bluuebunny/crossref_metadata_2025 huggingface dataset:
Teaching BPS to architects: A closer look at the building performance simulation ‘consumer’ and ‘performer’ training paradigms
Authors: Alsaadani S , Bleil De Souza C
Published: December 2019

This contribution builds upon a previous study, in which three university-level BPS training paradigms were identified. Using a critical literature review, we focus on two of these; training the ‘consumer’ and ‘performer’ architect, exploring similarities and differences between teaching approaches of these two paradigms. Divergences are found in the location of BPS teaching content within the wider scope of architectural program delivery. The ‘consumer’ paradigm is generally followed in undergraduate architectural education, tends to be taught as an elective module and is almost always linked to a design studio component. The ‘performer’ paradigm is linked to both undergraduate and postgraduate architectural education, is mostly affixed to stand-alone core technical modules and is sometimes attached to the design studio. Similar BPS performance domains are taught across both paradigms, but the rationale underlying BPS tool selection differs. Visualization capabilities and ease-of-learning tend to be the criteria used to justify selection of BPS tools used in articles describing the ‘performer’ paradigm. On the other hand, assignment of BPS tasks to an ‘expert’ under the ‘consumer’ paradigm allows for software with more complex analytical functions to be selected. To conclude, the findings demonstrate how moving beyond descriptions of individualized teaching experimentations in BPS research, toward cross-paradigmatic studies of BPS education, many contribute to the construction of a much-needed foundation to support BPS teaching in the future.
A framework for generating thermal performance envelope
Authors: Talaat Hazem , ElMasry Ayman
Published: December 2019

Throughout the last decade, environmental topics in architecture start to gain interest to preserve natural resources, and to improve the performance of designs. One of the great problems facing architects, is checking whether their designs compromise with the environmental needs or not. Thermal performance is one of the main issues related to environmental design. This research proposes a framework for thermal design of envelopes, by simulation and optimization of building envelopes based on computer algorithms and environmental simulation programs. Through analytical methodology, main optimization algorithms and thermal design parameters are analyzed to achieve the framework. It explains the essential concepts of computer programming, and how it is integrated into the architectural design process to achieve thermally efficient envelope. Designer is introduced to computer programming from a theoretical point of view, with an explanation of the types of input needed by the algorithms. In order to achieve this, different types of algorithms and their output, how to define the optimization problem and its variables, the different types of 3D virtual modelling and environmental simulation programs and their role in the process, are discussed. The framework can be summarized in the following steps: building envelope analysis in terms of geometry and its categorization, determining the thermal criteria and target performance, modelling and simulation of the building envelope, and finally applying algorithm and optimization of the envelope’s thermal performance.
Investigation on utilizing garbage as a resource for a sustainable neighbourhood: Case study of a neighbourhood in New Cairo, Egypt
Authors: Guirguis Marianne Nabil , Moussa Rania Rushdy
Published: December 2019

Waste management comprises the actions required for managing waste material produced from human activities from its source of origin to its final removal. Usually, it collects resources from all forms of matter such as gaseous, liquid, solid, and radioactive. This action is made to avoid the negative effects of wastes on the environment and human wellbeing. The effect of accumulating waste may be highly severe for numerous communities in developing countries such as Egypt. Egyptian neighbourhoods suffer from effects of accumulating local wastes and garbage. Public health and the visual image of the neighbourhoods, in addition to the different social, economic, and environmental aspects of life are also harmed. In Egypt, this issue becomes more challenging because the defined policies for waste managementare yet in their dawn stage and hence, results are not yet as anticipated, which inflicts severe environmental hazards on Egyptian communities and drains a large portion of the local economy. This study aims to propose a technique to manage the organic waste in Egypt by storing them in anaerobic digesters which turns the wastes into electricity and biogas. It will focus on investigating current social and environmental aspects of the neighbourhood, to determine if this proposal will be appropriate as a solution for getting rid of organic wastes and generate energy, in order to create sustainable neighbourhood. A questionnaire took place revealing that using anaerobic digesters will help the Egyptian government in solve one of its major challenges which is getting rid of neighbourhood’s wastes which decreasing the level of pollutions and epidemics especially in low income districts.
Piezoelectric Tiles Is a Sustainable Approach for Designing Interior Spaces and Creating Self-Sustain Projects.
Authors: Solban Madonna Makram , Moussa Rania Rushdy
Published: December 2019

These days, the third worlds countries such as Egypt are facing a hug challenge toward energy production. Energy crisis is the most critical issue facing these developing countries. In the recent couple of years Egypt has experienced a serious shortage in the power supply which affect negatively the industry sector as well as the residential sector due to the shortage of natural gas production and fossil fuel which prevented the government from providing the basic needs of Energy to the community. Moreover, it affects negatively the developing of this country and building a new mega projects. Renewable energy sources can be an extraordinary method to tackle the energy issue in Egypt, the increasing of energy costs and decreasing of fissile fuel production helps in decreasing the gap between the cost of generating Energy from renewables and fissile fuel. It is important to set up public Egyptian facilities based on renewable energy as metro stations instead of relying upon fossil fuel as a main source of power. Generating electricity from piezoelectric cells to power metro station is a sustainable solution for the environment, economy, and social needs. Using piezoelectric cells in high density projects helps in creating energy self-sustain projects, people will start to produce energy from walking throughout the facility. The aim of this research is to highlight the importance of replacing ceramic and granite tiles with sustainable piezoelectric tiles, which will create a self-sustain project by redesign an interior space of public facilities. Designing the flooring tiles that integrate piezoelectric cells produce a useful amount of energy for electrifying public facilities using the visitor’s high population density. The research started to analyses projects that replaced regular tiles with piezoelectric tiles to understand the objectives and constrains of using this sustainable building material in Egyptian public facilities.
Synthesis of cross-linked polyurethane with self-healing properties
Authors: Platonova E O , Vlasov E , Kireynov A , Polezhaev A V
Published: December 2019

Prepolymer synthesized from toluene-2,4-diisocyanate (TDI) (hard segment), and polypropylene glycol (PPG-2000) (soft segment) was end-capped with difurfurylamine groups. A new cross-linked self-healing polyurethane was obtained via Diels-Alder reaction of the en-capped prepolymer with N,N’-bismaleimido-4,4’-diphenylmethane (BMI). Thermal reversibility of the Diels-Alder reaction (DA-reaction) between terminal furanic rings of the polyurethane prepolymer and bismaleimide cross-linking agent designed to be responsible for self-healing. Polymers were characterized by NMR and IR spectroscopy and thermal analysis (DSC and TGA). Thermal reversibility of the DA-bonds in the cross-linked polymer was confirmed by DSC. The synthesized polymer has good processability and potential recyclability.
Modeling of the effective universal constitutive relations for elastic laminated composites with finite strains
Authors: Dimitrienko Yu I , Karimov S B , Kolzhanova D Yu
Published: December 2019

The article considers the modeling results of layered composites with finite strains deformation according to the individual layers characteristics. The article proposes an asymptotic averaging method version for layered composites with finite deformations and periodic structure. The method allows calculating the effective deformation diagrams connecting the averaged Piola-Kirchhoff stress tensors components and the strain gradient.
Computational modeling of the conjugated thermomechanical and aerogasdynamics processes for composite structures of high speed vehicles
Authors: Dimitrienko Yu , Zakharov A , Koryakov M
Published: December 2019

A conjugated problem statement for aerodynamics and thermomechanics of heat-shielding structures from thermally decomposing polymer composite materials is proposed. It is based on the iterative solution of the three types of detached problems: aerogasdynamics problem for viscous heat-conducting flows, internal heat and mass transfer and thermoelasticity of shell constructions. An example of the numerical solution of the conjugated problem is given. It is shown that due to the high temperatures of the aerodynamic heating of the structure made of a polymer composite material there can appear a polymer phase thermodecomposition and intensive internal gas generation into the structure of the material.
Modeling of thermal stresses in inorganic matrix composite plates based on the asymptotic theory
Authors: Dimitrienko Yu I , Sborschikov S V , Egoleva E S , Yakovlev D O
Published: December 2019

A mathematical model has been developed for calculating a temperature non-stationary field and thermal stresses in thin multilayer plates of fabric composite materials on an inorganic matrix based on an alum-chromophosphate binder. The model allows to take into account changes in the microstructure in the matrix and composite fibers during high- temperature heating, taking into account the physical and chemical transformations occurring in them, as well as to calculate thermal stresses in thin plates from the tissue inorganic composite taking into account the kinetics of changes in the characteristics of composites during heating. Methods of multiscale homogenization and finite element modeling of microstresses in periodic cells were used to calculate the characteristics of the inorganic composite, and the method of asymptotic averaging was used to calculate the stresses in the plates. Some results of numerical simulation of the change in stresses in the composite plate during heating are given
On the Modeling of Thin Bodies of Revolution
Authors: Nikabadze M U , Bogatyrev M A , Ulukhanyan A R
Published: December 2019

The new parametrization of the three-dimensional thin domain of an arbitrary body of rotation is considered, consisting in using several base surfaces in contrast to the classical approaches. The vector parametric equation is given. The geometric characteristics inherent to the new parameterization are determined. Expressions for the translation components of the unit tensor of the second rank and also relations connecting different bases and geometric characteristic generated by them are written. The determination of the moment of an arbitrary function is given. The motion equations and CR of the micropolar theory of elastic rotation bodies without a symmetry center of variable thickness are obtained under the new parametrization, from which equations are obtained for very thin and shallow rotation bodies, both variable and constant thickness. The equations of motion and CR of any approximation in the moments of unknown functions with respect to an arbitrary system of orthogonal polynomials and, in particular, for the system of Legendre polynomials are derived. The questions of setting initial-boundary problems are discussed.
Selection of composite material composition for non-evaporable getters of new generation
Authors: Aleksandrova M V , Nikolyukin Y V , Kurganova Y A
Published: December 2019

The article is devoted to the issue of synthesizing materials of non-evaporable getters of the new generation with enhanced operational properties. The promising compositions of getter materials are considered, their basic properties are analyzed, and parameters that have a significant effect on their size are selected. According to the results of the literature analysis and patent search, a strategy was developed, on the basis of which three experimental compositions of the material for the non-evaporable getter were determined on the basis of the Ti-Zr system, a visualization-calculation model of the structure was constructed. Based on the traditional technology, the technology for the final product was developed. The results of studies of experimental samples of the material selected composition are presented and the level of acquired operational properties is predicted.
High density polyethylene modified with cyclohexyl dichloro-phosphonate
Authors: Shaov A Kh , Kharaev A M , Borukaev T A , Borodulin A S , Kalinnikov A N
Published: December 2019

A chemical modification of high-density polyethylene with cyclohexylphosphonic acid dichloride was performed during high-temperature extrusion. The physicomechanical properties and thermal stability of the modified polyethylene were studied.
Evaluation of the effectiveness of the introduction of a discrete filler in the aluminum matrix melt
Authors: Kurganova Yu A , Chen Yijin , Shcherbakov S P
Published: December 2019

Experimental samples of metallic composite materials filled with discrete Al2O3 fibers with a diameter of 10–20 nm were obtained by liquid-phase mechanical mixing. A technology has been developed for the effective introduction of a discrete filler into an aluminum melt, which ensures the absorption of the filler by the matrix. Device for the introduction of the filler was designed and manufactured. Recommendations were given on the choice of the composition and technological regimes for the introduction of a light discrete component of a composite material for sufficient assimilation by its matrix and ensuring the homogeneity of the structure. The structure and properties of the obtained samples of the new material have been studied. The changes made by the introduction of the selected nanodiscrete filler into the aluminum melt and the changes made by additional technological methods are analyzed. The effect of introducing discrete Al2O3 fibers into an aluminum melt was demonstrated.
Electric treatment of alumina composite materials
Authors: Minenko G N , Timchenko S L
Published: December 2019

A method of processing alumina composite materials using electric current is presented. Aluminum matrix composites based on aluminum alloy AK12 were obtained in a pass-through vessel with the addition of composite particles to the stream of molten material without the influence of an electric current and with the influence of a current. As a composite additive, graphite enriched with crystalline grade TG-1 and particles of titanium carbide (TiC) were used, the amount of the components being injected was 15 volume percent.

Measurements of the mechanical properties of the original AK12 alloy and composite material based on the AK12 alloy with the addition of composite particles carried out without an electric field and with exposure showed that the greatest increase in strength properties of alloys treated with an electric field was recorded for an aluminum matrix composite material with TiC particles, which amounted to 20% for ultimate strength and 24.5% for hardness. An increase in ductility was found in a composite material with a TG-1 composite additive, for it an increase in the relative elongation was 15.6%, while the electric current treatment of the composite material with a filler in the form of TiC did not lead to a change in the relative elongation of the sample material. In general, the increase in the strength properties of an aluminum matrix composite material with titanium carbide particles (TiC), after it was treated with an electric current, turned out to be slightly larger than that of an aluminum matrix composite material with particles of TG-1 enriched crystalline graphite. The physical mechanism of the influence of electric current on the properties of ALCM is given.
Influence of refractory nanosized particles of tungsten carbide and titanium on the structure and properties of the weld metal
Authors: Pankratov A S , Kobernik N V , Samokhin A V
Published: December 2019

The paper considers the influence of nanosized particles of tungsten and titanium carbides on the structure and properties of the weld metal of welded joints made by automatic submerged-arc automatic arc welding. To add them into the weld pool, an alloying composition was used in the form of composite granules based on nickel powder (PNE-1 as per GOST 9722). The prospects of using nanosized tungsten carbide particles for modifying the weld metal with the aim to increase the values of impact strength were shown. However, titanium carbide in the same conditions leads to a decrease in the average value of impact strength, despite the modifying effect of its use.
Application of a New Method of Non-Adhesion Defect Simulation in Multilayer Honeycomb Structures from Polymer Composite Materials for Various Nondestructive Testing Methods
Authors: Rusakov D , Chernushin V
Published: December 2019

A new method of non-adhesion defect simulation in multilayer honeycomb structures from polymer composite materials is discussed. This simulation method is particularly relevant for honeycomb structures with large cells. An experimental model for the comparison of two simulation methods, a new one and flat-bottom hole simulation, was fabricated. Advantages and features of application of the new simulation method for the nondestructive testing methods such as impedance, free oscillation, and through-transmission ultrasonic and thermal methods are shown.
Study of thermal expansion anomalies of multilayer steel materials at high temperatures
Authors: Kabantseva V E , Safonov M D , Plokhikh A I
Published: December 2019

The paper presents the results of a study of the anisotropy of the thermal coefficient of linear expansion (CTE), which was found in a multilayer metallic material based on steels, made by hot batch rolling. It is established that the material consisting of alternating layers of steel, has abnormally low CTE values in the direction perpendicular to the rental plane. To explain this phenomenon, a hypothesis was proposed about the relationship between normal and tangential stresses arising at the interlayer boundaries of such material. The confirmation of the hypothesis of the leading role of reactive stresses in the manifestation of the specified invar effect are the results of metallographic analysis. It is also shown that the conduct of cyclic high-temperature heating provokes recrystallization at the interlayer boundaries caused by the difference in the thermal expansion coefficient values of the adjacent layers and the effect of high temperature.
Polymer composites based on halogen-containing oligoethers
Authors: Bazheva R Ch , Borodulin A S , Kalinnikov A N , Charaev A M
Published: December 2019

Halogen-containing oligosulfones based on 1,1-dichloro-2,2-di (4-hydroxyphenyl) ethylene and 4,4’-dichlorodiphenylsulfone on various degrees of condensation were synthesized in the solution by high-temperature polycondensation. Conducted a physical modification of indutrial polycarbonate bisphenol A oligosulfones obtained in a wide concentration range. Physical and mechanical properties of composites are investigated. The compatibility of the obtained oligosulfones with polycarbonate was studied using viscometry, differential scanning calorimetry, and probe microscopy. It was shown that the introduction of oligosulfones into the polycarbonate matrix promotes an increase in the glass transition temperature, found by differential scanning calorimetry, at 3 to 20 ° C, depending on the composition, the composites have good dielectric and technological properties. The temperature dependences of the dielectric properties of PCs and PC-based composites with different oligosulfone content are characterized by the presence of a single loss on the dielectric loss tangent dependences on the temperature.
Improving the fire resistance of PVC plastic the introduction ammonium octamolybdate
Authors: Borukaev T A , Kharaev A M , Shaov A Kh , Borodulin A S , Kalinnikov A N
Published: December 2019

An efficient method for the synthesis of ammonium octamolybdate with a quantitative yield has been developed. Compounds based on PVC plastic and octamolybdate are obtained. It was found that the introduction of ammonium octamolybdate in PVC plastic leads to an increase in the fire resistance of the compound and to a decrease in smoke formation during its combustion. At the same time, the mechanism for reducing smoke emission during PVC plastic combustion in the presence of ammonium octamolybdate consists in its catalytic action in the conversion of soot particles into various oxidized forms. It is shown that PVC plastics containing ammonium octamolybdate have elevated oxygen index and coke residue.
Technology of applying antifriction coatings using an electric arc pulsating power
Authors: Kravchenko I N , Petrovsky D I , Glinsky M A
Published: December 2019

The coating of a mechanical mixture of metal powders and solid lubricant material is due to difficulties due to the low adhesive and cohesive strength of the resulting coatings. This problem can be avoided when using in the process of the pulsating power electric arc (PPEA). The object of research in the paper is an anti-friction coating based on ΠΓ-XH80CP3 powder with the addition of 20% by volume of graphite ΠΓ-50, of which plasma coating using PPEA gave a coating with friction coefficients fmp min = 0.038 and fmp max = 0.062 under contact load of 300 MPa. The test results of a friction pair, carried out for 500 hours on a path of friction of 55,000 m, showed the stability of the friction coefficient within fmp = 0.056 … 0.061. The application of the coating process using the surface activation of the PPEA allowed us to obtain high-strength anti-friction coatings with the content of a solid lubricant element in the coating composition up to 20% of the total coating volume.
Engineering and technological methods of ultra-jet diagnostics of complex-profiled products made of composite materials
Authors: Barzov A A , Belov V A , Galinovsky A L , Mazaeva I V
Published: December 2019

An engineering technique for ultra-jet diagnostics of the state parameters of complex profiles surface layer of polymer composite materials which are obtained by winding or laying is proposed. The possibility of increasing the accuracy of obtaining express-diagnostics results under varying conditions of interaction of the hydro-ultra jet with the test surface is shown.
Microporous PVDF ionic membranes for actuator applications prepared with imidazole-based poly(ionic) liquid as a pore forming material
Authors: Morozov O S , Shachneva S S , Kepman A V
Published: December 2019

The microporous poly(vinylidene fluoride) (PVDF) membranes were prepared by phase inversion process using poly(1-ethyl-3-vinylimidazolium tetrafluorborate) (PIL) as a pore-forming agent. The membranes were activated by soaking in room temperature ionic liquids (EMImBF4 and BMImBF4) as a liquid electrolyte. The influence of PIL content on morphology and structure, electrolyte uptake of porous membranes and ionic conductivity of the activated membranes were investigated. The properties of the PVDF microporous membranes, such as crystallinity and porosity were characterized. The membrane with the maximum porosity demonstrates the highest electrical properties. The electrolyte uptake of EMImBF4 is 210 wt.% and the ionic conductivity is 9.2 mS/cm. Actuators with carbon nanotube bucky gel electrodes based on obtained membranes were prepared. The influence of ionic liquid and actuator thickness on electromechanical properties was discussed. The actuators with BMImBF4 as a electrolyte demonstrated high blocking force up to 9.5 mN.
Development of the radiant heating facilities for the testing of ceramic materials with operating temperatures up to 2000 K
Authors: Baldzhiev R S , Prosuntsov P V , Zabezhailov M O
Published: December 2019

The radiant heating facilities based on tungsten halogen lamps are frequently used for high-temperature materials experimental study and aerospace hot structures functional testing. The ease of maintenance and operation as well as the relatively low cost and high efficiency are the main advantages of halogen lamps as a heating source. However, the significant disadvantage of halogen lamps is the limitation of the facility operating temperature. It could not exceed 1500 K due to the tungsten-halogen cycle disruption. Current paper investigates the feasibility of the facility operating temperature expansion up to 2000 K by means of the lamps cooling with a compressed air flow. The mathematical simulation of a complex heat transfer in the facility operating area was performed. The design-layout schemes for several facilities were proposed. The modelling results proved the performance of the proposed design-layout schemes.
Study of the GTE stator vane samples made from a Al-SiC metal matrix composite reinforced by SiC.
Authors: Berezovskiy V V , Kurganova J A
Published: December 2019

Al-SiC system metal matrix composites application in gas turbine engine ventilator stator blade is shown. Mechanical properties of Al-SiC system metal matrix composite in comparison with aluminum and titanium alloys is shown. Mechanical properties of gas turbine engine ventilator stator blade is shown.
Design calculation of braided high-temperature composite structures
Authors: Smerdov A A
Published: December 2019

Following a review of published papers devoted to calculations of braided composite structures, basic requirements for computational models are formulated. A mathematical model intended for design calculations of braided structures of shells of revolution is presented. The dependences for calculating the stiffness, thermal deformation, and strength characteristics of a braided composite material are given depending on the braiding scheme, reinforcement angle, and the current radius of the shell. The relationship between the angle of reinforcement, the thickness of the single-pass layer and the coverage rate of the structure that determines the degree of continuity of the layer is investigated. The features of calculations of structures with a two-axis and three-axis braiding scheme are discussed. Examples of calculations of specific composite structures are given, the dependences of elastic moduli, coefficients of linear thermal expansion and ultimate strengths on the variation of the radius of a typical braided carbon-ceramic composite shell are demonstrated.
The effect of triethylene glycol additive on the self-healing properties of epoxy binder
Authors: Petrova T V , Solodilov V I , Kabantseva V E , Karelina N V , Polezhaev A V
Published: December 2019

A triethyleneglycol-modified epoxy composition based on diglycidylfurfurylamine (FuEp) and 1,1’- (methylene-di-4,1-phenylene)bismaleimide (BMI) was cured with methyl hexahydrophthalic anhydride (MHPPA). The components of the composition can reversely binds through Diels-Alder reaction between furan and maleimide moieties. We studied the effect of TEG additive on the rheological and thermophysical properties of the binder, as well as the ability through thermal treatment. All compounds were characterized with NMR and IR spectroscopy. It was shown that TEG significantly reduces the curing time and the glass transition temperature of the cured samples, which allows to speed up the process of self-healing.
Finite element modelling and multi-objective optimization of composite submarine pressure hull subjected to hydrostatic pressure
Authors: Fathallah E , Helal Mahmoud
Published: December 2019

The design of submarine pressure hull made of laminated composites depends on number of layers and fibre orientation of ply angle. In the present study an overview and comprehensive study about the multi-objective optimization of composite pressure hull under hydrostatic pressure to minimize the weight of the pressure hull and increase the buckling load capacity according to the design requirements. Three models were constructed, two models constructed from Carbon/Epoxy composite (USN-150) with and without core layer the third model is metallic submarine hull constructed from HY100. The low-density PVC foam material is used as a core material. The optimization process is carried out in ANSYS Parametric Design Language (APDL). The constraints on the optimization process are Tsai-Wu and maximum stress failure criteria. The results obtained emphasize that, the submarine constructed from Carbon/Epoxy composite (USN-150) is better than the submarine constructed from HY100. Furthermore, the submarine constructed from carbon fiber-epoxy composite (USN-150) with core layer is better than the submarine constructed from carbon fiber-epoxy composite (USN-150) without core layer. Finally, an optimized model with an optimum pattern of fiber orientations was presented. Hopefully, the results may provide a valuable insight for the future of designing composite underwater vehicles.
Study of the effect of permeability coefficients in a threedimensional formulation for fabrics various types of fabric structures
Authors: Maung Pyi Phyo , Malysheva G.
Published: December 2019

The results of theoretical and experimental studies of the kinetics of the impregnation process for 4 types of woven structures depending on the thickness of the molded parts are presented. The calculations were carried out with and without the permeability coefficient in the z plane. All calculations were performed in the PAM-RTM program. It has been established that considering the permeability coefficients along the x, y, z axes allows to increase simulation accuracy. As a result of the research it was found that with increasing laminate thickness more than 3 mm, it is necessary to consider the influence of the coefficient of permeability in the z-plane. Simulation error without taking into account the through thickness permeability coefficient increases from 6% to 22%.
Analysis of anisotropy of time-dependent and nonlinear properties of unidirectional CFRP
Authors: Dumansky A M , Liu Hao
Published: December 2019

Analysis of unidirectional carbon fiber reinforced plastic AS4/3501-6 regularities under strain-rate compression was given. Constitutive equations based on nonlinear hereditary mechanics relationships under shear in plane of the layer were elaborated. In order to obtain the constitutive equations, which are allowing describing the stress-strain curves of unidirectional carbon-fiber reinforced specimens under compression at different angles to the direction of reinforcement in the linear region, the algebra of resolvent operators and the relations of the elasticity theory of an anisotropic body were used. The possibility of correct using of the elaborated approach was shown.
Investigation of mechanical characteristics of a carbonceramic composite material based on a braided preform
Authors: Baryshev A N , Kulish G G , Smerdov A A , Timofeev I A , Tsvetkov C V
Published: December 2019

An experimental analysis of characteristics of a carbon-ceramic composite material based on a braided preform in a plane stress state was carried out. The technical limits of strength and elastic characteristics of the material are determined. Tests of tubular specimens in a complex stress state allowed us to obtain the data necessary for the constrction of the failure criterion. The possibilities of using various failure criteria of the composite are investigated. The contours of the surface of the strength of the material in the space of stresses at the intersection of its coordinate planes are built.
Atomic force microscopy of titanium oxide nanostructures with forming-free resistive switching
Authors: Avilov V I , Smirnov V A , Tominov R V , Sharapov N A , Avakyan A A , Polyakova V V , Ageev O A
Published: December 2019

The paper presents the results of study of the resistive switching effect in titanium oxide nanostructures obtained by local anodic oxidation. It was shown that the resulting structures exhibited a forming-free resistive switching effect. Analysis of the current-time characteristics made it possible to obtain a resistance ratio in the HRS and LRS states of about 70. The formed LRS regions persisted for 75 days.
Microscopy investigation of conical and layered nanowires
Authors: Cherkasov D A , Panov D V , Doludenko I M , Kanevskiy V M , Muslimov A E , Zagorskiy D L , Biziaev D A , A Bukharaev A
Published: December 2019

This article discusses the use of scanning microscopy in the study of one-dimensional nanostructures – nanowires. The nanowires were produced by matrix synthesis. Atomic force microscopy (AFM) of conical nanowires was carried out, and layered nanowires were investigated by AFM and magnetic force microscopy (MFM) methods.
Study of structure-property relationship in steels based on analysis of EBSD data
Authors: Chikova O A , Chezganov D S , Yuzhakov V V , Sinitsin N I
Published: December 2019

In this work, we formulate novel data-driven assays for exploring the structure-property linkages for high-manganese austenitic wear-resistant steel 110G13L (Hadfield steel). Steel 110G13L has the following chemical composition, wt.%: C(0.95-1.50)-Mn(11.5-15.0). These assays are built on recent advances in high resolution quantification of material structure using correlations and principal analyses of electron backscatter diffraction (EBSD) data, as well as in the mechanical characterization using nanoindentation. These novel protocols are demonstrated on a steel 110G13L that exhibits various polycrystalline microstructures. A comparative analysis of EBSD data was carried out for samples of manganese steel 110G13L obtained by various methods. Analysis of the diffraction patterns of backscattered electrons allowed us to plot orientation maps, Schmid factor maps and distributions for austenite dendrites. Schmid factor maps are used to determine the degree of homogeneity of a possible deformation. The results of the measurement of hardness and Young’s modulus for the austenite dendrites indicate the heterogeneity of the mechanical properties of the material in submicro-volumes due to lattice defects (dislocations) inside the crystallites.
SEM investigation of the microstructure of cast CuNiAlCoFe equiatomic high entropy alloy
Authors: Chikova O A , Chezganov D S , Tsepelev V S , Yu Ilyin V
Published: December 2019

Microheterogeneity and crystallization conditions of the equiatomic high-entropy CuNiAlCoFe alloy were studied by measuring the viscosity during heating/cooling, as well as visualizing the microstructure after solidification. The CuNiAlCoFe liquid alloy showed different temperature dependences of viscosity upon heating to 2070 K and subsequent cooling. Since the coinciding part of the temperature dependences was absent, complete destruction of the microheterogeneity of the melt after heating to 2070 K did not occur. Heating the melt to higher temperatures was not possible due to the evaporation of the metal. The melt viscosity during cooling is higher than that during heating; this is observed when microheterogeneity is dispersed. The CuNiAlCoFe alloy obtained as a result of the experiment at a crystallization rate of 10 K/s had a typical microstructure of cast dendrite. Dendrites consisted of a eutectic (α-Al+CuAl2+Cu4NiAl7) and included primary crystals of CoCu2Al7 and FeCu2Al7. The interdendritic space contained small Cu4NiAl7 crystals.
Domain structure of CoNi microparticles under mechanical stress
Authors: Nurgazizov N I , Chuklanov A P , Biziyaev D A , Bukharaev A A , Chirkov V V
Published: December 2019

In this work, the results of the study of the domain structure of planar CoNi microparticles are presented. The microparticles represented squares with a side of 7 μm and height of 0.03 μm. It was shown that in the non-stressed state the particles had the regular four-domain state. The mechanical stress (compression) of the particles led to a change in domain size, which depended on the degree of compression, the angle between the direction of magnetization, and the side of the mechanical stress. Under the mechanical stress, the change in the coercive force and the residual magnetization of the particles was observed.
Gas sensing properties of individual composite nanostructures TiO2-x/MWCNT and SnOx/MWCNT measured by scanning probe microscopy
Authors: Davletkildeev N A , Sokolov D V , Mosur E Yu , Bolotov V V
Published: December 2019

The gas sensitivity properties of individual composite nanostructures based on multi-walled carbon nanotubes (MWCNT), functionalized by argon ions and coated with tin and titanium oxides, were investigated by the methods of scanning probe microscopy. The Fermi level shift and the change in longitudinal conductance of nanostructure upon absorption of ammonia and nitrogen dioxide are determined. It is shown that the change in conductance of the composite nanostructures correlates with the Fermi level shift under gases exposure as a result of charge carrier concentration changing in the metal oxide surface layers upon adsorption of gas molecules.
The effect of optical cooling of the SPM probe in the optomechanical resonator
Authors: Dunaevskiy M S , Alekseev P A , Sharov V A , Baranov A
Published: December 2019

Optomechanical resonators formed by the surface of an emitting semiconductor laser and the reflective surface of the probe of scanning probe microscope (SPM) were studied. The use of scanning probe microscopy techniques allowed studying the properties of such optomechanical resonators in details. The effect of optical cooling of an SPM probe in an optomechanical resonator was investigated by measuring the spectra of thermal vibrations of an SPM probe. Minimal achievable temperatures of SPM probe cooling were experimentally established.
Electron beam processing of 6H-SiC substrate to obtain graphene-like carbon films
Authors: Gusev E Yu , Dudko V G , Avramenko M V , Karmanov M P , Avdeev S P , Kolomiytsev A S , Ageev O A
Published: December 2019

We report on growth of graphene-like carbon films on 6H-SiC {0001} substrate by electron-beam. The processing was carried out on a specialized electron beam system with the Pierce electron gun. The D, G, and 2D peaks as well as D/G (0.2-0.9) and 2D/G (0.7-0.9) ratios are detected on processed samples by Raman spectroscopy. The prominent bands D, G, and 2D are located at 1350, 1584, and 2707 cm−1, respectively. Atomic force microscopy showed that the average roughness lies in the range from 5 to 30 nm, and ten point height – from 40 to 200 nm. The results demonstrate that the electron-beam technique is appropriate to form graphene-like structures directly on 6H-SiC substrates and could be used for electronic device fabrication.
Uncertainty of tunnelling microscopy measurements of the field emission from multilayer nanostructures
Authors: Panfilova E V , Syritskii A B , Ibragimov A R
Published: December 2019

The paper presents the results of scanning tunnelling microscopy investigation of electron field emission from multilayer nanostructures based on silica opal film Cr-SiO2-Au-C. Opal film was deposited in colloidal solvent, while other films – by vacuum deposition methods. We discuss the problem of uncertainty of measurements of the field enhancement factor and carbon nano-edge sizes using the current versus applied voltage characteristics of the emission. Field enhancement factor is defined as the ratio of the electric field at the nano-edge to the field applied to the gap. We found that at well-controlled experimental conditions the combined uncertainty of field enhancement factor measurements is ∼15% based on a 95% confidence interval and the combined uncertainty of nano-edge sizes measurements is ∼18% based on a 95% confidence interval.
High temperature superconductivity at the interface Ba0.8Sr0.2TiO3/La2CuO4
Authors: Pavlov D P , Piyanzina I I , Garig’yanov N N , Salikhov T M , Chibirev A O , Gilmutdinov I F , Yusupov R V , M Mukhortov V , Adachi T , Kawamata T , Koike Y , V Kabanov V , F Mamin R
Published: December 2019

We present the results of the investigations of high conducting area and superconductivity at the interfaces between ferroelectric oxide and insulating oxide in heterostructures, isostructural to BaTiO3/La2CuO4. The performed numerical simulations of BaTiO3/La2CuO4 heterostructure show the possibility of high conductivity state at the interface. The temperature dependence of the measured electrical resistance of the Ba0.8Sr0.2TiO3/La2CuO4 heterostructure interface have been studied and the superconducting behaviour with transition temperature Tc about 30K has been found. Therefore, the transition to the state with 2DEG at the interface is demonstrated. The results offer the possibility to design novel electronic devices.
Radial non-uniform piezoelectric response of perovskite islands in thin PZT films
Authors: Senkevich S V , Kiselev D A , Ilina T S , Osipov V V , Elshin A V , Pronin V P
Published: December 2019

A comparative study of the morphology and piezoelectric response of island and continuous perovskite thin PZT films deposited on a platinized silicon substrate Si/SiO2/TiO2/Pt was carried out. It was shown that the self-polarization value of micron-size island films was about 1.4 times higher than that of continuous films. It is assumed that the difference is due to the relaxation of tensile mechanical stresses caused by silicon substrate at the island periphery.
Scanning probe microscopy investigation of iron garnet films for magnetoplasmonics
Authors: Shaposhnikov A N , Lyashko S D , Nedviga A S , Karavainikov A V , Yu Semuk E , Vysokikh Yu E , Mikhailova T V
Published: December 2019

Topography and domain structures of Bi-substituted iron garnet films proposed for magnetoplasmonic applications are presented. Investigations were carried out by scanning probe microscopy methods, including polarization near-field optical microscopy. The most suitable films with less rough surface were chosen. The period of domain structure of sputtered film of composition Bi2.8Y0.2Fe5O12 were determined, 2w = 0.5 μm.
The SPM study of oligonucleotides consisting of repeated nucleotide sequences
Authors: Sharipov T I , Garafutdinov R R , Amangulova I T , Bakhtizin R Z
Published: December 2019

Recently, the study of the dependence of the physical characteristics of DNA molecules on their structure has become of considerable interest. Various methods are used to conduct such research, among which scanning probe microscopy (SPM) is becoming increasingly important. In this work, the short single-stranded DNA molecules consisting of dC nucleotides are visualized and their conductivity is investigated by SPM methods. It has turned out that the distribution of DNA molecules on the surface of the substrates is uniform. The measured current-voltage characteristics have made it possible to estimate the differential electrical resistance of individual d(C)12 molecules.
Conductive AFM study of the electronic properties of individual epitaxial GaN nanowires
Authors: Sharov V , Bolshakov A , Fedorov V , Shugurov K Yu , Mozharov A M , Sapunov G A , Mukhin I S
Published: December 2019

In this work, we use conductive atomic force microscopy (CAFM) to study the impact of substrate surface preparation and buffer layer composition on the electrical transport properties of GaN nanowires (NWs). I-V curves of single NWs from seven differently prepared samples were obtained. The tip of atomic force microscope (AFM) was used as a top conductive electrode to create stable electric contact to NW free upper grain, while the bottom contact was established between the highly doped Si substrate and a grounded sample holder of the AFM device. Single NW I-V curves were compared to those of NW arrays. The difference between them was discussed.
SEM and SPM investigations of the surface of antifriction aluminium alloys of the system Al-5%Si-4%Cu-6%Sn
Authors: Shcherbakova O O , Muravyeva T I , Zagorskiy D L , Shkalei I V , Lapitskaya V A , Kuznetsova T A
Published: December 2019

Two antifriction alloys based on the Al–5%Si–4%Cu–4%Sn system with the addition of bismuth, lead, and cadmium were investigated. The effect of these elements on the change in surface topography and the tribological properties of the samples was studied. Tribological tests simulating the work of the friction unit were carried out using “shoe-roller” scheme. After heat treatment in both alloys, the phase components acquired a globular shape. Mass transfer between the shoe and the roller led to the formation of a film of secondary structures of variable thickness on the roller surface. SEM and EBSD allowed observing a near-surface layer (50-100 μm thick) with a modified structure and grain shape. SPM made it possible to evaluate the difference in the mechanical properties of the surface layer at the nanoscale level. It was shown that the material was strengthened in the process of friction.
Formation of the maze domain structures in lithium niobate as a result of multiple pulse irradiation by infrared laser
Authors: Shur V Ya , Mingaliev E A , Kosobokov M S , Makaev A V
Published: December 2019

The formation of the maze domain structures in the plates of congruent lithium niobate single crystal caused by multiple irradiation of infrared pulsed laser at different plate temperatures was studied. Four stages of domain evolution with increasing pulse number were distinguished. The dependence of the formed self-organizing domain structures on pulse number and sample temperature was revealed. Suppression of the domain formation at the elevated temperatures was attributed to increasing ionic conductivity, which led to decreasing the switching field.
Forming-free resistive switching in nanocrystalline hafnium oxide films
Authors: Smirnov V A , Tominov R V , Avilov V I , Avakyan A A , Ageev O A
Published: December 2019

This work presents the results of the investigations of resistive switching effect in Si(100)/HfO2 structure. It was shown that resistive switching from HRS to LRS occurred at 0.4±0.1 V, and from LRS to HRS at -0.5±0.1 V. An increase in the sweep voltage from 1 to 5 V led to a decrease in the HRS/LRS ratio from 606±36 to 204±11. Thus, it was shown that the nanocrystalline HfO2 film resistance varied within two orders of magnitude at a sweep voltage of 1 V within 15 measurements. The results can be useful for manufacturing neuromorphic systems based on forming-free nanocrystalline HfO2 films.
Microstructure of barium strontium titanate based glass-ceramics doped by Ce and La
Authors: Turygin A P , Chezganov D S , Baturin I S , Song X , Zhang Y , Shur V Ya
Published: December 2019

The microstructure and surface morphology of (Ba0.8,Sr0.2)TiO3 based glass-ceramics with different amounts of La and Ce were studied. It was shown that the addition of the 1.5% La and >2%Ce led to formation of dendrite-like structures. The isolated clusters of ferroelectric phase were found in all investigated samples. Fraction of ferroelectric phase was about 0.75% for La addition and 0.25% for Ce addition.