- Wyckoff , Ralph Walter Graystone
- (1897–1994) American crystallographer and electron microscopistWyckoff was born in Geneva, New York, and graduated from Hobart College. He obtained his PhD from Cornell in 1919. Between 1919 and 1938 Wyckoff worked first in the Geophysical Laboratory, New York, and then at the Rockefeller Institute before transferring to the Lederle Laboratories in 1938. He then worked at the University of Michigan (1943–45) and the National Institute of Health (1945–59). He was appointed to the chair of physics and microbiology at the University of Arizona in 1959.While at the Rockefeller Institute Wyckoff purified various viruses, including that causing equine encephalomyelitis, using an ultracentrifuge. The pure preparations of encephalomyelitis virus were used to develop a killed-virus vaccine which proved effective against the epidemic that was affecting horses in America. This success led to a program for producing typhus vaccine.In 1944 Wyckoff entered into an unusual and profitable collaboration with the astronomer-turned-biophysicist Robley Williams. Wyckoff was using the electron microscope to photograph viruses but found, as did other virologists of the time, that the amount of information conveyed about the size and shape of the virus was strictly limited.Wyckoff discussed with Williams the problem of determining the size of a speck of dust that had fallen onto a specimen and been photographed with it. To an astronomer the solution was obvious, for it is a standard procedure to measure the heights of lunar mountains from the length of the shadow cast by them and knowledge of the angle of the incident light source. The problem was to make viruses cast shadows. They placed the specimen in a vacuum together with a heated tungsten filament covered with gold. This vaporized and coated the side of the specimen nearest the filament, leaving a ‘shadow’ on the far side.This technique of ‘metal shadowing’ opened a new phase in the study of viruses allowing better estimates to be made of their size and shape, as well as revealing details of their structure.
Scientists. Academic. 2011.
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Wyckoff, Ralph Walter Graystone — ▪ American chemist born Aug. 9, 1897, Geneva, N.Y., U.S. died Nov. 3, 1994, Tucson, Ariz. American research scientist, a pioneer in the application of X ray methods to determine crystal structures and one of the first to use these methods… … Universalium
Ralph Walter Graystone Wyckoff — Infobox Scientist name = PAGENAME box width = image width =150px caption = PAGENAME birth date = August 9, 1897 birth place = Geneva, New York death date = November 3, 1994 death place = Tucson, Arizona residence = citizenship = nationality =… … Wikipedia
Ralph Walter Graystone Wyckoff — (* 9. August 1897 in Geneva (New York); † 3. November 1994 in Tucson, Arizona) war ein US amerikanischer Kristallograph. Wyckoff war von 1919 bis 1927 im geophysikalischen Labor an der Carnegie Institution of Washington tätig. Von 1927 bis 1937… … Deutsch Wikipedia
Ralph Wyckoff — Ralph Walter Graystone Wyckoff (* 9. August 1897 in Geneva (New York); † 3. November 1994 in Tucson, Arizona) war ein US amerikanischer Kristallograph. Wyckoff war von 1919 bis 1927 im geophysikalischen Labor an der Carnegie Institution of… … Deutsch Wikipedia
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