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SmCo films with a Cr underlayer have been investigated as potentially attractive candidates for high density recording media. Magnetron sputtering was used here to produce Cr/SmCo x /Cr films on Si ͑100͒ substrates. The magnetic films were deposited at a substrate temperature of 350°C and an Ar pressure of 5 mTorr. Cr underlayers were deposited both at 25°C and at 350°C and exhibited different textures. Layer thicknesses were evaluated using Rutherford backscattering spectroscopy, while SmCo grain size and underlayer texture were determined from a Rietveld analysis of x-ray diffraction data. The magnetic properties were measured with a vibrating sample magnetometer. The resulting films had in-plane coercivities in the range 4-8 kOe. For a SmCo layer with a thickness of 200 nm, the Cr underlayer thickness was varied in the range 75-300 nm to study its effect on intergranular coupling in the films. For thermally demagnetized samples, both magnetizing and demagnetizing remanence curves were measured and used to evaluate switching field distributions and ␦m plots. The underlayer texture was found to affect magnetic properties more strongly than underlayer thickness.

Systematic research into art and cultural heritage objects in museum collections are growing daily across the world. They are generally undertaken in partnership with archaeologists, curators, historians, conservators, and restorers. The use of scientific methods to answer specific questions about objects produced by different societies reveals the materials and technologies used in the past and gives us a better understanding of the history of migration processes, cultural characteristics, and thereby more grounded parameters for the preservation and conservation of cultural heritage. The use of non-destructive methods, such as the PIXE analysis, is very suitable in such studies because damage or alteration is avoided and the integrity of the object maintained. Such techniques gave historians and curators at the Archaeological and Ethnology Museum in São Paulo new understanding of the Chimu collection of ceramics as well as of the technical process of preventive conservation.

Nuclear energy represents 13% of the present worldwide electric power consumption, but in Brazil only about 2.4% of the energy matrix is due to the nucleo-electric power. As the Brazilian hydroelectric capabilities have been threatened by the water supply shortage by environmental conditions, nuclear technology need to overcome specific challenges aiming at supporting the nuclear reactors development in a sustainable, reliable and efficient perspective. This work addresses the recent theoretical and experimental activities carried out at IFUSP, FATECSP+CEETEPS and POLI-USP in the field of materials sciences and the current challenges of using ion beams to emulate neutron damage in cladding materials candidates with enhanced properties towards accident conditions. Additionally, a new vacuum system is introduced coupled to the LIO-LAMFI (LAMFI is an acronymous to the portuguese expression "Laboratório de Materiais e Feixes Iônicos".) implanter allowing to extend the capability of the system to perform implantation at temperatures higher than room temperature.