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rheostat

(Encyclopedia)rheostat rēˈəstătˌ [key], device whose resistance to electric current depends on the position of some mechanical element or control in the device. Typically a rheostat consists of a resistance el...

Cytoxan

(Encyclopedia)Cytoxan sītŏkˈsĭn [key], trade name for the drug cyclophosphamide, used to inhibit growth of tumors and rapidly proliferating cells. It is used in the treatment of leukemia, Hodgkin's disease, and...

cold frame

(Encyclopedia)cold frame, in horticulture, sun-heated board frame covered with a removable top of glass or other transparent material and sunk into the ground. The top may be solid or slatted or screened for shade....

inorganic chemistry

(Encyclopedia)inorganic chemistry, the study of all the elements and their compounds with the exception of carbon and its compounds, which fall under the category of organic chemistry. Inorganic chemistry investiga...

dialysis

(Encyclopedia)dialysis dīălˈĭsĭs [key], in chemistry, transfer of solute (dissolved solids) across a semipermeable membrane. Strictly speaking, dialysis refers only to the transfer of the solute; transfer of t...

coal mining

(Encyclopedia)coal mining, physical extraction of coal resources to yield coal; also, the business of exploring for, developing, mining, and transporting coal in any form. Coal has been historically important indus...

ash, in chemistry

(Encyclopedia)ash, in chemistry, solid residue of combustion. The chemical composition of an ash depends on that of the substance burned. Wood ash contains metal carbonates (e.g., potassium carbonate) and oxides fo...

spermaceti

(Encyclopedia)spermaceti spûrˈməsēˈtē [key], solid waxy substance, white, odorless, and tasteless, separated from the oils obtained from the sperm whale (see sperm oil) and other marine mammals. A mixture of ...

heat

(Encyclopedia)heat, nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. The study of heat and its relationship ...

cinnamon

(Encyclopedia)cinnamon, name for trees and shrubs of the genus Cinnamomum of the family Lauraceae (laurel family). True cinnamon spice comes from the Ceylon or Sri Lanka cinnamon (C. verum or C. zeylanicum), now cu...