Bogorodskii S.E.,Russian Academy of Sciences |
Zarkhina T.S.,RAS Semenov Institute of Chemical Physics |
Kuznetsov E.V.,Karpov Scientific Research Physicochemical Institute |
Minaeva S.A.,Russian Academy of Sciences |
And 3 more authors.
Russian Journal of Physical Chemistry B | Year: 2014
The microstructure and properties of amorphous D,L-polylactide subjected to different treatments in supercritical carbon dioxide (SC-CO2) were investigated. Atomic force microscopy analysis demonstrated that plasticization and subsequent foaming of the polymer in SC-CO2 leads to significant changes in its internal structure, which are caused by the rearrangement of the supramolecular structure of polylactic acid. The formation of micro and meso pores and an accompanying increase of polylactide void volume are directly related to the destruction of polymer initial intermolecular bonds during the release of SC-CO2. These changes facilitate the formation of thermodynamically more stable conformations, which is manifested in a significant (1.7–5.0-fold) increase of the values of exothermic effects registered by differential scanning calorimetry in the temperature range from −30 to −10°C and near 30–40°C. © 2014, Pleiades Publishing, Ltd. Source
Grishin M.V.,RAS Semenov Institute of Chemical Physics |
Gatin A.K.,RAS Semenov Institute of Chemical Physics |
Dokhlikova N.V.,RAS Semenov Institute of Chemical Physics |
Kirsankin A.A.,RAS Semenov Institute of Chemical Physics |
And 4 more authors.
Nanotechnologies in Russia | Year: 2014
The properties of single electronic traps in nanoparticles of tin and zinc oxides have been determined. These traps are responsible for the change in the concentration of electrons in the conduction band of gas sensors based on nanostructured films of tin and zinc oxides. Positions of the energy levels and characteristic times of the depletion for electronic traps formed by oxygen vacancies in zinc oxide and oxygen atoms adsorbed on the tin oxide have been established. © 2014 Pleiades Publishing, Ltd. Source
Kupriyanov L.Y.,Karpov Scientific Research Physicochemical Institute |
Roginskaya Y.E.,Karpov Scientific Research Physicochemical Institute |
Kozlova N.V.,Karpov Scientific Research Physicochemical Institute |
Politova E.D.,Karpov Scientific Research Physicochemical Institute |
And 2 more authors.
Nanotechnologies in Russia | Year: 2011
Nanocomposite silicon-carbon thin films have been obtained using the layer-by-layer magnetron sputtering technique. The film thickness amounts to 110-470 nm. They possess a layered nanostructure formed by silicon and carbon layers of 7-10 nm each. X-ray diffraction investigations have shown the presence of a silicon carbide crystalline phase formed at layer interfaces of the films. The mirror-reflection spectra in the range of 200-2500 nm contain a number of maxima which can be attributed to the absorption spectra of amorphous silicon, amorphous carbon, and disorderred silicon carbide. Peculiarities of the IR absorption spectra indicate that graphene phases of low dimensionality can be formed in the region of silicon- and carbon-layer junctions. It is suggested that the films under study can be considered a promising basis for the development of lithium-battery electrodes with improved characteristics. © 2011 Pleiades Publishing, Ltd. Source