Defining the importance of landscape metrics for large branchiopod biodiversity and conservation: the case of the Iberian Peninsula and Balearic Islands

The deficiency in the distributional data of invertebrate taxa is one of the major impediments acting on the bias towards the low awareness of its conservation status. The present study sets a basic framework to understand the large branchiopods distribution in the Iberian Peninsula and Balearic Islands. Since the extensive surveys performed in the late 1980s, no more studies existed updating the information for the whole studied area. The present study fills the gap, gathering together all available information on large branchiopods distribution since 1995, and analysing the effect of human population density and several landscape characteristics on their distribution, taking into consideration different spatial scales (100 m, 1 km and 10 km). In overall, 28 large branchiopod taxa (17 anostracans, 7 notostracans and 4 spinicaudatans) are known to occur in the area. Approximately 30% of the sites hosted multiple species, with a maximum of 6 species. Significant positive co-occurring species pairs were found clustered together, forming 4 different associations of large branchiopod species. In general, species clustered in the same group showed similar responses to analysed landscape characteristics, usually showing a better fit at higher spatial scales.Brazilian Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq [401045/2014-5]Spanish Ministry of Education, Culture and Sport [FPU014/06783]info:eu-repo/semantics/publishedVersio

Ballistic performance of dry stacked flax fabrics

Natural fibres have received a growing interest from the composite community over the last decade because they offer a low cost and environmentally friendly alternative to conventional reinforcing fibres. Natural fibre reinforced materials are currently used in different domains such as the automotive industry for example. However, there are only few works in literature on the ballistic protection offered by natural fibres. Combining natural fibres with stronger synthetic fibres to form “hybrid” composites could nevertheless offer an optimal balance between performance and cost. This work focuses on the behaviour of flax fibres under ballistic impact in order to evaluate their potential incorporation into lightweight ballistic armour. The ballistic limit (V50) of dry flax woven fabrics was studied. We observed that dry fabrics impacted by fragment simulating projectiles (FSP) exhibit a higher ballistic limit than in previous tests where flax was incorporated as fiber reinforcement into composites with polypropylene matrix. The influence of the protection's thickness on V50 was evaluated. Different kinds of woven structures were also studied and the behaviour of those fabrics under impact is briefly described

Development of low cost composite plates for humanitarian demining operations

Composite plates using flax fabrics and maleic anhydride modified polypropylene were fabricated on laboratory scale. The aim of the current research was to develop a low cost composite plate or a hybrid structure based on those plates and steel sheet, for making humanitarian demining clothes protecting against secondary fragmentation caused by anti-personnel blast mines. Ballistic impact tests according to STANAG 2920 were carried out for determining the v(50)-limit. So called field tests were performed by means of simulated anti-personnel mines using M112 explosive; the repeatability and the spatial distribution of the projected fragments were checked before fixing the final experimental setup. The performance of the bare composite plate was compared with the hybrid structures in terms of v(50) and in terms of damage mechanisms. All tested configurations performed amazingly well during the field tests, which was not the case for the ballistic impact tests. This led to the conclusion that v(50) might not be the best criterion to characterize protective clothing. This conclusion is sustained by energetic considerations and by field tests on plates with half the thickness of the initial plates.status: publishe

A multi-scale characterization of deformation twins in Ti6Al4V sheet material deformed by simple shear

International audienceTi6Al4V sheet material is subjected to simple shear deformation with strain ratio's of 10%, 30% and 50%. Optical microscopy, transmission electron microscopy and electron backscatter diffraction techniques are applied to study the presence and morphology of deformation twins. Only the type of twins seems to be present with a volume fraction below 1%. These twins show a high density of basal stacking faults of the …ABABACAC… type identified using atomic resolution transmission electron microscopy. A resolved shear stress analysis shows that twins most often occur on those planes with the highest resolved shear stresses, but that the starting texture is not beneficial for the occurrence of twins. It is further suggested that a transitory strain hardening regime observed around 530 MPa might be related with the onset of twinning

Texture evolution in linear friction welded Ti-6Al-4V

The linear friction welding (LFW) behavior of Ti-6Al-4V, a commercial \u3b1 + \u3b2 titanium alloy, was investigated using oscillation frequencies ranging from 30-70 Hz and axial pressures from 50-110 MPa. LFW samples were examined using electron backscattered diffraction (EBSD) to relate the texture to the welding parameters and to the estimated strain and strain rate. Characterization of the welds included analysis of the microstructure of the weld and of the thermomechanically affected zones (TMAZ) in relation to the parent material.Peer reviewed: YesNRC publication: Ye

Development of low cost composite plates for humanitarian demining operations

Composite plates using flax fabrics and maleic anhydride modified polypropylene were fabricated on laboratory scale. The aim of the current research was to develop a low cost composite plate or a hybrid structure based on those plates and steel sheet, for making humanitarian demining clothes protecting against secondary fragmentation caused by anti-personnel blast mines. Ballistic impact tests according to STANAG 2920 were carried out for determining the v$_{50}$-limit. So called field tests were performed by means of simulated anti-personnel mines using M112 explosive; the repeatability and the spatial distribution of the projected fragments were checked before fixing the final experimental setup. The performance of the bare composite plate was compared with the hybrid structures in terms of v$_{50}$ and in terms of damage mechanisms. All tested configurations performed amazingly well during the field tests, which was not the case for the ballistic impact tests. This led to the conclusion that v$_{50}$ might not be the best criterion to characterize protective clothing. This conclusion is sustained by energetic considerations and by field tests on plates with half the thickness of the initial plates