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Abstract: The effect of the metal concentration on the interphase distribution and sorption kinetics of 60Co/Co and 65Zn/Zn was studied in experiments with soil suspensions (at the phase ratio of 1: 10) and wetted soil (60% of the total water capacity). It was shown that the sorption of 60Co (65Zn) by the soil solid phase decreases with an increase in the concentration of the heavy isotope in the system owing to the exchange between the radioactive and stable isotopes of the chemical elements; this increases the mobility and potential availability of the radionuclides to plants by many times. No fixation of 65Zn/Zn by the solid phase was revealed in the experiment with the contamination level exceeding the background content of Zn in the soddy-podzolic soil by two-three times. Upon the application of 100–600 mg of Zn/kg of soil, the concentration of Zn and the volumetric activity of 65Zn in the soil solution decreased by two times in 12–9 and 15–8 days, respectively.

Abstract: The effect of Co and Zn on the accumulation of 60Co and 65Zn by plants was studied in experiments with growing barley on a soddy-podzolic soil and a chernozem containing the radionuclide and increasing concentrations (from the background level to a high degree of contamination) of the corresponding metal. The root uptake of 60Co was directly related to the soil contamination with Co and its accumulation in the plants, while an inverse relationship was observed between the activity of 65Zn in the plants and the content of Zn in the soil. It was concluded that the transfer of the radionuclide into the plants under mixed radioactive and chemical contamination depended, on the one hand, on the mobile reserve of the stable nuclide in the soil and the solid phase potential to release its ions into the soil solution and, on the other hand, on the requirement of the plants for this element and the uptake rate of its ions by the roots from the solution.

Abstract: The adsorption and ion-exchange behavior of Co, Cu, Zn, and Cd were studied in two soils of different genesis. The sorption parameters and selectivity coefficients of the Me-Ca ion exchange were determined using the Langmuir and Freundlich adsorption isotherms and two models of ion-exchange sorption based on the mass action law (a polyfunctional ion exchanger and a mixture of two ideal exchangers) for describing the relationships between the dissolved and sorbed metal forms. It was shown that simple models provided information for better understanding of the behavior of metals in sorption and ion-exchange processes, but the conclusions about the sorption of different metals in a specific soil or a specific metal in different soils based on these models can be different.

Soil contamination with Co and Cd at concentration 20–25 times exceeding the Maximum Permisible Level for sod-podzolic light loam soil produced not only negative effects on the spring barley productivity formation, but also decreasing of 137Cs root uptake. Effects of Co on the barley development and 137Cs accumulation in plants was more pronounced than Cd influence. The 137Cs activity decrease in barley biomass and harvest amounted to 2.5 and 1.6 times on Cd and Co contaminated soil, respectively. The mechanisms regulating root uptake of K by barley plants in dependence of the kind of soil contamination were discussed. Seed incrustation with Zircon and Epin did not produce significant influence on Co and Cd phytotoxicity, however the use of this plant growth regulators resulted in different in direction and value effects on Co, Cd and 137Cs accumulation in barley plants at various stages of its development. The experimental data do not make it possible to link directly the effect of biologically active substances on 137Cs uptake with their influence on heavy metals toxicity, which was estimated on the base of morphological and physiological parameters of plants.

Abstract: The dynamics of the cationic composition in the liquid phase of a soddy-podzolic soil contaminated with Co and Cd under different pH (changed by addition of H+ ions) was studied in a long-term experiment (for 470 days). Soil solutions were extracted with vacuum samplers installed in the soil for the time of the experiment. It was shown that the concentrations of Co and Cd, as well as those of K, Na, Ca, and Mg, in the solution changed during 3–4 weeks after moistening the air-dry soil to 70% of the maximum water capacity and increased during 5–6 months after addition of H+. This indicated the low rate of the processes and reactions occurring in the soil. The addition of Co and Cd to the soil affected the interphase distributions of K, Ca, and Mg; the effect of Co was higher than that of Cd by 3–4 times. When added together, the Co increased the concentration of Cd in the soil solution by 4–6 times, and the effect of Cd on the content of Co was no higher than 1.5 times.

Abstract: The selective sorption of cesium by some soils, minerals, and natural mineral sorbents was studied using new methodological and experimental approaches. It was found that the total capacity of two types of highly selective sorption sites significantly differing (by several orders of magnitude) in the selectivity coefficients of Cs-K ion exchange makes up 0.5–6% of the total capacity of the ion exchanger. The values of the radiocesium interception potential were determined for the studied soils and minerals.

Abstract Transauricular electroacupuncture prevented stress-induced increase in the degree of anxiety and suppression of exploratory activity in rats. This procedure significantly accelerated decision-making process during acute stress in both control and prestressed rats. Transauricular electroacupuncture decreased the number and area of erosions by producing a pronounced antistress effect at the central and peripheral levels.

We showed that stress response and apoptosis in macrophages depend on the phenotype of their secretory activity and specific biological and physical characteristics of the factor inducing stress-response or apoptosis.

Abstract: We showed that stress response and apoptosis in macrophages depend on the phenotype of their secretory activity and specific biological and physical characteristics of the factor inducing stress-response or apoptosis.

The convergence properties of the mismatch in identification in a closed-loop control system are used to formulate additional simplified adaptability conditions for improving the well-known conditions for control systems with an identifier and reference model. These conditions admit considerable variations for the estimates of the control effectiveness matrix in the neighborhood of their exact values, thereby corroborating the possibility of using the adaptation scheme for a wide class of objects. An illustrative example is given.

A pseudospark gap is described that is capable of interrupting a current of up to 1 kA and shaping voltage pulses with an amplitude of up to 110 kV and rise time of ∼100 ns. Analytical expressions for calculating the energy released in the device at the switching-off stage and the efficiency of the generator with an inductive energy storage system are obtained. The characteristics of the pseudospark gap and of a similar-design thyratron connected in the same circuit are compared. It is found that the turn-off time of the pseudospark gap is shorter than that of the thyratron by a factor of 2.5.

We demonstrated selective activation of caspases in the thymus during heat shock, i.e. primary activation of initiator caspase 9 (but not caspase 8) and effector caspase 3 (but not caspase 6). Preadaptation to heat improved animal survival after heat shock and reduced heat shock-induced activation of both initiator and effector caspases. Hence, adaptation to heat produced an antiapoptotic effect, which was not selective towards receptor-dependent or mitochondrial pathway of the caspase cascade activation.

Tensor, matrix, and quaternion formulations of Dirac–Kähler equation for massive and massless fields are considered. The equation matrices obtained are simple linear combinations of matrix elements in the 16-dimensional space. The projection matrix-dyads defining all the 16 independent equation solutions are found. A method of computing the traces of 16-dimensional Petiau–Duffin–Kemmer matrix product is considered. We show that the symmetry group of the Dirac–Kähler tensor fields for charged particles is SO(4, 2). The conservation currents corresponding this symmetry are constructed. We analyze transformations of the Lorentz group and quaternion fields. Supersymmetry of the Dirac–Kähler fields with tensor and spinor parameters is investigated. We show the possibility of constructing a gauge model of interacting Dirac–Kähler fields where the gauge group is the noncompact group under consideration.

A high-voltage pulse generator with an inductive energy storage is described. Its operation is based on the current interruption by a thyratron. It was shown that a TГИ2-500/20 thyratron is capable of reliably interrupting the current with an amplitude of 800–850 A in an inductive energy storage, forming from a low-voltage (0.5–2 kV) power source voltage pulses with an amplitude of up to 90 kV and leading edge duration of 200–250 ns at the load.

We investigate the theory of particles with arbitrary spin and magnetic moment in the Lorentz representation (0, s) ⊕ (s, 0) in an external constant and uniform electromagnetic field. We obtain the density matrix of free particles in pure spin states. The differential probability of pair producing particles with arbitrary spin by an external constant and uniform electromagnetic field is found using the exact solutions. We calculate the imaginary and real parts of the Lagrangian in an electromagnetic field that takes into account the vacuum polarization.

Within the framework of a multi-year program of dense interstellar gas studies, we performed a new series of observations at the CrAO RT-22 radiotelescope in July 1998 using an improved 3-mm wavelength receiving facility. An acousto-optical spectrum analyzer (AOS) was used for the first time for the spectral analysis of incoming radiation. The AOS has larger bandwidth compared to the filter spectrum analyzer used previously and simplifies tuning SIS-mixer circuits and frequency converters. Using this facility, we observed a number of star-forming regions including clouds associated with bright IR sources and ultracompact HII regions as well as clouds with high-velocity outflows in the HCO+, 13CO, HCN, and CS molecule lines.

The scientists in the Department of Oil and Gas Processing Equipment have been actively involved in the development, investigation, and industrial introduction of contact equipment for mass-transfer reactors for more than 40 years. The first studies in this area were conducted at the beginning of the 1950s by I. A. Aleksandrov and Yu. K. Molokanov under the direction of Professor A. I. Skoblo.

A new concept for large size, complex geometry high field superconducting (SC) magnets has been proposed. According to the approach, a coil is comprised of plane helical turns with insulating layers between them. In this paper, the term “superconducting plane-turns helical magnet” or “helicoid” is often substituted by “plane-turns magnet” or “plane-turns coil” in order to avoid possible interpretation as the well-known fusion magnetic confinement scheme “helical devices.” The following advantages of these magnets over traditional ones are outlined for fusion applications: high bending stiffness, optimal current distribution, favorable high current design, and the possible utilization of brittle materials such as ceramics (HTc superconductors, insulators of high radiation tolerance). Some limitations resulting from hysteresis losses restrict the range of application by stationary mode magnetic systems. It is shown that these limitations aren't so severe for toroidal coils and that poloidal fields slightly affect operating characteristics, thus the design seems to be attractable for tokamaks. Brief theoretical and experimental foundation as well as some consideration on conceptual plane-turns SC coil for fusion are presented.

A muon spin relaxation rate in a super-pure sample of bismuth has been measured. The experimental data and the theory of coherent diffusion in crystalline lattices with shifted levels are compared.

AμSR study has been carried out on high resistivity single crystal gallium arsenide (GaAs). Three characteristic states involving theμ+ muon (Mu*, Mu,μ+ were shown to exist in a binary semiconductor, similar to the case of elemental semiconductors.

Radiation defects are shown experimentally to affect differently the normal and anomalous muonium states in silicon. This evidences essentially different mobilities of the two muonium states in the sample lattice.

The muon spin relaxation rateΛ (T) in an orientated polycrystalline sample of erbium constructed of large monocrystals has been measured for temperatures 20 N, whereTN=84.4 K is the Néel temperature. This fact may be explained by assuming that atT=TN erbium undergoes a weak phase-transition of the first order.

A four-fermion interaction which includes right singlets of both up and down fermions is included in the initial locally SU(2)⊗S(1)-invariant model. In the suitable approximation, the propagators are constructed and the mass spectrum is found of fermi and gauge vector fields as well as of the collective scalar fields due to the dynamical symmetry breakdown.

We consider a P-odd variant of a spin-3/2 particle theory in the matrix formulation. We determine a matrix algebra of a first-order equation. We find solutions of the free equation for a massive particle in the form of projection matrices-dyads. We obtain exact solutions of the equation in the case of an external plane wave field with linear polarization and in the case of an axially symmetric magnetic field.

We study dynamical symmetry breaking and mass generation in a U(5) four-fermion model with two coupling constants. We show that the consistency conditions result in a connection between the dynamical masses of the fermion quintuplet. The masses of fermions and of collective states are expressed through two independent quantities only. We find the propagator of the collective fields, from which it follows that there are goldstone fields as well as fields of massive particles. The mass formulas are obtained on the basis of dimensional regularization of divergent integrals.

Instanton-induced four-quark interactions of u and d-quarks is studied. It is shown that there is a possibility of scalar and pseudoscalar condensates formation, leading to a spontaneous breakdown of the CP-parity. Using self-consistency conditions, relationships are found between current masses of the quarks and their dynamical masses and parameters reflecting the degree of CP-violation. The mass matrix of scalar and pseudoscalar mesons, which are bound states of quarks, is computed.

The model of a scalar structured particle is considered, which possesses polarizability in an external electromagnetic field. The expression for the 4-dimensional current density is found. The exact solution of the equations describing a scalar particle with polarizability in a uniform external magnetic field is obtained. Up to the terms of order O(H2), the energy spectrum can be formally obtained by the substitution of the particle mass in the expression for a pointlike scalar particle: m?m-?H2/2, where? is the magnetic polarizability of the particle. It is shown that the rms radius of a trajectory can be obtained by the substitution of the charge in the well-known formula for a structureless scalar particle: e?e(1{-aH2/m)1/2 (wherea is the electric polarizability).

It is shown that dynamic symmetry breaking in the locally SU(2) ? U(1)-invariant model with mixed inclusion of fermions in a four-fermion interaction leads to a situation in which one collective scalar field, representing the sum of all generations of fermion-antifermion pairs, acts as the total (one-loop) effective Lagrangian. Mass formulas are found for the scalar field and gauge vector fields. The effective Lagrangian obtained coincides in form with the standard Lagrangian in the Glashow-Weinberg-Salam theory of electroweak interactions.

Expressions for the total cross sections of elementary interaction processes between the primary fermion scalar fields and the scalar fields generated by dynamical symmetry breaking are derived within the framework of the globalSU (2)L⊗U (1)-invariant four-fermion model by means of lowest-approximation loop expansions of the propagators for the indicated fields.

Using the Dyson-Schwinger equation, the four-fermion Green functions in one-loop approximation to the SU(2)L ? U(1) four-fermion model are found, as well as corrections to them. An expression is obtained for the collective field propagator in the one-loop approximation, and its regularization is performed. In the model under consideration, collective excitations are identified with a massless Goldstone field and a massive scalar field. It is shown that as a result of the reconstruction of the vacuum, one fermion (the analog of the neutrino) is massless, while the other (the analog of the electron), massive.

Abstract: The results of muon method investigation of the magnetic circuits for electric machines on some technological stages were presented. The influence of various factors on magnetic properties of core elements was shown.

Abstract: Magnetic texture and magnetic inhomogeneity of anisotropic and isotropic electrotechnical steels have been investigated under different conditions of thermomechanical treatment and internal tensions estimated. The μSR-technique has also been used for investigations of magnetic circuits in electrical machines.

Abstract: The zero field μSR-method has been used to study the magnetism in the disordered magnetic alloy Fe82−xNixCr18 near the three-critical, pointx=25. The dynamic and static local field distributions are analyzed. The difference between spin-glass states obtained either from the paramagnetic or after the double transition is discussed.

Abstract: The results of an experimental investigation of the quadrupole interaction of muonium atom in-quartz in the temperature region 75–300 K are presented. It is show that the observed temperature dependence of the quadrupole interaction parameters is fully determined by the diffusion of muonium.

A phase shift analysis ofpN scattering has been carried out at 18 discrete energies in the region 160–600 MeV. Charge splitting of theP33 phase shift (~-2 degree) is observed with a change of sign at ~-350 MeV and vanishing at ~-600 MeV. Marked deviations from an earlier analysis are found forS andP-amplitudes as a result of using new precision data and an untraditional method of the analysis.

Exact solutions are obtained for the wave equations for a scalar particle that possesses polarizability in the field of a plane electromagnetic wave of arbitrary polarization and in a constant electric field.

This paper presents the results of an experiment in which the polarization parameterP in p+p elastic scattering has been measured in the energy range from 335 to 580 MeV. The experiment was performed on a pion channel of the LNPI synchrocyclotron using a polarized proton target and wire spark chambers with magnetostrictive read-out. The results have substantially higher precision in comparison with the most of other experiments in this energy range and allow to determine unambiguously the shape of angular dependenceP(?*) in the whole investigated region. New phase-shift analysis of p+p scattering data has been performed. The results of this experiment were used also to check isospin invariance.

A simple method for limiting the losses of liquid helium and the pressure rise in a cryostat in transitions of superconducting magnets to the normal state is suggested. It involves the application of a layer of porous fiber insulation to the magnet surface. We investigated the influence of such a layer on the amount of liquid helium evaporated and on the pressure rise in a cryostat in the transition of a superconducting laboratory-scale magnet to the normal state.