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Macroion adsorption: The crucial role of excluded volume and coions

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 نشر من قبل Ren\\'e Messina
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Rene Messina




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The adsorption of charged colloids (macroions) onto an oppositely charged planar substrate is investigated theoretically. Taking properly into account the finite size of the macroions, unusual behaviors are reported. It is found that the role of the coions (the little salt-ions carrying the same sign of charge as that of the substrate) is crucial to understand the mechanisms involved in the process of macroion adsorption. In particular, the coions can accumulate near the substrates surface and lead to a counter-intuitive {it surface charge amplification}.

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