LOCAL DISORDER IN THE STRUCTURE OF BA(TI,CE)O3 PEROVSKITE BY MEANS OF POWDER DIFFRACTION AND TOTAL SCATTERING. EFFECT OF TEMPERATURE, DOPING CONCENTRATION AND GRAIN SIZE.

Nowadays BaTiO3 is considered as one of the most relevant environmental-friend ferroelectric and, thank to the chemical substitutions at the Ba2+ and/or Ti4+ sites, its properties are usually tailor to meet a big variety of devices and performance requirements. A classical example is the solid solution BaTi1-xMIVxO3, where M could be Sn, Zr, Hf, Ce etc., whose ferroelectric behavior shows an almost continuous variation with composition. The study of these compounds is then essential to improve their characteristics and make their suitable in more applications. Considering that their properties are deeply linked to the structure and especially to structural defects, average and local structural analyses are essential to better understand the origins of different polar behaviours and to have a real control on these materials. Despite this need, only BaTi1-xZrxO3 (BTZ) system, which is one of the most popular dielectrics used in multilayer ceramic capacitors, has been investigated in some detail. Although the similarity to BTZ suggests that BaTi1-xCexO3 (BTC) may be promising as lead free actuator materials, studies on this solid solution are almost limited. Thus in this research the BTC solid solution has been structurally investigated in order to provide knowledge lacks. Different ceramic samples with different doping amounts and different polar behaviours (from normal ferroelecric to relaxor via diffuse phase transition) have been investigated at different temperatures. In addition, taking into account the current tendency in miniaturized devices required in microelectronics, also chemical equivalent nano powders have been considered to explore not only doping effects, but also that of size. Pair Distribution Function (PDF) with different type of approaches (as carbox, biphasic and so on) has been employed coupled with TEM analysis and Raman spectroscopy. A complete description of that BaTi1-xCexO3 materials is given underlining links between polar behaviours, temperature, doping and size effects

Near Infrared Spectroscopy to Assess Feeding Value and Antinutritional Compounds in Legume Species

There is an increasing demand for information on the quality characteristics and chemical composition of forages in order to meet the demands of dietary specifications for feeding animals. Near Infrared (NIR) spectroscopy provides a tool for rapid and non-destructive analysis in agronomic and breeding programs of a number of chemical components of forages and grains. NIR spectroscopy in particular has the advantage of being able to simultaneously evaluate the samples for a number of qualitative traits of whole plants and seeds. In two experiments here presented, NIR Spectroscopy was used to predict: i) qualitative characteristics of field pea seeds and, as regards secondary metabolites responsible of detrimental or beneficial effects on animal nutrition ii) condensed tannins in legume forages, based on calibration sets of samples previously chemically analysed

Fabrication and magnetic properties of hard/soft magnetostatically coupled FePt/FeNi multilayer microwires

3 pages, 5 figures.-- PACS: 75.70.Cn; 75.60.Ej; 75.50.Ww; 81.15.Pq; 68.65.Ac; 81.40.EfA family of multilayer microwires with hard/soft biphase magnetic behavior is here introduced. The microwires consist of a Fe63Pt27Si10 hard magnetic nucleus and a Fe20Ni80 soft outer shell separated by an intermediate insulating Pyrex glass microtube. The precursor FePtSi glass-coated microwire is fabricated by quenching and drawing technique, and its L10 hard magnetic phase is grown by postannealing treatment technique. The polycrystalline FeNi soft magnetic outer shell has been deposited by electroplating. The analysis of the low-field hysteresis loops of the FeNi soft phase after premagnetizing until near magnetic saturation provides information about the magnetostatic coupling between phases. The FeNi magnetization curve is shifted toward positive field when the FePt remanent magnetization is positive and vice versa. A systematic analysis of the magnetostatic coupling and the corresponding bias field arising from uncompensated poles of the premagnetized FePt hard phase has been performed. The strength of the bias field is shown to increase with the reduction of thickness of the FeNi layer. These magnetostatically coupled biphase systems are thought to be of large potential interest as sensing elements in sensor devices.The work has been developed under the Project No. MAT2004-00150 supported by the Spanish Ministry of Education and Science, MEC. J. T. acknowledges a FPU program fellowship from MEC.Peer reviewe

Ce-exchange capacity of zeolite L in different cationic forms: a structural investigation

Cerium exchange by microporous materials, such as zeolites, has important applications in different fields, for example, rare earth element recovery from waste or catalytic processes. This work investigated the Ce-exchange capacity of zeolite L in three different cationic forms (the as-synthesized K form and Naand NH4-exchanged ones) from a highly concentrated solution. Chemical analyses and structural investigations allowed determination of the mechanisms involved in the exchanges and give new insights into the interactions occurring between the cations and the zeolite framework. Different cation sites are involved: (i) K present in the original LTL in the cancrinite cage (site KB) cannot be exchanged; (ii) the cations in KD (in the 12-membered ring channel) are always exchanged; while (iii) site KC (in the eight-membered ring channel) is involved only when K+ is substituted by NH4+, thus promoting a higher exchange rate for NH4+ -> K+ than for Na+ -> K+. In the Ce-exchanged samples, a new site occupied by Ce appears in the centre of the main channel, accompanied by an increase in the number of and a rearrangement of H2O molecules. In terms of Ce exchange, the three cationic forms behave similarly, from both the chemical and structural point of view (exchanged Ce ranges from 38 to 42% of the pristine cation amount). Beyond the intrinsic structural properties of the zeolite L framework, the Ce exchange seems thus also governed by the water coordination sphere of the cation. Complete Ce recovery from zeolite pores was achieved

Exploration of virtual body-representation in adolescence : the role of age and sex in avatar customization

The malleable nature of the self led researchers to investigate the meaning of virtual identity by exploring virtual self-representation through avatars and its association with users\u2019 identity. The present study aims to investigate the changes in virtual body-representation in adolescence related to age levels and sex and the association with adolescents\u2019 self-esteem and body esteem. Anthropometric features, body esteem and self-esteem were used to assess adolescents\u2019 body image and identity. The scoring code of the \u201cDrawing Me\u201d graphical test was used to evaluate the avatars. The sample is composed of 63 adolescents of different ages\u2014early, middle and late adolescence\u2014balanced by sex. Results show that the creation of a digital avatar changes with age and is partially associated with adolescents\u2019 perceptions in terms of body esteem and self-esteem. Moreover, the creation of avatars occurs differently for boys, who enrich their avatars with many sexual features, than for girls, who prefer to detail their avatars\u2019 clothing to enrich them. Critical reflections and implications for psychological interventions that may use avatars to investigate adolescents\u2019 identity in integration with other tools will be discussed

Magnetic anisotropy in ordered textured Co nanowires

The following article appeared in Applied Physics Letters 100.25 (2012): 252405 and may be found at http://scitation.aip.org/content/aip/journal/apl/100/25/10.1063/1.4729782The magnetization reversal in ordered arrays of Co nanowires with tailored hcp-phase texture, controlled by pH synthesis and nanowires length, has been investigated. The angular dependence of coercivity has been experimentally determined for different crystal textures, and the corresponding magnetization reversal mode is interpreted by analytical modelling. The results show that reversal takes place by propagation of a transverse-like domain wall mode. The fitting of experimental and calculated data allows us the quantitative evaluation of the magnetocrystalline anisotropy constant strength whose magnetization easy direction evolves from parallel to the wires toward in-plane orientation with the change of hcp-phase textureThe project has been performed under bilateral Chile-Spain project 2010CL0018. Additional financial support is acknowledged from the Spanish Ministry of Science and Innovation, MICINN, and MAT2010-20798-C05-01. Financial support from FONDECYT No. 1110784, Grant ICM P10-061-F by Fondo de Innovación para la Competitividad-MINECON and Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia, under project FB0807

Prediction of the chemical composition and nutritive value of lucerne (Medicago sativa L.) by Near Infrared Spectroscopy

Lucerne is a low input energy efficient crop that improves soil fertility, and its importance is rising with the increase of public interest in sustainable agriculture. Furthermore, it occupies a significant economic position in the animal feed market (i.e. hay, dehydrated forage, pellets and silage products) and deserves a particular interest in the Parmigiano-Reggiano and Grana Padano cheese production areas of Northern Italy (Torricelli et al., 2000)

Editorial: Evolution in respiratory pharmacology

This collection of Research Topics entitled “Evolution in respiratory pharmacology,” involving authors from several countries, confirms that “Respiratory Pharmacology” is a current topic in clinical and research settings. All articles focused on contributions that explore the changing context and emerging new perspectives within Respiratory Pharmacology (Kim et al., Cerqua et al., Li et al., Lin et al., Zhang et al.). The emphasis of this Research Topic is on the dynamics of change and the evolution of the latest progress made in the field of Respiratory Pharmacology. This collection of articles aims to inform, inspire, and provide direction and guidance to researchers in the field

Induced sputum cellularity. Reference values and distribution in normal volunteers.

Abstract Sputum induction has recently been proposed as the only direct noninvasive method for measuring airway inflammatory indices. The reference values and the distribution of cells in induced sputum in a control population have not yet been well defined. We therefore evaluated data from a large number of healthy volunteers. One hundred fourteen healthy, nonatopic, nonsmoking volunteers without airway hyperreactivity were enrolled (age: 38 +/- 13 yr [mean +/- SD]; FEV(1): 105 +/- 10% predicted; provocative dose of methacholine inducing a 20% decrease FEV(1) > 3,200 microgram). Ninety-six subjects (84%) produced adequate analysis samples. The subjects had a normal age distribution. Their induced sputum was rich in macrophages (69.2 +/- 13%) and neutrophils (27.3 +/- 13%), and poor in eosinophils (0.6 +/- 0.8%), lymphocytes (1.0 +/- 1.2%), and epithelial cells (1.5 +/- 1.8%). Only macrophages and neutrophils showed a normal distribution; total and differential counts of other cells did not. We propose that these data be used in comparison of the induced sputum cells of normal subjects and those of patients with airway inflammation