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Abstract  

In this paper the structural characterization of terfenadine crystallized from ethanol-water, ethanol and methanol is performed by infrared spectroscopy. The OH stretching vibration, composed of three markedly overlapped bands, is analyzed by peak fitting. The assignment of the hydrogen bonds was conducted making use of band parameters, spectroscopic data for CCl4 solutions, and molecular dynamics calculations from dimeric systems. Terfenadine just precipitated from solvents is never in the highest crystalline state. This state is reached when the samples are heated at a temperature above 100C. Some amorphous solid is coprecipitated with the crystalline phase, particularly in methanol.

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Journal of Thermal Analysis and Calorimetry
Authors: J. Amorim, S. Eliziário, D. Gouveia, A. Simőes, J. Santos, M. Conceiçăo, A. Souza, and M. Trindade

Abstract  

The thermogravimetry (TG) is a technique used in the quality control of foods. In this work the moisture and ash contents in the rice and by-products (bran and husk), the thermal stability and the gelatinization process by conventional, thermogravimetric and calorimetric methods were studied. The moisture and ash contents obtained by TG and conventional methods did not present significant differences. The rice presented higher starch content, while the bran presented higher protein content. The thermogravimetric data presented the following thermal stability order: rice>bran>husk. The calorimetric curves indicated the gelatinization of the starch. The kinetic parameters were compatible.

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Journal of Thermal Analysis and Calorimetry
Authors: D. Brito, E. Silva, D. Rodrigues, M. Machado, M. Silva, V. Simões, M. Carvalho, L. Soledade, Iêda Santos, and A. Souza

Abstract  

A silico alumino phosphate with AFI structure (SAPO-5) was prepared in a two-phase medium and characterized by XRD, followed by the addition of TEA+. The kinetics of the TEA+/SAPO-5 thermal decomposition reaction was studied by isothermal and dynamic thermogravimetry. Two kinetic models, D3 and D4 based on diffusion processes were found as best to fit the isothermal data. On the other hand, the best fit for the dynamic data is the F1 first order reaction model. According to the apparent activation energy values, the use of the dynamic method indicates a higher temperature dependence than the isothermal method.

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Scientometrics
Authors: Eduardo A. Oliveira, Enrico A. Colosimo, Daniella R. Martelli, Isabel G. Quirino, Maria Christina L. Oliveira, Leonardo S. Lima, Ana Cristina Simões e Silva, and Hercílio Martelli-Júnior

Abstract

Quantifying the relative performance of individual scholars has become an integral part of decision-making in research policy. The objective of the present study was to evaluate if the scholarship rank of Brazilian Council for Scientific and Technological Development (CNPq) researchers in Medicine is consistent with their scientific productivity. The Lattes curricula of 411 researchers (2006–2008) were included in the study. Scholarship category was the variable of interest. Other variables analyzed were: time since receiving the doctorate, teaching activity (undergraduate, master's and doctoral students), number of articles published, and number of papers indexed by the Institute for Scientific Information (ISI) and Scopus databases. Additional performance indicators included were: citations, h-index, and m-index. There was a significant difference among scholarship categories regarding number of papers per year, considering the entire scientific career (P < 0.001) or the last 5 years (P < 0.001). There was no significant difference among scholarship categories regarding the number of citations per article in the ISI (Thomson Reuters) database (P = 0.23). There was a significant difference in h-index among scholarship categories in both databases, i.e. (P < 0.001) and Scopus (P < 0.001). Regarding the m-index, there was a significant difference among categories only in the ISI database (P = 0.012). According to our findings, a better instrument for qualitative and quantitative indicators is needed to identify researchers with outstanding scientific output.

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