STRUCTURE, PHYSICAL AND MECHANICAL PROPERTIES OF ALUMINIUM-GADOLYNIUM MASTER ALLOYS OBTAINED BY EXCHANGE PROCESSES

The exchange reaction between aluminum metal and gadolinium fluoride is proposed for Gd-Al master alloy synthesis. The structure on the synthesized alloys with different gadolinium concentration was investigated. It was shown that Al and Al3Gd are the main phases in the alloys. Mechanical and thermophysical properties of the obtained masteralloys were measured

STRUCTURE, PHYSICAL AND MECHANICAL PROPERTIES OF ALUMINIUM-REE MASTER ALLOYS OBTAINED BY EXCHANGE PROCESSES

The exchange reactions between aluminum metal and REE fluorides are proposed for Al-REE master alloy synthesis. The structure on the synthesized alloys with different gadolinium concentration was investigated. It was shown that Al and Al3REE are the main phases in the alloys. Mechanical and thermophysical properties of the obtained master-alloys were measured

CONSTRUCTION OF «TIME – TEMPERATURE – PRECIPITATION» DIAGRAM FOR KHN62M ALLOY WITH LOW CARBON CONTENT

The thermal stability of KhN63M alloy with low carbon content was investigated. It was shown that formation of carbide phases does not take place. Phase structure of excessive carbide phases was characterized. The constructed «time – temperature – precipitation» diagram allows to determine the maximal temperature and time of alloy’s operation in contact with molten salts

CONSTRUCTION OF «TIME – TEMPERATURE – PRECIPITATION» DIAGRAM FOR MODIFIED KHN63MB ALLOY WITH LOW CARBON CONTENT

The thermal stability of KhN63MB alloy with low carbon content was investigated. It was shown that formation of carbide phases does not take place. Phase structure of excessive carbide phases was characterized. The constructed «time – temperature – precipitation» diagram allows to determine the maximal temperature and time of alloy’s operation in contact with molten salts

CORROSION, MECHANICAL AND THERMOPHYSICALPROPERTIES OF THE NEW ALLOY ON THE BASIS OF THE SYSTEM «Ni-Cr-Mo» WITH A LOW CARBON CONTENT

The mechanical and thermophysical properties as well as the tendency to intergranular corrosion of the new nickel alloy with low carbon content were investigated. It was found that Physical and mechanical properties of the prepared alloy under high temperature conditions are influenced by changes of structure and composition. In separate series of experiments corrosion resistance of the material was studied in a wide temperature range (450 – 650 °C) in the molten chloroaluminate melts. The rates and the mechanisms of corrosion of the studied materials were determined. The processes taking place during the interaction between metals and melts were investigated

Age Related Changes in NAD+ Metabolism Oxidative Stress and Sirt1 Activity in Wistar Rats

The cofactor nicotinamide adenine dinucleotide (NAD+) has emerged as a key regulator of metabolism, stress resistance and longevity. Apart from its role as an important redox carrier, NAD+ also serves as the sole substrate for NAD-dependent enzymes, including poly(ADP-ribose) polymerase (PARP), an important DNA nick sensor, and NAD-dependent histone deacetylases, Sirtuins which play an important role in a wide variety of processes, including senescence, apoptosis, differentiation, and aging. We examined the effect of aging on intracellular NAD+ metabolism in the whole heart, lung, liver and kidney of female wistar rats. Our results are the first to show a significant decline in intracellular NAD+ levels and NAD∶NADH ratio in all organs by middle age (i.e.12 months) compared to young (i.e. 3 month old) rats. These changes in [NAD(H)] occurred in parallel with an increase in lipid peroxidation and protein carbonyls (o- and m- tyrosine) formation and decline in total antioxidant capacity in these organs. An age dependent increase in DNA damage (phosphorylated H2AX) was also observed in these same organs. Decreased Sirt1 activity and increased acetylated p53 were observed in organ tissues in parallel with the drop in NAD+ and moderate over-expression of Sirt1 protein. Reduced mitochondrial activity of complex I–IV was also observed in aging animals, impacting both redox status and ATP production. The strong positive correlation observed between DNA damage associated NAD+ depletion and Sirt1 activity suggests that adequate NAD+ concentrations may be an important longevity assurance factor

CORROSION, MECHANICAL AND THERMOPHYSICAL PROPERTIES OF THE NEW ALLOY KHN62M

The mechanical and thermophysical properties as well as the tendency to intergranular corrosion of the new nickel alloy with low carbon content were investigated. It was found that physical and mechanical properties of the prepared alloy under high temperature conditions are influenced by changes of structure and composition. In separate series of experiments corrosion resistance of the material was studied in a wide temperature range (450 – 650 °C) in the molten chloroaluminate melts. The rates and the mechanisms of corrosion of the studied materials were determined. The processes taking place during the interaction between metals and melts were investigated