The manuscript presents results of a study ferroelectric ceramic metaniobate lithium (PCR-61) which containing Li2O, Nb2O5 and CaO in the fallowing ratio, mass. % Li2O 10,03-10,10; Nb2O5 89,22-89,87; CaO 0,03-0,75. The most effective was the offset component in alcohol and air environments, which providing sufficiently high rate of sintering, the formation on their base high density ceramic with the most perfect crystal structure and microstructure of the equilibrium. Using the foregoing results the solid phase material was prepared by one-stage synthesis (SPS) for Tsint.1 = 820℃, τ = 5h. with followed by sintering by conventional ceramic technology (CCT) (without pressure) at a temperature Ts. = 1150℃, τ = 2h. After machining, the samples were polarized ("oil" polarization). The promising method SPS + CCT was presented. Material based on piezoelectric ceramics metaniobate lithium (PCR 61) was obtained by the SPS + CCT, close to the parameters of hot-pressed (HP) samples and can be used in electrical devices under the influence of ultra-high temperatures. The effectiveness of heterovalent modification as a method of directional changes in the properties of lithium metaniobate was shown.
Keywords: ferroelectric ceramics, metaniobates lithium, solid-phase synthesis, conventional ceramic technology, the electrical properties, high temperature technology
Zinc electrodeposits gained the distribution generally thanks to high protective properties. However it is possible to apply zinc electroplated coatings and at restoration of worn-out surfaces of details of cars. Thus zinc electrodeposits possess the high durability of coupling with a substrate that is pledge of long-term service of the details restored by zinc. Ensuring high durability of coupling of zinc electroplated coating with a basis possibly only at careful observance of technological process of preliminary preparation of a surface for sedimentation and directly the sedimentation. Some researchers suggest to estimate the received durability of coupling of a covering with a basis from the point of view of the theory of reliability. Technological reliability of process of preparation of details for galvanizing is meant as percent of the restored details, with a high durability of coupling. Process of preparation represents technical system in which operations act as elements. Reliability of technical system are defined by quantity and reliability of elements, their functional communication. And reliability of elements, is defined by technology factors and depends on quality of carrying out the previous operation. Refusal of any of elements causes refusal of all technical system. That is communication between elements of system consecutive and it is possible to apply the second theorem of probabilities according to which the probability of joint emergence of several dependent events is equal to work of probability of one of them on conditional probabilities of all others to it. It is necessary to understand change of reliability of an element in time as stability of reliability. For the purpose of improvement of technological process of galvanizing it is possible to perform operation of anode etching directly in galvanizing electrolyte. Thus the block diagram of preparation of a detail can be submitted as follows: machining; degreasing of surfaces of a detail Vienna lime; washing in cold water; anode etching galvanizing electrolyte; removal of products of etching from the covered surfaces and an exit to the mode; galvanizing.
Keywords: case detail, restoration, repair, defect, resource way of restoration, car repair production
The choice of the electrolyte for the galvanic deposition of coatings is one of the fundamental points to ensure high quality and reliability of the reconstruction of surfaces of machine parts. Zinc electroplated coatings currently used in the automotive and car repair production mainly as protective coatings. However, in addition to the protective properties of zinc galvanic coating has sufficient hardness and wear resistance, and damping characteristics. From the composition and type of the electrolyte depends on the quality of sediment, its continuity, physical and mechanical properties, adhesion to the substrate, and the performance of the deposition process, the service life of the electrolyte, and the frequency of service (filtering, correction, and so on), the mechanism of occurrence of electrolysis, types and rate of the electrochemical processes. When the metal plating of zinc are used mainly the following types of electrolytes: slightly acidic; acidic, coroborate, chloride, soleplate; alkaline, and mixed electrolytes. In use, in practice, the greatest use of acid, weakly acidic and alkaline. The optimal choice of the electrolyte galvanizing ambiguous, as the process of electrolysis depends on many factors and is characterized by more than twenty different indicators. The analysis showed that the main selection criteria are: quality of galvanic sludge - corrosion resistance, adhesion to the substrate, the distribution of sediment thickness, aromatherapist, flexibility, adaptability to soldering and decorative properties; technological parameters of deposition - the range of the cathodic and anodic current density, the productivity of the deposition, the temperature of the electrolyte, the velocity of the electrolyte, etc.; safety for humans and the environment; saving resources and costs; the stability of the electrolyte and ease of maintenance.
Keywords: passive film, adsorption, sedimentation productivity, electrocrystallization, mechanical activation, crystal lattice
Abstract: the Article is devoted to the problem of waste production during construction, operation and liquidation of coal mines of Russia. This work suggests that waste recycling technologies, including for reception of energy based on the modeling and system analysis of the biocenosis. The possibility of realization of innovative methods of processing plethodon using the biocenosis. Quite detailed questions transformation of industrial waste into energy through anaerobic bioconversion. As part of a description of the proposed methodology presents the results of field experiments and action program of recycling of materials at the stage of commercial operation. In particular it justifies the optimization of processing technology on the basis of the selection of the most active biocenosis of microorganisms. Theoretical developments are confirmed by practical data.
Keywords: disposal, technogenic resources, plothole, biotechnology, biotransformation, biocenosis, recycling
Carrying out anode etching of details directly in working electrolyte of galvanizing will allow to reduce significantly time for preliminary preparation of the restored surface for sedimentation and to increase stability of results on ensuring quality of a covering. Anode etching represents electrochemical processing during which there is a removal of oxidic films, dissolution defective superficial a metal layer, revealing its structure. Thus on an anode surface the slime consisting of etching products is formed and ions of bivalent iron get to electrolyte. At achievement of a certain (critical) value of density of anode current the process of passivating of a surface, that is a surface covering a passive film which is followed by sharp increase of tension and decrease in current begins. There is a rough allocation of the small vials of oxygen clearing slime from an anode surface. The mechanism of anode etching of surfaces of the restored details of cars in sulfate electrolyte of galvanizing is similar to etching in the electrolytes containing sulfate ions that is as a result of process of formation of an oxidic film and parallel electrochemical dissolution by its anions. Quality of electroplated coatings of the restored details of cars zinc is provided with anode etching on necessary depth before emergence of steady passivation and the subsequent covering of a surface a continuous passive film. The mechanism of passivation of a surface of the anode in the electrolytes containing sulfate ions can be described by two theoretical models: 1) passivation is caused by protection of a surface an oxide layer of metal; 2) passivation is caused by special nature of adsorption of ions of oxygen. At achievement of anode density of current of a certain (critical) value, and change of active dissolution of a surface by the steady passivation which is followed by formation of a monomolecular passive film happens an electrode of a certain value of potential.
Keywords: anode etching, passive film, current density, adsorption, passivating, potential
The implementation of electrochemical research is needed to identify the nature and magnitude of the impact of the main technological factors on the processes taking place during anodic etching of grey cast iron in the electrolyte on the basis of sulphate of zinc. The main technological factors that affect electrochemical processes occurring, is the temperature and acidity of the electrolyte, the concentration of the basic salt of zinc in the electrolyte and other components, the speed of flow of the electrolyte in the cathode space, the cathodic and anodic current density, rotation speed of the electrode, modes of mechanical activation. Electrochemical studies were carried out in three modes: potentiometric, potentiostatic and galvanostatic. Resulting in the obtained polarization curves for all three modes. To identify the degree of influence on the growth of the limiting cathode current density of mechanical activation of the cathode surface was carried out electrochemical studies, which were obtained cathode potentiometric curves. These studies took place with anode under similar research conditions in the same laboratory setting. The main difference cathodic electrochemical studies was that mechanical activation of the rotating electrode was carried out by introducing into the electrochemical cell of the lever, with a fixed abrasive material, pressing it against the surface of the test electrode. Thus, this electrode has already played the role of the cathode. Conducting electrochemical studies of the behavior of iron in sulfuric acid electrolyte galvanizing by etching, mechanical activation of the cathode surface and deposition of the electroplated layer, allowed us to obtain sufficient experimental data to identify rational modes of electrolysis at all stages.
Keywords: technological factor, electrochemical studies, polarization curves, electrochemical cell, electrode potentiostat
In this paper we attempt to quantitatively describe the process of diffusion of Nickel atoms to the copper substrate, taking into account the accelerated diffusion along the grain boundaries. A model experiment allows us to get guidance on the selection of the optimum thickness of the Nickel coating to ensure stable operation of wire with desired characteristics
Keywords: Nickel coating, the optimum thickness, copper wire, enhanced diffusion, diffusion coefficient, diffusion distribution of atoms, the grain boundary, modeling, task Fisher
The main mission of a cargo spacecraft is a cargo delivery on the ISS. The cargo positioning on the spacecraft board is realized on the Earth according to certain rules. The main limitations of the cargo positioning is the weight limitation, the volume limitation, the mass center limitation and the unloading sequence on the ISS. If the mass center deviation will be greater than a some default value, the replacement of cargo must be performed. It maybe more than one cargo replacement realized that leads to increase of complexity and duration of the spacecraft prepare procedure. So, the problem of aprioristic finding the cargo optimal placement on a cargo spacecraft board arises. The solution of this problem will make it possible to give some advice on the optimal cargo placement to the staff performing the spacecraft prepare procedure.
Keywords: cargo spacecraft, cargo placement, weight, volume, mass center, unloading sequence, optimal placement
In this article authors examine integrated method of ring cross-section concrete constructions diagnostics after the example of overhead contact system pylons. Complex physical-mechanical process of carcass and concrete working needs to take into consideration the state of these components. Authors suggest modern device of magnetic-particle method making for carcass state rating and its location in a pylon body. Concrete jacket defectoscopy may be done with modified device population of ultrasonic diagnostics. Examination zones of constructions are found depending on pylons workload scheme. The authors give correlations which let determine parameters of destructions (cracks) that lead to degradation of load-carrying capability. In the article there are graphic materials got as a result of ultrasonic inspection and mathematical expressions for estimating of residual load-carrying capability with a glance of carcass and concrete destructions.
Keywords: overhead contact system pylons, residual load-carrying capability, ultrasonic diagnostics, hodograph, cracks, carcass corrosion, technical state
The purpose and objectives of this work consist in the development of regularization methods for solving systems of linear equations. For their achievements in this paper we propose a modified least squares method for solving systems of linear equations, which is based on the use of q-differentiation. Calculations based on a test of task performed in Matlab mathematical package, confirmed the adequacy of the method and in some cases have shown its advantage over traditional methods for the regularization of systems of linear equations.
Keywords: system of linear equations, the objective function, the gradient method, iterative method, modeling, algorithm, function extremum, q-derivative, relative error, norm of the vector, the conditionality of the problem
In order to assess the strength of the bone tissue in patients undergoing joint replacement of the knee or hip joint, resected bone fragments were tested on a test-stand, ИСС/М-Scaime ZF-500, installed at the department of traumatology and orthopedics of the Rostov state medical university. Later, the bone strength indicators were compared to the following: data obtained from densitometry, gender, age and the osteoporosis risk factors of the patient. Based on multivariate analysis, medical treatment and rehabilitation methods were devised for the patients after a joint replacement of the knee or hip joint.
Keywords: osteoporosis, osteopenia, bone strength, knee joint replacement, hip joint replacement, test-stand.
In this work the problem definition of the country and city of object of a geolocation on the basis of its coordinates is considered (latitudes and longitudes). The main objective of work is the automated determination of location and a binding of location-based objects to the countries and the cities in the world. The received algorithm allows to define concrete location of objects in a format of the countries/cities and to create own base that is actual for the majority of location-based web services and appendices, and also provides the decision for the following circle of tasks: definition of the country and city of object on the basis of its coordinates; formation of statistical these objects on the basis of the made base of the cities and countries; automatic expansion of base of the cities and countries at addition of bigger number of objects; possibility of a filtration of objects about the country or to the city.
Keywords: geolocation, the location-based Google service, determination of location of object, the automated finding of location-based object, location-based web service.
Two approaches are proposed for constructing a road graph for routing mobile robot in a closed system of corridors with a focus on the use of the robot computer vision to identify the entrances to the rooms from the hallway. In the first version of the graph the vertices correspond to the two types of objects: connection points (branching intersection) corridors and location of entrances - each input corresponds to only one vertex. The second version for the formation of the graph allows to concider returns of the robot and the robot motion in the joints of the corridors. For each room's entry formed two vertices to describe the robot motion in all directions.
Keywords: routing, road graph, mobile robot
This article describes the issues on the basis of scientific research and the data produced in-depth analysis of technical condition of water spending long maintained facilities for further classification of defects and damages, as well as the prediction of their remaining life. Mathematical and software was built on the length of the projected water filtration since the beginning of the construction survey. Program - technical complex in the survey predicts the loss of bearing capacity as the structure as a whole and its constituent elements from the moment of injury. In the future, software and hardware predicted time total loss bearing capacity of the construction, using various regression dependence. Technical possibilities of application systems allow calculation of the geometric characteristics of different defects and damages on the surface of structures, and in some of its elements. Presented Program - technical complex for solving the problem of forecasting residual resource of water conveyance structures can be used to create a database during the operation of these structures over a long period of operation that will extend the life cycle of water conveyance structures with regard to their reliability parameters. The basic provisions on the organization of determination and prediction of residual life long maintained water conveyance structures, identification of defects and damages, assessment of suitability taking into account the reliability of the parameters, for further use water conveyance facilities.
Keywords: monitoring, automation, carrying water facilities, livneotvodyaschie facilities, software and hardware, reinforced concrete, technical condition.
The architecture of the distributed information systems (IS) is considered, with use of the office of the closed systems of mass service (SMS) and a method of the enclosed Markov's chains the analitiko-numerical model of this class IS with remote execution in the conditions of the low level of load of a network traffic is developed. The following stages of creation of this model are offered: conceptual representation of functioning of system; formation of full space of conditions of the chain of Markov enclosed in casual process; a choice of the moments of regeneration of messages in system; definition of space of conditions of a chain of Markov taking into account restrictions; calculation of a matrix of transitional probabilities; receiving formulas of calculation of characteristics of the distributed IS on the basis of a vector of the stationary distribution of probabilities (SDP) at the moments of regeneration of messages. The analitiko-numerical model offered and in detail considered in article can be realized in any high-level programming language and respectively serve as the highly effective tool for carrying out experiments with a research objective of behavior of the distributed IS at various values of its external and internal parameters.
Keywords: the distributed information system, replication, network traffic, remote execution, Poisson stream, erlangovsky stream, method of the enclosed Markov's chains, space of states, the moments of regeneration, matrix of transitional probabilities