| 摘要 |
PURPOSE:To prevent pollution and to reduce operating costs by using a synthetic isoparaffin hydrocarbon cleaning agent which does not freeze at specified low temperature and does not boil at specified high temperature, as a common medium for both a cryostat and a thermostat. CONSTITUTION:A synthetic isoparaffin hydrocarbon available on the market, having a pour point of -70 deg.C or less and a boiling point of 210 to 265 deg.C, is used as a common medium at low and high temperatures. A testing device is sealed to avoid inflammation and to prevent the medium from being released into the atmosphere. In addition to sealing, the liquid phase portion of the medium may be replaced by an inert gas. The synthetic hydrocarbon has a low pour point, and therefore good flowability and low viscosity, so that little of adheres to a subject to be tested as the subject goes out of a cryostat; even if it is released into the atmosphere, its effects on the environment are almost negligible. |
