A transistorised liquid helium capacity level gauge

✍ Scribed by Ya.I. Rosenberg; V.G. Kasatkin

• Publisher: Elsevier Science
• Year: 1964
• Tongue: English
• Weight: 169 KB
• Volume: 4
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(64)90112-2

✦ Synopsis

The para concentration of the hydrogen was measured with a heat conductivity gas analyser using a bridge circuit. 3 The gas analyser was calibrated with the sensitive cells thermostatted at 77 ° K, using four fixed points which fell on a straight line: 25 per cent parahydrogen (T---300 ° K); 50-8 per cent (77 ° K); 62-6 per cent (63 ° K); and 99"8 per cent.

The considerable difference of the reaction rate constant from that reported by Larsen et al. ~ is explained by the catalytic property of the inner walls of the vessel. The wall material or chance dirt collecting inside the Dewar can act as catalysts. The degree of working of the walls can also affect the catalytic power. In order to approach the conditions which will apply in the laboratory or in industry, no steps were taken in the experiments described to clean the vessel before filling. Experiments carried out showed that the rate constant differed only insignificantly from the mean given above for different samples of vessel.

In conclusion I would like to thank A. B. Fradkov for his help and co-operation in carrying out the work.

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