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Stein, William Howard

(Encyclopedia)Stein, William Howard, 1911–80, American biochemist, b. New York City, Ph.D. Columbia, 1937. Stein was a professor at the Rockefeller Institute for Medical Research (now Rockefeller Univ.) from 1937...

silver nitrate

(Encyclopedia)silver nitrate nīˈtrāt [key], chemical compound, AgNO3, a colorless crystalline material that is very soluble in water. The most important compound of silver, it is used in the preparation of silve...

solder

(Encyclopedia)solder sŏdˈər [key], metal alloy used in the molten state as a metallic binder. The type of solder to be used is determined by the metals to be united. Soft solders are commonly composed of lead an...

nitrogen

(Encyclopedia)nitrogen nīˈtrəjən [key], gaseous chemical element; symbol N; at. no. 7; interval in which at. wt. ranges 14.00643–14.00728; m.p. −209.86℃; b.p. −195.8℃; density 1.25 grams per liter at ...

medlar

(Encyclopedia)medlar mĕdˈlər [key], small deciduous tree (Mespilus germanica) of the family Rosaceae (rose family), native to Europe and Asia. It has luxuriant foliage and large white or pinkish flowers; in the ...

Metchnikoff, Élie

(Encyclopedia)Metchnikoff, Élie ālēˈ mĕchˈnĭkôf [key], 1845–1916, Russian biologist. He studied in Russia and Germany, lectured at the Univ. of Odessa, and, after working with Pasteur in Paris, became (19...

leaching

(Encyclopedia)leaching, method of extraction in which a solvent is passed through a mixture to remove some desired substance from it. A simple example is the passage of boiling water through ground coffee to dissol...

Reichstein, Tadeus

(Encyclopedia)Reichstein, Tadeus tädĕˈo͞osh rīkhˈshtīn [key], 1897–1996, Swiss organic chemist, b. Vlotslavsk, Russia (now Włocławek, Poland), educated at the technical school in Zürich, where he also t...

tautomer

(Encyclopedia)tautomer tôˈtəmər [key], one of two or more structural isomers that exist in equilibrium and are readily converted from one isomeric form to another. Of the various types of tautomerism that are p...

clubroot

(Encyclopedia)clubroot, disease of cabbages, turnips, radishes, and other plants belonging to the family Cruciferae (or Brassicaceae; mustard family). It is induced by a plasmodial slime mold that attacks the roots...