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Maria C.M. Alvim-Ferraz

Bio: Maria C.M. Alvim-Ferraz is an academic researcher from University of Porto. The author has contributed to research in topics: Indoor air quality & Biodiesel. The author has an hindex of 42, co-authored 127 publications receiving 6282 citations. Previous affiliations of Maria C.M. Alvim-Ferraz include Faculdade de Engenharia da Universidade do Porto.


Papers
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TL;DR: It is evident from the revision made that AC prepared from both conventional and non-conventional wastes might effectively compete with the commercial ones.

905 citations

Journal ArticleDOI
TL;DR: In this article, the authors review the recent developments on the carbon capture and storage (CCS) methodologies from 2006 until now, focusing on the basic findings achieved in CCS operational projects.
Abstract: The Intergovernmental Panel on Climate Change assumes the warming of the climate system, associating the increase of global average temperature to the observed increase of the anthropogenic greenhouse gas (GHG) concentrations in the atmosphere. Carbon dioxide (CO 2 ) is considered the most important GHG, due to the dependence of world economies on fossil fuels, since their combustion processes are the most important sources of this gas. CO 2 concentrations are increasing in the last decades mainly due to the increase of anthropogenic emissions. The processes involving CO 2 capture and storage is gaining attention on the scientific community as an alternative for decreasing CO 2 emission, reducing its concentration in ambient air. However, several technological, economical and environmental issues as well as safety problems remain to be solved, such as the following needs: increase of CO 2 capture efficiency, reduction of process costs, and verification of environmental sustainability of CO 2 storage. This paper aims to review the recent developments (from 2006 until now) on the carbon capture and storage (CCS) methodologies. Special attention was focused on the basic findings achieved in CCS operational projects.

608 citations

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TL;DR: The main objective of this study was to list and compare the advantages and disadvantages of different methodologies to modify the surface of activated carbons for their application as adsorbents to remove organic and inorganic pollutants from aqueous phase.

484 citations

Journal ArticleDOI
TL;DR: Predicting next day hourly ozone concentrations through a new methodology based on feedforward artificial neural networks using principal components as inputs improved both models prediction by reducing their complexity and eliminating data collinearity.
Abstract: The prediction of tropospheric ozone concentrations is very important due to the negative impacts of ozone on human health, climate and vegetation. The development of models to predict ozone concentrations is thus very useful because it can provide early warnings to the population and also reduce the number of measuring sites. The aim of this study was to predict next day hourly ozone concentrations through a new methodology based on feedforward artificial neural networks using principal components as inputs. The developed model was compared with multiple linear regression, feedforward artificial neural networks based on the original data and also with principal component regression. Results showed that the use of principal components as inputs improved both models prediction by reducing their complexity and eliminating data collinearity.

472 citations

Journal ArticleDOI
TL;DR: A promising technology is the biological capture of CO 2 using microalgae as mentioned in this paper, which has the following advantages: (i) being an environmental sustainable method; (ii) using directly the solar energy; and (iii) co-producing high added value materials based on biomass, such as human food, animal feed, medical drugs, fertilizers, biomolecules for specific applications and biofuels.
Abstract: Carbon dioxide (CO 2 ) is one of the most important contributors for the increase of the greenhouse effect. CO 2 concentrations are increasing in the last decades mainly due to the increase of anthropogenic emissions. To reduce the effects caused by this environmental problem, several technologies were studied to capture CO 2 from large emission source points: (i) absorption; (ii) adsorption; (iii) gas-separation membranes; and (iv) cryogenic distillation. The resulting streams with high CO 2 concentrations are transported and stored in geological formations. However, these methodologies, known as carbon capture and storage (CCS) technologies, are considered as short-term solutions, as there are still concerns about the environmental sustainability of these processes. A promising technology is the biological capture of CO 2 using microalgae. These microorganisms can fix CO 2 using solar energy with efficiency ten times greater than terrestrial plants. Moreover, the capture process using microalgae has the following advantages: (i) being an environmental sustainable method; (ii) using directly the solar energy; and (iii) co-producing high added value materials based on biomass, such as human food, animal feed mainly for aquaculture, cosmetics, medical drugs, fertilizers, biomolecules for specific applications and biofuels. Approaches for making CO 2 fixation by microalgae economically competitive in comparison with CCS methodologies are discussed, which includes the type of bioreactors, the key process parameters, the gaseous effluents and wastewater treatment, the harvesting methods and the products extracted by microalgal biomass.

378 citations


Cited by
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Journal ArticleDOI
TL;DR: It is evident from the literature survey articles that ion-exchange, adsorption and membrane filtration are the most frequently studied for the treatment of heavy metal wastewater.

6,844 citations

Journal ArticleDOI
TL;DR: From a comprehensive literature review, it was found that some LCAs, in addition to having wide availability, have fast kinetics and appreciable adsorption capacities too.

3,163 citations

Journal Article
TL;DR: A case study explores the background of the digitization project, the practices implemented, and the critiques of the project, which aims to provide access to a plethora of information to EPA employees, scientists, and researchers.
Abstract: The Environmental Protection Agency (EPA) provides access to information on a variety of topics related to the environment and strives to inform citizens of health risks. The EPA also has an extensive library network that consists of 26 libraries throughout the United States, which provide access to a plethora of information to EPA employees, scientists, and researchers. The EPA implemented a reorganization project to digitize their materials so they would be more accessible to a wider range of users, but this plan was drastically accelerated when the EPA was threatened with a budget cut. It chose to close and reduce the hours and services of some of their libraries. As a result, the agency was accused of denying users the “right to know” by making information unavailable, not providing an adequate strategic plan, and discarding vital materials. This case study explores the background of the digitization project, the practices implemented, and the critiques of the project.

2,588 citations

Journal ArticleDOI
TL;DR: In this article, the main factors affecting the yield of biodiesel, i.e. alcohol quantity, reaction time, reaction temperature and catalyst concentration, are discussed, as well as new new processes for biodiesel production.

2,207 citations