Novel granular bentonite-carbon sorbents: textural characterization, adsorption-desorption isotherm, kinetics, and cost estimation.

This research focuses on the synthesis of novel low-cost granular sorbents based on bentonite clay of the Navbahor deposit, dust fraction of Angren brown coal, and agricultural wastes such as straw and sawdust to meet the internal needs of the Republic of Uzbekistan. The impact of the initial mixture ingredients on the structural and textural properties of bentonite-coal sorbents (BCSs) has been studied using X-ray diffraction, Raman spectroscopy, Fourier-transform infrared spectroscopy, optical microscopy, and nitrogen adsorption-desorption analysis. For determining the sorption capacity of BCSs, a standard model substance methylene blue (MB), was applied.

Nanosilica modified by polydimethylsiloxane depolymerized and chemically bound to nanoparticles or physically bound to unmodified or modified surfaces: Structure and interfacial phenomena.

Three polydimethylsiloxanes (PDMS200, PDMS1000, and PDMS12500 with numbers showing the viscosity values dependent on the molecular weight) were used for adsorption (14-95 wt% PDMS) onto unmodified and PDMS-modified (16.7 wt% PDMS using dimethyl carbonate (DMC) as a siloxane bond breaking reagent) nanosilica A-300. The materials were studied using microscopy, infrared spectroscopy, thermodesorption, calorimetry, ethanol and water/ethanol evaporation, nitrogen adsorption-desorption, and quantum chemical methods.

Bonding of doxorubicin to nanosilica and human serum albumin in various media.

Interaction of doxorubicin hydrochloride (DOX) (anti-cancer drug) with hydro-compacted nanosilica A-300 (cA-300) alone or cA-300/human serum albumin (HSA) at a small content of water (h = 0.4 g per gram of dry silica) in different dispersion media (air, chloroform, and chloroform/trifluoroacetic acid) was analyzed using low-temperature H NMR spectroscopy, NMR cryoporometry and quantum chemistry to elucidate specific changes in the interfacial layers. Initial (bulk density ρ ≈ 0.

Relaxation phenomena in poly(vinyl alcohol)/fumed silica affected by interfacial water.

Interaction of poly(vinyl alcohol) (PVA) with fumed silica was investigated in the gas phase and aqueous media using adsorption, broadband dielectric relaxation spectroscopy (DRS), thermally stimulated depolarization current (TSDC), infrared spectroscopy, thermal analysis, and one-pass temperature-programmed desorption (OPTPD) mass-spectrometry (MS) methods. PVA monolayer formation leads to certain textural changes in the system (after suspension and drying) because of strong hydrogen bonding of the polymer molecules to silica nanoparticles preventing strong interaction between silica particles themselves. This strong interaction promotes associative desorption of water molecules at lower temperatures than in the case of silica alone.

TSDC spectroscopy of relaxational and interfacial phenomena.

Applications of thermally stimulated depolarisation current (TSDC) technique to a variety of systems with different dispersion phases such as disperse and porous metal oxides, polymers, liquid crystals, amorphous and crystalline solids, composites, solid solutions, biomacromolecules, cells, tissues, etc. in gaseous or liquid dispersion media are analysed. The effects of dipolar, direct current (dc) and space charge relaxations are linked to the temperature dependent mobility of molecules, their fragments, protons, anions, and electrons and depend on thermal treatment, temperature and field intensity of polarisation, heating rate on depolarisation or cooling rate on polarisation.