Thermo-Oxidative Degradation of Hydroxypolychlorobiphenyls

Russian Journal of General Chemistry - The degradation of hydroxy derivatives synthesized from individual di-, tri-, tetra-, and pentachlorinated biphenyls as typical representatives of commercial...     

Improving stability and thermal properties of TiO2-based nanofluids for concentrating solar energy using two methods of preparation

Journal of Thermal Analysis and Calorimetry - Nanofluids are considered a promising alternative to the classic fluids used in heat transfer processes. One interesting application of nanofluids is...     

Calorimetric (DSC) and dielectric (TSDC) investigation on the thermal behavior and molecular mobility in the supercooled liquid and glassy states of bifonazole and lamotrigine

Journal of Thermal Analysis and Calorimetry - The thermal behavior of the two glass-forming drugs bifonazole and lamotrigine was studied by differential scanning calorimetry (DSC); we reported a...     

Zinc-containing derivatives of 2-aminopyrimidine

A platform containing three anticancer components is proposed. The components are a radioactive ⁶⁹mZn isotope and zinc complexes, where both zinc and ligand exhibit anticancer properties. Two zinc-containing complexes, namely (2-AP)₂ZnCl₂ and (2-AP)₂Zn(Sal)₂ (AP is 2-aminopyrimidine, Sal is salicylate) were synthesized and characterized. Their cytotoxicity with respect to some leukemia cell lines is demonstrated. Their stability in physiological solution and percentage of apoptosis (by flow cytometry) are investigated. Stable complexes of compounds with the isotope ⁶⁹mZn were characterized by TLC and autoradiography.     

Functional copolymers with triazole and acetate fragments

New functional copolymers of different composition with triazole and acetate fragments in the macromolecules were synthesized by free radical copolymerization of 1-vinyl-1,2,4-triazole with vinyl acetate. The reactivity of the comonomers was studied and the monomer copolymerization constants were calculated. The structure and composition of the copolymers were determined by elemental analysis, IR and ¹H NMR spectroscopy.     

Carane amino alcohols as organocatalysts in asymmetric aldol reaction of isatin with acetone

Carane-derived β-amino alcohols with amino and hydroxy groups at positions 3 and 4 differing in their mutual arrangement and configuration were synthesized. Their application as organocatalysts in the asymmetric aldol reaction of isatin with acetone allowed one to obtain adducts with up to 84% enantiomeric excess.     

Checking of applicability of conditions for reaching the limiting-current mode to flow-by porous electrodes

For the flow-by porous electrodes, which differ in thickness, specific surface area, solution flow rate, and a ratio between the phase conductivities, the conditions providing the limiting-current mode over the entire electrode surface at nearly 100% current efficiency are determined using the method of successive refinement of total current and profile of its distribution along the solution flow. The used values of electrode thickness L are compared with available estimates for the limiting thickness of porous electrode L _lim derived for the ideal limiting-current mode and calculated using real values of the width of the limiting-current plateau of overall polarization curve, solution conductivity, and the diffusion limiting current in the zone of solution input into the electrode. It is found that these values are close to each other in all cases. The largest error of estimation of L _lim does not exceed 10% indicating that it can be used for preliminary estimation of the conditions for reaching the limiting-current mode for the flow porous electrodes of this type.     

Expanding Lipidome Coverage Using LC-MS/MS Data-Dependent Acquisition with Automated Exclusion List Generation

Untargeted omics analyses aim to comprehensively characterize biomolecules within a biological system. Changes in the presence or quantity of these biomolecules can indicate important biological perturbations, such as those caused by disease. With current technological advancements, the entire genome can now be sequenced; however, in the burgeoning fields of lipidomics, only a subset of lipids can be identified. The recent emergence of high resolution tandem mass spectrometry (HR-MS/MS), in combination with ultra-high performance liquid chromatography, has resulted in an increased coverage of the lipidome. Nevertheless, identifications from MS/MS are generally limited by the number of precursors that can be selected for fragmentation during chromatographic elution. Therefore, we developed the software IE-Omics to automate iterative exclusion (IE), where selected precursors using data-dependent topN analyses are excluded in sequential injections. In each sequential injection, unique precursors are fragmented until HR-MS/MS spectra of all ions above a user-defined intensity threshold are acquired. IE-Omics was applied to lipidomic analyses in Red Cross plasma and substantia nigra tissue. Coverage of the lipidome was drastically improved using IE. When applying IE-Omics to Red Cross plasma and substantia nigra lipid extracts in positive ion mode, 69% and 40% more molecular identifications were obtained, respectively. In addition, applying IE-Omics to a lipidomics workflow increased the coverage of trace species, including odd-chained and short-chained diacylglycerides and oxidized lipid species. By increasing the coverage of the lipidome, applying IE to a lipidomics workflow increases the probability of finding biomarkers and provides additional information for determining etiology of disease.

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Contribution of the surface dipole moment and the contact potential-induced disjoining pressure to the stress balance at a three-phase contact

The contact between three insulators results in a set up of contact potentials related to the adsorbed dipole moment at each surface. The produced electric field applies force (disjoining pressure) on each interface. This disjoining pressure is a long-ranged force (1/distance²) which is proportional to the difference between the dielectric permittivities of the phases on the two sides of the interface and, for small angles, to the square of the contact angle. The contact potential leads to a logarithmic perturbation of the profile of the three-phase contact zone.     

Adsorption of nonionic surfactant on porous and nonporous poly(ethylene terephthalate) films

The application of surfactants in the chemical etching of track membranes enables one to control their pore shape. To find out the mechanism of the surfactant action on the track etching in the nanometer range of pore sizes, the adsorption of a nonionic surfactant (polyoxyethyelene-4-nonylphenyl ether) on porous and nonporous poly(ethylene terephthalate) films has been studied. The experimental results have been analyzed in comparison with the data previously obtained on the adsorption of an anionic surfactant on similar films. It has been concluded that the behaviors of anionic and nonionic surfactants in negatively charged pores about 100 nm in radius are strongly different due to the electrostatic exclusion of co-ions from the pores, which is of significance only for compounds dissociating into ions.