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2008
Rita, F., O. Mateus, and M. Overbeeke. "Tomografia Computorizada na Deteccão de Fraudes em Fósseis." Acta Radiológica Portuguesa. 80 (2008): 83-84. Abstractrita_et_al_2008_tomografia_computorizada_na_deteccao_de_fraudes_em_fosseis.pdfWebsite

The material in analysis is the skull of an Ornitiquous Psittacosaurus of the China Cretaceous suspicious of being a fraud. The fossil described here appeared to be in very good condition and conservation. The skull is almost complete but because it is filled by sediment, this prevents an analyse of the intra-skull anatomy.
With the intuition of confirming or not the existence of fossiled bone elements in the interior of the sedimented mass that filled the Psittacossaurus skull, it was submitted to a Computorized Tomography.
The Psittacosaurus skull showed an unexpected absorption of the x-rays, because of the outstanding differences of density between the bone and the matrix due to the fact that the interior of the skull was composed by an amalgam of materials, where a less compact and relatively homogeneous material (soil and wax) was found and that material united and mounted the whole skull and the normal bone structures were non-existing.
The capacity of the Computorized Axial Tomography of differentiating materials with different densities of absorption of x-rays, permitted an easy and reliable investigation and explained beyond doubt the quality of the fossil specimen studied, concluding with no doubt that in spite of the realistic aspect, we had come before a fraud.

B. Barroca, Vasco Amaral, M. Risoldi, M. Caprini, A. Moreira, and J. Araújo. "Towards the Application of Model Based Design Methodology for Reliable Control Systems on HEP Experiments." 11th IEEE Nuclear Science Symposium, Proceedings. IEEE, 2008. Abstract

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M. Alferez, U. Kulesza, A. Moreira, J. Araújo, and Vasco Amaral. "Tracing between Features and Use Cases: A Model-Driven Approach." Proceedings of the Second International Workshop on Variability Modelling of Software Intensive Systems. Ed. Andreas Metzger Klauss Pohl Patrick Heymans, Kyo-Chul Kang. ISBN 1860-2770. 2008. 81-88. Abstract

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Mateus, O. "Two ornithischian dinosaurs renamed: Microceratops Bohlin 1953 and Diceratops Lull 1905." Journal of Paleontology. 82 (2008): 423. Abstractmateus_2008_two_ornithischians_renamed__microceratops_bohlin_1953_and_diceratops_lull_.pdfWebsite

dinosaur genera Diceratops Lull, 1905 and Microceratops Bohlin, 1953 are preoccupied by the Hymenoptera insects, Diceratops Foerster, 1868 and Microceratops Seyrig, 1952, respectively. Therefore, the name of the ceratopsian dinosaur Diceratops Lull, 1905 from the Late Cretaceous of United States is a junior homonym of the hymenoptera Diceratops Foerster, 1868. Diceratus n. gen. (Greek di ‘‘two,’’ Greek ceratos ‘‘horned’’) is proposed as the replacement name of Diceratops Lull, 1905. Some workers have considered Diceratops synonymous with Triceratops (e.g., Dodson and Currie, 1990) but it was reinstated by Forster (1996) after analysis of the characteristics of all existing ceratopsid skulls, and recent reviews (e.g., Dodson et al., 2004) have considered Diceratops a valid genus.
Due to preoccupation, the name of the ceratopsian dinosaur Microceratops Bohlin, 1953 from the Cretaceous of the Gobi is
a junior homonym of the insect Microceratops Seyrig, 1952. Microceratus n. gen. (Greek micro ‘‘small,’’ Greek ceratos ‘‘horned’’) is proposed as the replacing name of Microceratops Bohlin, 1953.
Sereno (2000:489) has declared Microceratops a nomen dubium since the holotype material lacks any diagnostic features, a
convention followed by You and Dodson (2004:480). However, the name is still used by Le Loeuff et al. (2002), Lucas (2006),
Alifanov (2003) and Xu et al. (2002), and such practice justifies the renaming of the genus.
In order to preserve some stability, the names chosen here deliberately preserve the same prefixes.

Malan, AG, JP Meyer, PJ Coelho, and D. Aelenei. "Application of high-order spatial resolution schemes to the hybrid finite volume/finite element method for radiative transfer in participating media." International Journal of Numerical Methods for Heat & Fluid Flow. 18 (2008): 173-184. AbstractWebsite

Purpose ? This paper sets out to implement bounded high?order (HO) resolution schemes in a hybrid finite volume/finite element method for the solution of the radiative transfer equation. Design/methodology/approach ? The hybrid finite volume/finite element method had formerly been developed using the step scheme, which is only first?order accurate, for the spatial discretization. Here, several bounded HO resolution schemes, namely the MINMOD, CLAM, MUSCL and SMART schemes, formulated using the normalized variable diagram, were implemented using the deferred correction procedure. Findings ? The results obtained reveal an interaction between spatial and angular discretization errors, and show that the HO resolution schemes yield improved accuracy over the step scheme if the angular discretization error is small. Research limitations/implications ? Although the HO resolution schemes reduce the spatial discretization error, they do not influence the angular discretization error. Therefore, the global error is only reduced if the angular discretization error is also small. Practical implications ? The use of HO resolution schemes is only effective if the angular refinement yields low?angular discretization errors. Moreover, spatial and angular refinement should be carried out simultaneously. Originality/value ? The paper extends a methodology formerly developed in computational fluid dynamics, and aimed at the improvement of the solution accuracy, to the hybrid finite volume/finite element method for the solution of the radiative transfer equation.

Mateus, O., G. Dyke, N. Motchurova-Dekova, P. Ivanov, and GD Kamenov. "The Bulgarian dinosaur: did it exist? European late Cretaceous ornithomimosaurs." 56th Symposium of Vertebrate Palaeontology and Comparative Anatomy. Dublin 2008. 47. Abstract
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Mateus, O., G. Dyke, N. Motchurova-Dekova, P. Ivanov, and GD Kamenov. "The Bulgarian dinosaur: did it exist? European late Cretaceous ornithomimosaurs." 56th Symposium of Vertebrate Palaeontology and Comparative Anatomy. Dublin 2008. 47. Abstract
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Monteiro, R. C. C. a, C. F. a Figueiredo, M. S. a Alendouro, M. C. b Ferro, E. J. R. b Davim, and M. H. V. b Fernandes. "Characterization of MSWI bottom ashes towards utilization as glass raw material." Waste Management. 28 (2008): 1119-1125. AbstractWebsite

The characterization of the bottom ashes produced by two Portuguese municipal solid waste incinerators (MSWI) was performed with the aim of assessing the feasibility of using this waste as raw material in the production of glass that can be further processed as glass-ceramics for application in construction. Density and particle size distribution measurements were carried out for physical characterization. Chemical characterization revealed that SiO2, a network glass former oxide, was present in a relatively high content (52-58 wt%), indicating the suitability for this waste to be employed in the development of vitreous materials. CaO, Na2O and K2O, which act as fluxing agents, were present in various amounts (2-17 wt%) together with several other oxides normally present in ceramic and glass raw materials. Mineralogical characterization revealed that the main crystalline phases were quartz (SiO2) and calcite (CaCO3) and that minor amounts of different alkaline and alkaline-earth aluminosilicate phases were also present. Thermal characterization showed that the decomposition of the different compounds occurred up to 1100 °C and that total weight loss was <10 wt%. Heating both bottom ashes at 1400 °C for 2 h resulted in a melt with suitable viscosity to be poured into a mould, and homogeneous black-coloured glasses with a smooth shiny surface were obtained after cooling. The vitrified bottom ashes were totally amorphous as confirmed by X-ray diffraction. The results from the present experimental work indicate that the examined bottom ashes can be a potential material to melt and to obtain a glass that can be further processed as glass-ceramics to be applied in construction. © 2007 Elsevier Ltd. All rights reserved.

Martins, Rui M. S., N. Schell, H. Reuther, L. Pereira, R. J. C. Silva, K. K. Mahesh, Braz F. M. Fernandes, AT Marques, AF Silva, APM Baptista, C. Sa, FJLA Alves, LF Malheiros, and M. Vieira. "Characterization of Ni-Ti (Shape Memory Alloy) Thin Film by in-situ XRD and Complementary ex-situ Techniques." Advanced Materials Forum Iv. Vol. 587-588. 2008. 672-676. Abstract
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Mateus, O. "Checklist for Late Jurassic reptiles and amphibians from Portugal." Livro de Resumos do X Congresso Luso-Espanhol de Herpetologia. Coimbra 2008. 55. Abstract
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Mateus, O. "Checklist for Late Jurassic reptiles and amphibians from Portugal." Livro de Resumos do X Congresso Luso-Espanhol de Herpetologia. Coimbra 2008. 55. Abstract
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Hayashi, S., K. Carpenter, M. Watabe, O. Mateus, and R. Barsbold. "Defensive weapons of thyreophoran dinosaurs: histological comparisons and structural differences in spikes and clubs of ankylosaurs and stegosaurs. 28 (3, Supplement), 89A-90A." Journal of Vertebrate Paleontology. 28 (2008): 89-90. Abstract
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Hayashi, S., K. Carpenter, M. Watabe, O. Mateus, and R. Barsbold. "Defensive weapons of thyreophoran dinosaurs: histological comparisons and structural differences in spikes and clubs of ankylosaurs and stegosaurs. 28 (3, Supplement), 89A-90A." Journal of Vertebrate Paleontology. 28 (2008): 89-90. Abstract
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Neagu, E. R., R. M. Neagu, C. J. Dias, M. C. Lanca, and J. N. Marat-Mendes. "The determination of the metal-dielectric interface barrier height from the open-circuit isothermal charging current." Journal of Applied Physics. 104 (2008). AbstractWebsite

There is a sustained interest both from theoretical and from practical points of view to understand the isothermal charging and the isothermal discharging currents in dielectrics. The measured currents are analyzed either in terms of polarization mechanisms or in terms of charge injection/extraction at the metal-dielectric interface and the conduction current through the dielectric material. As long as we do not know the nature of the origin of the current, it is not clear what information we can get by analyzing the experimental data. We propose to measure the open-circuit isothermal charging and discharging currents just to overpass the difficulties related to the analysis of the conduction mechanisms in dielectric materials. We demonstrate that besides a polarization current, there is a current related with charge injection or extraction at the metal-dielectric contact and a reverse current related to the charge trapped into the superficial trap states of the dielectric and that can jump at the interface in a reverse way. An analytical expression for the current is proposed. By fitting the experimental data to this analytical equation, two important parameters can be determined: (i) the highest value of the relaxation time for the polarization mechanisms still involved into the transient current and (ii) the height of the potential barrier W-0 at the metal-dielectric interface at the initial time when the step voltage is applied. The value obtained for Al-polyethylene terephthalate interface is (0.43 +/- 0.02) eV. For a charging voltage of 220 V there are 6x10(14) trapped electrons/m(2). (c) 2008 American Institute of Physics.

Neagu, E. R., R. M. Neagu, C. J. Dias, Carmo M. Lanca, and J. N. Marat-Mendes. "The determination of the metal-dielectric interface barrier height from the open-circuit isothermal charging current." Journal of Applied Physics. 104 (2008). Abstract
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Neagu, E. R., R. M. Neagu, C. J. Dias, Carmo M. Lanca, and J. N. Marat-Mendes. "The determination of the metal-dielectric interface barrier height from the open-circuit isothermal charging current." Journal of Applied Physics. 104 (2008). Abstract
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Monteiro, R. C. C., M. M. R. A. Lima, and C. S. Clemente. "Development of structural ceramics from fly ash and shale." Materials Science Forum. 587-588 (2008): 787-791. AbstractWebsite

The possibility of using fly ash and shale as alternative raw materials for the production of structural ceramics was investigated. Fly ash is a by-product from coal-burning power plants, and shale is a sedimentary rock that if ground finely enough can exhibit a clay-like plasticity. Ceramic samples containing 10-50 wt% fly ash were formed from mechanical mixing of both kinds of powders that were packed and sintered in the temperature range 950-1200°C It was verified that powders with larger fly ash content exhibited lower packing density resulting in compacts with a lower sintered density. Although an increase in fly ash content was associated to a larger presence of porosity in the sintered samples, as confirmed by microstructural analysis, all studied compositions when sintered at the highest temperatures exhibited satisfactory values for water absorption (< 10%), for flexural strength (20-64 MPa) and for hardness (20-30 GPa) indicating that they have potential to be applied in the production of structural ceramics.

Bras, A. R. E., O. Garcia, M. T. Viciosa, S. Martins, R. Sastre, C. J. Dias, J. L. Figueirinhas, and M. Dionisio. "Dielectric relaxation studies and electro-optical measurements in poly(triethylene glycol dimethacrylate)/nematic E7 composites exhibiting an anchoring breaking transition." Liquid Crystals. 35 (2008): 429-441. Abstract
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Mateus, O., LL Jacobs, M. J. Polcyn, AS Schulp, AB Neto, and MT Antunes. "Dinosaur and turtles from the Turonian of Iembe, Angola." Livro de Resumos de Tercer Congreso Latinoamericano de Paleontología de Vertebrados. Neuquén, Argentina 2008. 156. Abstract
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Mateus, O., LL Jacobs, M. J. Polcyn, AS Schulp, AB Neto, and MT Antunes. "Dinosaur and turtles from the Turonian of Iembe, Angola." Livro de Resumos de Tercer Congreso Latinoamericano de Paleontología de Vertebrados. Neuquén, Argentina 2008. 156. Abstract
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Mateus, O., M. Overbeeke, and F. Rita. "Dinosaur Frauds, Hoaxes and "Frankensteins": How to distinguish fake and genuine vertebrate fossils." Journal of Paleontological Techniques. 2 (2008): 1-5. Abstract
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Prabakaran, R., M. Peres, T. Monteiro, E. Fortunato, R. Martins, and I. Ferreira. "The effects of ZnO coating on the photoluminescence properties of porous silicon for the advanced optoelectronic devices." Journal of Non-Crystalline Solids. 354.19 (2008): 2181-2185. Abstract
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Lanca, M. C., S. Peuckert, E. R. Neagu, L. Gil, P. C. Silva, and J. Marat-Mendes. "Electrical Properties Studies of a Cork/TetraPak (R)/Paraffin Wax Composite." Advanced Materials Forum Iv. Eds. AT Marques, AF Silva, APM Baptista, C. Sa, FJLA Alves, LF Malheiros, and M. Vieira. Vol. 587-588. Materials Science Forum, 587-588. 2008. 613-617. Abstract

Lately the electrical and dielectric properties of cork and some cork-based materials (commercial and non-commercial) have been studied in order to understand their ability to store electrical charge. The main problem found so far is related to the water content in cork, only of a few % weight. but large enough to influence greatly the conductivity of cork and, consequently, the charge storage capability. To overcome this problem cork has been combined with hydrophobic materials. In this work a commercial wax (paraffin wax) was used to produce a cork/paraffin composite by hot pressing. After milled and mixed natural cork. TetraPak (R) containers waste and paraffin were pressed to make plaques of a new composite. Different concentrations of cork. TetraPak (R) and paraffin, different granules sire, different temperature and pressure were used to produce the samples. The electrical properties of the new composite were measured by the isothermal charging and discharging current method and the results compared to previously ones obtained for natural cork and other derivative products. The new composite has shown to have lower conductivity than the commercial agglomerate. which makes it a better material for charge storage.

Lanca, M. C., S. Peuckert, E. R. Neagu, L. Gil, P. C. Silva, and J. Marat-Mendes. "Electrical Properties Studies of a Cork/TetraPak (R)/Paraffin Wax Composite." Advanced Materials Forum Iv. 587-588 (2008): 613-617. AbstractWebsite

Lately the electrical and dielectric properties of cork and some cork-based materials (commercial and non-commercial) have been studied in order to understand their ability to store electrical charge. The main problem found so far is related to the water content in cork, only of a few % weight. but large enough to influence greatly the conductivity of cork and, consequently, the charge storage capability. To overcome this problem cork has been combined with hydrophobic materials. In this work a commercial wax (paraffin wax) was used to produce a cork/paraffin composite by hot pressing. After milled and mixed natural cork. TetraPak (R) containers waste and paraffin were pressed to make plaques of a new composite. Different concentrations of cork. TetraPak (R) and paraffin, different granules sire, different temperature and pressure were used to produce the samples. The electrical properties of the new composite were measured by the isothermal charging and discharging current method and the results compared to previously ones obtained for natural cork and other derivative products. The new composite has shown to have lower conductivity than the commercial agglomerate. which makes it a better material for charge storage.

Lanca, Carmo M., Stefan Peuckert, Eugen R. Neagu, Luis Gil, Paulo C. Silva, and Jose Marat-Mendes. "Electrical Properties Studies of a Cork/TetraPak (R)/Paraffin Wax Composite." Advanced Materials Forum Iv. Eds. AT Marques, AF Silva, APM Baptista, C. Sa, FJLA Alves, LF Malheiros, and M. Vieira. Vol. 587-588. Materials Science Forum, 587-588. 2008. 613-617. Abstract

Lately the electrical and dielectric properties of cork and some cork-based materials (commercial and non-commercial) have been studied in order to understand their ability to store electrical charge. The main problem found so far is related to the water content in cork, only of a few % weight. but large enough to influence greatly the conductivity of cork and, consequently, the charge storage capability. To overcome this problem cork has been combined with hydrophobic materials. In this work a commercial wax (paraffin wax) was used to produce a cork/paraffin composite by hot pressing. After milled and mixed natural cork. TetraPak (R) containers waste and paraffin were pressed to make plaques of a new composite. Different concentrations of cork. TetraPak (R) and paraffin, different granules sire, different temperature and pressure were used to produce the samples. The electrical properties of the new composite were measured by the isothermal charging and discharging current method and the results compared to previously ones obtained for natural cork and other derivative products. The new composite has shown to have lower conductivity than the commercial agglomerate. which makes it a better material for charge storage.