Ultrasound-assisted reductive dissolution of CeO2 and PuO2 in the presence of Ti particles.

PuO2 is considered an important material for current and future nuclear fuel; however it is a very refractive compound towards dissolution. Among other techniques, its reprocessing can be performed via complexing dissolution in concentrated and boiling nitric acid containing hydrofluoric acid, or via oxidant dissolution in the presence of reagents with redox couples having high potentials such as Ce(iv)/Ce(iii), or Ag(ii)/Ag(i). Reductive dissolution can be performed under softer conditions and is considered an alternative to these methods which may suffer from several drawbacks (corrosion, effluent management, compatibility with nuclear waste disposal, etc.

Self-assembly of silk-collagen-like triblock copolymers resembles a supramolecular living polymerization.

We produced several pH-responsive silk-collagen-like triblocks, one acidic and two alkaline. At pH values where the silk-like block is uncharged the triblocks self-assemble into filaments. The pH-induced self-assembly was examined by atomic force microscopy, light scattering, and circular dichroism.