the glass, which depend on the relative temperatures of the

contents of the equipment and the external surroundings.
Provided borosilicate glass is not subjected to rapid change in temperature, creating undue adj. 過(guò)度的，過(guò)分的；不適當的；未到期的thermal shock, it can be operated safely at temperatures up to 450°F (232°C). The normal limiting factor is actually the gasket ['ɡæskit] n. 墊圈；襯墊；束帆索material. The degree of

thermal shock (usually defined as sudden chilling ['tʃiliŋ] adj. 寒冷的；冷漠的；使人恐懼的；令人寒心的；[俚]呱呱叫的n. 寒冷；冷卻) which it can withstand depends on many factors, for example: stresses

due to operating conditions; stresses imposed in supporting

the equipment; the wall thickness of the glass, etc. It is

therefore undesirable adj. 不良的；不受歡迎的；不合需要的to give an overall figure but, as a

general guide, sudden temperature changes of up to about

 216°F (120°C) can be accommodated .

At sub-zero adj. 零下的；嚴寒的temperatures, the tensile adj. [物]拉力的；可伸長(cháng)的；可拉長(cháng)的strength of borosilicate