Showing papers by "Maria C.M. Alvim-Ferraz published in 2014"
TL;DR: In this paper, the authors evaluated indoor concentrations of particulate matter (PM1, PM2.5, PM10 and PMTotal) on different indoor microenvironments in urban nurseries of Porto city, and analyzed those concentrations according to guidelines and references for indoor air quality and children's health.
76 citations
TL;DR: Although the microenvironmental (ME) modelling approach in studies to assess children's exposure to air pollution is highly encouraged, a validation process is needed, due to the uncertainties associated with the application of this approach.
50 citations
TL;DR: The presented results showed that microalgal culture is a promising strategy for CO2 capture from atmosphere if cultivated under higher irradiances than the studied values.
Abstract: Carbon dioxide (CO2) is one of the primary greenhouse gases that contribute to climate change. Consequently, emission reduction technologies will be needed to reduce CO2 atmospheric concentration. Microalgae may have an important role in this context. They are photosynthetic microorganisms that are able to fix atmospheric CO2 using solar energy with efficiency ten times higher than terrestrial plants. The objectives of this study were: (i) to analyse the effect of light supply on the growth of Chlorella vulgaris and Pseudokirchneriella subcapitata; (ii) to assess the atmospheric CO2 capture by these microalgae; and (iii) to determine the parameters of the Monod model that describe the influence of irradiance on the growth of the selected microalgae. Both microalgae presented higher growth rates with high irradiance values and discontinuous light supply. The continuous supply of light at the highest irradiance value was not beneficial for C. vulgaris due to photooxidation. Additionally, C. vulgaris achieved the highest CO2 fixation rate with the value of 0.305 g-CO2 L−1 d−1. The parameters of the Monod model demonstrated that C. vulgaris can achieve higher specific growth rates (and higher CO2 fixation rates) if cultivated under higher irradiances than the studied values. The presented results showed that microalgal culture is a promising strategy for CO2 capture from atmosphere.
33 citations
TL;DR: In this article, the authors used a very active calcium glyceroxide catalyst and purified using water-free processes to remove the main impurity of soaps from biodiesel, which was the main product impurity.
25 citations
TL;DR: In this article, the authors evaluate the effectiveness of water-free purification methods for the use of a cation-exchange resin and a ceramic membrane for water free purification.
19 citations
TL;DR: In this paper, the authors report the development of multiple linear regression and artificial neural network models to predict the remediation time and efficiency of soil vapor extractions performed in soils contaminated separately with benzene, toluene, ethylbenzene, xylene, trichloroethylene, and perchloro-ethylene.
Abstract: The prediction of the time and the efficiency of the remediation of contaminated soils using soil vapor extraction remain a difficult challenge to the scientific community and consultants. This work reports the development of multiple linear regression and artificial neural network models to predict the remediation time and efficiency of soil vapor extractions performed in soils contaminated separately with benzene, toluene, ethylbenzene, xylene, trichloroethylene, and perchloroethylene. The results demonstrated that the artificial neural network approach presents better performances when compared with multiple linear regression models. The artificial neural network model allowed an accurate prediction of remediation time and efficiency based on only soil and pollutants characteristics, and consequently allowing a simple and quick previous evaluation of the process viability.
10 citations