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The influence of thermomechanical conditions of induction of the shape memory effects (SME) by bending strain in the Ti-Ni shape memory alloy on the realization of SME and reversible SME (RSME) is studied. The values of reversible SME (ɛ) and RSME (ɛ) deformations depend on the initial structural condition of the alloy, initial phase state upon thermomechanical aging, and time of holding in a hardened state. The obtained values of reversible deformation ɛ (14.5%) and ɛ (5–6%) significantly exceed their conventionally attainable level. The results of investigation allow extension of the possibilities to control the complex of functional properties of the Ti-Ni alloy with shape memory. [ABSTRACT FROM AUTHOR]

The reactions of iron(III) with β-hydroxyethylimino- N, N-diethanoic acid (H2Heida) and dicarboxy-lic acids (oxalic (H2Ox), malonic (H2Mal), and succinic (H2Suc)) are studied using the spectrophotometric method. The equilibrium pattern in the binary and ternary systems is investigated. The complexation processes were shown to be complicated by hydrolysis and to depend strongly on the acidity of the medium. The following complexes were detected: FeHeida+, Fe(OH)Heida, Fe(OH)2Heida–, Fe(Heida)Ox–, Fe(OH)(Heida)Ox2–, Fe(OH)2(Heida)Ox3–, Fe(Heida)Mal–, Fe(OH)(Heida)Mal2–. Logarithms of the stability constants of these complexes calculated at μ= 0.1 (NaClO4) and T = 20 ± 2°C are equal to 11.64 ± 0.05, 22.97 ± 0.05, 31.17 ± 0.05, 18.83 ± 0.03, 28.27 ± 0.02, 36.14 ± 0.02, 17.64 ± 0.03, and 26.39 ± 0.03, respectively. [ABSTRACT FROM AUTHOR]