Angélina Razafitianamaharavo

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Introduction: Carbonaceous chondrites contain trapped noble gases that are present in different carriers. The most abundant carrier, known as "planetary"-also referred to as "Q" or "P1" [1]-is formed of carbonaceous material, the nature of which remains ill-defined. It appears to be mainly composed of aromatic moieties linked by short aliphatic chains for(More)
Al-Fe oxyhydroxy co-precipitates were synthesised by forced hydrolysis of Fe(NO3)3·9H2O and Al(NO3)3·9H2O solutions. Solids containing 0, 1, 10, 25, 50, 75, 90 mol% Al were characterised for composition, texture, mineral structure and local atomic environment. Cation substitution in the hydrous oxides was not observed. The solids consisted of hydrous ferric(More)
Textural and energetic proprieties of kaolinite were studied by low-pressure argon adsorption at 77 K. The heterogeneity of four kaolinites (two low-defect and two high-defect samples) modified on their surface by cation exchange with Li+, Na+, or K+ was studied by DIS analysis of the derivative argon adsorption isotherms. The comparison between the(More)
Surface heterogeneity can be assessed by adsorption of different gaseous probes on solid materials. In the present study, four types of activated carbons were analyzed by classical N2 Brunauer-Emmett-Teller (BET) measurements and by low-pressure quasi-equilibrium volumetry (LPQEV) (Villieras, F.; Michot, L. J.; Bardot, F.; Cases, J. M.; Francois, M.;(More)
DDB2, known for its role in DNA repair, was recently shown to reduce mammary tumor invasiveness by inducing the transcription of IκBα, an inhibitor of NF-κB activity. Since cellular adhesion is a key event during the epithelial to mesenchymal transition (EMT) leading to the invasive capacities of breast tumor cells, the aim of this study was to investigate(More)
The distribution of edge and basal surface areas of phyllosilicate particles is an essential parameter for understanding the interaction mechanisms at solid/gas or solid/liquid interfaces. Among the techniques proposed to determine the geometrical heterogeneities of flat solids, low-pressure argon adsorption and AFM analysis are the most promising to derive(More)
Relationships between structural parameters of MnO2 and their surface properties at the solid-gas interface were investigated. The studied series ranged from ramsdellite to pyrolusite and encompassed disordered gamma-MnO2 samples. The structural model used takes into account structural defects: Pr (rate of pyrolusite intergrowth in the ramsdellite network)(More)
Mechanical and conformational properties of type 1 fimbriae were evaluated on live bacterial cells by Single Molecule Force Spectroscopy (SMFS) and Dynamic Force Spectroscopy (DFS) in buffered solutions whose pH varied from 3 to 9. We evidenced that both fimbrial extension and fimbrial binding force to mannosylated-surface are modulated with changing the(More)
Two clays of the areas of Kaélé and Kousseri (extreme North Cameroon) containing mainly smectites and minor amounts of kaolinite were activated with sulfuric acid (1 to 8 N). Crystal-chemical properties were studied using X-ray diffraction, Fourier transform infrared spectroscopy, and chemical analysis, while textural properties were analyzed by(More)
BACKGROUND Liposomes are currently an important part of biological, pharmaceutical, medical and nutritional research, as they are considered to be among the most effective carriers for the introduction of various types of bioactive agents into target cells. SCOPE OF REVIEW In this work, we study the lipid organization and mechanical properties of(More)
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