Tuesday, May 5, 2009

Zewail, Ahmed


Egyptian-American scientist won the Nobel Prize for chemistry today for demonstrating that a rapid laser technique can observe the motion of atoms in a molecule as they occur during a chemical reaction. Ahmed Zewail was born in February 26, 1946, in Egypt where he grew up, Zewail received both his Bachelor of Science and his master's degrees from Alexandria University Alexandria. He began his professional career as an undergraduate trainee at Shell Corporation in Alexandria in 1966. After continued studies in the U.S.A. he graduated for Ph.D. in 1974 at the University of Pennsylvania. After the completion of his Ph.D., he went to the University of California, Berkeley, as an IBM research fellow. Zewail was appointed to the faculty at Caltech in 1976 at the age of 30 as an assistant professor of chemical physics. In 1982 he was tenured, as he became a full professor, and in 1990 was honored by the first Linus Pauling Chair at Caltech. At the age of 52, Zewail won the “Banjamin Franklin” prize after his latest scientific achievements known as the femto_second which is the smallest part of he second, he received the prize at a lavish ceremony attended by some 1,500 scientists, students, officials and figures, including former US Presidents Jimmy Carter and Gerald Ford. In 1999, Dr. Ahmed Zewail, a laser expert was nominated for the Nobel Prize for Chemistry and by that he is the first Egyptian to be nominated for this honourable prize. Dr. Zewail is the first originally Arab Muslim scientist to win such prize since Naguib Mahfouz, who won the literature prize in 1988, and late President Anwar Sadat, who shared the peace prize in 1978. But he is the first to take one of the prestigious awards for science. The Nobel carries an award of nearly one million dollars. Dr.Zewail currently holds both Egyptian and American Nationality. He has a family of four children and is married to Dema Zewail, a physician in public health (UCLA). His scientific family over the past 20 years consists of some 150 post-doctoral research fellows, graduate students and visiting associates. He lives in San Marino, California. Ahmed Zewail currently is the Linus Pauling Chair Professor of Chemistry and Professor of Physics at the California Institute of Technology, and Director of the NSF Laboratory for Molecular Sciences (LMS). Zewail's current research is devoted to developments of ultrafast lasers and electrons for studies of dynamics in chemistry and biology. In the field of femtochemistry, developed by the Caltech group, the focus is on the fundamental, femtosecond (10-15 second) processes in chemistry and in related fields of physics and biology.

Bohr, Aage Niels (1922- ),


Danish physicist and Nobel laureate, born in Copenhagen. The son of Niels Bohr, he assisted his father on the atomic bomb project at Los Alamos, New Mexico, during World War II. He then joined the Institute for Theoretical Physics in Copenhagen, devoting his attention to the inner structure of the atom.
In 1954 he wrote his doctoral thesis at the University of Copenhagen. It dealt with a collective motion theory of the atomic nucleus that he had developed with the United States physicist Ben R. Mottelson at the suggestion of the US physicist James Rainwater. The theory helped to explain many nuclear properties by showing that nuclear particles can vibrate and rotate so as to distort the shape of the nucleus from the expected spherical symmetry into an ellipsoid. Bohr, Mottelson, and Rainwater received the 1975 Nobel Prize for Physics for this work.
In 1963 Bohr became Director of the institute, now renamed in honour of his father. He resigned in 1970 to devote more time to research, but in 1975 he became Director of the Nordic Institute of Theoretical Atomic Physics, which shares research and facilities with the Niels Bohr Institute

Sakharov, Andrei Dmitriyavich


was the Soviet physicist most responsible for developing that nation's hydrogen bomb. He later became an internationally known social philosopher and an advocate for human right and world harmony. Harrison E. Salisbury's introduction to Sakharov's manifesto for world harmony, Progress, Coexistence, and Intellectual Freedom (1968), described Sakharov as an "Oppenheimer, Jeller, and Hans Bethe all rolled into one," who grew into a philosopher and social architect on a world scale. Graduating with honors from Moscow State University (1942), Sakharov showed intellectual talents so remarkable that he was exempted from military service to continue his studies during World War II (1939-1945). In 1945, he became an associate at the P. N. Le-bedev Physics Institute in Moscow, where he earned a Ph.D. in physical and mathematical sciences (1947). In the Soviet Union, this degree was generally reserved for more experienced scientists. Between 1948 and 1956, Sakharov was engaged in secret research on nuclear weapons specifically directing development of the hydrogen bomb. In 1953, he became the youngest scientist ever to be elected to the prestigious Soviet Academy of Sciences. In the early 1960's, while he continued his research on the theoretical aspects of controlled fusion at the Lebedev Institute, Sakharov and his wife, Yelena Bonner, became outspoken critics of human rights violations in the Soviet Union and around the world. By the mid-1960's, Sakharov's research interest had changed from nuclear physics to the nature of the universe In 1968, The New York Times printed Sakharov's Progress, Coexistence, and Intellectual Freedom. In this declaration, Sakharov laid out his plan for world peace and progress based on cooperation between the world's superpowers, with an emphasis on human rights and intellectual freedom. In 1970, Sakharov and two other physicists formed the Committee for Human Rights to give a stronger voice to their efforts to stop human rights violations within the Soviet Union. In 1975, Sakharov was awarded the Nobel Prize for Peace for his work in promoting world harmony and opposing violence
Reacting to his ceaseless criticism, the Soviet government arrested Sakharov in 1980, exiling him from Moscow to Gorki (now Nizhniy Novgorod, Russia), then an industrial center closed to foreigners. He was released in 1986 and returned to Moscow where he became part of a changed and changing government. In 1989, Sakharov was elected to the newly formed Soviet legislature, the Congress of People's Deputies. Sakharov's Memoirs, published in 1990 after his death, describe his life as a scientist and human rights advocate.

Hall, Lioyd Augustus (1894-1971)


was an African American chemist and inventor. He was granted more than 100 patents for processes used in food manufacturing and packaging, including his development of curing salts, condiments, spices, and flavors used in the meatpacking industry. Born in Elgin, Illinois, Hall received a B.S. degree in 1916 from Northwestern University. He worked briefly as a sanitary chemist at the Chicago Board of Health and as president and chemical director of Chemical Products Corporation. He then served as chief chemist and director of research at Grifrith Laboratories Inc. in Chicago from 1925 to 1946. Hall, a member of several professional societies, was the first African American to serve on the Board of Directors of the American Institute of Chemists, which presented him with its Honor Scroll Award of the Institute's Chicago Chapter in 1956. He also served on the board of the Institute of Food Technologists, which he co founded.

De Broglie, Louis Victor (1892-1987),


a French physicist, proposed the theory explaining the wave properties of electrons in 1924. His work greatly advanced the early understanding of quantum theory, the study of the parts of the atom and their behavior. In 1924, existing quantum theory stated that light waves sometimes behave like particles. Using mathematical logic, de Broglie reasoned that the particles, in turn, have wavelike properties. De Broglie's theory of "matter waves," which sent physicists everywhere thinking in new and unexpected direction, became the foundation for a new field of study-wave mechanics.
Proof of de Broglie's theory came in 1927 in experiments by physicists Clinton j. Davisson and Lester Halbert Germer, working with slow electrons, and by G. P. Thomson, working with fast electrons. For his vision, de Broglie received the 1929 Nobel Prize for physics and the Henri Poincare Medal of the Academie des Sciences. After receiving a degree in history from the Sorbonne in 1909, de Broglie took up his real interest, receiving a "license" in science from the University of Paris in 1913. During World War 1(1914-1918), he served in the radiotelegraph branch of the French Engineering Corps at the wireless station of the Eiffel Tower. Afterward, de Brogue resumed his scientific study at his brother's physics laboratory. Born into a noble French family, de Broglie was known as Prince Louis Victor Pierre Raymond de Broglie throughout his life. His ancestors served French kings in war and diplomacy from the time of Louis XIV. De Broglie's brother Maurice, also a physicist, was known for his research in nuclear physics, X rays, and radioactivity. While pursuing his lifelong interest in research, de Broglie taught theoretical physics at the Henri Poincare' Institute in Paris. In 1943, he founded the Center for Studies in Applied Mathematics at the institute to help physicists and mathematicians work together. Along with his brother, de Broglie was named to the French High Commission on Atomic Energy in 1945, and he also was a member of the Academie Francaise, which oversees French language and literature. De Broglie was elected to a number of prestigious international scientific societies and was appointed permanent secretary of the French Academy of Sciences in 1942.

Chadwick, Sir James (1891-1974),


British physicist and Nobel laureate, who is best known for his discovery in 1932 of one of the fundamental particles of matter, the neutron, a discovery that led directly to nuclear fission and the atomic bomb. He was born in Manchester and educated there at Victoria University. In 1909 he began working under the physicist Ernest Rutherford. At the end of World War I he went to the University of Cambridge with Rutherford, with whom he continued a fruitful collaboration until 1935. In that year Chadwick became professor at the University of Liverpool. From 1948 to 1958 he was Master, and from 1959 a Fellow, of Gonville and Caius College, University of Cambridge.
Chadwick was one of the first in Britain to stress the possibility of the development of an atomic bomb and was the chief scientist associated with the British atomic bomb effort. He spent much of his time from 1943 to 1945 in the United States, principally at the Los Alamos Scientific Laboratory (now the Los Alamos National Laboratory), New Mexico. A Fellow of the Royal Society, Chadwick received the 1935 Nobel Prize for Physics and was knighted in 1945.

Moseley, Henry Gwyn Jeffreys (1887-1915),


English experimental physicist who achieved the first experimental identification of the atomic number and nuclear charge of an element. Born in Weymouth, Dorset, Moseley came from a distinguished family of scientists. After studying physics at Oxford, he joined Ernest Rutherford at Manchester. His initial work was on beta emission from radium, but he soon moved on to the study of X-ray spectra, using the technique of X-ray diffraction developed by W. H. Bragg and his son, W. L. Bragg. Ever since Mendeleev's proposal of the periodic table in 1869, chemists had striven to explain the fact that the chemical properties of the elements are a periodic function of their atomic weights. By means of X-ray diffraction, Moseley established, in 1913, a relationship between the frequencies of X-ray emission lines and what he concluded must be the atom's nuclear charge, thereby confirming the suggestion of A. van der Broek that the nuclear charge indicated an element's position in the periodic table. Moseley thus provided an experimental basis for equating nuclear charge with what he called atomic number. From now on it became possible to predict, from gaps in the series of X-ray frequencies, the existence of missing elements in the periodic table. Moseley moved back to Oxford to continue his work there, but was killed two years later in the battle of Sari Bair during the Gallipoli campaign.