表面杂质 meaning in Chinese

surface impurity
surface inclusions

First , it is associated with the prepared conditions of spectral pure graphite electrode ; second , compared with the untreated graphite , the surface functional groups of ? oh and ? cooh on the treated one increased dramatically with hot concentrated h2so4 and the impurities on electrode surface decreased significantly with ultrasonic rinse . a sequence reaction mechanism was proposed for the eis of mn ( ) / mn ( ) on different graphite electrodes . the spectral graphite and the treated one can be suitable for the inert electrode of mn ( ) / mn ( ) cathode
分析原因认为：一方面与光谱纯石墨电极的制备条件有关；另一方面，与未处理石墨电极相比，处理石墨表面含氧官能团? oh 、 ? cooh明显增多，而且超声清洗又使其表面杂质含量减少，并提出了一个反应机理解释mn ( iii ) / mn ( ii )电对在三种石墨电极上阻抗谱的不同，说明光谱纯石墨和处理石墨均可以作为mn ( iii ) / mn ( ii )正极电对的惰性工作电极。