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The purpose of this paper is the assessment of the FA pin-by-pin model available in the KORSAR/GP code. The paper presents the results of the simulation of an “Control rod ejection” accident. This accident is of interest due to the power redistribution in the FAs effected by the ejection. The safety margins are calculated with the use of the “hot channel” model for NPP safety analyses. Only the fuel rods of the core with the highest power are taking into account. The absence of the change of the pin power distribution for the FA during the transient is compensated by increased conservatism. In this paper, the maximum fuel rod power was obtained using the pin-by-pin model.

The results of the development and investigation of the properties of transparent bactericidal two-component oxide coatings based on TiO_2-ZnO and TiO_2-MgO on glasses are presented. It is established that the coatings consist of oxide nanoparticles with uniform sizes (10–15 nm) that are characterized by high transparency in the visible region of the electromagnetic spectrum. It is shown that two-component oxide coatings exhibit better bactericidal properties compared to their single-component analogs.

This work deals with TRAP-KS code verification. TRAP-KS is used for coupled neutron and thermo-hydraulic process calculations of VVER reactors. The three-dimensional neutron kinetics model enables consideration of space effects, which are produced by energy field and feedback parameters variations. This feature has to be investigated especially for asymmetrical multiplying variations of core properties, power fluctuations and strong local perturbation insertion. The presented work consists of three test definitions. First, an asymmetrical control rod (CR) ejection during power operation is defined. This process leads to fast reactivity insertion with short-time power spike. As second task xenon oscillations are considered. Here, small negative reactivity insertion leads to power decreasing and induces space oscillations of xenon concentration. In the late phase, these oscillations are suppressed by external actions. As last test, an international code comparison for a hypothetical main steam line break (V1000CT-2, task 2) was performed. This scenario is interesting for asymmetrical positive reactivity insertion by decreasing coolant temperature in the affected loop.

A conceptual approach is proposed to determining the minimum achievable number of control organs in the safety and control system and the minimum effectiveness of emergency shielding of VVÉR reactors. This approach includes a new probabilistic method of determining the effectiveness of emergency shielding with failures of different numbers of control organs and a decrease in the excess conservatism in performing thermohydraulic analysis. The modern safety ideology is used. For VVÉR-1000, it is shown that emergency shielding with 49 control organs is sufficient for the determining anticipated accident with steam-pipe rupture.A conceptual approach is proposed to determining the minimum achievable number of control organs in the safety and control system and the minimum effectiveness of emergency shielding of VVÉR reactors. This approach includes a new probabilistic method of determining the effectiveness of emergency shielding with failures of different numbers of control organs and a decrease in the excess conservatism in performing thermohydraulic analysis. The modern safety ideology is used. For VVÉR-1000, it is shown that emergency shielding with 49 control organs is sufficient for the determining anticipated accident with steam-pipe rupture.

New possibilities for an improved MEX approach and program are presented. It is shown that the following positive fundamental benefits are feasible: - the formation of a perturbed power distribution over the fuel elements and a perturbed total power of a fuel assembly and power distribution of real fuel elements; - more cost-effective fuel arrangements in the core and the fuel assemblies or an increase in the power of the core; - better justification for the choice of the initial conditions in deterministic and probabilistic analyses.

1.Both theoretically and practically it is quite possible to obtain a capacitor with an effective negative loss angle or without a loss angle by means of three actual capacitors with actual losses connected according to the circuit shown in Fig. 1b, although in practice such conditions arise only in very rare special cases.2.When a three-terminal loss-free capacitor is designed it is necessary to adhere to the following rules.

1.Study of Yarega petroleum revealed that it contains unsaturated hydrocarbons.2.The fractions of Yarega petroleum boiling below 275‡C have unsaturated hydrocarbon contents of 0.8%.

A range of thermal viewers based on an uncooled microbolometer array (λ=8-14μm) is described. The results of full-scale experiments are given.