Ruby-red glass

Ruby laser Ruby red glass Ruetschi vacancy model... 

The final stage is to control the temperature programme in order to promote the growth of the silver droplets to the size required to produce the yellow colour, in the same way as the production of ruby red glasses. 

The photosensitive nature of selenium makes it useful in devices that respond to the intensity of light, such as photocells, light meters for cameras, xerography, and electric eyes. Selenium also has the ability to produce electricity directly from sunlight, making it ideal for use in solar cells. Selenium possesses semiconductor properties that make it useful in the electronics industry, where it is a component in some types of solid-state electronics and rectifiers. It is also used in the production of ruby-red glass and enamels and as an additive to improve the quality of steel and copper. Additionally, it is a catalyst (to speed up chemical reactions) in the manufacture of rubber. 

An important application of copper(I) oxide is in antifouling paints for steel, wood, and other materials exposed to sea water. Other applications include manufacture of ruby-red glass and preparation of miscellaneous copper salts. It also is used as a reducing agent in brazing pastes as a fungicide in photocells and as a catalyst. 

Make a concentrated solution of anthracene in hot acetone. To about 2 ml. of this solution add a cold concentrated acetone solution of picric acid drop by drop, and note the formation of a red coloration which becomes deeper on further addition of the acid. If excess of picric acid is added, however, the solution becomes paler in colour, and this is to be avoided if possible. Boil to ensure that both components are in solution and then transfer to a small porcelain basin or watch-glass ruby-red crystals of anthracene picrate separate out on cooling. The product, however, is often contaminated with an excess of either anthracene or of picric acid, which appear as yellowish crystals. 

Arsenic disulfide (AsS) is also known as ruby arsenic because it is a reddish-orange powder. It is used as a depilatory agent, a paint pigment, and a rat poison and to make red glass and fireworks. 

Selenium is also used to impart a ruby-red color to glass, and to neutralize the green color in glass which is due to the presence of iron. 

Formula weight 158.11. Ruby-red bipyramlds, readily soluble in water. Etches glass vessels in which it is stored. Crystal structure tetragonal (space group Cfh). 

Cadmium Sulphide. CdS sp. gr. 4.8 m.p. 1750 C. A constituent of some ruby-coloured glass, of some yellow enamels, and of Cd-Se red ceramic colours which can be fired at temperatures up to about 850°C. Sintered CdS can be used as a photoconductive ceramic. 

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