Glass hydration

Lanford, W. A. (1986), Glass hydration A method of dating glass objects, Science 166, 975-976. 

Lanford. W A. Glass Hydration A Method of Daring Glass Objects." Science. 196,... 

Ag/AgCl, 0.1M HCl/hydrated layer/dry glass/hydrated layer/sample... 

A CFSE CFSE MgO - glass A120, - glass hydrate - glass... 

Silicates in Ceramics and Glass Hydrated silicate polymers are important in the ceramics industry. A colloidal dispersion of particles in a liquid is called a sol. The sol can be poured into a mold and, following removal of some of the... 

The product is sometimes contaminated with silicic acid from the glass of the condenser this may be removed by filtration. All corlcs should be covered with tin foil to avoid attack by the hydrazine hydrate. 

Hydrazine hydrate of 95-100 per cent, concentration is a commercial product. The 40-60 per cent, solution may be concentrated to 80-85 per cent, strength by distillation with xylene in an all-glass apparatus. 

Precipitated (hydrated) siUca reacts vigorously with fluorosulfuric acid to give siUcon tetrafluoride [7783-61-1] (21), but glass (qv) is not attacked in the absence of moisture (20). Alkali and alkaline-earth metal chlorides are readily converted to fluorosulfates by treatment with fluorosulfuric acid (7,13,22,23). 

Examples include luminescence from anthracene crystals subjected to alternating electric current (159), luminescence from electron recombination with the carbazole free radical produced by photolysis of potassium carba2ole in a fro2en glass matrix (160), reactions of free radicals with solvated electrons (155), and reduction of mtheiiium(III)tris(bipyridyl) with the hydrated electron (161). Other examples include the oxidation of aromatic radical anions with such oxidants as chlorine or ben2oyl peroxide (162,163), and the reduction of 9,10-dichloro-9,10-diphenyl-9,10-dihydroanthracene with the 9,10-diphenylanthracene radical anion (162,164). Many other examples of electron-transfer chemiluminescence have been reported (156,165). 

Amorphous silica, ie, silicon dioxide [7631-86-9] Si02, does not have a crystalline stmcture as defined by x-ray diffraction measurements. Amorphous silica, which can be naturally occurring or synthetic, can be either surface-hydrated or anhydrous. Synthetic amorphous silica can be broadly divided into two categories of stable materials (1) vitreous silica or glass (qv), which is made by fusing quart2 at temperatures greater than approximately 1700°C (see Silica, vitreous silica), and microamorphous silica, which is discussed herein. 

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