Tunable optical emission properties from ferromagnetic semiconductors have not been well identified yet. In this work, high-quality Mn(II)-doped CdS nanowires and micrometer belts were prepared using a controlled chemical vapor deposition technique. The Mn doping could be controlled with time, precursor concentration and temperature. These wires or belts can produce both tunable redshifted emissions and ferromagnetic responses simultaneously upon doping. The strong emission bands at 572, 651, 693, 712, 745, 768, 787 and 803 nm, due to the Mn(II) (4)T1((4)G)  → (6)A1((6)s) d-d transition, can be detected and accounted for by the aggregation of Mn ions at Cd sites in the CdS lattice at high temperature. These aggregates with ferromagnetism and shifted luminescence are related to the excitonic magnetic polaron (EMP) and localized EMP formations; this is verified by ab initio calculations. The correlation between aggregation-dependent optical emissions and ferromagnetic responses not only presents a new size effect for diluted magnetic semiconductors (DMSs), but also supplies a possible way to study or modulate the ferromagnetic properties of a DMS and to fabricate spin-related photonic devices in the future.

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The absorption of water in glass fiber reinforced epoxy resins is a complex process. With dynamic-mechanical measurements it is possible to distinguish locations of water in the resin-glass interphase, in micro-cracks of the resin, and diluted in the bulk polymer. The dominant mechanism of incorporation depends on the resin/hardener system, the surface treatment of the glass fabrics, and the sorption temperature.

Water sorption was determined and dynamic‐mechanical measurements made on dry and water‐containing systems. Different types of surface treatments of the glass fiber were studied. Immobilization of polymer chains in the interphase is determined by the nature of the curing system, annealing conditions, and surface treatment of glass fibers. Penetrating water can be found at three kinds of locations in the composite; water in the interphase has different properties than water in the polymer matrix and in microvoids. This fact can be used as a microscopic probe in epoxy‐containing composites. Water content depends on the density of polar groups and the density of the network. At higher temperatures water causes crazes, at lower it mainly acts as a plasticizer. Water in crazes does not affect the glass transition temperature Tg, but it decreases (tan δ) and weakens the material. As long as water mainly goes into swelling, energy transfer between the resin and the matrix is not affected. The reinforcement then works as it should. The results demonstrate the importance of interphase properties on the behavior of the composite.

Dynamic-mechanical measurements were used to study the properties of the interphase in glass fibre reinforced epoxy resins. The immobilisation of the polymer chains in the interphase is determined by the curing system, the annealing process, and the surface treatment of the glass fibres.