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MA Yu-Qiang

Bio: MA Yu-Qiang is an academic researcher. The author has contributed to research in topics: Phase transition. The author has an hindex of 1, co-authored 1 publications receiving 7 citations.

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TL;DR: In this article, the effect of coadsorption of CO and O2 on the Ziff-Gulari-Barshad surface catalytic reaction system is studied by Monte Carlo simulation.
Abstract: The effect of the coadsorption of CO and O2 on the Ziff-Gulari-Barshad surface catalytic reaction system is studied by Monte Carlo simulation. The coadsorption of both species adds an extra reaction step to the classical Ziff-Gulari-Barshad model. It is shown that the second-order phase transition from the reactive state to the O-passivated state in the Ziff-Gulari-Barshad model is eliminated, and the production rate of CO2 increases linearly along the fraction yco of CO in gas phase when it is low, in agreement with experimental results. We also find that the increase of the probability of the coadsorption leads to the decrease of the critical value of yco of the discontinuous phase transition to the CO-passivated state.

7 citations


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TL;DR: In this paper, a monomer-dimer model with repulsive interactions between the same species in one dimension was studied and the model exhibits a continuous transition from a reactive phase to an inactive phase with two equivalent absorbing states.
Abstract: We study a monomer-dimer model with repulsive interactions between the same species in one dimension. With infinitely strong interactions the model exhibits a continuous transition from a reactive phase to an inactive phase with two equivalent absorbing states. Monte Carlo simulations show that the critical behavior is different from the conventional directed percolation universality class but seems to be consistent with that of the models with the mass conservation of modulo 2.

51 citations

Journal ArticleDOI
TL;DR: In this paper, the static critical exponents were determined accurately which were in excellent agreement with those of directed percolation universality class, which is the class of this paper.
Abstract: A simple irreversible surface reaction model first introduced by Ziff, Gulari and Barshad has been studied using Monte Carlo simulation. We determine the static critical exponents accurately which are in excellent agreement with those of directed percolation universality class.

1 citations

Journal ArticleDOI
TL;DR: In this paper, the Eley-Rideal (ER) mechanism was combined with the Langmuir-Hinshelwood (LH) thermal mechanism to obtain a single phase transition between active states and poisoned states.
Abstract: Interactions among the reacting species NO, CO and O2 on metal catalytic surfaces are studied by means of Monte Carlo simulation using the Eley-Rideal (ER) mechanism. The study of this three-component system is important for understanding of the reaction kinetics by varying the relative ratios of the reactants. It is found that contrary to the conventional Langmuir-Hinshelwood (LH) thermal mechanism in which two irreversible phase transitions are obtained between active states and poisoned states, a single phase transition is observed when the ER mechanism is combined with the LH mechanism. The phase diagrams of the surface coverage and the steady state production of CO2, N2 and N2 O are evaluated as a function of the partial pressures of the reactants in the gas phase. The continuous production of CO2 starts as soon as the CO pressure is switched on and the second order phase transition at the first critical point is eliminated, which is in agreement with the experimental findings.

1 citations

Journal ArticleDOI
TL;DR: In this article, the effect of precursor motion on the phase diagram of the system is also studied, where the precursor motion of CO molecules is considered only on the surface of a body-centred cubic (bcc) lattice.
Abstract: The CO–NO catalytic reaction on body-centred cubic (bcc) lattice is studied by Monte Carlo simulation. The simple Langmuir–Hinshelwood (LH) mechanism yields a steady reactive window, which is separated by continuous and discontinuous irreversible phase transitions. The effect of precursor mechanism on the phase diagram of the system is also studied. According to this mechanism, the precursor motion of CO molecules is considered only on the surface of bcc lattice. Some interesting observations are reported.

1 citations

Journal ArticleDOI
TL;DR: In this paper, a lattice gas model for the A2+B2→2AB reaction system was studied by Monte Carlo simulation in a two-dimensional triangular lattice surface and the critical behaviour was shown to belong to the robust directed percolation (DP) universality class.
Abstract: A lattice gas model for the A2+B2→2AB reaction system was studied by Monte Carlo simulation in a two-dimensional triangular lattice surface [Phys. Rev. E 69 (2004) 046114]. In the model, a reactive window appears and the system exhibits a continuous phase transition to an `A+vacancy' covered state with infinitely many absorbing states. The critical behaviour was shown to belong to the robust directed percolation (DP) universality class. In this study, we find that as the particle A diffusion is considered, the infinitely many absorbing states for the continuous phase transition change into only two: one is that in which all sites are occupied by particle A and the other is that in which there is only one vacant site and other sites are occupied by particle A. Furthermore, a parity conserving character appears in the system when the particle A diffusion is included. It is found that the critical behaviour of the continuous phase transition changes from the DP class into the pair contact process with diffusion model (PCPD) class and the parity conserving character has no influence on the critical behaviour in the model.

1 citations