Active diffusion Limited reactions

• 作 者: Fabio Marchesoni
• 机 构: UniversityofCamerino,ItalyandTongjiUniversity,Shanghai,PRChina
• 出 处: 第十一届全国软物质与生命物质物理学术会议
• 发表日期: 2018年11期

　　Artificial active swimmer,like Janus particles,can be used to deliver reactants to targeted space regions where one wants a given chemical reaction to take place.In general,one can assume that the reactant delivery rate is much lower than the ensuing chemical reaction rate,which thus can be taken to be instantaneous.This situation describes a diffusion limited reaction(DLR),a topic widely investigated over the last fifty years.In this preliminary report,we discuss the case of the basic reactions A+A → 0 and A+B → 0,where,in contrast with the earlier literature,reactant A is carried by an active Janus particle,characterized by self-propulsion speed v0 and angular diffusion constant Dr,and reactant B diffuses freely(or possibly carried by a passive colloidal particle).We simulated numerically the time evolution of a large assembly of A and B particles both in d=1 and d=2 dimensions and focused our attention of the time dependence of the residual reactant densities,(t),versus time.We observed that for finite values of the persistence time,Dr-1,of the A particles,(t)decays(much)faster than reported in the DLR literature,with power laws that are peculiar to active DLRs for diverse parameter choices.