Effect of wind uplift of radioactive dust from the ground on the contamination of the atmosphere above the territory of Russia

The character of the time variation of the average yearly concentration of¹³⁷Cs in the near-ground atmosphere of the USSR and Russia in 1954–1999 as well as the special features of the yearly variation of the average monthly concentration in 1981–1985 after the last nuclear explosion in the atmosphere (1980) are examined. The role of wind uplift of radioactive dust from the ground in contamination of the air near the ground by¹³⁷Cs after powerful nuclear explosions in the atmosphere were discontinued and after the Chernobyl accident in 1986 is discussed. It is shown that in the last few years the¹³⁷Cs concentration in the air at the ground is almost completely due to wind uplift from the dry ground and advection on a global scale. The coefficients of wind uplift and deflation, the velocity of wind uplift, and the size of aerosol particles-¹³⁷Cs carriers—are estimated. 3 figures, 14 references. Scientific and Industrial Association “Taifun”. Translated from Atomnaya énergiya, Vol. 88, No. 6, pp. 458–464, June, 2000.     

Experimental study of the characteristics of the flow in the first rows of tube banks

This paper presents the experimental study of the flow instabilities in the first rows of tube banks. The study is performed using hot wire anemometry technique in an aerodynamic channel as well as flow visualizations in a water channel. In the wind channel three tube banks with square arrangement and pitch to diameter ratios P/D = 1.26, 1.4 and 1.6 were studied. The Reynolds number range for the velocities measurements, computed with the tube diameter and the flow velocity in the narrow gap between tubes was 7 × 10⁴–8 × 10⁴. Continuous and discrete wavelets were applied to decompose the velocity results, thus allowing the analysis of phenomena in time–frequency domain. Visualizations in a water channel complemented the analysis of the hot wire results. For this purpose, dye was injected in the flow in the water channel with a tube bank with P/D = 1.26. The range of the Reynolds number of the experiments was 3 × 10⁴–4 × 10⁴. The main results show the presence of instabilities, generated after the second row of the tube bank, which propagates to the interior of the bank. In the resulting flow, the three orthogonal components are equally significant. The three-dimensional behavior of the flow is responsible for a mass redistribution inside the bank that leads to velocity values not expected for the studied geometry, according to the known literature. The resulting flow process can be interpreted as a secondary flow which is characteristic of tube banks.     

Evaluation of the parameters of an experimental tokamak fusion-reactor and the influence of the indeterminacy of the plasmaphysical data

Conclusion Analysis using a simplified technicoeconomic model of a tokamak reactor and the procedures of graphic processing of the results allow the regions of the optimum parameters of an experimental minimum-cost reactor with various limitations to be determined. When refined and ignition scalings are taken into account simultaneously and an appropriate optimization is made we get the parameters of the experimental reactor, which differ slightly from the basic variant (in particular, a lower neutron load on the first wall). The reactor cost in this case should increase by 15–25% in comparison with the basic variant and remains virtually constant when the most favorable ignition scaling (ASDEX) is realized.Translated from Atomnaya Énergiya, Vol. 62, No. 1, pp. 22–28, January, 1987.     

Analysis of the possibilities of the neutron-resonance method of determining the elemental composition of matter

Mathematical modeling of the neutron-resonance method analyzing the elemental and isotopic of matter is performed. The method is based on investigation of γ cascades, emitted by nuclei as a result of the radiative capture of neutrons. Gamma cascades of the determined element (effect) and elements of the matrix (background) are modeled and these cascades are detected with a γ-ray multisectional 4π detector. The response functions of the detector are presented for the case of an analysis of the gold content in a natural medium. It is shown that the introduction, performing together with neutron spectrometry, the spectrometry of γ cascades makes it possible to increase the effect/background ratio by a factor of 100. It is noted that this ratio can be further increased by improving the method used to detect γ cascades and analyzing the results of the measurements.     

Electromagnetic Theory of the Binding Energy of the Hydrogen Isotopes

Bieler of the Rutherford laboratory imagined in 1924 a magnetic attraction equilibrating an electrostatic repulsion between the protons. Since the discovery of the neutron and the magnetic moments of the nucleons proving that the neutron contains electric charges, nobody, as far as I know, has tried to apply electromagnetism to the nuclear interaction. As it is well known, there is an attraction between an electric charge and a neutral conductor. In the deuteron, the positive charge of the neutron is repelled and the negative charge is attracted by the proton with a net attraction. The repulsion between the magnetic moments equilibrates the electrostatically induced attraction. The calculated value is −1.6 MeV not too far from the experimental value (−2.2 MeV). The calculated 7 hydrogen isotopes stay satisfactorily along the experimental isotopic parabola. No arbitrary fitting parameter is used, only universal physical constants. The electromagnetic theory predicts a theoretical ratio between nuclear and chemical energies: \fracm_pm_e a.\frac{m_p}{m_e \alpha}.     

Measurement of the Characteristics of the Ventilation Pipe of the Filtration System for the Steam-Gas Medium of a Nuclear Power Plant

The dependence of the heat power of a pipe (air–air heat exchanger) on the flow rate and the temperature of the heating air is investigated experimentally. The temperature fields along the height of the pipe are measured. In the experimental velocity range 1.2–9.5 m/sec and heating-air temperature range 120–280°C, the heat power depends strongly on the temperature and negligibly on the flow rate of the heating air. Increasing the cold-air flow rate increases the thermal power in direct proportion.     

On the generalization of the average chord length

Recently, it has been proved that the well-known mean chord length property remains valid for some diffusive processes in bounded domains. Based on the one-velocity linear Boltzmann transport equation, this result can be extended to spaces of constant curvature. Besides, for straight lines, inequalities for the ray distribution (starting point inside the domain and exiting point on the surface of the object) are derived using simple tools from integral geometry in Rⁿ${\mathbb{R}}^n$.     

A nodal collocation method for the calculation of the lambda modes of the PL equations

P_L equations are classical approximations to the neutron transport equation admitting a diffusive form. Using this property, a nodal collocation method is developed for the P_L approximations, which is based on the expansion of the flux in terms of orthonormal Legendre polynomials. This method approximates the differential lambda modes problem by an algebraic eigenvalue problem from which the fundamental and the subcritical modes of the system can be calculated. To test the performance of this method, two problems have been considered, a homogeneous slab, which admits an analytical solution, and a seven-region slab corresponding to a more realistic problem.     

Comparison of the cracking resistance characteristics of the base metal and the welded joints of reactor vessels

Skoda Industrial Combine, Czechoslovak Federal Republic. Central Scientific-Research Instituteof KM Prometei. Gidropress Experimental Design Office. NIKIÉT. Translated from Atomnaya Énergiya, Vol. 72, No. 3, pp. 246–251, March, 1992.     

Investigation of the properties of the nuclei used on the new generation reactor technology systems

The main application fields of the fast neutrons are accelerator-driven subcritical systems (ADS) and fusion–fission (hybrid) reactor systems for fission energy production. Thorium (Th) and uranium (U) are nuclear fuels in these reactor systems. Lead (Pb), bismuth (Bi) and tungsten (W) are the target nuclei in the ADS reactor systems. The technical design of ADS and hybrid reactor systems require much effort and data. The Hartree–Fock (H–F) method with an effective interaction with Skyrme forces is widely used for studying the properties of nuclei such as binding energy, root mean square (RMS) charge radii, mass radii, neutron density, proton density, electromagnetic multipole moments, etc. In this study, by using H–F method with interaction Skyrme RMS charge radii, RMS mass radii, neutron density and proton density were calculated for the ²³²Th, ²³⁸U, ²⁰⁷Pb, ²⁰⁹Bi and ¹⁸⁴W isotopes. The calculation results of charge radii were compared with experimental data. Obtained RMS mass radii, neutron density and proton density results were discussed for ADS and hybrid reactor systems.     

Metadata on the radioactive contamination of environmental objects on the territories of Russia and the USSR

A unique data archive, accumulated at the Taifun Scientific and Industrial Association in 1954–2005, on the radioactive contamination of the environment on the territory of the USSR and Russia is presented. The archive contains data on the yearly total β activity of atmospheric fallout on the underlying surface, the total volume β activity in the atmosphere at the ground, the results of measurements of the ⁹⁰Sr and ¹³⁷Cs content in samples combined over one month or quarter, atmospheric aerosols and fallout on individual points, the volume activity of tritium and ⁹⁰Sr in water, rivers, lakes and seas, and the radionuclide contamination density of the territories of populated points as a result of the Chernobyl accident. __________ Translated from Atomnaya énergiya, Vol. 101, No. 2, pp. 149–152, August, 2006.     

On the decomposition of the UN-CeN solid solution

The decomposition temperature of CeN, U_0.5Ce_0.5N and U_0.75Ce_0.25N has been measured as a function of nitrogen pressure. The results are , , , where p_N2 is in atm and T in K. Thermodynamic analysis based on the reaction, in which the solid solution, U_1?xCe_xN, decomposes into U_1?xCe_x(1) and $\text{1}\text{2}\text{N}{}_2\text{(g)}$, results in a very simple relation: logp_N2[U_0.75Ce_0.25N] = (1 ? x) logp_N2 [UN] +xlogp_N2 [CeN], where the assumption that the interaction parameters for U_1?xCe_xN and U_1?xCe_x(1) have the same value was made. The influence of solubility of nitrogen in U_1?xCe_x (1) has been also taken into consideration. The present experimental data are in good agreement with the equation derived from the present thermodynamic analysis.     

Optimization of the radiation shielding mass for the magnet coils of the VISTA spacecraft

An attempt has been made for the optimisation of the radiation shielding of a spacecraft design concept with inertial fusion energy propulsion for manned or heavy cargo deep space missions beyond earth orbit. Rocket propulsion is provided by fusion power deposited in the inertial confined fuel pellet debris, and with the help of a magnetic nozzle. The allowable nuclear heating in the super conducting magnet coils (up to 5 mW/cm³) is the crucial criterion for the dimensioning of the radiation shielding structure of the spacecraft. The optimized design reduced the shield mass from 600 tons to 93 and 88 tons with natural and enriched lithium, respectively. The space craft mass was 6000 tons. Total peak nuclear power density in the coils is calculated to be 5.0 mW/cm³ for a fusion power of 17,500 MW. Peak neutron heating density is 2.6 mW/cm³ and peak γ-ray heating density is 2.9 mW/cm³ (all on different points). However, volume averaged heat generation in the coils is much lower, namely 0.30, 0.73 and 1.03 mW/cm³ for neutron, γ-ray and total nuclear heating, respectively.     

Determination of the235U concentration in the aqueous coolant of the first circuit of a nuclear reactor

Conclusions A technique was developed for determining the²³⁵U concentration in the aqueous coolant of the first circuit of a nuclear reactor: detection limit 3·10^–12 g/cm³. Using the method in the IVV-2M reactor has shown that with this technique, an operational monitoring of the uranium concentration in the coolant and in the fluids washed from the surface of the first circuit, as well as monitoring other qqueous samples, is possible.Lavsan, which is directly irradiated in a liquid sample and electrochemically etched, can be recommended as a detector. The optimal conditions of etching 180-m-thick lavsan (after irradiation with thermal neutrons to a flux of (1–2)·10¹⁶ cm^–2) are: 30% aqueous KOH solution, a temperature of (70±0.2)°C, an electric field strength of 20 kV/cm, a frequency of 4 kHz, and an etching time of 100 min.Translated from Atomnaya Énergiya, Vol. 61, No. 5, pp. 334–338, November, 1986.     

Tests of membrane-sorption decontamination of the reservoir cascade of the Techa river

Results are reported from a comprehensive test, under real conditions, of technology for removal of ⁹⁰Sr from the waters of the Techa reservoir cascade. This technology includes stages of preliminary decontamination, ion exchange softening with desorption and carbonate precipitation of hardening salts and ⁹⁰Sr from the desorbates, sorption cleanup on natural zeolites, and concentration of the strontium-containing carbonate precipitates. After the precipitates are removed, the solutions are reused in the desorption stage. The quality of the decontaminated water meets all the requirements for discharge into open drainage network in terms of all indicators. (The specific activity of ⁹⁰Sr is 3–5 Bq/liter in the filtrates.) The ⁹⁰Sr is concentrated by a factor of about 900 as solid radioactive waste in the form of a sediment with a moisture content of 50% and by about 1700 as air-dried solids. As a preliminary estimate, the operating cost of decontaminating 1 m³ of water in the V-11 reservoir is 200 rubles. Translated from Atomnaya énergiya, Vol. 105, No. 5, pp. 278–285, November, 2008.     

Taking account of the effect of the curvature of VVÉR-1000 fuel assemblies on the power of the fuel elements

A comparative analysis is made of the deterministic and statistical methods of taking into account the effect of the curvature of VVéR-1000 fuel assemblies on the power of fuel elements. The fuel-element distribution of the energy release in the core for any random distribution of the gaps between the fuel assemblies is simulated, using the MEX code, on the basis of precise calculations (MCU code) and design calculations (BIPR-7 and PERMAK codes). The Monte Carlo method (Zazor code) was used to model the nominal density distribution of gaps in the core for different degrees of curvature of the fuel assemblies. It is shown that the power gain, obtained for the fuel elements by the probabilistic-statistical method, due to the curvature of the fuel assemblies is smaller and makes it possible to substantiate core safety with large perturbations, in contrast to the deterministic “maximum gaps near the most-energy stressed fuel element” method. 5 figures, 1 table, 3 references. Special Design Office “Gidropress.” Translated from Atomnaya énergiya, Vol. 87, No. 3, pp. 210–213, September, 1999.     

Computational Analysis of the initial stage of the accident at the Chernobyl' atomic power plant

VNIIAÉS. I. V. Kurchatov Institute of Atomic Energy. Institute of Nuclear Physics of the Academy of Sciences of the Ukrainian SSR. Translated from Atomnaya Énergiya, Vol. 71, No. 4, 275–287, October, 1991.     

Updating the design of the feeder components for the ITER magnet system

The ITER superconducting magnet system generates an average heat load of 23 kW at 4 K to the cryoplant, from nuclear and thermal radiation, conduction and electromagnetic heating, and requires current supplies 10–68 kA to 48 individual coils. The helium flow to remove this heat, consisting of supercritical helium at pressures up to 1.0 MPa and temperature between 4.3 and 4.7 K, is distributed to the coils and structures through 30 separate feeder lines. The feeders also contain the electrical supplies to the coil, helium supply pipes and the instrumentation lines, and are integrated with the current lead transitions to room temperature. The components consist of the in-cryostat feeders, the cryostat feedthroughs and the coil terminal boxes (CTBs). This paper discusses the functional requirements on the feeder system and presents the latest design concept and parameters of the feeder components.     

Performance of the Ultraheavy Collector of the Trek experiment

We report on the performance of the trek ultraheavy cosmic ray collector, an array of track-etch detectors which was deployed on the Russian space station Mir. Trek is the first space-based cosmic ray experiment to exploit the unique properties of the track-recording glass BP-1. We describe the systematic analysis of the Trek experiment, with emphasis on the calibration and verification of the Trek detectors, the automated scanning system used to locate and measure cosmic ray tracks, and the sources of dispersion in the measurement of cosmic ray charge. We find that the resolution for measurement of charge of ultraheavy galactic cosmic rays in Mir orbit will be 0.39–0.45e in the absence of strong thermal variations or episodes of significantly elevated temperature. We also will discuss the extremely heavy cosmic ray composition observer (ECCO), a planned second generation BP-1 experiment, which would measure the age of galactic cosmic ray nuclei using the actinides as radioactive clocks.     

Calculation of the parameters of the field of a cylindrical absorbing radiator in the direction of the generator

The problem of determining the parameters of the field of a cylindrical absorbing radiator in the direction of the generator was solved for the case where the detection point lies outside the cylindrical surface of the radiator. A program of integrating the expression obtained numerically was developed. The results of calculations of the position of the dose rate isolines were presented for two radiators with relative heights 1 and 10. The maximum error was determined for the chosen numerical integration parameters relative to the exact solution: this error was found to be no greater than 2% for the interval of relative heights of the radiator 0.01–10. It was shown that the proposed scheme for obtaining the integral expression is much mor accurate than the scheme used previously for calculation of the parameters of the field in a range falling within the height of the radiator, 5 figures, 5 references. Affiliate of the North-West Civil Service Academy. Translated from Atomnaya énergiya, Vol. 88, No. 2, pp. 88–92.