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The Barium (BSCF) and Lanthanum (LSCF) strontium cobalt–ferrite, are among the most studied mixed ionic electronic conducting materials having interesting properties as Oxygen Transport Membranes. In this paper the two materials are analysed after long term aging at high temperatures and permeation tests. Several characterisation techniques are used to understand degradation mechanisms. Surface layers were analysed by X-ray photoelectron spectroscopy: LSCF is stable, while on BSCF a thin layer of carbonates forms. Quantitative synchrotron radiation diffraction measurements of hexagonal phase content in aged BSCF allows determining Avrami coefficients at 780, 800 and 820 °C. This process is associated to the enrichment of Fe in the regions of grains near the lamellar hexagonal phase, as WDS maps show. Bulk measurements of X-ray Absorption Near Edge Structure (XANES) and the analysis of the Co2p doublet in XPS spectra confirm a reduction of Co ions oxidation number after long time at intermediate temperatures.

Starting in 2011, the North Italy Transplant program (NITp) has based on the allocation of pancreas allografts on donor age and duration of intensive care unit (ICU) stay, but not on donor weight or BMI. We analyzed the detailed allocation protocols of all NITp pancreas donors (2011-2012; n = 433). Outcome measures included donor characteristics and pancreas loss reasons during the allocation process. Twenty-three percent of the 433 pancreases offered for allocation were transplanted. Younger age, shorter ICU stay, traumatic brain death, and higher eGFR were predictors of pancreas transplant, either as vascularized organ or as islets. Among pancreas allografts offered to vascularized organ programs, 35% were indeed transplanted, and younger donor age was the only predictor of transplant. The most common reasons for pancreas withdrawal from the allocation process were donor-related factors. Among pancreas offered to islet programs, 48% were processed, but only 14.2% were indeed transplanted, with unsuccessful isolation being the most common reason for pancreas loss. Younger donor age and higher BMI were predictors of islet allograft transplant. The current allocation strategy has allowed an equal distribution of pancreas allografts between programs for either vascularized organ or islet transplant. The high rate of discarded organs remained an unresolved issue. © 2013 Steunstichting ESOT.