Abstract: Method of forming a (CFX)n containing adsorbent composition by combining a fine particle (CFX)n starting material with a non-fluorinated carbonaceous material prior to the formation of a solid body and intermediate materials employed in conducting the method.

Abstract: The invention relates to an apparatus for determining the frost point of a gas containing a very small amount of water. The apparatus comprises (I) compartment A made of a good heat conductor; (II) an inlet for the gas to be measured, which inlet is provided on compartment A; and (III) a heater for adjusting the temperature in compartment A, and a temperature sensor. The apparatus further comprises (IV) compartment B which is adjacent to compartment A. At least part of compartment B is made of a poor heat conductor. Further, the apparatus comprises (V) a hole at the interface between compartments A and B and (VI) a reflector mirror having a temperature sensor. The reflector mirror is provided on compartment B in such a way as to cover the hole is connected thermally to a freeze source in such a way that the temperature of the reflector mirror can be varied from room temperature to at least -80.degree. C.

Abstract: A method of determining the dew point of a gas containing a very small amount of water using (1) a reflector mirror the temperature of which can be varied from room temperature down to at least -80.degree. C.; (2) a source of condensed rays of light for irradiating the reflector mirror; and (3) a light recovering device that detects changes in scattered light due to condensation on the reflector mirror by exposing the mirror to the gas. The method comprises cooling the mirror and detecting the temperature at which the scattered light has a maximum intensity; slowly raising the temperature and detecting the temperature at which the scattered light has a minimum intensity and repeating the cycle until the temperature at which the intensity is a maximum and the temperature at which the intensity is a minimum are almost the same.

Abstract: A method of cleaning a reflector mirror in an optical dew point meter that measures the dew point or frost point of a sample gas by a process including the steps of bringing the sample gas into contact with the reflector mirror whose temperature is variable, projecting condensed rays of light or laser light onto said reflector mirror, and detecting the change in the intensity of scattered light and/or reflected light on account of the dew or frost formed on said reflector mirror, characterized by bringing a CO.sub.2 gas or a CO.sub.2 containing gas into contact with the reflector while the latter is in a cooled state, thereby condensing CO.sub.2 on the surface of the reflector mirror, and the subsequent step of heating the reflector mirror to vaporize the CO.sub.2 is dischosed.