Depletion assembly process

The physical properties of most nanomaterials are a manifestation of several types of interatomic, intramolecular, and intermolecular interactions, which can be either cooperative or competitive [17-21]. As a result, the magnitude of each interaction term in the nanomaterial of interest is either enhanced or depleted. In particular, judicious combination of various types of intermolecular interactions would lead to self-assembly process of given molecular systems including selfsynthesis, which would result in ideal molecular engineering process toward smart self-engineered functional molecular systems and nanomaterials. 

Clearly, our results for adhesion of lipid bilayers in fibrinogen and albumin solutions are consistent with the (non-adsorption) depletion type of assembly process. This deduction is based on (i) the null observation that no fiuorescently labelled material was detected in the gap between bilayers, (ii) the continuous increase of the free energy potential with concentration even for fairly large volume fractions, and (iii) the transfer of adherent vesicle pairs with subsequent separation which showed that adhesion energy depended only on the composition of the medium exterior to the gap but not the gap composition. Similar results have been obtained for adhesion of lipid oilayers in solutions of high molecular weight dextran polymers (Figure 4, J ). Hence, we have chosen to carefully examine (non-adsorption) depletion-based theories in conjunction with these experiments. 

Self-assembly can be described as the process of force balance (Lee, 2008). The basic building blocks of a material, regardless of the type and size, experience relatively weak noncovalent forces which cumulatively create major interactions (Lee, 2012). These noncovalent forces include electrostatic, hydrophobic, hydrogen bonding, van der W aals interactions, aromatic stacking, metal coordination, depletion force, solvation/hydration forces, and steric interaction (Mendes et al., 2013 Lee, 2012). In some rare circumstances strong bonds such as covalent, ionic, and coordination bonds are involved in self-assembly in addition to the weaker noncovalent forces (Lee, 2012). 

Melt and dilute. The spent fuel is melted and diluted with depleted uranium. This process was developed at the Savannah River Technology Center (SRTC), USA, and involves melting of the entire spent fuel assembly, diluting the uranium alloy with depleted uranium for isotopic dilution and aluminium for eutectic formation. 

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