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In this paper, we review several aspects of molecular recognition (based on non-covalent binding interactions) occurring between meso-pyridyl substituted tetrapyrrole extra-ligands and chemical dimers of tetrapyrrolic macrocycles containing central Zn ions and spacers of various nature and flexibility. Experimental results obtained by us earlier are analyzed using a novel approach (based on steady-state absorption/fluorescence measurements) for the evaluation of complexation constants K_C for the formation of porphyrin triads. It was found that K_C values [K_C ~ (0.5 – 70) × 10⁶ M^-1] show noticeable dependence on the structural parameters of the interacting subunits as well as on the solvent nature. The same self-assembly approach has been used to attach meso-pyridyl substituted porphyrins to the surface of semiconductor CdSe/ZnS quantum dots (QD). It was comparatively found that in contrast to self-assembled porphyrin triads, the formation of "QD-porphyrin" nanoassemblies takes place in competition with surface stabilizing tri-n-octyl phosphine oxide (TOPO) ligand molecules and attached porphyrin molecules. It manifests in a temporal dynamics of QD photoluminescence caused by ligand exchange, TOPO layer reorganization, QD surface reconstruction, solvent properties. It was shown that the sensitivity of QD surface morphology to attached organic ligands (e.g. porphyrins) provides an opportunity to control the dynamics and pathways of the exciton relaxation in "QD-dye" nanoassemblies by changing the structure and electronic properties of these ligands.

Over the past decade, we have witnessed a stream of research activities on the mechanical and functional properties of graphene- and carbon nanotube-based nanocomposites. In this paper, we outline some of the efforts the present authors have participated along the way. Closely related contributions from the other authors are also introduced. The focus here is on the development of homogenization models for the effective properties of these low-dimensional nanocomposites. A key issue involved is the interface effects which are responsible for many extraordinary properties of the nanocomposites. To pave the way for the presentation of various homogenization models, we first give a general introduction to various categories of interface effects for both mechanical and functional properties. Then, the mechanical properties, involving the complex viscoelastic characteristics and coupled elastoplastic-damage processes, and the functional properties, involving electrical conductivity, dielectric permittivity, thermal conductivity, electromagnetic interference shielding and energy storage, are presented. We conclude with some perspectives on topics that deserve closer investigation in the near future.