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The results of radiation tests are discussed and the character of the failure of fuel compositions and the operability of fuel elements is analyzed as a function of the type of fuel and the irradiation conditions. The intense interaction of the fuel with the matrix material is considered as the main factor limiting the operability of fuel elements in power-dense high-flux nuclear reasearch reactors. It is concluded that low-enrichment high-density uranium-molybdenym fuel can provide reliable operation of dispersion fuel elements in low-and medium-power research reactors. Such fuel can be used in power-dense high-flux research reactors if the fuel load is decreased below the maximum admissible amount, the compatibility of the uranium-molybdenum alloy with an aluminum matrix is radically improved, or fuel elements with a different construction, for example, monolithic, are used.A large number of radiation tests of new types of dispersion fuel have been conducted as part of the international program on decreasing the enrichment of fuel for research reactors (RERTR) and national programs [1][2][3][4][5]. Plate-shaped miniscale fuel elements with dispersion fuel based on various high-density alloys and uranium compounds have been tested at the first stage. Fuel based on uranium silicide U 3 Si 2 and uranium alloys with 7-10% molybdenum or zirconium and niobium with total content at least 10% exhibited the best radiation resistance. Consequently, mini-and full-scale fuel elements with fuel based on these alloys, primarily, uranium alloys with molybdenum (here and below, the mass fraction of the alloying element is given in %) were tested in further tests.The influence of the characteristics of the dispersion fuel and the conditions of irradiation on the radiation resistance of fuel elements were investigated in the experiments. The results obtained make it possible to draw conclusions about the regularities in the behavior of, the failure of fuel compositions of, and the operability of fuel elements as a function of the type of fuel and conditions of irradiation.Results of the First Stage of the Investigations. At the first stage of the investigations, the RERTR-1 and -2 computer programs were used to study the radiation resistance of plate-shaped miniscale fuel elements with fuel based on intermetallic compounds of uranium with iron, manganese, silicon, and aluminum and alloys of uranium with molybdenum, zirconium, and niobium. The uranium content in the composition was 4 g/cm 3 , the heat flux and temperature of the fuel-element cladding were 55 W/cm 2 and 65°C, respectively, and the burnup 40 and 70% 235 U.Some of the fuel elements successfully withstood the tests -they remain sealed, and the increase in the thickness of the plates was negligible. The microstructure of the fuel composition of such fuel elements after irradiation in the reactor was essentially identical to the initial microstructure (Fig. 1). The fuel particles retained their shape and size. The interaction of

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Research on facts and circumstances of electrical energy uncounted consumption in the practice of conducting electrical engineering forensic examination is one of the most common. Study of the influence of a permanent magnetic field on operation of the electromechanical electricity meters is one of the areas of electrical engineering research, where scientific and practical analysis is absent in electrical engineering forensic examination. The tasks solved by electrical engineering forensic examination of electricity meters subjected to interference in their work due to the influence of an external permanent magnetic field are still being solved indirectly, mainly by examining the state of indicators of the effect of a magnetic field. The Article purpose is to determine the mechanism of interference in the operation of a stepper motor of electromechanical electricity meters of energy accounting meters under the influence of an external magnetic field artificially developed to disregard the consumption of electric power. The article examines the structure of a stepper motor of electronic-mechanical devices metering electric power. A research model of a stepper motor is built. The analysis of distribution of force magnetic lines in the magnetic system and in the magnetic shield of a stepper motor as a result of influence of an external magnetic field artificially created for the purpose of uncounted consumption of electric power in the absence of such an effect on the basis of modeling with the use of software and a mathematical apparatus: the finite element method. The mechanism of interference in the regular operation of a stepper motor of electricity meter is determined when approaching the metering device of an external permanent magnet with a high value of maximum specific energy in order to consume electric power negligently.