We report the temporal stability of the dispersion of single-wall carbon nanotubes in a binary solvent “water + glycerol” having eutectic composition (ca. 67% wt.) with sodium dodecylbenzene sulfonate as a dispersant. The system procures good temporal and thermal stability: its absorption spectra demonstrate no changes during one-year storage with temperature spanning −40 to +40 °C. The system provides non-linear optical power limiting of the incident laser radiation (532 nm) in a one-shot and pulse-periodic regimes of its applying.

This work gives data on the stability of dispersions of single wall carbon nanotubes stabilized by sodium dodecylbenzenesulfonate in binary polar solvents ''water þ antifreeze'' (glycerol, polyethyleneglycole) with eutectic compositions. The absorption spectra of the suspensions demonstrate no changes during 1-year storage with temperature spanning from À40 to þ40 8C. The systems provide relevant optical power limiting properties, the one with glycerol showing good resistance to optical bleaching effects. We also demonstrate that aqueous dispersions of nanotubes exhibit considerable enhancement of optical limiting parameters alongside an increase of the bundled material populace.

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The induced smectic A phase which appears in binary liquid crystalline systems has been investigated. Phase diagrams, clearing enthalpies, heat capacities and mixing enthalpies of two binary mixtures of a terminal polar component and of a weakly polar one are presented. The influence of the alkyl chain length, steric and EDA-type interactions on the formation of induced smectic A phase are discussed.Die induzierte smektische A Phase, die in binlren flussig-kristallinen Systemen auftritt, wurde untersucht. Phasendiagramme, Klarenthalpien, Warmekapazitaten und Mischungsenthalpien von zwei biniiren Mischungen einer polaren mit einer schwachen polaren Komponente werden vorgestellt. Der EinfluB der Alkylkettenlinge, der sterischen und EDA-Wechselwirkung auf die Bildung induzierter smektischer A Phasen wird diskutiert.

The molecular-statistical model of a fluid composed of rectangular parallelepipeds, that is continuous in translations and discrete in orientation distribution, is employed in calculations relating to regions corresponding to the stability of uniaxial and biaxial nematic phases in model mixtures of uniaxial rod-like and plate-like particles, interacting via steric repulsion. The calculations are performed taking into account three-particle correlations. It is shown that for fixed overall mole fraction, the value of the configurational Gibbs free energy of a biaxial phase is equal to that of a system with a miscibility gap containing two uniaxial nematic phases, one rich in rod-like molecules and the other in plate-like ones. The results of the present study are compared with those of studies of related model systems.

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