首页 | 本学科首页   官方微博 | 高级检索  
     检索      

Coherent Resonance for Rate Oscillations During CO Oxidation on Pt(110) Surfaces: Interplay Between Internal and External Noise
作者姓名:马娟  侯中怀  辛厚文
作者单位:中国科学技术大学合肥微尺度物质科学国家实验室,合肥230026;中国科学技术大学合肥微尺度物质科学国家实验室,合肥230026;中国科学技术大学化学物理系,合肥 230026;中国科学技术大学合肥微尺度物质科学国家实验室,合肥230026
基金项目:复杂体系重要非线性化学问题的理论研究
摘    要:用理论和模拟相结合的方法研究了Pt(110)面上CO催化氧化体系中由化学反应随机性所导致的内涨落和参量扰动带来的外涨落对其速率振荡过程的影响,重点考察了内涨落和外涨落的相互作用.在体系的确定性Hopf分岔点附近区域,噪声可以诱导产生随机振荡,其信噪比随噪声强度的变化会出现极大值,即发生了相干共振.运用随机范式理论,研究发现体系的相干共振行为依赖于一\有效噪声",其强度是内涨落和外涨落的加权和.研究结果表明,在内外噪声强度的参数平面内,随机振荡的信噪比呈现屋脊形,太大的内涨落或外涨落条件下相干共振都不能发生.数值模拟的结果和理论分析符合得很好.

关 键 词:涨落,振荡,相干共振,表面催化
收稿时间:2007/12/24 0:00:00
修稿时间:2008/3/25 0:00:00

Coherent Resonance for Rate Oscillations During CO Oxidation on Pt(110) Surfaces: Interplay Between Internal and External Noise
Juan M,Zhong-huai Hou and Hou-wen Xin.Coherent Resonance for Rate Oscillations During CO Oxidation on Pt(110) Surfaces: Interplay Between Internal and External Noise[J].Chinese Journal of Chemical Physics,2008,21(4):339-345.
Authors:Juan M  Zhong-huai Hou and Hou-wen Xin
Institution:Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China;Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China; Hefei National Lab of ysical Science at Microscale, University of Science and Technology of China, Hefei 230026, China;Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
Abstract:Effects of noise on rate oscillations during CO oxidation on Pt(110) surface were investigated, both theo-retically and numerically, by focusing on the interplay of internal noise (IN) due to stochasticity in reaction events, and external noise (EN) resulting from parameter perturbation. The surface is divided into cells of variable size which are assumed to be well mixed, and we consider the behavior inside a single cell. At-tention is paid to parameter regions subthreshold of the deterministic Hopf bifurcation, where noise can induce stochastic oscillations, the signal-to-noise ratio (SNR) of which shows a maximum with the variation of noise intensity, known as coherent resonance (CR). By stochastic normal theory, we show that IN and EN contribute in a weighted additive way to an effective noise that lead to CR, such that SNR shows a ridge shape in the D-1/N plane, where D and 1/N measures the strength of EN and IN, respectively. It is shown that for too large IN (EN), CR behavior with EN (IN) no longer exists. Numerical simulations show good agreements with the theoretical results
Keywords:Fluctuation  Oscillation  Coherent resonance  Surface catalysis
点击此处可从《化学物理学报》浏览原始摘要信息
点击此处可从《化学物理学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号