New example of the enamine rearrangement of pyrimidines

Erevan Institute on the National Economy, Erevan 375025. Translated From Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1577–1578, November, 1995. Original article submitted november 29, 1995.     

Photocatalytic Inactivation of Bacteria in the Presence of Tungsten-Modified Titania under Visible Light Irradiation

Kinetics and Catalysis - Photocatalytically active materials based on titania modified with tungsten (5–30 wt %) have been synthesized. Specific features of the formation of these materials...     

Kinetics of the deactivation of the vibrations of highly excited oscillators in an inert gas medium,taking account of spontaneous radiation

In the diffusion approximation, the article discusses the kinetics of the process of deactivation of the vibrations of radiating anharmonic and harmonic oscillators in an inert gas medium. Limiting solutions are given for the purely radiational deactivation of a classical Morse oscillator and of a harmonic oscillator. It is shown that, with an increase in the effect of spontaneous radiation, the role of the anharmonic character of the vibrations in the process of deactivation increases; the initial (or arbitrary) distribution relaxes more slowly the higher its energy level, i.e., the greater the effect of the anharmonic character of the vibrations. The results are of importance for systems with a considerable population of the upper vibrational levels of the molecules, which may arise as a result of a chemical reaction or by the optical pumping of a gas.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 62–67, July–August, 1972.The author thanks N. N. Magretova for carrying out the numerical calculation.     

Synthesis of tetracyclic thienotriazolopyridines based on hydrazine derivatives of fused pyridinethiones

A method for the synthesis of hydrazine derivatives of fused pyridinethiones based on alicyclic and heterocyclic ketones has been developed. Successive heterocyclization of these hydrazine derivatives was carried out in order to obtain new derivatives of tricyclic triazolo[4,3-a]pyridines, tetracyclic thieno[3,2-e][1,2,4]triazolo[4,3-a]pyridines, as well as a new heterocyclic system of thieno[2,3-c][1,2,4]triazolo[3,4-a]-2,7-naphthyridine.

     

On the theory of vibrational relaxation of diatomic molecules

The relaxation of diatomic molecules (harmonic oscillators) in a relatively light inert gas, which plays the part of a thermostat, is considered within the framework of classical mechanics. The gas-kinetic equation for the distribution function of diatomic molecules is approximated by the Fokker-Planck equation in the space of the energies of translational, rotational and vibrational motions on the assumption of strong nonadiabaticity of the collisions. In the approximation discussed, relaxation processes with different degrees of freedom develop independently, although the characteristic times of these processes are quantities of the same order. The vibrational relaxation time, expressed in terms of the gas-kinetic integral ^*(1,1) (T*), is obtained.