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organometallic chemistry

(Encyclopedia)organometallic chemistry, the reactions and use of a class of compounds (R-M) that contain a covalent bond between carbon and metal. They are prepared either by direct reaction of the metal with an or...

surface chemistry

(Encyclopedia)surface chemistry, study of chemical reactions in which the reactants are first adsorbed onto a surface medium (see adsorption) that then acts as a catalyst for the reaction; after the reaction the pr...

magnetic resonance imaging

(Encyclopedia)magnetic resonance imaging (MRI), noninvasive diagnostic technique that uses nuclear magnetic resonance to produce cross-sectional images of organs and other internal body structures. The patient lies...

electron paramagnetic resonance

(Encyclopedia)electron paramagnetic resonance: see magnetic resonance. ...

resonance, in acoustics

(Encyclopedia)resonance, in acoustics: see vibration. ...

nuclear magnetic resonance

(Encyclopedia)nuclear magnetic resonance: see magnetic resonance. ...

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...

mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

ash, in chemistry

(Encyclopedia)ash, in chemistry, solid residue of combustion. The chemical composition of an ash depends on that of the substance burned. Wood ash contains metal carbonates (e.g., potassium carbonate) and oxides fo...

formula, in chemistry

(Encyclopedia)formula, in chemistry, an expression showing the chemical composition of a compound. Formulas of compounds are used in writing the equations (see chemical equations) that represent chemical reactions....