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Lead iodide (PbI 2) is a semiconductor with extensive use as an active layer for X-ray detectors and as a precursor for perovskite solar cells. Here we present a low vacuum method to obtain very uniform PbI 2 films with full substrate coverage. This method consists in the sublimation of PbI 2 inside a hot zone and its transport by an Ar flow to a substrate held at a controlled temperature. Using scanning electron microscopy combined with focused ion beam and X-ray diffraction we studied the morphology and crystallographic structure of the PbI 2 films with different deposition parameters: substrate and source evaporation temperature, deposition time and substrate material. At high substrate temperature (80ºC) and low evaporation temperature (310ºC) onto a glass sample, we obtained dense and smooth PbI 2 films showing hexagonal crystals, or platelets, stacked parallel to the substrate. The choice of the substrate material has a significant impact on the film morphology yielding porous-like structures with voids within the films for some substrates. A bandgap E g = 2.42 eV and Urbach energy

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The feasibility of the application of chemometric techniques associated with multi-element analysis for the classification of grape seeds according to their provenance vineyard soil was investigated. Grape seed samples from different localities of Mendoza province (Argentina) were evaluated. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of twenty-nine elements (Ag, As, Ce, Co, Cs, Cu, Eu, Fe, Ga, Gd, La, Lu, Mn, Mo, Nb, Nd, Ni, Pr, Rb, Sm, Te, Ti, Tl, Tm, U, V, Y, Zn and Zr). Once the analytical data were collected, supervised pattern recognition techniques such as linear discriminant analysis (LDA), partial least square discriminant analysis (PLS-DA), k-nearest neighbors (k-NN), support vector machine (SVM) and Random Forest (RF) were applied to construct classification/discrimination rules. The results indicated that nonlinear methods, RF and SVM, perform best with up to 98% and 93% accuracy rate, respectively, and therefore are excellent tools for classification of grapes.

Selenium (Se) is an essential element for humans and has anti-cancer function. Garlic can accumulate Se, so it is an option to Se supplementation in the human diet. The aim of this research was to study Se uptake and accumulation during garlic growth. Four doses of Na2SeO4 and Na2SeO3 solution were applied in the substrate (0, 5, 10 and 15 kg ha-1 Se) for one time in August 2014, with a random plot design and 3 replicates on garlic clone Rubi INTA. Three harvests were made, in September, October and December 2014. After each harvest, leaves, bulbs and roots were separated and conditioned (peeled and chopped), lyophilized, and finally acid-digested prior to Se, Mg, Zn, Mn, Cu, Fe, P and S determination by inductively coupled plasma mass spectrometry (ICP-MS). The Se accumulation was proportional to Se doses and did not affect garlic growth. Also, Se distribution among different organs was related to the garlic growth cycle. The Se presence decreased accumulation of Mg, Mn, Cu, Fe, P and S but increased Zn accumulation in plants. Garlic can be an important Se source to humans but it is important to consider Se-doses for biofortification.

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