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resonance, in chemistry

(Encyclopedia)resonance, in chemistry: see chemical bond. ...

electromagnet

(Encyclopedia)CE5 Electromagnet electromagnet, device in which magnetism is produced by an electric current. Any electric current produces a magnetic field, but the field near an ordinary straight conductor is ...

Wüthrich, Kurt

(Encyclopedia)Wüthrich, Kurt, 1938–, Swiss chemist, Ph.D. Univ. of Basel, 1964. Wüthrich has been on the faculty at the Swiss Federal Institute of Technology since 1969 and at the Scripps Research Institute, La...

fluxional molecules

(Encyclopedia)fluxional molecules, molecules that exhibit rapid intramolecular rearrangements among their component atoms. As in structural isomerism and tautomerism (see isomer; tautomer), fluxional compounds main...

radiology

(Encyclopedia)radiology, branch of medicine specializing in the use of X rays, gamma rays, radioactive isotopes, and other forms of radiation in the diagnosis and treatment of disease. X ray machines and fluoroscop...

Ramsey, Norman Foster, Jr.

(Encyclopedia)Ramsey, Norman Foster, Jr., 1915–2011, American physicist, b. Washington, D.C., Ph.D. Columbia, 1940. A member of the faculty at Harvard from 1947 and the Higgins professor of physics from 1966 (eme...

electric and magnetic units

(Encyclopedia)electric and magnetic units, units used to express the magnitudes of various quantities in electricity and magnetism. Three systems of such units, all based on the metric system, are commonly used. On...

Bloembergen, Nicolaas

(Encyclopedia)Bloembergen, Nicolaas nēˈkəläs blo͞omˈbĕrgən, –bûrgən [key], 1920–2017, American physicist, b. Dordrecht, the Netherlands. Educated in the Netherlands, he began work at Harvard in 1946, ...

weber, unit of magnetic flux

(Encyclopedia)weber vāˈbər, wē–, wĕbˈər [key] [for W. E. Weber], abbr. Wb, unit of magnetic flux in the mks system of weights and measures; 1 Wb is equal to 1 volt-second. The weber per square meter, calle...

diagnosis

(Encyclopedia)diagnosis, determination of the nature of a disease or ailment. A clinical diagnosis is based on the medical history and physical examination of the patient: it may be confirmed with X-Rays, CAT Scans...