[en] Highlights: • Consistent enthalpies of formation and lattice energies of crystalline Pr₄N⁺ halides were selected. • The standard molar enthalpy of formation of gaseous Pr₄N⁺ ions was obtained. • The standard molar enthalpy of hydration of Pr₄N⁺ was estimated. - Abstract: The standard molar enthalpies of formation of crystalline tetraalkylammonium halides, Δ_fH°(R₄NX, c), R = Me, Et, Pr, Bu and X = Cl, Br, I, and the corresponding lattice energies, U_L(R₄NX) were obtained from the literature as far as available for T = 298.15 K. From consistent values of these two quantities and values for Δ_fH°(X⁻, g) the standard molar enthalpies of formation of the gaseous cations were obtained from Δ_fH°(R₄N⁺, g) = Δ_fH°(R₄NX, c) + U_L(R₄NX) + 2RT° − Δ_fH°(X⁻, g). The value for the hitherto unreported Δ_fH°(Pr₄N⁺, g) = (307 ± 7) kJ · mol is here derived. The value for the absolute standard molar enthalpy of hydration is Δ_hH°(R₄N⁺, aq) −210 kJ · mol⁻¹, but may have an appreciable uncertainty, reflecting that of Δ_fH°(R₄N⁺, aq), obtained from interpolation of values for the Me, Et, and Bu analogues

[en] Full text: A number of new compound esters of acetylenic raw by etherification of oil naphtenic acids with acetylene alcohols and glycols in the presence of the catalyst of cat ion exchange resin KY-2 have been synthesized. It is shown that obtained acetylene esters easily enter into the reaction of hydrosillicylatig, aminoomethylating, of oxidizing, dimerization and hydration generating the new derivatives of oil naphtenic acids and may be applied as anticorrosive additives to motor oils

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No abstract available

[en] From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium M⁺(aq) + Cs⁺(org) ↔ M⁺(org) + Cs⁺(aq) taking place in the two-phase water-phenyltrifluoromethyl sulfone (abbrev. FS 13) system (M⁺ Li⁺, H₃O⁺, Na⁺, NH₄⁺, Ag⁺, Tl⁺, K⁺, Rb⁺; aq = aqueous phase, org FS 13 phase) were evaluated. Furthermore, the individual extraction constants of the M⁺ cations in the mentioned two-phase system were calculated; they were found to increase in the series of Li⁺ < H₃O⁺ < Na⁺< NH₄⁺ < Ag⁺ < Tl⁺ < K⁺ < Rb⁺ < Cs⁺. (author)

[en] Energy of preference of Ti²⁺, Ti³⁺, V²⁺, V³⁺, V⁴⁺, Cr³⁺, Cr⁴⁺, Cr⁶⁺ ions to octahedral positions is calculated using the equation connecting heats of oxide atomization and characteristic distances of metal-oxygen

[en] Photochemical reactions of Np(V) and Np(VI) in 0.001-1.0 M HClO₄ solutions were studied. Both oxidation of Np(V) and reduction of Np(VI) occur under UV irradiation of such solutions, the efficiency of the first reaction increasing, and that of the second reaction decreasing with increasing acid concentration. Possible mechanisms of reactions were discussed. The probabilities of various reactions were calculated. It was shown that the mechanisms proposed in the literature do not agree with the experiment. The photochemical reactions of neptunium are proved to involve formation of excimers - dimers consisted of excited and unexcited neptunium ions

[en] In view of contradictory data on the existence of Ac²⁺ in aqueous solutions, the possibility of actinium reduction was examined in aqueous-ethanolic solutions in which bivalent f-elements are more stable than in aqueous media. In the presence of bivalent samarium (E_Sm⁰3+/Sm 2+=-1.5 V) Ac(III) is not reduced to Ac(II). These results disagree with the previously published data on the radiopolarographic generation of Ac(II) in aqueous solutions

[en] A satisfactory method was established for synthesizing four samples of tin (IV) antimonates. The stability of the prepared materials increases with decreasing the Sb/Sn molar ratios, its ion exchange capacity was found in the order of Sn Sb-IV > SnSb-III > SnSb-II > SnSb-I, where the material having the greater antimony content had greater uptake of ions due to the increased acidities of the species by increasing the antimony. Straight lines are obtained for the plots of distribution coefficients (k_d) against HNO₃ concentrations for ¹³⁴Cs, ⁸⁵Sr, ⁶⁰Co and 152+154Eu.

[en] Full text: The investigation of changing the content of colloidal fraction in the water dispersions of Dashasalakhly montorillonite (DM) under the influence of the number of non-organic exchanging cat ions as well as the little additives of cat ion-active surface -active substance-rod amine has been carried out