The diffusion of 63Ni and 114mIn in the intermetallic L12 phase Ni3Al is measured in the temperature range from 900 to 1200 °C and for compositions between 73.5 and 77 at% Ni in steps of 0.5 at%. The In isotope serves as a substitute for 26Al. The usual serial sectioning method is applied using a precision parallel grinder. There is only a weak concentration dependence of the diffusion coefficient at temperatures > 950 °C but it gets stronger with decreasing temperature. There is a minimum of the diffusion coefficient at 76 and not at 75 at% Ni as may be expected. The diffusion of 63Ni in Ni3Al and in pure Ni is comparable. The same is true for the diffusion of 114mIn in Ni3Al. Very likely the diffusion of 63Ni is by a normal vacancy mechanism and the diffusion of 114mIn by In antisite atoms in the Ni sublattice. The D 0*‐values are for In (and probably for Al as well) considerably higher than for Ni. This could be due to a higher entropy term. As a consequence of the considerably larger D 0*‐values of In an intersection of the two linear Arrhenius plots for Ni and Al is observed at about 950 °C for all concentrations except Ni76Al24. This fits well to interdiffusion investigations where at higher temperatures Al is found to be the faster component, and Ni at lower temperatures.

To reveal the structure and release properties of bentonite-alginate nanocomposites, bentonite of different amounts was incorporated into alginate by the sol–gel route. The structure of the composites was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis and related to the swelling property of the matrix and the release of imidacloprid. Bentonite was subject to exfoliation into nanoplatelets and combined into the polymeric network within alginate hydrogel, exhibiting profound effects on the structure features and release properties of the composites. Bentonite was of good compatibility with alginate due to the hydrogen bonding and the electrostatic attraction between them. The polymer chains were found to intercalate into the interlayer gallery of the clay. The high specific area of the nanoplatelets of bentonite benefited the intimate contact with alginate and reduced the permeability of the composites. However, in the composites with clay content of more than 10%, the polymer was insufficient to accommodate the silicate sheets completely. The aggregation of the platelets destroyed the structure integrity of the composites, facilitating the diffusion of the pesticide. The release of imidacloprid was greatly retarded by incorporating into bentonite-alginate composites and dominated by Fickian diffusion depending on the permeability of the matrix. The time taken for 50% of the active ingredient to be released, T 50, first increased and then decreased with increasing clay content in the composites, reaching a maximum around a weight percentage of 10%, at which the T 50 value for imidacloprid release was about 2.5 times that for the release from pure alginate formulation.

The new N-heterocyclic σ-silyl pincer ligand HSiMe­(NCH2PPh2)2C6H4 (1) was designed. A series of tridentate silyl pincer Fe and Co complexes were prepared. Most of them were formed by chelate-assisted Si–H activation. The typical iron hydrido complex FeH­(PMe3)2(SiMe­(NCH2PPh2)2C6H4) (2) was obtained by Si–H activation of compound 1 with Fe­(PMe3)4. The combination of compound 1 with CoMe­(PMe3)4 afforded the Co­(I) complex Co­(PMe3)2(SiMe­(NCH2PPh2)2C6H4) (3). The Co­(III) complex CoHCl­(PMe3)­(SiMe­(NCH2PPh2)2C6H4) (5) was generated by the reaction of complex 1 with CoCl­(PMe3)3 or the combination of complex 3 with HCl. However, when complex 3 was treated with MeI, the Co­(II) complex CoI­(PMe3)­(SiMe­(NCH2PPh2)2C6H4) (4), rather than the Co­(III) complex, was isolated. The catalytic performance of complex 5 for Kumada coupling reactions was explored. With a catalyst loading of 5 mol %, complex 5 displayed efficient catalytic activity for Kumada cross-coupling reactions of aryl chlorides and aryl bromides with Grignard reagents. This catalytic reaction mechanism is proposed and partially experimentally verified.

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