Glass volatility

Va.por Pressure. Vitreous sihca is a highly refractory glass. Volatilization is significant only at elevated temperatures (Fig. 1), occurring under a... 

Corrosion is caused by condensation of glass volatiles that have flowed into the burner region. If the burner is colder than the condensation point of the volatiles, the volatiles will condense on the burner and chemically attack the burner. This phenomenon is common for water-cooled burners since they are relatively cold and typically high momentum. High-momentum burners generally induce a flow pattern that promotes movement of the furnace gases back to the burner tip. To minimize this problem, non-water-cooled, low-velocity burners are recommended.11... 

The apparatus consisted of a U-shape glass volatilization pipe preheated to a designed temperature, a nose-only exposure unit containing six mice, a glass wool trap (packed with 0.5 g of glass wool fiber) that sequestered the vaporized test compound, and a vacuum system that created negative pressure and pulled the air through the... 

DIFFUSION-CONTROLLED MELT(GLASS)-VOLATILE ISOTOPE EXCHANGE... 

Figure 11. Simulated steam atmosphere system for viscous glass volatilization test.

Some of the constituents of glass volatilize during operation (e g. silica, borate, and alkali metals). These constituents will likely foul or poison the electrode catalyst or interact in an undesirable manner with other cell components... 

Carius tube A thick-walled glass lube originally used in the Carius method but used in any reaction involving volatile materials. 

All glassware should be scrupulously clean and, for most purposes, dry before being employed in preparative work in the laboratory. It is well to develop the habit of cleaning all glass apparatus immediately after use the nature of the dirt will, in general, be known at the time, and, furthermore, the cleaning process becomes more difficult if the dirty apparatus is allowed to stand for any considerable period, particularly if volatile solvents have evaporated in the meantime. 

Note. 3. All glassware of the distillation apparatus must be rinsed before use with a dilute solution of triethylamine Or another volatile amine in diethyl ether. Traces of acid on the glass walls may cause isomerization to H2C=CH-C(OCH3)=C(CH3)(OC2H5). 

Table 1 shows that most acryflcs have low glass-transition temperatures. Therefore, in copolymers they tend to soften and flexibHize the overall composition. Plasticizers also lower the transition temperature. However, unlike incorporated acryflc comonomers, they can be lost through volatilization or extraction. 

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