J. Martínez-mardones - Academia.edu (original) (raw)
Papers by J. Martínez-mardones
The challenges in the present educational reform emphasize the professional character of the teac... more The challenges in the present educational reform emphasize the professional character of the teacher in the planning of classes, execution of activities and evaluation of learning. A set of planned activities is not to a class of science as a pile of thrown bricks is to a house; this is, that if it is not counted on the knowledge of the preconceptions of the students, the daily realities that they face and of the expectations that these have at the time of participating in the science classes, cannot be obtained the proposed objectives. The well-known investigatory method applied to the education of sciences approaches the conceptual contents from practical activities of easy reproduction that are guided in effective form towards the topics to teach. Guides OPPS (Operation Primary Physics Science), of Louisiana University, are excellent examples of the application of this methodology, as much in the material that corresponds to the students as in the material for the guide of the learning activities (call Leader of the class). This international experience, within the framework used of the Plans and Programs of the Ministry of Education of Chile (MINEDUC), is the main axis of this work in which the accomplishment of guides with this methodology considers, approaching contained of a unit of the common plan of physics for third grade of high school.
Physico-chemical thermodynamics of material systems - a review of basic concepts and results, A.F... more Physico-chemical thermodynamics of material systems - a review of basic concepts and results, A.F. Guillermet computational methods for mesoscopic, inhomogeneous plastic deformation, N.M. Ghoniem fingering in thin layer electrodeposition, M.Q. Lopez-Salvans et al pattern formation and surface modification techniques, D. Walgraef a review on the problem of measuring nonlinear damping and the obtainment of intrinsic damping, O.A. Lambri a review of growing interfaces in quenched disordered media, L.A. Braunstein et al path integral approach to nearest neighbour particle distance, A.D. Sanchez et al plastic instabilities and dislocation patterns, D. Walgraef one-dimensional recrystallization, C.H. Worner.
Physica A: Statistical Mechanics and its Applications, 2000
The onset of convection in a binary-viscoelastic Oldroyd-B uid is investigated. The threshold for... more The onset of convection in a binary-viscoelastic Oldroyd-B uid is investigated. The threshold for oscillatory convection is calculated. It is shown that the critical oscillation frequency may di er by several orders of magnitude on varying separation ratio and Deborah number. The results suggest that binary uid aspects may not be discarded when studying thermal convection in polymeric solutions.
Mathematical Biosciences and Engineering, 2007
We study the feasibility of transferring data in an optical device by using a limited number of p... more We study the feasibility of transferring data in an optical device by using a limited number of parallel channels. By applying a spatially localized correcting term to the evolution of a liquid crystal light valve in its spatiotemporal chaotic regime, we are able to restore the dynamics to a specified target pattern. The system is controlled in a finite time. The number and position of pinning points needed to attain control is also investigated.
Journal of Physics: Condensed Matter, 1990
The onset of convection in a viscoelastic fluid that obeys the Jeffreys model is investigated. Tw... more The onset of convection in a viscoelastic fluid that obeys the Jeffreys model is investigated. Two boundary conditions have been considered separately: free-free and rigid-rigid. The role played by the retardation time, characteristic of the Jeffreys model, is emphasised. The threshold values of the parameters (critical Rayleigh number, critical wavenumber, onset frequency, etc.) for stationary and oscillatory convection are obtained.
Journal of Physics: Conference Series, 2008
ABSTRACT In this work we report theoretical and numerical results on convection for a binary magn... more ABSTRACT In this work we report theoretical and numerical results on convection for a binary magnetic mixture under rotation. We focus in the stationary convection for idealized boundary conditions and we obtain explicit expressions of convective thresholds in terms of the control parameters of the system. The effect of the magnetophoresis and Kelvin force are emphasized. Finally, we analyze the stabilizing effect of rotation on instability thresholds for aqueous suspensions.
International Journal of Bifurcation and Chaos, 1994
The convective instabilities in viscoelastic polymeric Oldroyd-B models are studied. First, the n... more The convective instabilities in viscoelastic polymeric Oldroyd-B models are studied. First, the nonlinear analysis of the stationary and oscillatory convection is carried out. Then, in the scope of weak nonlinear analysis, the coefficients of the amplitude equations are evaluated, in order to be in condition to estimate the possible behavior of stationary patterns and also travelling and standing waves. The values of these coefficients are determined by means of analytical and numerical techniques for convection in polymeric fluids.
International Journal of Bifurcation and Chaos, 2010
We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic ... more We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid. We focus on the stationary convection for idealized boundary conditions. We obtain explicit expressions of convective thresholds in terms of the control parameters of the system. Close to bifurcation, the coefficients of the corresponding amplitude equation are determined analytically. The effect of the rheology and Kelvin force are emphasized and, finally, the nature of the bifurcation is discussed.
The European Physical Journal Special Topics, 2013
In this manuscript we report theoretical and numerical results on convection for a magnetic fluid... more In this manuscript we report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid. The viscoelastic properties is given by the Oldroyd model. We impose the lower interface to be rigid, whereas the upper one free which is assumed to be non-deformable and flat. Also, at the upper interface the surface tension is taken to vary linearly with the temperature. Using a spectral method we calculate numerically the convective thresholds for both stationary and oscillatory bifurcation. The effect of the viscoelasticity and the Kelvin force on instability thresholds are emphasized.
The European Physical Journal Special Topics, 2007
In this work we report theoretical and numerical results on convection in a viscoelastic binary m... more In this work we report theoretical and numerical results on convection in a viscoelastic binary mixture under rotation. In particular, we focus in the Maxwelian case of viscoelastic fluid. We obtain explicit expressions for the convective thresholds in terms of the mixture parameters of the system in the case of idealized boundary conditions. We also calculate numerically the convective thresholds for the case of realistic rigid-rigid boundary conditions.
Localized structures can be found in many different (dissipative) driven systems [1], an example ... more Localized structures can be found in many different (dissipative) driven systems [1], an example being stationary and traveling convection structures in the thermal instability of binary fluids. Here, the special localized structure is a convective state between two quiescent, conductive ones, and can been interpreted as a pinning phenomenon close to a stationary sub-critical bifurcation. Generally, localized structures are described by using higher dimensional, complex amplitude or phenomenological prototype (e.g. Swift-Hohenberg) equations or by direct numerical integration of the hydrodynamic equations. Here we show, using the binary mixture convection in porous media as an example, that the analytically derived one-dimensional amplitude equation amended by non-adiabatic (non-resonant) terms important close to convection fronts, well describes localized convection states, in particular the slanted homoclinic bifurcation diagrams.
Journal of Non-Newtonian Fluid Mechanics, 2000
The threshold for oscillatory convection in Rayleigh–Bénard experiments with viscoelastic binary ... more The threshold for oscillatory convection in Rayleigh–Bénard experiments with viscoelastic binary fluids is explicitly determined as a function of separation ratio and rheological parameters. In particular, it is shown that the critical oscillation frequency may differ by several orders of magnitude on varying separation ratio and Deborah number. The results suggest that binary fluid aspects may not be discarded when
Physical Review E, 1996
Pattern selection and stability in viscoelastic convection are studied in the framework of amplit... more Pattern selection and stability in viscoelastic convection are studied in the framework of amplitude equations derived in the vicinity of stationary and oscillatory instabilities. The oscillatory instability corresponds to a Hopf bifurcation with broken translational symmetry. When this instability is the first to appear with increasing Rayleigh number, such systems may be described by coupled one-dimensional complex Ginzburg-Landau equations for
Physica A: Statistical Mechanics and its Applications, 2007
In this work we report theoretical and numerical results on convection in a viscoelastic binary m... more In this work we report theoretical and numerical results on convection in a viscoelastic binary mixture under rotation for realistic rigid-rigid boundary conditions. We focus our analysis in the DNA aqueous suspensions. Instability thresholds for oscillatory convection are calculated. Finally, we analyze the stabilizing effect for the onset of convection.
Journal of Magnetism and Magnetic Materials, 2014
We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic ... more We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid under rotation. The viscoelastic properties are given by the Oldroyd model. We obtain explicit expressions for the convective thresholds in terms of the parameters of the system in the case of idealized boundary conditions. We also calculate numerically the convective thresholds for the case of realistic boundary conditions. The effects of the rheology and of the rotation rate on the instability thresholds for a diluted magnetic suspension are emphasized.
Following the insight of P. Kolodner (J. Non-Newtonian Fluid Mech. 75 (1998) 167)on DNA solutions... more Following the insight of P. Kolodner (J. Non-Newtonian Fluid Mech. 75 (1998) 167)on DNA solutions, a study of the Rayleigh-Bénard instability for a binary viscoelastic fluid is presented. We emphasize the role of the relaxation time typical of the Oldroyd-B model for a viscoelastic fluid and the Soret effect characteristic of binary fluids. Critical values of parameters for oscillatory convection are established. The results suggest that the aspect of binary fluids cannot be ignored when studying the convection of polymeric solutions.
Convection in viscoelastic uids may be induced by oscillatory or stationary instabilities. When t... more Convection in viscoelastic uids may be induced by oscillatory or stationary instabilities. When the oscillatory instability appears ÿrst, the system may be described, in its vicinity by coupled Ginzburg-Landau equations. We study the convective and absolute instabilities of the steady states of these equations. We analyze pattern selection and stability in deterministic and stochastic systems and discuss the possibility of noise-induced phase transitions.
Chaos, Solitons & Fractals, 1995
The near-threshold behavior of thermal convection in viscoelastic polymeric Oldroyd-B type fluids... more The near-threshold behavior of thermal convection in viscoelastic polymeric Oldroyd-B type fluids in an infinite horizontal layel" heated from below is determined for free and conductive boundary conditions, at the upper and lower limiting surfaces. Linear and nonlinear coefficients corresponding to the different bifurcations are evaluated up to third order of the amplitude equation. A rigorous analytical and numerical calculation of the coefficients of the Ginzburg-Landau equation in the Oldroyd-B model convection is presented.
Journal of Magnetism and Magnetic Materials, 2011
We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic ... more We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid. The viscoelastic properties is given by the Oldroyd model. We obtain explicit expressions for the convective thresholds in terms of the parameters of the system in the case of idealized boundary conditions. We also calculate numerically the convective thresholds for the case of realistic boundary conditions. The effect of the Kelvin force and of the rheology on instability thresholds for a diluted suspensions are emphasized.
The challenges in the present educational reform emphasize the professional character of the teac... more The challenges in the present educational reform emphasize the professional character of the teacher in the planning of classes, execution of activities and evaluation of learning. A set of planned activities is not to a class of science as a pile of thrown bricks is to a house; this is, that if it is not counted on the knowledge of the preconceptions of the students, the daily realities that they face and of the expectations that these have at the time of participating in the science classes, cannot be obtained the proposed objectives. The well-known investigatory method applied to the education of sciences approaches the conceptual contents from practical activities of easy reproduction that are guided in effective form towards the topics to teach. Guides OPPS (Operation Primary Physics Science), of Louisiana University, are excellent examples of the application of this methodology, as much in the material that corresponds to the students as in the material for the guide of the learning activities (call Leader of the class). This international experience, within the framework used of the Plans and Programs of the Ministry of Education of Chile (MINEDUC), is the main axis of this work in which the accomplishment of guides with this methodology considers, approaching contained of a unit of the common plan of physics for third grade of high school.
Physico-chemical thermodynamics of material systems - a review of basic concepts and results, A.F... more Physico-chemical thermodynamics of material systems - a review of basic concepts and results, A.F. Guillermet computational methods for mesoscopic, inhomogeneous plastic deformation, N.M. Ghoniem fingering in thin layer electrodeposition, M.Q. Lopez-Salvans et al pattern formation and surface modification techniques, D. Walgraef a review on the problem of measuring nonlinear damping and the obtainment of intrinsic damping, O.A. Lambri a review of growing interfaces in quenched disordered media, L.A. Braunstein et al path integral approach to nearest neighbour particle distance, A.D. Sanchez et al plastic instabilities and dislocation patterns, D. Walgraef one-dimensional recrystallization, C.H. Worner.
Physica A: Statistical Mechanics and its Applications, 2000
The onset of convection in a binary-viscoelastic Oldroyd-B uid is investigated. The threshold for... more The onset of convection in a binary-viscoelastic Oldroyd-B uid is investigated. The threshold for oscillatory convection is calculated. It is shown that the critical oscillation frequency may di er by several orders of magnitude on varying separation ratio and Deborah number. The results suggest that binary uid aspects may not be discarded when studying thermal convection in polymeric solutions.
Mathematical Biosciences and Engineering, 2007
We study the feasibility of transferring data in an optical device by using a limited number of p... more We study the feasibility of transferring data in an optical device by using a limited number of parallel channels. By applying a spatially localized correcting term to the evolution of a liquid crystal light valve in its spatiotemporal chaotic regime, we are able to restore the dynamics to a specified target pattern. The system is controlled in a finite time. The number and position of pinning points needed to attain control is also investigated.
Journal of Physics: Condensed Matter, 1990
The onset of convection in a viscoelastic fluid that obeys the Jeffreys model is investigated. Tw... more The onset of convection in a viscoelastic fluid that obeys the Jeffreys model is investigated. Two boundary conditions have been considered separately: free-free and rigid-rigid. The role played by the retardation time, characteristic of the Jeffreys model, is emphasised. The threshold values of the parameters (critical Rayleigh number, critical wavenumber, onset frequency, etc.) for stationary and oscillatory convection are obtained.
Journal of Physics: Conference Series, 2008
ABSTRACT In this work we report theoretical and numerical results on convection for a binary magn... more ABSTRACT In this work we report theoretical and numerical results on convection for a binary magnetic mixture under rotation. We focus in the stationary convection for idealized boundary conditions and we obtain explicit expressions of convective thresholds in terms of the control parameters of the system. The effect of the magnetophoresis and Kelvin force are emphasized. Finally, we analyze the stabilizing effect of rotation on instability thresholds for aqueous suspensions.
International Journal of Bifurcation and Chaos, 1994
The convective instabilities in viscoelastic polymeric Oldroyd-B models are studied. First, the n... more The convective instabilities in viscoelastic polymeric Oldroyd-B models are studied. First, the nonlinear analysis of the stationary and oscillatory convection is carried out. Then, in the scope of weak nonlinear analysis, the coefficients of the amplitude equations are evaluated, in order to be in condition to estimate the possible behavior of stationary patterns and also travelling and standing waves. The values of these coefficients are determined by means of analytical and numerical techniques for convection in polymeric fluids.
International Journal of Bifurcation and Chaos, 2010
We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic ... more We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid. We focus on the stationary convection for idealized boundary conditions. We obtain explicit expressions of convective thresholds in terms of the control parameters of the system. Close to bifurcation, the coefficients of the corresponding amplitude equation are determined analytically. The effect of the rheology and Kelvin force are emphasized and, finally, the nature of the bifurcation is discussed.
The European Physical Journal Special Topics, 2013
In this manuscript we report theoretical and numerical results on convection for a magnetic fluid... more In this manuscript we report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid. The viscoelastic properties is given by the Oldroyd model. We impose the lower interface to be rigid, whereas the upper one free which is assumed to be non-deformable and flat. Also, at the upper interface the surface tension is taken to vary linearly with the temperature. Using a spectral method we calculate numerically the convective thresholds for both stationary and oscillatory bifurcation. The effect of the viscoelasticity and the Kelvin force on instability thresholds are emphasized.
The European Physical Journal Special Topics, 2007
In this work we report theoretical and numerical results on convection in a viscoelastic binary m... more In this work we report theoretical and numerical results on convection in a viscoelastic binary mixture under rotation. In particular, we focus in the Maxwelian case of viscoelastic fluid. We obtain explicit expressions for the convective thresholds in terms of the mixture parameters of the system in the case of idealized boundary conditions. We also calculate numerically the convective thresholds for the case of realistic rigid-rigid boundary conditions.
Localized structures can be found in many different (dissipative) driven systems [1], an example ... more Localized structures can be found in many different (dissipative) driven systems [1], an example being stationary and traveling convection structures in the thermal instability of binary fluids. Here, the special localized structure is a convective state between two quiescent, conductive ones, and can been interpreted as a pinning phenomenon close to a stationary sub-critical bifurcation. Generally, localized structures are described by using higher dimensional, complex amplitude or phenomenological prototype (e.g. Swift-Hohenberg) equations or by direct numerical integration of the hydrodynamic equations. Here we show, using the binary mixture convection in porous media as an example, that the analytically derived one-dimensional amplitude equation amended by non-adiabatic (non-resonant) terms important close to convection fronts, well describes localized convection states, in particular the slanted homoclinic bifurcation diagrams.
Journal of Non-Newtonian Fluid Mechanics, 2000
The threshold for oscillatory convection in Rayleigh–Bénard experiments with viscoelastic binary ... more The threshold for oscillatory convection in Rayleigh–Bénard experiments with viscoelastic binary fluids is explicitly determined as a function of separation ratio and rheological parameters. In particular, it is shown that the critical oscillation frequency may differ by several orders of magnitude on varying separation ratio and Deborah number. The results suggest that binary fluid aspects may not be discarded when
Physical Review E, 1996
Pattern selection and stability in viscoelastic convection are studied in the framework of amplit... more Pattern selection and stability in viscoelastic convection are studied in the framework of amplitude equations derived in the vicinity of stationary and oscillatory instabilities. The oscillatory instability corresponds to a Hopf bifurcation with broken translational symmetry. When this instability is the first to appear with increasing Rayleigh number, such systems may be described by coupled one-dimensional complex Ginzburg-Landau equations for
Physica A: Statistical Mechanics and its Applications, 2007
In this work we report theoretical and numerical results on convection in a viscoelastic binary m... more In this work we report theoretical and numerical results on convection in a viscoelastic binary mixture under rotation for realistic rigid-rigid boundary conditions. We focus our analysis in the DNA aqueous suspensions. Instability thresholds for oscillatory convection are calculated. Finally, we analyze the stabilizing effect for the onset of convection.
Journal of Magnetism and Magnetic Materials, 2014
We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic ... more We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid under rotation. The viscoelastic properties are given by the Oldroyd model. We obtain explicit expressions for the convective thresholds in terms of the parameters of the system in the case of idealized boundary conditions. We also calculate numerically the convective thresholds for the case of realistic boundary conditions. The effects of the rheology and of the rotation rate on the instability thresholds for a diluted magnetic suspension are emphasized.
Following the insight of P. Kolodner (J. Non-Newtonian Fluid Mech. 75 (1998) 167)on DNA solutions... more Following the insight of P. Kolodner (J. Non-Newtonian Fluid Mech. 75 (1998) 167)on DNA solutions, a study of the Rayleigh-Bénard instability for a binary viscoelastic fluid is presented. We emphasize the role of the relaxation time typical of the Oldroyd-B model for a viscoelastic fluid and the Soret effect characteristic of binary fluids. Critical values of parameters for oscillatory convection are established. The results suggest that the aspect of binary fluids cannot be ignored when studying the convection of polymeric solutions.
Convection in viscoelastic uids may be induced by oscillatory or stationary instabilities. When t... more Convection in viscoelastic uids may be induced by oscillatory or stationary instabilities. When the oscillatory instability appears ÿrst, the system may be described, in its vicinity by coupled Ginzburg-Landau equations. We study the convective and absolute instabilities of the steady states of these equations. We analyze pattern selection and stability in deterministic and stochastic systems and discuss the possibility of noise-induced phase transitions.
Chaos, Solitons & Fractals, 1995
The near-threshold behavior of thermal convection in viscoelastic polymeric Oldroyd-B type fluids... more The near-threshold behavior of thermal convection in viscoelastic polymeric Oldroyd-B type fluids in an infinite horizontal layel" heated from below is determined for free and conductive boundary conditions, at the upper and lower limiting surfaces. Linear and nonlinear coefficients corresponding to the different bifurcations are evaluated up to third order of the amplitude equation. A rigorous analytical and numerical calculation of the coefficients of the Ginzburg-Landau equation in the Oldroyd-B model convection is presented.
Journal of Magnetism and Magnetic Materials, 2011
We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic ... more We report theoretical and numerical results on convection for a magnetic fluid in a viscoelastic carrier liquid. The viscoelastic properties is given by the Oldroyd model. We obtain explicit expressions for the convective thresholds in terms of the parameters of the system in the case of idealized boundary conditions. We also calculate numerically the convective thresholds for the case of realistic boundary conditions. The effect of the Kelvin force and of the rheology on instability thresholds for a diluted suspensions are emphasized.