Laboratorio de Dispersiones e Interfases, Instituto Venezolano de Investigaciones Científicas.


Address: Carretera Panamericana, Km. 11. Altos de Pipe. Caracas, Venezuela.
Centro de Estudios Interdisciplinarios de la FísicaInstituto Venezolano de Investigaciones Científicas.
Phone: +58-212-5041587
Fax: +58-212-5041915

E-mail: jtorom@ivic.gob.ve, jhoantoro@yahoo.com.ar

Nueva Magister en Física Aplicada
El pasado 31 de Enero de 2014, Jaqueline Fernández defendió su tesis para obtener el título de Master en Física Aplicada de la Univeresidad del Zulia. Su presentación fue exitosa y tenemos ahora una nueva Master...Felicitaciones, Jaqueline.
Nuevos licenciados
Los días 2 y 3 de diciembre defendieron muy satisfactoriamente sus trabajos de tesis para optar al título de Licenciado en física los compañeros Zorangel Sanchez y Miguel Angel Velasquez. Nuestro grupo les felicita y nos sentimos orgullosos de Uds. ¡¡¡Disfruten sus merecidads vacaciones y les esperamos!!!!!!

El 18 de Octubre Andrea Villa defendió su tesis en la Universidad del Zulia y recibió una "Mención Publicación". Gracias Andrea por ese regalo. Y felicitaciones por el título que te otorgaron como Licenciada en Física el martes 3 de Diciembre. 

Nuestro grupo de investigación forma parte del Laboratorio de Dispersiones e Interfases del Centro de Estudios Interdisciplinarios de la Física. Nuestro interés científico se centra en aspectos fundamentales de fenómenos que ocurren en sistemas coloidales, más específicamente, en dispersiones fluido/fluido. En este sentido, utilizamos herramientas numéricas, teóricas y experimentales que nos permitan tener una visión completa de la llamada realidad.


El pasado 29 y 30 de Abril se celebró el Nanotaller Colloides 2013 en la UNEXPO. Una nota de Prensa NANOTALLER 2013



Recientemente, fué publicado el libro:Topics in Colloidal Aggregation and Interfacial Phenomena, By Research Singpost. Una nota de prensa aqui





Despite the vast presence of colloids in human life since the fabrication of the first paints, some medicaments and foods, it was only in the last one hundred years that the systematic study of those systems started. Today, the interest in the understanding, fabrication, and manipulation of colloids has allowed the generation of new applications and technologies such as drug delivery, nanoparticles, microfluidics, new pesticides, oil recovery, and a much longer list. The birth of what we call today colloidal science is the result of an interdisciplinary effort where physics, chemistry, engineering, biology, mathematics, and computation participate actively. Colloids represent the benchmark for many advances in the understanding of nature. Since the theoretical predictions of Einstein of Brownian motion as an evidence of the existence of molecules almost a century ago, to the development of non-equilibrium statistical mechanics, colloids are the perfect systems to test our ability of predicting and translating that knowledge into important applications.
Depending on the nature of the phases involved i. e., gas, liquid or solid particles suspended into a fluid phase, different mechanisms act in order to phase separate. In the case of solids, the aggregation and eventual formation of clusters of particles is the leading mechanism. If the particles are fluid (gas or liquid), they can coalesce as a consequence of the rupture of the separating film produced during the aggregation. Also, for nanometric sized systems, Ostwald ripening can occur. The action of gravity becomes important as the particles (aggregates) increase the size forcing the phases to separate by differences in their densities. In all cases, the behavior is dominated by the surface interactions between the particles and is determined by the physicochemical conditions of the system: salt concentration, viscosity of the involved phases, presence of surfactant, volume fraction, temperature, etc.  To some extent, the effect of each parameter on the kinetic is
well understood. However, the time dependence and the simultaneous occurrence of the above mentioned phenomena make difficult to predict precisely the actual dynamics of the system. For these reasons, it is clear that the behavior of colloids and the interfacial properties of the forming particles are closely related.
This volume on “Topics in Colloidal Aggregation and Interfacial Phenomena" published as a special review book by Research Signpost contains contributions of the main research groups working on this subject during the last years in Venezuela, and also contributions of international research groups that have participated in the development of these investigations. In this sense, we have tried to make a balance between the fundamental aspects and the possible applications of that knowledge to problems such as prediction of colloidal stability, formulation of systems with the desired properties, oil recovery, and others.
We have organized this volume from fundamental aspects of colloidal aggregation to frontiers topics in microfluidics and tribology. Chapter one introduces important concepts in aggregation, characterization, and phase transitions of solid particles. In chapter two, the synthesis of nanoemulsion by means of low energy techniques, using the chemical properties of the phases involved, and the occurrence of Ostwald –ripening as the leading mechanism of phase separation is explained. Also, the application of nanoemulsions as nanoreactors is reviewed. Chapter three focuses on the thermodynamic aspects of the fluid/liquid interfase based on a mesoscopic description where the interfacial phenomena are explained in terms of an elastic field. Besides, some thermodynamic treatments commonly used to study binary liquid mixtures are discussed. In chapter four the results of the application of two experimental techniques to study the formation of molecular aggregates at the interface in a ternary system are shown and discussed. In both cases, it is observed well defined peaks in the interfacial entropy. In chapter five, the application of formulation techniques to obtain ultralow surface tensions are applied to the particular case of oil recovery, a very important issue in our country. Chapter six is devoted to explain the partitioning of some type of surfactants depending on the physicochemical variables that characterize the system showing experimental results and the theoretical understanding. In the chapter seven, the surface viscoelastic properties are explained in detail and new insights in the theoretical description are shown based on the experimental results. Chapter eight deals with the deformation of emulsion droplets during collision showing a new numerical approach developed to study the dynamics of nanofilms. The deformation of large droplets is treated in chapter nine based on smoothed particle hydrodynamics (SPH) approach that allows studying different situations. Chapter ten focuses on the problem of the coalescence of a droplet pushed against a planar interface using Emulsion Stability Simulations. Chapter eleven resumes the use of microfluidics as a new experimental tool to obtain emulsions under well controlled conditions and its impact in the understanding and novel applications of liquid/liquid dispersions. The final chapter twelve the recent advances in the understanding of the complex phenomenon of lubrication at molecular level is discussed and  illustrate the complexity of the subject and suggest pathways for the smart design of multi-component water-based boundary lubricants.
Finally, we want to thank to our institutions, especially to IVIC and INTEVEP, for their funding support. Also we want to express our gratitude to all the contributors to this volume for their willingness and patience in the communication with the editors, and to Professor S.G. Pandalai for his kind invitation and stimulus to work in the elaboration of the present volume.    





The problems motivating my research interest are predominantly ascribed to colloidal science and interfacial phenomena of soft matter.  Specifically, my ongoing and future research focuses on dissipation mechanisms of soft particles in fluid media, dynamics of droplet deformation, mass variable systems, non-equilibrium statistical mechanics, and emulsion stability. These problems require a multidisciplinary approach not only due to the multiple basic aspects related to the complex phenomena occurring in those systems but for the wide spectrum of applications ranging from drug delivery, foods, and cosmetics to, more recently, nanotechnology.
Students
  1. Gieberth Rodriguez (Graduate Student)
  2. Jaqueline Fernandez (Graduate Student)
  3. Yanitza Trosel (Graduate Student)
  4. Julio Heras (Graduate Student)
  5. Yhan Williams (Graduate Student)
  6. Andrea Villa (Graduate Student)
  7. Miguel Angel Velasquez (Graduate Student)
  8. Nelmary Roa (Graduate Student)
  9. Reina Camacho (Currently at Laboratoire de Physique Corpusculaire)
  10. Zorangel Sanchez (Graduate Student)
  11. Yunexy Castellanos (Undergraduate Student)

ESTUDIANTES INTERESADOS EN TESIS DE PRE Y POSTGRADO, FAVOR ENVIAR CV AL CORREO ELECTRÓNICO jhoantoro@yahoo.com.ar

Collaborators:
  1. Aileen Lozsan (IVIC)
  2. Aly Castellanos (IVIC)
  3. Angel G. Muñoz (Columbia University)
  4.  Antonio Puertas (Universidad de Almeria)
  5. Carlo Guerrero (LUZ)
  6. Dimiter Petsev (University of New Mexico)
  7. Germán Urbina-Villalba (IVIC)
  8. Frank van Swol (Sandia National Labs)
  9. Hector Rodriguez (IVIC)
  10. Máximo García Sucre (IVIC)
  11. Michael Loewemberg (Yale University)
  12. Plamen Attanasov (University of New Mexico)


Información adicional y eventos de interés:

Los días 24 y 25 de Mayo del 2012 se realizó el NANOTALLER 2012 IVIC-UNEFM  en la cuidad de Pto. Fijo, Venezuela. Una nota de prensa aquí
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Jhoan Toro-Mendoza,
5 may. 2013 11:14
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