Modelling of geochemical reactions and experimental cation exchange in MX 80 bentonite.

Bentonites are widely used for waste repository systems because of their hydrodynamic, surface and chemical-retention properties. MX 80 bentonite (bentonite of Wyoming) contains approximately 85% Na/Ca-montmorillonite and 15% accessory minerals. The dominant presence of Na/Ca-montmorillonite in this clay mineral could cause it to perform exceptionally well as an engineered barrier for a radioactive waste repository because this buffer material is expected to fill up by swelling the void between canisters containing waste and the surrounding ground.

[Rehabilitation of the paralyzed face by hypoglossal-facial nerve anastomosis. An analysis of 7 cases].

After facial nerve injury, in cerebello-pontine tumors surgery, hypoglossal-facial anastomosis is the most common procedure, to rehabilite a paralysed face, if direct facio-facial graft is not possible. This procedure must be done, in a second time, during the next year and followed with a specific reeducation. In seven patients operated between 1985 and 1996, we performed clinical evaluation and electrophysiological examination.