Reactions of quinquedentate Schiff base ligands with Mn and Cu ions afforded icosa- and hexadecanuclear mixed-metal clusters in which dinuclear CuII complexes trapped oxo-bridged [MnIII8MnIV4O12] and [MnIII6O6] cores, respectively. Maximum entropy method analysis for synchrotron X-ray diffraction data was used to determine the oxidation states of the Mn ions.

MCM-41 (#41 Mobil Composition of Matter) is a favorable material for heterogeneous reactions because of its unique porous structure. However, the catalytic activity of MCM-41 for the oxidative dehydrogenation (ODH) of isobutane to isobutene is known to be quite low. In the present study, a metal-doping method was employed to improve this catalytic activity. Doping of Cr, Co, Ni, or Mo into MCM-41 resulted in a great improvement in the catalytic activity. Since chromium-doped MCM-41 (Cr-MCM-41) showed the greatest catalytic activity among these catalysts, its redox property was further analyzed via XPS, XAFS and H 2-TPR techniques. The XPS spectrum of Cr-MCM-41 suggested that it has Cr 3+ and Cr 6+ species on its surface. Also, a pre-edge peak due to Cr 6+ species was confirmed in the XANES spectrum of Cr-MCM-41. In H 2-TPR measurement, Cr-MCM-41 was more reducible than crystalline Cr 2 O 3 , which showed low catalytic activity for the ODH of isobutane. The reducible Cr 6+ species on Cr-MCM-41 contributed to an improvement in the catalytic activity of MCM-41.

The study on the synthesis of π‐conjugated polymers using cobaltacyclopentadiene formation reaction of CpCo(PPh3)2 and conjugated diacetylene and the structure and physical properties of the polymers is overviewed. The substituents on the diacetylene affect crucially the solubility, the degree of polymerization, redox properties, and electronic structures and so on. Recent synthesis of a ruthenacyclopentatriene polymers by metallacyling polymerization is also described.

A ruthenacyclopentatriene polymer 2 was synthesized by metallacycling polymerization (MCP). Polymer 2 with Mn = 3400 and Mw = 5800 consisted of identical ruthenacyclopentatriene units. The UV-vis spectra of 2 showed a shift of the pi-pi* band to a longer wavelength due to the enlargement of the pi-conjugation. Polymer 2 underwent reversible reduction due to the ruthenacycle moiety at -1.01 V versus ferrocenium/ferrocene. The EPR spectrum of the reduced form of 2 in frozen THF indicated ferromagnetic interaction of spins at ruthenacyclopentatriene units.

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The template ion exchange of chromium cations into FSM-16 (#16 Folded Sheets Mesoporous Materials) for 247 h resulted in a 2.89 wt % incorporation of those cations into the FSM-16, although only a 0.3 wt % incorporation had previously been reported. The XRD pattern of the resultant solid (Cr-FSM-16) showed that the hexagonal structure characteristic of FSM-16 remained after the 2.89 wt % incorporation of chromium cations. XPS could be used to detect the Cr 3+ and Cr 6+ species on the surface of Cr-FSM-16. A pre-edge peak that was due to a tetrahedrally coordinated Cr 6+ species was confirmed in the XANES spectrum of the Cr-FSM-16, which showed that the coordination state around some Cr species was similar to that around the Si species in FSM-16. With the increase in the amount of chromium cations in FSM-16, its catalytic activity and stability during the oxidative dehydrogenation of isobutane were evidently improved.

Water-soluble nonionic polymers of polyethylene glycol (PEG), poly(vinyl alcohol) (PVA), and polyvinylpyrrolidone (PVP) were examined to develop the dispersion of graphene in an aqueous surfactant solution. Sodium dodecylbenzenesulfonate was used as an anionic surfactant to disperse graphene in an aqueous solution and to give negative charge on it. The dispersion of graphene was monitored through the electropherograms in affinity capillary electrophoresis; a broad peak for the dispersed graphene and shot signals for the aggregated one. When PEG was added in the separation buffer as an affinity reagent, the number of the shot signals in the electropherogram was reduced; PEG can develop the dispersion of graphene in an aqueous surfactant solution. The dispersion was also developed with PVP or PVA. The effective electrophoretic mobility of the dispersed graphene was reduced by using the polymer as an affinity reagent. The result suggested that the anionic surfactant on the graphene surface was competitively substituted with the nonionic polymer. The degree of the decrease in the effective electrophoretic mobility was larger with PEG with a high-molecular mass. The broad peak of the dispersed graphene got narrower by the addition of PEG, and the number of theoretical plates was improved.

Layered double hydroxide (LDH) is a layered hydroxide and exchangeable anion is intercalated in its interlayer. Application of the LDH as a controlled-release material of interlayer anions has become of interest, thus it is important to clarify the elution behavior of interlayer anions. We synthesized hydrogenphosphate-intercalated Mg / Fe and Zn / Fe LDH and elution of phosphate from these LDH were tested in deionized water, sodium chloride solution, sodium sulfate solution, and sodium carbonate solution. For Mg / Fe LDH, the amount of eluted phosphate increased with time and reached to maximum that increased as higher concentrate solution was used. The elution of phosphate from Mg / Fe LDH could be described by the pseudo second-order equation. This elution behavior was explained as ion-exchange reaction of phosphate with sulfate or carbonate in tested solution by means of kinetic simulation using Runge-Kutta method. In the eluted solution, metal ions contained in the LDH were detected and its amount depended on pH of the tested solution, that is, amounts of eluted Mg and Zn ions were small at higher pH (ca. 10) for Mg / Fe and Zn / Fe LDH respectively, but large amount of Zn ion was detected when 2.03 mol·l-1 carbonate solution (pH = 13) was used. Thus elution of phosphate was caused by two main reactions: ion exchange and decomposition of the LDH.