Publications by authors named "K N Ustinovich"
A chromatography-like propagation of water through the material bed was observed while performing supercritical fluid extraction of aroma plants having high moisture content. While parts of raw material bed placed at the inlet of the extraction vessel get dried after appropriate extraction time, the parts closer to the outlet not only stay wet but, in fact, gain more moisture than initial raw material. Presumably, water and other extractables with limited solubility in supercritical CO, get re-adsorbed onto the plant material surface along the extraction column and then desorbed further on.
View Article and Find Full Text PDFAn approach for polymer-carbon nanotube (CNT) composite preparation is proposed based on a two-step supercritical fluid treatment. The first step, rapid expansion of a suspension (RESS) of CNTs in supercritical carbon dioxide, is used to de-bundle CNTs in order to simplify their mixing with polymer in solution. The ability of RESS pre-treatment to de-bundle CNTs and to cause significant bulk volume expansion is demonstrated.
View Article and Find Full Text PDF[Features of impedance audiometry in children of the first months of life after acute otitis media].
Vestn Otorinolaringol
July 2021
The features of impedance audiometry with a 226 Hz probe frequency in newborns and children in the first months of life after acute otitis media were analyzed. The age dynamics of tympanograms in children in the first year of life is determined.
View Article and Find Full Text PDFArticle Synopsis
- The study explored how effective carbon nanotubes (CNTs) can be deagglomerated using rapid expansion of supercritical suspensions (RESS) in nitrogen and carbon dioxide.
- Two different deagglomeration mechanisms were identified for each fluid under varying temperatures and pressures.
- The results showed a significant reduction in CNT bundle diameter and an increase in aspect ratio, which were confirmed by ultrasound attenuation spectroscopy and atomic force microscopy.
Article Synopsis
- Ceric hydrogen phosphate gels have a unique fibrous and nearly amorphous structure, making them special materials.
- Researchers used a sol-gel method to create gels that can hold up to 20,000 water molecules for each cerium atom.
- Supercritical processing of these gels led to the development of ultralight aerogels that are noncarbonaceous and have an extremely low density of just 1 mg/cm³.