No abstract available

[en] The flash temperatures of monoatomic alcohols of aliphatic series at various concentrations of nitrogen oxide vap ours in air have been determined. The decrease in the flash temperature of alcohols is assumed to depend on formation of more highly inflammable compounds in the gas phase. An empirical equation has been proposed for estimating the flash temperatures of aliphatic alcohols as a function of their boiling temperature and concentration of nitrigen oxides in air. Calculations according to Antuan equation has been conducted to evaluate the value of vapour pressure of alcohols of aliphatic series. Evaluation of behaviour of various materials in contact with air, contaminated with vapours of nitrogen oxide is of interest in connection with nitrogen oxide application in nuclear power engineering

[en] The experimental results are reported for self-ignition temperature of electric insulation polyethylene and polyvinylchloride-based cable sheaths in dependence on pressure (concentration) of nitrogen oxides vapours and oxygen range from 0,1 up to 0,7 MPa. The comparison with self-ignition temperature of such materials in oxygen at the same parameters has been conducted. It has been established that the presence of nitrogen oxide vapours decreases the self-ignition temperature of the studied materials. Significant gas emission is another feature of combustion of the studied materials in nitrogen oxides. The decrease of self-ignition temperature in nitrogen oxide vapours requires unique approach in selection and utilization of nonmetal structural materials in this medium from the point of view of their fire hazards

[en] Short communication

[en] Certain methods are examined of optimizing periodic interrogation of sensors connected in a definite sequence to device for data processing in a system for controlling production processes. It is shown that in designing multiinput radioisotope measurement systems with a centralized data processing, the choice of the method of organizing periodic interrogation should be made with account for the conditions existing in each specific case

[en] Possibility of measuring mean height of surface roughness, using γ-radiation, reflected from rough surface, is considered. The problem of measuring mean height of surface roughness is reduced to determination of mean square deviation value σsub(x)sup(2). Algorithm of σsub(x)sup(2) determination is described in detail; evaluations of mathematical expectation and dispersion are used in it. It is stated, that σsub(x)sup(2) error depends on anti x value, and it decreases with the growth of measuring point number. Evaluation of approximated expression for σsub(x)sup(2) dispersion has shown, that at 6% error of measuring roughness mean square deviation, summary measuring time of 200 s order at 0.1 s duration of one measurement and mean counting rate of about 10⁵ pul/s is required

[en] In operation of stands and plants using nitrin as a coolant their safety in terms of electricity depends on conditions of cable systems which in certain conditions are likely to be affected by the nitrogen oxide vapors. The compatibility of oxide coatings of electric cables with nitrogen oxides has been investigated. It is shown that the coatings on the base of sterene, divinyl and isoprene rubbers in contact with nitrogen oxide acquire sensitivity impact which increases with the increase of the oxides contents in ambient air and which is due to oxides sorption by the coating surface and to deeper processes of nitration of the rubber components are subjected to destruction and oxidation in consequence of which their application in such conditions is limited. However when atmospheric pollution is possible only in accidents one can allow the application of cables under conditions of their chemical treatment and tests for defects of electroinsulating coating according to their physical and mechanical properties

[en] A plant allowing the behaviour of a variety of materials to be studied under the simultaneous effect of ionizing radiation and corrosive gaseous media is described. The investigation of the effect of gamma-radiation with various dose rate on the origin of sensitivity of rubbers to impact at contact with air containing N₂O₄ vapours has been conducted at the plant. The investigations basically demonstrate experimental possibilities of the plant, which allows to study variations in physical, chemical and mechanical properties of rubbers under the separate and simultaneous effects of corrosive gaseous media and ionizing radiation depending on time of contact, temperature, dose rate and value of the absorbed dose

[en] The compatibility of electric cable sheaths on polyethylene and polyvinylchloride base with nitrogen tetroxide has been studied. It is shown, that the cables with polyethylene sheaths are compatible with N₂O₄ and can be used in the conditions of the contact with it within 5 hours. Polyvinylchloride is incompatible with nitrogen oxide and polyvinylchloride based cables can be used only with oxides concentraton don't exceeding 0,5 g/l. Under the effect of high concentrations before dismounting or conducting works after accidents, these cables need special treatment for eliminating impact sensitivity acquired in the conditions of contamination

[en] An experimental setup is described used to investigate the pd-ppn reaction on a 650 MeV proton beam. Products of the reaction under investigation are detected by scintillation counters and filmless spark chambers. A high-voltage pulse delay of 130 ns has provided the track detection efficiency as high as 98%. The setup operates on-line with the Minsk-22 and HP 2116C computers