Highly active postspinel-structured catalysts for oxygen evolution reaction.

The rational design principle of highly active catalysts for the oxygen evolution reaction (OER) is desired because of its versatility for energy-conversion applications. Postspinel-structured oxides, Ca O ( = Cr, Mn, and Fe), have exhibited higher OER activities than nominally isoelectronic conventional counterparts of perovskite oxides LaO and spinel oxides Zn O. Electrochemical impedance spectroscopy reveals that the higher OER activities for Ca O series are attributed to the lower charge-transfer resistances.

Metamagnetic Behavior in a Quadruple Perovskite Oxide.

A cubic quadruple perovskite oxide CeMnCrO has been synthesized under high-pressure and high-temperature conditions of 8 GPa and 1273 K. The X-ray absorption spectroscopy reveals that the Ce ions are in a trivalent state, as represented by the ionic model of CeMnCrO. The magnetic study demonstrates three independent antiferromagnetic transitions attributed to Ce (∼10 K), Mn (46 K), and Cr (133 K) ions.

New tantalum ligand-free catalyst system for highly selective trimerization of ethylene affording 1-hexene: new evidence of a metallacycle mechanism.

Mild and salt-free reduction of MCl(5) (M = Nb, Ta) has been achieved by using 3,6-bis(trimethylsilyl)-1,4-hexadiene derivatives as reducing reagents. The salt-contact-free low-valent TaCl(3) exhibits high catalytic activity for the trimerization of ethylene to 1-hexene (>1000 TOF) with excellent selectivity (>98%). This salt-free tantalum system enables us to observe new evidence for a metallacycle mechanism.

Histology and immunohistochemistry of fibrous posterior capsule opacification in an infant.

We report the histological findings in posterior capsule opacification (PCO) in 2 eyes of a 10-month-old infant 8 months after cataract extraction and intraocular lens (IOL) implantation. The PCO in the right eye had a regenerated lenticular structure; in the left eye, it was fibrotic. The PCO in the right eye was soft and aspirated with Simcoe's irrigation/aspiration cannula; in the left eye, it was excised surgically.