2018 | AFC ACCOMPLISHMENTS 56 The sample reaction chamber was placed inside a tube furnace and brought to the desired temperature. Once at temperature, the manifold was filled with a known pressure of hydrogen.After the hydrogen had equilibrated in the manifold, the sample chamber was opened to the hydrogen.The amount of hydrogen absorbed by the material was measured by the change in hydrogen pressure through the ideal gas law. Pressure was measured using an MKS Baratron capacitance manometer. Incremental aliquots of hydrogen were provided to the manifold after pressure stabiliza- tion was achieved.Aliquoting was performed until the hydrogen pres- sure in the sample chamber reached a value of 320 torr, at which point the measurement was terminated. Figure 2: Pressure-composition- temperature isotherm for hydrogen absorption of U3Si2 at 350°C. Hydriding was terminated at 320 torr of H2 and absorbed hydrogen corresponding to a H/U ratio of 0.084.