Obtaining of Detonation Diamonds from Individual Explosives

Combustion, Explosion, and Shock Waves - A method of obtaining detonation nanodiamonds from tetryl by means of blasting the latter in a water shell with the explosive/water mass ratio of...     

The process of electrochemical deposition of zinc in the presence of boron-doped detonation nanodiamonds

The influence of detonation of nanodiamonds doped with boron during the detonation synthesis (DND-boron) on the process of electrochemical deposition of zinc from a zincate electrolytic solution is investigated. It is shown that the throwing power (the coating uniformity) increases 2to 4-fold depending on the DND–boron concentration, the electrolytic conductivity remains unchanged, the corrosion resistance (as measured by the corrosion currents) of the Zn–DND-boron coating grows 2.6 times when tested in the 3% NaCl solution and 3 times in the climatic chamber.     

Electroreduction of the tantalum oxofluoride complexes in an equimolar mixture of sodium and potassium chlorides

The electrochemical behavior of the tantalum mono-, di-, and trioxofluoride complexes in the equimolar NaCl–KCl melt is studied. The trioxofluoride TaO₃F^2– complexes are shown to discharge at the potentials that are more negative than those of alkali metal cations; that is, they are electrochemically inactive against the background of the equimolar mixture of sodium and potassium chlorides.     

Ultrasonic Testing for Defects in Complex Shaped Metal Products

Russian Journal of Nondestructive Testing - Automation is a topical issue in the development of methods and equipment for ultrasonic nondestructive testing. The conditions of modern industrial...     

Applying the Algorithm of Calculation in the Frequency Domain to Ultrasonic Tomography

Applying ultrasonic-tomography systems makes it possible to precisely determine the shape and dimensions of flaws with the aim of establishing the degree to which the flaws influence safe operation of tested objects. This problem is solved by using special algorithms that make use of echo-signals recorded by an ultrasonic transducer to generate synthesized images of flaws in the sample. The use of phased arrays in ultrasonic tomography is explained by their ability to provide exhaustive data about the internal structure of a test object, thus allowing formation of the high-quality synthesized images of flaws in the object. Increasing the speed of ultrasonic tomography by using phased arrays necessitates the development and implementation of fast data-processing algorithms. In this connection, of interest are calculation algorithms in the frequency domain, which ensure the high speed of producing synthesized images. An ultrasonic-tomography algorithm is proposed that is based on calculations in the frequency domain. The algorithm takes the complex nature of the propagation of ultrasonic waves into account and is connected with the presence of media with different acoustic properties (e.g., in the case of immersion tests). Possibilities offered by the algorithm are investigated by computer simulations using the licensed CIVA 2016 software package and experimentally.     

Structure of Al-Ti-C master alloys

A binary Al-Ti master alloy of hyperperitectic composition, whose structural characteristics ensure high modifying efficiency, has been prepared by the aluminothermy method. The treatment of the alloy by low-frequency vibrations (LFVs) and its interaction with the carbon emitter of LFVs in the process of crystallization lead to the formation of a ternary Al-Ti-C alloy containing titanium aluminide Al₃Ti and titanium carbide TiC. The presence of these phases creates favorable conditions for the formation of solidification nuclei in the aluminum melt when using a ternary master alloy as a modifier. A comparison of the efficiency of the structure refinement when using experimental master alloys and the standard Al-Ti master alloy poured into a metallic chill mold has been performed.     

Petroleum impregnating and protective materials for railroad cross ties

Almost all wood materials — for construction and repair of railroads, for the mining industry, for telephone and electric power poles — must be protected from rotting, that is preserved to increase the lifetime. The Russian economy is suffering enormous material losses because of the insufficiently serious attitude toward this problem. Translated fromKhimiya i Tekhnologiya Topliv i Masel, No. 5, pp. 8 – 9, September – October, 1999.     

Topology of isoenergetic manifolds in feed composition simplexes for extractive distillation

The topology of optimality regions and that of the isocriterial manifolds separating these regions have been investigated for extractive distillation of three-component azeotropic mixtures. The number of topological invariants has been determined for isoenergetic manifold distribution structures in the case of the optimization criterion function having no second-order curvature.     

Aggregative Stability and Thermal Stability of the Petroleum-Based Biocide ZhTK

We present the results of a laboratory evaluation of the aggregative stability (resistance to stratification and sedimentation) and the thermal stability (constancy of the main qualitative index: the viscosity upon prolonged heating) of a new ZhTK petroleum biocide for impregnation of wood cross ties and timbers, in order to protect them from damage by molds and bacteria.