0000000001206524

AUTHOR

J. Vergara

Effect of disorder produced by cationic vacancies at theBsites on the electronic properties of mixed valence manganites

An alloy series of single-phased polycrystalline ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Na}}_{x}{\mathrm{MnO}}_{3+\mathrm{\ensuremath{\delta}}} (0l~xl~0.15)$ has been synthesized in order to study the effect of disorder on the electronic properties of mixed valence manganites. The synthetic variables allow one to maintain a constant proportion of ${\mathrm{Mn}}^{4+}$ in the samples $({\mathrm{Mn}}^{3+}{/\mathrm{M}\mathrm{n}}^{4+}=2.1\ifmmode\pm\else\textpm\fi{}0.2),$ while the similar size of ${\mathrm{La}}^{3+}$ and ${\mathrm{Na}}^{+}$ ions results in no appreciable change in the tolerance factor of the perovskite structure throughout the series. In this way, the sodium content x contro…

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Applications of the X-ray fluorescence analysis to the cultural patrimony of the Comunidad Valenciana (Spain): Painting, metal and paper

We present examples of the application of the X-ray fluorescence (XRF) to the study of the artistic and cultural patrimony of the Comunidad Valenciana in the following areas: a) Valencian paintings of the XV and XVI centuries; b) silver ornaments coming from Iberian towns (s. III b.C.); c) ink and paper samples in manuscripts and engravings of the XVII and XIX centuries. The non destructive analyses are carried out “in situ” using a XRF system that consists of a tube of X-rays of 50 kV and 1 mA, and a detector of Si(Li) with an energy resolution 140 eV (FWHM at 5.9 keV).

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Assessment of the worldwide burden of critical illness: The Intensive Care Over Nations (ICON) audit

Item does not contain fulltext BACKGROUND: Global epidemiological data regarding outcomes for patients in intensive care units (ICUs) are scarce, but are important in understanding the worldwide burden of critical illness. We, therefore, did an international audit of ICU patients worldwide and assessed variations between hospitals and countries in terms of ICU mortality. METHODS: 730 participating centres in 84 countries prospectively collected data on all adult (>16 years) patients admitted to their ICU between May 8 and May 18, 2012, except those admitted for fewer than 24 h for routine postoperative monitoring. Participation was voluntary. Data were collected daily for a maximum of 28 da…

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