IPT - OAI - Artigos em Revistas Científicas
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- Achievements of the journal in 2017 | Sucessos de uma revista em 2017Publication . Cruz, António João; Figueira, Francisca; Revez, Maria João
- An insight into the surface properties of calcined kaolinitic clays: The grinding effectPublication . Gamelas, José; Ferraz, Eduardo; Rocha, FernandoThe present work aimed characterizing in a systematic way the surface of metakaolinitic materials produced by calcination of a kaolinitic clay at different temperatures and to study the effect of grinding on the surface properties of metakaolinitic materials. Using X-ray photoelectron spectroscopy, it was found for all materials a Si/Al atomic ratio close to 1, confirming the presence of the 1:1 clay structure. By inverse gas chromatography, an increase of the Lewis basic properties of the surfaces of metakaolinitic materials in comparison to the original clay was found, which was due to the condensation of hydroxyl groups in the structure of the clay. The grinding of the metakaolinitic materials afforded a decrease of the dispersive component of the surface energy () as well as an increase of the specific interaction with sterically hindered molecules, caused by the diminishing of the materials surface nanoroughness. The Lewis basic properties of the materials surface also increased with grinding. Noticeably, for all studied materials a good inverse relation could be found between the and the specific interaction of trichloromethane (but not with dichloromethane), showing the importance of surface nanoroughness on the adsorption process of bulky molecules.
- Análise dos projetos e das obras no Palácio Foz, em Lisboa, entre 1887 e 1904: contributo para a sua reconstituição arquitetónica e construtivaPublication . Moreira, Anabela Mendes; Serrano, InêsA caracterização arquitetónica e construtiva de um edifício é fundamental em qualquer processo de intervenção. A proficiência desses processos depende, em grande medida, do conhecimento profundo do edifício e da correta interpretação das alterações que nele se tenham operado. A reconstituição construtiva, sobretudo de edifícios mais antigos e que foram submetidos a maior número de intervenções no decurso do tempo, nem sempre é possível, dada a inexistência ou a insuficiência de registos escritos do seu projeto inicial, ou das suas sucessivas alterações. Existem, porém, exceções que se referem principalmente a edifícios com maior notabilidade, onde é possível revisitar o processo projetual, através de registos coevos, e, no caso de obras mais recentes, identificar e analisar os estratos referentes às várias intervenções, através da análise documental geralmente depositada em arquivos institucionais. Neste artigo procede-se à possível reconstituição arquitetónica e construtiva dos elementos do envelope (cobertura e paredes exteriores) de um dos edifícios mais distintos da cidade de Lisboa, o Palácio Foz, erigido na sequência do terramoto de 1755. O trabalho de pesquisa realizado focou-se na análise dos requerimentos submetidos pelo Marquês da Foz à Câmara Municipal de Lisboa no período compreendido entre 1887 e 1904. Os referidos requerimentos correspondem a pedidos escritos de alterações, ampliações e renovações construtivas solicitados pelo proprietário. Este estudo pretende identificar e datar as principais alterações arquitetónicas e construtivas realizadas no envelope do edifício, relativamente à construção inicial, enquadrando-as com as alterações urbanísticas da zona envolvente. Pretende-se, assim, contribuir para a caracterização da história arquitetónica e construtiva do edifício, explicitando a relação entre as práticas construtivas e o contexto urbano durante aquele período.
- Annunciation or Adoration? The workshop practice and the hesitations of a Portuguese mannerist painter revealed by infrared reflectographyPublication . Melo, Helena P.; Cruz, António João; Valadas, Sara; Candeias, AntónioThe examination with infrared reflectography of the Annunciation and the Adoration of the Shepherds, two panels from a dismembered altarpiece attributed to the mannerist painter Francisco João (doc. 1558–1595), revealed the first documented example in Portuguese painting of the overlapping of two underdrawing layouts, each with a different subject, in a single panel painting. The paintings were examined under visible radiation and infrared reflectography was used to investigate the underdrawing in terms of the materials, graphic layout and function. Results from a previous study on the ground layers and underdrawing materials of these paintings, obtained with the analysis of micro-samples with microscopic and spectroscopic techniques, were used in the context of this research. Infrared images revealed that the underdrawing of the Annunciation mostly corresponded to the painted image but that two subjects — Annunciation and Adoration — were drawn over the prepared surface of the panel depicting the Adoration. This discovery is the first example of this procedure in Portuguese painting. The comparison with a third panel attributed to the painter, depicting another version of the Annunciation, allowed for the discussion of relevant technical procedures such as the use of cartoons, the responsibility for each main stage of painting creation and the reality of labour conditions in a regional market. The results contributed with material evidence to the scarce information of archival nature about the working methods of Portuguese mannerist painters.
- Biblioteca Digital Ciarte: literatura histórica técnico-artística em portuguêsPublication . Cruz, António JoãoThe Ciarte Digital Library (http://biblioteca.ciarte.pt), recently created, has as objectives, on the one hand, to give access to the ancient technical and artistic literature in Portuguese through volumes in pdf format resulting from purposely carried out digital restoration and, on the other hand, to make available information about these fundamental sources both for the knowledge of ideas, techniques and materials from which works of art and other cultural assets are made, and for the interpretation of the data obtained through different methodologies of the Humanities or Sciences. The presentation made here, in addition to the Library's promotion for those interested in these sources that are difficult to access, also intends to expose the principles underlying it and the technical options taken, which may be useful for similar projects. The close and prolonged contact with the great diversity of works already digitised serves as a support for the proposed typological classification of this literature.
- Bridging Culture, Tourism, and Literature: The Short Videos of Saramago's Small Memories of AzinhagaPublication . Silva, Julio; Santos, Luis; Silva, Manuela; Cordeiro, João; Carmo, Ana do; Romana, Maria Barras; Caetano Domingos, Susana IsabelA arte, conforme definida por Leo Tolstoi (2013), é a atividade pela qual uma pessoa, tendo experimentado uma emoção, transmite-a intencionalmente a outros. A forte ligação entre o enquadramento geográfico e experiências do autor, despoleta a imaginação do leitor e a vontade de viver na primeira pessoa as experiências. Algumas obras literárias e autores que estimularam os leitores a viajar, por exemplo Stratford-upon-Avon, de William Shakespeare, contribuem para o desenvolvimento local. Outros artistas e formas de arte também exercem o mesmo efeito, César Manrique em Lanzarote com pinturas, esculturas e arquitetura, ou o livro de John Ronald Reuel Tolkien através do filme Senhor dos Anéis promovendo a Nova Zelândia. Turismo cinematográfico ou turismo induzido por filmes é definido como qualquer viagem motivada por cenário com o objetivo de visitação. Nem todos os turistas cinematográficos são motivados da mesma forma, alguns são motivados por cenário, circunscrito e específico, enquanto generalistas visitam regiões ou países (Gürkaya, 2010). O estudo atual visa desenvolver 8 curtas-metragens da obra literária As Pequenas Memórias (2006) do Prémio Nobel José Saramago, onde o autor descreve o seu local de nascimento e experiências da juventude. Este trabalho mais do que a expressão de arte audiovisual visa promover o turismo cultural através uma de ampla estratégia integrada de turismo regional. O potencial deste turismo para o desenvolvimento ainda não atingiu a maturidade. Todos os tipos de turismo são efémeros, assim como os filmes, pelo que qualquer estratégia desenhada que contempla tais soluções necessita de uma reinvenção regular a fim de garantir a sua sustentabilidade.
- Caracterização através de análise química da escultura portuguesa sobre madeira de produção erudita e de produção popular da época barrocaPublication . Barata, Carolina; Carballo, Jorgelina; Cruz, António João; Coroado, João; Araújo, Maria Eduarda; Mendonça, Maria HelenaMaking use of several analytical techniques, four erudite and four popular Portuguese baroque wooden sculptures were studied. The materials and techniques employed were identified and the relationship between their artistic quality and the materials used was investigated. In general, the pigments were common at the time, but one pigment discovered in the beginning of the 18th century and two rare arsenic pigments were also identified. In popular sculptures cost-saving was detected, particularly concerning the gold leaf. Regarding some technical procedures identified, recommendations found in historical documents did not seem to have been entirely followed, neither in erudite nor in popular sculptures.
- Charcoal or black stone? Reconstructions as a tool to study the behaviour of dry underdrawing materials within the paint structure of sixteenth century panel paintingsPublication . Melo, H.P.; Valadas, Sara; Cruz, António João; Candeias, AntónioReconstructions were used as a tool to investigate the use of charcoal and black stone as underdrawing materials in sixteenth century panel paintings with white or off-white preparatory layers. Research was based on the examination of a group of sixteenth century panel paintings by the Portuguese Mannerist painter Francisco João (doc. 1558–1595) and his workshop. Analysis of the original underdrawing material in cross-sections, using microscopic and spectroscopic techniques was not always conclusive. Based on materials thought to be employed by Francisco João and on data collected from sixteenth and seventeenth century European technical treatises along with published analytical studies of panel paintings with white or off-white preparatory layers from this period, reconstructions were performed using charcoal (untreated and oiled—as described in contemporary literature) and natural black stone over different preparatory surfaces. Microscopic analyses of cross-sections from reconstructions were made to assist the discussion of the behaviour of the dry underdrawing media within the paint structure. Results revealed that whereas charcoal could be easily removed if drawn directly over gesso, it would remain fixed when drawn over a ground treated with an oil-based intermediate layer, even when the latter was completely dry to the touch. The persistence of a charcoal drawing when applied over oil challenged the widely disseminated assumption that naturally occurring black stone, which makes a permanent mark, had been employed more frequently than charcoal since the latter appeared to be easily disturbed and hence transitory. The very lengthy curing time for a drying oil could be responsible for fixing the friable media. Reconstructions further showed that oiled charcoal is easily prepared and agreeable to use on any type of surface, where it remains without smudging. Finally, research suggests that the painter’s choice of underdrawing material is closely dependent on the nature of the binder of intermediate layers and on the position of the underdrawing layout within the paint structure.
- Clays from Vila Nova da Rainha (Portugal): Appraisal of their relevant properties in order to be used in construction ceramicsPublication . Coroado, João; Ferraz, Eduardo; Gomes, Celso F.; Rocha, FernandoThe clay deposit of Vila Nova da Rainha (VNR) is included in the lithostratigraphic forma tion named “Argilas de Tomar”, and is located at the lower section of the Tert iary Tagus’ river basin. Clay from one quarry is being extracted for the production of construction ceramics. In this work the firing transformations undergone by VNR cl ays containing quartz, alkaline feldspar, iron oxy-hydroxides, and clay minerals have been studied. Ca rbonates have not been identified in thes e raw materials. The clay layers can be subdivided in three groups based upon composition and ceramic properties. The first group, VNR0, is represented by smectite-kaolinite sandy-silty clay, the second group (VNR1 and VNR2) corresponds to illite-kaolinite bearing clay and the third group (VNR3 and VNR4) is represented by illite-smectite silty clay. The firing process involves the formation of hematite and mu llite both influencing the technical properties of the fired products. With regards to the ceramic properties assessed at 1100 ºC the first group showed the lowest total shrinkage value (7.35 %) the highest water absorption value (12.2 %) and the lo west mechanical bending strength value (12.0 MPa); the same properties assessed in the second group provi ded the highest firing shrinkage values (7.0-5.0 %), the lowest values of water absorption (0.1-0.2 %) and relatively high mechanical bending strength values (47.8-48.0 MPa); the third group showed firing shrinkage values within the range 3.5-4.2 %, water absorption values within the range 1.4-4.5 %, and the highest mechanical bending strength values (49.2-52.0 MPa). The results of the ceramic properties being appraised indicate that the raw materials being studied are suitable for the production of high-quality construction ceramics, such as brick, roof tile and rustic floor tile.
- Como Garantir o Controlo Interno Através de Sistemas de Informação: Uma Abordagem TeóricaPublication . Miguel, Silvia; Marques, C. G.; Oliveira, DanielO controlo interno é um processo de grande importância para as organizações. Consiste num conjunto de políticas e procedimentos e é desenvolvido para garantir a fiabilidade e a segurança a todas as partes interessadas. Neste sentido, torna-se crucial que as organizações tenham sistemas informáticos que auxiliem os gestores nas suas tomadas de decisão, garantindo que a informação apresentada é confiável. Assim, o presente artigo pretende analisar sistemas de informação que apoiem no controlo interno das organizações. Para o estudo, foi realizada uma especificação de requisitos utilizando como técnica de recolha de dados, o inquérito e como instrumento de recolha de dados o guião de entrevista. Para a identificação das ferramentas existentes no mercado e analisar se cumpriam com os requisitos, recorreu-se à técnica análise documental e ao instrumento de recolha de dados grelha estruturada. Verificou-se com base na análise realizada que atualmente não existe nenhum sistema de informação que consiga mitigar os requisitos identificados. Para trabalho futuro, seria interessante proceder-se ao desenvolvimento e implementação de um sistema de informação de apoio ao controlo interno das organizações.