[en] A new method of investigation of spatial structure of biological macromolecules and their complexes - tritium planigraphy - was considered. The method is based on the determination of the studied object fragments, sterically attainable for tritium hot atoms, and it provides information on its accessible surface, which in its turn is the function of spatial structure. Tritium hot atoms with the energy of 0.35-1.5 eV are produced via thermal atomization of molecular tritium on tungsten filament heated up to approximately 2000 K. Radioactivity of lithium-labelled product characterizes the number of primary acts with participation of hot particles. Results obtained using tritium planigraphy, when studying the structure and conformation transitions in proteins, as well as results of the study of spatial arrangement of viruses, are discussed

[en] High secondary emission properties at comparatively low operation temperatures were obtained when investigating aluminum-lithium alloy Al - 2.2 mass % Li. The maximal value of the coefficient of secondary electron emission for alloy, activated under optimal conditions, is achieved at comparatively low energy of primary electrons, equal to 600 eV. Low value of the first critical potential (15 ± 2 eV) was obtained. It is important for operation of secondary emission cathodes. 12 refs.; 4 figs

No abstract available

[en] Absorption of hydrogen by alanine targets, the target behaviour and the yield of α-alanine-³H were studied in experiments involving straight passage of H and T atoms from the sourse (2000 K) to the target (77 K) as a function of the exposure time. In the studies with ³H₂ the radioactivity of the gas phase was decreasing more rapidly than the overall pressure of hydrogen: H³H accumulates more rapidly in the gas phase. Alanine decomposition products were identified. The conditions for the studies of α-alanine-³H are suggested

[en] A method of tritium introduction into preparation of organic substances of different clases based on the use of atomic tritium is considered. An organic target ''is irradiated'' by a flux of tritium atoms with the temperature of 2000 K. At such energies atoms easily interract with substance and substitute hydrogen for tritium in it as a result of consequence of hydrogen separation and ³H atoms recombination processes and appearing free radicals. Low temperature of the target (usually 77 K or lower) conditions a high degree of target preservation. Preparations obtained are easily separated in the pure form by conventional method, such as chromatography and achieved specific activities (10-30 Ci/mmol) are sufficient to solve most problems set for investigation. The possibilities of the method are illustrated on a number of preparations of various complexity. Biologic tests have established that not only chemical structure of the labelled substance but also specific biological activity preserves as well

No abstract available

[en] The products and intramolecular distribution of tritium have been studied in the reactions of tritium atoms, obtained upon catalytic dissociation on incandescent tungsten, with D(α)-alanine. The main by-product is propionic acid whose yield is 60% of that of alanine. Intramolecular distribution of tritium in alanine corresponds to 88% of tritium in α- and 12% in β-position. The mechanism of ''label'' introduction is proposed

No abstract available

No abstract available

No abstract available