Properties of the surface layer of corrosion resistant Cr - Ni - Ti steel formed under the technological impact of argon plasma are considered. Methods of atomic emission spectrometry with glow discharge, x-ray microanalysis and Auger spectroscopy are used to demonstrate that the impact of argon plasma promotes redistribution of the elemental composition in the surface layer of the alloy, most notably in the nanoscale surface region.

A simple method of sample preparation, rapid screening and determination of 17 dyes (E labeled food additives) in food products using HPLC/quadrupole-TOF mass spectrometry of high resolution is developed. Sample preparation of solid samples consists in solid-liquid extraction with acetonitrile, 2-fold dilution of the extract in deionized water, filtration, and chromatographic run. As for beverage the procedure consists in centrifugation, 10-fold dilution, filtering, and chromatographic run, respectively. The detection limits range 0.1 - 300 ng/g. A scheme of screening and determination of synthetic dyes in food which includes dye identification by the exact ion mass (m/z ), retention time, coincidence of isotopic distribution mSigma and determination of the dye (if present) by the standard addition method (spiked test). The relative standard deviation of the results of the analysis did not exceed 0.1. Duration of the analysis is 0.5 - 1 h.

Physico-chemical methods are used to study complex formation of iron (II, III)with dimercaptopropanes (2,6-dimercaptopropane, 2,6-dimercapto-4-methylphenol, 2,6-dimercapto-4-ethylphenol and 2,6-dimercapto-4-tert-butylphenol) and hydrophobic amines (heterocyclic diamines 1,10-phenanthroline, 2,2'-dipyridyl and 4,7-diphenyl-1,10-phenanthroline. Optimum conditions for formation and extraction of mixed ligand complex compounds and ratio of the components in the complexes are specified. Mixed ligand complexes (MLC) are formed in weakly acidic media (pH_opt = = 5.2 - 7.5), maximum in MLC spectrum of the light absorption being observed at λ = 552 - 586 nm, molar absorption coefficient ε = (3.08 - 4.40) x 10⁴. Photometric methods of iron determination developed for the vatiety of objects exhibit good reproducibility and low detection limits.

Apossibility of applying amperometry for determination of lactic acid (LA) based on the inhibition of the molybdenum (VI) recovery and amperometric titration with registration of the diffusion current of lactic acid recovery on a platinum electrode is demonstrated first-ever. We evaluated the impact of different organic acids and other factors on the current value and specidied working conditions of the amperometric determination of LA. Proceeding from the results thus obtained we developed the methodology of lactic acid determination in in veterinary preparations and blood serum. The determinable concentrations range within 3x10⁵-1x10¹ mol/dm³ (Sr no more than 15 %). Correctness of method is confirmed in spiked test.

A method of measuring magnetic permeability of the materials in the alternating electromagnetic fields is used to study the properties of different steels. It is shown that the magnetic permeability depends on the purity and chemical composition (grade) of steel, as well as on the structure of the material. Samples of structural steel are used in the experiments in condition as supplied. The results are presented in the complex plane as the graphs illustrating the dependence of measured values on the exciting frequency. The measurement procedure and experimental setup are presented.

Firing of magnetite iron ore pellets is shown to be accompanied by a set of physicochemical processes and oxidation of magnetite and carbonate decomposition occurring with exo- and endothermic effects are the most important among them. It is also shown that optimization of pellet heat treatment necessitates determination of the temperature intervals and duration of the processes along with the degree of their completion. This data array provides efficient distribution of the air-gas flows along the length of the burning conveyor machine taking into account the internal sources of heat Experimental gravimetric setup is used in studying kinetics of in-plant firing of Kachkanar pellets to elaborate and specify the optimum regimes of their heat treatment. The developed method can be used at various mining and processing plants of the country.

The results of studying the mechanical characteristics (microhardness, bending strength, abrasive wear resistance) and durability of VK6, VK8, T5K10 hard alloy specimens after volumetric pulse laser hardening (VPLH) are presented. It is shown, that x-ray diffraction analysis can be used for selection of optimal hardening modes (energy and duration of laser impulse, laser beam diameter, distance between irradiation point and major cutting edge), thus providing significant reduction of the material consumption, time and costs of laboratory testing. Methods of mathematical statistics are used for comparative analysis of the results and estimation of their reliability.

The use of asymmetric perturbations in a cylindrical cavity resonator with the fundamental vibration H₀₁₁ for determination of the thickness and dielectric constant of coating on the metal surface is considered. Spatial fluctuations of the electric field H₀₁₁ are analyzed by finite element method using COMSOL Multiphysics program for empty and perturbed cavity. An original experimental unit with a P2M-18 scalar meter is used in the study. The resonator design provided filtering of spurious vibrations. Different variants of measuring schemes with perturbed and empty cavities are considered to verify the developed method.

Method of statistical simulation (Monte Carlo method) is used to determine the brittleness transition temperature Tk according to the procedures PNAE G-7-002-86 and RD EO 0598-2004 in the numerical experiments. Data of bending impact test of Charpy specimens (with V-notch) used in the calculation are obtained on an array of more than 1200 steel samples (15H2NMFAA) cut from different (in thickness, height and in the circumferential direction) zones of the VVER-1000 reactor shell within a temperatures range of -95 to +20°C. Data of statistical tests indicate that the material of the reactor shell can be considered homogeneous. It is found that the values of sample fracture in the brittle-ductile transition region obey the bimodal law, parameters ofthe distributions being determined at different temperatures. Statistical modeling revealed the laws of the transition temperature distribution. It is shown that the average Tk values determined from PNAE G-7-002-86 exceed the values determined from RD EO 0598-2004 approximately by 10°C. The boundaries of the intervals wherein the values of the transition temperature are located with 90% probability depending of the number of tested samples and test pattern are determined. Recommendations for improving the methodology of the transition temperature determination are specified.

Features of quantitative evaluation of the Bauschinger effect in magnesium alloys with an asymmetry of deformation behavior regarding tension and compression are considered. It is found that the Bauschinger effect is associated with different contribution of detwinning in total strain in different loading directions. A quantitative evaluation of this effect using stress- and work of deformation approaches renders very close results. The asymmetry of deformation upon tension and compression in magnesium alloys similarly affects both the yield stress and deformation contribution of detwinning in total plastic strain. Parameters of the Bauschinger effect are close to zero when the first loading excursion is in compression, which means this effect is very weak and inelasticity is mostly connected with the twinning process upon tension. The comparison of the Bauschinger effect for commercial ZK60 and promising Mg-based ZE10 (alloyed with rare earths) engineering alloys univocally points to better properties ofthe latter.

The specific features of deformation of layered composites and problems of strength estimation attributed to them are considered. Here we focuse on the edge effect occurring on free edges of composite structures. The mechanism of the edge effect formation is considered in the case study of a composite plate with a circular hole loaded by pure shift. It is shown that the edge effects can be responsible for premature delamination of the composite package. The results of parametrical study of the edge effects are presented for 3D models of the plate. The assessment of influence of a stacking sequence of the composite package on the values of delaminating stresses is presented.

Two problems attributed to the features of application of simulation modeling to the study of complex engineeting systems are considered. One of them is related to the goal of improving the efficiency of the Monte Carlo method in modeling of rare events: combination of stratified sampling with equally weighted simulations can significantly speed up the analysis of algorithmic models of stochastic systems by simulation. Solution of the other highlighted the problem related to the inadequacy of using the same generator of pseudorandom numbers upon comparison of sample queue values obtained in the simulation models and fractal classical queuing system.

We present the results of statistical modeling which characterize the dependence of the time to reach a consensus on the number of members of the technical committees on standardization (TC) and their authoritarianism using a mathematical model of consensus-provision based on the model proposed earlier by De Groot. The main problems of attaining consensus in developing consensus standards in the framework ofthe proposed model are analyzed. It is shown that the increase in the number of TC and authoritarianism experts negatively affects the time to reach a consensus and increases dissociation ofthe group.

This note is a comment on the article by I. Z. Aronov and O. V. Maximova published in this issue. As the activity of technical committees on standardization is a form of expert procedures it can be considered in the framework ofthe theory and practice of expert estimation thus making “consensus” a problem of consistency of expert opinions of the members of expert committee. However, the purpose of the expert committee is not to achieve harmonization of opinions (consensus), but to elaborate (as a collective opinion) the conclusions matching the reality and usually aimed at developing reasonable management decisions, in short, to find out the truth. Here we discuss the correspondence between consensus and truth.