Repositório Institucional da Universidade de Aveiro
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Institutionalizing and materializing music through sound sources. The case of Bruce Bastin’s fado collection in Portugal
No full textAs origens da gramaticografia e da lexicologia latino-portuguesas
No full textDoutoramento em LinguísticaApresenta-se neste estudo uma perspectiva ampla da exercitação
metalinguística, da elaboração gramticográfica e lexcográfica,
desde as origens da história da língua portuguesa até aos finais
do século XVI.
A historiografia linguística referente a este período é
essencialmente latino-portuguesa. Este facto não pode deixar de
condiconar o alcance deste estudo, mas não invalida e seu
interesse mesmo sob o ponto de vista da história da língua
portuguesa,que é a área em que pretende situar-se mais
especificamente este trabalho.
Vai compor-se no seu conjunto de quatro partes , assim
distribuídas: I - gramaticografia; II - lexicografia medieval; III -
lexicografia do Renascimento; IV - pré-lexicografia portuguesa
A física e a química do C60
No full textMestrado em Ensino de Física e QuímicaCom a descoberta dos fullerenos e sobretudo, com a
capacidade de sintetizá-los em grandes quantidades,
nasce uma nova forma alotrópica do carbono cuja unidade
estrutural mais abundante é a molécula de C60. A extrema
estabilidade desta molécula é explicada pela elevada
simetria da sua estrutura em forma de um icosaedro
truncado. No estudo das propriedades físicas e químicas
de substâncias elementares constituídas pelo mesmo
elemento o exemplo do diamante e da grafite é já,
tradicionalmente, utilizado e referenciado. É, sem
dúvida, surpreendente e interpelativo o facto destes
dois alótropos possuírem propriedades físicas tão
contraditórias: a dureza, o brilho e a transparência do
diamante contrapõem-se à moleza, à cor negra e à
opacidade da grafite. A chegada da terceira forma
alotrópica do carbono suscita uma enorme curiosidade em
torno das propriedades dos cristais moleculares de C60 e
da molécula em si, levando a uma inevitavelmente
comparação com as propriedades e estrutura elementar dos
outros alótropos do elemento carbono.
O estudo desenvolvido teve como principal objectivo
verificar se a substancia elementar C60 é passível de ser
estudada em níveis de escolaridade não universitários.
Neste sentido, desenvolveu-se um estudo teórico sobre as
propriedades físicas e químicas que os cristais de C60
manifestam, nomeadamente, a sua supercondutividade e a
reactividade química, as quais são realçadas pela
importância das suas possíveis aplicações. Foi também
realizado um estudo empírico comparativo das
propriedades físicas dos cristais e de filmes de cada
uma das três substâncias elementares de carbono, tendo
sido utilizadas as instalações e o equipamento do
Departamento de Física da Universidade de Aveiro, no ano
lectivo 2000/2001.
Os resultados obtidos permitiram concluir que é possível
verificar nos níveis de ensino Básico e Secundário, as
diferentes características que uma substância elementar
pode assumir, nomeadamente, a morfologia e orientação
dos cristais.
O Estudo tem como primeiros destinatários professores de
Física e Química (ensinos Básicos e Secundário) e
considera-se que este estudo pode servir de base de
trabalho para aqueles que pretendam fornecer aos seus
alunos, como actividade de enriquecimento científico, e
por isso mesmo cultural, noções fundamentais e actuais
da Física e da Química.With the discovery of fullerens and mainly, with the
capacity of
producing them in big quantities, a new allotropic form
of carbon is born, in which the mostly abundant
structural unit
is the C60 molecule. The high stability of this molecule
can be
explained by the symmetry of its structure with the
shape of a truncated icosahedron. In the study of
physical and chemical properties of elementary
substances formed by the same element, diamond and
graphite are the most referred and traditionally given
examples. The fact that these two allotropes have such
contradictory physical properties: the hardness, the
brightress and the transparency of diamond as oppose to
the softness, to the black colour and to the opacity of
graphite is undoubtedly amazing and interpellant. The
arrival of the third allotropic form of carbon arises
enormous curiosity around the properties of C60 molecular
crystals and abount the molecule itself, leading to an
inevitable comparison with the properties and elementary
structure of other allotropes of the carbon element.
The main aim of this study was to check if the
elementary substance C60 can be studied in different nonuniversity
school levels. Therefore, a theoretical study
on the physical and chemical properties that C60 crystals
presents, particularly its superconductivity and
chemical reactivity which are highlighted by the
importance of its possible applications, was conducted.
Also an empirical study took place to compare the
physical properties of crystals and films of each of the
three elementary substances of carbon. This was done
with the use of equipment from the Physics Department at
the University of Aveiro, during the school year of
2000/2001.
The results obtained lead to the conclusion that, it is
possible in Elementary and Secondary school levels, to
check the different characteristics which an elementary
substance may assume, mainly the morphology and the
orientation of the crystals. The study was oriented to
Elementary and Secondary Physics and Chemistry School
teachers, and it is believed that this study may be a
basis of work for those who want to give their students
fundamental and up-to-date notions of Physics and
Chemistry, as an activity of scientific, and therefore,
cultural enrichment
Life cycle assessment of broiler chicken production: a portuguese case study
No full textAn environmental assessment of the life cycle of broiler chicken production from a cradle-to-slaughterhouse gate perspective was carried out with the aim of identifying the environmental hotspots of the system. To do so, broiler chicken production in Portugal was investigated in detail. Inventory data for the different production stages (chicken farm- and slaughterhouse-related activities) was gathered in collaboration with an integrated Portuguese chicken company. Results showed that the chicken farm is the main factor responsible for the environmental impacts analysed. Specifically, both feed production and on-farm emissions were the main environmental hotspots. Concerning the slaughterhouse-related activities, the production of electricity and packaging materials presented a significant contribution at this stage. The environmental results were compared with other published Life Cycle Assessment studies of chicken production in other countries, with special attention paid to the quantification of greenhouse gas emissions. A number of improvement actions are proposed to reduce the environmental impacts of poultry litter management and feed production. Moreover, studies of pork, beef and fish (sardines) were also included for comparison using a functional unit based on an identical protein content. The results (excluding subsequent packaging) showed that the production of broiler chicken could be preferable in comparison to other types of meat due to its lower global warming potential. On the contrary, sardines presented a reduction of 88% in comparison with the chicken profile; however, the availability of sardines for consumption may be limited throughout the year due to EU fishing protocols concerning sea stocks protection
Assessing the socio-economic impacts of green/blue space, urban residential and road infrastructure projects in the Confluence (Lyon): a hedonic pricing simulation approach
No full textUrban green/blue spaces are put under pressure as urban areas grow, develop and evolve. It is increasingly recognized, however, that green/blue spaces provide important ecosystem services, stimulate higher real estate prices and prevent flooding problems. This paper aims to assess and compare the socio-economic impacts of potential green/blue space, urban residential and road infrastructure development scenarios in the Lyon Confluence project area (France), using the Sustainable Urbanizing Landscape Development (SULD) hedonic pricing simulation model. Results show four major tendencies regarding the value-added of green/blue spaces in urban landscapes: (1) cities become more compact; (2) population densities increase; (3) real estate values rise; and (4) demographic distribution patterns change. The magnitude of these impacts depends, however, on the quality and size of the intervention, the social classes attracted to the intervention area and on the location of the intervention relative to existing residential areas, urban centres, road infrastructure and environmental amenities
Investigating Landfill Contamination by Visualizing Geophysical Data
No full textGeophysical experts aimed to establish a method to identify contamination by landfill leakage without chemically analyzing subsoil samples, which is time-consuming and expensive. To that end, researchers developed a software package that let the experts create 3D visualizations of geophysical data acquired around the landfill and apply statistical analysis to detect anomalous values. The data used, electrical resistivity, are typically sparse. So, the application employs kriging to interpolate the data and provide a volumetric representation of the subsoil resistivity. To avoid invalid conclusions, the visualization also represents uncertainty. The application enabled the experts to better understand the phenomenon and to develop and validate their method. Their evaluation of the application indicated that it helped them throughout the method's development and significantly eased their workload
Estudos da cortiça do Quercus suber L.. Indicadores de interacção em sistemas cortiça/soluções modelo de vinho
No full textMestrado em Química dos Produtos Naturais e AlimentosA cortiça, como produto natural, é susceptível de sofrer contaminações que poderão
alterar as propriedades físico-químicas que condicionam a sua utilização pela indústria
para a produção de rolhas. Uma contaminação que poderá ocorrer na cortiça é a
“Mancha Amarela” que provoca nas rolhas uma descoloração e um cheiro a mofo/bolor.
Este defeito tem sido associado frequentemente ao ataque da Armillaria mellea à
cortiça no montado.
Este defeito pode influenciar negativamente as características do vinho quando em
contacto com este tipo de cortiça.
Os objectivos deste trabalho são: i) efectuar um estudo da cortiça proveniente de um
montado contaminado com Armillaria mellea e a possível relação entre a Armillaria
mellea e o defeito “Mancha Amarela”; ii) procurar metodologias que forneçam perfis
globais que permitam detectar no vinho o contacto com cortiça boa e com “Mancha
Amarela”.
Este trabalho encontra-se dividido em três grandes partes: na primeira faz-se uma
introdução teórica ao assuntos a estudar, na segunda são apresentados os materiais e
métodos utilizados e na última são apresentados os resultados obtidos.
Durante este estudo procedeu-se ao acompanhamento da cortiça desde que foi
extraída do sobreiro na forma de pranchas até ser industrialmente transformada em
discos de cortiça a usar na produção de rolhas para espumante. Foram assim
realizados estudos espectroscópicos recorrendo a: Ressonância Magnética Nuclear
(NMR), Infravermelho com Transformadas de Fourier (FTIR) e Fluorescência. Esta
metodologia fornece impressões digitais espectroscópicas que reflectem a composição
química da amostra em estudo. A análise integrada dos diferentes perfis
espectroscópicos recorrendo à Análise Multivariada (Análise em Componentes
Principais) fornece informação sobre a interacção cortiça/soluções modelo de vinho e
permite analisar a sua variabilidade, agrupando-as consoante as diferenças e
semelhanças espectroscópicas. Esta abordagem pode funcionar como técnica de
rastreio para identificar o tipo de cortiça que esteve em contacto com o vinho. Para
complementar estes estudos foram realizadas observações recorrendo à Microscopia
Electrónica de Varrimento (SEM) e foi estudada a presença de 2,4,6-tricloroanisol por
SPME-GC-MS.As a natural product, cork extracted from Quercus suber L., can suffer contaminations
that can change its proprieties. The study of its proprieties gives us some signs of its
chemical and physical condition that will decide on the use it will have in industry. One
common contamination is the so called “yellow spot”, witch provoke in cork stoppers a
discoloration and a mouldy smell. This defect is usually associated to the presence in
the tree of the fungi Armillaria mellea.
The objective of this work is to: i) study cork from a contaminated field with Armillaria
mellea; ii) develop a methodology that indicates, in wine models and wine, the presence
of compounds derived from contact with good cork and cork contaminated with “yellow
spot”.
This work is divided in three parts: in the first one the theory of the subjects to study is
presented, on the second the materials and methods used are described and on the
last, the results are shown and discussed.
The work here presented followed cork from harvest as cork boards to its industrial
transformation in cork disks to be used in sparkling cork stoppers. To perform this study
different spectroscopic techniques were used: Nuclear Magnetic Resonance (NMR),
Fourier Transform Infra Red (FTIR) and Fluorescence. This methodological approach
will provide spectroscopic fingerprints that characterize the chemical composition of the
samples in study. The jointly analysis of the different spectroscopic profiles, using
Principal Component Analysis, provides information concerning the interaction
cork/wine model solutions, its variability grouping the different samples based on the
spectroscopic differences. This methodology can then be used to detect the kind of cork
that has been in contact with a wine. To complement these studies, Scanning Electronic
Microscopy (SEM) and the detection of 2,4,6- trichloroanisol by SPME-GC-MS were
also performed on the samples studied
The promise and challenges of visible light communication.
No full textLight-emitting diodes (LEDs) are becoming
increasingly ubiquitous. They can be found
in illumination appliances, phones, TVs,
advertising panels, dashboards, and
traffic signals, among others. Most
illumination applications are becoming
LED based, mainly due to their long
operational lifetime and high energy
efficiency, which is nowadays higher
than 100 lm/W [1]. Other benefits
include enhanced sustainability,
a compact form factor, easier
maintenance, and lower cost. For
these reasons, LED lighting is
expected to have a market share of
84% in the general illumination
market by 2030 [2]. However,
there is another characteristic that
is not being fully exploited: LEDs
are capable of switching their light
intensity at a rate that is imperceptible
to the human eye. This property
has been used for dimming purposes
but can also be utilized in the opportunistic
deployment of value-added services
based on visible light communication (VLC)
Oral bioaccessibility and human exposure to anthropogenic and geogenic mercury in urban, industrial and mining areas
No full textThe objective of this study was to characterize the link between bioaccessibility and fractionation of mercury (Hg) in soils and to provide insight into human exposure to Hg due to inhalation of airborne soil particles and hand-to-mouth ingestion of Hg-bearing soil. Mercury in soils from mining, urban and industrial areas was fractionated in organometallic forms; mobile; semi-mobile; and non-mobile forms as well as HCl-extractable Hg. The in vitro bioaccessibility of Hg was obtained by extracting soils with (1) a simulated human gastric fluid (pH1.5), and (2) a simulated human lung fluid (pH7.4). Total soil Hg concentrations ranged from 0.72 to 1.8mgkg-1 (urban areas), 0.28 to 94mgkg-1 (industrial area) and 0.92 to 37mgkg-1 (mining areas). Both organometallic Hg as well as 0.1M HCl extractable Hg were lower (<0.5% of total Hg) than Hg extracted by gastric fluid (up to 1.8% of total Hg) and lung fluid (up to 12% of total Hg). In addition, Hg extracted by lung fluid was significantly higher in urban and industrial soils (average 5.0-6.6% of total Hg) compared to mining soils. Such differences were related to levels of mobile Hg species in urban and industrial soils compared to mining soils. These results strengthen the need to measure site-specific Hg fractionation when determining Hg bioaccessibility. Results also show that ingestion and/or inhalation of Hg from soil particles can contribute up to 8% of adult total Hg intake when compared to total Hg intake via consumption of contaminated fish and animal products from contaminated areas
Ocean cleaning stations under a changing climate: biological responses of tropical and temperate fish-cleaner shrimp to global warming
No full textCleaning symbioses play an important role in the health of certain coastal marine communities. These interspecific associations often occur at specific sites (cleaning stations) where a cleaner organism (commonly a fish or shrimp) removes ectoparasites/damaged tissue from a 'client' (a larger cooperating fish). At present, the potential impact of climate change on the fitness of cleaner organisms remains unknown. This study investigated the physiological and biochemical responses of tropical (Lysmata amboinensis) and temperate (L. seticaudata) cleaner shrimp to global warming. Specifically, thermal limits (CTMax), metabolic rates, thermal sensitivity, heat shock response (HSR), lipid peroxidation [malondialdehyde (MDA) concentration], lactate levels, antioxidant (GST, SOD and catalase) and digestive enzyme activities (trypsin and alkaline phosphatase) at current and warming (+3 °C) temperature conditions. In contrast to the temperate species, CTMax values decreased significantly from current (24-27 °C) to warming temperature conditions (30 °C) for the tropical shrimp, where metabolic thermal sensitivity was affected and the HSR was significantly reduced. MDA levels in tropical shrimp increased dramatically, indicating extreme cellular lipid peroxidation, which was not observed in the temperate shrimp. Lactate levels, GST and SOD activities were significantly enhanced within the muscle tissue of the tropical species. Digestive enzyme activities in the hepatopancreas of both species were significantly decreased by warmer temperatures. Our data suggest that the tropical cleaner shrimp will be more vulnerable to global warming than the temperate Lysmata seticaudata; the latter evolved in a relatively unstable environment with seasonal thermal variations that may have conferred greater adaptive plasticity. Thus, tropical cleaning symbioses may be challenged at a greater degree by warming-related anthropogenic forcing, with potential cascading effects on the health and structuring of tropical coastal communities (e.g. coral reefs)