Suchergebnisse

In recent years, continuous fibre reinforced thermoplastic matrix composites have been successfully employed in the aircraft, military and aerospace industries due to the excellent properties (Brandt et al. 1993 & Nunes et al 2005a). In these and many other commercial engineering applications, they can replace other materials, such as thermosetting matrix composites. However, the high cost of the impregnation of continuous fibre thermoplastic composites, arising from the melting of the polymer or the use of solvents, still restricts their use in commercial applications. Hence, cost reduction largely depends on developing more efficient methods for impregnating fibres with high-viscosity thermoplastics and for processing final composite parts. This chapter summarizes the development of new technologies to fabricate long and continuous fibre reinforced composite structures from thermoplastic matrix semi-products (towpregs and PCT – pre-consolidated tapes) for commercial and highly demanding markets. The production of continuous fibre reinforced thermoplastic matrix towpregs and PCT's was done using a recently developed coating line (Nunes et al. 2008, 2010 & Silva, R.F. et al. 2008). Using this prototype equipment, it was possible to produce glass fibre polypropylene (PP) and polyvinylchloride (PVC) towpregs for commercial markets and towpregs from carbon fibres and Primospire®, an amorphous highly aromatic material developed by Solvay Advanced Polymers, for application in advanced markets (Nunes et al. 2005, 2009 & Silva, J. F. et al. 2010). To process these thermoplastic pre-pregs into composite structures, conventional thermosetting equipments were adapted to fabricate thermoplastic matrix composites. Filament winding, pultrusion and hot compression moulding were the studied technologies. The mechanical properties determined on the final composites were compared with the theoretical predictions and have shown to be acceptable for the targeted markets. As applications, filament wound pressure vessels ...

Alkali–aggregate reactions have been known for decades although the acceptance of their occurrence has been delayed in some countries until the 1990s. Potential reactivity has been identified in most of the rock types used as aggregates around the world. The most common reactive rocks are sedimentary (e.g. opaline sandstone) and metamorphic (e.g. gneiss). However, igneous rocks such as granites have also proved to be reactive in some areas and innocuous in many other regions. It has been concluded that the designation is not enough to label a rock as reactive and that microstructure is very often the determinant factor of reactivity. In the present study a summary ismade on the state-of-the-art on alkali– aggregate reactions. Emphasis is given on the identification of potentially reactive aggregates based on petrographic methods. Examples from a large number of samples analysed in the scope of a research project are presented. ; The authors would like to acknowledge Centro de Geologia (University of Porto), Fundac¸a˜o para a Cieˆncia e Tecnologia for the financial support of the Project IMPROVE (Ref: PTDC/ECM/115486/2009), and Azorean Regional Government for financial support of Project ReAVA. The SEM-EDX data were obtained at the Materials Centre of the University of Porto (CEMUP) whose equipment was funded by the projects REEQ/1062/CTM/2005 and REDE/1512/RME/2005 of FCT. ; 3 ; 1 ; 10p ; DM/NMM ; Proceedings of the ICE - Construction Materials

Carbon Fibre Reinforced Polymers (CFRP) have been widely used in advanced markets, such as, the aeronautic, aerospace and military ones. Despite their extraordinary mechanical properties and low density, advanced composites, due to their intrinsic brittleness and layer-by-layer nature, present some vulnerability when submitted to impact, dynamic and flexural loading. Low velocity impacts (LVI) are one of the most dangerous events that composite laminate can face in their life time. These solicitations may develop imperceptible internal laminate damages, namely delaminations, that tend of propagate in service, compromising part performance. In order to improve interlaminar crack propagation, some works were already carried out using interleaved thin veils between laminate layers to enhance the interlaminar Mode I and II fracture toughness. In this work, a study was carried out on the distribution of stresses across the thickness of a carbon/epoxide laminate typically used in structural aircraft components, to define between which specific layers would be better to interleave thin veils made from four different materials (glass, carbon, aramid and polyester) to achieve better LVI damage tolerance. Samples made from the selected structural carbon/epoxy laminate were then produced by vacuum bag infusion with those thin veils located between their most appropriated layers to be submitted experimental testing and compare their mechanical and LVI performances with those without using interleaved veils. All studied laminates were observed under scanning electron microscopes (SEM) for assessing their processing quality and submitted to interlaminar shear strength (ILSS) and LVI tests to evaluate their delamination resistance and impact response, respectively. ; FCT, Programa MIT Portugal, projeto ...

Volcanic rocks have been found to be potentially alkali-reactive in a number of countries, including Japan, New Zealand, Iceland and Turkey. In order to characterize the potential reactivity of the volcanic rocks in Azores a project is being carried out, under the support of the Azores Government: the ReAVA Project—"Characterization of Potential Reactivity of the Volcanic Aggregates from the Azores Archipelago: Implications on the Durability of Concrete Structures". This project comprises mainly: (1) petrographic assessment of the aggregates, (2) assessment of their performance in expansion tests and (3) site inspection of existing large concrete structures. This study has also the support of the IMPROVE Project—"Improvement of Performance of Aggregates in the Inhibition of Alkali-Aggregate Reactions in Concrete", aiming to minimize the occurrence of alkali aggregate reaction (AAR) in Portugal. The Azorean rocks used as aggregates are mainly basalts and some trachytes. The reactivity of this kind of rocks is usually associated with the presence of volcanic glass, altered minerals and SiO2 content of the rock. The petrographic examinations of the rocks confirmed that one of the basaltic samples contains volcanic glass. The occurrence of microcrystalline quartz as a secondary product filling the interstices of the trachyte sample was confirmed by scanning electron microscope. The results of the concrete expansion test RILEM AAR-3 showed an increasing expansion starting on 140 days and continued to grow after 2 years of laboratory testing, but below the limit of 0.05 % recommended for this method. ; 51-54pp ; The analyses by SEM/EDS were performed at CEMUP which equipment was funded by the projects REEQ/1062/CTM/2005 and REDE/1512/RME/2005 of Portuguese Foundation for Science and Technology (FCT). The authors also acknowledge the financial support of the FRC under the project M5.2.2/I/05/2011 and FCT under the project PTDC/ECM/15486/2009. ; 5 ; DM/NMM ; Urban Geology, Sustainable Planning and Landscape Exploitation

International audience ; In order to further allow implementation of breeding programs in local pig breeds, with selection objectives defined for each local breed, we aimed at developing a standardised recording of carcass and meat quality traits. These data have to be connected with herdbooks to estimate genetic parameters of the traits (heritabilities and genetic correlations) which are necessary to define breeding objectives. Today the situation is very different from one local breed to another. No or very few phenotypes are recorded in some of them, while breeding programs already exist for a few breeds. To promote phenotyping, a dedicated database and a website were developed in the frame of the TREASURE project. First, the required variables have been collected for six local breeds: Basque (FR), Bísaro (PT), Crna slavonska (HR), Gascon (FR), Krškopoljski (SI) and Schwäbisch-Hällisches (DE). In total 74 variables have been identified dealing with animal herdbook information (10), rearing and growth (22), carcass (22) and meat quality (20) attributes. The database is compatible with the various identifiers used in the different countries: animal IDs, breed, farm… codifications. Major attention has been paid to the description of measurement methods of traits. Thus, each carcass and meat quality phenotype is associated to a method description representing 35 additional variables. The website can be easily translated into several languages. The website and database are currently on test until the end of the TREASURE project. All the breeds studied in TREASURE are free to use these tools. The database can be duplicated so that each partner can host its own data. Funded by European Union H2020 RIA program (grant agreement no. 634476).

In order to further allow implementation of breeding programs in local pig breeds, with selection objectives defined for each local breed, we aimed at developing a standardised recording of carcass and meat quality traits. These data have to be connected with herdbooks to estimate genetic parameters of the traits (heritabilities and genetic correlations) which are necessary to define breeding objectives. Today the situation is very different from one local breed to another. No or very few phenotypes are recorded in some of them, while breeding programs already exist for a few breeds. To promote phenotyping, a dedicated database and a website were developed in the frame of the TREASURE project. First, the required variables have been collected for six local breeds: Basque (FR), Bísaro (PT), Crna slavonska (HR), Gascon (FR), Krškopoljski (SI) and Schwäbisch-Hällisches (DE). In total 74 variables have been identified dealing with animal herdbook information (10), rearing and growth (22), carcass (22) and meat quality (20) attributes. The database is compatible with the various identifiers used in the different countries: animal IDs, breed, farm… codifications. Major attention has been paid to the description of measurement methods of traits. Thus, each carcass and meat quality phenotype is associated to a method description representing 35 additional variables. The website can be easily translated into several languages. The website and database are currently on test until the end of the TREASURE project. All the breeds studied in TREASURE are free to use these tools. The database can be duplicated so that each partner can host its own data. Funded by European Union H2020 RIA program (grant agreement no. 634476).

In order to further allow implementation of breeding programs in local pig breeds, with selection objectives defined for each local breed, we aimed at developing a standardised recording of carcass and meat quality traits. These data have to be connected with herdbooks to estimate genetic parameters of the traits (heritabilities and genetic correlations) which are necessary to define breeding objectives. Today the situation is very different from one local breed to another. No or very few phenotypes are recorded in some of them, while breeding programs already exist for a few breeds. To promote phenotyping, a dedicated database and a website were developed in the frame of the TREASURE project. First, the required variables have been collected for six local breeds: Basque (FR), Bísaro (PT), Crna slavonska (HR), Gascon (FR), Krškopoljski (SI) and Schwäbisch-Hällisches (DE). In total 74 variables have been identified dealing with animal herdbook information (10), rearing and growth (22), carcass (22) and meat quality (20) attributes. The database is compatible with the various identifiers used in the different countries: animal IDs, breed, farm… codifications. Major attention has been paid to the description of measurement methods of traits. Thus, each carcass and meat quality phenotype is associated to a method description representing 35 additional variables. The website can be easily translated into several languages. The website and database are currently on test until the end of the TREASURE project. All the breeds studied in TREASURE are free to use these tools. The database can be duplicated so that each partner can host its own data. Funded by European Union H2020 RIA program (grant agreement no. 634476).

The Smalleye Hammerhead (Sphyrna tudes) is a medium-sized (to 150 cm total length) shark that occurs in the Western Central and Southwest Atlantic from Colombia to the Rio de La Plata, Argentina. It inhabits inshore waters over the continental shelf at depths of 5–80 m. It is captured in intense and largely unmanaged commercial and artisanal beach seines, gillnets, longlines, and trawls throughout its geographic range. This shark is targeted or retained as bycatch for its meat, which is consumed or sold locally. There are few data on population reduction but these intensive unmanaged fisheries are suspected to have caused reductions and possibly local extinctions throughout this species' range. For example, in Brazil, this hammerhead has not been recorded in 35 years from Ceará state and it is considered by local fishers to be depleted in Bahia state. This shark is supposed to be strictly protected in Brazil, but it is clear that it is still landed and traded in various states. Overall, due to intense and largely unmanaged fisheries across its range, lack of refuge at depth, suspected declines in many areas and local extinctions suspected from an absence of records (despite continued sampling and observation), and its relatively unproductive life history, it is suspected that the Smalleye Hammerhead has undergone a population reduction of >80% over the past three generations (37 years), and it is assessed as Critically Endangered A2bd. ; Fil: Pollom, R. University Fraser Simon; Canadá ; Fil: Barreto, R. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil ; Fil: Charvet, P. Universidade Federal do Paraná; Brasil ; Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina ; Fil: Cuevas, J. M. Wildlife Conservation Society; Estados Unidos ; Fil: Faria, V. Universidade Federal Do Ceara; Brasil ; Fil: Herman, K. Georgia Aquarium; Estados Unidos ; Fil: Lasso Alcala, O. Fundación la Salle de Ciencias Naturales; Venezuela ; Fil: Marcante, F. Universidade Federal Do Rio Grande.; Brasil ; Fil: Mejía Falla, P.A. Wildlife Conservation Society; Estados Unidos ; Fil: Montealegre Quijano, S. Universidade Federal de Sao Paulo; Brasil ; Fil: Motta, F. Universidade Federal de Sao Paulo; Brasil ; Fil: Navia, A. F. Fundación Squalus; Colombia ; Fil: Nunes, J. Universidade Federal Do Maranhao.; Brasil ; Fil: Paesch, L. Dirección Nacional de Recursos Acuáticos; Uruguay ; Fil: Rincon, G. Universidade Federal Do Maranhao.; Brasil