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In Situ High Pressure Hydrogen Tribological Testing of Common Polymer Materials Used in the Hydrogen Delivery Infrastructure
Published on: March 31, 2018
Phase boundary of hot dense fluid hydrogen
Kenji Ohta1,2, Kota Ichimaru1, Mari Einaga1
1Center for Science and Technology under Extreme Conditions, Osaka University, Toyonaka, Osaka 560-8531, Japan.
Abstract:
We investigated the phase transformation of hot dense fluid hydrogen using static high-pressure laser-heating experiments in a laser-heated diamond anvil cell. The results show anomalies in the heating efficiency that are likely to be attributed to the phase transition from a diatomic to monoatomic fluid hydrogen (plasma phase transition) in the pressure range between 82 and 106 GPa. This study imposes tighter constraints on the location of the hydrogen plasma phase transition boundary and suggests higher critical point than that predicted by the theoretical calculations.
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