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Face values

A review of In Your Face — The New Science of Human Attraction by David Perrett. Palgrave Macmillan Press (2010), 272 pages, £14.99 ($55.00). ISBN: 0230201296 (hardback)

Journal of Evolutionary Psychology
Author: Antonio S. Silva
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Abstract  

A radiochemical method to isolate99Mo from132Te, both produced in the fission of235U, has been developed. The method is based on the formation of a cationic complex of tellurium with thiourea in acid medium which is retained (98.7±0.5)% on a cation exchange resin (Dowex 50W-X8, 100–200 mesh), while (99.8±0.05)%99Mo passes through it, due to the non-formation of such complex in the same experimental conditions. The radionuclidic purity of99Mo was found to be suitable for the preparation of99Mo–99mTc generators. The retention of99Mo on an alumina column as a function of pH was investigated and the best pH range for this purpose was found to be 4.0–4.5.

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Abstract  

We show that separable, locally compact spaces with property (a) necessarily have countable extent — i.e., have no uncountable closed, discrete subspaces — if the effective weak diamond principle ⋄(ω,ω,<) holds. If the stronger, non-effective, diamond principle Φ(ω,ω,<) holds then separable, countably paracompact spaces also have countable extent. We also give a short proof that the latter principle implies there are no small dominating families in ω 1 ω.

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Abstract

Alumina-based pigments were synthesized by the proteic sol–gel method. In this method, coconut water is employed as polymeric agent instead of the conventional alkoxide precursors. To this study, three common chromophore metallic ions (Mn3+, Co3+, and Cr3+) were chosen in order to verify the method efficiency. Differential thermal analysis (DTA), thermogravimetry (TG), and XRD techniques were used to characterize the synthesis process. The colorimetric characterization of the produced pigments was done according to the CIE-L*a*b* 1976 norm which is recommended by the CIE (International Commission on Illumination). The synthesized pigments presented intense and uniform colors in accordance to the literature results for each chromophore ion. The produced pigments also presented agglomerated with an average grain size of 180 nm when calcined at 800 °C.

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Journal of Thermal Analysis and Calorimetry
Authors: S. Silva, M. Conceiçăo, A. Souza, S. Prasad, M. Silva, V. Fernandes, A. Araújo, and F. Sinfrônio

Abstract  

The powder and the bran of algaroba pods, submitted to drying temperatures of 55, 65, 75, 85, 95 and 105C, were studied by conventional and thermogravimetric methods. The dynamic thermogravimetric curves of the samples indicated the following thermal stability order: 105>55>65>95>85>75C. The powder and the bran of algaroba pods, dried at 55C, presented protein content higher and isothermal thermogravimetric profiles comparable. The calorimetric curves of samples, dried at 55C, indicated the gelatinization of starch.

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Abstract  

A sediment core from an estuarine area receiving drainage from the highly industrialized Cubatão River basin (SE Brazil) showed 226Ra and 210Pb activities up to 80 and 213 Bq kg−1, respectively, which are greater than activities considered as regional background levels. Radionuclides and the elevated phosphorus concentrations (up to 0.3% sediment dry weight) found along the sediment core were significantly correlated with each other, indicating source similarity. These results indicate that 226Ra and 210Pb activities are affected by fertilizer industry-derived inputs in addition to natural sources. This interpretation was supported by 210Pb/226Ra ratios (found to be between 2.6 and 3.9) that indicate disequilibrium between 226Ra and its decay product 210Pb, as expected for phosphogypsum-affected sediments.

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Abstract  

This work reports the radioiodination of human thyrotropin (hTSH) in our laboratory (IPEN) and evaluates its quality in comparison with a commercial product. The radioiodination yield obtained in 20 experiments ranged from 18.5 to 56.3%, while the purification recovery ranged from 75.5 to 124.0% and the specific activity ranged from 1.01 to 3.10 MBq g–1. The values for the distribution coefficient revealed in the purification of radioiodinated hTSH ranged from 0.232 to 0.371. When tested concomitantly in the same radioimmunoassay system, the IPEN and the commercial tracer presented parallel standard curves. A highly significant correlation ion was observed between the quality control samples estimated through both curves (p<0.001). These results confirm the quality of the hTSH radioiodinated at IPEN and suggest the acquirement of self-sufficiency in this in vitro nuclear technology.

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