Mechanism of the decomposition of cobaltous compounds in vacuo

The decomposition of cobaltous compounds (nitrate, hydroxide, carbonate, oxalate and oxyhydroxide) in vacuo has been investigated by magnetic methods and thermogravimetry. The mechanism is shown to be similar to that in air and begins with the formation of Co³⁺ ions in octahedral coordination. The formation of different final products (Co₃O₄, CoO and Co) has been attributed to the nature of the initial cobaltous compound. The results are in agreement with thermodynamic calculations.     

The use of solid-state nuclear track detection for the study of boron and fissile nuclide distributions in steel samples

The technique of boron autoradiography using cellulose acetobutyrate (CAB) film for measuring the distribution of boron in stainless steels, is described. The method involves the irradiation of the specimen and detector with thermal neutrons, and the development of the α-particle tracks arising from the nuclear reaction¹⁰B(n, α)⁷Li. A related technique for the measurement of fissile nuclides in steel hulls, is also described. In this case, a polycarbonate detector, Lexan, is used to detect the fission-particles from the thermal neutron fission of²³⁵U or²³⁹Pu, present in the surfaces of the specimens. The principles of the methods are described, and an outline of the techniques presented. The quantitative aspect of the method is considered and the results on various specimens discussed.     

Semiempirical calculation of photoionization cross sections for the first excited levels of F I

Radial matrix elements and photoionization cross sections have been calculated for all levels of the first excited configuration 2p ⁴(³ P) 3s of neutral fluorine as an example for the application of the Scaled Thomas-Fermi method. The extrapolation of empirical data on energy levels to positive electron energies and the reliability of the method are discussed.     

Regiospecific synthesis of 11-desoxyanthracycline antibiotics starting with aloe-emodin

The regiospecific synthesis of an established 11-desoxyanthracycline synthon ($\text{8b}$) from aloe-emodin ($\text{3a}$) is described.     

Hyperpolarizability approximations

The approximation of hyperpolarizabilities through the use of operator inequalities is sketched. Previously applied methods to ordinary polarizabilities are extended. They lead to expressions involving moments of oscillator strength distributions related through sum rules to ground state properties. Systematic applications of new formulae are suggested.     

New polymer-supported catalysts. (Polyvinylchloride-containing redox) catalyst cyclopentadienyl iron moiety: [η5C5H5Feη6C6(CH3)5CH2?]+

New polymer-supported catalysts that contain the redox cyclopentadienyl iron moiety [η⁵C₅H₅Feη⁶C₆(CH₃)₅CH₂? ]⁺ were prepared with polyvinylchloride (PVC) as support. The active center is attached as a pendant organometallic moiety in the side groups of the PVC chain. Metallocenic groups and the supported polymers with various Fe content were analyzed by spectroscopic techniques and by polarographic and cyclic voltammetry. The absorption spectra show a similar profile to that of the nonsupported cation, which indicates that the supported polymer contains side groups in the chain with metallocenic structures. The new polymer-supported catalysts were characterized by viscometric measurements and by differential calorimetry (DSC). A linear relationship between intrinsic viscosity/[η] and the Fe content was observed. The glass transition temperature (T_g) values are higher than those of PVC without modification.     

Thin-film antimony trisulphide photoelectrodes

The properties of n-type thin polycrystalline films of antimony trisulphide obtained by tarnishing reactions have been studied by photoelectrochemical and spectroellipsometric techniques. The photoelectrochemical behaviour is analysed using a recombination model.     

Structure of “furfuramide” and “furfurine”

The structures of ,-bis(furfurylideneimino)silvan (furfuramide or N,N'-difurfurylidene-2-furanmethanediamine) and the product of its thermal cyclization 2,4,5-tris (-furyl)-2-imidazoline (furfurine) were confirmed by comparison of the IR, UV, ¹H and ¹³C NMR, and mass spectra. It is shown that acetylation of the latter with acetic anhydride in the case of heating of the reagents without a solvent or in pyridine takes place with opening of the imidazoline ring and leads to the formation of 1,2-bis(-furyl)-1-acetamido-2-(-furoylamido)ethane.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1461–1464, November, 1978.     

Synthesis of s-triazolocycloalkyl-, s-triazolobenzocycloalkyl-, and s-triazolocycloalkylhydrothiadiazines

The reaction of cyclic-α-haloketones with 5-subslituted-4-amino-4H-1,2,4-triazole-3-lhiols gave s-triãzolocycloalkylhydrothiadiazines and s-triazolobenzocycloalkylthiadiazines. Reduetion of the 5,5a-imine bond of the s-triazoloeycloalkylthiadiazines gave s-triazolocycloalkylhydrothia-diazines.     

Kinetic study and analytical application of the iodate-hypophosphite reaction in strongly acidic solutions

The iodate—hypophosphite reaction in strongly acidic solutions was studied spectrophotometrically. Reaction rate constants and the activation energy of the reaction are reported. A method for determining hypophosphite on the basis of this reaction is described. Hypophosphite in the range 0.06–4 mg (10^-3–6·10^-2 M) can be determined with a relative error and relative standard deviation of 2—3%.