The possibility to use instruments of identification measurement theory to solve the problems of diagnostics of fuel cells according to their noise characteristics is considered in this paper. The offered techniques of diagnostic signals processing are based on the identification measurement of time and probabilistic characteristics, the comparison of model signals with the ones under analysis according to the reading values, the classification of signals according to the waveform parameter and characteristic frequency, the building of hierarchical structures, and the assessment of the signal structures by the fractal indices. All proposed techniques are applicable for the diagnosis of a fuel cell, but thanks to graphical representation of classification trees of noise signals, the more efficient method for experts is the one based on the building of hierarchical structures.

This article presents the results of studying the disaggregation of titanium dioxide in water-dispersion compositions based on an acrylic film-forming agent under the action of a surfactant. The possibility of using polyether siloxane copolymer (PC) and sodium polyacrylate (NaPA) in paint and varnish compositions as modifying additives of the dispersing effect is proved. The correlation between the dispersing effect of surfactants and the amount of their adsorption on the pigment is proved. NaPA, which provides a greater reduction in adsorption strength, demonstrates a greater dispersing effect than PC. It was found that the larger the size of the aggregates of pigment particles, the greater the disjoining pressure created by the surfactant. An equation is derived that generalizes the cumulative contribution of surfactant concentration and the content of the film-forming agent in suspensions to the average particle diameter of pigment. The introduction of NaPA in the amount of 0.25 g/dm³ into the paint allows the rate of acid corrosion to be reduced by 2 times, the number of pores in the coating to be decreased, and the adhesion of the coating to be significantly increased (by 2 points according to ISO 11845: 2020).

The aim of this work is to optimize the composition of a two-component silicone enamel consisting of an aluminum pigment and a polyphenylsiloxane polymer to obtain the maximum dispersion of the pigment in the coating. The following products were used as surfactants: AS-1, PEPA, and Telaz. To assess the effect of surfactants on the dispersion of the pigment, computer-optical microscopy was used. The results of the studies showed that all the studied surfactants cause an improvement in the dispersion of the pigment. According to the degree of influence on the dispersion of the pigment, surfactants can be arranged in a row: PEPA > Telaz > AS-1. When the PEPA content in the enamel is 0.25 g/dm³, a decrease in the diameter of the pigment particles by 46% (from 26 to 14 microns) is recorded, with an increase in their specific amount by 2 times (from 258 to 550 pcs). Optimal enamel compositions allow a reduction in the corrosion rate by 11 times (from 0.6 to 0.053 mm/year) and improvement to the decorative properties of coatings (roughness, gloss, etc.). The effectiveness of the AS-1 product (obtained from oil refining waste) as a dispersant additive in silicone enamel has been proven.

This paper reports the results of studying the influence of surfactants (SAS) on the wetting of titanium dioxide in alkyd paint and varnish materials (PVM), based on pentaphthalic (PPh) and alkyd-urethane (AU) film-forming substances. Edge wetting angle (θ°) and adhesion work (Wa) were used as the criteria for assessing the wettability of titanium dioxide. Three additives were used as SAS: the original product AS-1, obtained from waste of oil refining (with low cost), and industrial additives: "Telaz" and polyethylene polyamine (PEPA). All the studied additives in PPh and AU PVM improve the wetting of titanium dioxide. At the 30 % content of AS film-forming substance in the composition, the maximum decrease in θ° for AS-1 is 4.5°, for PEPA and Telaz it is 4°. For pentaphthalic composition under similar conditions, a decrease in edge wetting angle for AS-1 is 10 °, for Telaz 8.6°, and for PEPA 5.9°. According to the relative change in edge wetting angle for both systems, the maximum decrease in θ° is about 10 %. The introduction of SAS into the composition of AU ambiguously affects the adhesion work, for PPh, the introduction of SAS causes a decrease in adhesion work (Wa). AS-1 is the SAS that minimally reduces adhesion work. The compositions of the PVM by the method of probabilistic-deterministic planning, which ensures maximum wetting of titanium dioxide with film-forming solutions, were analyzed. The equations for calculating the edge angle of wetting of titanium dioxide depending on the content of solvent and the SAS in the PVM were derived. The effectiveness of the AS-1 product as a wetting additive for alkyd paints and varnishes was proven. The wetting ability of the original SAS – AS-1 is close to industrial additives PEPA and Telaz.

This paper reports the results of studying the effect of two additives such as polyether siloxane (PS) and sodium polyacrylate (SPA) on the wetting of various substrates in water-borne paints (WB paints). Titanium dioxide (TiO2), paraffin (PA), steel (ST), and glass (GL) were used as solid substrates. The edge wetting angle (θ0) and the ratio (dCosθ/dСS) were used as the criterion for assessing the wettability of solid substrates. In aqueous solutions (without acrylic resin), both surfactants improve the wetting of the substrates. For PS, all the substrates studied, depending on θ depression, can be arranged in a row: ST>PA>GL>TiO2. For SPA: PA>TiO2>GL>ST. The introduction of an acrylic film-forming agent in the composition enhances the wetting ability of SPA (in comparison with the aqueous solution of surfactants). With an increase in the concentration of SPA from 0 to 4 g/dm3 in acrylic resin solutions, the edge wetting angle of steel decreases by 6÷8° (while in water by only 3°). With respect to TiO2, the wetting activity of SPA does not depend on the acrylic content of the water. PS in acrylic-containing compositions exhibits worse wetting activity than SPA. The introduction of surfactants in the compositions improves the quality of coatings. With optimal SPA contents in the compositions, the corrosion rate of coatings is reduced (in distilled water by 45 %, in 60 % NaCl solution by 60 %). At the same time, the gloss of coatings increases by 50 % while adhesion increases by 2 points (according to ISO 11845: 2020). This is fully correlated with the nature of the effect of surfactants on the wetting of the steel substrate and pigment (titanium dioxide). Based on probabilistic-deterministic planning, the compositions of WB paints were optimized, ensuring their maximum wetting of TiO2 and ST. Equations for calculating cosθ depending on the content of acrylic polymer and surfactants have been derived

The aim of this study was to optimize the composition of enamel consisting of aluminum pigment and polyphenylsiloxane polymer, in order to achieve the maximum aggregative stability of suspensions. Sedimentation rate (SR) was used as a criterion for assessing the aggregative stability of the suspensions. An original product, AS-1, and industrial additives PEPA and Telaz, were tested as surfactants. AS-1 was obtained from oil refining waste at M. Kozybayev North Kazakhstan University. All the studied surfactants improved the stability of the suspensions. The AS-1 additive significantly improved the stability of the suspensions, but exhibited a lower stabilizing ability by 10–20% than PEPA. The maximum overall stability of the suspensions was recorded at a PEPA level of 0.25–0.375 g/dm³ in the enamel. The Taguchi method was used to optimize the composition of the enamel, using AS-1 as the surfactant. It is recommended to use AS-1 in silicone enamels. Optimum compositions can reduce the petrol absorption of coatings by 1.5 times, their roughness by 2.5 times and increase their gloss.