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Prout, William

(Encyclopedia)Prout, William, 1785–1850, English chemist and physician. Prout's hypothesis, advanced in 1815–16, suggested that atomic weights of elements are multiples of that of hydrogen and that elements are...

tartar

(Encyclopedia)tartar or argol ärˈgəl [key], impure potassium hydrogen tartrate deposited as a crust in fermenting vessels during wine making. When purified, it yields cream of tartar. Tartar is the chief natural...

zinc sulfate

(Encyclopedia)zinc sulfate, chemical compound ZnSO4, a very water soluble, transparent, colorless, crystalline compound. It is commonly used as the heptahydrate, ZnSO4·7H2O, and is commonly called white vitriol; i...

atropine

(Encyclopedia)atropine ătˈrəpēn, –pĭn [key], alkaloid drug derived from belladonna and other plants of the family Solanaceae (nightshade family). Available either as the tincture or extract of belladonna, or...

myoglobin

(Encyclopedia)myoglobin mīˌəglōˈbĭn [key], protein molecule isolated from the cells of vertebrate skeletal muscle that is both a structural and functional relative of hemoglobin, the oxygen-transport protein ...

osmium

(Encyclopedia)osmium ŏzˈmēəm [key], metallic chemical element; symbol Os; at. no. 76; at. wt. 190.23; m.p. 3,045±30℃; b.p. 5,027±100℃; sp. gr. 22.57 at 20℃; valence usually +0 to +8. Osmium is a very ha...

Ashkin, Arthur

(Encyclopedia)Ashkin, Arthur, 1922–2020, American physicist, b. Brooklyn, N.Y., Ph.D. Cornell, 1952. Ashkin worked for four decades at Bell Laboratories, retiring in 1992. Ashkin researched microwaves, nonlinear ...

hippopotamus

(Encyclopedia)hippopotamus, herbivorous, river-living mammal of tropical Africa. The large hippopotamus, Hippopotamus amphibius, has a short-legged, broad body with a tough gray or brown hide. The male stands about...

virology

(Encyclopedia)virology, study of viruses and their role in disease. Many viruses, such as animal RNA viruses and viruses that infect bacteria, or bacteriophages, have become useful laboratory tools in genetic studi...

biochemistry

(Encyclopedia)biochemistry, science concerned chiefly with the chemistry of biological processes; it attempts to utilize the tools and concepts of chemistry, particularly organic and physical chemistry, for elucida...