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Boltzmann, Ludwig

(Encyclopedia)Boltzmann, Ludwig lo͝otˈvĭkh bôltsˈmän [key], 1844–1906, Austrian physicist, b. Vienna, educated at Univ. of Vienna. He began teaching (1869) at Graz Univ. In 1873 he became mathematics profes...

Ziegler, Karl

(Encyclopedia)Ziegler, Karl tsēˈglər [key], 1898–1973, German chemist. Educated at the Univ. of Marburg, he taught at Heidelberg and Halle and for a short period at the Univ. of Chicago. He became director of ...

ribose

(Encyclopedia)ribose rīˈbōs [key], monosaccharide carbohydrate of universal distribution in living tissue, found in ribonucleic acid (RNA; see nucleic acid), free nucleotides, and various coenzymes. Its close re...

alkane

(Encyclopedia)CE5 Alkanes alkane ălˈkān [key], any of a group of aliphatic hydrocarbons whose molecules contain only single bonds (see chemical bond). Alkanes have the general chemical formula CnH2n+2. An al...

fermentation

(Encyclopedia)fermentation, process by which the living cell is able to obtain energy through the breakdown of glucose and other simple sugar molecules without requiring oxygen. Fermentation is achieved by somewhat...

vacuum

(Encyclopedia)vacuum, theoretically, space without matter in it. A perfect vacuum has never been obtained; the best human-generated vacuums contain less than 100,000 gas molecules per cc, compared to about 30 billi...

protein

(Encyclopedia)protein, any of the group of highly complex organic compounds found in all living cells and comprising the most abundant class of all biological molecules. Protein comprises approximately 50% of cellu...

dextrin

(Encyclopedia)dextrin, any one of a number of carbohydrates having the same general formula as starch but a smaller and less complex molecule. They are polysaccharides and are produced as intermediate products in t...

Lehn, Jean-Marie

(Encyclopedia)Lehn, Jean-Marie zhäNˈ-märēˈ lĕN [key], 1939–, French chemist, Ph.D. Univ. of Strasbourg, 1963. A professor at Louis Pasteur Univ. (1970–78) and the Collège de France (1979–), Lehn did gr...

butadiene

(Encyclopedia)butadiene byo͞otˌədīˈēn [key], colorless, gaseous hydrocarbon. There are two structural isomers of butadiene; they differ in the location of the two carbon-carbon double bonds in the butadiene m...