title: Scattering from dilute ferrofluid suspensions in soft polymer gels.
abstract: Small angle neutron and x-ray scattering methods are used to investigate the structure of dilute suspensions of two different ferrofluid systems dispersed in soft polyacrylamide hydrogels. It is found that the particles in the fluid are fractal aggregates composed of smaller particles of radius ca. 5 nm. The fractal dimension is strongly dependent on sample, taking the value 1.7 in the first sample and 2.9 in the second sample. In the presence of a magnetic field the aggregates orient, but are restricted in both their translational and rotational freedom. The effect of the gel elasticity is treated as a hindrance to the orientation process.
authors.affiliation: Laboratoire de Spectrométrie Physique UMR CNRS 5588, Université Joseph Fourier de Grenoble, Boîte Postale 87, 38402 St. Martin d'Hères, France. alvarot@fisica.ufmg.br
authors.forename: Alvaro V
authors.initials: AV
authors.lastname: Teixeira
authors.forename: Isabelle
authors.initials: I
authors.lastname: Morfin
authors.forename: Françoise
authors.initials: F
authors.lastname: Ehrburger-Dolle
authors.forename: Cyrille
authors.initials: C
authors.lastname: Rochas
authors.forename: Erik
authors.initials: E
authors.lastname: Geissler
authors.forename: Pedro
authors.initials: P
authors.lastname: Licinio
authors.forename: Pierre
authors.initials: P
authors.lastname: Panine