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Finding out how cells prepare for fate change during differentiation commitment was our task. To address whether the constitutive pericentromere-associated domains (PADs) may be involved, we used a model system with known transcriptome data, MCF-7 breast cancer cells treated with the ErbB3 ligand heregulin (HRG), which induces differentiation and is used in the therapy of cancer. PAD-repressive heterochromatin (H3K9me3), centromere-associated-protein-specific, and active euchromatin (H3K4me3) antibodies, real-time PCR, acridine orange DNA structural test (AOT), and microscopic image analysis were applied. We found a two-step DNA unfolding after 15–20 and 60 min of HRG treatment, respectively. This behavior was consistent with biphasic activation of the early response genes (c-fos - fosL1/myc) and the timing of two transcriptome avalanches reported in the literature. In control, the average number of PADs negatively correlated with their size by scale-free distribution, and centromere clustering in turn correlated with PAD size, both indicating that PADs may create and modulate a suprachromosomal network by fusing and splitting a constant proportion of the constitutive heterochromatin. By 15 min of HRG treatment, the bursting unraveling of PADs from the nucleolus boundary occurred, coinciding with the first step of H3K4me3 chromatin unfolding, confirmed by AOT. The second step after 60 min of HRG treatment was associated with transcription of long noncoding RNA from PADs and peaking of fosL1/c-mycresponse. We hypothesize that the bursting of PAD clusters under a critical silencing threshold pushes the first transcription avalanche, whereas the destruction of the PAD network enables genome rewiring needed for differentiation repatterning, mediated by early response bivalent genes.

The results of studying the effect of silicon concentration of ferrosilicon: FeSi5 (5% Si), FeSi20 (20% Si), FeSi35 (35% Si), FeSi50 (50% Si), FeSi65 (65% Si) on the degree of nickel (ηNi) and iron (ηFe) reduction of the CaO-SiO2-MgO-Al2O3-FeO-NiO-P2O5 multicomponent oxide system at a temperature of 1500 °C by thermodynamic simulation are given2. The HSC Chemistry 6.12 software package developed by Outokumpu (Finland) was used for the simulation. The chemical compounds Ni3Si and Ni5Si2 with the corresponding thermodynamic characteristics are entered into the database. The calculations were performed by the “Equilibrium Compositions” subroutine at a gas pressure of 1 atm, containing 2.24 m3 N2, as a neutral additive. The obtained modeling results indicate the thermodynamic possibility of nickel and iron reduction from the CaO-SiO2-MgO-Al2O3-FeO-NiO-P2O5 oxide system by silicon of ferrosilicon. The degree of iron reduction increases from 88.8 to 91.4%, with an increase in the silicon concentration of ferrosilicon [Si]FeSi from 5 to 65%. The degree of nickel reduction with an increase in the silicon concentration of ferrosilicon remains almost unchanged and amounts to 99.8-99.7%. The degree of use of silicon is 92.1–94.5%. The chemical composition of the complex alloy – ferrosiliconickel is determined. The obtained simulation results can be used to develop the technology for producing ferrosiliconickel from nickel ore by silicothermic method.

Analysis of forming chromium-bearing ferroalloys production waste in Russian Federation was performed. Chemical, phase, fractional compositions and physico-chemical, technological properties of high-carbon ferrochromium slag were defined. Physico-chemical, thermo-mechanical and thermo-physical properties of fire-resistant materials, obtained from ferrochromium production slag and dust, were researched. It was shown that researched waste may be utilized as raw for fire-resistant materials production. Because of their chemical and phase composition, researched materials may be utilized for production of forsterite-spinel-based and forsterite-spinel-periclase-based fire-resistant materials. Technological properties of researched materials allow obtaining dense strength fire-resistant materials. Such fire-resistant materials are promising in the field of ferrous metallurgy (lining up furnaces, ladles and overflow launders in ferroalloys production).

In this paper the analysis of the processes for spontaneous decay of slags from the production of refined ferroalloy grades is performed. It is shown that the main reason for the decay is the formation of a dicalcium silicate in highly basic melts with CaO / SiO2 ratio of 1.5-3.1. Based on the performed studies, three main promising directions for the stabilization of slags of ferroalloy production have been formed. First direction is the replacement of the calcium cation (or transformation) in a dicalcium silicate, for example, with the magnesium cation or the production of non-decaying compounds of the gehlenite type (2CaO·Al2O3·SiO2), mainly due to the application of phase composition peculiarities of the waste rock for ferroalloy raw materials. Second direction is the reduction of the dicalcium silicate content with a decrease in the ratio of CaO / SiO2 in the slag less than 1.4, due to the separation of the silicothermic reduction process into two stages, obtaining in the first stage a low-basic (CaO / SiO2 = 1.3-1.4) non-decaying tailing slag, and on the second one - highly basic return slag (1.8-1.9), which is used in the first stage of this technological chain. The third direction is the replacement of the SiO anion of dicalcium silicate with other anions, for example, ВО by means of small additions of calcium borate, colemanite, etc. A possibility for stabilization of ferroalloy production slags with obtaining of construction crushed stone corresponding to the requirements of TU 0798-69-00186499-2014 "Crushed stone and sand from ferroalloy slags. Technical conditions», is shown experimentally.

In this article the time and heat dependence of the nitrogen distribution upon steel alloying of 04Cr20Ni6Mn11Mo2NVNb steel grade by the nitrided manganese of Mn85N10 grade at the holding in the air atmosphere from 2 to 30 minutes in the temperature range 1450-1550 °С was experimentally determined. It was determined that the highest degree of nitrogen transition into steel is 99% and is observed with a short holding time of 2 min (after the introduction of nitrided manganese into the steel melt) in the low-temperature region ~ 1450 °С. Further holding and / or temperature growth results in the release of nitrogen in the gaseous form, due to the thermal dissociation of the nitrogen-containing compounds contained in the melt and removal of nitrogen from the melt into the gas phase, which leads to a decrease in the degree of nitrogen transition to the steel. The key possibility for obtaining a steel of the indicated grades group with a nitrogen content of 0.45-0.6% is shown when alloying in an air atmosphere in a low-temperature region (1450-1500°C), while optimizing the holding time.