bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of the influence of 3D printing modes with ceramics and sintering on the shrinkage process of thin-walled models
Authors: Piterskov P , Egorov S , Boyko E , Grigoriev M 
Published: May 2020

Abstract
The subject of this study focuses on the effect of 3D printing and heat treatment of thin-walled models made of ceramic paste. The plates with dimensions of 20*5*40 mm were used as the models. The methodology includes the creation of ceramic objects using 3D printing by the SLA method (stereolithography) and their further heat treatment. The surface quality and the shrinkage percentage of samples printed in different modes and thermally processed under different conditions are compared. It was found that with a decrease in layer thickness and particle size, as well as an increase in the duration of heat treatment, the surface quality of the samples improves and the percentage of shrinkage decreases approximately 2 times. Using new modes and improved heat treatment conditions, samples with the least number of cracks and a lower percentage of shrinkage were obtained, which allows using this process to create ceramic products of higher quality. The method of creating ceramic products used in the work in the future can be applied in such industries as aircraft manufacturing, medicine, biotechnology and other fields.
Regulation of powder particle sizes during plasma spraying
Authors: Ermakov B S , Ermakov S B , Pavlenko A , Vologzhanina S A 
Published: May 2020

Abstract
One of the factors constraining the development of 3D technologies is the shortage of powders for additive machines. St. Petersburg Polytechnic University (SPbPU) is developing the design and production of plasma nozzles to produce metal powders and alloys intended for additive machines. The article discusses the results of studies of the effect of pressure powders and flow rate generated in the spray chamber in the production of powders from 08Cr18Ni10Ti and CrNi60BWoTi alloys on the particle size distribution.
Features of the use of light alloys in the marine climate of the arctic zone
Authors: Ermakov S B , Ermakov B S , Andreev A K 
Published: May 2020

Abstract
The movement of mining and processing industries to the North poses the task of analyzing the performance of materials traditionally used in structures and products. The paper presents the results of comparative studies of magnesium alloy MA2-1 and aluminum alloy AMg6 in the marine climate of Northern latitudes. The studies were carried out after simulating the long-term operation and storage of alloys in northern latitudes, namely after long 1000-hour exposures at a temperature of -600 ° C, aging in a salt fog chamber. We analysed the impact of external climatic factors, typical of northern latitudes, on the mechanical properties and a comparative assessment of the corrosion resistance of alloys in a marine climate.
Lanthanide doping of AIIIBV crystals
Authors: Romanov V V , Ermakov B S , Kozhevnikov V A , Stelmakh K F , Vologzhanina S A 
Published: May 2020

Abstract
The state of rare earth impurities at concentrations of about 1018 cm−3 in volume-doped AIIIBV semiconductor crystals can be described in the framework of the model of quasi-molecular rare earth centers of Ln2O3 type and spontaneous polarization regions-coupled spin-polarons localized on small donors.
Specificities of control over multifactorial objects in food production
Authors: Balyubash V A , Alyoshichev S E , Pashkova E A , Ivanov V L 
Published: May 2020

Abstract
The research deals with control methods of multifactorial objects of food production, representing diverse technological processes occurring in continuous, discrete-continuous and discrete modes. This is especially relevant for systems in food production having the series connection of technological units, separated by apparatus-technological capacities and resistances. For such units, a transient delay value is significantly greater than that of single-capacity objects. A solution proposed: the use of two-loop automatic control systems capable of improving system quality parameters in facilities of chemical and technological processes. The two-loop automatic control system is relevant when the object is subjected to frequent disturbing influences from the regulator and has a low inertia parameter. The internal control loop suppresses arising internal disturbance caused by the specifics of the process itself, and the external loop is responsive to disturbing influences coming from outside, e.g., with changing properties of the incoming raw materials.
Strength of structural elements with cracks
Authors: Peregudov A A , Vologzhanina S A , Igolkin A F 
Published: May 2020

Abstract
In almost every detail, despite careful control at all stages of production, there may be cracks. The reasons for their occurrence can be very different, including the shape and size of the part, the conditions and nature of loading, the nature of the environment, defects of a crystal lattice, the possible presence of non-metallic inclusions adverse forms, structure and grain size, depending on the technology upstream processing, fatigue, etc. The reliability of the equipment is determined by the correct choice of material and taking into account the operating conditions, including the level and nature of loading. The paper provides a comparative review of the main approaches for selecting strength criteria for structural elements with cracks. The energy and power strength criteria are considered. The energy criterion of A. A. Griffiths considered a perfectly brittle material without taking into account the plasticity reserve of real metal materials. The force criterion allows us to estimate the value of the stress taking into account the critical moment of loading, at which unstable destruction begins due to the reserve of elastic energy. It is shown that the transition of steel from a plastic state to a brittle one is influenced by the test temperature, the type and speed of deformation, and changes in the chemical composition and mode of heat treatment. Thus, when choosing a certain strength criterion, you should take into account the operating conditions and the degree of responsibility of the structure.
Numerical analysis of the heat flux density of the whole-body cryotherapy (WBC) object coming from the skin
Authors: Yerezhep D , Minikaev A , Zhignovskaia D , Pronin V , Yerezhep A 
Published: May 2020

Abstract
In technologies of cryotherapeutic effects, the main attention is paid to the choice of temperature of cryogenic gas. At the same time, along with the gas temperature, other process parameters are also essential: the gas velocity, the dimensions and spatial orientation of the biological cooling object, the humidity and gas velocity, etc. To develop the technique and technology of general cryotherapy, generalizing research is needed that can form the theoretical basis for the production and design of cryotherapy equipment. The most general results can be obtained by studying the effect that cooling has on a biological object with different intensities of heat removal along the length of the biological object. The work will conduct a chilled analysis of heat flux losses from the surface of the skin of a biological object with a slight change in the geometry of cryosauna during the whole-body cryotherapy process (WBC). To implement these tasks, a software package using the finite element method will be used. To describe the biological object with internal heat release, these biological heat equations were solved using the Penns approximation. The results of this work will help to give recommendations to cryosauna manufacturers to optimize the design of the cryotherapy unit, which in turn will help to increase the effectiveness of cryotherapy.
Power interactions of scroll compressor elements
Authors: Minikaev A , Yerezhep D , Zhignovskaia D , Pronin V , Kovanov A 
Published: May 2020

Abstract
The subject of our research is a scroll compressor. With its large number of advantages over reciprocating compressors in the form of overall, mass and production characteristics, they have their own difficulties associated with the theory of stability of a movable scroll during the operation process. As you know, a complex system of forces acts on the spiral, is very variable in magnitude and direction, for the period of one orbital revolution of the spiral. It should be noted that in modern designs of scroll compressors in the axial direction, a movable scroll has most often a one-sided rigid support - a thrust bearing. Moving the movable spiral in the opposite direction is limited only by the force of the gas axial pressure, which does not guarantee it saving its original position, at least within the gaps, touching the movable and stationary spirals, which is unacceptable. Next, we consider the basic calculation equations associated with the stability of a moving spiral.
Innovative online technologies as a tool of qualified specialists training in the field of waste management
Authors: Kakabayev A A , Fakhrudenova I B , Kurmanbayeva A S , Yevloyeva A S , Saparbekova A A 
Published: May 2020

Abstract
The article discusses new technologies that are used in creating content for online training modules, as well as specific examples of using certain tools in the formation of courses for online modules in the field of waste management in the framework of the EduEnvi project. The article describes online tools that can be used for visualizing, structuring and systematizing of various types of information, such as describing the course structure, showing a list of topics, possible tasks, etc. The need for visualization and systematization of information becomes very important when it comes to online training, which requires developers to be an extremely clear and detailed presenting their educational material, teaches them to be more open and communicative. The article also contains information about the formats of work in the project which helps partners from five different countries to exchange experience, learn something new and develop online courses. These online courses will be the main result of the EduEnvi project.
Study of submicrocapsules structure stabilized by modified silica dioxide nanoparticles
Authors: Zh Mutaliyeva B , Tleuova A B , Madybekova G M , Kurmanbayeva A S 
Published: May 2020

Abstract
In this research the structures of Miglyol 812 submicrocapsules, stabilized by silica dioxide nanoparticles, modified by oleic acid, were studied. It was found that the size distribution of silica particles modified with oleic acid depends on the amount of oleic acid. There is a limit to the ratio of oleic acid to silica at modification of silica particles with oleic acid. Experimental results have shown that the optimal ratio of oleic acid to silica is in the range from 110−2 to 5 10−1. The use of silica particles modified with oleic acid allows to obtain an emulsion with a 30 % of oil phase, with an average size from 80-300 nm. Thus, modification of hydrophilic silica particles with surfactants such as oleic acid in order to make them more hydrophilic and able to be adsorbed at the oil / water interface can be used to prepare a stable Pickering emulsion. As a result the stable Pickering emulsions which can be used for encapsulation of various substances were obtained, and the use of microcapsules allows one to decrease their impact on environment and increase efficiency of usage.
Perspective of using the biological method for gaseous emissions cleaning in the food productions
Authors: Nazarova A V , Kurnikova N V , Molodkina N R , Yulmetova R F , Sergienko O I 
Published: May 2020

Abstract
The article considers the problem of contamination of exhaust gases of confectionery plant because of harmful substances and unpleasant odors. A confectionery production uses a wide range of aromatic substances. Moreover, despite the presence of operating air treatment facilities the specific smell of ambient air could be sensed. To identify the most powerful sources of odor emissions the organoleptic study was conducted. Also, with the help of olfactometric study of the sources of odor, the composition of the aromatic mixture with a predominant content of terpenes and benzaldehyde was revealed. Several methods of treatment of gases-air emissions were studied including biological, thermal and thermocatalytic. Among the biological ways of air treatment, three types have been considered: traditional biofilters, trickling biofilters and bio scrubbers. Bacteria that helps to decompose aromatic substances like benzaldehyde or some of the terpene series have been found. Additionally, the mechanism of transformation of odorous substances has been studied.
Study of the content of heavy metals in the berries of the Vaccinium genus in the background areas of the North-West of Russia
Authors: Dinkelaker N V , Semenova T S , Ulyanov N B , Didikov A E , Petrova O V , Moiseenko E N , Dinkelaker N F J , Sinelnikova N A 
Published: May 2020

Abstract
The study of heavy metal contamination of products of wild berries of the genus Vaccinium (blueberry, cowberry, cranberry), growing in intact forests in four regions of North-West Russia-Leningrad, Pskov, Novgorod and Vologda regions is carried out. It is established that the greatest accumulation in berries of all studied species is observed for zinc, chromium and manganese. At the same time, the excess of the maximum permissible concentrations was noted for other metals - lead and arsenic, the level of pollution was moderate. In relation to these pollutants, the most sensitive genus is cranberry. The most likely source is roads and logging activities. The obtained results indicate the need to control chemical contamination of food products of wild berries and to expand the range of controlled parameters, in particular, the establishment of maximum permissible concentrations for chromium and nickel due to their significant bioaccumulation in berries.
Extreme vibration increase of the heat transfer coefficient of short heat pipes
Authors: Seryakov AV , Konkin AV 
Published: May 2020

Abstract
The results of the heat transfer coefficient studies of the short linear heat pipes (HP’s) with a formed by the capillary-porous insert vapour channel in the Laval nozzle-liked form under high thermal loads and external vibrations are presented. Under high heat power loads the vaporization process in the capillary-porous evaporator and vapour propagation in the vapour channel acquires a pulsating character with a frequency of 400-500 Hz and the amplitude up to 103 Pa. For the first time it was experimentally detected that under external longitudinal vibration, attached to the HP’s body with an limited amplitude of 0.15 mm and frequency equal to the frequency of arising internal vapour pulsations, the HP’s heat transfer coefficient shows the resonance nature and increases by up to 20%. The increase in the heat transfer coefficient is due to the boiling process intensification in the grid HP’s capillary-porous evaporator.
Development of a fast method for forming Braille on the surface of steels with IR ns-pulsed 50 W fiber laser
Authors: Amiaga J V , Vologzhanina S A , Ermakov B S , Gorny S G 
Published: May 2020

Abstract
Convex linear structures of various configurations with a height of up to 200 microns and a depth of up to 100 microns, point structures with a height of up to 500 microns were obtained on the surface of the steel using a 50 W 1.064 μm wavelength fiber laser source. No additives were used. The structures were formed from the material of the irradiated steel by controlling the dynamics of the melt. The possibility of forming Braille on a steel surface using this technology is demonstrated. The results are encouraging for a number of industry sectors where electron beam machines and high-powered laser sources are cost prohibitive, and one need a high rate of obtaining relief.
Technological approaches to the quality management of bakery products
Authors: Fedotov V A 
Published: May 2020

Abstract
The article studies the influence of the physicochemical properties of wheat grain on the quality indicators of bakery products. Methodological approaches to managing the quality of bakery products through the development of production solutions have been formed by varying the technological parameters of the use of wheat flour (moisture of the leaven when the leaven method of dough preparation is used) taking into account its physicochemical properties (hardness of wheat grain). Wheat grain in a wide range of hardness - from low-hard to ultra-high-hard was studied. Regulated indicators of bread quality were the volume yield of bread and the integral characteristic of the organoleptic evaluation of bread on a 100-point scale. It is shown that the increase of grain hardness of flour and gain in moisture of starter dough (the average yield by weight of bread increases by 1% when the moisture of starter dough is 8 %) lead to increasing bread’s yield by weight. To simplify the model of forming the quality of bread depending on the grain hardness and humidity of the used starter dough, a constant value of the specific work when dough kneading was used. Regression equations for the formation of white bread quality indicators with a high degree of confidence (determination coefficient 0.72-0.89) and corresponding bread quality nomograms are constructed.
Comparative analysis of elasticity and rigidity of morphological parts of wheat grain
Authors: Fedotov V A , Yu Solovykh S 
Published: May 2020

Abstract
The article presents the results of a comparative assessment of the elasticity and rigidity of various morphological elements of wheat grain depending on the nature of the grain (normal, frosted, after drying, after scouring machines). The dependences of the rigidity of wheat grain on the structure, chemical composition and humidity are described. A close correlation was revealed between the structural and mechanical properties of wheat, assessed by microhardness, strength index, and the results of laboratory and industrial grinding of wheat grains of various consistencies. For different consistency of wheat grain, microhardness was determined using the microhardometer “Miniload”, and the strength index was determined using the Brabender’s hardness tester. At relatively low stresses, the shells have flexural elasticity. IT was detected that with increasing humidity, the rigidity of the shells during bending decreases. It was found that for hard and hard-grained varieties of soft wheat, the compression force is required 2-4 times more than for soft-grained varieties. It is shown that the microhardness of glassy grains of hard-grained and soft-grained wheat varieties is basically at the same level. At the same time, with increasing humidity, the microhardness of the grain decreases regardless of the variety, area of growth and vitrescence of wheat.
Thermodynamic cycle of lithium bromide absorption chillers with two-level absorption and generation processes and with associated mass flow
Authors: Malinina O S , Kasyanov A V , Baranenko A V 
Published: May 2020

Abstract
The paper presents the assessment of the energy efficiency of the thermodynamic cycle of the absorption lithium bromide refrigeration unit with two-level absorption and generation processes with the associated mass flow. The analysis of temperature effect of heating and cooling sources on thermal coefficient is carried out. The parameters of external sources when it is possible to determine the energy efficiency of the thermodynamic cycle are defined.
Calculation of cold accumulators with phase change materials
Authors: Yu Zakharova V , Kuznetsov P A , Baranenko A V , Faizullin R O 
Published: May 2020

Abstract
The paper presents an improved technique (mathematical model) for numerical calculations of solid-liquid phase transitions based on a zero-dimensional solution of the Stefan problem for cases of placing phase change materials in ball-shaped or cylindrical capsules. According to the proposed model, numerical calculations of the liquid phase volume fraction in Scilab have good compliance with experimental data for n-octadecane, and the calculation time is reduced several hundred-fold in comparison with calculations in Fluent.
Results of temperature effect on thermo-physical properties of guava fruit of Southeast Asia
Authors: Tun A , Baranov I V , Krylov V A , Tambulatova E V 
Published: May 2020

Abstract
The research presents the results of the effect of temperature on thermo-physical properties of guava fruit of Southeast Asia. Guava is an energetic fruit with high nutritional value and is considered a tropical fruit of South-east Asia. Fruit growers need to use cold storage facilities to extend the revenue period while maintaining produce quality and freshness. The storage life of fresh fruits can be extended by several days by cooling. The specific heat of foods can be used to calculate the refrigeration load calculation. Therefore, the specific heat of food plays an important role in the design of storage and transport systems. One of the most important thermo-physical properties in foods are specific heat. The authors of the article used differential scanning calorimetry (DSC 204 F1), by which the specific heat of guava fruit was determined in the temperature range from –25 to 25 °C. It was found that the specific heat of guava fruit is dependent on temperature.
Performance of FRC and GPC for High-Rise Construction: Case Studies
Authors: Gharehbaghi Koorosh , Rahmani Farshid , Paterno David , Gharehbaghi Sara 
Published: May 2020

Abstract
This paper aims to compare Fiber Reinforced Concrete (FRC) and Geo-Polymer Concrete (GPC) for high-rise construction. In doing so, 8 case studies from the USA and Australia are reviewed. The ever-increasing use of material processing linked to environmental degradation has encouraged industries to seek alternative materials. Both FRC and GPC are examples of such alternative materials. Their composition of these materials is derived from manufacturing, building and construction excess. Concerns remain, however, regarding these material’s abilities such as strength, when compared to the traditional i.e. concrete, steel etc. This paper reviews select case studies where FRC and GPC materials have been used. In addition, their overall structural integrity was also observed. This paper then scrutinized their Structural Health Monitoring (SHM) to uncover their specific structural performance. Subsequently, this paper found that for both FRC and GPC extreme weathering conditions may affect their structural performance. Finally, case study review also indicates additional comprehensive research is required to review such relationship.