Search results for "Composites"
showing 10 items of 1905 documents
Influence of Grain Size, Oxygen Stoichiometry, and Synthesis Conditions on the γ-Fe2O3 Vacancies Ordering and Lattice Parameters
2002
The soft chemistry method has been used to synthesize γ-Fe2O3 nanoparticles: various synthesis temperature were applied to obtain nanometric powders with crystallite size in the 9–14 nm range. Powders were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectrophotometry, surface area measurements, and electron microscopy (TEM, SEM). It is clearly shown that these nanometric powders are very well crystallized as indicated by XRD and IR spectra which present substructural bands attributed to vacancies ordering (P4132). Based on these model materials and in the crystallite size range studied here, cell parameter appears to be not linked to crystallite size. It rat…
New hydrogel matrices containing an anti-inflammatory agent. Evaluation of in vitro release and photoprotective activity.
2002
In the present work. the preparation and characterization of hydrogels based on alpha,beta-polyaspartylhydrazide (PAHy) chemically crosslinked with ethyleneglycol diglycidylether (EGDGE) containing Tolmetin sodium salt, are reported. In particular, these samples have been prepared both as water swellable microparticles and as gels at two different crosslinking degrees. The incorporation of Tolmetin sodium salt in PAHy-EGDGE microparticles has been performed after the crosslinking reaction by a soaking procedure or during the formation of the network. The influence of drug loading procedure on Tolmetin release has been evaluated by performing in vitro release study in simulated gastrointesti…
Perfluoroalkylated amphiphilic MUC1 glycopeptide antigens as tools for cancer immunotherapy.
2010
The synthesis of perfluoroalkylated glycopeptide antigens and their specific binding to anti-MUC1 mouse antibodies is reported.
Hybrid nanocomposites with ultra-low filling content by nano-coating fragmentation
2021
In the current study, a new technique for the manufacturing of polymer nanocomposites (PNCs) with ultra-low filling content (<0.05 wt%) is presented. Specifically, this method has been validated through the production of polypropylene (PP) nanocomposites with Ag nanoparticles. The presented method first consisted in a metal nano-film deposition on PP pellet substrates by a physical vapor deposition (PVD) sputtering equipment. Subsequently, a percentage of the coated pellet was mixed to uncoated ones via an injection molding machine to produce the PNC in a single step. Different mixing percentages of coated PP pellet to the uncoated ones were studied. As a result, the fragmentation of the…
Détection d'endommagement dans les composites à l'aide d'une technologie utilisant des micro-ondes et par thermographie infrarouge
2010
National audience; On présente dans cette étude deux méthodes de détection d'endommagement dans les composites : une basée sur la technologie des structures propagatives électromagnétiques dans la gamme des micro-ondes et l'autre basée sur la mesure de champs thermiques dans la gamme des infrarouges. Toutes deux sont appliquées à la détection des ruptures de fibres et du délaminage dans des composites fibres/résine de type verre/époxy et carbone/époxy. La méthode par micro-onde est fondée sur les modifications des propriétés diélectriques d'un milieu lors d'un endommagement. Elle analyse les modifications de l'onde réfléchie d'une onde transmise dans le matériau vue comme une structure prop…
Détection des ruptures de fibres et du délaminage dans les composites verre/époxy et carbone/époxy à l'aide de structures propagatives dans la gamme …
2009
National audience; On présente dans cet article la détection de ruptures de fibre et du délaminage dans les composites unidirectionnels verre/époxy et carbone/époxy en utilisant des structures propagatives électromagnétiques dans la gamme des micro-ondes.
Détection d'endommagement dans les composites à l'aide de la technologie micro-onde
2007
6-8 juin 2007; National audience
Predicting stiffness and strength of birch pulp:Polylactic acid composites
2016
This paper studies failure of birch pulp–polylactic acid composites. Stiffness and strength are calculated using the theory of short fibre composites and the results are compared to experimental data. The results differed from the experimental values by 0–6%. With less aligned fibres the short fibre theory is not feasible. The performance of the 40 wt% birch pulp – polylactic acid composite is predicted with X-ray microtomography based finite element modelling, and the results are compared with experiments. Stiffness results differed from experiments by 1–17% . By adding into the models a third material phase representing the interface between the fibres and the matrix, the stress–strain c…