Composition and Structure of Films Formed in Etching of Nickel in a Ni(NO3)2 Solution with NiCl2 and NaNO2 Additives

The composition and structure of films formed in etching of nickel in a Ni(NO₃)₂ solution in the presence of Cl^- and NO₂ ^- ions was studied.     

ESR spectra of γ-irradiated samples of iron(iii) binuclear complexes

-Irradiation of -oxo-bridged binuclear iron complexes Fe^III ₂OL _n in a glycerol or dimethylformamide matrix at 77 K affords unstable mixed-valence Fe^IIF^III forms resulting from the transfer of a mobile electron generated by the ionizing radiation. These nonequilibrium forms retain the ligand environment of the original complexes, and their ESR spectra at 77–200 K are characterized by an asymmetric signal with an axially anisotropicg-factor, which is in agreement with the spectra of the Fe^IIFe syu forms obtained by chemical reduction.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 869–871, April, 1996.     

Radiolysis and photolysis of crystalline 2,4,6-triazido-3,5-dichloropyridine: Generation of Quintet dinitrenes

Low-temperature radiolysis and photolysis of crystalline 2,4,6-triazido-3,5-dichloropyridine (TAP) were studied by means of the ESR technique. It was found that the long-term irradiation of TAP at 77 K leads to the appearance of characteristic signals of quintet 2,6-dinitreno-4-azido-3,5-dichloropyridine and 2,4-dinitreno-6-azido-3,5-dichloropyridine; their radiation-chemical yield was 0.035 and 0.012 molecule/100 eV, respectively. The photolysis of crystalline 2,4,6-triazido-3,5-dichloropyridine proceeded less effectively, producing only quintet 2,6 dinitrene with a quantum yield of ～4.5 × 10^?4. The study showed that the generation of high-spin nitrenes via radiolysis of crystalline azides is much superior to the photochemical technique in efficiency and may be of practical importance for the preparation of magnetically active organic materials.     

Supramolecular Conformational Effect in Complexations of Pectin and Chitosan Polysaccharides with Some Cephalosporin and Aminoglycoside Antibiotics

The reactions of the polysaccharides pectin (Pc) and chitosan (CTS) with antibiotics of cephalosporin and aminoglycoside series were studied. The complexation between the drugs and polymers was found to occur via hydrogen bonding. Dilution of the chitosan polycation increased the probability of occurrence of the negative ions of the cephalosporin antibiotic near the chain and lowered the probability of occurrence of the positive ions of aminoglycoside antibiotics, which affected the amount of adducts. When the pectin polyanion was diluted, the opposite situation was observed.     

Biologically Active Coordination Compounds of Germanium. Synthesis and Physicochemical Properties

Russian Journal of Organic Chemistry - A promising area of modern coordination and supramolecular chemistry is the synthesis of biologically active compounds of germanium and creation of effective...     

Tetrafluoroethylene telomerization initiated by benzoyl peroxide

The radical telomerization of tetrafluoroethylene initiated by benzoyl peroxide (BP) photolysis at λ ≥ 365 nm is studied in acetone, dichloromethane, carbon tetrachloride, and Freon 114B2 at 25°C. The products of synthesis are a mixture of telomers of different molar masses, segregated into soluble and insoluble fractions. To characterize the radicals initiating telomerization, crystalline BP and its solution in ethanol are subjected to low-temperature (77 K) photolysis, with the liquid system serving as a model for BP behavior in solutions of telogens. It is established that radicals are not only initiators but also participate in chain termination reactions, lowering the telomers’ molar mass and thus raising the proportion of the soluble fraction. Telomerization initiated by an initiator compound versus initiation by gamma radiation are compared and discussed.