Abstract. The XAFS2 is a general-purpose X-ray absorption beamline. It is the second one built at the LNLS. After approximately 7 years in operation this beamline has been substantially updated in order to improve its experimental possibilities. Recently arrived, a 4-circle Huber diffractometer has been incorporated to perform combined experiments. This collects XRD patterns with the XAFS. Through the development of a new sampling environment it is now also possible to perform these measurements in situ/operando conditions. Other upgrades include a complete remodelling of the beamline software and its control system. The following new systems are crucial for the next steps that are currently underway at the beamline, namely, (i) enabling remote access for users and (ii) the testing of QEXAFS measurements. IntroductionUpon the completion, in 2007, of the commissioned works on the XAFS2 [1], a large number of users have been using this experimental facility in order to perform several kinds of experiments [2][3][4][5]. Since 2007, and with the development of combined simultaneous characterizations [6], there are a plethora of new possibilities additional to the usual XAFS experiments. Among these numerous possibilities; a combined XAFS and XRD experiment would be especially useful in order to obtain structural information of the short range order (around a selected absorber atom) and of the long range order, thus unveiling information on the material as a whole. Here one is probing different properties of the same system in a unique experiment under the same conditions, thus bridging the complex gaps in the structure. Therefore, in order to improve those abilities of the beamline, a 4-circle Huber Diffractometer was added to the experimental hutch in order to explore both techniques [7] through user demand. Here below an example of these XAFS and XRD measurements is presented. The example shows the performance of the beamline at work while combining both techniques.Importantly, the control system of the beamline has been renovated by the installation of a PXI. The PXI is from National Instruments (PXI-NI) and communicates with Galil/Parker controllers on an EPICS platform [8]. Note some parts of the motors were changed in order to improve performance with the upgrade and there were also important changes to the control hardware. The Windows

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In this work, FeCo nanoparticles were synthesized in Core-Shell conformation by synthesis called Sol-Gel-Proteic route. This method is derived from the conventional sol-gel, and used as edible gelatin precursor organic. First was prepared a solution containing nitrates of iron and cobalt and gelatin edible, which was under constant agitation so that the mixture became uniformly dispersed, prior to remain in the oven for 48 hours at a temperature of 100 °C. Then, the obtained xerogel was macerate and kept in a rotary kiln for 2 hours at 700 °C with an air flow of 40 mL/min to promote oxidation of the sample. From the oxidation process, the work was divided into two parts. In the first part tried to obtain samples in which the core consisted of the FeCo alloy, while the shell was composed by Fe 3 O 4 . In the second we tried to obtain the opposite structure, with the core formed by the oxide and the shell formed by the alloy. Some conditions were varied during synthesis so as to try to control size of the core and shell, oxidation temperature and observe changes in the magnetization saturation. The samples were characterized by X-ray diffraction, transmission electron microscopy, Thermogravimetry, Vibrant Sample Magnetometry and Mössbauer Spectroscopy, and the results obtained compared with literature studies.