Fractal analysis of molecular brownian motion in liquids was carried out in two and three dimensi... more Fractal analysis of molecular brownian motion in liquids was carried out in two and three dimensions. It was observed that the trajectories are self-affine and can be characterized by a differential fractal dimension, which varies with the trajectory length. The analysis of the brownian motion by different kinds of coverings, and the comparison of this motion with diffusion-limited processes, allows us to deduce that the ensemble of all trajectories has a multifractal structure. Finally, the brownian motion in disordered media was studied. Significant differences were found depending on the euclidean dimension in which the motions were performed.
Finite Brownian motion can be characterized as an effective multifractal since different spatial ... more Finite Brownian motion can be characterized as an effective multifractal since different spatial regions have different scaling properties. The homogenization of the spatial probability distribution as the length of the Brownian trajectory increases is reflected in an effective diffusion coefficient, which approaches the theoretical diffusion coefficient when the trajectory length is long enough to exhibit the global statistical properties of ideal Brownian motion.
Ability to control the metal arrangement in bimetallic nanocatalysts is the key to improving thei... more Ability to control the metal arrangement in bimetallic nanocatalysts is the key to improving their catalytic activity. To investigate how metal distribution in nanostructures can be modified, we developed a computer simulation model on the synthesis of bimetallic nanoparticles obtained in microemulsions by a one-pot method. The calculations allow predicting the metal arrangement in nanoparticle under different experimental conditions. We present results for two couples of metals, Au/Pt (Δε=0.26 V) and Au/Ag (Δε=0.19 V), but conclusions can be generalized to other bimetallic pairs with similar difference in standard reduction potentials. It was proved that both surface and interior compositions can be controlled at nanometer resolution easily by changing the initial reactant concentration inside micelles. Kinetic analysis demonstrates that the confinement of reactants inside micelles has a strong effect on the reaction rates of the metal precursors. As a result, the final nanocatalys...
Fractal analysis of molecular brownian motion in liquids was carried out in two and three dimensi... more Fractal analysis of molecular brownian motion in liquids was carried out in two and three dimensions. It was observed that the trajectories are self-affine and can be characterized by a differential fractal dimension, which varies with the trajectory length. The analysis of the brownian motion by different kinds of coverings, and the comparison of this motion with diffusion-limited processes, allows us to deduce that the ensemble of all trajectories has a multifractal structure. Finally, the brownian motion in disordered media was studied. Significant differences were found depending on the euclidean dimension in which the motions were performed.
Finite Brownian motion can be characterized as an effective multifractal since different spatial ... more Finite Brownian motion can be characterized as an effective multifractal since different spatial regions have different scaling properties. The homogenization of the spatial probability distribution as the length of the Brownian trajectory increases is reflected in an effective diffusion coefficient, which approaches the theoretical diffusion coefficient when the trajectory length is long enough to exhibit the global statistical properties of ideal Brownian motion.
Ability to control the metal arrangement in bimetallic nanocatalysts is the key to improving thei... more Ability to control the metal arrangement in bimetallic nanocatalysts is the key to improving their catalytic activity. To investigate how metal distribution in nanostructures can be modified, we developed a computer simulation model on the synthesis of bimetallic nanoparticles obtained in microemulsions by a one-pot method. The calculations allow predicting the metal arrangement in nanoparticle under different experimental conditions. We present results for two couples of metals, Au/Pt (Δε=0.26 V) and Au/Ag (Δε=0.19 V), but conclusions can be generalized to other bimetallic pairs with similar difference in standard reduction potentials. It was proved that both surface and interior compositions can be controlled at nanometer resolution easily by changing the initial reactant concentration inside micelles. Kinetic analysis demonstrates that the confinement of reactants inside micelles has a strong effect on the reaction rates of the metal precursors. As a result, the final nanocatalys...
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