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The effect of quasi-hydrostatic pressures up to 100 kbar is investigated on the phase transitions of Fel -a h , alloys by resistivity measurements. The pressure dependence of the first order antiferromagnetic (AF) to ferromagnetic (FM) phase transformation temperature dTk/dp = 4.4 to 6 K/kbar. The pressure dependence of the second order FM to paramagnetic (PM) transition, i.e. that of the Curie-point is dTc/dp = -0.7 K/kbar. At about 60 kbar the thermal hysteresis diminishes, and above the range of the co-existence of three phases (AF-FM-PM) the pressure dependence of the AF-PM transition is characterized by dT/dp = 0.6 to 1.0 K/kbar. The AF-PM transition is investigated in an Ir-substituted alloy (Fe&h4~.&6.5) also, where dT/dp = 0.6 K/kbar.

In recent years, forest fires have covered many parts of the Republic of Sakha (Yakutia). The fires often threaten populated areas and Indigenous communities as well. In 2020–2021, the fires caused enormous economic and environmental damage and the exact amount is yet to be fully calculated. Concerns about the sheer scale of carbon emissions into the atmosphere were widely discussed by world media. Social scientists of the Republic of Sakha (Yakutia) raised the following questions: how do Indigenous communities live in a condition of constant threat from annual forest fires? What environmental, social, and economic challenges do they face, what do they fear, and what are their expectations? We reviewed Indigenous traditional knowledge related to fire management and firefighting techniques and analyzed Indigenous peoples’ perceptions of changes in the ecological balance of water resources and permafrost. The authors also discuss the causes of forest fires, connections with industrial and transport development, and social consequences. The article is based on 2010–2021 field studies.

The influence of a high magnetic field on the band structure and optical conductivity of FeSi has been studied by the ab initio full-potential LMTO-PW and relativistic LMTO-ASA methods with an applied field included. It is found that the applied external magnetic field induces a metallic magnetic state through a first-order metamagnetic transition, i.e. at a critical magnetic field of about H cr = 170 T there is a large steplike increase in the calculated magnetization, with a magnetic moment of 0.7 µ B . The magnetized state persists while the field is gradually reduced from above the metamagnetic transition (a hysteresis effect). The calculated optical conductivity (OC) at the critical field H cr differs substantially from the zero-field OC in the infrared region.

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