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Two azo dyes 2-hydroxy-5-(4-nitrophenylazo)benzaldehyde and 2-hydroxy-5-(4-chlorophenylazo)benzaldehyde dissolved in carbon tetrachloride, hexane, acetone and acetonitrile were irradiated with 365 nm UV light, and processes, occurring in them, were studied by NMR and UV–vis spectroscopy. It was established that reversible trans/cis photoisomerization of the molecules occurs in the non-polar solvents and is not observed in the polar solvents. 2D NOESY NMR spectroscopy was used to identify isomers of the azo compounds. Based on the chemical shifts of the signals, it was established that these compounds are in the trans-form before UV irradiation. Spectra of the azo dyes before and after UV irradiation allowed assignment of the chemical shifts of the cis-isomers. In polar solvents these compounds undergo a hypochromic effect under heating or irradiation with UV light. Both compounds exhibit solvatochromism. The shifts in NMR signals caused by photoisomerization of the molecules were compared with the shifts in the NMR signals of other azo compounds such as Disperse Orange 3, Disperse Red 1 and azobenzene. [ABSTRACT FROM AUTHOR]

The work is devoted to modeling the heating of moving active elements from CdSe and estimates emerging optical inhomogeneities. Active elements in the form of a parallelepiped are considered, which rotated in a circle perpendicular to the generation axis. As a result of calculations, it was found that the temperature distribution in the active element that occurs during the operation of the laser can be represented as the sum of two components. The first component is formed due to the balance between heat emission in the active element due to pumping and heat removal from it, which leads to the appearance of an aberration, which is the sum of "tilt" and "defocusing". The second component is formed directly during the passage of the pump spot through the active element, is determined only by the heat release density and is not related to the cooling method of the active element. It leads to the appearance of "Gaussian" aberration, the amplitude of this aberration is directly proportional to the power of heat emission and inversely proportional to the frequency of rotation of the active element. [ABSTRACT FROM AUTHOR]

The decay widths of ρ ′ → π π , ω π , ρ η , ω ′ → ρ π , ω η and π ′ → ρ π are recalculated within the extended Nambu–Jona-Lasinio (NJL) quark model. It is shown that the mass of ρ ′ (1 4 5 0) meson derived in the NJL model agrees with the one given in Particle Data Group tables but significantly deviates from the recent result of CMD-3 collaboration. Comparisons with earlier theoretical results are presented. [ABSTRACT FROM AUTHOR]

The structure and superconducting properties of the Fe1 –x(A)x(Se0.2Te0.8)0.82 (x = 0.1, 0.2) compound, where A is Cu, Zn, Bi or Group IV elements (Pb, Sn, Ge), were studied. It was shown that the effect of substitution of some iron atoms on the structure and superconducting properties of the Fe(Se,Te) compound depends on whether a solid solution with a substituting element was formed. If complete dissolution of the replacement element occured (Cu, Zn), then a significant degradation of the superconducting properties was observed. If a separate chalcogenide phase was formed (substitution by Pb, Sn, Ge), then a slight change in the superconducting properties was observed. Such a slight change and even improvement in the superconducting properties upon precipitation of the chalcogenide phase can be associated with both the positive effect of an increase in the relative content of iron and a decrease in the number of iron atoms in the interstitial sites of the β-phase. The preservation of the superconducting properties of the Fe(Se,Te) compound with a small substitution of iron for group IV elements can be used to create wires based on Fe(Se,Te), since impurity chalcogenide particles can act as effective pinning centers. [ABSTRACT FROM AUTHOR]

In order to study the effect of the chemical structure of the equatorial ligand on the spin state of the Fe(iii) ion in complexes with invariable photoisomerizable 4-styrylpyridine axial ligands and different tetradentate Schiff bases, several new Fe(iii) complexes have been first synthesized, characterized, and studied by UV-vis, NMR, and EPR spectroscopies. The general chemical formula of the complexes is [Fe(SB)Sp2]BPh4·MeOH, where Sp is trans-4-styrylpyridine and SB are dianions of Schiff bases: salen, bzacen, and acen [salen = N,N′-ethylenebis(salicylaldimine) 1, acen = N,N′-ethylenebis(acetylacetonylideneimine) 2, and H2bzacen = N,N′-ethylenebis(benzoylacetonylideneimine) 3]. The results of the EPR and NMR measurements of the complexes both in the solid state and in solutions showed that the more methyl groups and less aromatic rings in the equatorial ligand, the more abrupt spin-crossover was observed in the complex. The dependence of the magnetic properties of the complexes on the state of matter and the presence of a solvent (powder, liquid solutions, and vitrified solutions) are noted. [ABSTRACT FROM AUTHOR]

In this work, we study the magnetization of two types of particles of a composite consisting of polystyrene and multilayer graphene chemically bonded to it, obtained by magnetic separation of the initial composite. For needleshaped particles, a ferromagnetic type of magnetization was observed for the first time, with values of saturation magnetization that are large for graphene. For flat, macroscopic particles of the composite, a superposition of several contributions to the magnetization was observed. [ABSTRACT FROM AUTHOR]

The widths of the decays τ → K - K + K - ν τ and τ → K - K 0 K ¯ 0 ν τ are calculated in the U (3) × U (3) chiral quark NJL model. Four channels are considered: contact, axial vector, vector, and pseudoscalar channels. It is shown that the dominant contribution is given by the axial vector channel with an intermediate ϕ meson. The results obtained are in satisfactory agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The branching fractions of τ lepton decays with the production of strange scalar mesons both in the ground and first radially excited states and are calculated in the extended chiral quark Nambu–Jona-Lasinio model. All mesons are considered as systems. The obtained results should be considered as predictions for future experiments. [ABSTRACT FROM AUTHOR]

Reflection spectra of quasi-two-dimensional organic conductors (EDT–TTF)4[Hg3I8]1–x, are considered, which, depending on the composition, demonstrate different phase transitions: x = 0.027—metal–superconductor with Tc = 8.1 K, x = 0—metal–insulator at a temperature of T < 35 K. The polarized reflection spectra were analyzed using the "phase phonons" model, which takes into account the electronic-vibrational interaction. Using this model, the optical functions of both compounds were adequately described and the energy parameters of the π-electron system were obtained. It is shown that for the compound with x = 0.027 these parameters change monotonically with temperature, while for x = 0 they show a jump at the phase transition temperature. A comparison of the model parameter Δ (the value of the periodic potential) for crystals with different stoichiometric coefficients x = 0 and 0.027 was carried out and an assumption was made about the dependence of the periodic potential on the average charge of one EDT molecule. [ABSTRACT FROM AUTHOR]

The branching fractions of the decays η ′ → π ρ and ρ → π η are calculated in the chiral quark NJL model. The decays exist due to the mass difference between u - and d -quarks leading to π 0 − η ′ and π 0 − η mixing. Two different approaches are applied: the approximate calculation of this process, taking into account the transitions π 0 − η ′ and π 0 − η explicitly without diagonalization and a more precise approach consisting in the diagonalization of the singlet and octet states leading to the physical fields π 0 , η and η ′ . The obtained results are in satisfactory agreement with current experimental data. [ABSTRACT FROM AUTHOR]

The total cross sections for the e+e– → a1π, e+e– → K1(1270)K, and e+e– → K1(1400)K processes have been calculated within the U(3) × U(3) chiral Nambu–Jona-Lasinio model. Since experimental data on these processes are absent, the reported theoretical results can be treated as predictions. [ABSTRACT FROM AUTHOR]

We approach the task of computing a carefully synchronizing word of minimum length for a given partial deterministic automaton, encoding the problem as an instance of SAT and invoking a SAT solver. Our experiments demonstrate that this approach gives satisfactory results for automata with up to 100 states even if very modest computational resources are used. We compare our results with the ones obtained by the first author for exact synchronization, which is another version of synchronization studied in the literature, and draw some theoretical conclusions. [ABSTRACT FROM AUTHOR]

The dependence of magnetization M on magnetic field H was measured for a thin superconducting niobium plate with strong magnetic flux pinning with the field oriented normally and parallel to the sample plane. At T < Tc, dependences M(H) show a hysteretic behavior with a peak effect in large fields; the shape of the hysteresis loop depends on the field orientation. At temperatures below ~Tc/2 magnetic field jumps appear on dependences M(H), and their behavior also depends on the field orientation. When a good conductor is in the in a good thermal contact with the planar superconducting sample, the flux jumps are noticeably reduced in the perpendicular field orientation, while the flux jumps in the parallel orientation remain unchanged. The decrease in the magnitude of the flux jumps with a transverse orientation of the magnetic field occurs due to the electrodynamic braking of magnetic instability, which could lead to a magnetic flux jump. [ABSTRACT FROM AUTHOR]

The dependence of magnetization M on magnetic field H was measured for a thin superconducting niobium plate with strong magnetic flux pinning with the field oriented normally and parallel to the sample plane. At T < Tc, dependences M(H) show a hysteretic behavior with a peak effect in large fields; the shape of the hysteresis loop depends on the field orientation. At temperatures below ~Tc/2 magnetic field jumps appear on dependences M(H), and their behavior also depends on the field orientation. When a good conductor is in the in a good thermal contact with the planar superconducting sample, the flux jumps are noticeably reduced in the perpendicular field orientation, while the flux jumps in the parallel orientation remain unchanged. The decrease in the magnitude of the flux jumps with a transverse orientation of the magnetic field occurs due to the electrodynamic braking of magnetic instability, which could lead to a magnetic flux jump. [ABSTRACT FROM AUTHOR]

The effect of the interaction of mesons in the final state is additionally considered within the description of τ → π η (η ′) ν τ decays. This interaction is taken into account at the level of production of intermediate pions. One of them, in turn, might be transited into η or η ′ mesons. Our results do not exceed the experimentally established branching fractions, and they are in agreement with the results of other theoretical studies. [ABSTRACT FROM AUTHOR]

The partial width of the decay has been calculated within the extended Nambu–Jona-Lasinio model including the contact and vector channels. The contributions from the ρ meson in the ground and first radially excited states have been taken into account in the vector channel. The results are in satisfactory agreement with experimental data. The inclusion of the final-state interaction of kaons results only in insignificant corrections within the accuracy of the model. [ABSTRACT FROM AUTHOR]

The width of the decay has been calculated within the extended Nambu–Jona-Lasinio model including the final-state interaction of mesons. Both the contact term and the channel with the intermediate ground state and its first radial excitation have been taken into account. To describe the final-state interaction, a triangle diagram with three mesons has been considered. The cutoff parameter in the diverging integrals over the meson loop has been taken the same as in our preceding work to describe the decay, so no additional parameters are introduced. Satisfactory agreement with experimental data has been obtained. [ABSTRACT FROM AUTHOR]

The feasibility of underwater acoustic communications in an ice-covered shallow-water area is demonstrated in a field experiment and by computer modeling. The advantages of vertical linear receiver arrays with different lengths and different numbers of hydrophones are investigated. The study analyzes the case when the water area depth is much smaller than the distance to the receiver array. A comparative analysis of several algorithms of spatial signal processing for binary phase-shift keyed signals with a carrier frequency of about 1 kHz at different information transmission rates is carried out. The experiment was conducted on Lake Baikal with an ice cover thickness ≈66 cm and under intense acoustic noise associated with crack formation in the ice surface. It is shown that when a vertical array is used, the bit error rate can be reduced by more than three times versus a single receiver. [ABSTRACT FROM AUTHOR]

The decay has been described within the Nambu–Jona-Lasinio model including the contact term and the contribution from an intermediate vector meson. The final-state interaction of mesons has been taken into account by the inclusion of diverging meson loops. The additional ultraviolet cutoff parameter in these loops is fixed using the experimental width of the process under consideration. [ABSTRACT FROM AUTHOR]

The results of experimental studies of underwater acoustic communication at frequencies of 500–1000 Hz using vertical chains of hydrophones (linear arrays) are presented. The experiments were carried out in the coastal area of Lake Baikal covered with continuous ice. It is demonstrated that the use of vertical arrays in shallow water areas with ice cover can effectively suppress natural background noise when such receiving modules cover the entire water layer over depth. This allows to reduce by an order of magnitude the bit error rate in comparison with reception by a single hydrophone. [ABSTRACT FROM AUTHOR]

The τ− → π−π0ντ and e+e− → π+π− processes have been described within the chiral Nambu—Jona-Lasinio model including the interaction of pions in the final state beyond the 1/Nc approximation. A loop correction caused by the ρ-meson exchange between pions, which makes the leading contribution in the P-wave channel, is taken into account. The results are in satisfactory agreement with experimental data for both processes. [ABSTRACT FROM AUTHOR]

The magnetization process in the nanocomposite BiFeO3–Bi2Fe4O9 obtained by the glycine–nitrate combustion, was studied. The magnetic characteristics of the individual compounds BiFeO3 and Bi2Fe4O9 and of the composite were found to be substantially different. The new properties of the synthesized substance are ascribed to the exchange interaction on the interface between the phases. [ABSTRACT FROM AUTHOR]

In this work, the mixing angle of the vector ω (7 8 2) and ϕ (1 0 2 0) mesons is estimated in the framework of Nambu–Jona-Lasinio model. The decay ϕ → π 0 γ is considered as a basic process to determine this angle. The obtained value is compared with the results of the other authors. Besides, the width of the decay ϕ → 3 π and the cross-section of the process e + e − → π 0 ϕ are calculated by using this angle. [ABSTRACT FROM AUTHOR]

In the extended Nambu–Jona-Lasinio model, the branching fraction of τ → K ∗ 0 (8 9 2) K − ν τ is calculated. The contributions from the contact diagram and the diagrams with intermediate axial-vector, vector and pseudoscalar mesons in the ground and first radially excited states are taken into account. It is shown that an axial-vector and vector channel with a contact diagram give a dominant contribution to the branching fraction. The obtained results for the branching fraction τ → K ∗ 0 (8 9 2) K − ν τ are in satisfactory agreement with experimental data. A prediction for the differential distribution over the invariant mass of the meson pair K ∗ 0 (8 9 2) K − is given. [ABSTRACT FROM AUTHOR]

We have studied the magnetic properties of a nanocomposite obtained by the introduction of magnetite particles from a colloidal solution in kerosene into channels of porous silicon. Temperature dependences of the parameters of samples were measured, and their specific features were established. It is suggested that the obtained magnetic material consists of two fractions, one of which exhibits superparamagnetic behavior and the other of which occurs in the blocked state up to room temperature. [ABSTRACT FROM AUTHOR]

In the extended Nambu–Jona-Lasinio (NJL) model, the decay widths of τ → (K , K (1 4 6 0)) ν τ , (K , K (1 4 6 0)) → μ ν μ are calculated. The contributions from intermediate axial-vector mesons K 1 (1 2 7 0) , K 1 (1 4 0 0) and the first radially excited state K 1 (1 6 5 0) are taken into account. Estimates for the weak decay constants F K and F K ′ are given. Predictions are made for the width of τ → K (1 4 6 0) ν τ decay and F K ′ constant. [ABSTRACT FROM AUTHOR]

The width of the τ → K ¯ 0 * (892) π − ν τ decay has been calculated within the extended Nambu-Jona-Lasinio model taking into account intermediate axial-vector, vector, and pseudoscalar mesons in the ground and first radially excited states. The splitting of the axial-vector intermediate state K1A into two physical mesons K1(1270) and K1(1400) caused by the mixing of axial-vector strange mesons from the 3P1 and 1P1 nonets has also been taken into account. The results are in satisfactory agreement with experimental data. [ABSTRACT FROM AUTHOR]

Numerical simulation is applied to analyze the possibilities of using vertical receiving arrays covering the entire waveguide for underwater acoustic communication on the shallow Arctic shelf. Binary phase shift keying with a carrier frequency of 750 Hz is selected for data transfer. It is shown that an algorithm for selecting acoustic signals corresponding to the first waveguide mode or an algorithm based on using passive-phase conjugation eliminates intersymbol interference. In case of spatial signal processing and waveguide depth of 30 m the error-free information transmission is possible when the signal-to-noise ratio is ≈15 dB less than that for a single receiver. It has been demonstrated these advantages to be present in different conditions on the Arctic shelf: with an acoustically soft or acoustically hard bottom, with surface waves, or with ice cover. [ABSTRACT FROM AUTHOR]

In the paper the test data on new cycle-resistant thermoelectric modules are presented and discussed. These modules can be applied in medical equipment for polymerase chain reaction (PCR) to carry out DNA analysis with the help of rapid periodic heating and cooling of biological probes. However, high density of heat fluxes and, as a result, significant mechanical stresses in miniature thermoelectric modules involve special requirements to their reliability. The company RMT Ltd. has developed a technology for the production of highly reliable miniature thermoelectric modules that allowed them to withstand more than 500 thousand heating-cooling cycles (from 20 to 100°C) with a rate of 20°C/s and more. [ABSTRACT FROM AUTHOR]

High-power solid state lasers of the mid-IR spectral range are extremely interesting for both basic research and technological applications and they are actively developing at present. However, the implementation of projects with the use of such lasers is hampered by the absence of Faraday isolators (FIs) for the radiation with the corresponding characteristics. The need for such devices is growing with laser power enhancement. They reduce the risk of self-excitation of the damage of amplifiers and optical elements and are a handy tool for organizing multipass schemes. Magneto-active crystals based on Eu2+ ions are promising media for the development of FIs for high-power lasers of the mid-IR spectral range because of the unique combination of their spectral and magneto-optical properties. Thermo-optical characteristics are also of principal importance when operating with high-power laser radiation. This letter presents the results of investigation of thermo-optical constants Q and P of the EuF2.11 solid solution crystal which determines the values of polarization and phase distortions of passing laser radiation. The measured values can be considered as the corresponding values for the EuF2 crystal, which is of greatest interest for the development of FIs for high-power mid-IR lasers. The obtained results can be used to determine the characteristics of FIs based on EuF2 crystals in various implementations of their optical schemes for various parameters of laser radiation. According to the estimates, for the radiation wavelength of 2 μm, the maximum permissible laser power of the Faraday isolator based on one magneto-optical element with [001] orientation will be more than 200 W. [ABSTRACT FROM AUTHOR]

The widths of the τ → [ρ0(770), ρ0(1450)]π−ντ decays have been calculated within the extended Nambu—Jona-Lasinio model including both the ground and first radially excited intermediate meson states. The axial-vector channel with intermediate a1 mesons dominates. The values of the masses and total widths of the a1 meson recently obtained by the COMPASS and JPAC Collaborations have been taken into account. [ABSTRACT FROM AUTHOR]

There are two major structure theorems for an arbitrary regular semigroup using categories, both due to Nambooripad. The first construction using inductive groupoids departs from the biordered set structure of a given regular semigroup. This approach belongs to the realm of the celebrated Ehresmann-Schein-Nambooripad Theorem and its subsequent generalisations. The second construction is a generalisation of Grillet's work on cross-connected partially ordered sets, arising from the principal ideals of the given semigroup. In this article, we establish a direct equivalence between these two seemingly different constructions. We show how the cross-connection representation of a regular semigroup may be constructed directly from the inductive groupoid of the semigroup, and vice versa. [ABSTRACT FROM AUTHOR]

The kinetics of cathodic reactions in ammonium acetate solutions proposed for electrodeposition of metallic molybdenum was studied. The reduction of molybdenum compounds in the oxidation state +6 was found to occur stepwise according to the scheme Mo(VI) → Mo(V) → Mo(III). The waves observed on the polarograms are complicated by adsorption effects. The reduction of molybdenum to the metallic state is possible only at high negative potentials of the cathode; under the polarographic analysis conditions, this wave was not recorded. The deposit that formed on the surface of the solid cathode during cathodic polarization (i = 0.5 A cm-2) contains both molybdenum in the metallic state and molybdenum oxides. The ratio between the electrolysis products depends on the temperature of solution: a decrease in the temperature leads to an increase in the amount of metallic molybdenum. [ABSTRACT FROM AUTHOR]

Abstract: Model experiments are used to obtain the transfer functions of an Arctic-type shallow-water acoustic waveguide in the spring-summer period, including in the presence of surface waves. The calculations were performed for frequencies from 150 to 1000 Hz using the theory of coupling modes. From the numerical simulation results, the usable frequency range is determined for stable underwater communications suitable for waveguides with both acoustically soft and acoustically hard bottoms. It is demonstrated that for certain distances between the sound source and receiver and their location depths, errorless information transmission can be achieved even without special processing methods. Channel compensation with passive time reversal leads to increased transmission reliability predominantly in a waveguide with an acoustically hard bottom. [ABSTRACT FROM AUTHOR]

The width of the τ→K¯*0(892)π−ντ decay is calculated within the Nambu-Jona-Lasinio model taking into account four channels of the formation of the τ→K¯*0(892)π− pair—the contact interaction and three channels with intermediate axial-vector, vector, and pseudoscalar mesons. Leading contributions arise from the contact interaction and axial-vector channel with an intermediate ground-state K1(1270) meson. Our theoretical estimate adequately reproduces the measured τ→K¯*0(892)π−ντ decay width. [ABSTRACT FROM AUTHOR]

In an earlier paper, the second-named author has described the identities holding in the so-called Catalan monoids. Here we extend this description to a certain family of Hecke-Kiselman monoids including the Kiselman monoids Kn. As a consequence, we conclude that the identities of Kn are nonfinitely based for every n ≤ 4 and exhibit a finite identity basis for the identities of each of the monoids K2 and K3. [ABSTRACT FROM AUTHOR]

The production of ρ(770)η meson pairs in electron–positron collisions and in the decays ρ(1450) → ρ(770)η and τ → ρ(770)ηντ is calculated in the framework of the extended Nambu–Jona-Lasinio model. The contributions with intermediate ρ mesons in both the ground and first radially excited states are taken into account when calculating processes associated with electron–positron annihilation and decay of the tau lepton. The width of the decay τ → ρ(770)ηντ is theoretically estimated. The results obtained for other processes are consistent with the existing experimental data. [ABSTRACT FROM AUTHOR]

We exhibit an example of a finitely presented semigroup S with a minimum number of relations such that the identities of S have a finite basis while the monoid obtained by adjoining 1 to S admits no finite basis for its identities. Our example is the free product of two trivial semigroups. [ABSTRACT FROM AUTHOR]

The processes in the threshold domain are considered in the framework of the extended Nambu-Jona-Lasinio model. The channels with the ground , and radially excited , intermediate meson states are taken into account. It is shown that in the process , the probability of the subprocesses with -mesons significantly exceeds the probability of the subprocesses with -mesons, whereas, in the process , - and -channels give approximately equal contributions. The mechanism of this effect is discussed. The radiative decay widths of , , and are calculated. [ABSTRACT FROM AUTHOR]

In the framework of the Nambu-Jona-Lasinio (NJL) model, a mechanism for eliminating the off-diagonal π a transitions from the effective meson Lagrangian is investigated. The problem is considered in the oneloop approximation for the quark loops. We employ the minimal superposition linear in the fields, a= a − c∂π, and show that the covariant transformation properties of both the axial-vector and vector physical fields are affected by this substitution. Contrary to some claims found in the literature, we demonstrate that the discussed change in covariant transformation properties of these fields does not result in various violations of chiral symmetry, but rather reduces to a redefinition of the S-matrix elements beyond the mass shell. At the same time, the covariant and noncovariant approaches yield identical on-shell results. [ABSTRACT FROM AUTHOR]

The well-known [ρ(770), ω(782)] → γ[π, η] electromagnetic decays have been considered within the Nambu-Jona-Lasinio model taking into account contributions from intermediate transitions between axial-vector and pseudoscalar vertices using the [f1(1285), a1(1260)] → γ[ρ(770), ω(782)] vertices recently obtained within this model. The results are in satisfactory agreement with experimental data. [ABSTRACT FROM AUTHOR]

The dependences of the magnetic moment in the graphite-polystyrene composite on the temperature and magnetic field have been studied. It has been shown that the magnetic field dependence of the magnetic moment of graphite particles is characteristic of superconductors in the same temperature interval where a Josephson current-voltage characteristic was previously observed in the same composite. [ABSTRACT FROM AUTHOR]

The processes and are calculated in the framework of the extended Nambu-Jona-Lasinio model. The intermediate vector mesons , , and their first radially excited states are taken into account. The obtained results are in satisfactory agreement with the experimental data. The predictions for the cross-sections of the reactions , and were made. [ABSTRACT FROM AUTHOR]

The full and differential widths of the decay are calculated in the framework of the extended Nambu-Jona-Lasinio model.The contributions of the subprocesses with the intermediate vector mesons (770) and (1450) are taken into account. The obtained results are in satisfactory agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The decays τ → (η, η') K-ν are described in the framework of the extended Nambu-Jona-Lasinio model. Both full and differential widths of these decays are calculated. The vector and scalar channels are considered. In the vector channel, the subprocesses with the intermediate K*(892) and K*(1410) mesons play the main role. In the scalar channel, the subprocesses with the intermediate and K(800) and K(1430) mesons are taken into account. The scalar channel gives an insignificant contribution to the full width of the decay τ → η K-ν. The obtained results are in satisfactory agreement with the experimental data. The prediction for the width of the process τ → η′ K-ν is made. [ABSTRACT FROM AUTHOR]

In this paper, the width of the decay is calculated in the framework of the Nambu-Jona-Lasinio (NJL) model. The contributions of the intermediate vector and scalar mesons are taken into account. It is shown that the main contribution to the width of this decay is given by the subprocesses with the intermediate -boson and vector meson. The scalar channel with the intermediate meson gives an insignificant contribution. In Appendix A, it is shown that the contribution of the subprocess with the intermediate meson is negligible as well. The obtained results are in satisfactory agreement with the experimental data. [ABSTRACT FROM AUTHOR]

In an earlier paper, the second-named author has described the identities holding in the so-called Catalan monoids. Here we extend this description to a certain family of Hecke-Kiselman monoids including the Kiselman monoids Kn. As a consequence, we conclude that the identities of Kn are nonfinitely based for every n ≥4 and exhibit a finite identity basis for the identities of each of the monoids K2 and K3. [ABSTRACT FROM AUTHOR]

Based on kinetic studies, a mechanism for the elution of technetium from an anion-exchanger in the form of an extractable complex with tributyl phosphate (TBP) has been suggested for the purpose of improving the ion exchange technology of the technetium extraction by elution of technetium-99 from VP-1AP anion exchange resin with a TBP solution. The effect of diluents and extraction reagents on the quantitative desorption of pertechnetate has been studied. It has been found that the process of desorption of pertechnetate ions from the VP-1AP anion-exchanger can be described by equations characteristic of the film kinetics of elution, which is caused by the presence of an additional stage of transfer of the substance across the phase interface from the phase of an aqueous solution associated with anion-exchanger to the phase of organic extracting eluent. Based on the conducted studies, the possibility of improving the existing sorption technology of technetium isolation has been demonstrated. [ABSTRACT FROM AUTHOR]