Enameling

When glazing is done on metallic surfaces, the process is called enameling. 

It also refers to glazing on top of a glazed surface. When the organic component in a paint is replaced by glass, the paint is known as enamel paint. 

1 Estimate the mean firing shrinkage between particles, Al, when the mean particle diameter is 1 p and the measured firing shrinkage is 44%. Assume body centered cubic packing of particles. 

2 The diametral shrinkage is 16.3%. Calculate the volume shrinkage, assuming the shrinkage is isotropic. 

3 Given below is the number of grains intersecting on a line of 5 cm when found at a magnification lOOx  

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For temperatures up to 100°, a water bath or steam bath is generally employed. The simplest form is a beaker or an enamelled iron vessel mounted on a suitable stand water is placed in the vessel, which is heated by means of a flame. This arrangement may be used for non-inflammable liquids or for refluxing liquids of low boiling point. Since numerous liquids of low boiling point are highly inflammable, the presence of a naked flame will introduce considerable risk of fire. For such liquids a steam bath or an electrically-heated water bath, provided with a constant-level device, must be used. If the laboratory is equipped with a... 

The presence of fluorine as a soluble fluoride in drinking water to the extent of 2 ppm may cause mottled enamel in teeth, when used by children acquiring permanent teeth in smaller amounts, however, fluorides are added to water supplies to prevent dental cavities. 

The salts have been used for centuries to produce brilliant and permanent blue colors in porcelain, glass, pottery, tiles, and enamels. It is the principal ingredient in Sevre s and Thenard s blue. A solution of the chloride is used as a sympathetic ink. Cobalt carefully used in the form of the chloride, sulfate, acetate, or nitrate has been found effective in correcting a certain mineral deficiency disease in animals. 

Selenium is used in Xerography for reproducing and copying documents, letters, etc. It is used by the glass industry to decolorize glass and to make ruby-colored glasses and enamels. It is also used as a photographic toner, and as an additive to stainless steel. 

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