Publications by authors named "Ryo Takahama"

Herein, CoN, CuN, and NiN complexes with a 14-membered ring hexaazamacrocycle ligand HHAM were synthesised as precursors for ORR and CORR catalysts a one-pot, gram-scale synthesis procedure, which involved microwave heating for only 10 min. Detailed structures of the obtained 14MR-MN complex were revealed by single-crystal X-ray diffraction measurements.

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Nonplatinum metal (NPM) catalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs) have been developed; however, NPM catalysts still need to be improved in terms of both their catalytic activity and durability. To overcome these problems, an Fe active site contained within a more compact ligand than conventional, porphyrinic, 16-membered ring ligands, or more specifically, a hexaaza macrocyclic ligand with a 14-membered ring (14MR), was developed. In this study, the durability of the Fe-14MR complex was compared to that of Fe phthalocyanine (FePc), which has a 16-membered ring ligand, using in situ X-ray absorption spectroscopy; demetalation of the Fe complexes was directly observed during electrochemical experiments performed under acidic ORR conditions.

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Naturally occurring polysaccharides, such as cellulose, hemicellulose, and chitin, have roles in plant skeletons and/or related properties in living organisms. Their hierarchically regulated production systems show potential for designing nanocomposite fabrication using engineered microorganisms. This study has demonstrated that genetically engineered () individual cells can fabricate naturally composited nanofibrils by simultaneous production of hyaluronan (HA) and bacterial cellulose (BC).

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Article Synopsis
  • Scientists studied how liquids flow through special tiny tubes called carbon nanotubes (CNTs) using computer simulations.
  • They looked at a type of gas called argon to learn about how the liquid moves and interacts with the walls of the tubes.
  • They discovered that as the tubes get wider, the way liquids flow changes in steps, with the flow getting faster up to a point, then slowing down again as the tube's structure changes.
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