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compost
(Encyclopedia)compost, substance composed mainly of partly decayed organic material that is applied to fertilize the soil and to increase its humus content; it is often used in vegetable farming, home gardens, flow...hardening
(Encyclopedia)hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly. Sometimes small ar...liming
(Encyclopedia)liming līmˈĭng [key], application to the soil of calcium in various forms, generally as ground limestone, but also as marl, chalk, shells, or hydrated lime. Lime benefits soil by neutralizing acidi...lewisite
(Encyclopedia)lewisite lo͞oˈəsītˌ [key], liquid chemical compound used as a poison gas. Like mustard gas and nitrogen mustard, it is a blistering agent; when inhaled, it is a powerful respiratory irritant. The...drainage, in agriculture
(Encyclopedia)drainage, in agriculture, the removal of excess water from the soil, either by a system of surface ditches, or by underground conduits if required by soil conditions and land contour. Diesel or centri...melamine
(Encyclopedia)melamine mĕlˈəmēnˌ [key], common name for 2,4,6-triamino-1,3,5-triazine. Melamine is a trimer (see polymer) of cyanamide, H2NC≡N, and is synthesized from calcium carbide. It condenses with form...Scheele, Karl Wilhelm
(Encyclopedia)Scheele, Karl Wilhelm kärl vĭlˈhĕlm shāˈlə [key], 1742–86, Swedish chemist, b. Stralsund. He is known as the discoverer of many chemical substances. He was a pharmacist in Stockholm, in Uppsa...Ostwald, Wilhelm
(Encyclopedia)Ostwald, Wilhelm vĭlˈhĕlm ôstˈvält [key], 1853–1932, German physical chemist and natural philosopher, b. Riga, Latvia. He was professor of chemistry and director of the chemical laboratory (18...wart
(Encyclopedia)wart, circumscribed outgrowth of the skin caused by a filterable virus that is readily transmitted. Warts may appear anywhere on the skin but are most common on the hands. Sexually transmitted disease...mucopolysaccharide
(Encyclopedia)mucopolysaccharide myo͞oˌkəpŏlēsăkˈərīd [key], class of polysaccharide molecules, also known as glycosaminoglycans, composed of amino-sugars chemically linked into repeating units that give a...Browse by Subject
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