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2013
Vieira, E. M. F., S. Levichev, C. J. Dias, R. Igreja, M. Buljan, S. Bernstorff, O. Conde, A. Chahboun, A. G. Rolo, and M. J. M. Gomes. "Charge storage behavior of nanostructures based on SiGe nanocrystals embedded in Al2O3 matrix." European Physical Journal B. 86 (2013). AbstractWebsite
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Vieira, Eliana M. F., Sergey Levichev, Carlos J. Dias, Rui Igreja, Maja Buljan, Sigrid Bernstorff, Olinda Conde, Adil Chahboun, Anabela G. Rolo, and Maria J. M. Gomes. "Charge storage behavior of nanostructures based on SiGe nanocrystals embedded in Al2O3 matrix." European Physical Journal B. 86 (2013). Abstract
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Araújo, João, Peter J. Cameron, James D. Mitchell, and Max Neunhöffer. "The classification of normalizing groups." J. Algebra. 373 (2013): 481-490. AbstractWebsite
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Dias, G. F., M. F. S. F. de Moura, J. A. G. Chousal, and J. Xavier. "Cohesive laws of composite bonded joints under mode I loading." Composite Structures. 106 (2013): 646-652. Abstract
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Lajn, A.a, Von Wenckstern Grundmann Wagner Barquinha Fortunato Martins H. a M. a. "Comparative study of transparent rectifying contacts on semiconducting oxide single crystals and amorphous thin films." Journal of Applied Physics. 113 (2013). AbstractWebsite

We demonstrate fully transparent, highly rectifying contacts (TRC) on amorphous GaInZnO and compare them to TRC fabricated on single crystalline bulk ZnO and heteroepitaxial ZnO thin films. The contacts' transparency in the visible spectral range exceeds 70%. From numerical simulations, we conclude that thermionic emission is the dominating transport mechanism, however, for several samples with low net doping density diffusion theory must be applied. The detailed investigation of the rectification properties of the TRC using temperature-dependent current-voltage and capacitance-voltage measurements reveals that barrier inhomogeneities govern the IV-characteristics of all diodes irrespective of the sample crystallinity. Assuming a Gaussian barrier height distribution, the extracted mean barrier heights typically range between 1.1 and 1.3 V. The width of the barrier distribution correlates with the mean barrier height and ranges from 110 to 130 mV. By compiling literature data, we found that this correlation holds also true for Schottky diodes on elemental and III-V semiconductors. © 2013 American Institute of Physics.

Fernandes, A., J. Lousada, J. Morais, J. Xavier, J. Pereira, and P. Melo-Pinto. "Comparison between neural networks and partial least squares for intra-growth ring wood density measurement with hyperspectral imaging." Computers and Electronics in Agriculture. 94 (2013): 71-81. Abstract
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Cerdeira, {Jorge Orestes Lasbarrères}. "Computational comparison of algorithms for a generalization of the node-weighted Steiner tree and forest problems." Livro de Atas do XVI Congresso da Associa{\c c}ão Portuguesa de Investiga{\c c}ão Operacional (IO2013). 2013. 77-87. Abstract

Habitat fragmentation is a serious threat for the sustainability of species. Thus, the identification of effective linkages to connect valuable ecological units is an important issue in conservation biology. The design of effective linkages should take into account that areas which are adequately permeable for some species’ dispersal may act as obstructions for other species. The determination of minimum cost effective linkages is a generalization of both node-weighted Steiner tree and node-weighted Steiner forest problems. We compare the performance of different procedures for this problem using large real and simulated instances.

Teixeira, T., M. Diniz, R. Calado, and R. Rosa. "Coral physiological adaptations to air exposure: Heat shock and oxidative stress responses in Veretillum cynomorium." Journal of Experimental Marine Biology and Ecology. 439 (2013): 35-41. AbstractWebsite
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Vinagre, C., M. Dias, J. Roma, A. Silva, D. Madeira, and M. S. Diniz. "Critical thermal maxima of common rocky intertidal fish and shrimps - A preliminary assessment." Journal of Sea Research. 81 (2013): 10-12. AbstractWebsite
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Martins, R.M., Pereira Siqueira Salomão Freitas S. V. S. "Curcuminoid content and antioxidant activity in spray dried microparticles containing turmeric extract." Food Research International. 50 (2013): 657-663. AbstractWebsite

Curcuma longa L., also known as turmeric, is widely used as a food colorant and has been reported to have antioxidant, anti-inflammatory, anti-mutagenic and anti-cancer properties. The aim of this study was to evaluate the effects of the spray drying on curcuminoid and curcumin contents, antioxidant activity, process yield, the morphology and solubility of the microparticulated solid dispersion containing curcuma extract using a Box Behnken design. The microparticles were spherical in shape, and an increase in outlet temperature from 40 to 80 °C resulted in a significant increase in the yield of microparticles from 16 to 53%. The total curcuminoid content (17.15 to 19.57. mg/g), curcumin content (3.24 to 4.25. mg/g) and antioxidant activity (530.1 to 860.3 μg/mL) were also affected by the spray drying process. The solubility of curcuminoid from C. longa remarkably improved 100-fold in the microparticles, confirming the potential of the ternary solid dispersion technique to improve the dyeing and nutraceutical properties of these compounds. Furthermore, the microparticles were obtained using the spray drying process, can be easily scaled up. © 2011 Elsevier Ltd.

Nandy, S., Gonçalves Pinto Busani Figueiredo Pereira Paiva Martins Fortunato G. J. V. "Current transport mechanism at metal-semiconductor nanoscale interfaces based on ultrahigh density arrays of p-type NiO nano-pillars." Nanoscale. 5 (2013): 11699-11709. AbstractWebsite

The present work focuses on a qualitative analysis of localised I-V characteristics based on the nanostructure morphology of highly dense arrays of p-type NiO nano-pillars (NiO-NPs). Vertically aligned NiO-NPs have been grown on different substrates by using a glancing angle deposition (GLAD) technique. The preferred orientation of as grown NiO-NPs was controlled by the deposition pressure. The NiO-NPs displayed a polar surface with a microscopic dipole moment along the (111) plane (Tasker's type III). Consequently, the crystal plane dependent surface electron accumulation layer and the lattice disorder at the grain boundary interface showed a non-uniform current distribution throughout the sample surface, demonstrated by a conducting AFM technique (c-AFM). The variation in I-V for different points in a single current distribution grain (CD-grain) has been attributed to the variation of Schottky barrier height (SBH) at the metal-semiconductor (M-S) interface. Furthermore, we observed that the strain produced during the NiO-NPs growth can modulate the SBH. Inbound strain acts as an external field to influence the local electric field at the M-S interface causing a variation in SBH with the NPs orientation. This paper shows that vertical arrays of NiO-NPs are potential candidates for nanoscale devices because they have a great impact on the local current transport mechanism due to its nanostructure morphology. © 2013 The Royal Society of Chemistry.

2012
Azevedo, Susana Garrido, and Helena Carvalho. "Contribution of RFID technology to better management of fashion supply chains." International Journal of Retail & Distribution Management. 40 (2012): 128-156. AbstractWebsite

Purpose – The purpose of this paper is to explore the deployment of RFID technology in fashion supply chain management (FSCM). It highlights the contribution of RFID to FSCM, supporting faster logistics activities, with greater products quality, cheaper and with more responsiveness, improving customer satisfaction. Design/methodology/approach – An inductive theory building approach is used to develop a conceptual model for RFID deployment in the {FSCM} context. Secondary data analysis from a sample of six companies supports the identification and discussion of the real advantages, disadvantages and barriers felt by companies in a fashion supply chain when {RFID} technology is introduced. Findings – The logistics activities in the fashion supply chain where {RFID} technology is most widely deployed are: shipping operations, tracking of raw materials, semi-finished components and finished garments, collecting finished goods, handling processes, tracking containers, tracking products from factory to store, receiving operations, monitoring, and sorting of merchandise. In most cases, the tagging operation is performed at some stage in the production process and tag reading occurs at distribution centres or at stores. The main barrier identified to the deployment of {RFID} is the problem of interoperability. The costs associated with the technology are the main disadvantage pointed out by the companies. Practical implications – A conceptual framework is proposed exploring the {RFID} advantages and disadvantages across the fashion supply chain, the main barriers to its introduction and the fashion supply chain logistics activities in which {RFID} could be found. This represents an important contribution to companies in this industry to become more aware of {RFID.} Also, new companies which are thinking of introducing this technology could overcome its barriers easily, improving its advantages and minimizing its disadvantages. Originality/value – This paper explores the deployment of {RFID} in the fashion supply chain from the perspective of technology users.

J. Pacheco, M. Figueiredo, Goes J. "Current-Mode Reference-Shifting Solution for MDAC-based Analog-to-Digital Converters." IEEE International Symposium on Circuits and Systems (ISCAS'2012). Seoul, South Korea: IEEE, 2012.
M., Krippahl, and Grilo A. "Compatibility between design and construction building information models." eWork and eBusiness in Architecture, Engineering and Construction. 2012. 447-452. Abstract
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Cordas, C. M., P. Raleiras, F. Auchere, I. Moura, and JJG Moura. "Comparative electrochemical study of superoxide reductases." European Biophysics Journal with Biophysics Letters. 41.2 (2012): 209-215. AbstractWebsite

Superoxide reductases are involved in relevant biological electron transfer reactions related to protection against oxidative stress caused by reactive oxygen species. The electrochemical features of metalloproteins belonging to the three different classes of enzymes were studied by potentio-dynamic techniques (cyclic and square wave voltammetry): desulfoferrodoxin from Desulfovibrio vulgaris Hildenborough, class I superoxide reductases and neelaredoxin from Desulfovibrio gigas and Treponema pallidum, namely class II and III superoxide reductases, respectively. In addition, a small protein, designated desulforedoxin from D. gigas, which has high homology with the N-terminal domain of class I superoxide reductases, was also investigated. A comparison of the redox potentials and redox behavior of all the proteins is presented, and the results show that SOR center II is thermodynamically more stable than similar centers in different proteins, which may be related to an intramolecular electron transfer function.

Barra, Ana T. P., Fernando F. S. Pinho, and Válter J. G. Lúcio. "Caracterização física e mecânica de argamassas não estruturais, com agregados finos reciclados." 4º Congresso Português de Argamassas e ETICS. Coimbra 2012.
Casimiro, MH, A. G. Silva, JV Pinto, A. M. Ramos, J. Vital, and LM Ferreira. "Catalytic poly(vinyl alcohol) functionalized membranes obtained by gamma irradiation." Radiation Physics and Chemistry. 81.9 (2012): 1314-1318. Abstract
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Lopes, T. C., M. P. Amado, and F. Poggi. "Construção Sustentável – Etapa de Pré-Conceção." 4º Congresso Nacional da Construção 2012. Coimbra: IteCons, 2012. pre_design_final.pdf
Valtchev, {Stanimir Stoyanov}, and {Jorge Joaquim} Pamies-Teixeira. "Culture of the European Student with an Insight to the Future Needs of the Global (European) Labour Market." Proceedings of the European Politechnical University. 1 (2012): 78-82. Abstract

Recent issues of global heating and energy shortages are imposing a need to change our paradigm around transportation. Somehow, electric vehicles are progressively standing as a strong and necessary alternative for the society. Technically and technologically the acceptance of the EV is easier now than ever but the psychology of the consumers and the running business of internal combustion vehicles, the whole existing infrastructure are too much conservative to be changed easily. The changes in technology require changes in the engineering society and its human resources. The objective of this paper is to give a contribution to the discussion and reflection of potential future scenarios where EV/HEV‘s are spread across the society. It gives an overview of the range of knowledge and competences necessary for a sustainable and streamlined development of those. In fact, it is expected that a new kind of professional profiles need to be created or developed to supply the work market with the right human resources. The paper provides some discussion on the creation of new profiles or adaption of existing ones. Among different possible scenarios the creation of post-graduation courses for students holding undergraduate profiles in the fields referred to earlier would be an interesting and viable solution for fast response. The post graduation would be focused in specific key areas of the EV/HEV. Several factors are pointed out to endorse this scenario

Fernandes, Vítor H., and Teresa M. Quinteiro. "The cardinal of various monoids of transformations that preserve a uniform partition." Bulletin of the Malaysian Mathematical Sciences Society. 35.4 (2012): 885-896.
Faísca Phillips, A. M., and A. M. L. Lobo. "Changes in the gender gap in the European Union: the case of women in science, engineering and technology." Women, Science and Globalization, What's Up? Eds. I. Lousada, and M. J. Gonçalves. Lisbon: Minerva, 2012.
Bernardo, M., M. Gonçalves, N. Lapa, R. Barbosa, B. Mendes, and F. Pinto. "Characterization of chars produced in the co-pyrolysis of different wastes: decontamination study." Journal of Hazardous Materials. 207-208 (2012): 28-35. AbstractWebsite

The present work is devoted to the study of the decontamination of chars obtained in the co-pyrolysis of plastics, biomass and tyre wastes. The chars were extracted with several organic solvents of different polarities either individually or in sequence. The ability of each selected extractant to remove toxic pollutants was evaluated by comparing the extraction yields and by characterizing the crude extracts with a combination of chemical analysis and toxicity bioassays. Also, the mineral composition of the treated and non-treated chars was assessed. The results obtained in this study indicate that hexane is the more efficient extraction solvent to be used in the organic decontamination of chars obtained in the co-pyrolysis of plastics, tyres and biomass. A sequential extraction with solvents of increasing polarity can provide a better decontamination of the raw pyrolysis char than any individual extraction. The compounds removed from the char during the decontamination process are mainly aliphatic hydrocarbons and aromatic hydrocarbons, therefore a material that may be upgraded to be used as a fuel and/or as raw material for the organic chemical industry.