| 摘要 |
1,017,940. Gas analysis. O. H. DRAGER [trading as DRAGERWERK HEINR.& BERNH. DRAGER], June 29, 1964 [June 27, 1963], No. 26867/64. Heading G1B. A tube for detecting the presence of hydrogen in a gas sample contains a first material 1 to absorb water vapour, a catalyst 2 to oxidize hydrogen at normal temperatures, and a third material 3 to indicate the presence of water vapour caused by oxidation of hydrogen. The first material is in the form of a molecular sieve and preferably comprises hopcalite or another catalyst which oxidizes any carbon monoxide present and absorbs water. As a catalyst for oxidation of hydrogen finely divided metallic deposits of platinum, palladium, or nickel on a carrier of silica gel may be employed. The third material comprises a mixture of selenium dioxide and sulphuric acid monohydrate on a ceramic carrier e.g. sinteredaluminate silicate, the reagent being activated by vapors of petroleum spirit or pentane. This reagent has a yellow colour changing to red in the presence of water and it is found that the graph of hydrogen concentration against colour change zone length of the material 3 is linear. |
