Kinetics of one-dimensional diffusion-limited reactions in polyacetylene like chain in the presence of particle input and external electric field: computer simulation

AbstractA focused laser beam acts as both a “phototrap”, bleaching fluorophore molecules which diffuse into the beam path, and as a confocal probe, detecting the excited, unbleached fluorophore molecules still present in the trap. With this focused laser beam, we observe anomalous asymptotic rate laws similar to those predicted for a diffusion-controlled elementary trapping reaction, A + T → T, in one and two dimensions. One dimensional diffusion-limited trapping kinetics are approached in capillaries with 10 μm diameters while two dimensional diffusion limited trapping kinetics are observed with unstirred samples having a quasi 2-D geometry. In the presence of stirring, the 2-D samplesexhibit the classical, constant trapping rate over time.

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Diffusion-Limited Cell Dehydration: Analytical and Numerical Solutions for a Planar Model

10.1115/imece1999-0600 ◽

1999 ◽

Author(s):

Alexander V. Kasharin ◽

Jens O. M. Karlsson

Keyword(s):

Analytical Solution ◽

Numerical Solutions ◽

Planar System ◽

One Dimensional ◽

Diffusion Limited ◽

Dimensional Diffusion ◽

Constant Diffusivity ◽

A Cell ◽

Cell Dehydration ◽

The One

Abstract The process of diffusion-limited cell dehydration is modeled for a planar system by writing the one-dimensional diffusion-equation for a cell with moving, semipermeable boundaries. For the simplifying case of isothermal dehydration with constant diffusivity, an approximate analytical solution is obtained by linearizing the governing partial differential equations. The general problem must be solved numerically. The Forward Time Center Space (FTCS) and Crank-Nicholson differencing schemes are implemented, and evaluated by comparison with the analytical solution. Putative stability criteria for the two algorithms are proposed based on numerical experiments, and the Crank-Nicholson method is shown to be accurate for a mesh with as few as six nodes.

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Initial Kinetics of ATP-Synthesis and of Conformational Changes in the Chloroplast ATPase Studied by External Electric Field Pulses

Annual Meeting of the Deutsche Gesellschaft für Biophysik ◽

10.1007/978-3-642-51881-2_70 ◽

1979 ◽

pp. 72-72 ◽

Cited By ~ 1

Author(s):

E. Schlodder ◽

H. T. Witt

Keyword(s):

Electric Field ◽

External Electric Field ◽

Conformational Changes ◽

Atp Synthesis ◽

Kinetics Of

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Anomalous Kinetics of Depletion Zone Growth with One-Dimensional Geometry: Photobleaching Experiments and Simulations

MRS Proceedings ◽

10.1557/proc-790-p7.15 ◽

2003 ◽

Vol 790 ◽

Author(s):

Hailin Peng ◽

Sung Hyun Park ◽

Haim Taitelbaum ◽

Raoul Kopelman

Keyword(s):

Main Parameter ◽

Depletion Zone ◽

Previous Theory ◽

Slow Increase ◽

One Dimensional ◽

Diffusion Limited ◽

Simulation Results ◽

Kinetics Of ◽

Fluorescein Dyes ◽

Zone Growth

ABSTRACTWe studied the kinetics of a diffusion-limited trapping reaction A + T → T in an effective one-dimensional geometry by experiments, supported by simulation calculations. The experiments are based on the photobleaching reaction of fluorescein dyes. The main parameter of interest is the θ-distance, which is related to the expansion of the depletion zone and can be measured directly from experiment. We found that θ-distance scales with t1/2 asymptotically, as predicted by previous theory. In addition, we found that the θ-distance increases faster than t1/2 inside the trap at early times, which has not been explored previously. Furthermore, there is a third, intermediate regime, with a slow increase of slope. Our experimental results are consistent with our simulation results.

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