The aldol condensation of acetone was carried out under the conditions of the supercritical state of the reagent (350 °C, 8 MPa; 400 °C, 12 MPa) on catalysts prepared by the thermal treatment of ...CaSn(OH)
6
at 450 and 750 °C. The X-ray amorphous phase of CaSnO
3
transforms into crystalline calcium stannate as the thermal treatment temperature increases from 450 to 750 °C. At 350 °C and 8.0 MPa, the selectivity of the reaction to mesityl and isomesityl oxides is about 85% (for both samples), but the conversion of acetone is much higher on CaSnO
3
after it has been thermally treated at 750 °C. The reuse of the CaSnO
3
-450 catalyst led to its transformation. The conversion of acetone increases, and the reaction parameters (conversion and selectivity) reach values characteristic of CaSnO
3
-750. The catalyst structures were studied by XRD and scanning and high-resolution transmission electron microscopies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The innovative strategy of using nanoparticles in radiotherapy has become an exciting topic due to the possibility of simultaneously improving local efficiency of radiation in tumors and real-time ...monitoring of the delivered doses. Yttrium oxide (Y2O3) nanoparticles (NPs) are used in material science to prepare phosphors for various applications including X-ray induced photodynamic therapy and in situ nano-dosimetry, but few available reports only addressed the effect induced in cells by combined exposure to different doses of superficial X-ray radiation and nanoparticles. Herein, we analyzed changes induced in melanoma cells by exposure to different doses of X-ray radiation and various concentrations of Y2O3 NPs. By evaluation of cell mitochondrial activity and production of intracellular reactive oxygen species (ROS), we estimated that 2, 4, and 6 Gy X-ray radiation doses are visibly altering the cells by inducing ROS production with increasing the dose while at 6 Gy the mitochondrial activity is also affected. Separately, high-concentrated solutions of 25, 50, and 100 µg/mL Y2O3 NPs were also found to affect the cells by inducing ROS production with the increase of concentration. Additionally, the colony-forming units assay evidenced a rather synergic effect of NPs and radiation. By adding the NPs to cells before irradiation, a decrease of the number of proliferating cell colonies was observed with increase of X-ray dose. DNA damage was evidenced by quantifying the γ-H2AX foci for cells treated with Y2O3 NPs and exposed to superficial X-ray radiation. Proteomic profile confirmed that a combined effect of 50 µg/mL Y2O3 NPs and 6 Gy X-ray dose induced mitochondria alterations and DNA changes in melanoma cells.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The aldol condensation of acetone under supercritical conditions at 300–400°C and 11.0 MPa was carried out on BaSnO
3
-450 and BaSnO
3
-750 catalysts prepared by calcination of BaSn(OH)
6
at 450 and ...750°C, respectively. Conducting the reaction under these conditions makes it possible to overcome the problem of catalyst deactivation by coking and to obtain valuable chemicals with high selectivity. At 300°C, both catalysts provide selectivity of 85–87% to isomeric mesityl oxides (C
6
products). At 400°C with the BaSnO
3
-450 catalyst, the selectivity significantly changes from C
6
to C
9
(phorones). Powder X-ray diffraction and TEM data attest to the multiphase nature of the samples, which contain barium stannates, barium carbonate, and tin oxide. It was found that the catalyst structure rearranges
in situ
, which greatly affects the catalytic properties and is most pronounced for BaSnO
3
-450.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The transformation of hydrolysis lignin in water under sub- and supercritical conditions (320–800 °C, 10.0 MPa) in the presence of iron(
iii
) ions was studied. At temperatures above 400 °C, two ...processes are most significant: deep depolymerization of lignin to phenolic monomers and condensation of aromatic moieties of lignin into carbonaceous deposits. In the presence of Fe
3+
ions, the content of monomeric phenols increases 3–4-fold, which is indicative of the catalytic effect of iron in lignin depolymerization. When the reaction temperature increases from 400 to 660 °C, the content of monomeric products (mainly, phenol and guaiacol) increases from 1.8 to 7.5 wt.%. Under the same conditions, considerable gasification of lignin monomers and oligomers to a hydrogen-rich mixture (up to 38 vol.%) takes place. The yield of carbon-containing gaseous products is independent of the presence of Fe
3+
ions, retaining a value of 27% in terms of carbon. Further temperature rise up to 800 °C decreases the content of the monomeric products of depolymerization and increases the contribution of gaseous products. In this case, the condensation of phenolic moieties to give carbonaceous deposits becomes the predominant reaction. The interaction of the Fe
3+
ion with the β-O-4-dimer of coniferyl alcohol was studied by quantum chemical calculations. According to the calculation results, in the presence of iron, the electron density of the highest occupied molecular orbital of the dimer partially shifts towards the iron ion, which facilitates cleavage of the C—bond.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Distributed generation in the electrical network causes a redistribution of power and leads to a reduction in technological losses and a decrease in voltage deviations for consumers. The installation ...of additional generators of electric energy based on the use of wind generators and photovoltaic systems has become widespread in the world energy industry, and has now received development in the Russian Federation. It is shown that the connection of an additional source based on photovoltaic systems can reduce losses in a supply line. According to results of the analysis of a possible location of the connection of an additional power supply on a line with a uniformly decreasing or increasing load, it is proved that the greatest reduction in the level of losses in a line is achieved when additional power supply is connected to it in the case of increase in the load from the beginning to the end. Analytical expressions for determination of economically expedient capacities and a place of connection of an additional source for linearly decreasing or increasing specific load of a supply line are presented. There was determined the optimal power of an additional power source in the form of a photovoltaic system and the optimal point of its connection on a line to reduce power losses during power transmission.
Oil-water-saturated formations of Western Siberian fields represented by polymictic sandstones are often characterized by strong granulometric heterogeneity. This is the reason for an incorrect ...assessment of the physicochemical properties of reservoirs, including wettability. On the example of the BS9 - BS11 formations of two fields of Surgut oil and gas region, the distribution of wettability of core samples was analyzed. An analysis of the modeling results for the hydrocarbon phase displacement by oil-saturated reservoir water was carried out using the Tulbovich method. To assess reliability of the wettability values, it was proposed to correlate the difference in the masses of water and kerosene displaced during capillary impregnation and centrifugation with differences in the mass of water and kerosene in water-and kerosene-saturated samples. The method was used to plot the distribution of porosity, permeability and relative clay content on the wettability parameter by capillary impregnation and centrifugal displacement. The results obtained were compared with similar dependences of the reservoir properties and clay content on the general wettability parameter. The type of wettability of core samples with good reservoir properties is validated in complex, low-permeability reservoirs with a high content of clay material. It is recommended to use the results of modeling the displacement by capillary impregnation and centrifugation with differences in the mass of water and kerosene.
The article presents an overview of the IV Forum “Sociology of Health: Contemporary Healthcare in Dialogue with Everyone” organized by the Research Institute for Healthcare Organization and Medical ...Management of the Moscow Healthcare Department on November 17, 2022. The article summarizes presentations made by sociologists, heads of medical organizations of Moscow and other Russian regions, academic researchers, and representatives of non-profit organizations. The authors identify four key social and humanistic aspects of dialogue in the healthcare system: value basis, methodology, role of the civil society, and main issues. The Forum focused not only on methodological issues, but also on the applied research, such as projects aimed at smoking cessation, motivating to blood donation, developing psychological support service for cancer patients, etc. The authors emphasize the need for social-humanitarian technologies in the healthcare system for its patient-oriented transformation, including introduction of sociological monitoring.
Aldol condensation of acetone on strontium stannate is studied at a temperature of 250–400°C and a pressure of 2.5 and 12.5 MPa. The main reaction products are mesityl oxide and isophorone. It is ...shown that the SrSnO
3
catalyst is stable under supercritical conditions and its productivity with respect to mesityl oxide isomers at 350°C and 12.5 MPa equals 9 g h
–1
, which is higher than in the gas phase.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We present results of studying the sensitivity of an acoustic method for gaging the density of thermally expanded graphite (TEG) samples based on recording changes in the amplitude of a signal ...transmitted through the sample due to a change in density. They show that the maximum sensitivity of the method is comparable with the error of measurement of density and mass by the direct weight method, 26 kg/m
3
and 0.02 g, respectively. The unevenness of the density distribution over the area of TEG samples of various thicknesses was estimated, while the deviation of the amplitude of the signal transmitted through the sample, proportional to the density deviation, reached up to 50% for some sheets, 30% for mats, and the smallest did not exceed 10%. During the scanning process, an inversely proportional dependence of the amplitude of the transmitted acoustic signal on the average sample density was revealed. This dependence was most pronounced for small thicknesses of TEG mats and sheets.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
10.
Wettability and formation conditions of reservoirs Malyarenko, A M; Bogdan, V A; Kotenev, Yu A ...
IOP conference series. Earth and environmental science,
11/2019, Volume:
378, Issue:
1
Journal Article
Peer reviewed
Open access
The analysis of the relation between the wettability of mineral substance, the porosity and permeability properties of the rock and the nature of the distribution of hydrocarbons was made based on ...the core samples of the BS-1 and BS-2 productive strata of the Surgut oil and gas field. It was proposed to study the association of hydrophobic, hydrophilic, and mixed groups of collectors to different facies.
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