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The main results of solar neutrino experiments are presented, ranging from the pioneering Cl - Ar experiment up to the most recent Borexino data. Solar neutrino fluxes and spectra are given for two versions of the standard solar m...
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The main results of solar neutrino experiments are presented, ranging from the pioneering Cl - Ar experiment up to the most recent Borexino data. Solar neutrino fluxes and spectra are given for two versions of the standard solar model,and radiochemical and electronic detectors are briefly described. The results of ~7Be- and pep-neutrino detection by Borexino are presented. The LMA-MSW oscillation solution of the solar neutrino problem is considered.
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Side self-oxidation of thiols was studied.It was found that those reactions in neutral and alkaline solutions are induced by impurities of variable-valence metals.The ability of transition metals to catalyze oxidation of thiols ch...
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Side self-oxidation of thiols was studied.It was found that those reactions in neutral and alkaline solutions are induced by impurities of variable-valence metals.The ability of transition metals to catalyze oxidation of thiols changes in the order Cu>Mn>Fe>Ni>>Co.The plot of the self-oxidation rate vs.pH passes through a maximum whose position on the pH scale depends on both the nature of metal and the structure of the thiol oxidized.For thiols having different structures,the kinetic orders in reactions catalyzed by copper ions differently very with pH,which is apparently associated with the formation of complexes possessing different catalytic activity.
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Catalysts of oxidation of aminothiols by copper ions was studied depending on the structure of aminothiols and pH of the medium.The catalytic reaction proceeds in the inner coordination sphere of Cu~+.At pH 7-9,oxidation of bident...
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Catalysts of oxidation of aminothiols by copper ions was studied depending on the structure of aminothiols and pH of the medium.The catalytic reaction proceeds in the inner coordination sphere of Cu~+.At pH 7-9,oxidation of bidentate aminothiols involves reduction of O_2 to H_2O_2.At pH 9-13,oxidation of chelating aminothiols is accompanied b reduction of O_2 to H_2O,whereas oxidation of weak-chelating aminothiols still proceeds by the former mechanism.In this process,the thiolate anions coordinate to the Cu~+ ions lose one electron each and are oxidized to amino disulfides,which go from the inner sphere of the Cu~+ complex into a solution.Procedures developed for the determination of amino disulfides,the chemiluminescence determination of H_2O_2 in the presence of aminothiols as luminescence quenchers,and a modified polarographic procedure for the determination of O_2 allowed us to establish that oxidation of aminothiols is not accompanied by catalytic decomposition of H_2O_2 that formed.
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The specific features of the magnetic textures of the multilayer thin film systems [CoFe/TiZr]_(68) and [CoFe/TiZr]~(195) have been studied using polarized neutron reflectometry with an external magnetic field applied in different...
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The specific features of the magnetic textures of the multilayer thin film systems [CoFe/TiZr]_(68) and [CoFe/TiZr]~(195) have been studied using polarized neutron reflectometry with an external magnetic field applied in different ways. A technique has been developed for taking into account systematic errors of the measurement setup, which has made it possible to reveal additional components in specular neutron "spinflip" reflections, whose origin is not related to the well-known mechanism of Zeeman splitting. The samples under investigation are characterized by large differences in hysteresis curves, remanent magnetizations, and magnetic textures. The experimental data have been analyzed using the results obtained by the author in the previous works.
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Neutrophils are the primary cells of the innate immune system. They destroy pathogenic microorganisms carrying out the oxidative stress mechanism through phagocytosis and extracellular traps (NETs). There is no doubt about the nee...
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Neutrophils are the primary cells of the innate immune system. They destroy pathogenic microorganisms carrying out the oxidative stress mechanism through phagocytosis and extracellular traps (NETs). There is no doubt about the need to study neutrophils’ functional activity, but there are some methodological problems with the nativity of conditions in such experiments. The aim of this work is to propose a method of preparing a sample of peripheral blood neutrophils for study by spectral-optical methods (such as confocal microscopy) providing an increased level of the nativity of the conditions.
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The authors of Ref. [1] affirm that the scatter in the results of measurements for many process, represented as a histogram (the frequency of occurrence of a given value versus its magnitude), exhibits 'fine structure' that in add...
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The authors of Ref. [1] affirm that the scatter in the results of measurements for many process, represented as a histogram (the frequency of occurrence of a given value versus its magnitude), exhibits 'fine structure' that in addition oscillates in time with a certain 'cosmophysical' rhythm. Most surprisingly, this phenomenon was observed in the course of measuring the rate of nuclear radioactive decay. So far it has been assumed (and before issuing of Ref. [1] there was no experimental proof to the contrary) that the rate of radioactive decay is described by the Poisson distribution which gives the probability of observing x events in a given time interval with the proviso that the events are independent and occur at a constant rate. When x → ∞ (and practically for x > 10), the Poisson distribution is well approximated by the continuous Gaussian distribution. In principle, the authors of Ref. [1] agree that the rate of radioactive decay obeys the Poisson distribution, but they believe that "the existing goodness-of-fit tests for hypotheses are insensitive to the fine structure of the distributions".
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A common laboratory facility for creating glowing flying plasmoids akin to a natural ball lightning, allowing a number of experiments to be performed to investigate the main properties of ball lightning, is described.
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The atomic structure of single-crystal samples of Fe _1 - _xSi _x (x = 0. 08, 0. 10) alloys has been investigated using X-ray diffraction. It has been shown that the body-centered cubic (BCC) lattice of these alloys contain cluste...
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The atomic structure of single-crystal samples of Fe _1 - _xSi _x (x = 0. 08, 0. 10) alloys has been investigated using X-ray diffraction. It has been shown that the body-centered cubic (BCC) lattice of these alloys contain clusters with local ordering of the B2 type, which are characteristic of alloys with depleted composition (x = 0. 05-0. 06). The Fe _3Si phase with the D0 _3 structure has been revealed at silicon concentrations x = 0. 08 and 0. 10. The volume fraction of Fe 3Si-phase regions increases both with an increase in the silicon concentration in the Fe _1 - _xSi x alloy and during annealing of the samples with this silicon concentration at a temperature of 450°C. Based on the results obtained, it has been concluded that the anisotropic distribution of the B2 clusters, which arises as a result of thermomagnetic or thermomechanical treatment, is responsible for the induction and stability of the uniaxial magnetic anisotropy in the Fe _1 - _xSi _x (x = 0. 05-0. 10) alloys.
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The critical small-angle scattering of polarized neutrons from spin fluctuations in a nickel single crystal with a special inclined geometry of the magnetic field has been studied. The method of inclined geometry makes it possible...
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The critical small-angle scattering of polarized neutrons from spin fluctuations in a nickel single crystal with a special inclined geometry of the magnetic field has been studied. The method of inclined geometry makes it possible to investigate not only two-particle spin correlations but also three-particle spin correlations that determine the polarization-dependent contribution to scattering, which is asymmetric with respect to the momentum transfer q. This contribution depends on the momentum transfer q as 1/(q~2 + ξ~(-2))~(5/2), where f is the neutron scattering correlation length; it linearly increases with an increase in the magnetic field H in the low-field range and then reaches saturation. The results obtained are in good agreement with the similarity theory.
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General principles of polarized-neutron magnetic scattering are presented and their applications are considered. It is shown that this technique is especially useful if the system as a whole contains an axial vector interaction. T...
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General principles of polarized-neutron magnetic scattering are presented and their applications are considered. It is shown that this technique is especially useful if the system as a whole contains an axial vector interaction. The examples of the magnetic field, Dzyaloshinskii-Moriya interaction, and elastic torsion are considered. In all these cases, polarized neutron scattering provides information unavailable with other experimental methods. The theory is illustrated by pertinent experimental results, notably the confirmation of the Polyakov-Kadanoff-Wilson algebra for critical three-spin fluctuations in iron; the first determination of chiral critical exponents in the triangular-lattice antiferromagnets; and the determination of noncollinear magnetic structure for a number of complex antiferromagnets.
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