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We present an effective direct extraction method for particle size distribution based on Bayesian inference theory with a free-form model. We give an example of the application to the particle size distribution analysis in ferrofluid consisting of cobalt particles in toluene. The method gives a unique solution to the distribution without assuming the shape of the distribution of the particle size. Index Terms--Bayesian inference, ferrofluid, size distribution.

We report the size effect on the magnetic properties in Prussian blue nanowire arrays. Samples with diameters in the range of 50–200 nm have been prepared by an electrodeposition technology with two-step anodizing anodic aluminum oxide films. The Mössbauer measurement results show that the composition of the continuous and highly crystalline Prussian blue nanowires with a fcc cubic structure remains the same as the diameters of nanowires decreasing with respect of Prussian blue bulk. The magnetic properties of the nanowires were investigated with the magnetic property measurement system. The Curie temperature is found to been reduced with respect to Prussian blue bulk, resulting from the diminution of the average number of nearest magnetic interaction neighbors and magnetic exchange interaction constants as the diameters of nanowires decrease. The low temperature hysteresis loops is also discussed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Short-range magnetic ordering in amorphous Fe-B alloys prepared by borohydride reduction was investigated using zero field spin echo nuclear magnetic resonance analysis. The results showed that the types of short-range order in the samples varied depending on the B concentration. In rapidly-quenched amorphous ribbons, Fe3B-like short range order was observed.

The article discusses a new pulse laser deposition technique, which can be employed for the fabrication of the highly textured manganese zinc ferrite films on glass substrates. The growth of the textured structure is shown to lead to the introduction of stain in these films.

Abstract: CoFe2O4 nanowire arrays were fabricated by electrodeposition of Fe2+ and Co2+ into anodic aluminum oxide (AAO) templates and further oxidization. The phase structure of the nanowires is cubic spinel-type, and the XRD result exhibits perfect preferred crystallite orientation along the nanowire axes. Compared with CoFe2O4 nanowire arrays synthesized by other methods, the magnetic hysteresis loops demonstrate that the arrays of nanowires exhibit uniaxial magnetic anisotropy with easy magnetization direction along the nanowire axes owing to the large shape anisotropy. This approach provides a facile technology to fabricate oxide nanowires with uniaxial magnetic anisotropy. [Copyright &y& Elsevier]

Abstract: Arrays of Fe0.92−x Co x P0.08  ternary alloy nanowires were fabricated in anodic aluminium oxide templates by electrochemical deposition. The broadened peaks in transmission Mössbauer spectra and the halo in selected area electron diffraction patterns indicate that the structure of Fe0.92−x Co x P0.08 nanowires is amorphous. However, the short-range order of Fe0.92−x Co x P0.08 nanowires has a bcc structure with a [110]-preferred orientation that is parallel to the nanowires. The magnetic texture results in the magnetic moment direction of the Fe atoms being along the nanowires. The short-range order around the Fe atoms reaches a minimum at . With increasing Co content, the average hyperfine field decreases, while the isomer shift and quadrupole splitting remain almost constant, which result from the variation of 3d and 4s electron volume density at the Fe sites. [Copyright &y& Elsevier]