Page 10 - Korniy_dyser
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                  the importance of not only plastic, but also elastic deformation for the corrosion
                  and corrosive-mechanical degradation of aluminium alloys.


                         Also  for  the  first  time  we  have  provided  the  theoretical  basis  for  the
                  inhibitory  ability  of  surface-active  rhamnolipid  biocomplex  on  the  aluminium


                  alloys  under  the  conditions  of  constant  formation  of  new  surfaces,  i.e.,  during
                  tribocorrosion. In addition, we have unraveled the formation of stable complexes


                  between  rhamnolipids  and  aluminium  ions,  which  could  form  a  barrier  organic

                  layer on the metal surface thereby preventing its corrosive dissolution. Moreover,

                  we  have  predicted  the  mechanism  of  the  synergic  interaction  between  the

                  rhamnolipid and calcium and zinc phosphates, which improves their solubility and
                                     3-
                  formation of PO 4  anions thus reinforcing the inhibitory effect.

                         By  calculating  the  structure  along  with  electronic  and  energetic

                  characteristics  of  clinoptilolite  (zeolite)  clusters,  we  have  established  the

                  reinforcement  effect  on  activity  of  the  electron-donor  centers  of  these  clusters

                  modified with calcium ions and also on their ability to absorb hydrogen ions. This

                  explains the experimental data suggesting higher anti-corrosive properties of Ca-

                  modified zeolite as compared to Zn-modified zeolite on the aluminium alloys.

                         Using  quantum-chemical  methods  we  have  determined  the  precise

                  mechanism  of  how  the  components  of  the  corrosive  environment  influence  the

                  contacting surfaces of metallic clusters. It has been established that the change in

                  the  energy  of  the  contact  interactions  in  metallic  clusters  in  the  environment

                  happens due to the redistribution of the surface charge or electron density in the

                  energetically  favorable  three-centred  and  bridged  configurations  of  clusters,  in

                  which the environmental components are absorb. This data confirms the postulates

                  of the theory of structural-thermal surface activation during tribocorrosion.

                         We have proposed a novel method of theoretical evaluation and prediction

                  of  the  corrosive-morphological  stability  of  binary  metal  nanoparticles  using,  on

                  one hand, the density functional method which takes into account the correlation

                  effects  important  for  transition  metals,  but  on  the  other  hand,  accounting  for

                  structure  relaxation  of  model  nanoclusters  by  molecular-dynamic  method.  The
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