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The oxidation process of samariumoxysulfide was studied in the temperature range of 500−1000 °C. Our DTA investigation allowed for establishing the main thermodynamic (∆Hºexp = −654.6 kJ/mol) and kinetic characteristics of the process (Ea = 244 kJ/mol, A = 2 × 1010). The enthalpy value of samarium oxysulfate (ΔHºf (Sm2O2SO4(monocl)) = −2294.0 kJ/mol) formation was calculated. The calculated process enthalpy value coincides with the value determined in the experiment. It was established that samarium oxysulfate crystallizes in the monoclinic symmetry class and its crystal structure belongs to space group C2/c with unit cell parameters a = 13.7442 (2), b = 4.20178 (4) and c = 8.16711 (8)Å, β = 107.224 (1)°, V = 450.498 (9)Å3, Z = 4. The main elements of the crystalline structure are obtained and the cation coordination environment is analyzed in detail. Vibrational spectroscopy methods confirmed the structural model adequacy. The Sm2O2SO4luminescence spectra exhibit three main bands easily assignable to the transitions from 4G5/2 state to 6H5/2, 6H7/2, and 6H9/2 multiplets.

Chromosome numbers (2n) are counted for 17 species (11 families) in the Far East of Russia, where Hemerocallis coreana (2n = 22) is studied for the first time.

Anatomical structure of petioles of five taxa of the genus Dasiphora is described. Far Eastern representatives are well distinguished by the shape of petiole cross section. Polymorphic species D. fruticosa reveal variability in the shape of petiole cross section which correlates with different growing conditions. All studied taxa differ in their petiole anatomy

Chromosome numbers (2n) are presented for 16 species from 7 families of Primorye Territory. Of these, chromosomes are counted for the first time for Aconitum сoreanum (2n = 32, 2n = 32 + 2B) and a new chromosome number for Allium anisopodium (2n = 32) is revealed. Images of metaphase plates are given.