Purpose. Rail transport is one of the safest types of transportation, however, train accidents and catastrophes entail loss of life and significant property damage. A topical issue is the uninterrupted fire suppressant supply in case of fires on the railway. The authors present the results of an experiment on the development of a connecting device prototype to extend high-pressure hoses during firefighting. Methods. The authors have applied a comprehensive analysis of situational factors on the basis of practical experience in conducting fire extinction, preliminary planning and descriptions of the operational situation at a fire scene. The simulation of fire unit actions in extinguishing a fire on the route between stations has been carried out. Tests of the developed sample, a connecting device for high-pressure hoses, have been carried out as well. Findings. The authors have determined a significant degree of influence of fire unit actions on the effectiveness of performing the major combat mission, as well as the possibility of using the optimized management task route by the Fire-Ground Commander. The author team has developed a connecting device prototype to extend high-pressure hoses during fire fighting. Research application field. The study results are aimed at rationalizing the fire extinguishing process and organizing management to perform the main combat mission on the infrastructure of rail-type transport. The results can be applied to improve the forces of units involved in performing the main combat mission, increase the training facilities and capacities of Fire Service and introduce fire protection educational institutions into the process of training as well. Conclusions. The results of the experiment on the development of a connecting device prototype to extend high-pressure hoses during fire fighting in hard-to-reach places are presented. An algorithm for using a high-pressure hose in railway transport is proposed. It will allow reducing the consumption of a fire extinguishing agent relative to normal pressure hoses and increasing the distance for its use.
The well-known electrostatic energy analyser of charged particles, so-called "Spherical Mirror Analyser" (SMA) has been examined. A new regime of its working is found, very suitable for coincidence spectroscopy. Angular distribution of the particles emitted from the point source is recorded simultaneously on the surface of a position sensitive detector (PSD), while energy resolution, not worse than 0. 1%, is achieved due to the dependence of the time of flight of the particles on their energy.Keyword list: energy and angular analysis, electron coincidence spectroscopy, focusing in time, axially symmetric analyser, luminosity, time of flight, position-sensitive detector. LNTORDUCTIONThe methods of electron coincidence spectroscopy (ECS) allow detailed and deep understanding the physical processes taking place inside the atomic and electron structure of solids. For instance, Auger Photoelectron Coincidence Spectroscopy (APECS) makes it possible to separate different Auger ionization events, such as shake-up or shake-off ones1 . It gives rise to studying different Auger processes and complete interpretation of the observed lineshapes2.In ECS, two analysers are to record, with energy resolution, two different charged particles born simultaneously in the same elementary act. To separate these true> coincident particles from random coincidences, very good timing resolution T is necessary, not worse some nanoseconds3. As the intensity of the recorded particles is extremely low, the demand arises for two conditions to be fulfilled simultaneously: a) Angular focusing: particles of the same energy should pass through the exit diaphragm, no matter in what direction they were emitted. b) <
Methods of nondestructive remote monitoring of the elemental composition of an object by determining the nuclear-physical parameters of the material (monitoring of freight during transport, well-logging, and so on) are now widely used in practical work. Such methods are especially important for analyzing the content of fissioning substances and, in connection with nuclear disarmament, for monitoring nuclear weapons [1]. In the latter problem, special difficulties have appeared in the development of physical methods of remote monitoring (inspection) of a nuclear weapon, for which only active methods can be used [2]. In the present paper we present some experimental results indicating that the new remote active method of identification of substances can be successfully used.The method includes measurement of the time dependence of the spectrum of -/-radiation emitted by the object being investigated after it was irradiated with a short neutron pulse. The energy and time characteristics of the -/,/-radiation are used to identify the elemental composition of the object. The time scale of the process is determined by the lifetime r of the neutrons in the object, 7" being of the order of hundreds of nsec. For this reason, the duration tp of the neutron pulse must be much shorter, for example, tp -10-30 nsec. When fissioning materials are present, 7" should increase as a result of the neutron-multiplication properties of the medium. This can already be used to identify fissioning substances [3]. The -/-rays emitted by the object are registered within a time At -7" with a detector placed at a large distance from the object (this makes it possible to separate the -/-rays from the neutrons), and in the process both the arrival time T of a -/-ray relative to the start of each neutron pulse and the amplitude A of the pulse are recorded. Therefore, the result of the measurements will be a matrix [T, A], where T is the time in the time converter-code channels or time units; A is the amplitude in the charge conversion-code channels or energy units.The energy spectrum of the -/-rays arriving at the detector at each time T is a complicated function of the macroscopic cross sections for the interaction of neutrons with the target material, the target geometry, the duration and dimensions of the neutron beam, and the energy of the primary neutrons. Moreover, if the neutrons are formed by means of proton or deuteron accelerators in the outer layers of the substance of the object itself or in the direct proximity of the object, then during the action of the pulse -/-rays from the reactions (pn) or (dn) are present. Under unfavorable conditions the measurements can also be influenced by the external -/-ray background. For this, we proposed recording the -/-ray spectrum after the matrix [T, A] is processed during the time At -100-300 nsec after the primary-neutron pulse. It is significant that when fissioning substances are present, the delayed fission -/-rays [4], whose intensity is about 6% of the prompt fission -/-rays, fall within ...
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