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To select the most effective methods for functionalizing carbon nanotubes and the to compare the ability of a number of biological molecules (plasmid DNA, ATP, deoxyribonucleoside triphosphates, bovine serum albumin, compounds of vitreous humor extract and sodium humate) to interact noncovalently with carbon nanotubes and mediate their dispersion in an aqueous medium was conducted was the aim of research. Properties of carbon nanotubes-biomolecules conjugates were characterized using ultraviolet, visible and near infrared spectroscopy, Raman spectroscopy, transmission electron and atomic force microscopy. Formation of stable aqueous polydisperse colloidal systems of single-walled and multi-walled non-covalently functionalized carbon nanotubes was shown. The appearance of extended functionalization covering consisting of biomolecules on the surface of carbon nanotubes was demonstrated. Changes in morphology and structure of carbon nanotubes, namely shortening and the appearance of defects in sp2-hybridized surface caused by functionalization were revealed. As a result, the range of molecules of biological origin suitable for noncovalent functionalization of carbon nanotubes was chosen, with correspondence to the specific use in plant biotechnology and the properties of formed complexes were characterized.

It was found that the high decomposition temperature of amorphous Al(OH)3 makes it possible to sinter corundum ceramics directly from aluminum hydroxide, bypassing the stage of its preliminary thermal dehydration. Using the cold isostatic pressing method at 200, 600, and 1000 MPa, compacts with densities of 62, 69, and 79% of the theoretical value were obtained. The temperature dependence of the shrinkage of amorphous Al(OH)3 compacts was studied as a function of the cold isostatic pressing pressure. An area of intense shrinkage was discovered in the range 1050 – 1150°C, which coincides with both the temperature of complete decomposition of amorphous Al(OH)3 and the transition γ → α-Al2O3. [ABSTRACT FROM AUTHOR]

It was shown that Ag(or Ag2O)–ZrO2–Y2O3 formation occurs due to the complex process of decomposition and structure transformation of oxide materials and Ag-complexes. Differences in the decomposition temperatures of Ag-complexes, in particular, and their melting temperatures, and the transformation of ZrO2–Y2O3 NPs morphology leads to the creation of composite structure of two types: an Ag–NPs/zirconia matrix and zirconia core/Ag-shell. It was shown that for these composites the temperature is an effective approach for controlling the NPs sizes for both components (Ag clusters and zirconia NPs), the defectiveness of the complex oxide and their optical properties, in particular the photosensitive to visible irradiation range. [ABSTRACT FROM AUTHOR]

Using the methods of transmission electron microscopy, X-ray structure analysis and thermal differential analysis, it has been discovered that the pulsed magnetic field (PMF) intensifies homogeneous crystallization in LaBGeO5-glass system, promotes homogenization of crystalline phase distribution inside the bulk of glass matrix. A possibility of obtaining the volume nanostructured state in LaBGeO5-glass due to application of PMF has been suggested and experimentally grounded. [ABSTRACT FROM AUTHOR]

This paper represents the rheology of screen printing pastes based on BaTiO3 nanopowder. It is found that the pastes are shear thickened fluids with subsequent shear thinning under high shear rates. Different concentrations of plasticizer in organic binder lead to various conformations of ethyl cellulose molecules that influence the type of adsorption between polymer molecules and nanoparticles. The flow loop shows intervals of shear rate corresponding to rheopexy, pseudoplasticity and thixo - tropy. The appearance of rheopexy indicates that the added amount of plasticizer may be insufficient to bind the majority of free functional groups of the polymer and the remaining groups are bound with BaTiO3 nanoparticles forming a strong structural network. But in the case of pseudoplastic structures, the polymer molecule exists in the conformation where almost all free functional groups are bound with the nanoparticle surfaces. The pseudoplastic properties of the system are caused by the structural polymer-polymer links. SEM and optical profilometry of the obtained films shows that plasticization lead to the formation of thin (less than 1 μm) smooth (Ra is equal to the size of individual BaTiO3 nanoparticle) prints