Novel Rh complexes, Rh[C(C 6H5)dC(C6H5)2](nbd)(4-XC6H4)3P (1a: X ) F; 1b: X ) Cl), were isolated from mixtures of [(nbd)RhCl]2, (C6H5)2CdC(C6H5)Li, and (4-XC6H4)3P, and the polymerization of phenylacetylene thereby was investigated. The polymerization by 1a in toluene at 30 °C in the presence of (4-FC6H4)3P (5 equiv to Rh or more) proceeded with virtually quantitative initiation efficiency to give polymer with low polydispersity (Mw/Mn ∼1.05). The living character of this polymerization was confirmed by means of both the time profile of polymerization and the multistage polymerization. Toluene, benzene, and THF were particularly useful as polymerization solvents; the polydispersity remained 1.05-1.06, while the larger the dielectric constant of the solvent, the slower the polymerization. This polymerization smoothly proceeded in the temperature range 15-60 °C.

Ihe removdl of c d k iu h as Pb2+ Mn2+, Co2+ and Cu2+ in aqueous solution by four synthetic hydroxyapatites (S-1, S-2, S-3, S-4) has been investigated using both batch and column methods. The removal is due not only to an adsorption effect but also to an ion-exchange reaction between the cations in solution and the Ca2+ ions of the apatites. The order of the ions according to the amount exchanged was as follows: Pb2+ > Cu2+ > Mn2+ 1 : Co2+. Pb2+ ions were readily removed by the apatites and the maximum value for the exchange of Pb2+ ions was 230 mg per g of S-4 apatite. The apatites, particularly S-4, would seem to be possible agents for the removal of toxic Pb2+ ions. The selectivity of the apatites for the cations can be explained by considering the radii and the electronegativities of the ions.

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The ion-exchange characteristics between Pb2+ ions of aqueous solutions containing various counter-anions (F-, C1-and NO;) and Ca2+ ions of synthetic hydroxyapatite samples have been investigated in detail under the conditions of low pH values (3.0, 4.0 and 5.0).The ratio of removal of Pb2+ ions to the apatites increased with a decrease in pH from 5.0 to 3.0, but even at pH 5.0 the ratio of removal of Pb2+ ions increased from 10 to 60% as the reaction time increased from 2 h to 20 days.Even at the low pH value of 3.0 the apatite structure in a solution contaning For C1-ions was maintained via a concurrent ion-exchange effect of Pb2+ ions together with For C1-ions, which are known to be exchangeable for OH-ions of the apatite, while the apatite structure in the system containing NO; ions was destroyed by protons. This destruction is thought to be due to the fact that since NO; ions cannot be exchanged for OH-ions, the retention of the apatite structure together with Pb2+ ions was made impossible by the loosening or dissolving effect of protons on the skeletal structure of the apatite at such a low pH as 3.0. Moreover, the crystal structure of Pb2+ ion-exchanged apatite [Ca,~,Pb,.,(P0,),(OH)2], with a = 9.882(3) 8, and c = 7.417(2) A. has been investigated by the X-ray powder pattern-fitting method. The determined site occupancy factors of Pb2+ ions were almost the same, i.e. 0.75 and 0.57 for M1 and M2 (column site) sites, respectively.These results show that Ca2+ ions in the apatite sample can easily be exchanged for Pb2+ ions almost without distinction between M1 and M2 sites, assisted by the loosening effect of protons even at room temperature. The hydroxyapatite can easily be converted into stable lead apatite in acidic solutions containing exchangeable anions such as For C1-by a synergistic efiect.

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The photoinduced wettabilities of water, n-hexadecane, dodecane, and n-heptane on a flat TiO2 surface prepared by a sol-gel method-based coating were investigated. An amphiphilic surface produced by UV irradiation exhibited underwater superoleophobicity with an extremely high static oil contact angle (CA) of over 160°. The TiO2 surface almost completely repelled the oil droplet in water. A robust TiO2 surface with no fragile nanomicrostructure was fabricated on a Ti mesh with a pore size of approximately 150 μm. The fabricated mesh was found to be applicable as an oil/water separation filter.

The structure of SiOz-Alz03 glasses with up to 60 wt % AIzO3 was investigated using the radial distribution function together with the correlation method based on X-ray scattering intensity data. Radial distribution curves are interpreted on the basis of glass-in-glass separation with the constituents of SiOz-rich and AIzO3-rich glasses. The structure of the AlzOa-rich glass has a short-range ordering similar to the crystal structure of mullite. The calculated S i ( S ) curve of this model gives good agreement with the observed one.

The Ruddlesden–Popper phases, Lan+1NinO3n+1 (n=1, 2, and 3), were synthesized by a solid‐state reaction for use as cathodes in an intermediate‐temperature (500°–700°C) solid oxide fuel cell. The samples crystallized into an orthorhombic layered perovskite structure. The overall electrical conductivity increased with the increase of n in the intermediate temperature range. Single test‐cells, which consisted of samarium‐oxide‐doped ceria (SDC; Sm0.2Ce0.8Ox) as an electrolyte, Ni–SDC cermet (Ni–SDC) as an anode, and Lan+1NinO3n+1 as a cathode, were fabricated for measurements of cell performance at 500°–700°C. Current interruption measurements revealed that both the ohmic and overpotential losses at 700°C decreased with the increase of n. La4Ni3O10 was found to exhibit the best cathode characteristics in the Lan+1NinO3n+1 series. Maximum test‐cell power densities with La4Ni3O10 (n=3) were 10.2, 36.5, and 88.2 mW/cm2 at 500°, 600°, and 700°C, respectively.