determining why the product sometimes spoiled. Pasteur collected samples of the fermenting juices and examined them microscopically. He noticed that the juices contained yeast. He also noted that the contaminant, amyl alcohol, was an optically active compound, and hence to Pasteur evidence that it was produced by a living organism ("living contagion").

  Pasteur was quick to generalize his findings and thus to advance a biological interpretation of the processes of fermentation. In a series of dramatic but exquisitely planned experiments, he demonstrated that physical screening or thermal methods destroyed all microorganisms and that when no contamination by living contagion took place, the processes of fermentation or putraction did not take place either. "Pasteurization" was thus a technique that could not only preserve wine, beer, and milk but could also prevent or drastically reduce infection in the surgeon&aposs operating room. Another by-product of Pasteur&aposs work on fermentation was his elucidation of the fact that certain families of microbes require oxygen whereas others do not. This insight divided the scientific community, and it was only in 1897, two years after his death, that the dispute was resolved.

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