dispersion strengthened composite
21North America — North American. the northern continent of the Western Hemisphere, extending from Central America to the Arctic Ocean. Highest point, Mt. McKinley, 20,300 ft. (6187 m); lowest, Death Valley, 276 ft. (84 m) below sea level. 400,000,000 including… …
22Mesopotamia, history of — ▪ historical region, Asia Introduction history of the region in southwestern Asia where the world s earliest civilization developed. The name comes from a Greek word meaning “between rivers,” referring to the land between the Tigris and… …
23Military history of France during World War II — History of France …
24Glass microsphere — For microspheres made of other materials, see Microsphere. SEM micrograph of a glass microsphere in concrete Glass microspheres are microscopic spheres of glass manufactured for a wide variety of uses in research, medicine, consumer goods and… …
25Glass transition — The liquid glass transition (or glass transition for short) is the reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle state into a molten or rubber like state …
