Using a sol-gel method we have prepared monodispersive particles of La0.67Ca0.33MnO3 in the range from 20 to 110 nm at temperatures from 540 to 1000 °C. A magnetoresistance above 10% was obtained in a field of 1 kOe for all the particles sizes. These results may be relevant for future applications.

We report evidence of the formation of small atomic copper clusters, Cu(n), by the microemulsion technique, and how their size can be controlled by adjusting the percentage of the reducing agent used. Copper clusters were characterized by UV-visible spectrophotometry and atomic force microscopy. Photoluminescent copper clusters, Cu(n), with n less, similar 13, can be obtained using very low percentages of the reducing agent (<10% of the stochiometric amount). Photoluminescent clusters disappear for larger percentages of reducing agent, giving rise to larger copper clusters (0.8-2.0 nm), showing a red-shift of their UV-visible absorption bands as they grow in size. Finally, by using near stoichiometric amounts, nanoparticles of 2.9 +/- 1.1 nm in size, displaying the characteristic plasmon band, can be obtained.

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A series of polyacrylonitrile‐block‐polystyrene (PAN‐b‐PS) and polyacrylonitrile‐block‐poly(methyl methacrylate) (PAN‐b‐PMMA) diblock copolymers with PAN volume fraction up to 20% self‐assembles in nonpolar selective solvents to form cylindrical micelles with a PAN core, having contour length varying between less than 1 µm and tens of micrometers. Micelle characterization by differential light scattering, nuclear magnetic resonance, transmission electron microscopy, atomic force microscopy and differential scanning calorimetry enabled to point out the role played by crystallinity during micellization, thence suggesting that the core crystallization force overcomes other factors governing self‐assembling processes.

Two of the main types of nanotubular architectures are the single-walled carbon nanotubes (SWCNTs) and the self-assembling cyclic peptide nanotubes (SCPNs). We here report the preparation of the dual composite resulting from the ordered combination of both tubular motifs. In the resulting architecture, the SWCNTs can act as templates for the assembly of SCPNs that engage the carbon nanotubes noncovalently via pyrene "paddles", each member of the resulting hybrid stabilizing the other in aqueous solution. The particular hybrids obtained in the present study formed highly ordered oriented arrays and display complementary properties such as electrical conductivity. Furthermore, a self-sorting of the cyclic peptides toward semiconducting rather than metallic SWCNTs is also observed in the aqueous dispersions. It is envisaged that a broad range of exploitable properties may be achieved and/or controlled by varying the cyclic peptide components of similar SWCNT/SCPN hybrids.

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