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The goal of the study is to make a comparative analysis of the dynamics of indices of economic indicators and sufficiency indicators used to calculate an urban environment quality index of a Russian municipality. The city of Kirov, Russia, was taken as a sample for the study, which went on from 2012 through 2018. The analysis demonstrated practically no statistically significant correlations in the dynamics of indices of individual subgroups of indicators, as well as in the dynamics of indices of individual indicators, although with a few exceptions. The results of the study confirm the need to improve the methodology of calculating the integral indices of cities and regions. These indices are related to urban ecology, quality of life, and sustainable development issues. The results also demonstrated the inadequacy of such tools for systematic and comprehensive international analysis of today urbanization problems.

A small amount of LaAlO3 added to a La2O3:3TiO2 starting oxide mixture stabilizes the A-deficient La2/3TiO3 perovskite structure. According to XRD and microstructural investigations of samples prepared in the ternary system at 1400ºC, only the solid solution along the La2/3TiO3-LaAlO3 tie-line extends from at least 4 mol% LaAlO3 to pure LaAlO3.

A study of a two-stage method for the formation of nanostructured Ni3Fe is presented. Nanostructured Ni3Fe hollow microspheres were synthesized by ultrasonic spray pyrolysis (URP) from a mixture of aqueous solutions (10 wt.%) of nickel(II) and iron(III) nitrates. In the first stage, hollow microspheres with diameters in the range 0.5 – 10 μm were formed from a mixture of Ni and Fe oxides. The second stage involved metallization of a mixture of Ni and Fe oxides in a tube furnace in a hydrogen atmosphere. X-ray diffraction (XRD) data of the final product showed the presence of the Ni3Al phase and a crystallite size close to 40 nm. Scanning and transmission electron microscopy revealed the hollow morphology of the studied Ni3Fe microspheres. Their walls were assembled from crystallites with diameters of 30 – 60 nm. [ABSTRACT FROM AUTHOR]

The aim of the study is to develop a methodological approach to assessing the incremental effi-ciency of electricity generation at CHPPs (specific heat consumption for changing electric power of turbine) in operating modes, taking into account both energy and environmental indicators. To achieve this goal, the following tasks were solved: the methodology, based on mathematical models of cogeneration steam turbines, both integral and differential indicators of heat rate per unit of electricity generation increment, was justified; a comprehensive generalization of the cal-culation data on the turbine T-50-12.8 type was performed; a quantitative assessment of the in-tegral electricity generation and greenhouse gas emissions parameters was made at various loads and its comparison with the corresponding indicators in condensation mode. The most signifi-cant results are the following: generalized dependences of the integral specific heat consumption per unit of increase in electricity generation and carbon footprint were calculated for a wide range of changes in operating conditions; boundary conditions were established under which obtaining these parameters by opening the sliding grid of low-pressure section turns out to be energetically and ecologically feasible; it was determined that when increasing the capacity without bypassing the delivery water, the carbon footprint increment with an increase in the ca-pacity of cogeneration turbines by opening the sliding grid will be less than for condensing tur-bines. The significance of the results obtained lies in their applicability for solving problems of ensuring maximum efficiency during involving cogeneration turbines in regulating electric load schedules in different boundary conditions.

Physicomechanical properties and structure of mullite-corundum unmolded refractories are investigated and tests of a pilot batch of refractory products for various purposes are conducted. The effect of the adding nanosize SiO2 (1 wt.%) on strength, structural (density, porosity) and operational properties of unmolded refractories is studied. Results show that this additive contributes to formation of a structure with high apparent density and compressive strength (2.93 and 2.98 g/cm3, 87.3 and 162.1 MPa, respectively for two types of refractories), reduces open porosity from 20 to 14%, and also increases the life of refractory products (according to operating duration) by 25 – 35% compared with basic refractory life. The use of SiO2 nanoparticle additives reduces refractory product and raw material consumption for their manufacture, and also increases production profitability. [ABSTRACT FROM AUTHOR]