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disinfectant

(Encyclopedia)disinfectant, agent that destroys disease-causing microorganisms and their spores. Disinfectants, or germicides, are sometimes considered to be substances applied to inanimate bodies, whereas antisept...

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...

ferrous sulfate

(Encyclopedia)ferrous sulfate or iron (II) sulfate, chemical compound, FeSO4. It is known as the monohydrate, FeSO4·H2O; the tetrahydrate, FeSO4·4H2O; the pentahydrate, FeSO4·5H2O; and the heptahydrate, FeSO4·7...

pectin

(Encyclopedia)pectin, any of a group of white, amorphous, complex carbohydrates that occur in ripe fruits and certain vegetables. Fruits rich in pectin are the peach, apple, currant, and plum. Protopectin, present ...

photoengraving

(Encyclopedia)photoengraving, photomechanical process in the graphic arts, used principally for reproducing illustrations. The subject is photographed, and the image is recorded on a sensitized metal plate, which i...

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...

Skou, Jens Christian

(Encyclopedia)Skou, Jens Christian, 1918–2018, Danish chemist, M.D. Univ. of Copenhagen, 1944, Ph.D. Univ. of Aarhus, 1954. Skou was on the faculty at the Univ. of Aarhus, Denmark, from 1947 until he retired in 1...

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...

Szent-Gyorgyi, Albert von

(Encyclopedia)Szent-Gyorgyi, Albert von älˈbĕrt fən sĕntˌ-dyörˈdyĭ [key], 1893–1986, American biochemist, b. Hungary, M.D. Univ. of Budapest, 1917; Ph.D. Cambridge, 1927. After teaching at the universiti...

technetium

(Encyclopedia)technetium tÄ•knēˈshÄ“É™m [key] [Gr. technetos=artificial], artificially produced radioactive chemical element; symbol Tc; at. no. 43; mass no. of most stable isotope 98; m.p. 2,200℃; b.p. 4,877â„...