Reaction Front Dynamics in Diffusion-Controlled Particle-Antiparticle Annihilation: Experiments and Simulations

We review recent developments in the study of the diffusion reaction system of the type A+B→C in which the reactants are initially separated. We consider the case where the A and B particles are initially placed uniformly in Euclidean space at x>0 and x<0 respectively. We find that whereas for d≥2 a single scaling exponent characterizes the width of the reaction zone, a multiscaling approach is needed to describe the one-dimensional system. We also present analytical and numerical results for the reaction rate on fractals and percolation systems.

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Scaling anomalies in reaction front dynamics of confined systems

Physical Review Letters ◽

10.1103/physrevlett.71.3592 ◽

1993 ◽

Vol 71 (21) ◽

pp. 3592-3595 ◽

Cited By ~ 55

Author(s):

Mariela Araujo ◽

Hernan Larralde ◽

Shlomo Havlin ◽

H. Eugene Stanley

Keyword(s):

Reaction Front ◽

Confined Systems ◽

Front Dynamics

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Study of an A+2B--->C Reaction-Diffusion System with Initially Separated Components

MRS Proceedings ◽

10.1557/proc-366-319 ◽

1994 ◽

Vol 366 ◽

Author(s):

Andrew Yen ◽

Raoul Kopelman

Keyword(s):

Reaction Front ◽

Reaction Rate ◽

Reaction Diffusion ◽

Biological Processes ◽

Local Production ◽

Kinetic Behavior ◽

Acetate Trihydrate ◽

Physical Chemical ◽

Global Reaction ◽

Front Dynamics

ABSTRACTThe presence of a reaction front is a characteristic feature of a variety of physical, chemical and biological processes. A chemical reaction exhibits a front (spatially localized region where concentration of product is non zero), provided the diffusing reactants are separated in space. We study the reaction front dynamics of a termolecular A+2B--->C reaction with initially separated components in a capillary. The reaction tetra+2Ni2+--->1:2 complex is used, where ‘tetra’ is disodium ethyl bis(5-tetrazolylazo) acetate trihydrate. We measure and compare with theory the dynamic quantities that characterize the kinetic behavior of the system: the global reaction rate R(t), the location of the reaction center xf(t), the front's width w(t), and the local production rate R(xf,t). The non-classical nature of this dynamical system is confirmed.

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Experimental Study of An A+B→C Reaction-Diffusion System in a Capillary: Crossovers from Reaction to Diffusion-Limited Regimes

MRS Proceedings ◽

10.1557/proc-290-273 ◽

1992 ◽

Vol 290 ◽

Cited By ~ 4

Author(s):

Yong-Eun Koo ◽

Raoul Kopelman ◽

Andrew Yen ◽

Anna Lin

Keyword(s):

Experimental Study ◽

Reaction Zone ◽

Reaction Front ◽

Reaction Rate ◽

Local Reaction ◽

Reaction Diffusion ◽

Theoretical Studies ◽

Boundary Motion ◽

Diffusion Limited ◽

Front Dynamics

AbstractContinuing work on elementary A+B→C reactions in capillaries, we study the reaction front dynamics of xylanol orange with Cr3+ in an effectively one-dimentional system with initially separated reactants. This reaction, in contrast to previously studied systems, is not strictly in the diffusion limited regime. i.e. the probability of reaction between species is not unity. Anamalous behavior not seen in the diffusion-limited case has been observed experimentally for the reaction rate, boundary motion, reaction zone width, and local reaction rate. The observed behavior is consistent with recent theoretical studies.

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Reaction front dynamics of A + B → C with initially separated reactants

Physica A Statistical Mechanics and its Applications ◽

10.1016/0378-4371(92)90521-q ◽

1992 ◽

Vol 191 (1-4) ◽

pp. 168-171 ◽

Cited By ~ 7

Author(s):

Mariela Araujo ◽

Hernan Larralde ◽

Shlomo Havlin ◽

H.E. Stanely

Keyword(s):

Reaction Front ◽

Front Dynamics

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Auto-Ignition and Reaction Front Dynamics in Mixtures With Temperature and Concentration Stratification

Frontiers in Mechanical Engineering ◽

10.3389/fmech.2020.00068 ◽

2020 ◽

Vol 6 ◽

Cited By ~ 1

Author(s):

Mingyuan Tao ◽

Qi Yang ◽

Patrick Lynch ◽

Peng Zhao

Keyword(s):

Reaction Front ◽

Auto Ignition ◽

Front Dynamics

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Plane front dynamics and pattern formation in diffusion controlled directional solidification of alloys

10.31274/rtd-180813-9844 ◽

2004 ◽

Author(s):

Louise Littles Strutzenberg

Keyword(s):

Pattern Formation ◽

Directional Solidification ◽

Plane Front ◽

Diffusion Controlled ◽

Front Dynamics

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Transport Phenomena and Clot Dissolving Therapy: An Experimental Investigation of Diffusion-Controlled and Permeation-Enhanced Fibrinolysis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648820 ◽

1994 ◽

Vol 72 (01) ◽

pp. 105-112 ◽

Cited By ~ 55

Author(s):

Jung-He Wu ◽

Khalid Siddiqui ◽

Scott L Diamond

Keyword(s):

Experimental Investigation ◽

Whole Blood ◽

Reaction Front ◽

Constant Pressure ◽

Transport Phenomena ◽

Convective Transport ◽

Front Velocity ◽

Fibrin Gels ◽

Diffusion Controlled ◽

Blood Clots

SummaryWe have investigated the effects of diffusive and convective transport on fibrinolysis. Using a constant pressure drop (ΔP/L) from 0 to 3.7 mmHg/cm-clot to drive fluid permeation, various regimes of lytic agents were delivered into fine and coarse fibrin gels (3 mg/ml) and whole blood clots. Using plasmin (1 μM) delivered into pure fibrin or urokinase (1 μM) delivered into glu-plasminogen (2.2 μM)-laden fibrin, the velocity at which a lysis front moved across fibrin was greatly enhanced by increasing ΔP/L. Lysis of fine and coarse fibrin clots by 1 μM plasmin at ΔP/L of 3.67 and 1.835 mmHg/cm-clot, respectively, led to a 12-fold and 16-fold enhancement of the lysis front velocity compared to lysis without pressure-driven permeation. For uPA-me-diated lysis of coarse fibrin at ΔP/L = 3.67 mmHg/cm-clot, the velocity of the lysis front was 25-fold faster than the lysis front velocity measured in the absence of permeation. Similar permeation-enhanced phenomenon was seen for the lysis of whole blood clots. Without permeation, the placement of a lytic agent adjacent to a clot boundary led to a reaction front that moved at a velocity dependent on the concentration of plasmin or uPA used. Overall, these studies suggest that transport phenomena within the clot can play a major role in determining the time needed for reperfusion during fibrinolysis.

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