Interfacial diffusion controlled reactions with time varying absorbing domains

Baldo, M.; Grassi, A.; Lombardo, G. M.; Raudino, A.
November 1996
Journal of Chemical Physics;11/8/1996, Vol. 105 Issue 18, p8404
Academic Journal
A theoretical study for diffusional crossing of a tracer through a membrane, where the size of the adsorbing domain (receptor) is time dependent, is presented. A periodic array of absorbing and reflecting domains at the membrane surface was assumed. This model is described by a time-dependent diffusion equation with mixed boundary conditions, where the boundaries are themselves varying with time. Both analytical and numerical methods were employed in order to calculate the total flux of a tracer across the membrane as a function of the oscillation frequency (ω) and amplitude (ε) of the receptor site. The results show an increase in the absorption rate with frequency, reaching a plateau at very high values of ω. The space and time behavior of the diffusing tracer concentration was analyzed, evidencing dephasing effects at high ω which are common to many nonlinear systems where the dynamic response becomes time independent in the high frequency limit. This approach could be useful in studying the anomalous effect of an oscillating electric field on the membrane permeability. © 1996 American Institute of Physics.


Related Articles

  • Two-photon excitation and photolysis by pulsed laser illumination modelled by spatially non-uniform reactions with simultaneous diffusion. Kiskin, Nikolai I.; Ogden, David // European Biophysics Journal;2002, Vol. 30 Issue 8, p571 

    Provides information on a study which described the relation between light absorption and photolysis rate. Role of diffusion of the cage and intermediates and optimum pulse duration which maximizes yield but minimizes the spatial spread of the products. Models describing photolysis or...

  • Suppression of thermocapillary waves in laser melting of metals and semiconductors. Tokarev, V. N.; Konov, V. I. // Journal of Applied Physics;7/15/1994, Vol. 76 Issue 2, p800 

    Presents a study which examined surface relief stability in the laser melting of materials with relatively high thermal diffusivity and/or relatively high absorption coefficient. Correlation between thermal material processing by laser and surface structure formation; Details on the long pulse...

  • Transient effects in diffusion-controlled absorption by a nonuniform sink of arbitrary constitution. Cichocki, B.; Felderhof, B. U. // Journal of Chemical Physics;1/22/1995, Vol. 102 Issue 4, p1824 

    The time-dependent rate coefficient for absorption of diffusing particles by a nonuniform sink of arbitrary constitution is studied on the basis of the Smoluchowski equation. It is shown that the amplitude of the long-time tail can be expressed in terms of the asymptotic rate coefficient. The...

  • Case-II diffusion in polymers. I. Transient swelling. Hui, C.-Y.; Wu, K.-C.; Lasky, Ronald C.; Kramer, Edward J. // Journal of Applied Physics;6/1/1987, Vol. 61 Issue 11, p5129 

    Presents information on a study which considered the swelling of a polymer glass by sorption of a small molecule penetrant in a regime characterized by so-called case-II diffusion. Methodology of the study; Results and discussion.

  • Analytical description of gas transport across an interface with coupled diffusion in two phases. Huthwelker, Thomas; Peter, Thomas // Journal of Chemical Physics;7/22/1996, Vol. 105 Issue 4, p1661 

    A new analytical formulation of the absorption and desorption of a nonreactive gas across an infinite planar gas–liquid phase boundary is presented. The solution describes diffusive transport in the gas and liquid phases and the kinetic resistance at the phase boundary according to the...

  • Prediction of trapping rates in mixtures of partially absorbing spheres. Kansal, Anuraag R.; Torquato, Salvatore // Journal of Chemical Physics;6/22/2002, Vol. 116 Issue 24, p10589 

    The combined effects of diffusion and reaction in heterogeneous media govern the behavior of a wide variety of physical and biological phenomena, including the consumption of nutrients by cells and the study of magnetic relaxation in tissues. We have considered the so-called "trapping problem,"...

  • The ambipolar diffusion coefficient in silicon: Dependence on excess-carrier concentration and temperature. Rosling, M.; Bleichner, H.; Jonsson, P.; Nordlander, E. // Journal of Applied Physics;9/1/1994, Vol. 76 Issue 5, p2855 

    Presents a detailed experimental analysis of the ambipolar diffusion coefficient in silicon regarding both temperature and injection-level dependence. Measurement of the ambipolar diffusion coefficient; Use of the open-circuit-carrier decay method based on the free-carrier absorption technique.

  • Nonstationary temperature distribution caused by bulk absorption of laser pulse. Gurevich, Yuri; Logvinov, Georgi; de Rivera, Luis Niño; Titov, Oleg // Review of Scientific Instruments;Jan2003, Vol. 74 Issue 1, p441 

    Nonequilibrium temperature is calculated and analyzed in a one-dimensional sample irradiated by a laser rectangular pulse. The general solution is obtained for arbitrary pulse duration compared with the relaxation time of nonstationary thermal diffusion (characteristic time of the problem).

  • Appendix A. Thermal Conversion Factors.  // Monthly Energy Review;Apr99, p145 

    Presents several charts on preliminary thermal conversion factors for 1999.


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics