Study of Crystal-field Effects in Rare-earth (RE) - Transition-metal Intermetallic Compounds and in RE-based Laser Crystals

Rare-earth (RE) based compounds and alloys are of great interest both for their fundamental physical properties and for applications. In order to tailor the required compounds for a specific task, one must be able to predict the energy level structure and transition intensities for any magnetic ion in any crystalline environment. The crystal-field (CF) analysis is one of the most powerful theoretical methods to deal with the physics of magnetic ions. In the present work, this technique is used to analyze peculiar physical properties of some materials employed in the production of new-generation solid-state laser and high-performance permanent magnets.Comment: 6 pages, 2 figures; extended abstract of PhD thesis (final version with updated references

Smart Society and Artificial Intelligence: Big Data Scheduling and the Global Standard Method Applied to Smart Maintenance

Abstract The implementation of artificial intelligence (AI) in a smart society, in which the analysis of human habits is mandatory, requires automated data scheduling and analysis using smart applications, a smart infrastructure, smart systems, and a smart network. In this context, which is characterized by a large gap between training and operative processes, a dedicated method is required to manage and extract the massive amount of data and the related information mining. The method presented in this work aims to reduce this gap with near-zero-failure advanced diagnostics (AD) for smart management, which is exploitable in any context of Society 5.0, thus reducing the risk factors at all management levels and ensuring quality and sustainability. We have also developed innovative applications for a human-centered management system to support scheduling in the maintenance of operative processes, for reducing training costs, for improving production yield, and for creating a human–machine cyberspace for smart infrastructure design. The results obtained in 12 international companies demonstrate a possible global standardization of operative processes, leading to the design of a near-zero-failure intelligent system that is able to learn and upgrade itself. Our new method provides guidance for selecting the new generation of intelligent manufacturing and smart systems in order to optimize human–machine interactions, with the related smart maintenance and education

First-principles theory of multipolar order in actinide dioxides

AbstractMagnetic phase transitions that involve multipolar degrees of freedom have been widely studied during the last couple of decades, challenging the common approximation which assumes that the physical properties of a magnetic material could be effectively described by purely dipolar degrees of freedom. Due to the complexity of the problem and to the large number of competing interactions involved, the simple (fcc) crystal structure of the actinide dioxides made them the ideal playground system for such theoretical and experimental studies. In the present paper, we summarize our recent attempts to provide an ab initio description of the ordered phases of UO2, NpO2, and AmO2 by means of state-of-the-art LDA+U first-principles calculations. This systematic analysis of the electronic structures is here naturally connected to the local crystalline fields of the 5f states in the actinide dioxide series. Related to these we find that the mechanisms which lead to the experimentally observed insulating ground states work in distinctly different ways for each compound

Probing magnetism in the vortex phase of PuCoGa5 by X-ray magnetic circular dichroism

We have measured X-ray magnetic circular dichroism (XMCD) spectra at the Pu M4;5 absorption edges from a newly-prepared high-quality single crystal of the heavy fermion superconductor 242PuCoGa5, exhibiting a critical temperature Tc = 18.7 K. The experiment probes the vortex phase below Tc and shows that an external magnetic field induces a Pu 5f magnetic moment at 2 K equal to the temperature-independent moment measured in the normal phase up to 300 K by a SQUID device. This observation is in agreement with theoretical models claiming that the Pu atoms in PuCoGa5 have a nonmagnetic singlet ground state resulting from the hybridization of the conduction electrons with the intermediate-valence 5f electronic shell. Unexpectedly, XMCD spectra show that the orbital component of the 5f magnetic moment increases significantly between 30 and 2 K; the antiparallel spin component increases as well, leaving the total moment practically constant. We suggest that this indicates a low-temperature breakdown of the complete Kondo-like screening of the local 5f moment.JRC.G.I.5-Advanced Nuclear Knowledg

High spin cycles: topping the spin record for a single molecule verging on quantum criticality

The cyclisation of a short chain into a ring provides fascinating scenarios in terms of transforming a finite array of spins into a quasiinfinite structure. If frustration is present, theory predicts interesting quantum critical points, where the ground state and thus lowtemperature properties of a material change drastically upon even a small variation of appropriate external parameters. This can be visualised as achieving a very high and pointed summit where the way down has an infinity of possibilities, which by any parameter change will be rapidly chosen, in order to reach the final ground state. Here we report a mixed 3d/4f cyclic coordination cluster that turns out to be very near or even at such a quantum critical point. It has a ground state spin of S = 60, the largest ever observed for a molecule (120 times that of a single electron). [Fe10Gd10(Me-tea)10(Me-teaH)10(NO3)10]\ub720MeCN forms a nano-torus with alternating gadolinium and iron ions with a nearest neighbour Fe\u2013Gd coupling and a frustrating next-nearest neighbour Fe\u2013Fe coupling. Such a spin arrangement corresponds to a cyclic delta or saw-tooth chain, which can exhibit unusual frustration effects. In the present case, the quantum critical point bears a \u2018flatland\u2019 of tens of thousands of energetically degenerate states between which transitions are possible at no energy costs with profound caloric consequences. Entropy-wise the energy flatland translates into the pointed summit overlooking the entropy landscape. Going downhill several target states can be reached depending on the applied physical procedure which offers new prospects for addressability

Chemometric Differentiation of Sole and Plaice Fish Fillets Using Three Near-Infrared Instruments

Fish species substitution is one of the most common forms of fraud all over the world, as fish identification can be very challenging for both consumers and experienced inspectors in the case of fish sold as fillets. The difficulties in distinguishing among different species may generate a “grey area” in which mislabelling can occur. Thus, the development of fast and reliable tools able to detect such frauds in the field is of crucial importance. In this study, we focused on the distinction between two flatfish species largely available on the market, namely the Guinean sole (Synaptura cadenati) and European plaice (Pleuronectes platessa), which are very similar looking. Fifty fillets of each species were analysed using three near-infrared (NIR) instruments: the handheld SCiO (Consumer Physics), the portable MicroNIR (VIAVI), and the benchtop MPA (Bruker). PLS-DA classification models were built using the spectral datasets, and all three instruments provided very good results, showing high accuracy: 94.1% for the SCiO and MicroNIR portable instruments, and 90.1% for the MPA benchtop spectrometer. The good classification results of the approach combining NIR spectroscopy, and simple chemometric classification methods suggest great applicability directly in the context of real-world marketplaces, as well as in official control plans

Nível de complexidade assistencial e dimensionamento de enfermagem no Pronto-Socorro de um hospital público

Aim: to assess the level of care complexity and the dimensioning of the nursing staff attending in the emergency unit of a public hospital. Method: descriptive and documental study, performed with data extracted from patients’ records. Results: we assessed 998 records. There was a prevalence (73,3%) of patients requiring minimal care. Concerning the nursing staff, the situation according to work shifts corresponded to 32,6% for nurses and 91,5% for nursing auxiliary/technicians from the frame projected for the unit. Conclusions: the prevalence of patients needing minimal care may stem from an inadequate flow of care provided for the health services and, consequently, producing an unnecessary use of the tertiary health services and, so, increasing the number of attendances. This context is worsened by the reduced number of nursing workers available to provide a qualified and safe careObjetivo: investigar la complejidad asistencial y la dimensión del profesional de enfermería en el sector de urgencias de un hospital público. Método: estudio descriptivo y documental realizado con datos de registros de los pacientes. Resultados: fueron evaluados 998 registros, en que hubo el predominio (73,3%) de pacientes clasificados en cuidados mínimos. En relación a los profesionales de enfermería, el cuadro existente por turno de trabajo correspondió a 32,6% para la categoría de enfermero y 91,5% para auxiliares/técnicos de enfermería del cuadro de profesionales proyectado para la unidad. Conclusiones: el predominio de pacientes clasificados como cuidados mínimos presupone la inadecuación del flujo de atención de los servicios de salud y consecuente uso equivocado de la atención terciaria, generando número expresivo de atendimientos. Este contexto se agrava por la reducida cantidad de profesionales de enfermería para prestar asistencia con calidad y seguridad.http://dx.doi.org/10.5902/2179769216811Objetivo: analisar o nível de complexidade assistencial e o dimensionamento dos profissionais de enfermagem no pronto-socorro de um hospital público. Método: estudo transversal descritivo realizado com dados extraídos de prontuários de pacientes. Resultados: foram avaliados 998 prontuários, destes houve predomínio (73,3%) de pacientes classificados em cuidados mínimos. Em relação aos profissionais de enfermagem, o quadro existente por turno de trabalho correspondeu a 32,6% para a categoria enfermeiro e 91,5% para auxiliares/técnicos de enfermagem do quadro de pessoal projetado para a unidade. Conclusões: o predomínio de pacientes classificados como em cuidados mínimos pressupõe a inadequação do fluxo de atenção dos serviços de saúde, e consequente utilização equivocada da atenção terciária, gerando número expressivo de atendimentos. Este contexto é agravado pelo quantitativo reduzido de profissionais de enfermagem para prestar assistência com qualidade e segurança