Search results for "RAV"

Polymer dynamics in thin p-type conducting films investigated by ac-electrogravimetry. Kinetics aspects on anion exclusion, free solvent transfer, an…

2015

A new transfer model is proposed to explain ac-electrogravimetry response of p-doped films. This model takes into account the exclusion effect occurring as a result of the anion transfer. The insertion/expulsion of anions inside a film involves simultaneously the expulsion/insertion of free solvent molecules. The number of solvent molecules excluded depends on the volume of anion transferred. Solvent transfer stimulated by the conformational changes of films constitutes the remaining electrogravimetric response when the exclusion process cannot explain by itself this response. Consequently, the kinetics of this free solvent transfer can be directly related to the kinetics of conformational …

Experimental investigation of the grain size dependence of the hydrolysis of LiH powder

2011

International audience; The hydrolysis reaction of LiH powder has been investigated in order to determine the products, rates and mechanisms of this reaction and the influence of the experimental parameters. Raman spectroscopy, X-ray diffraction and gravimetric analysis were used. It was shown that the product of hydrolysis was the hydroxide of lithium (LiOH) for low partial pressure of water (≈50 Pa) and LiOH*H2O for a higher partial pressure of water (>2000 Pa). Moreover, data obtained using gravimetric analysis inside a glove box containing a controlled partial pressure of water (500 ppmv/50 Pa at 25 °C) were used to determine the rate of the reaction versus particle size. The experiment…

El valencià a la xarxa: l'ús que en fan els jovens estudiants valencians

2015

Hem investigat una mostra poblacional de jóvens estudiants universitaris valencians, envers l'ús que fan de la xarxa i la presència de la llengua pròpia en aquella recerca, en el context dels altres àmbits relacionals 'estudi, carrer, oci, amics, ocupació, administració, comerç, cinema, televisió, videoconsoles...'. Així com mitjançant instruments tals com la telefonia mòbil o la tecnologia avançada.També hem analitzat la component afectiva que acompanya a l'ús de la llengua i apareixen, com a àmbits afavoridors, la família i la parella També hem esbrinat el grau de motivació i implicació envers el valencià i els estereotips d'introversió i extraversió que presenten els parlants. Pel que fa…

F-singularities via alterations

2011

For a normal F-finite variety $X$ and a boundary divisor $\Delta$ we give a uniform description of an ideal which in characteristic zero yields the multiplier ideal, and in positive characteristic the test ideal of the pair $(X,\Delta)$. Our description is in terms of regular alterations over $X$, and one consequence of it is a common characterization of rational singularities (in characteristic zero) and F-rational singularities (in characteristic $p$) by the surjectivity of the trace map $\pi_* \omega_Y \to \omega_X$ for every such alteration $\pi \: Y \to X$. Furthermore, building on work of B. Bhatt, we establish up-to-finite-map versions of Grauert-Riemenscheneider and Nadel/Kawamata-V…

Geometric Singularities of Curves and Surfaces and their Stereographical Images

1998

Removable singularities for div v=f in weighted Lebesgue spaces

2018

International audience; Let $w\in L^1_{loc}(\R^n)$ be apositive weight. Assuming that a doubling condition and an $L^1$ Poincar\'e inequality on balls for the measure $w(x)dx$, as well as a growth condition on $w$, we prove that the compact subsets of $\R^n$ which are removable for the distributional divergence in $L^{\infty}_{1/w}$ are exactly those with vanishing weighted Hausdorff measure. We also give such a characterization for $L^p_{1/w}$, $1<p<+\infty$, in terms of capacity. This generalizes results due to Phuc and Torres, Silhavy and the first author.

Spacetime curvature and Higgs stability after inflation

2015

We investigate the dynamics of the Higgs field at the end of inflation in the minimal scenario consisting of an inflaton field coupled to the Standard Model only through the non-minimal gravitational coupling $\xi$ of the Higgs field. Such a coupling is required by renormalisation of the Standard Model in curved space, and in the current scenario also by vacuum stability during high-scale inflation. We find that for $\xi\gtrsim 1$, rapidly changing spacetime curvature at the end of inflation leads to significant production of Higgs particles, potentially triggering a transition to a negative-energy Planck scale vacuum state and causing an immediate collapse of the Universe.

Split Bregman Method for Gravitational Wave Denoising

2014

This paper presents a progress report in our aim to develop a Total Variation algorithm for denoising of gravitational waves. These algorithms, are routinely employed in the context of image processing and they do not need any a priori information on the signals. We apply our method to two different types of numerically-simulated gravitational wave signals, namely burst produced from the core collapse of rotating stars and waveforms from binary black hole mergers, and present a preliminary assessment of its capabilities.

Non-supersymmetric black-hole solutions in N=2,D=4 supergravity

2013

254 páginas. Tesis Doctoral del Departamento de Física Teórica, de la Universidad de Valencia.

Violation of the equivalence principle from light scalar dark matter

2018

In this paper, we study the local observational consequences of a violation of the Einstein Equivalence Principle induced by models of light scalar Dark Matter (DM). We focus on two different models where the scalar field couples linearly or quadratically to the standard model of matter fields. For both these cases, we derive the solutions of the scalar field. We also derive from first principles the expressions for two types of observables: (i) the local comparison of two atomic sensors that are differently sensitive to the constants of Nature and (ii) the local differential acceleration between two test-masses with different compositions. For the linear coupling, we recover that the signa…