Physical and Technical Foundations of the Use of Alternating Free Bending for Producing Long-length Semi-products from Metals and Alloys with Improved Mechanical Properties

In this work, we give a theoretical justification of the non-monotonic character of strain in the process of refinement and formation of a grain-type structure during the deformation processing of low-alloyed copper heat-hardenable alloys. A regularity is revealed, suggesting the alternating behavior of the strain state in the process of the continuous bending of billets. It is found that the continuous free bending process in the conditions of multi-cycle (four cycles) processing increases the strength and produces a gradient-type structure and a gradient of mechanical properties. Using fabrication of the experimental samples of the contact wire as an example, it is shown that the obtained results can serve as a scientific and technical foundation for the development of complex methods for the processing of axis-symmetrical long-length objects from copper heat-hardenable alloys in the form of wires and shaped products with improved mechanical properties, with potential adaptability for manufacturing.

Extraordinary Properties of Alcohols from the Homologous Series of Methanol

Non-trivial properties of thermodynamic quantities such as the density, the critical and triple point temperatures, and their ratio, as well as the optical and dielectric properties, have been analyzed for primary alcohols from the methanol series. The aim is to reveal relationships among their values measured at the same temperatures for alcohols with different ordinal numbers m’s in the methanol series. It is shown that the non-monotonic character of the temperature dependences of alcohol densities is associated with methanol rather than ethanol, as may seem at first glance. The critical temperature of methanol also deviates from the quasilinear dependence of the critical alcohol temperatures on m. With the growing m, the ratio between the critical and triple-point temperatures for alcohols is shown to tend to the corresponding value for water. Simple linear dependences of the electronic and effective static polarizabilities of alcohol molecules on m are established. The transverse and longitudinal components of the polarizability tensor for alcohol molecules are found. The dipole moments of the closest neighbor molecules in the alcohols are proved to anticorrelate, i.e. to orient in opposite directions.

ANALYSIS OF THE DEFLECTION OF A TRUSS WITH A DECORATIVE LATTICE

Introduction. A scheme is proposed for a planar symmetric statically determinate beam truss with a rectilinear lower belt, struts, multidirectional braces and a polygonal outline of the upper belt. The belts of the truss are rectilinear, the hinges are ideal. The truss belongs to the class of regular trusses having periodic cells. The supporting rods are not deformable. The truss is evenly loaded around the nodes of the lower belt. Materials and methods. The task is to deduce the dependence of the deflection of the truss on the number of panels in the span. The deflection is obtained from the Maxwell-Mora formula under the assumption that all the rods have the same rigidity. Forces in the structural rods from the effective uniform load and from the unit vertical in the middle of the span are determined by the method of cutting the nodes. The matrix of the system of linear equations of node equilibrium is made up of the cosines of the forces with the coordinate axes. To compile a system of equations and solve it, the program of symbolic mathematics Maple is used. To obtain the general formula, a number of problems of trusses with a number of panels from 2 to 29 are solved. Sequences of the coefficients of the deflection formula have common terms for which homogeneous recurrence equations are also compiled using the methods of the Maple system using specialized operators. Results. The solutions of recurrence equations have the form of polynomials with coefficients that depend on the parity of the number of panels and contain trigonometric functions. The graphs of the solutions obtained are constructed and analysed. Sharp changes of deflection characteristic for such truss and their non-monotonic character are noted. It is shown that for a fixed, independent on the number of panels, length of the span and the total load, the relative deflection with increasing number of panels first decreases, then varies little. Conclusions. The asymptotic property of the solution is obtained by the methods of the Maple system: an inclined asymptote is found. The slope is calculated using the analytical capabilities of Maple. A simple formula is derived for the horizontal displacement of the mobile support from the action of the load. The dependence is monotonic. The height of the truss is included in the denominator of the formula.

Generation of Gravity Waves by Singular Potential Vorticity Disturbances in Shear Flows

The linear mechanism of generation of gravity waves by potential vorticity (PV) disturbances in flows with constant horizontal and vertical shears is studied. The case of the initial singular distribution of PV, in which the PV is localized in one coordinate and is periodic with respect to other coordinates, is considered. In a stratified rotating medium, such a distribution induces a vortex wave (continuous mode), the propagation of which is accompanied by the emission of gravity waves. To find the emission characteristics, a linearized system of dynamical equations is reduced to wave equations with sources that are proportional to the initial distributions of PV. The asymptotic solutions of the equations are constructed for small Rossby numbers (horizontal shear) and large Richardson numbers (vertical shear). When passing through the inertial levels symmetrically located with respect to a vortex source, the behavior of the solutions for wave amplitudes radically changes. Directly in the vicinity of the source, the solutions are of monotonic character, corresponding to a quasigeostrophic vortex wave. At long distances from the source, the solutions oscillate. The horizontal momentum flux and the Eliassen–Palm flux are estimated using asymptotic solutions. It is found that, within the indicated range of both Rossby and Richardson numbers, these fluxes are exponentially small: that is, the emission of waves is weak.

The Effect of the Thermal Introduction of NaNO2 on the Optical Properties of Indium and Gallium Monoselenides

The effect of the thermal introduction of NaNO2 on the optical properties of indium and gallium monoselenides was investigated. The transmission spectra of InSe and GaSe and their NaNO2-intercalates were identified by means of the installation spectrometric collected on the basis of monochromator MDR-23. It was found that the time dependence of the concentration of NaNO2-intercalates has the non-monotonic character with areas of different intercalation speeds.

An Unorthodox Parametric Measure of Information and Corresponding Measure of Intutionistic Fuzzy Information

A new parametric function va(p)= log (1+a) - Σlog((1+api)/pi)-1,a>o is proposed for the probability distribution p1p2p3… … … pn and its properties are studied. In this paper the given functions is twice differentiable and is used to obtain the related measure of directed divergence, measure of intutionistic fuzzy entropy, measure of intutionistic fuzzy directed divergence. We also investigate the monotonic character of the proposed function.

Temperature and Thickness Dependences of Thermoelectric Properties of PbS/EuS Bilayers

ABSTRACTA non-monotonic character of the dependences of the thermoelectric properties of PbS/EuS/(001)KCl heterostructures on the PbS layer thickness d (d = 2 – 200 nm) was detected. Pronounced extrema at d ∼ 15 nm and less distinct extrema at d ∼ 30 nm and d ∼ 100 nm were observed. It is suggested that the complex character of the dependences is caused by the competition between percolation phenomena and size quantization. The critical exponent for the electrical conductivity (t = 1.6 ± 0.15) is determined.

An inequality for Mill's ratio for the type III population

Mills(7), Gordon(5), Birnbaum(1), and the author(6) have studied the ratio of the area of the standardized normal curve from x to ∞ and the ordinate at x. Des Raj (4) established the monotonic character of, and obtained lower and upper bounds for this ratio for the standardized type III population. This ratio, as shown by Cohen (2) and Des Raj (3), has to be calculated for several values of x when solving approximately the equations involved in the problem of estimating the para-meters of type III populations from truncated samples. When the areas and ordinates are small, either this ratio cannot be obtained from existing tables prepared by Salvosa(8) or that very few significant digits are available for its calculation. The object of this note is to obtain an upper bound which could satisfactorily locate this ratio over the range x > −1.