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PRELOG, Vladimir
Yugoslavian-Swiss chemist
Austria-Hungary), July 23, 1906 Prelog was educated in Prague and at one time studied under Ruzicka [1119]. In 1935 he joined the faculty of the Uni versity of Zagreb in Yugoslavia; but in 1941, when the German army invaded 815
[1311] SABIN
FOLKERS [1312]
the country, he fled to Switzerland, where he remained afterward. Using X-ray diffraction techniques he determined the structure of several anti biotics. He also worked out systematic rules for determining whether a particu lar asymmetric compound is “dextra” or “levo,” that is, has a certain structure or the mirror image of that structure. For this he was awarded a share of the 1975 Nobel Prize for chemistry. [1311] SABIN, Albert Bruce Polish-American microbiologist
land), August 26, 1906 Like Salk [1393] of Polish-Jewish de scent, Sabin arrived in the United States in 1921 and was naturalized in 1930. He attended New York University, going to dental school at first, but becoming inter ested in microbiology and shifting to medicine. He obtained his medical de gree in 1931 and in 1939 became profes sor of pediatrics at the University of Cincinnati Medical School. During World War II he served as a medical officer in the army, fighting against such diseases as encephalitis. After the war, however, he turned to po liomyelitis which had concerned him in his younger days, when, a decade before Enders [1195], he attempted to grow polio virus outside intact organisms. Sabin was not convinced that the Salk technique of using dead virus was ade quate. He believed that only living virus could be counted on to produce the nec essary antibodies over a long period. Furthermore, living virus could be taken by mouth, since they would multiply and invade the body of their own accord, and would not, like the Salk vaccine, have to be injected by needle. The trick was to find virus strains of each of the three types of polio (each producing its own variety of antibody) that were too feeble to produce the disease itself. When Sabin thought he had the proper strains, judging by animal experiments, he tried them on himself first, then on prison volunteers. By 1957 he had live vaccines of each polio type that he con sidered satisfactory. The Sabin vaccine proved popular in the Soviet Union and it was widely used there and in other East European nations. It was not till 1960, however, that the vaccine came into use in the United States. [1312] FOLKERS, Karl August American chemist
ber 1, 1906 Folkers graduated from the University of Illinois in 1928 and went on to obtain his Ph.D. in 1931 at the University of Wisconsin. After postdoctorate work at Yale University, Folkers became an in dustrial chemist, finding his niche at Merck & Company in 1934. There he rose in rank until he was director of fun damental research by 1956. Merck is a pharmaceutical house, and a particularly important field of interest for such a firm during the vitamin-cen tered 1930s was the possibility of prepar ing synthetic vitamins. Through the 1930s Folkers and the rest of the Merck group helped establish the chemical structure (by synthesis) of various members of the B-vitamin group, includ ing pyridoxine, biotin, and pantothenic acid.
Their most startling work, however, came in connection with the antiper nicious anemia factor that had been lo cated in liver by Minot [1103] and Murphy [1154], while Folkers was still a college student. Feeding liver in large quantities to patients with pernicious anemia was life-saving, to be sure, but could become a form of torture, since liver doesn’t wear well as a constant arti cle of diet. Obviously if the vitamin could be administered without the sur rounding liver, matters would be greatly improved. Through the 1930s attempts were made to isolate the factor, which was suspected of being one of the B vitamins and was, in fact, given the name vitamin B12. Liver extracts rich in vitamin B12 were obtained, but progress was slowed by the difficulty of assaying the extracts for vitamin potency. For twenty years after 816
[1312] FOLKERS
DELBRÜCK [1313]
the Minot-Murphy discovery, the only way of making such an assay was to feed the various extracts and fractions to pa tients with pernicious anemia and then to observe the rate at which a certain type of immature red blood cell, the re ticulocyte, was formed in response. In 1948 it was discovered at Merck that certain bacteria required vitamin B12 for growth. If those bacteria were supplied a nutrient medium containing all required factors but vitamin B12, their rate of growth would then be in propor tion to any added quantity of vitamin B12. In this way, the vitamin content of any extract could quickly be determined without trouble to human patients. The process of purification was speeded enormously and soon red crys tals were obtained that proved to be the vitamin itself. Folkers and his group ac complished the isolation at Merck, just as another group, in England, was ac complishing it as well (and without the advantage of bacterial assay). Vitamin B12 turned out to be an amaz ing compound in a number of ways. It is required by the body in far smaller quantities than ordinary vitamins are, and it has such a complicated molecule that the final determination of its struc ture was made by measurements of elec tron densities, measurements that proved so complicated that a modem computer was required to complete the inter pretation. This was carried through in 1956 by D. C. Hodgkin [1352], Two surprising points were made in connection with the structure. First, a cyanide group was included in the mole cule and second, a cobalt atom. The compound was named cyanocobalamine, the first naturally occurring compound found to contain cobalt. This explained why cobalt is a trace element necessary to life.
A person with pernicious anemia does not suffer necessarily from any lack of cyanocobalamine in his diet, since the small amounts required are present in any normal diet. And if they weren’t, they would be formed by the intestinal bacteria as long as a trace of cobalt was present in the diet. The pernicious ane mic, however, lacks a particular sub stance in the gastric juice without which he cannot absorb the large molecule of the vitamin. In this area, research still continues. In a sense, the isolation of cyanoco balamine (which is now produced in quantity from bacterial cultures, is rou tinely included in vitamin pills, and has removed pernicious anemia from the list of medical problems) marks the climax of the vitamin research that began a half century earlier with Eijkman [888], What remains to be done is of bio chemical rather than medical importance; the various vitamins must be placed in their respective metabolic niches. This is being rapidly accomplished for the B vi tamins, beginning with the work of El vehjem [1240] in the 1930s, and even the vitamins outside that group are be ginning to fall into place, a notable ex ample being Wald’s [1318] work with vi tamin A.
Folkers was involved in matters other than vitamins. After World War II, anti biotics moved into the forefront of phar maceutical problems and in 1948 Folkers’ group was among those who worked out the chemical structure of Waksman’s [1128] streptomycin. In 1963 he became president of the Stanford Research Institute in Menlo Park, California. [1313] DELBRÜCK, Max German-American microbiologist Born: Berlin, September 4, 1906 Died: Pasadena, California, March 9, 1981 Delbrück obtained his Ph.D. from the University of Göttingen in 1930, did postdoctoral work in Copenhagen under Bohr [1101], and then worked in Berlin with Hahn [1063] and Meitner [1060]. He left Germany after Hitler came to power, reaching the United States in 1937 and becoming an American citizen in 1945. He joined the faculty of the California Institute of Technology. While he was still in Berlin his interest had begun shifting from nuclear physics to genetics, and in California he grew absorbed in bacteriophages, the compar 817
[1314] LELOIR
EDLÉN [1316]
atively large viruses that infest bacterial cells. He discovered an improved method of culturing bacteriophages and found that once a bacterial cell was infected by a single bacteriophage, that cell broke up in half an hour, leaving a hundred bac teriophages behind, each ready to infect another bacterial cell. Delbrück and Hershey [1341] indepen dently discovered in 1946 that the ge netic material of different viruses could be combined to form a virus different from either. This founded the study of bacterial genetics and led a generation later to the achievements of microbiol ogists such as Berg [1470] and their work with recombinant DNA. For their findings, Delbrück and Her shey shared, with Luria [1377], the 1969 Nobel Prize for physiology and medi cine. [1314] LELOIR, Luis Frederico Argentinian biochemist Born: Paris, France, September 6, 1906
Leloir was educated at the University of Buenos Aires and remained on the faculty there. He studied the synthesis and breakdown of complex sugars, dis covering sugar nucleotides that serve as intermediates, and liver enzymes that are essential to the process. As a result, he received the 1970 Nobel Prize for chem istry. [1315] LEY, Willy flay) German-American engineer Born: Berlin, Germany, October 2, 1906
Died: New York, New York, June 24, 1969 Ley studied at the University of Berlin and might have become a zoologist but in 1925 discovered a book on rocketry that caught his imagination. He wrote a popularized version of his own that met with wide acclaim and for over forty years afterward he remained the most successful popular writer on rocketry in the world. Nor was he content merely to write. He helped found the German Rocket So ciety in 1927, the first group of men— with the solitary exception of Goddard [1083]—to experiment with rockets. Wemher von Braun [1370] was intro duced into the organization by Ley, who was also consultant for the science fiction movie Frau im Mond in which the countdown from ten to zero was in troduced. When Hitler came to power, Ley was soon in trouble. Fiercely anti-Nazi, he was not content to pursue his rocket studies regardless of the political atmo sphere as did Von Braun. Ley came to the United States in 1935 and became a naturalized American citizen in 1944. In the United States, Ley was inti mately involved on the one hand with the strong science fiction literary movement and on the other with his serious interest in rocketry. He, more than anyone else, prepared the climate within the United States for the space effort. In the end, however, he died just three weeks before Armstrong [1492] touched down on the moon. Like Moses, he led the way but could not enter the Prom ised Land. [1316] EDLÉN, Bengt Swedish physicist
Edlén obtained his doctorate at Upp sala in 1934, and remained on its faculty with professorial rank till 1943, when he moved on to the University of Lund. He was particularly interested in the analyses of spectra in the extreme ultra violet range and used his findings to deal with particularly hot stars that would be expected to produce large quantities of radiation in that range. Rather unexpectedly, he found it pos sible to use his studies on the sun itself. To be sure, its surface is only 6,000°K in temperature but its surface is the coolest part of itself. Not only is it hotter in its depths, but while the total heat de clines as one moves upward from the surface, it is distributed among particles, the total number of which per unit vol 818
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GOLDMARK [1319]
ume decreases even more rapidly, so that the heat per particle, or temperature, rises. In 1940 Edlen maintained that the solar corona has a temperature in the million-degree range and this was even tually well confirmed. [1317] WHIPPLE, Fred Lawrence American astronomer Born: Red Oak, Iowa, November 5, 1906
Whipple studied at the University of California, graduating in 1927 and ob taining his Ph.D. in 1931. He joined the faculty of Harvard University in the lat ter year and remained there afterward. He was particularly interested in the mavericks of the solar system, its comets and meteoroids. Whipple suggested, in 1949, that the comets are composed largely of frozen hydrogen-containing compounds (ammonia, methane, and so on) cemented together, perhaps, by con glomerates of silicates, or ordinary rock. This is reminiscent of the general com position of the outer planets, as Wildt [1290] had made clear, and if the comets originate in a far-flung asteroid belt be yond the outer planets, as Oort’s [1229] theory holds, it is reasonable to suppose this to be their composition. At an ap proach to the sun, some of the hydro gen-containing “ices” are vaporized and, with silicate dust, are swept back by the solar wind to form the cometary tail. Whipple, as a science fiction enthusi ast, must have found it a dream come true to be intimately involved in the man-made satellite project of the late 1950s. He was director of the Smith sonian Astrophysical Observatory after 1955 and headed the optical tracking system in the United States, a system that mobilized hundreds of observers (professional and amateur) to trace the satellites that began streaking across the sky in late 1957. [1318] WALD, George American chemist Born: New York, New York, No vember 18, 1906 Wald graduated from New York Uni versity in 1927 and obtained his Ph.D. at Columbia University in 1932. After working under Karrer [1131] in Ziirich, and at the University of Chicago, he joined the faculty of Harvard University in 1934 and remained there afterward. His chief interest was in the chemistry of vision. The rods of the retina, which function in dim fight, contain a pigment (visual purple, or rhodopsin) that, Wald showed, consists of a protein (opsin) in combination with a compound called ret- inene. Retinene is very similar in struc ture to vitamin A and is formed from vitamin A in the body. When fight strikes rhodopsin, the protein and the ret inene separate; they recombine in the dark. For more than a quarter century Wald and his group worked out the details of these changes with precision. In the pro cess of light-dark changes, some retinene is irreversibly altered and drizzles away, so to speak. More is formed out of the more stable vitamin A. Where the diet is deficient in vitamin A over an extended period, the body’s stores of that com pound are used up and there is no way of forming additional retinene. The rods will no longer function normally and the eye will not respond to dim light. It is for this reason that one of the symptoms of vitamin A deficiency (though not the only one) is night blindness. For this work Wald shared the 1967 Nobel Prize in physiology and medicine. Still later, and rather unexpectedly as the result of an impromptu speech he made, he emerged into nationwide fame as a spokesman for the peace movement and youth rebellion that swept the United States during the Vietnam War. [1319] GOLDMARK, Peter Carl Hungarian-American physicist
1906
Died: Westchester County, New York, December 7, 1977 Goldmark studied at the University of Vienna and obtained his Ph.D. there in 1931. He came to the United States in 819
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RUSKA [1322]
1933 and became an American citizen in 1937.
He worked at the Columbia Broad casting System Laboratories from 1936 to 1971 and became president of the laboratories in 1954. He is notable for two advances that have intimately affected the lives of many millions the world over. In 1948 he developed the long-playing (LP) rec ord, which turned 33V6 times per min ute rather than the till then regulation 78. A single LP record could hold six times the amount of music of the old kind. Earlier, in 1940, he had developed the first color television system used in commercial broadcasts. He also contrib uted to the scanning system that made it possible for viewers on Earth to receive photographs taken of and relayed from the moon. [1320] WILKINS, Robert Wallace American physician
December 4, 1906 Wilkins received his medical degree from Harvard University Medical School in 1933 and served on the faculty of Boston University Medical School after 1940. He is best known for his introduction into the United States of a drug derived from the root of an Indian shrub. It had been used in India in the treatment of high blood pressure and beginning in 1950 Wilkins used it for this purpose at the Massachusetts Memorial Hospital. In 1952 he reported on its sedative and tranquilizing effect and the drug, which was named reserpine, was the first of the tranquilizers. The tranquilizers have the advantage over earlier sedatives, like barbiturates, in that they produce their calming effect without diminishing alertness or bringing on sleep. Tranquilizers are popular with many people for the reduction (real or fancied) of tensions (real or fancied), but they serve more important uses, too. They are an important adjunct in psychi atric treatment, for, although they are in no sense a cure for any mental disease, they do calm violent patients without the use of harsh physical restraints, and calmed patients are more easily reached by the psychiatrist. Their overuse as a crutch has led to problems of addiction that are by no means trivial. [1321] ZINN, Walter Henry Canadian-American physicist
cember 10, 1906 After graduation from Queen’s Uni versity, Zinn went to the United States in 1930 (he was naturalized in 1938) and obtained his Ph.D. at Columbia Univer sity in 1934. In 1939 he was one of those American physicists who quickly confirmed Meit ner’s [1060] theory of uranium fission, and during World War II he worked on the development of the nuclear bomb. It was he who withdrew the control rod in the first nuclear reactor in 1942 and made it self-sustaining. After the war he became director of the Argonne National Laboratories in Chicago. He specialized in the design of nuclear reactors and in 1951 built the first exper imental breeder reactor in Idaho. Where ordinary reactors obtain their energy through the fission of uranium-235, a breeder reactor, in the process of obtain ing this energy, converts uranium-238 to additional uranium-235. Generally, breeder reactors produce or breed more fuel than they consume. Such reactors make all the uranium and thorium re sources of the earth available for use as nuclear fuel. In 1959 Zinn became vice president of Combustion Engineering. [1322] RUSKA, Ernst August Friedrich German electrical engineer Born: Heidelberg, December 25, 1906
Ruska qualified as an engineer at the University of Berlin in 1931 and earned a doctor’s degree in 1934. By then he had already made his mark in the world of science. Since electrons 820
[1323] YUKAWA
YUKAWA [1323]
possess a wave aspect (as De Broglie [1157] had reasoned and Davisson [1078] had demonstrated) they ought to be capable of being treated in a fashion analogous to light waves. Since electrons were electrically charged, they could be manipulated by magnetic fields and fo cused much as light waves were focused by lenses. Why not, then, an “electron microscope”? Since the shorter the length of waves being used, the greater the magnification, and since electron waves were much shorter than the waves of ordinary light, it followed that electron microscopes ought to be much more powerful than ordinary optical microscopes. And so they were. Even the first crude instrument, built in 1932 by Ruska and a collaborator, Max Knoll, was capable of magnifying 400 times. The electron microscope did not actually become practical, however, until the later, improved model of Hillier [1401], [1323] YUKAWA, Hideki (yoo-kah'- wah) Japanese physicist Bom: Kyoto, January 23, 1907 Died: Kyoto, September 8, 1981 Yukawa was educated at Kyoto Uni versity, where his father was a professor of geology, graduating in 1929. He did his graduate work at Osaka University, earning his Ph.D. there in 1938, while serving on its faculty. In the middle 1930s Yukawa ad dressed himself to the problem of what holds the nucleus of an atom together. After Chadwick [1150] discovered the neutron in 1932, Heisenberg [1245] had pointed out that the atomic nucleus must be made up of protons and neutrons only. If this was so, then only positive electric charges were to be found in the nucleus and these should exert a strong repulsion among themselves, particularly when as close to each other as they must be in the nucleus. Heisenberg had sug gested the existence of “exchange forces” but had not pinpointed what those ex change forces might be. Yukawa reasoned that ordinary elec tromagnetic forces involved the transfer of photons and that within the nucleus there must be a “nuclear force” involv ing the transfer of some other entity. Such a nuclear force, if it existed, must be very short-range. That is, over dis tances not greater than the span of the nucleus (about a ten-trillionth of a centi meter), the force must be very strong, strong enough to overcome the repulsive forces between the positive charges of the various protons. However, the force must decrease very rapidly with distance, for outside the nucleus at the distance of even the nearest electrons it could no longer be detected. Yukawa evolved a theory whereby such a force evidenced itself by transfers of particles among the neutrons and protons of the nucleus. These particles possessed mass, and the shorter-range the force, the greater the mass would have to be. For a force evidencing itself only across the width of the nucleus, the mass of the particle being transferred would have to be about two hundred times that of the electron and about one- ninth that of a proton or neutron. In 1935, when Yukawa published his theories, no such intermediate-sized par ticle was known. The very next year, however, C. D. Anderson [1292] discov ered one, and it came to be called a meson. For a while it seemed as though Yukawa’s theory had been substantiated, and so it was, to the extent that a parti cle of intermediate size could exist. (The particle was very short-lived, to be sure, but Yukawa’s theory had predicted that.)
Unfortunately Anderson’s meson (the mu-meson or muon) did not interact with atomic nuclei to any great extent and Yukawa’s theory required such in teraction. However, in 1947 a second, slightly heavier meson (the pi-meson) was discovered by Powell [1274] and this second meson fulfilled all require ments. Yukawa was deemed worthy of the 1949 Nobel Prize in physics, the first Japanese to win a Nobel award. In 1936 Yukawa had also predicted that a nucleus could absorb one of the innermost of the circling electrons and 821
[1324] VEKSLER
VEKSLER [1324]
that this would be equivalent to emitting a positron. Since the innermost electrons belong to the “K shell,” this process is termed “K capture.” This prediction was verified in 1938. In 1948 Yukawa, at the invitation of Oppenheimer [1280], visited the Institute for Advanced Study at Princeton, then lectured at Columbia University until 1953, when he returned to Kyoto Uni versity. [1324] VEKSLER, Vladimir Iosifovich Soviet physicist
4, 1907
Died: Moscow, September 22, 1966
Veksler, the son of an engineer, gradu ated from the Moscow Energetics Insti tute in 1931. He was an important figure in high- energy experimental physics and in the development of particle accelerators. In 1945 he suggested a method for design ing a cyclotron that would allow for relativistic changes in the mass of accel erating particles and thus achieve greater energies. McMillan [1329] independently proposed the same method a few years later. Synchrocyclotrons were built along these lines in the late 1940s, and as a re sult in 1963 Veksler shared with McMil lan the Atoms for Peace award. [1325] BOVET, Daniele (boh-vayO Swiss-French-Italian pharmacolo gist
Born: Neuchâtel, Switzerland, March 23, 1907 Bovet, the son of a professor of peda gogy, was educated at the University of Geneva, obtaining his doctorate in 1929, and did his important work at the Pas teur Institute in Paris. This began with the announcement of the discovery of Prontosil by Domagk [1183] in 1935. Prontosil (a trade name) was effective against streptococci in the body, but, added to streptococci cultures in test tubes, it had no effect. To Bovet and his colleagues at the Pasteur Institute, it seemed clear that this was best explained by supposing that Pron tosil was changed into something else in the body and that it was the “something else” that handled the bacteria. The eas iest way of changing Prontosil was to break its molecule into several frag ments. One of these was a well-known compound, sulfanilamide. This was tested at the Pasteur Institute in 1936 and proved to be as effective in the test tube as in the body. In 1937 Bovet be came head of the therapeutic chemistry laboratory at the Pasteur Institute. Also in 1937 Bovet discovered com pounds that neutralized some of the un pleasant symptoms of allergic manifes tations, such as a stuffed or runny nose. Since these symptoms are thought to arise through the production in the body of a compound called histamine, a drug that counters the symptoms is an an tihistamine. Bovet’s first clear-cut chemi cal antihistamine was pyrilamine, intro duced in 1944. Numerous antihistamines have been developed since, and while none of them cures an allergy, they tend to suppress the symptoms and make life more bearable for the sufferer. During the early 1950s it occurred to some drug manufacturers that allergic manifestations resembled some of the symptoms of colds and antihistamine drugs were therefore widely touted as cold relievers (not cold cures). For a while they proliferated into a national fad, as a few years afterward the tran quilizers, first introduced by Wilkins [1320], were to do. Thirdly, Bovet developed a method of using curare in surgery. Curare is an alkaloid found in the root of several South American shrubs. It paralyzes the muscles (including those of the heart, so that it is a quick poison) and is, indeed, the prototype of the “mysterious South American poison” so beloved by mystery writers. With the proper modification and in the proper doses, it relaxes the muscles without killing. Such relaxation, in conjunction with anesthesia, is very useful in surgery. For his work on antihistamines and on 822
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curare, Bovet was awarded the 1957 Nobel Prize in medicine and physiology. In 1947 he had accepted a post as head of a pharmacological laboratory at a research institution in Rome and even tually became an Italian citizen. [1326] TINBERGEN, Nikolaas Dutch zoologist Born: The Hague, April 15, 1907 Tinbergen received his Ph.D. from the University of Leiden in 1932 and taught there until 1949, at which time he moved to Oxford. In 1936, he met Lorenz [1271], grew interested in ethology, and worked par ticularly with the instincts and behav ior of sea gulls. He noted that animals fighting others of the same species tend to suspend aggression when the loser adopts a posture indicating surrender. For that reason quarrels over food and mates rarely lead to death or even seri ous wounding; such quarrels merely de cide who wins and who loses in an all- but-harmless ritualistic fashion. Tinber gen suspects that the use of long-range weapons that increasingly divorces fight ers from those with whom they fight has acted to cancel out the possibility of sur render and increases the death and de struction of human warfare. In 1973 he shared the Nobel Prize for physiology and medicine with Lorenz and Karl von Frisch [1110]. [1327] JENSEN, Johannes Hans Daniel German physicist Born: Hamburg, June 25, 1907 Jensen, a gardener’s son, obtained his Ph.D. at the University of Hamburg in 1932, joined the faculty in 1936, and was then director of the Institute for Theoretical Physics at that university. In 1949 he took up a professorial post at Heidelberg. He advanced the notion of nuclear shells in 1949 independently of Goep- pert-Mayer [1307] and in 1955 co authored a book on the subject with her. They shared the 1963 Nobel Prize in physics with Wigner [1260]. [1328] MAUCHLY, John William American engineer Born: Cincinnati, Ohio, August 30, 1907 Died: January 8, 1980 Mauchly obtained his Ph.D. at Johns Hopkins University in 1932, then went on to teach physics at Ursinus College in Collegeville, Pennsylvania, in 1933. He took a post at the University of Pennsyl vania in 1941 and there he taught elec trical engineering. In 1944, in partnership with Eckert [1431], he established a company for design and manufacturing of electronic digital computing machinery. He pro duced the first practical electronic digital computer, ENIAC, in 1946. It was an enormous, energy-guzzling device but it was a wonder in its time and represented a coming-to-life of Babbage’s [481] dream.
Almost at once the electronic com puter began to improve and grow more versatile, more compact, and more inex pensive. Mauchly helped develop the first UNIVAC in 1951, the first data processor to use magnetic tape. Then came the solid state devices, pio neered by Shockley [1348], which pro ceeded to change computers out of all recognition before their first decade had been completed. [1329] McMILLAN, Edwin Mattison American physicist
nia, September 18, 1907 McMillan, the son of a physician, graduated from California Institute of Technology in 1928 and obtained his Ph.D. in 1932 at Princeton University. In that year he joined the faculty of the University of California. There he was involved in the early work with Lawrence [1241] on the cy clotron. By the 1940s the cyclotron had grown so large and the speeding particles had been driven into so great a velocity that their mass increased noticeably. This is the “relativistic mass increase,” the in crease of mass with velocity that was 823
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first predicted by Lorentz [839] and then shown by Einstein [1064] to be a natural consequence of the assumptions upon which the theory of relativity was based. The increase of mass slowed the parti cles slightly and threw out of synchro nization the little pushes that were sup posed to continue to speed up the parti cles. As a result, the energy that could be imparted to a charged particle could not be raised above a certain maximum and so the cyclotrons of the early 1940s had reached their limits. In 1945 McMillan was one of those who devised a method whereby the in creasing mass could be allowed for. The periodic pushes of the electric field then remained in synchronization and syn chrocyclotrons were built that could reach higher energy levels than ordinary cyclotrons. (Similar devices were de signed in Great Britain and the Soviet Union where the same advance in tech nique was made independently.) The energies of charged particles are measured in electron volts. Energies in the many million-electron-volt range (MEV) were reached in the 1940s. In the 1950s further improvements, sugges ted by Kerst’s [1367] betatron, were in troduced and the most powerful particle accelerators, the proton synchrotrons, were devised. The billion-electron-volt range (bev) was reached and the beva- tron, used by Segre [1287] to form anti protons, carries that fact in its name, for it reaches energies of 5 or 6 bev. Instru ments put in action in Geneva and in Brookhaven, Long Island, in the early 1960s, produce particles with energies of over 30 bev. McMillan’s most dramatic discovery, however, had come before World War II. When Fermi [1243] first began bombarding uranium with neutrons, he was trying to form the element beyond uranium, the element with atomic num ber 93. He thought he had been able to detect such an element, but this was an error. The work of Hahn [1063] showed that uranium fission was taking place in stead.
In 1940 McMillan and Abelson [1383], experimenting with fission, dis covered a beta-particle activity with a half life of 2.3 days. When they traced this down, they announced on June 8, 1940, that it was element number 93 (produced in very small quantities by a uranium reaction with neutrons that did not involve fission). Since uranium had been named for the planet Uranus by Klaproth [335], the new element 93, lying beyond uranium, was named nep tunium for Neptune, the planet beyond Uranus. This was the first of the trans uranium elements. Since the particular neptunium isotope that had been discovered emitted beta particles, it had to become an element that was higher in the periodic table by one, according to the rules worked out by Soddy [1052]. In 1940 element 94 was detected and named plutonium after Pluto, the planet beyond Neptune. One of the moving spirits in this new phase of the investigation was Seaborg [1372]. McMillan had left the university for war work on radar, sonar, and, of course, the atomic bomb. Seaborg car ried on after the war, isolating numer ous still-higher transuranium elements. McMillan, after the war, went on to work with high-energy accelerators, as already mentioned, and after 1946 he was professor of physics at the Univer sity of California. McMillan and Seaborg shared the 1951 Nobel Prize in chemis try for their work on the new elements beyond uranium. For his discovery of the synchrocyclotron, McMillan received the 1963 Atoms for Peace award, shar ing it with Veksler [1324], who had made the same discovery independently. [1330] DUNNING, John Ray American physicist Born: Shelby, Nebraska, Septem ber 24, 1907 Died: Key Biscayne, Florida, Au gust 25, 1975 Dunning, the son of a grain merchant who was also an amateur radio engineer, graduated from the Nebraska Wesleyan University with highest honors in 1929 and went on to get his Ph.D. from Co lumbia University in 1934. After that, he spent a year in Europe meeting with the 824
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TELLER [1332]
great nuclear physicists and returned to join the physics department at Columbia. He built that institution’s first cyclotron in 1936. He became dean of the Faculty of Engineering and Applied Science at Columbia in 1950. He was one of those who were at the meeting, in 1939, at which Bohr [1101] announced Meitner’s [1060] theory on uranium fission. Of the number of physi cists who instantly went to work to confirm that theory, Dunning was the first, by a hair, to succeed. Bohr, furthermore, reasoned from theory that of the two natural uranium isotopes, it would be uranium-235 (much the rarer of the two) that under went fission. In early 1940 Dunning managed to separate small quantities of uranium-235 and the common variety, uranium-238, and showed that Bohr was right and that it was the former that un derwent fission. Dunning went on to develop the gas diffusion method of separating the ura nium isotopes in quantity. It was the first successful method and is still the most useful. In recognition of this work, the Atomic Energy Commission paid Dun ning $30,000 in lieu of patent royalties. [1331] TODD, Alexander Robertus, Baron
Scottish chemist Born: Glasgow, October 2, 1907 Todd graduated from the University of Glasgow in 1929, then studied at the University of Frankfurt-am-Main and at Oxford University. He obtained a doc torate at the former in 1931 and at the latter institution, under Robinson [1107], in 1933. In 1934 he joined the faculty of the University of Edinburg and in 1938 accepted a professorship of chemistry at the University of Manchester. At Manchester, Todd concerned him self with the chemistry of the nucleic acids and the nucleotides. Here he took up where Levene [980] had left off. Levene had deduced the formulas of the nucleotides (the small units out of which the large nucleic acid molecules were built up) and Todd proceeded to synthe size all the naturally occurring nucleotide components of the nucleic acids. In doing so, he found that the structures as prescribed by Levene did indeed produce compounds that were identical with those obtained from nucleic acids. This confirmed Levene’s deductions. In 1944 Todd went on to Cambridge University and, while there, synthesized naturally occurring compounds related to the nucleotides. In 1947 he synthesized the compounds adenosine diphosphate and adenosine triphosphate (ADP and ATP), which are of crucial importance in the handling of energy by the body, as Lipmann [1221] showed. In the 1950s he synthesized several coenzymes with nu cleotide-like structure. Todd’s work on these compounds made certain the general chemistry of the nucleic acids. The way was clear for M. H. F. Wilkins [1413], James Dewey Watson [1480], and Crick [1406], who, in the 1950s, were then able to work out the fine detail of nucleic acid structure. Todd was knighted in 1954 and for his work on nucleotides was awarded the 1957 Nobel Prize in chemistry. In 1962 he was created a life peer as Baron Todd of Trumpington. [1332] TELLER, Edward Hungarian-American physicist
ary 15, 1908 Teller, the son of prosperous Jewish parents, obtained his Ph.D. at the Uni versity of Leipzig in Germany in 1930. While a student, he lost his right foot in a streetcar accident. He did postdoctorate work, almost in evitably, with Niels Bohr [1101] in Co penhagen, then lectured at Gottingen. He, like his countryman Szilard [1208], left because of Hitler. He went first to Denmark, then England, and finally to the United States, where he arrived in 1935. He was naturalized in 1941, and during World War II was engaged in work on the uranium-fission bomb (the so-called atomic bomb or A-bomb) at Los Alamos, New Mexico. In the early 1950s, when some scien- 825
[1333] LANDAU
LANDAU [1333]
lists, notably Oppenheimer [1280], shrank from the development of the hy drogen-fusion bomb (the H-bomb) in view of the power of the nuclear weap ons that already existed, Teller was one of those who argued most strenuously in favor of such development. Further more, he devised something (the details of which are shrouded in the mists of se curity) that made the device practical. For that reason, he is called the father of the H-bomb. The first H-bomb explosion took place in 1952 on a Pacific island. The Soviet Union quickly followed with an explo sion of its own and in a decade the force of these bombs was escalated to 50 megatons; that is, to the equivalent of 50 million tons of TNT, or 2500 times the power of the bomb exploded over Hiroshima. Teller’s evidence went furthest in de nying Oppenheimer his security clear ance in 1954, and this cost Teller consid erable loss of respect among a large por tion of the scientific community, who were also bothered by the fact that he seemed not frightened by the weapon he fathered. He minimized the effect of fall out, advocated testing in the atmosphere, and argued that a nuclear war need not be disastrous. In this he stood opposed to the large group of scientists, of whom Pauling [1236] was perhaps the most distin guished, who were by no means as calm in the face of the thermonuclear danger. In 1956 Teller became professor of physics at the University of California and in 1962 he received the Fermi award. [1333] LANDAU, Lev Davidovich Soviet physicist Born: Baku, Azerbaijan, January 22, 1908 Died: Moscow, April 1, 1968 Landau, the son of an engineer father and a physician mother, studied at the University of Baku and moved on to the University of Leningrad (the city and university having been newly renamed after Lenin’s death). He entered the uni versity in 1924 and graduated in 1927. After a professorial appointment at the University of Kharkov, he trav eled abroad, visiting Bom [1084] at Got tingen and attending lectures given by Heisenberg [1245] in Leipzig. He then spent some years in Copenha gen, which Niels Bohr [1101] had single- handedly converted into a Mecca for theoretical physicists, and went on to Cambridge, where he studied under Ernest Rutherford [996]. In 1931 Lan dau returned to the Soviet Union. He re ceived his doctorate at Kharkov in 1934. In 1935 he pioneered the mathe matical treatment of magnetic domains, small regions in substances such as iron, in which all the atomic magnets are lined up in a given direction. It is this that gives rise to ferromagnetism, the strongest variety of magnetism. In 1937 he was appointed head of a section at the Institute for Physical Problems in Moscow, where Kapitza [1173] was working, and Landau’s interest turned to low-temperature phenomena, too. In 1938 he was arrested as a German spy by an increasingly repressive Stalin regime and was released only by the per sonal intervention of Kapitza. In 1941 Landau produced a theoretical treatment of the properties of helium II in terms of quantum mechanics, which he modified in 1947 and which is the most satis factory to date. In the 1950s he turned to helium-3, a rare isotope of helium, and predicted startling properties for it, too, at very low temperatures. The verification of these properties is a cur rent goal in extreme low-temperature work. For his studies in this direction Landau was awarded the 1962 Nobel Prize in physics. This came at a time of personal tragedy. On January 7, 1962, Landau was nearly killed in an automobile accident near Moscow, breaking eleven bones and fracturing his skull. After that, he hov ered between life and death. Indeed, the story is that he passed the line ordinarily separating life and death several times but was brought back by drastic methods each time. Finally, in October 1964, he was re 826
[1334] BARDEEN
BAWDEN [1337]
leased from the hospital, but he never really recovered and, inevitably, death finally came. [1334] BARDEEN, John American physicist
23, 1908 Bardeen graduated from the Univer sity of Wisconsin in 1928 and obtained his Ph.D. under Wigner [1260] at Princeton University in 1936. He was Wigner’s second American doctoral can didate. He taught at the University of Minnesota from 1938 to 1941, then, after working for the navy as a physicist during World War II, he joined the Bell Telephone Laboratories in 1945. He shared with Shockley [1348] and Brattain [1250] the glory of the discov ery of the transistor and the 1956 Nobel Prize in physics. After 1951 he was pro fessor of physics at the University of Illi nois, working on superconductivity. For the theories he developed explain ing various aspects of superconductivity, he shared the Nobel Prize in physics in 1972. He was the first person to win two Nobel Prizes in physics. [1335] ALFVEN, Hannes Olof Gosta Swedish astrophysicist
30, 1908 Alfven’s work is primarily in the mat ter of magnetic fields and how plasmas react with them. (Plasma is matter that is hot enough for the atoms to break down into charged fragments.) In 1939 he published a theory of magnetic storms and the aurora. In it he calculated the motions of particles along magnetic lines of force, which could be used to deal with some aspects of sunspots and cos mic rays. His work on magnetohydrodynamics (the movement of plasma in magnetic fields) is fundamental to the attempts made in the last thirty years to confine plasma at ultra-high temperatures and generate controlled fusion reactions. In addition, magnetohydrodynamics finally explained the problem that had smashed Laplace’s [347] nebular hypothesis by showing how, through electromagnetic interaction, the major portion of the an gular momentum of the solar system could be concentrated in the compara tively insignificant fraction of the total mass that makes up the planets. For his work on magnetohydrody namics, Alfven shared the 1970 Nobel Prize for physics with Neel [1285]. [1336] KOZYREV, Nikolai Alexandro vich (koh-zee'rev) Soviet astronomer Born: St. Petersburg (now Lenin grad), 1908 Kozyrev graduated from the Univer sity of Leningrad in 1928 and by 1931 had taken a post at the astronomical ob servatory at Pulkovo, ten miles south of the city. In 1937 he was imprisoned for some reason and not released till 1948. Kozyrev’s most dramatic observation came in 1958 in connection with the moon. The moon, ever since Galileo’s [166] first telescopic observations, had gener ally been considered a cold, dead world, where no change took place or was possible, except for that which was impressed from without (as by meteoric bombardment). Kozyrev, however, managed to catch the formation of a cloud or mist in the crater Alphonsus, and a spectrum taken of the area at that time made it appear that a cloud of carbon particles had been emitted.
This was the first observation of some thing like volcanic activity on the moon and heightened the interest with which mankind was approaching the day when human beings would walk our satellite. [1337] BAWDEN, Sir Frederick Charles English plant pathologist
August 18, 1908 Obtaining his master’s degree from Cambridge in 1930, Bawden began work Download 17.33 Mb. Do'stlaringiz bilan baham: 
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