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Artigo IPEN-doc 28524 Magnetic and structural properties of the intermetallic Ce(1−x)LaxCrGe3 series of compounds2021 - BOSCH-SANTOS, B.; CABRERA-PASCA, G.A.; CORREA, E.L.; CORREA, B.S.; SALES, T.N.S.; MOON, K-W.; DENNIS, C.L.; HUANG, Q.; LEAO, J.B.; LYNN, J.W.; CARBONARI, A.W.The Ce(1−x)LaxCrGe3 (x = 0, 0.19, 0.43, 0.58, and 1) intermetallic compound system has been investigated by magnetization measurements and neutron scattering techniques to determine the effect of La doping on the magnetic ordering and exchange interaction between Cr ions. The structural and magnetic characterization in this series was first verified by x-ray diffraction and bulk magnetization measurements. The samples exhibit the known hexagonal perovskite structure (P63/mmc space group) and have a single magnetic phase according to magnetizationmeasurements. In this paper, the ferromagnetic ordering temperature for Cr evolves smoothly from a range of 68 K to 77 K for CeCrGe3 to a range of 91 K to 96 K for LaCrGe3 as La replaces Ce. Magnetization results indicate the formation of domain walls below the transition temperature for all Ce(1−x)LaxCrGe3 systems investigated. Neutron results indicate ordered magnetic Cr moments aligned along the c axis for the x = 1 LaCrGe3 system, as well as for x = 0.19, 0.43, and 0.58, which contrasts with the x = 0 CeCrGe3 where the moments order in the ab plane.Artigo IPEN-doc 25107 Influence of the vials radioactive residue in Nuclear Medicine procedure applied to a new “in situ” activimeter calibration methodology2019 - KUAHARA, L.T.; CORREA, E.L.; CARNEIRO, R.C.G.; BEZERRA, R.R.L.; POTIENS, M.P.A.In this study we present a new “in situ” calibration methodology establishment for activimeters – i.e., this equipment calibration can be made at the hospital and/or the nuclear medicine service (NMS) – and also the importance of considering vials radioactive residue when generating the calibration coefficient in terms of activity (NA). For the calibration, two methods are presented here: in the first, 99mTc sample activity (AC) is measured in the NMS. Then it is sent to the Instruments Calibration Laboratory (LCI/IPEN) where the reference activity (AR) is obtained under controlled conditions in a reference vial. After geometry and residue corrections, NA is calculated. In the second method, AR is obtained at the LCI, then 99mTc sample is sent to the hospital/NMS, where AC is measured and NA calculated. Calibration methodologies were applied to three NMS and to four equipment belonging to the radiopharmaceutical production facility (CR) at the Nuclear and Energy Research Institute (IPEN). Both methodologies were tested with and without residual activity corrections under controlled conditions. Variations of up to 4% were obtained.