Influence of Nature of Functional Groups on Interaction of Tetrasubstituted at Lower Rim p-tert-Butyl Thiacalix[4]arenes in 1,3-Alternate Configuration with Model Lipid Membranes

The influence of p-tert-butyl thiacalix[4]arenes (1,3-alternate) functionalized by N-propyl morpholine, N,N-dipropyliden-amine and aminodiacetate fragments on dynamic structure of liposomal membranes prepared from dipalmitoyl phosphatidylcholine was investigated by means of electron spin resonance spin-probe technique and Fourier transform infrared spectroscopy. Nuclear magnetic resonance and transmission electron microscopy techniques were applied to characterize the interacting systems. The obtained results have shown that all studied calixarenes interact with polar domains of bilayer. Depending on functional groups and hydrophobic/hydrophilic properties of calixarenes they can dip into bilayer, locate close to the surface of bilayer or form bridges between positively charged groups of adjacent lipid molecules, thus assisting to disordering or putting in order the lipid molecules. © 2011 Springer-Verlag

Influence of Nature of Functional Groups on Interaction of Tetrasubstituted at Lower Rim p-tert-Butyl Thiacalix[4]arenes in 1,3-Alternate Configuration with Model Lipid Membranes

The influence of p-tert-butyl thiacalix[4]arenes (1,3-alternate) functionalized by N-propyl morpholine, N,N-dipropyliden-amine and aminodiacetate fragments on dynamic structure of liposomal membranes prepared from dipalmitoyl phosphatidylcholine was investigated by means of electron spin resonance spin-probe technique and Fourier transform infrared spectroscopy. Nuclear magnetic resonance and transmission electron microscopy techniques were applied to characterize the interacting systems. The obtained results have shown that all studied calixarenes interact with polar domains of bilayer. Depending on functional groups and hydrophobic/hydrophilic properties of calixarenes they can dip into bilayer, locate close to the surface of bilayer or form bridges between positively charged groups of adjacent lipid molecules, thus assisting to disordering or putting in order the lipid molecules. © 2011 Springer-Verlag

Modification of secondary disease mortality. Abstr.

The influence of p-tert-butyl thiacalix[4]arenes (1,3-alternate) functionalized by N-propyl morpholine, N,N-dipropyliden-amine and aminodiacetate fragments on dynamic structure of liposomal membranes prepared from dipalmitoyl phosphatidylcholine was investigated by means of electron spin resonance spin-probe technique and Fourier transform infrared spectroscopy. Nuclear magnetic resonance and transmission electron microscopy techniques were applied to characterize the interacting systems. The obtained results have shown that all studied calixarenes interact with polar domains of bilayer. Depending on functional groups and hydrophobic/hydrophilic properties of calixarenes they can dip into bilayer, locate close to the surface of bilayer or form bridges between positively charged groups of adjacent lipid molecules, thus assisting to disordering or putting in order the lipid molecules. © 2011 Springer-Verlag

Catalytic Aquathermolysis of Heavy Oil with Iron Tris(acetylacetonate): Changes of Heavy Oil Composition and <i>in Situ</i> Formation of Magnetic Nanoparticles

We investigated the influence of catalytic aquathermolysis on the composition changes of Ashal’cha heavy oil. The synergetic effect of organic solvent and an oil-soluble catalyst leads to deep conversion of resins into light components. Composition changes of resins and asphaltenes before and after aquathermolysis were investigated by proton nuclear magnetic resonance (¹H NMR), Fourier transform infrared spectroscopy (FTIR), matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS), and elemental analysis. It was shown that iron­(III) tris­(acetylacetonate) forms magnetic nanoparticles (MNPs) during aquathermolysis of heavy oil without any addition of surfactants. Composition of MNPs was determined as a mixture of hematite, magnetite, and maghemite. It turns out that obtained MNPs possess superparamagnetic properties of single-domain nanoparticles

Contribution of thermal analysis and kinetics of Siberian and Tatarstan regions crude oils for in situ combustion process

This research focused on the characterization and kinetics of Siberian and Tatarstan crude oils by gas chromatography, combustion calorimetry, and thermogravimetry (TG-DTG) techniques. Calorimetric experiments show that crude oil with higher saturate content and low resin fraction has higher heating value. TG-DTG curves indicates that the crude oils undergoes two major transitions when subjected to an oxidizing and constant rate environment known as low- and high-temperature oxidations at each heating rate studied. Kinetic analysis in the low- and high-temperature oxidation regions was performed using model-free methods knows as Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose. Throughout the study, it was observed that the activation energy values of the crude oil samples are varied between 41-72 and 145-198 kJ mol(-1) in low- and high-temperature oxidation regions, respectively

Thermochemical Properties of Phase Transitions and Solvation for Some Mono- and Di-cyanate Esters at 298.15 K

We have obtained the thermochemical properties of the phase transition of six mono- and di-cyanate esters for the first time. Vapor pressure–temperature dependences and enthalpies of vaporization for two mono-cyanate esters were measured by fast scanning calorimetry and transpiration method. Fusion enthalpies of cyanate esters were studied by differential scanning calorimetry. We have developed an additive scheme for the evaluation of solvation enthalpies of cyanate esters based on the reliable data of solution and sublimation enthalpies of one mono-cyanate ester. The proposed scheme and experimental solution enthalpies in different solvents were further used for the determination of the vaporization and sublimation enthalpies of other cyanate esters at 298.15 K