UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS

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Conference: Bucharest University Faculty of Physics 2013 Meeting


Section: Optics, Spectroscopy, Plasma and Lasers


Title:
Laser induced modifications on colloidal systems and measurement of their properties


Authors:
V.Nastasa, K. Samaras, T. Karapantsios, M.L. Pascu


Affiliation:
1. National Institute for Laser Plasma and Radiation Physics, Bucharest, Romania

2. Aristotle University, Chemistry Department, Thessaloniki, Greece


E-mail
viorel.nastasa@inflpr.ro


Keywords:
light scatering, laser, emulsion, foams, nano droplets


Abstract:
Emulsions are defined as heterogeneous systems of one liquid dispersed in another in droplet form with droplets sizes that range from nanometer scale up to 100 μm in diameter and with each droplet having a monolayer of surfactant or emulsifier molecules as a coating [1]. Usually, the two implied liquid phases are immiscible, chemically unreactive, and the systems which they form are thermodynamically unstable [2]. Emulsions may consist of oil droplets dispersed in a continuous water phase (oil-in-water) or of water droplets dispersed in a continuous oil phase (water-in-oil) function of the oil/water ratio, the concentration of the surfactant used in the emulsification process and other parameters like the presence or absence of electrolytes, temperature, and pressure [3] It was proven that the exposure to laser radiation can lead to molecular modification and therefore to a modification of the irradiated substance [4]. The resonant interaction with a surfactant substance leads to the modification of the surface adsorption at the water/air interface which could lead to a modification of the emulsification parameters and therefore to an increase stability of the obtained emulsion. This study tries to determine the effects of laser radiation on the surfactants used in food emulsions and reports results on the droplet dimensions obtained with different emulsification techniques. References: [1] K. Shinoda, S. Friberg, Emulsions and Solubilization, Wiley, New York, 1986. [2] S.G. Oh, M. Jobalia, D.O. Shah, J. Colloid Interface Sci. 156 (2) (1993) 511–514. [3] P. Becher, Emulsions: Theory and Practice, second ed., Reinhold, New York, 1965. [4] M.L. Pascu, B. Danko, A. Martins, N. Jedlinszki, T. Alexandru, V. Nastasa, M. Boni, A. Militaru, I. R. Andrei, A. Staicu, A. Hunyadi, S. Fanning, L. Amaral Exposure of Chlorpromazine to 266 nm Laser Beam Generates New Species with Antibacterial Properties: Contributions to Development of a New Process for Drug Discovery, PLoS ONE, 2013 Acknoledgements: This work was supported by the ANCS (RO) project LAPLAS 3-PN 09 33, Project Parteneriate 85/2012 (AMPLE), COST Action MP1106,