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The reliability and performance of technological equipment largely depends on timely and reliable diagnostics of less durable assembly units, which include rolling bearings. An effective tool for determining state of the mechanical rotational systems on rolling bearings is vibration diagnostics. The variety vibration diagnostic method which are used on practise is due to the complexity extracting an informative component for estimation and predicting the state of rolling bearings from the general vibration signal of the study unit. The article is dedicated information content study of narrow frequency ranges of the vibration signal operation bearing assemblies paper machines and their use as diagnostic parameters for vibration diagnostics of rolling bearings. The paper presents the analysis results of vibration diagnostics existing methods of bearing assemblies of the technological equipment and establishes the determination defects in rolling bearings by changing the vibration level on the characteristic frequencies components of the vibration spectrum and the bypass spectrum provides more specific information about the nature damage of the bearing and its operation. On the processing experimental data base i.e. the average vibration velocity spectra signal taken from the bearing assembly paper machine, we offer a relative indicator for current state bearing estimation and its state prediction progress, which helps to make a decision on the suitability or unsuitability bearing.

The article highlights that in the space of modern design and artistic and creative education, in particular decorative and applied arts, the importance of paper is growing as both a creative material for modelling and for creating artistic products, and at the same time, the paper is simultaneously one of the most accessible art materials both from the viewpoint of ease of use and cost, and paper craft is an important basis for students' perception and creation of more complex artistic forms of professional art. It is noted that despite various editions, this disparity does not allow fully revealing paper-making as a conceptual whole – in the diversity of its connections with project culture, creative laboratory and design methodology in design. The purpose of the article is to reveal paper-making in the space of decorative and applied arts as well as to identify its theoretical and methodological foundations and to substantiate the role of paper-making in modern design for the formation of students' creative thinking alongside the formation of their artistic and pedagogical skills. These methods were applied and used to reveal the problem: general scientific (analysis, synthesis, generalization, systematization); scientific and specific: historical, artistic, pedagogical, psychological and approaches: systemic-structural, structural-functional, comparative, with the help of which the opinion regarding the phenomenon of paper-making is generalized, its essential content is clarified in the plane of decorative and applied arts, in modern design, and methodical methods are specified principles to the problem regarding the development of creative thinking of students specialized in artistic and pedagogical mastery. In the main content, it is noted that on the basis of methodological provisions and basic principles of traditional craftsmanship, the creative and essential foundations for decorative and applied arts are manifested, which ensures the formation of components of artistic competence and, at the same time, requires the use of students’ creative and figurative thinking. The idea of the key figurative-essential basis for paper-making is provided and it is noted that mastering the specifics of artistic imagery forms students' aesthetic ideas as well as a valuable act of understanding the world. It is highlighted that "paper plastic" also reflects the specificity of the author's approach to the study of compositional, constructive, structural and technological regularities of the work with material. In the content of the Methodological recommendations for conducting practical lessons, it is emphasized that the result should reflect the student's mastery – from the initial sketch through full-scale sketches to the design of the idea in the material. It is justified that in addition to the traditional methodical principles of education, there is a need to use certain art technologies. It is emphasized that the implementation of the developed "Conceptual Technology" in the teaching space of paper-making contributed to the decision-making process regarding the means of creating an artistic image. In the conclusions, it is noted that paper-making as a type of activity occupies an intermediate position between learning and playing and meets the conditions that ensure the effectiveness of the development of creative activity. Learning and practical work in the technique of papier-mâché using papier-mâché is important for the formation and development of abstract, associative, combinatorial, logical thinking, in the process of learning "paper-mâché" the creative thinking of students is formed and the skills of stylization and generalization are acquired, which involves the acquisition of practical experience for figurative reproduction. In the perspective of further research, it is important to consider the need to research, develop and create a model for the development of the future designer’s artistic and creative competence.

Subject and Purpose. Results are presented of the solar corona investigations performed with the world famous Ukrainian radio telescopes. The work has been aimed at offering a consistent review of recent achievements in observations of a variety of low-frequency radio emissions from the Sun. Methods and Methodology. The studies of the quiet (thermal) and sporadic (burst-like) radio emissions from the Sun have been carried out with the decameter-wavelength radio telescopes UTR-2, GURT and URAN-2. Specific features of the low-frequency solar radio emissions from a variety of sources are presented, with characterization of the optimized techniques that were applied in each case for evaluating physical parameters of the corona in the areas of decameter-wavelength radio wave generation. Results. The analysis of temporal, frequency and spatial characteristics of solar radio emissions has allowed suggesting a number of models for the coronal electron density distribution, and evaluating magnetic field strengths in the corona. Also, our experimental results have proven to be consistent with the observational data obtained in different frequency ranges and with the use of both ground based and space-borne instruments. Conclusions. The radio observations performed with Ukrainian radio telescopes have permitted studying, with high temporal, frequency and spatial resolutions, solar radio frequency emissions from various localized sources. Along with the large effective area and high sensitivity of the antennas, this permits application of a wide range of methods and tools aimed at detecting and analyzing solar bursts, of both strong and weak intensity, against the background of terrestrial interference of natural or artificial origin.

In this work, four waste paper composites were studied in terms of several photon interaction parameters over the energy region from 0.015 to 15.0 MeV. The waste paper and natural rubber (WP/NR) composites of different densities ranging from ρ = 0.894 to 1.16 gm⋅cm-3 were used for shielding radioactive rubble at different time period stages. Some additives were also used including high-abrasion furnace black, paraffin wax, B4C, as well as magnetite. The deduced parameters of photon interaction: equivalent atomic number Zeq, exposure buildup factor and energy absorption buildup factor have been studied as a function of incident photon energy, WP/NR elemental composition, and for penetration depths, up to 40 mean free path. The Zeq numbers have shown slight variation over the selected incident energy range and buildup factors were found to be modest at low and high photon energy meanwhile their values increase widely over the intermediate energy region. In addition, kerma relative to air for photon energies from 1 to 20 MeV were computed and show dependence upon equivalent atomic numbers. In this work, it was clear that filled samples offer better shielding capabilities than unfilled ones. The obtained data could be useful for radiation physicists and scientists in estimating the γ-irradiation received after applying such shields.

Purpose. To substantiate the breakdown mechanism of capacitor paper on the basis of numerical-field models with segmented cross-sections of cylindrical volumes of air and water, and also use the proposed models to determine the breakdown strength of air in micron-sized gaps under normal conditions. Methodology. The model bases on a finite element solution to an electrostatic problem in a volume of capacitor paper consisting of cellulose and pores with air and water. First, the possible scenarios for the growth of breakdown in capacitor paper are analyzed and to the conclusion is made, that complete breakdown developed from a partial breakdown in the air cavity. A brand of capacitor paper is chosen in such a way that when its thickness changed, the breakdown strength of the electric field changed over a wide range. Then, for the paper with the lowest average electric field intensity the possibility of explaining the complete breakdown by the breakdown of air segments on the basis of the Paschen dependence is checked. Further points of the obtained dependence by constructing models of papers of the same brand and a different thickness under the assumption of the similarity of electrostatic fields are determined. As such a criterion, the constancy of the equivalent effective permittivity are taken. Results. The dependence of the breakdown strength of the air in the range of 1.36...5.54 μm under normal conditions is determined. The obtained relationship is between the Peschot and Taev curves. Originality. For the first time, the possibility of indirectly estimation the breakdown strength of an insulating material using an electrostatic field model is indicated. Practical value. The proposed method for the numerical calculation of the breakdown voltage of air inclusions in the presence of water inclusions in the thickness of solid insulation can be applied to other types of solid thin-layer insulation.

The article is devoted to the press coverage of the development of the educational process in Kyiv in the Central Rada period. The relevance of the study is conditioned by the lack of a comprehensive research of the educational environment in Kyiv in this period with the use of periodicals. The daily Kyiv editions «Nova Rada» and «Kyivlyanyn» have been used as a source base. Being different in terms of materials, methods of presenting information, style of writing and ideological orientation, these news papers covered different issues of education in the city. Qualitative and quantitative analysis, namely content analysis, which is a formalized method of interpreting texts, allows to increase the information content of such an inexhaustible source as the press. In the context of this research, the qualitative and quantitative analysis is useful to study advertising and reference sections of news papers, determined by the consistency and relative homogeneity of the content, with the goal of stating the frequency of indication. With the help of news paper publications, the changes that took place in Kyiv education have been revealed, the factors that influenced its democratization and Ukrainization have been clarified, and the challenges faced by participants in the educational process during 1917 and early 1918 have been identified. The possibility of reconstruction of everyday life of Kyiv students, schoolchildren and teachers with the help of periodicals has been proved. The impact of revolutionary changes on the Kyiv educational environment has been studied through the prism of everyday life, and their consequences for the functioning of educational institutions have been assessed. On the basis of advertisement on the pages of the press, the conditions of admission to higher and secondary schools, the specifics of education, the social and gender component of potential entrants, the introduction of mixed education have been determined.

The paper presents the research results on the properties of the pulp coniferous and deciduous wood composition in its original state and paper made from it, proposes a mechanism to increase the waterfast and waterproof food packaging paper by surface treatment with a composition based on polyamidepichlorohydrin with polyvinyl alcohol and urea. The study was conducted in order to ensure an increase in the consumer properties of packaging paper, since when packaging materials encounter food products, their structure can change under the influence of moisture, steam, and gas. Polyamidaminepichlorohydrin was used as the main component of the composition for paper processing, as functional additives: polyvinyl alcohol and urea. The above-mentioned starting materials are environmentally friendly, since foreign inclusions in food packaging materials would pose a serious danger to human health and life, as well as to the brand image of the product in which they would be detected. It was proved that high waterfastness and waterproofness, as well as the necessary level of barrier, protective and operational properties of packaging material for food products cannot always be obtained by introducing a significant amount of polyamidaminepichlorohydrin, so the paper investigated the mechanism of interacting cellulose fibers of paper with polyamidaminepichlorohydrin, and also proved the possibility of its use to obtain packaging paper with a given set of properties. It was found that the consumption of up to 4–6% polyamidaminepichlorohydrin provides the main increase in the mechanical strength of packaging paper, both in wet and dry conditions. The resulting waterfast and waterproof material can be used for food packaging.

Background. The development of technologies for obtaining materials from plant raw materials, the use of which improves the consumer properties of cardboard and paper products and does not pollute the environment with harmful substances from synthetic polymers, is an urgent problem of our time. Objective. The purpose of the paper is to obtain pulp and nanocellulose from reed stalks by environmentally friendly methods and apply nanocellulose to improve the quality parameters of paper for packaging food products on automatic machines. Methods. To obtain pulp from reed stalks with a minimum residual content of lignin and minerals, two processing stages were used: alkaline extraction and organosolv cooking at a temperature of 97 ± 2 °C. Nanocellulose was obtained by the oxidation of organosolv reed pulp with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) in the TEMPO / NaBr / NaClO system, which is more environmentally friendly than acid hydrolysis. The resulting nanocellulose was applied to paper samples from waste paper and sulphate unbleached pulp at a consumption from 1 to 3 g/m2. Results. Organosolv pulp was obtained from reed stalks with a residual lignin content of 0.53 % and an ash content of 0.045 %, which was used to obtain nanocellulose. The resulting nanocellulose particles have a transverse size in the range of 5–20 nm, a length of up to several micrometers, and the tensile strength of nanocellulose films is up to 60 MPa. It is shown that the application of nanocellulose to the surface of the samples increases the breaking strength and breaking length, and reduces the surface absorbency of paper. It was determined that with a nanocellulose consumption of up to 3 g/m2, paper samples have indicators that meet the requirements of the standard for paper for packaging food products on automatic machines. Conclusions. The use of nanocellulose from reed stalks as a hardening substance for paper production will allow replacing environmentally harmful polymer additives and up to 50 % of more expensive softwood pulp with waste paper, while maintaining paper quality indicators at the level of standard requirements.

In recent years, concrete in the construction industry has rapidly increased worldwide, including developing countries like India. The raw materials required to produce such a quantity require huge depletion of natural resources. On the other hand, disposal of paper waste, fly ash, and plastic waste is one of the biggest problems faced by many countries, including India, the amount of waste collected and recycled is less compared to disposal quantity. The use of these wastes in concrete reduces the disposal of waste in nature. In this experiment work, the use of these wastes in the concrete has been studied. Preliminary tests like specific gravity, fineness modulus, and water absorption have been carried out on the materials. Various mix designs are prepared by partial replacement of cement with fly ash and paper pulp, and sand is completely replaced with the quarry dust, and coarse aggregate is replaced with shredded plastic waste to create sustainable concrete. A comparative study on the properties like slump cone, the weight of the cubes, compressive strength and split tensile strength, and feasibility of such concrete has been carried out. Results indicated that the weight of cubes started to decrease with the addition of waste. Compressive strength and split tensile strength show that the strength started to fall with the addition of plastic. The cost of concrete decreased with the addition of waste. 5 % of plastic waste in concrete and 3 % of paper pulp, and 5 % of fly ash is considered the optimal replacement percentage.

One of the most energy-intensive processes is the drying process. Therefore, an important task is to reduce heat consumption for drying. Various ways to improve the drying devices of paper and cardboard machines are identified. The main disadvantages of these improvements are given. The limiting factor of heat transfer from water vapor to paper is established. The dependence of thermal resistance on the thickness of the condensate layer is given. The authors have developed a new design for condensate drainage. The developed design allows installing movable siphons without replacement of steam inlet heads of the old type (for fixed siphons) with their insignificant modernization and cutting of an annular groove inside the drying cylinder. This will ensure a minimum level of condensate and eliminate the possibility of suction of steam into the condensate return system. Additionally, this will reduce thermal resistance, heat loss, and reduce energy consumption for paper drying as a whole.

New Ukrainian and world realities set new tasks for the higher educational establishments, which are related to the search for new, modern methods that allow to increase the effectiveness of training. Currently, topical are the issues of not only professional but also the personal development of the student forming the priority in the implementation of educational activities in universities, preparation for future professional activities, as well as for successful interaction in society. The concept of «individual social competence» is an important factor in creating a system of educational process which takes into account aspects of professional development, and at the same time the peculiarities of the formation of the student personality. The author analyses the concept of «competence», considers the key competences for lifelong learning, identified by the European Parliament and the Council of the European Union, including social competence, studies the scientific achievements of Ukrainian and foreign scientists, including G. Gedviliene, H. S. Han, K. M. Kemple, U.P. Kanning, M. Horenburg, G.W. Ladd, H. K. Ma, K. Monahan, M. Monnier, O.V. Varetska, N.I. Hlebova, D.V. Hubareva, O.I. Hura, M.O. Doktorovych, I.B. Zarubinska, O.O. Subina, V.M. Shakhrai. They explored different aspects of social competence of different age categories. The author concludes that, despite different interpretations, all scientists agree that social competence is an acquired skill, it can be formed and developed throughout life. It was also determined that the developed social competence determines the status of the individual in society, it affects the success in professional activities. The high level of social competence allows a person not only to be realized in professional activities, but also to influence the processes in society, which in turn determines its stability. The author’s definition of the concept of «individual social competence» is given in the paper; the author concludes that social competence is an integrated ability that contains other competencies: spiritual, civic, communicative, linguistic; the concept of social competence is closely related to professional competence, without the successful interaction of the individual with society it is impossible to acquire the skills and abilities inherent in a qualified specialist. Thus, an important task for modern higher education is the formation and development of social competence of students, which is the key to successful implementation of the future specialist in professional activities. The educational process should be aimed at forming a system of knowledge about interaction in society, understanding the system of social values, ability to cooperate in society, the ability to communicate constructively, because only a socially competent person can.

Maintaining of the proper predetermined paper pulp consistency on the different stages of the paper or cardboard manufacturing process significantly affects on quality and self cost of manufactured articles. The improvement of precision and repeatability of the paper pulp viscosity and consistency measurements is relevant to paper industry. Objective of the work is to improve the industrial-type paper pulp rotational consistometer. A new method for measurement of paper pulp concentration by means of a rotational viscometer was suggested which enables determining the flow consistency index K and flow behavior index n in the Ostwald-de Waele power law. The influence of the following torques on the measurement results is eliminated thanks to the new method: the friction torque in the seal of the sensitive element, the friction torque in the bearings of the shaft and the torque created under the influence of the flow with distorted flow speed profile. This is achieved by measuring the torque which acts on the sensitive element approaching the selected frequencies of sensitive element rotation both from the lower and higher frequencies. The mean torque value is calculated based on the obtained values. The measurements are conducted for two sensitive element rotation frequencies adjusted in advance. The frequency of sensitive element rotation is changed by means of a frequency converter. It is shown that by using two different rotation frequencies of the sensitive element of a rotational viscometer it is possible to define the flow consistency index and the flow behavior index. Paper pulp viscosity and consistency is defined on the basis of these two indexes. It is also suggested to average the results of viscous friction torque measurement approaching the rotation frequency of the viscometer sensitive element to the working frequency chosen for measurement from the lower and higher frequency ranges. By averaging the results of such measurement the friction torques in sealing and bearings supporting the sensitive element shaft are compensated. By changing the rotation direction of the sensitive element and by further averaging the obtained results it is possible to eliminate the influence of the asymmetrical distribution of paper pulp flow speed in the pipeline. This improves accuracy of the paper pulp consistency measurement.

Background. Development of technology for obtaining peracetic pulp from oat straw and its use in the production of one of the paper mass types. Objective. Determination of peracetic cooking technological parameters’ optimal values for oat straw peracetic cellulose quality indicators. Methods. The oat straw cooking was carried out with peracetic acid at 95 ± 1 °C from 90 to 180 min for hydromodulus 8:1 and 7:1, using a sodium tungstate catalyst. To determine the oat straw peracetic cellulose mechanical indexes, laboratory samples of paper weighing 70 g/m2 were made. Results. Technological parameters’ optimum values (temperature, cooking duration, hydromodulus, hydrogen peroxide and acetic acid concentration) for the oat straw delignification process were established. It is shown that the sodium tungstate catalyst addition to the cooking solution at a rate of up to 1 % of the plant raw material weight helps to reduce the lignin content in cellulose to 15 %. A diagram of the cellulose yield dependence on its residual lignin content for various methods of non-wood plant material species delignification is constructed. The high efficiency of the peracetic method for obtaining cellulose from non-wood plant raw materials, in particular from oat straw, has been confirmed. It is determined that the obtained peracetic cellulose from oat straw has high mechanical indexes. Conclusions. Oat straw peracetic cellulose can be used for the production of paper and cardboard mass types, in particular wrapping paper.

In this work the peculiarities of reading comprehension from electronic, audio devices and hard copies were studied through comparative analysis of the learning accuracy and electrical activity of the brain when reading or listening to the text. Eighty students took part in the research. They were offered 2 passages of text from fiction and popular-scientific literature for reading, presented in a form of an e-book, MP3-format and in a printed copy. The level of comprehension and assimilation of the read material was checked by testing based on the content of the text immediately after reading and in 2 weeks. The comparative EEG analysis did not reveal significant differences in the spectral power of the studied ranges when reading a paper book and e-book. Differences were found when listening to audiobooks comparatively to reading. In general, the effectiveness of text learning does not depend on the way of its presentation, however, sex and individual traits of a person, such as preferred learning style and extraversion level, are more important.

In the paper, the historiography of the problem is examined. The critique of the privet paper money which was circulating in the Ukrainian lands in 1917–1921 is conducted. The characteristics of such critique are shown and its distinctions from the critique of the state paper money are identified. The external signs of the bonds’ obverse and reverse are analyzed. The heraldic, emblematic, iconographic, sphragistics, neographic, filigree, ornamental, chronological and metrological elements of the Ukrainian privet paper money appearance are investigated and the role of these features is identified. The emblems, seals, imprints, signatures, series, numbers, dates are pointed out to be the most informative signs of the privet paper money. So, in the article, the great significance of the sphragistics, neographic and chronological data is underlined. By means of the text analysis, the issuers of bonds are identified. The critique of the bonds’ external features also showed the reasons for emission, the emitters’ guarantees and the scale of the privet paper money circulation.

Lipoedema is a chronic progressive disorder of adipose tissue leading to an enlargement of lower extremities. It is considered to be rare; however, the prevalence of the disease is underestimated because it is commonly misdiagnosed as obesity or lymphedema and the general awareness is poor. The etiology of the disorder is considered to be multifarious, including genetic inheritance, hormonal imbalance and microcirculation alterations. Diagnosis is mainly based on medical history and physical examination. Management of lipoedema is focused on reducing the symptoms, improving the quality of life and preventing further progression of the disease. The aim of this paper is to raise the awareness of the disease and provide appropriate clinical guidance for the assessment of lipoedema. We searched through the PubMed/MEDLINE database and took into consideration all of the results available as of 6September, 2020 and outlined the current evidence regarding lipoedema epidemiology, etiology, clinical presentation, differential diagnosis, and management. Better understanding of lipoedema is crucial for establishing an early diagnosis and a proper treatment, which in turn will reduce the psychological and physical implications associated with the disease.

Oil extracted from mobile phone waste recharge scratch cards paper by thermal pyrolysis was investigated. The oil was characterized by its physical, chemical, and functional groups present. The physicochemical characteristics of the oil determined are density 900 kg/m3, viscosity 1.5 mm2s-1, acid value 1.122 mgKOH/g, saponification value 98.175 mgKOH/g and iodine value 22.84 gI2 /100g. The pour point and flashpoints are -15 °C and 90 °C respectively. The Fourier Transform Infrared (FTIR) and Gas Chromatography-Mass Spectroscopy (GC-MS) revealed the presence of aldehydes, ketones, carboxylic acids, esters, alkenes alkanes, ethers, and phenol. This indicates that the oil has industrial applications in chemical, pharmaceutical, and biodiesel production.

A visual test method has been proposed for the evaluation of the gold content. It is based on the linear dependence between the length of the colored zone on an indicator paper and gold(III) concentration. Indicator paper was covered by a polymer film and was in contact with the solution tested along one edge during analysis. It was impregnated by 3-phenyl-2,6-dimercapto-1,4-thiopyrone or by precipitate of its complex with copper(II). Besides Cu(II) can be replaced by the Au(III) ion tested in the composition of this complex. The concentration ranges for Au(III) determination were equal to 0.02−2 mg·L−1 or 4−590 mg·L−1, respectively, in the presence of excess of the transition and noble metals. It was demonstrated the effectiveness of the dynamic preconcentration of Au(III) for the subsequent colorimetric determination on paper filter for the concentration range 0.005–0.3 mg·L−1 (DL 0.02 mg·L−1) by using a sample volume of 10 mL. The developed procedures were successfully utilized for the determination of gold in synthetic mixtures, in auriferous quartz (RSD < 5%), and in ore from Zyryanovsk’s mine (Kazakhstan) with RSD < 8%.

Introduction. An important problem in power transformers resource prognosis is the formation of moisture dynamics trends of transformer insulation. Purpose. Increasing the accuracy of power transformer insulation resource assessment based on accounting of moisture dynamics in interrelation with temperature dynamics. Working out of moisture dynamics model in paper insulation-transformer oil system in conjunction with thermodynamic model, load model and technical maintenance model. Methodology. The mathematical models used for describe the moisture dynamics are grounded on nonlinear differential equations. Interrelation moisture dynamics model with thermodynamic, load and technical maintenance models described by UML model. For confirming the adequacy of model used computer simulation. Results. We have implemented the model of moisture dynamics in power transformers insulation in interrelation with other models, which describe the state of power transformer in operation. The proposed model allows us to form detailed trends of moisture dynamics in power transformers insulation basing on monitoring data or power transformers operational factors simulation results. We have performed computer simulation of moisture exchange processes and calculation of transformer insulation resource for different moisture trends. Originality. The offered model takes into account moisture dynamics in power transformers insulation under the influence of changes of the power transformers thermal mode and operational factors. Practical value. The offered model can be used in power transformers monitoring systems for automation of resource assessment of oil-immersed power transformers paper insulation at different phase of lifecycle. Model also can be used for assessment of projected economic efficiency of power transformers exploitation in projected operating conditions.