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- Tecnologias ambientais: resíduosPublication . Ferreira, CéliaBreve introdução aos resíduos, sua classificação e perigosidade, assim como às operações e processos unitários da gestão de resíduos.
- Distribution and bioconcentration of heavy metals in a tropical aquatic food web: a case study of a tropical estuarine lagoon in SE MexicoPublication . Carranza, Manuel Mendoza; Lozada, Alejandra Sepulveda; Ferreira, Célia; Geissen, VioletteDespite the increasing impact of heavy metal pollution in southern Mexico due to urban growth and agricultural and petroleum activities, few studies have focused on the behavior and relationships of these pollutants in the biotic and abiotic components of aquatic environments. Here, we studied the bioaccumulation of heavy metals (Cd, Cr, Ni, Pb, V, Zn) in suspended load, sediment, primary producers, mollusks, crustaceans, and fish, in a deltaic lagoon habitat in the Tabasco coast, with the aim to assess the potential ecological risk in that important wetland. Zn showed the highest concentrations, e.g., in suspended load (mean of 159.58 mg kg 1 ) and aquatic consumers (15.43e171.71 mg kg 1 ), particularly Brachyura larvae and ichthyoplankton (112.22e171.71 mg kg 1 ), followed by omnivore Callinectes sp. crabs (113.81e128.07 mg kg 1 ). The highest bioconcentration factors (BCF) of Zn were observed for planktivore and omnivore crustaceans (3.06e3.08). Zn showed a pattern of distribution in the food web through two pathways: the pelagic (where the higher concentrations were found), and the benthic (marsh plants, sediment, mollusk, fish). The other heavy metals had lower occurrences in the food web. Nevertheless, high concentrations of Ni and Cr were found in phytoplankton and sediment (37.62 e119.97 mg kg 1 ), and V in epiphytes (68.64 mg kg 1 ). Ni, Cr, and Cd concentrations in sediments surpassed international and national threshold values, and Cd entailed a “considerable” potential risk. These heavy metals are most likely transferred into the food web up to fishes through the benthic pathway. Most of the collected fishes are residents in this type of habitat and have commercial importance. Our results show that the total potential ecological risk in the area can be considered as “moderate”. Nevertheless, heavy metal values were similar or surpassed the values from other highly industrialized tropical coastal regions.
- Enhanced transport and transformation of zero-valent nanoiron in clay using direct electric currentPublication . Gomes, Helena I.; Ferreira, Célia; Ribeiro, Alexandra B.; Pamukcu, SibelOne of the major obstacles to zerovalent iron nanoparticles (nZVI) application in soil and groundwater remediation is the limited transport, especially in low-permeability soils. In this study, direct current (constant potential of 5.0 V) was used to enhance polymer-coated nZVI mobility in different porous media, including a bed of glass beads and kaolin clay. The tests were conducted using a modified electrophoretic cell and with nZVI concentrations typical of field applications (4 g L−1 ). Experimental results indicate that the use of direct current can enhance the transport of the polymer-modified nanoparticles when compared with natural diffusion in low permeability or surface neutral porous medium. The applied electric field appeared to enhance the oxidation–reduction potential, creating a synergistic effect of nZVI usage with electrokinetics. Aggregation of the nanoparticles, observed near the injection point, remained unresolved.
- Manual para aulas com realidade virtualPublication . Makrides, Gregory; Aufenanger, Stefan; Bastian, Jasmin; Damianos, Gavalas; Vlasis, Kasapakis; Apostolos, Kostas; Solarz, Pawel; Szemberg, Tomasz; Szpond, Justyna; Bastos, Glória; Castelhano, Maria; Ferreira, Célia; Morgado, Leonel; Pedrosa, Daniela
- Tag & sensoring solutions overview for smart cities waste managementPublication . Madureira, R. C.; Ferreira, CéliaThis paper describes the technology behind the implementation of smart waste management systems at the starting point of collecting information about the user and the amount of produced waste. This analysis is based on new technological approaches framed by the smart city concept and often associated to the pay-as-you-throw (PAYT) conceptions. We begin with an overview of the current available technologies with examples of real applications, with a glance on the costs/benefit and system’s limitations. We conclude with suggestions for further research on technology approaches to support best practices both for municipal policies and citizen’s behavior. The results show how pertinent is the developing of reliable systems to help decision makers managing waste smartly towards a truly smart city concept.
- O (In)sucesso da recolha seletiva em Portugal: relatório técnico do 1º Seminário de ResíduosPublication . Ferreira, Célia; Nunes, Isabel; Góis, José Carlos; Oliveira, Verónica
- Are municipal waste utilities becoming sustainable? A framework to assess and communicate progressPublication . Fernández Braña, Álvaro; Sousa, Vítor; Ferreira, CéliaA framework of indicators to assess the progress towards sustainability of municipal waste management utilities is developed. Its purpose is to fulfil the need for assessing the performance of municipal waste (MW) management in a simple but comprehensive way—unlike indicators based on individual aspects such as recycling—and including aspects not well considered before, such as waste prevention. The framework is composed of a set of six single indicators, concerning the three dimensions of sustainability: reduction of effectively landfilled MW and reduction of MW generation (environmental component), balance between expenses and revenues and reduction of costs (economic component), accessibility to separate collection and number of complaints (social component). Each indicator consists of an evaluation of the current status of the variable in contrast to a previous situation, with a positive value in case of improvement or negative in case of decline. Then, the values of the individual indicators are combined to obtain a global result. This approach focuses on dynamic progress towards sustainability, complementing the common static indicators. Contrarily to the existing performance indicator schemes, the proposed framework aims at measuring the progress and not the absolute or relative achievement of a waste management utility. The framework was tested on two Portuguese municipalities, proving to be a straightforward application and reliable in guiding stakeholders. Results for the case study showed good performance on economic sustainability, while environmental and social performance were lower due to a lack of strategies for waste prevention and low source separation, affected by poor accessibility to separate collection.
- Recolha comunitária de lixo em São Tomé e Príncipe: guia de implementação de um modelo descentralizado e auto-sustentável ao nível da comunidadePublication . Fernández Braña, Álvaro; Ferreira, CéliaEste Guia de Implementação pretende apoiar à colocação em prática de um sistema de recolha de resíduos urbanos a pequena escala (a nível de bairro ou comunidade) em locais onde não há recolha de resíduos por parte das autoridades locais ou onde esta existe mas não dá resposta às necessidades da população. O modelo baseia-se numa recolha de resíduos feita pela própria comunidade, sem a dependência financeira de ajuda externa.