Variations in the Ozone Concentration in the Stratosphere over Moscow due to Dunamic Processes in the Cold Period of 2015–2016

New data on variations in vertical distribution of stratospheric ozone overMoscow in the cold half-year of 2015–2016 are presented. This period differed significantly from previous winters in a number of stratospheric parameters. The features of these ozone variations are considered and their relation to the stratospheric dynamics is studied. The most significant decrease in the ozone concentration in comparison with average values was observed at the beginning of March, 2016. The development of further significant ozone layer depletion similar to that occurred in spring 2011 was prevented by major sudden stratospheric warming in March 2016.     

Microwave and Lidar Measurements of Ozone and Temperature Variations during Stratospheric Warmings of 2012–2015

Radiophysics and Quantum Electronics - We present the results of joint observations of ozone and temperature in the middle atmosphere above Tomsk in December–January 2012–2013 and in...     

Acoustics of the Great Hall of the Moscow State Conservatory after reconstruction in 2010–2011

The Great Hall of the Moscow State Conservatory was built in the early 20th century. For more than 100 years of service, it had a high acoustic reputation both among musicians and audience. By the beginning of the 21st century, the hall was in nearly critical condition. Thus, major renovation was needed. In terms of architectural acoustics, the main task was to keep the good acoustics of the hall. This paper presents the results of acoustic parameter measurements of the hall after Reconstruction in 2010–2011. The parameters of the hall measured before and after reconstruction are also compared. The comparative acoustic characteristics between the Great Hall and world leading concert halls are given.     

Effect of Variations in the Gas-Dynamic Unloading on the Laser Initiation of the PETN–Aluminum Composite

Technical Physics - Thresholds of explosive decomposition Hcr under irradiation using the first harmonic of a pulsed neodymium laser (14 ns) are experimentally determined for pentaerythritol...     

Estimation of the initial density distribution in plasma–metal liners

We describe a method for estimating the initial density profile of the liner shell from experimental current and voltage oscillograms with correction of the radius of the pinch from its optical images. It is shown that the average radial profile of the initial density distribution of plasma–metal liners can be approximated by two Gaussian curves with different dispersions. The largest contribution to the main peak of the initial density distribution comes from bismuth cathode material (bismuth) ions, while the contribution to the second Gaussian curve is due to the substance of the insulator over the surface of which the vacuum arc is initiated.     

On the Reproduction of the Solar Activity Variations in the Range 2–40 Months in the Interplanetary Medium

Journal of Experimental and Theoretical Physics - We compare the quasi-biennial variations and Rieger-type variations (on a timescale of less than 1 year) in solar activity, interplanetary...     

Evidence for the Gompertz curve in the income distribution of Brazil 1978–2005

This work presents an empirical study of the evolution of the personal income distribution in Brazil. Yearly samples available from 1978 to 2005 were studied and evidence was found that the complementary cumulative distribution of personal income for 99% of the economically less favorable population is well represented by a Gompertz curve of the form G(x) = exp [exp (A-Bx)], where x is the normalized individual income. The complementary cumulative distribution of the remaining 1% richest part of the population is well represented by a Pareto power law distribution P(x) = βx^-α. This result means that similarly to other countries, Brazil’s income distribution is characterized by a well defined two class system. The parameters A, B, α, β were determined by a mixture of boundary conditions, normalization and fitting methods for every year in the time span of this study. Since the Gompertz curve is characteristic of growth models, its presence here suggests that these patterns in income distribution could be a consequence of the growth dynamics of the underlying economic system. In addition, we found out that the percentage share of both the Gompertzian and Paretian components relative to the total income shows an approximate cycling pattern with periods of about 4 years and whose maximum and minimum peaks in each component alternate at about every 2 years. This finding suggests that the growth dynamics of Brazil’s economic system might possibly follow a Goodwin-type class model dynamics based on the application of the Lotka-Volterra equation to economic growth and cycle.     

Modelling study on the three-dimensional neutron depolarisation response of the evolving ferrite particle size distribution during the austenite–ferrite phase transformation in steels

The magnetic configuration of a ferromagnetic system with mono-disperse and poly-disperse distribution of magnetic particles with inter-particle interactions has been computed. The analysis is general in nature and applies to all systems containing magnetically interacting particles in a non-magnetic matrix, but has been applied to steel microstructures, consisting of a paramagnetic austenite phase and a ferromagnetic ferrite phase, as formed during the austenite-to-ferrite phase transformation in low-alloyed steels. The characteristics of the computational microstructures are linked to the correlation function and determinant of depolarisation matrix, which can be experimentally obtained in three-dimensional neutron depolarisation (3DND). By tuning the parameters in the model used to generate the microstructure, we studied the effect of the (magnetic) particle size distribution on the 3DND parameters. It is found that the magnetic particle size derived from 3DND data matches the microstructural grain size over a wide range of volume fractions and grain size distributions. A relationship between the correlation function and the relative width of the particle size distribution was proposed to accurately account for the width of the size distribution. This evaluation shows that 3DND experiments can provide unique in situ information on the austenite-to-ferrite phase transformation in steels.     

Role of Aging in the Formation of Non-spherical Nanostructures during Laser–Matter Interaction in Water

Optics and Spectroscopy - Pulsed laser ablation of different surfaces in liquid environment has broad prospects to selectively synthesize nanoparticles (NPs) with specific optical properties, as...     

Changes in the Properties of Iron during BCC–FCC Phase Transition

Physics of the Solid State - The thermodynamic properties of bcc and fcc iron phases are calculated at the temperature of the polymorphic bcc–fcc phase transition using the method of...     

Variations of the Frequency Range of HF Signals on the Subauroral Path During Magnetic–Ionospheric Disturbances in October 2016

Radiophysics and Quantum Electronics - We present the results of studying variations of the key characteristics of the ionospheric HF channel, namely, the maximum observed (MOF) and the lowest...     

Empirical study of the scaling behavior of the amplitude–frequency distribution of the Hilbert–Huang transform and its application in sunspot time series analysis

Investigating long-range correlation by the Hurst exponent, H$H$, is crucial in the study of time series. Recently, empirical-mode-decomposition-based arbitrary-order Hilbert spectral analysis (EMD-HSA) has been proposed to numerically obtain without proof a scaling relationship, generated from the amplitude–frequency distribution, related to H$H$. We propose a formalism to empirically study EMD-HSA, to deduce its scaling exponent ξ(q)$\xi \left(q\right)$ from the perspective of EMD-based arbitrary-order Hilbert marginal spectrum (EMD-HMS), and to numerically compare the results with the expected H$H$. EMD-HSA and EMD-HMS experiments show that, by incompletely removing (quasi-)periodic trends, the sunspot series should have an H$H$ value around 0.12.     

Selective spectroscopy of tunneling transitions between the Landau levels in vertical double-gate graphene–boron nitride–graphene heterostructures

The spectral and total electron densities of states in two-dimensional FeAs clusters, which simulate iron-based superconductors, have been calculated using the generalized quantum Monte Carlo algorithm within the full two-orbital model. Spectra have been reconstructed by solving the integral equation relating the Matsubara Green’s function and spectral density by the method combining the gradient descent and Monte Carlo algorithms. The calculations have been performed for clusters with dimensions up to 10 × 10 FeAs cells. The profiles of the Fermi surface for the entire Brillouin zone have been presented in the quasiparticle approximation. Data for the total density of states near the Fermi level have been obtained. The effect of the interaction parameter, size of the cluster, and temperature on the spectrum of excitations has been studied.     

Special Aspects of the Surface Scale Growth during Oxidation of V–Cr–Ta–Zr Alloy in Air

Russian Physics Journal - The results of a study of features of the surface scale growth on the V–Cr–Ta–Zr vanadium alloy specimens during short-term oxidation in air are...     

Effect of interaction in the Ga–As–O system on the morphology of a GaAs surface during molecular-beam epitaxy

A thermodynamic analysis of processes of interphase interaction in the Ga–As–O system has been performed and their theoretical laws have been determined, taking into account nonlinear thermal physical properties of the compounds, the oxide film compositions, and modes of molecular-beam epitaxy of GaAs. The processes of interaction of the native oxide of GaAs with the substrate material and also with Ga and As₄ from a vapor gaseous phase have been studied experimentally. The experimental results correlate with the results of the thermodynamic analysis. The laws of influence of the removal of the proper oxide on the evolution of the GaAs surface morphology under conditions of the molecular-beam epitaxy have been proposed.     

Secondary X-Ray Environment in the Lower Atmosphere of the Earth during Monsoon Season over Udaipur City （India） in July-September 2006

We present a study on the secondary x-rays of energy band 2-100 keV emitted by the intruded principal pollutant components （gases and minerals） brought up in the lower atmosphere by dust storms, monsoon drift and the gravitational pull on meteoritic showers. On the ground we employed a 1.5 × 1 inch^2 NaI crystal in a scintillation detector, suitable for the energy range 2-100 keV of secondary x-rays, providing better energy resolution than a larger sized crystal. In order to eliminate the radioactive background of the Earth, the detector was well shielded on all sides with the help of the lead （Pb） container, except with a.small open window at the top to permit only vertically incident secondary radiation. The results from the data analysis obtained during the monsoon over Udaipur city （India） during the period from July to September （2006） have revealed a linear correlation between dust storm cure monsoon clouds and observed luminosities of secondary x-ray radiation from intruded pollutants. We found intense flux of secondary x-rays from the intruded pollutants when heavy dust and monsoon clouds were brought up by dust storms and monsoon drift in the lower atmosphere over Udaipur city as compared to normal days. Thus, secondary x-rays in the environment provide a tool for investigation of local intrusive pollutant components in the lower atmosphere.     

Resistive switching effects on the spatial distribution of phases in metal–complex oxide interfaces

In order to determine the key parameters that control the resistive switching mechanism in metal–complex oxides interfaces, we have studied the electrical properties of metal/YBa₂Cu₃O₇−δ${\mathrm{O}}_7-\delta$ (YBCO) interfaces using metals with different oxidation energy and work function (Au, Pt, Ag) deposited by sputtering on the surface of a YBCO ceramic sample. By analyzing the IV$\mathit{IV}$ characteristics of the contact interfaces and the temperature dependence of their resistance, we inferred that ion migration may generate or cancel conducting filaments, which modify the resistance near the interface, in accordance with the predictions of a recent model.