Tritium Transport Properties

Tables 2,3, and 4 outline many of the physical and thermodynamic properties ofpara- and normal hydrogen in the sohd, hquid, and gaseous states, respectively. Extensive tabulations of all the thermodynamic and transport properties hsted in these tables from the triple point to 3000 K and at 0.01—100 MPa (1—14,500 psi) are available (5,39). Additional properties, including accommodation coefficients, thermal diffusivity, virial coefficients, index of refraction, Joule-Thorns on coefficients, Prandti numbers, vapor pressures, infrared absorption, and heat transfer and thermal transpiration parameters are also available (5,40). Thermodynamic properties for hydrogen at 300—20,000 K and 10 Pa to 10.4 MPa (lO " -103 atm) (41) and transport properties at 1,000—30,000 K and 0.1—3.0 MPa (1—30 atm) (42) have been compiled. Enthalpy—entropy tabulations for hydrogen over the range 3—100,000 K and 0.001—101.3 MPa (0.01—1000 atm) have been made (43). Many physical properties for the other isotopes of hydrogen (deuterium and tritium) have also been compiled (44).

Ferrichrome iron transport in the enteric bacteria affords an experimentally feasible model for mechanistic studies. The ligand is rugged and can be labeled to high specific activity by microwave discharge activation of tritium gas. The labile ferric ion can be replaced with chromium to yield the kinetically stable isostructural chromic complex, chromichrome (61). Assuming this analog has the transport properties of the iron complex, its 3H counts would be an index of the behavior of... 

Transport properties, 152,279t Transposes of matrices, 1 52 Trickv plurals, 71—72 Trigonometric functions, 152—154 Triple bonds in chemical formulas, 260 Tris as multiplying prefix, 234—235 Tritium, 258, 259... 

Layers are formed on many locations of the plasma facing wall tiles but also on areas with no direct plasma ion impact ( remote areas ). It turns out that understanding of the tritium-retention requires the understanding of the erosion of carbon, its local and global transport within the device and the details of the deposition mechanisms being responsible for the layer properties. 

An unresolved issue related to the use of a beryllium, or any solid material, as a first wall is the issue of mixed-materials. Although the properties of beryllium may lend themselves to its use in a particular environment, those properties can change dramatically as material from other locations in the machine is eroded, transported and then deposited on the beryllium plasma facing surfaces. Such mixed-material surfaces can dominate the rate of long-term tritium accumulation within a device and may severely restrict its operational lifetime. 

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