Phase formation in the Ag2MoO4–Rb2MoO4–Hf(MoO4)2 system

Systematic studies of the subsolidus structure of ternary molybdate systems allow expanding the representation of ternary molybdates. In this paper we studied the solid phase interaction in the Ag2MoO4–Rb2MoO4–Hf(MoO4)2 system for the first time using X-ray phase analysis.To determine the quasi-binary sections, we use the method of “intersecting cuts”. It helped to reveal the formation of new Rb5Ag1/3Hf5/3(MoO4)6 and Rb3AgHf2(MoO4)6 phases. We also determined their thermal characteristics using differential scanning calorimetry. The ternary molybdate Rb5Ag1/3Hf5/3(MoO4)6 crystallised in the trigonal syngony with the followingunit cell parameters: a = 10.7117(1), c = 38.5464(5) Å (space group R3с, Z = 6). The Ag2MoO4–Rb2MoO4–Hf(MoO4)2 system is characterised by the existence of ten quasi-binary cross sections.The experimental data obtained in this work complement the information on phase equilibria in condensed ternary systems containing molybdates of tetravalent elements and two different monovalent elements. This provides opportunities for the combination of the compositions of ternary molybdates due to cationic substitutions, which will allow controlling their properties.

Study of succinic anhydride amidation by 2-aminothiazol

The reaction between succinic anhydride and 2-aminothiazole was carried out in polar organic solvents (acetone, 1,4-dioxane, isopropanol) and in a mechanochemical reactor. By of X-ray phase analysis, IR, 1H, 13C NMR spectroscopy it was found that in both techniques of carrying out the reaction, the only product was succinamide. It was shown that the process efficiency in the mechanochemical reaction conditions is higher in comparison with the traditional solution’s synthesis. The solid-phase interaction development was proceeded during 45 days after load removed, it was especially intense in the first 10 days.

Formation of the Diffusion Zone in Explosion Welded Composite Cr20Ni80 - AD1 at Liquid-Phase Interaction

The paper presents the investigation on the structure, chemical and phase composition of the diffusion coating formed during the liquid-phase heat treatment in the explosion-welded Cr20Ni80 + AD1 bimetal. It is shown that the coating structure consists of NiAl3, CrAl7, Ni2Al3 intermetallic inclusions, as well as a metastable ternary compound – τ2-phase (Al77.5Cr12.5Ni10) of different dispersion and morphology. There are no crystallization defects in the coating structure.

FORMATION OF THE STRUCTURE AND COMPOSITION OF THE DIFFUSION INTERACTION ZONE DURING THE HEAT TREATMENT OF THE EXPLOSION-WELDED AD1 + Cr20Ni80 COMPOSITE IN THE PRESENCE OF A LIQUID PHASE

The paper presents the study results of the structure, chemical and phase composition of the diffusion coating formed during the heat treatment of the explosion-welded Cr20Ni80 + AD1 bimetal according to the regime providing liquid-phase interaction (above the melting point of aluminum) on the surface of the Cr20Ni80 alloy. It is shown that its structure consists of inclusions of NiAl, CrAl, NiAl intermetallic compounds, as well as a metastable ternary compound - τ-phase with composition of AlCrNi of different dispersion and morphology. There are no crystallization defects in the coating structure.

Multiphase technologies in oil-gas production

Emergency cases, complications, maximum energetic cost, human and material expenses, negative impact on the environment in the oil-gas production taking place in the system “ well – oil and gas collection” are predominantly associated with the multiphase and multicomponent well production. Considering the research results of recent years, we can mark that in the view of hydraulic properties of the flows and interactions of seperate phases, currently are formed multiphase technologies, on the basis of which solution of various issues and increase of efficiency of technological processes in production, collection, transportation and storage of oil and gas becomes possible. The paper reviews the perspectives of solution of few issues of oil-gas production using multiphase technologies, on the basis of which the phase interaction lies. Some problems of oil-gas production, the solution of which becomes possible with multiphase technologies are noted as well.