Biological activity of some sulfur- and selenium-containing spiro compounds

Russian Chemical Bulletin - Cytotoxicity to K-562 leukemia cell line of two spiro compounds containing selenium or sulfur atom in their structure were compared....     

Silicon production from phosphate industry waste (Na2SiF6)

Production of salable goods from industrial waste can become an additional innovative component of liquid-metal technology of atomic engineering. In this paper, we used sodium silicofluoride (Na₂SiF₆), i.e., phosphate Ca(HPO₄)₂ production waste. Fundamentals of a worldwide unique ecologically clean low-temperature technology of Si reduction from Na₂SiF₆ and Si deposition on substrates in a liquid-metal loop in a single process was developed, as well as a gas-phase technology of Si reduction by sodium from gaseous SiF₄ released during thermal dissociation of Na₂SiF₆.     

Effects of some 5-anilino-1,2,4-thiadiazole derivatives onto leukemic cells

Russian Chemical Bulletin - The antileukemic activities of some thiadiazole derivatives in the forms of hydrochlorides and salicylates have been determined. The insertion of salicylate ion in the...     

Heat capacity of the white pine biocarbon preform and the related biocarbon/copper composite

This paper reports on measurements in the 80–300-K temperature interval of the heat capacity at constant pressure C _p (T) of high-porosity amorphous white pine carbon preforms (biocarbon) prepared by pyrolysis (carbonization) at T _carb = 1000 and 2400°C in an argon flow. The dependences C _p (T) for biocarbon/copper composites based on the carbon preforms obtained have also been determined. It is shown that the mixture rule holds for the composites, i.e., that C _p (T) of the composite is a sum of the heat capacities of the constituent materials taken in the corresponding ratios. Phonon mean free paths for the white pine carbon preforms prepared at T _carb = 1000 and 2400°C have been calculated and used to estimate the size of the nanocrystallites contributing to formation of the carbon frameworks of these preforms.     

Relationship between the aggregation of nanoparticles bearing zinc ions and cytotoxicity and morphology of blood cells

The effect of nanoparticles bearing magnetic and nonmagnetic zinc nuclei on lymphocytes from healthy donors and leukemic cells of patients (15–20 years old) with acute B-lymphoblastic leukemia (B-ALL) and acute myeloid leukemia (AML) was considered. The studies by confocal and fluorescence microscopy showed an apoptotic effect of nanoparticles bearing zinc ions. An increase in the aggregation of the nanoparticles and cell self-aggregation, resulting in a decrease in cytotoxicity, were observed in the case of the magnetic isotope. In spite of this, cell apoptosis under the action of even aggregated nanoparticles bearing magnetic ⁶⁷Zn was significantly higher than the apoptosis with lymphocytes of healthy donors and with nanoparticles bearing zinc of the total isotope composition.     

Effect of synthesis conditions on the mechanism of reversible inhibition in the TEMPO-mediated polymerization of 4-vinylpyridine

The effects of polymerization conditions (the types and concentrations of initiator and solvent, the TEMPO-to-initiator molar ratio, and temperature) on the kinetics and mechanism of pseudoliving radical polymerization of 4-vinylpyridine mediated by the nitroxide TEMPO are studied. The key quantitative parameters of the process are calculated: namely, the rate constant of reinitiation, the rate constant of inhibition, and the product of the propagation-rate constant and the pseudoliving equilibrium constant. The optimum conditions for the controlled synthesis of poly(4-vinylpyridine) mediated by TEMPO are ascertained.     

Separation of 4C-Substituted Pyrrolidin-2-One Derivatives on Amylose-Based Chiral Stationary Phases

Chromatographia - Our previous studies concerning the enantioseparation of 4C-substituted pyrrolidin-2-one derivatives on coated polysaccharide-based chiral stationary phases have shown that...     

On One method for the numerical solution of a system of parabolic equations

An algorithm for the numerical solution of a system of two parabolic equations of a special form has been presented, and its stability has been proved. Estimates of the numerical solutions obtained have been made. Conditions guaranteeing the applicability of the sweep method are determined, and the time step at which the iterative method has the inner convergence has been estimated. An example of the application of the algorithm in soil science has been presented.