Theoretical modeling of the gas humidification effect on the characteristics of proton ceramic fuel cells

Proton ceramic fuel cells are promising electrochemical converters that produce electrical energy by oxidizing hydrogen. Understanding the impact of gas humidification on the characteristics of such fuel cells is pivotal for the development of high-performance devices. This study develops a theory elucidating the effect of hydrogen and air humidity on the output characteristics of fuel cells based on proton-conducting oxide membrane with mixed (proton and hole) conductivity. The theory is based on a self-consistent description of the strong non-uniform distribution of charge carriers inside the membrane and the variation of the gas phase composition along the fuel and air channels. It is shown that the total current density significantly and nonmonotonously depends on humidity of the inlet hydrogen fuel, while humidification of the inlet air has minor effect on the fuel cell characteristics. The influence of the anode and cathode gas humidity on the distribution of the various fuel cell parameters (current densities, resistivity, etc.) along the membrane is also determined. The obtained results reveal the possibility of enhancing the performance of the proton ceramic fuel cells with low polarization losses by optimizing the composition of the inlet hydrogen fuel. © 2019 Elsevier Lt

Age self-assessment of 55-64 years old women as an express method for determining the parameters of life quality in the Circumpolar region

The purpose of this study consisted in the comparative evaluation of the quality of life parameters (QOL) among the female residents of the Arkhangelsk region aged 55-64 years old with different levels of the age self-assessment. The study group (SG) of 104 women reported that they felt at their calendar age (CA) and older. The comparison group (CG) of 252 women - subjectively felt younger than their CA for 5 years or more. For the women surveyed, aging rate (AR) was calculated by the method of V. P. Voitenko (the 3rd version). It was established that the AR indicators in women of the CG were lower than those for women of the SG (p < 0,001). To assess the quality of life, the SF-36v2 questionnaire was used. It was found that all scales and grouped indicators in women in the comparison group were higher than in the study group. The obtained results indicated that the determination of the subjective assessment of wellbeing through a subjectively experienced age (SEA) in women could be an informative indicator of the general state of their health and quality of life as well as an independent important criterion for the prediction of adverse aging risk, the diseases development, as well as the degree of adaptation to the age-related changes

Age self-assessment of 55-64 years old women as an express method for determining the parameters of life quality in the Circumpolar region

The purpose of this study consisted in the comparative evaluation of the quality of life parameters (QOL) among the female residents of the Arkhangelsk region aged 55-64 years old with different levels of the age self-assessment. The study group (SG) of 104 women reported that they felt at their calendar age (CA) and older. The comparison group (CG) of 252 women - subjectively felt younger than their CA for 5 years or more. For the women surveyed, aging rate (AR) was calculated by the method of V. P. Voitenko (the 3rd version). It was established that the AR indicators in women of the CG were lower than those for women of the SG (p < 0,001). To assess the quality of life, the SF-36v2 questionnaire was used. It was found that all scales and grouped indicators in women in the comparison group were higher than in the study group. The obtained results indicated that the determination of the subjective assessment of wellbeing through a subjectively experienced age (SEA) in women could be an informative indicator of the general state of their health and quality of life as well as an independent important criterion for the prediction of adverse aging risk, the diseases development, as well as the degree of adaptation to the age-related changes

Molecular dynamic modeling of thermophysical properties of copper in the region of the melting point

Abstract: Method of molecular dynamics is used for calculation of thermodynamic properties of copper: temperature dependence of melting heat and temperature and pressure dependence of specific heat, coefficient of linear expansion and density. The obtained dependences are compared with experiment. These dependences can be used as input data for the continuum model of pulsed laser heating of matter.Note: Research direction:Mathematical modelling in actual problems of science and technic