Browsing by Author "Matos, Manuel"
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- Band-gap tunable thiadiazolo[3,4-g]quinoxaline derivatives as non-fullerene acceptors in organic photovoltaic cells processed from low toxic ethanol/anisole mixturesPublication . Costa, Cristiana; Farinhas, Joana; Velho, Mariana F. G.; Avo, Joao; Matos, Manuel; Galvão, Adelino; Charas, AnaThe synthesis, characterisation and application as electron-acceptors in organic photovoltaic cells of new [1,2,5]thiadiazolo[3,4-g]quinoxaline-based small molecules with oligo(ethylene oxide) solubilising groups and tunable optical bandgaps are reported. A new p-type polymer consisting of a polythiophene derivative substituted with analogous solubilising groups was also synthesised to perform as a donor, in combination with the small molecules, for bulk-heterojunction solar cells using ethanol/anisole mixtures as low toxic solvents to process the active blends. Comparison of the structural, electrochemical and photophysical properties of the small molecules elucidated on the structural dependence of their optical bandgaps, ranging from 1.31 to 2.25 eV. The active layers composed of the polythiophene donor and the small molecules showed well-intermixed morphologies, and the best performing blends showed a fibrillar-type morphology, indicative of more ordered molecular packings. Blends processed from the 50 : 50 (v/v) mixture of ethanol and a low toxic solvent, anisole, yielded low power conversion efficiencies of 0.39% in non-optimized organic solar cells. Although the efficiencies are low, these are the first reported results of OSCs with active layers composed of non-fullerene acceptors processed from ethanol-based solvent formulations. This study provides guidelines for the design of non-fullerene acceptors for the fabrication of OSCs processed from environmentally friendly solvents.
- Behaviour and fate of metals in urban wastewater treatment plants: a reviewPublication . Cantinho, Paula; Matos, Manuel; Maria A. Trancoso; Santos, M. M. Correia dosThe concerns on metals in urban wastewater treatment plants (WWTPs) are mainly related to its contents in discharges to environment, namely in the final effluent and in the sludge produced. In the near future, more restrictive limits will be imposed to final effluents, due to the recent guidelines of the European Water Framework Directive (EUWFD). Concerning the sludge, at least seven metals (Cd, Cr, Cu, Hg, Ni, Pb and Zn) have been regulated in different countries, four of which were classified by EUWFD as priority substances and two of which were also classified as hazardous substances. Although WWTPs are not designed to remove metals, the study of metals behaviour in these systems is a crucial issue to develop predictive models that can help more effectively the regulation of pre-treatment requirements and contribute to optimize the systems to get more acceptable metal concentrations in its discharges. Relevant data have been published in the literature in recent decades concerning the occurrence/fate/behaviour of metals in WWTPs. However, the information is dispersed and not standardized in terms of parameters for comparing results. This work provides a critical review on this issue through a careful systematization, in tables and graphs, of the results reported in the literature, which allows its comparison and so its analysis, in order to conclude about the state of the art in this field. A summary of the main consensus, divergences and constraints found, as well as some recommendations, is presented as conclusions, aiming to contribute to a more concerted action of future research. © 2015, Islamic Azad University (IAU).
- Determination of antioxidants and total polyphenols in cabbages (Brassica Oleracea) irrigated wiht wastewater contaminated with toxic metalsPublication . Silva, Hugo F.A.; Barreiros, Ana Maria; Silva, Nelson A. F.; Oliveira, Cristina; Coelho, Jose; Matos, ManuelWater is a natural resource essential to all kinds of life. The reuse of treated wastewater (TWW) for irrigation is a possibility with challenges to be clarified at scientific level, in particular, its use in irrigation activities due to the eventual contamination of vegetables, like cabbages (Brassica oleracea), by toxic metals and other compounds harmful to humans present in these waters. On the other hand, the use of TWW for vegetable irrigation may allow significant water saving and also providing the cultivated species with nutrients, which may dispense the use of fertilizers. In this work, vegetables such as Brassica oleracea (cabbage), were planted in a greenhouse with a controlled environment (temperature and humidity) located at ISEL campus. Part of the vegetables was irrigated with tap water, and another part with TWW from two wastewater treatment plants (WWTP) located in Lisbon´s District. One of the WWTP receives only domestic wastewater (A), whilst the other one receives industrial and domesti
- Development of a flow injection analytical system for short chain amide determination based on a tubular bioreactor and an ammonium sensorPublication . Veríssimo, M.I.S.; Oliveira, Sara B.; Silva, Nelson A. F.; Matos, Manuel; Karmali, Amin; Gomes, Maria Teresa SRPseudomonas aeruginosa (P. aeruginosa) possesses intracellular amidase activity, which catalyses the hydrolysis of short aliphatic amides producing NH4 +, and has already been used along with an ammonium ion selective electrode for amide quantification. However, the incorporation of a biological membrane turned to be a challenging process and either the final arrangement was prone to amidase losses or the recovery of the sensor coating after the interaction took too long. In this article a flow injection system with an ammonium acoustic wave sensor is proposed, and after testing several different arrangements for the biological element, the ultimate choice consisted of the immobilization of a P. aeruginosa cell-free extract in the inner wall of a tubular glass reactor, which resulted in a reliable analytical system. Response times less than one minute and complete recovery in less than two minutes assured conveniently fast analysis. The analytical system, as long as the column was properly stored in HEPES buffer containing 2 mM β-mercaptoethanol and 1 mM benzamidine and refrigerated when not in use, could be used at least for 20 working days, along a period of one month, maintaining the initial sensitivity.
- A função de auditoria interna numa instituição de ensino superior pública em PortugalPublication . Alexandre, Vítor; Matos, Manuel; Alves, Sílvia de SousaA função de auditoria tem registado uma evolução significativa ao longo do tempo, assumindo uma importância crescente nas Instituições de Ensino Superior Públicas Portuguesas (IESPP). Embora estas instituições beneficiem de uma certa autonomia, estudos recentes revelam variações marcantes na abordagem e atenção dadas à auditoria interna entre as diferentes IESPP. A implementação de um Sistema de Controlo Interno robusto e eficaz, com múltiplos níveis de controlo, é essencial para o bom funcionamento das IESPP. Este sistema é fundamental para prevenir e detetar erros, fenómenos de corrupção e fraudes, bem como mitigar o risco de apropriação indevida de bens e ativos e evitar práticas inadequadas que possam comprometer a gestão eficiente e a reputação das instituições. Nesse contexto, a auditoria interna, frequentemente referida como a 3.ª Linha de Defesa, constitui um dos pilares centrais deste sistema. A relevância da função de auditoria interna nas IESPP é ainda mais evidente considerando o vasto número de intervenientes, tanto internos como externos, que estas instituições envolvem e a vasta quantidade de transações financeiras que estas instituições gerem. A importância das IESPP é sublinhada pelos valores dos seus orçamentos anuais, que em 2024 ascenderão a 2.904 milhões de euros, representando cerca de 0,5% do PIB português, refletindo o seu papel central no desenvolvimento nacional, tanto na investigação quanto na formação de mais de 350 mil estudantes no ano letivo de 2022/2023, segundo dados da DGEEC. Este estudo tem como objetivo caracterizar e evidenciar o papel da função de auditoria interna numa IESPP. Enquanto estrutura de consultoria independente, a auditoria interna é responsável pela avaliação dos processos de gestão e controlo, garantindo a conformidade legal, promovendo o aumento de valor e contribuindo para a melhoria contínua das operações nestas instituições. Contribui ainda para a promoção dos Objetivos de Desenvolvimento Sustentável, ao combater a corrupção e promover uma gestão mais eficaz, responsável e transparente, incentivando a tomada de decisões inclusivas, participativas e representativas.
- Growth of (Perylene)(2) [PD(MNT)(2)] crystalsPublication . Afonso, M. L.; Silva, R. A. L.; Matos, Manuel; Lopes, E. B.; Coutinho, J. T.; Pereira, L. C. J.; Henriques, R. T.; Almeida, M.The conditions for [pd(mnt)(2)]he growth of [pd(mnt)(2)]Perylene) [pd(mnt)(2)] [Pd(mnt) [pd(mnt)(2)]] crystals either by chemical oxidation and electrochemical routes are [pd(mnt)(2)]escribed. The electrocrystallisation is limited by close [pd(mnt)(2)]roximity of [pd(mnt)(2)]he oxidation [pd(mnt)(2)]otentials of [pd(mnt)(2)]he [pd(mnt)(2)]erylene [pd(mnt)(2)]onor and [Pd(mnt) [pd(mnt)(2)]] - anion, and [pd(mnt)(2)]epending on [pd(mnt)(2)]he experimental conditions [pd(mnt)(2)]ifferent [pd(mnt)(2)]orphologies can be obtained. [pd(mnt)(2)]Per) [pd(mnt)(2)] [Pd(mnt) [pd(mnt)(2)]] crystals obtained by elecrocrystallisation were found [pd(mnt)(2)]o be [pd(mnt)(2)]ainly of [pd(mnt)(2)]he β-polymorph with [pd(mnt)(2)]roperties comparable [pd(mnt)(2)]o [pd(mnt)(2)]he Cu, Ni and Pt analogues [pd(mnt)(2)]reviously [pd(mnt)(2)]escribed at variance with [pd(mnt)(2)]hose obtained by chemical oxidation which are [pd(mnt)(2)]ainly of [pd(mnt)(2)]he α-polymorph.
- Heavy metals contamination of urban soils—a decade study in the city of Lisbon, PortugalPublication . Silva, Hugo; Silva, Nelson A. F.; Oliveira, Cristina; Matos, ManuelThere is an intense and continuous growth of the world population living in cities. This increase in population means an increase in car traffic, an increase in new constructions and an increase in the production of waste that translates into an intensive use of land, particularly in terms of soil contaminants. Among other environmental contaminants, toxic metals, such as lead (Pb), cadmium (Cd), nickel (Ni) and chromium (Cr) represent a public health problem. In this study the content of toxic metals in Lisbon’s (Portugal) soils was determined. The study was conducted over approximately a decade in six city locations, with a total of about 700 samples. Each site has different urban characteristics: traffic zone, residential area, urban park and mixed areas. The study allowed to verify the heterogeneity of metal content values in the city soils and their dependence on local traffic. Metal contents were determined by graphite furnace atomic absorption spectroscopy (GFAAS). For each site the geo-accumulation index, pollution factor, degree of contamination, pollution load índex and ecological risk factor were calculated. The mean concentrations of Cd, Cr, Ni and Pb in soils were 0.463, 44.0, 46.6 and 5.73 mg/kg of dry soil, respectively. In the last year of the study the values were 0.417, 51.5, 62.4 and 8.49 mg/kg of dry soil, respectively. Cd and Ni exceeded the typical content values of these metals in the earth’s crust, indicating their anthropogenic origin. The correlation analysis revealed a significant correlation between Cr and Ni, Cd and Ni and Cd and Pb contents in the city soils. Regarding the results obtained in this long monitoring campaign, Lisbon’s soils can be considered as having low levels of pollution by these metals.
- Medidas para poupança de água – abordagens concretas implementadas no ISEL através do projeto de sustentabilidade MySafeWaterPublication . Matos, Manuel; Monge, Nuno; Gonçalves Cavaco Mendes, Mário José; Sousa, Ana Catarina; Silva, Hugo; Costa, Alexandra; Barreiros, Ana MariaO Projeto MySafeWater pretendeu fomentar o uso eficiente da água através de ações concretas para uma melhor gestão dos recursos hídricos numa escola do Ensino Superior, prevenindo a produção de resíduos, diminuído a pegada ecológica. Tendo por base os objetivos, este projeto assentou em três grandes eixos de atuação que serão descritos em detalhe na comunicação a apresentar e resumidamente descritos de seguida.
- OC/EC ratio observations in Europe: Re-thinking the approach for apportionment between primary and secondary organic carbonPublication . Casimiro Pio; Cerqueira, Mario; Harrison, Roy M.; Nunes, Teresa; Mirante, Fátima; Alves, Célia; Oliveira, Cesar; Sanchez de la Campa, Ana; Artinano, Begona; Matos, ManuelThis study explores a large set of OC and EC measurements in PM(10) and PM(2.5) aerosol samples, undertaken with a long term constant analytical methodology, to evaluate the capability of the OC/EC minimum ratio to represent the ratio between the OC and EC aerosol components resulting from fossil fuel combustion (OC(ff)/EC(ff)). The data set covers a wide geographical area in Europe, but with a particular focus upon Portugal, Spain and the United Kingdom, and includes a great variety of sites: urban (background, kerbside and tunnel), industrial, rural and remote. The highest minimum ratios were found in samples from remote and rural sites. Urban background sites have shown spatially and temporally consistent minimum ratios, of around 1.0 for PM(10) and 0.7 for PM(2.5).The consistency of results has suggested that the method could be used as a tool to derive the ratio between OC and EC from fossil fuel combustion and consequently to differentiate OC from primary and secondary sources. To explore this capability, OC and EC measurements were performed in a busy roadway tunnel in central Lisbon. The OC/EC ratio, which reflected the composition of vehicle combustion emissions, was in the range of 03-0.4. Ratios of OC/EC in roadside increment air (roadside minus urban background) in Birmingham, UK also lie within the range 03-0.4. Additional measurements were performed under heavy traffic conditions at two double kerbside sites located in the centre of Lisbon and Madrid. The OC/EC minimum ratios observed at both sites were found to be between those of the tunnel and those of urban background air, suggesting that minimum values commonly obtained for this parameter in open urban atmospheres over-predict the direct emissions of OC(ff) from road transport. Possible reasons for this discrepancy are explored. (C) 2011 Elsevier Ltd. All rights reserved.
- O projeto MySafeWater no ISELPublication . Barreiros, Ana Maria; Silva, Hugo; Matos, Manuel; Gonçalves Cavaco Mendes, Mário José; Monge, Nuno; Sousa, Ana Catarina; Costa, AlexandraO projeto MySafeWater pretendeu promover os objetivos nacionais e europeus, em matéria de Ambiente, no que se refere essencialmente à promoção do “consumo da água da torneira como forma ambientalmente sustentável de consumo, prevenindo a produção de resíduos e diminuindo a pegada ecológica”, através da informação e da conscientização do papel dos cidadãos na promoção do desenvolvimento sustentável em aspetos como a qualidade da água para consumo humano, abrangendo a participação ativa do público e pela sensibilização ambiental e a participação passiva do público.