content of impurities

См. также в других словарях:

• Stoneware — a vitreous or semivitreous ceramic ware of fine texture, made primarily from nonrefactory fire clay. [Standard Terminology Of Ceramic Whiteware and Related Products. ASTM Standard C242.] Its maturation temperature ranges from about 1200°C to 1315 …   Wikipedia

• metallurgy — metallurgic, metallurgical, adj. metallurgically, adv. metallurgist /met l err jist/ or, esp. Brit., /meuh tal euhr jist/, n. /met l err jee/ or, esp. Brit., /meuh tal euhr jee/, n. 1. the technique or science of working or heating metals so as… …   Universalium

• rare-earth element — /rair errth /, Chem. any of a group of closely related metallic elements, comprising the lanthanides, scandium, and yttrium, that are chemically similar by virtue of having the same number of valence electrons. Also called rare earth metal. [1955 …   Universalium

• lead processing — Introduction       preparation of the ore for use in various products.       Lead (Pb) is one of the oldest metals known, being one of seven metals used in the ancient world (the others are gold, silver, copper, iron, tin, and mercury). Its low… …   Universalium

• cereal processing — Introduction       treatment of cereals (cereal) and other plants to prepare their starch for human food, animal feed, or industrial use.        Nutrient composition of selected raw cereal grains (per 100 grams)Cereals, or grains, are members of… …   Universalium

• environmental works — ▪ civil engineering Introduction       infrastructure that provides cities and towns with water supply, waste disposal, and pollution control services. They include extensive networks of reservoirs, pipelines, treatment systems, pumping stations …   Universalium

• Polyethylene terephthalate — PETE redirects here. For the first name, see Peter (disambiguation). For other uses, see Pete (disambiguation). Polyethylene terephthalate fibre IUPAC name …   Wikipedia

• Iron — Fe redirects here. For other uses, see Fe (disambiguation). This article is about the chemical element. For other uses, see Iron (disambiguation). manganese …   Wikipedia

• Crystal oscillator — A miniature 4 MHz quartz crystal enclosed in a hermetically sealed HC 49/US package, used as the resonator in a crystal oscillator. A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal …   Wikipedia

• coal mining — Coal was very important in the economic development of Britain. It was used as fuel in the factories built during the Industrial Revolution and continued to be important until the 1980s. The main coalfields are in north east England, the north… …   Universalium

• petroleum refining — Introduction  conversion of crude oil into useful products. History Distillation of kerosene and naphtha       The refining of crude petroleum owes its origin to the successful drilling of the first oil well in Titusville, Pa., in 1859. Prior to… …   Universalium