Investigation of the reduction of methylenequinones by methods of polarography and EPR spectroscopy

Conclusions The polarographic reduction of certain methylenequinones was studied, and the mechanism of the reduction was investigated by the method of EPR spectroscopy.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1656–1658, July, 1970.     

Determination of enthalpies of formation of organic free radicals from bond dissociation energies 2. Halosubstituted radicals

The enthalpies of formation (ΔH _f ^o) for 23 halosubstituted radicals were determined from the published data on bond dissociation energies. The ΔH _f ^o values of the corresponding molecules necessary for the calculation of ΔH _f ^o of the radicals were taken from handbooks or calculated by the additive-group method. The conjugation energies of the radicals are calculated, and the effect of substituents at the π-system on these values was shown. Errors of determination of the ΔH _f ^o values of the radicals were estimated. For Part 1, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 643–646, April, 1998.     

Meldrum's acid and its analogs

2-Substituted or 2,2-disubstituted 4,6-dioxo-1,3-dioxanes, which are analogs of Meldrum's acid and were obtained by reaction of malonic acid with acetic anhydride and the appropriate carbonyl compound in the presence of sulfuric acid, exist in solution preferably in a single form according to the PMR and ¹³C NMR spectral data. Fluctuation of the CH₂ group is not observed. The mass spectra are characteristic and are distinguished by splitting out of the carbonyl compound from the molecular ion or successive splitting out of CO₂ and ketene molecules. The Meldrum acid analogs do not affect plant growth but have a depressive effect on the central nervous system of animals and low toxicity.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1482–1486, November, 1975.     

Catalytic effect of nickel cyanide complex and skeletal nickel on addition of hydrogen to 6-methyl-3,5-heptadien-2-ol

Russian Chemical Bulletin -     

Activation Analysis Methods and Applications

Summary INAA was applied for searching more effective biosorbents for U and Ag among 9 and 47 strains of actinomyces, respectively. Biomasses of strains were tested for the Ag and U sorption capacity from model solution, containing 50 mg/l Ag ions and from technological solution of U-production, containing 7.11 mg/l U ions. The U and Ag samples were irradiated for 5 hours and 20 hours, respectively, at a neutron flux density of 5.3 ^. 10¹³ n ^. cm^-2 ^. s^-1. The Ag content was calculated from the gamma-line of radionuclide ^110mAg (T_1/2 = 250.4d, E_γ= 657.7keV). The U content was calculated from the gamma-lines (228.2 keV, 277.8 keV) of radionuclide ²³⁹Np (T_1/2 = 2.35 d). The error of U and Ag determination (relative standard deviation) was 2-3%.