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The development and improvement of fluorescent methods for controlling the working properties of a lubricant in tribosystems is an urgent matter. A method for measuring the decay kinetics of the lubricant fluorescence anisotropy of lubricating oil on a FL900 CTD high-speed fluorometer (Edinburgh Analytical Instruments) in the single-photon counting mode is described in this work. Measurements of the attenuation time of fluorescence anisotropy of new and mineral-oil working in hydraulic systems were made. A correlation was established between the decay time of the fluorescence anisotropy of oils and the product of the dynamic viscosity of the oil and the volume of the fluorescent complex, which can be used in laboratory analysis of the performance of oils, and also in creating methods and devices for on-line diagnostics of friction units.

В статье поднимается вопрос об использовании современных информационных технологий в мире деревообработки. Важным показателем освоения земель является уровень развития лесной промышленности. Именно поэтому важно обращать внимание на фирмы данной отрасли. В статье предлагаются новые способы повышения эффективности компаний и разработки комплексного подхода к повышению эффективности управления лесным хозяйством путем внедрения управленческого подхода и использование корпоративных информационных систем, реализующих новые информационные технологии. Российские системы учета в лесной сфере не удовлетворяют растущие потребности предприятия. Что касается увеличения размера и ассортимента продукции, инноваций и технического оснащения, компании необходимо иметь одно комплексное решение для его обслуживания, но при этом необходимо управлять управленческими счетами, относящимися к компонентам предприятия.

Analysis of the ways of improving the inductive method for diagnostics of the wear of tribological assemblies by the wear debris and the current state of the developments of inductive particle counters is performed. It is shown that the inductive counters based on the phenomenon of mutual electromagnetic induction that use three volumetric coils are applied to diagnose heavy loaded assemblies; however, in virtue of their restricted sensitivity to fine particles with sizes below 100 μm, the counters in question are not applicable to early diagnostics of the wear of tribological assemblies that operate under medium load and speed rates. To control the condition of the above assemblies, multichannel inductive counters can be used fitted with double-layer planar coils that record ferromagnetic and non-ferromagnetic wear debris with sizes of ≥75 μm. It is demonstrated that to date the highest sensitivity to ferromagnetic wear debris with sizes of ≥11 μm has been achieved in inductive counters the sensing coils of which have cores. The prospective application of such counters is the control at the early stage of wear of assemblies manufactured of ferromagnetic materials.

One of the early manifestations of atherosclerotic lesions is endothelial dysfunction developing under conditions of reduced nitric oxide production, hyperhomocysteinemia, and oxidative stress. Bearing in mind high interest shown to gender-specific peculiarities of cardiovascular diseases, it appears important to study the relationship between these features in men and women with stable forms of coronary heart disease (CHD). Material and methods. The study included 102 patients with sable COPD divided into 2 groups (men and women) and 40 practically healthy subjects. Plasma homocysteine levels were measured by high-resolution gas-liquid chromatography with fluorescent detector with the use of Eko-Novo Milikhrom A-02 apparatus (Russia). Standard methods were used to measure plasma lipids, products of their peroxidation (dienic conjugates and products reacting with 2-thibarbituric acid), antioxidant enzymes (glutathioneperoxidase, and superoxide dismutase in erythrocytes), activity of the ceruloplasmin-transferrin system (by electron paramagnetic resonance method), final metabolites of nitric oxide using the Gries reaction. The endothelial function was studies by ultrasound with the evaluation of endothelium-dependent vasodilation. Results. The mean levels of homocystein and final NO metabolites in men with stable CHD were 1.5 times higher (р=0,01) and 12% lower (р = 0,03) than in women. Endothelial dysfunction was more pronounced in men (р< 0,05). Conclusion. Patients with CHD exhibit significant gender-specific differences in blood levels of of homocystein and final NO metabolites as well as in endothelium-dependent vasoreactivity associated with intensification of lipid peroxidation and impairment of antioxidative protection.

Mathematical decision-making methods for estimating the state of lubricating oil have been analyzed. It has been demonstrated that the most promising direction for solving problems of determining the performance of oil taking into account the existing uncertainty, ambiguity, incompleteness, and fuzziness of information on the object is the application of an expert system based on fuzzy logic, which provides objective and more substantiated decisions. The intelligent decision-making method on the state of lubricating oil and the structural diagram of the fuzzy logic method based on the Mamdani algorithm have been developed. An example of the implementation of the developed method for monitoring the lubricating oil state has been given based on the analysis of the following diagnostic parameters: total oil contamination measured in three spectral ranges, chemical destruction factor, and oil viscosity. A conclusion has been drawn on oil serviceability based on the analysis of the integrated numerical oil state factor. It has been demonstrated that the developed method provides a real-time objective estimation of oil serviceability and makes it possible to perform the timely maintenance of the tribosystem.

It is shown that in the mineral transformer oil oxidation process the fluorescence spectrum of the oil shifts to the long-wave region. This phenomenon lies at the foundation of the method of determination of the degree of electroinsulating oil oxidation in real time. The oxidation state is determined by measuring the diagnostic parameter, i.e., the oxidation index that characterizes the magnitude of shift of the fluorescence spectrum of the oil upon its oxidation. The oxidation index is defined as the ratio of the fluorescence intensity measured in the longer-wave spectral range to the intensity measured in the shorter-wave spectral range. The results of measurement of the transformer oil oxidation degree by the fluorescence method vis-a-vis other measurement methods, such as titration and IR spectroscopy, are presented. The proposed method can be used to determine the increase in oil oxidation rate at the earlier stage. The device for implementing the developed method can be a portable one or can be installed in the oil-filled system of the equipment.

This chapter presents the methods of monitoring the water content in industrial oils allowing for servicing and prevention of failures of equipment. The most common devices for on-line real time monitoring of the water content in oils are nowadays based on capacitive sensors and polymer absorbing films. Their advantage is in cost-efficiency and simple maintenance. The devices with absorbing elements determine the relative oil saturation with water. Yet, if it is required to evaluate the absolute water content the devices without absorbing elements should be used. It is stated that the development of the reliable sensors installed in the equipment is of urgency. Another important task is to provide the predictive maintenance with controlling the level of water content at a given level providing the long life and reliable operation of the equipment. The laboratory and on-line methods are considered in the chapter and estimation of their validity is given.

This chapter is devoted to monitoring the oil viscosity as one of the major physicochemical factors of quality and efficiency of oil. The review of methods of monitoring the oil viscosity presented in the chapter shows that at present, portable viscometers requiring periodic sampling of oil are widely applied; however real-time on-line monitoring is necessary for the reliable operation of machines. Among the devices mounted directly into the oil circulation lines and, particularly, into the lubrication systems of vehicles, acoustic devices are the most promising. In parallel with solid-state sensors based on acoustic waves, magnetoelastic viscosity sensors are considered; they operate at lower frequencies. Both piezoelectric and magnetoelastic types of the on-line acoustic viscometers have proved to be promising in the real-time monitoring of lubricating oils.

This chapter considers the on-line monitoring in tribology and industrial lubrication. Basic characteristics of oil and laboratory analytical methods are discussed. It is shown that growing requirements to performance of oil promote the development of new methods and instruments for condition monitoring. The devices for on-line monitoring based on the analysis of oil viscosity, dielectric permeability, conductivity, as well as the acid and base numbers are reviewed. Fluorescence emission of oil was used to develop a method and sensor for detecting oil degradation. The concept of this method based on evaluating oil oxidation rate by recording the shift of fluorescence spectrum to the long-wave region is described. Test results for hydraulic oils are compared with the data measured by standard method. The fluorescent method is compared with other techniques, such as the titration method and IR spectroscopy, while measuring the oil oxidation of transformer oil. It is shown that fluorescence emission ratio gives sufficient information for evaluating the oil degradation in real time.

This chapter describes the main trends in tribodiagnostics: development of systems for continuous monitoring; increasing the number of sensors built as standard elements in the oil line of engines, turbines, and other heavy machinery; development of software including methods of artificial intelligence; and reduction of costs of tribodiagnostics promoting its more wide application. Modular systems providing the complete online estimate of the condition and contamination of oil and the wear debris generation are described. Example of a modular Intelligent (SMART) System of vehicle is presented. It has been demonstrated that the most promising direction in determining the performance of oil taking into account the existing ambiguity, incompleteness, and fuzziness of information is the application of an expert system. It can be based on fuzzy logic, which provides objective and more substantiated decisions. The developed intelligent decision-making method and the structural diagram of the fuzzy logic method based on the Mamdani algorithm are described. It is shown that this method provides a real-time objective estimation on oil serviceability and makes it possible to perform the timely maintenance of the tribosystem.

This chapter considers the control of the oil contamination, by products of incomplete combustion (soot). Up-to-date requirements which set the necessity of development of portable monitoring devices built in the car lubrication system are considered. Laboratory methods, as well as portable and built-in devices, designed for control of soot concentration in oil, are analyzed. It is shown that the novel built-in devices for monitoring soot concentration are of urgency for diesel engine reliability improvement. The measuring systems for on-line monitoring the soot content in vehicles with diesel engines are described. They are based on measuring the soot electrical and optical properties. Advantages and shortcomings of these devices are considered and the prospects of practical applications are discussed. Most challenging way of development of on-line methods for monitoring the soot content in diesel oil is the usage of fiber optic detectors, which are not impacted by electrical noise and disturbance. Basics of fiber-optic detectors and calculation of their parameters are described. Design and laboratory test results of the fiber-optic soot detector are presented.

The chapter considers the predictive maintenance of machines and mechanisms basing on wear debris analysis because they relate to the mode and severity of wear. Review of laboratory, portable and on-line wear monitoring techniques based on wear debris analysis is presented. It is shown that if it is necessary to have maximal information on the wear particles it is advisable to use the laboratory methods. The complex built-in systems are justified for use in expensive and critical equipment (e.g. airplanes and helicopters).When complete information on the wear particles is not required, the simpler and less expensive field diagnosis methods are suitable. It was found that the magneto-optical field methods are the most promising. The portable and on-line versions of Opto-Magnetic Detector (OMD) are described. The operation of OMD is based on variation in optical density of oil containing ferromagnetic particles under the effect of magnetic field. OMD has been used in wear monitoring of industrial air compressor system for two years and it was found very sensitive to failure of the gear unit and metal bearings presenting earlier information on severe wear of friction units than vibration monitoring. Description of the Optical Ferroanalyzer is presented which in addition to Ferrograph allows one to estimate total contamination of the oil, increasing reliability of engine condition monitoring.

The study of the effect that the molecular weight and concentration of the polymer gelling additive PMMA (polymethylmethacrylate) introduced into the synthetic base oil PAO6 has on viscosity. The empirical dependence of the viscosity of the thickened oil on the content of additives has been established and the coefficients of the thickening efficiency of additive have been determined. An experimental study of the viscosity of synthetic oils on the shear rate has been carried out at different contents of viscosity modifier PMMA with different molecular weights in a base of PAO6. The ranges of velocities have been determined at which the oil exhibits properties of non-Newtonian fluid. It has been shown that, with an increase in the molecular weight of PMMA of additive at the same concentration in its base, the non-Newtonian behavior of oil begins to emerge at lower shear rates. It has been found that the use of an acoustic arsenal of the operational control of the viscosity of lubricating oils based both on the piezoelectric and the magnetoelastic interaction is promising for the operational control of the viscosity of lubricating oils.

A method is developed for quick oil-quality and performance monitoring by simultaneous determination of the oil’s total impurity content based on optical density in the red, green, and blue wavelength ranges, as well as the chemical properties based on the difference in the chromatic ratios and oil color in TCU ( true color units). This method can be used to determine the quality of fresh oil during its production, monitoring the incoming oils before their use in equipment, and make prompt evaluations of the oil’s performance in the course of tribojunction use.

Dynamics of fatty acid composition of total lipids was studied for freshwater salmon Salmo salar L. during its embryonic development from blastula (3 hours) up to hatching (108 days) as well as in unfertilized eggs. Stable amount of total and some saturated, monounsaturated and polyunsaturated fatty acids (PUFA) of total lipids was observed during embryonic development. Considerable changes in fatty acid composition were observed at the stage of prelarvae hatching, i.e., significant decrease of (n-6) PUFA (18:2(n-6) and 20:4(n-6)) and (n-3) PUFA and increase of total and some saturated and monounsaturated fatty acids was registered. Change in saturation ratio of membrane lipids justifies the presence of the biochemical mechanism forwarded on regulation of cell membrane enzymes in accordance with the changes of internal physiological processes taking place in the organism and fluctuations of external environmental conditions or the preparation period (as reproduction). Data on peculiarities of transformation and utilization of fatty acids during salmon embryonic development may be used for understanding of their functional role in the developing organism as well as for assessing the quality of the caviar.

This work discusses composite coatings obtained by electro-spark alloying and self-propagating high-temperature synthesis. It has been established that the generated composite coatings consist of titanium carbides, which are uniformly distributed in the metal matrix. The titanium carbide grain sizes are in the range of 0.1–4.0 μm. The coarse grains of titanium carbide in the coating consist of disperse carbides with sizes of less than 1 μm. The study of the structure of the composite coatings in friction tracks has demonstrated that the generated coatings possess high wear resistance.

It has been shown that the phase transitions observed at temperatures of about 250 K in crystals of protein amino acids and of their compounds grown from water solutions are related to drops of these solutions trapped by crystals in their growth.

The dielectric and magnetic measurements of the KMnF3 crystals obtained by the Czochralski and Bridgman methods have been performed. Three structural transitions have been observed in the crystals. The mutual arrangement of the temperature of magnetic ordering and the temperature of the lower structural transition determines the number and type of magnetic transitions in these crystals.

The paper describes the theoretical standpoints of developing magnetoelastic viscometers and a concept of viscosity measurement. The magnetoelastic viscometer has shown the readings close to the capillary viscometer. Testing of the oils with PMMA viscosity-index improvers by viscometers has indicated changes in rheological properties observed in the non-Newtonian behavior of the oils. With increase in content or molecular weight of the improver, the non-Newtonian behavior of the oil appeared at lower frequencies of viscosity measurements.

The paper discusses the prospects for developing means for on-line measurement of the viscosity of lubricating oils, including diagnostic instrumentation based on magnetoelastic interaction. The theoretical basis for the development of magnetoelastic sensors and the main concept of measuring the fluid viscosity are presented. Two methods of measuring the viscosity are described. The first method is based on estimating variations in the natural frequency of oscillations of a sensitive element and the second involves analysis of the decay rate of the amplitude of oscillations. The design of the developed magnetoelastic sensor and the experimental results of comparing the two measurement methods are reported. The paper also presents the comparative results of measurement of the oil viscosity by a magnetoelastic sensor, a capillary viscometer, and a solid-state piezoacoustic sensor. It is shown that the reliability of the magnetoelastic sensor is high from the viewpoint of on-line monitoring; owing to its relatively low cost and ease of maintenance, it has wide potential for application in monitoring of lubricating oils in tribosystems.

An analysis of the features of variation and monitoring of the oil viscosity during tribosystem operation is presented. Methods and means for on-line monitoring of oil viscosity are reviewed, which allow on-line monitoring of the state of machinery and equipment. It is shown that the development of means for on-line measurement of viscosity based on the method applied under laboratory conditions does not meet the requirements for miniaturization and reliability of the diagnostic devices. To solve this problem, vibration methods of monitoring based on the application of tuning forks and microcantilevers are proposed. Among devices mounted directly into oil circulation lines, and, particularly, into lubricating systems for vehicles, acoustic devices have the most promise.

The effects of docosahexaenoyl dopamine and docosahexaenoic acid on the regeneration of hydra gastric and basal fragments are studied. Docosahexaenoyl dopamine induced morphogenetic abnormalities such as single ectopic tentacles in the gastric region and projections in the gastric and basal regions. Docosahexaenoic acid had no effect on the morphogenesis except for a mild slowing of the regeneration rate. Since no hydrolysis of docosahexaenoyl dopamine was detected in hydra extract, it was assumed that the morphogenetic effect could be associated with the dopamine component of this complex.

2-(1,3-Diaryl-3-oxopropyl)cyclohexan-1-ones underwent carbo-and heterocyclization in a mixture of acetic acid with acetic anhydride in the presence of perchloric acid. The transformation of 2-(1,3-diaryl-3-oxopropyl)cyclohexan-1-ones into 2,4-diaryl-5,6,7,8-tetrahydrochromenylium salts was shown to involve intermediate 2,4-diarylbicyclo[3.3.1]non-2-en-9-ones. The structure of 2,4-diaryl-substituted bicyclo[3.3.1]non-2-en-9-ones and products of their reactions with halogens and hydroxylamine hydrochloride was confirmed by 1H and 13C NMR spectroscopy.

A miniature integral detector is presented that enables in-line monitoring of the lubricating material in trybosystems by measuring and evaluating four diagnostic parameters simultaneously: chemical disintegration, total contamination content in the oil, water content, and temperature. The detector comprises a self-test system, self-tuning controlled by a microcontroller. The diagnostic parameters of the detector and the standard parameters, such as viscosity and general acid number of mineral and synthetic oils, are compared for their analysis. The validity of the detector’s output data is confirmed, which assures its broad application for in-line assessment of the performance of the oil and condition of the tribosystem in general given the high information content and the level of computerization.

Intrinsic fluorescence emission of oil was used to develop a technique and detector for evaluating oil degradation. Test results for hydraulic oils with and without zinc dialkyldithiophosphates additives and calcium-based dispersant were in conformance with the results of optical emission spectrometry, particulate counts, optical microscopy, total acid number, and viscosity tests. The ratio of intrinsic fluorescence emission was found to be a parameter independent of the concentration of dust and iron contaminants in non-additive oil. It proved to be dependent on oil chemical degradation, becoming a tool to detect degradation before incipient wear at the tribological interface becomes relevant. The study showed that intrinsic fluorescence emission ratio gives sufficient information to characterize and evaluate oil degradation.

The method is proposed for determining the microhardness of thin coatings by scratching. Atomic force microscopy was applied to determine the scratch width and the optimal load on the indenter. Combined coatings 4 μm thick based on Ti, Cr, Mo2N, and alloy ZrHf obtained by the combination of electric-arc evaporation and ion nitridizing were studied. The combined coatings are shown to have better micromechanical characteristics compared to the nitride coatings deposited by the electric-arc evaporation of these refractory metals and alloys.

Current interest in evaluating the oil condition in tribosystems is discussed. Fluorescent express-methods for oil condition monitoring are analyzed and their main advantages and disadvantages are noted. The basic concept of the fluorescent method developed for evaluating oil oxidation rate by recording the shift of fluorescence spectrum to the long-wave region is described. The realization of the method is exemplified and the results of the analysis of fresh and worked hydraulic oils with the developed fluorescent sensor are given. The sensor can be used as both built in the oil line and a portable device under manufacture and laboratory conditions.