silica refractory
81Converting (metallurgy) — Converting is a term used to describe a number of metallurgical smelting processes. The most commercially important use of the term is in the treatment of molten metal sulfides to produce crude metal and slag, as in the case of copper and nickel… …
82Ceramic glaze — Composite body, painted, and glazed bottle. Dated 16th century. From Iran. New York Metropolitan Museum of Art. Glaze is a layer or coating of a vitreous substance which has been fired to fuse to a ceramic object to color, decorate, strengthen or …
83Forest glass — The term Forest glass or the German name Waldglas is given to late Medieval glass produced in North Western Europe from about 1000 1700AD using wood ash and sand as the main raw materials and made in factories known as glass houses in forest… …
84mullite — /mul uyt/, n. a rare clay mineral, aluminum silicate, Al6Si2O13, produced artificially during various melting and firing processes: used as a refractory. Also called porcelainite. [1924; after MULL, source of the rocks in which it was first… …
85pottery — /pot euh ree/, n., pl. potteries. 1. ceramic ware, esp. earthenware and stoneware. 2. the art or business of a potter; ceramics. 3. a place where earthen pots or vessels are made. [1475 85; POTTER1 + Y3] * * * I One of the oldest and most… …
86spaceflight — /spays fluyt /, n. the flying of manned or unmanned spacecraft into or in outer space. Also, space flight. [1945 50; SPACE + FLIGHT1] * * * Introduction flight beyond Earth s atmosphere. This article deals with the basic concepts associated with …
87transition element — Chem. any element in any of the series of elements with atomic numbers 21 29, 39 47, 57 79, and 89 107, that in a given inner orbital has less than a full quota of electrons. Also called transition metal. [1920 25] * * * Any chemical element with …
88thorium processing — Introduction preparation of the ore for use in various products. Thorium (Th) is a dense (11.7 grams per cubic centimetre), silvery metal that is softer than steel. It has a high melting temperature of approximately 1,750° C (3,180°… …
89Alkali metal — Group → 1 ↓ Period 2 3 Li 3 …
90Timeline of chemical elements discoveries — The discovery of the elements known to exist today is presented here in chronological order. The elements are listed generally in the order in which each was first defined as the pure element,[clarification needed] as the exact date of discovery… …
