Rietveld refinement, morphology and optical properties of (Ba 1-xSrx)MoO4 crystals

In this article, the structural refinement, morphology and optical properties of barium strontium molybdate [(Ba1-x Sr x )MoO4 with x = 0, 0.25, 0.50, 0.75 and 1] crystals, synthesized by the co-precipitation (drop-by-drop) method, are reported. The crystals obtained were structurally characterized by X-ray diffraction (XRD), Rietveld refinement, and Fourier transform-Raman (FT-Raman) and Fourier transform-infrared (FT-IR) spectroscopies. The shapes of the crystals were observed by means of field-emission scanning electron microscopy (FE-SEM). The optical properties were investigated using ultraviolet-visible (UV-Vis) absorption spectroscopy and photoluminescence (PL) measurements. XRD patterns, Rietveld refinement, and FT-Raman and FT-IR spectra showed that all of the crystals are monophasic with a scheelite-type tetragonal structure. The refined lattice parameters and atomic positions were employed to model the [BaO8], [SrO8] and [MoO4] clusters in the tetragonal lattices. The FE-SEM images indicate that increased x content produces a decrease in the crystal size and modifications in the crystal shape. UV-Vis spectra indicated a decrease in the optical band gap with an increase in x in the (Ba1-x Sr x )MoO4 crystals. Finally, a decrease in the intensity of PL emission is apparent with an increase in x up to 0.75 in the (Ba1-x Sr x )MoO4 crystal lattice when excited by a wavelength of 350nm, probably associated with the degree of structural order-disorder. © 2013 International Union of Crystallography Printed in Singapore - all rights reserved.

La estrategia cubana de la vuelta al campo: anhelos y opciones de los jóvenes rurales

Incluye Bibliografía

Programa de trabajo estadístico internacional para América Latina y el Caribe, 1995-1996: Subprograma 2: estadísticas e indicadores del medio ambiente = Programme of international statistical work for Latin America and the Caribbean, 1995-1996: Subprogramme 2: activities in the field of environment statistics and indicators

Incluye Bibliografía

Diapriinae (Hymenoptera, Diapriidae) da estação ecológica de Jatí, no município de Luiz Antônio

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Visibilidade dos pesquisadores no GT7 da ANCIB: um estudo de cocitações

This research aims at analyzing the researchers with major insertion and impact within the GT7 ENANCIB community, through an analysis study of citation and co-citation from 2003 to 2010. We propose to highlight the researchers cited in a greater number of papers, as well as the number of citations received. Also, to describe the co-citation network intending to analyze the interlocution network built by the writers towards the cited ones and calculate the indicators of density and centrality of the network. As for the theoretical-methodological basis, we used the Domain Analysis (D.A.), seen as the reflexion of a discourse community. Among the 11 approaches about D.A, the bibliometric studies stand out. Data from the 124 researches presented in the period of this study showed 1446 cited researches for a total of 2307 citations. From the total number of cited researchers in a greater number of papers, 33 were considered authors of major impact and visibility, being cited in at least 8 papers, thus getting at least 8 citations. The software Ucinet was used to map and visualize the net of interlocution established by the citing papers. As for the results, we could notice that, from the total of 33 researchers, 23 are Brazilian, 20 take part in Post-Graduation Programs and 11 are granted CNPq scholarships of productivity. Furthermore, we highlighted the most cited themes and analyzed the relationship involving the number of citations according to the number of papers in which the researcher was cited and the number of researches cited from each researcher. Regarding the network structure, we could observe that the authors form a single component, indicating that the group of researchers co-cited reveals proximity and theoretical, conceptual and methodological articulations. We concluded that the citing community adopts ordinary theoretical schools; moreover, we might characterize the core of the known researchers as a foundation for the knowledge of the GT7 theme.

Magnetic Purification of Curcumin from Curcuma longa Rhizome by Novel Naked Maghemite Nanoparticles

Naked maghemite nanoparticles, namely, surface active maghemite nanoparticles (SAMNs), characterized by a diameter of about 10 nm, possessing peculiar colloidal stability, surface chemistry, and superparamagnetism, present fundamental requisites for the development of effective magnetic purification processes for biomolecules in complex matrices. Polyphenolic molecules presenting functionalities with different proclivities toward iron chelation were studied as probes for testing SAMN suitability for magnetic purification. Thus, the binding efficiency and reversibility on SAMNs of phenolic compounds of interest in the pharmaceutical and food industries, namely, catechin, tyrosine, hydroxytyrosine, ferulic acid, coumaric acid, rosmarinic acid, naringenin, curcumin, and cyanidin-3-glucoside, were evaluated. Curcumin emerged as an elective compound, suitable for magnetic purification by SAMNs from complex matrices. A combination of curcumin, demethoxycurcumin, and bis-demethoxycurcumin was recovered by a single magnetic purification step from extracts of Curcuma longa rhizomes, with a purity >98% and a purification yield of 45%, curcumin being >80% of the total purified curcuminoids.

Nano-displacement measurements of a new piezoelectric flextensional actuator by using a high dynamic range interferometry homodyne method

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of the Computer-based Battery for Oral Language (BILOv3) through the Rasch model for a Brazilian Sample

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In vitro effect of sodium trimetaphosphate additives to conventional toothpastes on enamel demineralization

The aim of this study was to evaluate the ability of conventional toothpastes (1100 ppm F) supplemented with sodium trimetaphosphate (TMP) in demineralization. Blocks of enamel were selected and then divided into seven experimental groups of 12: toothpaste without F and TMP (placebo), toothpaste with 1100 ppm F (1100), and toothpaste with 1100 ppm F supplemented with TMP-1 % (1100 1 % TMP), 3 % (1100 3 % TMP), 4.5 % (1100 4.5 % TMP), 6 % (1100 6 % TMP), and 9 % (1100 9 % TMP). Blocks were subjected to five pH cycles (demineralizing/remineralizing solutions) at 37 °C and treated with toothpaste slurries twice daily, after which the blocks were maintained for 2 days in fresh remineralizing solution. Following treatments, surface hardness (SHf) and cross-sectional hardness were determined for calculating the integrated loss of subsurface hardness (ΔKHN). The fluoride present in the enamel was also measured. The SHf and ΔKHN measurements showed that supplementation with 3 % TMP was the most effective (p < 0.001) and showed greater concentration of F in the enamel (p < 0.001). Addition of 3 % TMP to a conventional toothpaste (1100 ppm F) showed greater efficacy in reducing enamel demineralization. Fluoride toothpastes containing trimetaphosphate possess good anticaries potential required to reduce the prevalence of dental caries in high-risk patients.

Seal, replacement or monitoring amalgam restorations with occlusal marginal defects? Results of a 10-year clinical trial

The aim of this prospective and blind clinical trial was to assess the effectiveness of sealing localized marginal defects of amalgam restoration that were initially scheduled to be replaced. A cohort of twenty six patients with 60 amalgam restorations (n=44Class I and n=16Class II), that presented marginal defects deviating from ideal (Bravo) according to USPHS criteria, were assigned to either sealing or replacement groups: A: sealing n=20, Replacement n=20, and no treatment (n=20). Two blind examiners evaluated the restorations at baseline (K=0.74) and after ten years (K=0.84) according with USPHS criteria, in four parameters: marginal adaptation (MA), secondary caries (SC), marginal staining (MS) and teeth sensitivity (TS). Multiple comparison of restorations degradation/upgrade was analyzed by Friedman test and the comparisons within groups were performed by Wilcoxon test. After 10 years, 44 restorations were assessed (73.3%), Group A: n=14 and Group B: n=16; and Group C: n=14 sealing and replacement amalgam restorations presented similar level of quality in MA (p=0.76), SC (p=0.25) and TS (p=0.52), while in MS (p=0.007) presented better performance in replacement group after 10-years. Most of the occlusal amalgam restorations with marginal gaps showed similar long term outcomes than the restorations were sealed, replaced, or not treated over a 10-year period. Most of the restorations of the three groups were clinically acceptable, under the studied parameters. All restorations had the tendency to present downgrade/deterioration over time.

Experiências com livros que exploram a sua materialidade: mediações e leituras possíveis

Pós-graduação em Artes - IA

Proposta de um programa de qualidade o leite e controle da mastite em rebanho bovino de vacas holandesas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Novas mediações folkcomunicacionais a partir da narrativa transmídia

Cultural events are changing significantly since the arrival of Web 2.0, where the company now has the ability to interact with the content available on the Internet, and also produce their own channels of media content. Among the existing manifestations, stands out by a bias folk-communicational, content production Comics, which consists in the narrative reconstruction of existing audiovisual products, making the author of the new work in an agent folkcommunicational. This article presents new perspectives on the issue, proposing a new reading of the mediations folk-communicational from transmedia storytelling.