Methane dry reforming over Ni catalysts supported on Ce–Zr oxides prepared by a route involving supercritical fluids

Ce0.5Zr0.5O2 mixed oxides were prepared in a flow reactor in supercritical isopropanol with acetylacetone as a complexing agent. Variation of the nature of the Zr salt and the temperature of synthesis affected the phase composition, morphology and specific surface area of oxides. X-ray diffraction and Raman spectroscopy studies revealed formation of metastable t” and t’ phases. Oxides are comprised of agglomerates with sizes depending on the synthesis parameters. Loading NiO decreases the specific surface area without affecting X-ray particle sizes of supports. Such sintering was the most pronounced for a support with the highest specific surface area, which resulted in the lowest surface content of Ni as estimated by X-ray photoelectron spectroscopy and in the formation of flattened NiO particles partially embedded into the support. The catalytic activity and stability of these samples in the dry reforming of methane were determined by the surface concentration of Ni and the morphology of its particle controlled by the metal-support interaction, which also depends on the type of catalyst pretreatment. Samples based on ceria-zirconia oxides prepared under these conditions provide a higher specific catalytic activity as compared with the traditional Pechini route, which makes them promising for the practical application

Mechanism of ethanol steam reforming over Pt/(Ni+Ru)-promoted oxides by FTIRS in situ

Mechanism of ethanol steam reforming into syngas over Pt/Pr0.15Sm0.15Ce0.35Zr0.35O2 and 10 wt% LaNi0.9Ru0.1O3/Mg-Al2O3 catalysts was studied by in situ FTIRS and pulse titration experiments. Surface species (ethoxy, adsorbed ethanol, acetaldehyde, acetate, etc.) were identified and their thermal stability, routers of transformation and reactivity were characterized. Acetate species were shown to be spectators for both types of catalysts. Transformation of ethoxy species by dehydrogenation is a fast step, while the rate-determining stage is the C–C bond rupture in thus formed acetaldehyde on metal sites. For Pt/Pr0.15Sm0.15Ce0.35Zr0.35O2 catalyst with a high mobility and reactivity of the surface/lattice oxygen of support, efficient oxidative transformation of acetaldehyde at the metal-support interface provides a high yield of syngas at short contact times in the intermediate temperature range with a minor amount of CH4 by-product. Transformation of ethoxy species on the acid sites of alumina-supported catalyst produces C2H4 and (C2H5)2O via dehydration route dominating at temperatures below 400 °C. In addition, for alumina-supported catalyst acetone is produced via aldol formation in the temperature range 400–500 °C due to combined action of metal and support sites. For this catalyst syngas yield is improved at high temperatures when steam reforming of these byproducts efficiently proceeds accompanied by cracking reactions producing also methane as by-product

Cardiometry in oncology: new digital possibilities for analyzing the cardiovascular system state in cancer patients

The new high-tech era begins not with supply of an innovative product to the market, but rather with an intellectual leap in the field of open issues in fundamental engineering, healthcare and education. In the present essay, an example of the successful translation of mathematical, physics- and engineering-related philosophy into the digital platform of Cardiometry is discussed. The theory of hemodynamics, the laws of axiomatics, logic and adaptation can be expressed in terms of mathematics. The original analytical software used in PC-assisted device Cardiocode allows carrying out a phase analysis of the hemodynamics within an extended range. Pilot studies conducted by us in cancer patients at the stages of multi-course chemotherapy have revealed abnormalities and disorders in hemodynamics, energy exchange and adaptation expectancy of the heart at early stages of cancer treatment that is of prognostic significance. Pronounced processes of destabilization in hemodynamics, a suppressed energy exchange and a degradation of adaptation capabilities by the end of the chemotherapy courses involves the appearance of cardiotoxic effects. Based on records covering the specific frequencies discovered in ECG & Rheogram, the R-R interval scatter plots, the metabolic parameters and the Baevsky stress index, we have demonstrated cardioprotective influence made by xenon as a possible solution of the indicated problem. Thus, the Cardiocode technology supports diagnostics by offering an original cardiometric approach, significantly broadening the notion of cardio-oncology from the perspective of the cardiotoxicity pathogenesis under the cancer development conditions and in treatment thereof