4 resultados para Star properties

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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We study the equation of state for neutron matter using the Walecka model including quantum corrections for baryons and sigma mesons through a realignment of the vacuum. We next use this equation of state to calculate the radius, mass and other properties of rotating neutron star.

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This paper reports our initial research to obtain SrWO4 microcrystals by the injection of ions into a hot aqueous solution and their photocatalytic (PC) properties. These microcrystals were structurally characterized by X-ray diffraction (XRD), Rietveld refinements and Fourier transform (FT)-Raman spectroscopy. The shape and average size of these SrWO 4 microcrystals were observed by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). In addition, we have investigated the PC activity of microcrystals for the degradation of rhodamine B (RhB) and rhodamine 6G (Rh6G) dyes. XRD patterns, Rietveld refinement data and FT-Raman spectroscopy confirmed that SrWO4 microcrystals have a scheelite-type tetragonal structure without deleterious phases. FT-Raman spectra exhibited 12 Raman-active modes in a range from 50 to 1000 cm-1. FE-SEM and TEM images suggested that the SrWO4 microcrystals (rice-like - 95%; star-, flower-, and urchin-like - 5%) were formed by means of primary/secondary nucleation events and self-assembly processes. Based on these FE-SEM/TEM images, a crystal growth mechanism was proposed and discussed in details in this work. Finally, a good PC activity was first discovered of the SrWO4 microcrystals for the degradation of RhB after 80 min and Rh6G after 50 min dyes under ultraviolet-light, respectively. © 2012 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder.

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The present research was undertaken to explore the influence of fructooligosaccharides (FOS) on the functional and thermal properties of sour cassava starch and the quality characteristics of gluten-free (GF) cheese bread. Fructooligosaccharides were used to replace sour cassava starch at substitution level of 9% (SF1), 17% (SF2), and 29% (SF3). The functional and thermal properties of the starch-FOS mixtures were determined by the water absorption index (WAI), water solubility index (WSI), pasting profile analysis, thermal transition temperatures and enthalpy of gelatinization. Moreover, the GF cheese breads with starch-FOS mixtures were analyzed for height, diameter, weight, specific volume and dough moisture content. The sample with the highest FOS content (SF3) presented the lowest WAI (1.44), peak (62.4 rapid visco units (RVU), breakdown (53.4 RVU), final (13.8 RVU), and setback (4.9 RVU) viscosities, dough moisture content (31.7%), and enthalpy of gelatinization (9.5 J/g) and the highest WSI (29.4%) and pasting temperature (69.1 degrees C). The height, diameter and specific volume of GF cheese bread samples made from sour cassava starch were 3.14 cm, 6.35 cm, and 1.49 cm(3)/g, respectively. The SF1 mixture samples resulted in a 3.01 cm height, 6.34 cm diameter, and 1.55 cm(3)/g specific volume. According to Brazilian food labeling regulations, the latter product cannot be categorized as a good source of fiber because the minimum level of fiber per portion was not reached.