Fused glasses

Hermetic Seal—an impervious seal made by the fusion of metals of ceramics, which prevents the passage of gas or moisture. The seal can be achieved by brazing, soldering, welding, fusing glass or ceramics. 

Prepare a fused glass tube 2-3 cm long and about 1 cm in diameter. Carefully introduce the end of the tube into the upper part of the bag and fasten the bag to the tube with thread. Store the bag in a beaker in water. 

A mixture of perfluorobenzene (0.30 mL), H20, d = 1.403. 0 26 mL), and McCN (10 mL) was heated at 140 C in a fused glass ampule for 10 h. The mixture was then filtered, the filtrate was poured into 0.1 M NaflSO, (100 mL), acidified with H2S04, and extracted with Et20. The ethereal solution was dried ( CaCf) and the solvent was removed in vacuo to give the crude product that was purified by TLC (CHC13) ... 

Figure 3.7. Raman spectra of K-feldspar diaplectic glass (38 GPa), fused glass, and crystal [31],...

The density variation in Fig. 3.14a is similar to that of Si02 glass. However, tlie maximum density increase (2.2%) at 24 GPa is smaller tlian tliat for Si02 glass (11 % Okuno et al. [26]). At higher shock pressure, tlie density redecreases to almost the value of fused glass. 

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