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gadolinium

(Encyclopedia)gadolinium gădəlĭnˈēəm [key], metallic chemical element; symbol Gd; at. no. 64; at. wt. 157.25; m.p. 1,312℃; b.p. 3,233℃; sp. gr. 7.898 at 25℃; valence +3. Gadolinium is a malleable, ducti...

phosphorylation

(Encyclopedia)phosphorylation, chemical process in which a phosphate group is added to an organic molecule. In living cells phosphorylation is associated with respiration, which takes place in the cell's mitochondr...

flotation process

(Encyclopedia)flotation process, in mineral treatment and mining, process for concentrating the metal-bearing mineral in an ore. Crude ore is ground to a fine powder and mixed with water, frothing reagents, and col...

orchard grass

(Encyclopedia)orchard grass or cocksfoot, widely distributed perennial grass (Dactylis glomerata) native to Eurasia and N Africa and extensively naturalized in the United States. It is cultivated as a hay grass mor...

liquefaction

(Encyclopedia)liquefaction, change of a substance from the solid or the gaseous state to the liquid state. Since the different states of matter correspond to different amounts of energy of the molecules making up t...

Mar, John Erskine, 1st (or 6th) earl of

(Encyclopedia)Mar, John Erskine, 1st (or 6th) earl of, d. 1572, regent of Scotland. As Lord Erskine he was keeper of Edinburgh and Stirling castles, a source of much political strength. In the struggle between the ...

crystal

(Encyclopedia)CE5 Types of crystal crystal, a solid body bounded by natural plane faces that are the external expression of a regular internal arrangement of constituent atoms, molecules, or ions. The formation...

pharming

(Encyclopedia)pharming färˈmĭng [key], the use of genetically altered livestock, such as cows, goats, pigs, and chickens, to produce medically useful products. In pharming, researchers first create hybrid genes ...

hedge

(Encyclopedia)hedge, ornamental or protective barrier composed of shrubs or small trees growing in close rows. The plants may be allowed to grow naturally or may be trimmed to various heights and shapes (see topiar...

stele

(Encyclopedia)stele stēˈlē [key], slab of stone or terra-cotta, usually oblong, set up in a vertical position, for votive or memorial purposes. Upon the slabs were carved inscriptions accompanied by ornamental d...