OLIVITRAN Nathalie
Organisme : CNRS
Chargé de Recherche
(HDR)
Nathalie.OliviTran
univmontp2.fr
0467144676
Bureau: 46.0, Etg: 3, Bât: 13  Site : Campus Triolet
Domaines de Recherche:  Physique/Matière Condensée/Science des matériaux
 Physique/Physique des Hautes Energies  Théorie
 Physique/Astrophysique/Cosmologie et astrophysique extragalactique
 Physique/Physique Quantique
 Physique/Relativité Générale et Cosmologie Quantique

Dernieres productions scientifiques :


Progressively doping graphene with Si: from graphene to silicene, a numerical study
Auteur(s): OliviTran N.
(Document sans référence bibliographique) 20150000
Ref HAL: hal01138887_v1
Résumé: For three different sizes of graphene nanosheets, we computed the Density of states when these nanosheets are progressively doped with an increasing percentage of Si atoms. The pure graphene nanosheets are semi conducting or not depending on their size. The pure silicene nanosheets are conducting with a conduction due to π electrons. The Si doped graphene nanosheets are also semi conducting or not depending on their size: for small sizes, there are semi conducting and they become conducting for larger sizes and larger percentages of Sidoping. We computed also the total electronic energy which is linked to the mechanical stability of all our nanosheets. This mechanical stability decreases regularly as a function of the Si percentage of doping , but for the pure silicene nanosheets, the mechanical stability decreases more abruptly.




Textural, Structural and Electrical Characterizations of EMI MAc Silica Ionogels and Their Corresponding Aerogels
Auteur(s): Bengourna Nadjette, Despetis F., Bonnet L., Courson R., Solignac P., Satha Hamid, OliviTran N.
(Article) Publié:
Applied Physics Research, vol. 6 p.16 (2014)
Ref HAL: hal01061376_v1
DOI: 10.5539/apr.v6n4p16
Résumé: Silica ionogels were synthesized from tetramethoxysilane (T MOS ),methyltrimethoxysilane (MT MS ) and 1ethyl 2methylimidazolium Acetate (EMI MAc: Ionic Liquid) in different proportions .The textural characterizations showed an effect of these concentrations on the corresponding aerogels: pore size distributions and effective surfaces. The structure of the aerogels was measured with a SAXS (Small Angle XRay Scattering) apparatus and was typical of acid catalyzed aerogels. Conductivity voltage measurements, operated on the ionogels, were carried out using an electrical 4 wireelectrodes set up. The electrical voltage temporal response of the EMIMAc silica ionogel was modelled by a RLC series circuit which characteristics depended on the synthesis.




The masses of the first family of fermions and of the Higgs boson are equal to integer powers of 2
Auteur(s): OliviTran N.
(Article) Publié:
Advanced Studies In Theoretical Physics, vol. 8 p.511516 (2014)
Ref HAL: hal00998959_v1
DOI: 10.12988/astp.2014.4449
Résumé: We noticed that the first family of fermions and the Higgs boson have masses which are equal to integer powers of 2 in $eV/c^2$ units (i.e. in the Planck length units). We made the hypothesis that, if spacetime is composed of small hypercubes of one Planck length edge, it exists elementary wavefunctions which are equal to $\sqrt{2} \exp (ikx_i)$ if it corresponds to a space dimension or equal to $\sqrt{2} \exp (i \omega t)$ if it corresponds to a time dimension. By using the Dirac propagation equation and combinatorics we showed that the electron has a mass of $2^{19}eV/c^2$, the quark has a mass of $2^{21}eV/c^2$ and the electron neutrino has a mass of $2eV/c^2$. Finally, the Higgs boson is showed to have a mass of $2^{37}eV/c^2$.




A classification of elementary particles in d=4 following a simple geometrical hypothesis in real space
Auteur(s): OliviTran N., Gottiniaux Nicolas
(Article) Publié:
Advanced Studies In Theoretical Physics, vol. 7 p.853  857 (2013)
Ref HAL: hal00853870_v1
DOI: 10.12988/astp.2013.3778
Résumé: We made the hypothesis that our universe is fourdimensional: time $t$ is treated as a 'regular' dimension. So in the $(t,x,y,z)$ coordinates system, we present a simple approach of all the elementary particles which might be four,three and twodimensional. This hypothesis leads to a unified approach of all particles.




And if there was no need of dark energy to explain the acceleration of the expansion of the universe?
Auteur(s): OliviTran N.
(Article) Publié:
Advanced Studies In Theoretical Physics, vol. 7 p.467  470 (2013)
Ref HAL: hal00818845_v1
DOI: 10.12988/astp
Résumé: In order to explain the fact that the pressure in the Friedmann equations is negative, only the hypothetical presence of dark energy is used in present theories. But, the dimensions of the pressure $p$ are $f/r^2$ and thus $p$ can not account for the acceleration of the expansion of the universe. Indeed, the hypersurface of our universe is threedimensional and curved, so a force has an effect on the universe if it is applied on the universe's boundaries. As these boundaries (hypersurface) correspond to the threedimensional universe itself at time $t$, there must exist a positive force density $f/r^3$. The relation between the pressure $p$ (calculated within the Friedmann model) and the force density is a simple derivation with respect to $r$ the space variable. And the derivation of a negative pressure leads to a positive force density.
Commentaires: Open Access Journal


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