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Highlights: [•] Statistical Learning methods outperform logistic regression and linear and quadratic discriminant analysis. [•] Credit scoring models based on supervised classification algorithms increase the efficiency of microfinance institutions. [•] With the implementation of a MLP-based model, the MFIś misclassification costs are reduced to 13.7%. [•] A freely available software, the R system, can be used to fit these models. [Copyright &y& Elsevier]

A solid state method was used to synthesize La 1-x Pu x PO 4 (x = 0.01, 0.05, 0.10, 0.15, (0.5)) solid solutions with monazite structure. XRD measurements of the compounds with x = 0.50 revealed the formation of two phases: (La,Pu)PO 4 -monazite and a cubic phase (PuO 2 ). Pure-phase La 1-x Pu x PO 4 -monazite solid solutions were obtained for materials with x = 0.00–0.15 and confirmed by a linear dependence of the lattice parameters on composition according to Vegard's law. X-ray absorption spectroscopy (XAS) analysis at the Pu-L III and La-L III edges confirmed the +III valence state of plutonium in the monazite solid solutions. The local environment of Pu is PuPO 4 -like along the solid solution series, except for the longest fitted cation-cation distance, which may be an indication of cluster formation consisting of a few Pu-atoms in the La-Pu-monazite lattice. [ABSTRACT FROM AUTHOR]

• A shelf life of 3 years can be achieved for large sized dried spikes if cellulose acetate butyrate is used as embedding matrix. • With the addition of plasticizer, the shelf life of these mixed nuclear certified reference materials can be extended to at least 4 years. • It is important to control environmental conditions during production and suppress acid catalysed hydrolysis. • In case the embedding matrix remains intact, the validity of the certificate can be further extended via post certification monitoring, using isotope dilution thermal ionization mass spectrometry. The use of a solvent cast film made of cellulose acetate butyrate (CAB) to embed dried actinides is well known and has been applied for about 20 years. Our goal was to improve the initial mechanical properties of CAB films by delaying crack formation and flaking and thereby extending the shelf life of large sized dried (LSD) spike certified reference materials (CRMs). Two different plasticizers, dioctyl phthalate (DOP) and triethyl citrate (TEC), were tested and their influence on static mechanical properties was studied by comparing stress-strain traces. Their thermal behaviour was analysed by Differential Scanning Calorimetry (DSC). DOP overperformed TEC in terms of elasticity and toughness. Visual observation and Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Spectroscopy (EDS) analysis was performed as a function of time on four different LSD spikes: the IRMM-1027 series of LSD spike CRMs and three in-house prepared non-certified LSD spikes that differed in terms of most abundant isotopes and actinide mass. It was demonstrated that LSD spike CRMs embedded in a CAB matrix with a DOP plasticizer mass fraction of at least 20% have guaranteed 4 years of shelf life, provided that the embedding film is prepared with great care following protocols for preparation. Acid catalysed hydrolysis should be minimized during the production of the CRM because it could alter the advantageous effects of the plasticizer in the matrix. [ABSTRACT FROM AUTHOR]

Aerosols were produced from a MOX (Mixed Oxide of uranium and plutonium) sample by laser heating up to 4000 K under atmospheric conditions. They were collected with a cascade impactor as function of their aerodynamic size, and studied by SEM, EDS, TEM, EELS, SAED and ICPMS. The uranium and plutonium concentrations were related to the aerosol morphology, size and formation temperature. A clear decrease of the Plutonium concentration was observed as function of the Aerodynamic Equivalent Diameter (AED). Some bigger aerosols enriched in Plutonium were found which originated from solidification of ejected droplets of the liquid phase at the surface of the sample. • In sub micrometric aerosols produced from laser heated MOX the plutonium concentration decrease with aerosol size. • The specific properties of UO 2 and PuO 2 affects the formation of aerosols leading to elemental enrichment in the aerosols. • The collected EELS data on the smallest aerosols <20 nm shows that they are composed of pure uranium oxide. [ABSTRACT FROM AUTHOR]