A Hybrid of gamma–type layered zirconium phosphate (γ–ZrP) as a host material and ruthenium as an activator was used as the catalyst for H₂ generation from NH₃ gas. The hybrids were prepared through two processes, ion exchange and exfoliation. In the case of the ion exchange hybrid, the amount of Ru was around one–tenth of the ion exchange capacity, and the activity was relatively low. On the other hand, in the exfoliation treatment, colloidal Ru was fixed on the zirconium phosphate nanosheets, enhancing the activity for H₂ generation at a relatively low temperature range starting from 400℃. Synchrotron XAFS measurements confirm that γ–ZrP with exfoliation treatment provided a better hybridization field for colloidal Ru species. Additionally, the chemical states of Ru were analyzed by in–situ XAFS, revealing that metallic Ru species showed a superior effect for H₂ generation.

　In this study, the effect of carbonation on the durability of hardened cement paste under marine environment was investigated. Non–carbonated and carbonated samples were immersed in seawater for 91 days. The non–carbonated samples reacted with seawater and cement hydrates to form ettringite, which can cause cracks in the hardened body, and magnesium silicate hydrate (M–S–H), which can weaken the structure. On the other hand, carbonation dissolved calcium aluminate hydrate, Ca(OH)₂, and C–S–H, and neither ettringite nor M–S–H was formed after immersion in seawater in the carbonated samples consisting mainly of CaCO₃, alumina gel, and silica gel.