Due to their high aspect ratio, magnetic nanowires are interesting for various applications. Fe nanowires are of particular interest due to their high magnetization, which suggests high shape anisotropy is possible. Here, we show how the electrodeposition process can be adapted to the constraints of a high aspect ratio template in order to approach an ideal behaviour of smooth and pure Fe nanowires. An adjustment of the Fe 2+ concentration and the addition of H 3 BO 3 result in smooth and continuous nanowires; saturation polarization is achieved, together with an anisotropy field of up to 70% compared to pure Fe. Mossbauer spectroscopy reveals a negligible amount of impurities. Together with magnetic measurements we show that shape anisotropy aligns the preferential magnetization axis along the wire axis.
Using magnetic measurements structural irregularities in electrodeposited nanotubes are inferred. The correlation between morphology and magnetic properties is very useful for studying materials. Through the use of the magnetic switching field distribution, the association with the surface irregularities imperfections of the magnetic nanotubes was performed. The distribution of magnetic switching field presents well behaved in smooth-surface nanotubes and, for nanotubes with irregularities, the distribution of switching fields has a noisy behavior, added to that smoothed signal. This noise is due to the superficial irregularities on the tubes surface because the magnetic barriers occurring in imperfect structures. Pinning centers due to irregularities are the principal aspect to observe in this situation. Magnetic measurements were associated directly to the morphology obtained by scanning electron microscopy.
We present the case of a 50-year-old man who developed a delayed progressive swelling over the medial aspect of his right thigh, six weeks following minimally invasive plate osteosynthesis (MIPO) of a supracondylar femur fracture. Angiography showed a false aneurysm of the superficial femoral artery, caused by progressive displacement of a butterfly fragment. Open vascular repair was performed and the sharp edge of the butterfly fragment was removed.