166 research outputs found
Octahedral slip in nickel single crystals induced by scratch testing
Investigation of the effect of crystallographic orientation on mechanical properties, behavior under loading, or deformation relief of single crystals is topical. One of the methods that make it possible to achieve unambiguous mutual orientation of the material structure and the applied load is scratch testing. This research is aimed at establishing the features of the deformation relief formation under various crystallographic conditions (orientation of the plane and scratch direction). The paper presents the experimental results on scratch testing on single crystals of nickel. The face of a single crystal (010) and two scratch directions [001], [–101] were investigated. The scratch testing parameters at which slip begins on the {111} planes have been determined. It is shown that the slip is activated most easily in the systems parallel to the direction of the indenter movement and in the systems oriented thereto at an angle of 45°. Three stages are identified on the scratch friction force vs normal load (F-N curve) and the correlation of the stages with the beginning of the shear traces formation is shown. The parameters of the transition to the third stage of the F-N curve and the magnitude of the friction force for scratch testing depend on the crystallographic orientation direction of the indenter movemen
FRICTION BEHAVIOR OF ALUMINUM BRONZE REINFORCED BY BORON CARBIDE PARTICLES
A promising composite material for tribotechnical applications based on aluminum bronze with reinforcing boron carbide particles fabricated by a special electron beam additive deposition technique was studied experimentally and numerically. Tribological experiments showed that reinforcing by carbide particles allowed reducing the coefficient of friction from 0.26 to 0.19 and improving the wear resistance by 2.2 times. Computer modeling reveals two main factors playing a significant role in the friction behavior of the studied metal matrix composite: the mechanical effect of reinforcing ceramic inclusions and effective hardening of the metal matrix due to the peculiarities of the 3D electron beam printing. The mechanical effect of hardening inclusions determines a more rounded shape of wear particles, preventing wedging, and thereby increasing the stability of friction. Strengthening the metal matrix leads to reducing the number of wear particles
Effect of adhesion transfer on the surface pattern regularity in nanostructuring burnishing
In the paper the influence of friction-induced adhesion of metal to the tool on the formation of surface topography under nanostructuring burnishing was studied. A comprehensive approach, including both experimental (optical microscopy and profilometry) and theoretical (computer-aided simulation) methods was used. The results showed a direct connection between values of adhesion strength of materials in contact with the workpiece surface pattern quality caused by the tool movement. Results of the experimental and theoretical study are in good agreement and allow us to identify the reason of regular profile forming during surface burnishing
Relationship between acoustic emission and microcrack formation in single crystals of Hadfield steel
Abrasive wear is not favorable for Hadfield steel. The connection between the acoustic emission signal and th
Experimental Research Into Generation of Acoustic Emission Signals in the Process of Friction of Hadfield Steel Single Crystals
The results of experimental research into dry sliding friction of Hadfield steel single crystals involving registration of acoustic emission are presented in the paper. The images of friction surfaces of Hadfield steel single crystals and wear grooves of the counterbody surface made after completion of three serial experiments conducted under similar conditions and friction regimes are given. The relation of the acoustic emission waveform envelope to the changing friction factor is revealed. Amplitude-frequency characteristics of acoustic emission signal frames are determined on the base of Fast Fourier Transform and Short Time Fourier Transform during the run-in stage of tribounits and in the process of stable friction
Organização do tráfego de veículos com base no monitoramento ambiental da bacia aérea
Modern scientific knowledge of a problem of environmental pollution by the motor transport is based on idea of negative impact of all transport complex, and not just separate objects of transport. The problem of environmental pollution by objects of a motor transportation complex is aggravated with rapid growth of vehicular fleet. In total with insufficient development of a street road network and low level of quality of management of motor transportation streams it leads to emergence of a critical ecological situation in the cities. Along with the progressing deterioration of atmospheric air also other environmental problems connected with production of automotive vehicles, spare parts and operational materials, operation, service, storage and vehicle scrappage become aggravated.In the circumstances restriction of emissions of pollutants from motor transportation streams taking into account pollution of the air basin with stationary sources has high degree of relevance. At realization of actions of this direction also projection of quality of the air basin on the basis of environmental monitoring and imitating modeling of motor transportation streams is significant objective current.Establishment of quotas for emissions of pollutants from motor transportation streams taking into account the polluting background and achievement of the established quotas at the expense of the organization of the movement of cars is represented to one of effective ways of
permission of a problem situation. The offered way of a predetermined development of the technique of the system analysis defining the sequence of stages of carrying out the analysis and methods of their performance, uniting mathematical modeling and programming, techniques of sampling of air, the laboratory and tool analysis and statistical processing of results of an experiment.
In this regard, the way of restriction of emissions of pollutants from motor transportation streams by introduction of quotas for which realization the algorithm, the special software and a settlement and tool technique of environmental monitoring of motor transportation streams is offered is developed.El conocimiento científico moderno de un problema de contaminación ambiental por el transporte de automóviles se basa en la idea del impacto negativo de todos los complejos de transporte, y no solo de los objetos de transporte separados. El problema de la contaminación ambiental por objetos de un complejo de transporte de motor se ve agravado con el rápido crecimiento de la flota vehícular. En total, con un desarrollo insuficiente de una red vial de calles y un bajo nivel de calidad de la gestión de las rutas de transporte motor, conduce a la emergencia de una situación ecológica crítica en las ciudades. Junto con el deterioro progresivo del aire atmosférico también se agravan otros problemas ambientales relacionados con la producción de vehículos automotores, piezas de repuesto y materiales operacionales, operación, servicio, almacenamiento y chatarra de vehículos.En estas circunstancias, la restricción de las emisiones de contaminantes de las corrientes de transporte motor teniendo en cuenta la contaminación de la cuenca atmosférica con fuentes estacionarias tiene un alto grado de relevancia. En la realización de las acciones de esta dirección también la proyección de la cualidad de la balsa de aire sobre la base de la observación del medio ambiente y la imitación del modelado de los flujos del transporte a motor es la corriente objetivo significativa.El establecimiento de cuotas para las emisiones de contaminantes de los flujos de transporte
motor teniendo en cuenta el fondo contaminante y el logro de las cuotas establecidas a expensas de la organización del movimiento de automóviles está representado por una de las formas efectivas de autorización de una situación problemática. La manera de desarrollo predeterminado de la técnica del análisis del sistema define la secuencia de etapas de realización del análisis y métodos de su desempeño, uniendo el modelado y programación matemática, técnicas de muestreo de aire, el análisis de laboratorio y herramienta y el procesamiento estadístico de resultados de un experimento.
En este sentido, se desarrolla la forma de restricción de las emisiones de contaminantes de las corrientes de transporte motor mediante la introducción de cuotas para las cuales se ofrece la realización del algoritmo, el software especial y una técnica de asentamiento y herramienta de monitoreo ambiental de las corrientes de transporte motor.O conhecimento científico moderno de um problema da poluição ambiental pelo transporte motor é baseado na ideia do impacto negativo de todo o complexo de transporte, e não apenas objetos de transporte separados. O problema da poluição ambiental por objetos de um complexo de transporte motorizado é agravado com o rápido crescimento da frota de veículos. No total com o desenvolvimento insuficiente de uma rede rodoviária de rua e o baixo nível da qualidade da gestão de correntes de transporte motoras leva à emergência de uma situação ecológica crítica nas cidades. Juntamente com a deterioração progressiva do ar atmosférico, outros problemas ambientais relacionados à produção de veículos automotivos, peças sobressalentes e materiais operacionais, operação, manutenção, armazenamento e sucateamento de veículos se agravam.
Nas circunstâncias a restrição de emissões de poluentes de correntes de transporte de motor que levam em conta a poluição da bacia aérea com fontes estacionárias tem o alto grau da relevância. No momento da realização de ações desta direção também a projeção da qualidade da bacia aérea com base no monitoramento ambiental e imitando a modelagem de correntes de transporte de motor é a corrente objetiva significante.
O estabelecimento de cotas para emissões de poluentes de fluxos de transporte de motor que levam em conta o fundo poluindo e realização das cotas estabelecidas às custas da organização do movimento de carros é representado a um de modos efetivos de permissão de uma situação de problema. O caminho oferecido desenvolvimento predeterminado da técnica da análise de sistema definindo a seqüência de etapas de executar a análise e métodos de seu desempenho, unindo modelagem matemática e programação, técnicas de amostragem de ar, a análise de laboratório e ferramenta e processamento estatístico de resultados de um experimento.
Neste sentido, o caminho de restrição de emissões de poluentes de fluxos de transporte de motor pela introdução de cotas para a qual a realização o algoritmo, o software especial e uma técnica de ajuste e instrumento de monitorização ambiental de fluxos de transporte de motor se oferece desenvolve-se
The Interrelation Between Hardiness and Prognostic Potential of Students of Higher Education Institutions
The paper presents the results of an empirical study of specific features and the relationship between hardiness of students and prognostic potential of their personality. The methods of research comprised: theoretical analysis, empirical research (testing), qualitative analysis of the obtained data, mathematical and statistical data processing (SPSS Statistics, Excel). It has been found that students with a high level of prognostic potential development are distinguished by pronounced personality traits typical of hardy people. The authors have proved in the paper that the prognostic potential of students is a holistic system of personality resources, which is based on specific features of thinking and building a secondary image. There are criteria and development levels of the prognostic potential among students: an internal criterion (features of thinking and building secondary images) and an external criterion (the effectiveness of forecasting activities, the conformity of the stages of prognostic activity with the reference model). The prognostic potential is interconnected with personal and professional characteristics of students (features of the intellectual, communicative, emotional-volitional and motivation spheres). There are significant differences between students with different levels of development of prognostic potential according to the main personal and professional features. The correlation analysis of the data gave the following interrelations: there is a direct interrelationship between the level of development of prognostic potential and emotional stability of students; between the level of development of prognostic potential and such motives for studying at a university as professional and educational-cognitive motives; between the level of development of prognostic potential and the features of self-regulation. On the basis of the results of an empirical study, the authors designed a program for the prognostic potential development of students which includes active teaching methods, lectures, and trainings
Comportamiento destructivo de una persona en retrospectiva histórica: factores, diagnóstico y prevención
In conditions of the current development of society which is characterized by mounting social, economic and political crises, the problem of destructive behavior of an individual acquires special significance and topicality. The paper presents the results of a theoretical and methodological analysis of this problem in foreign and domestic literature in several areas: analysis of the attitude of society towards destructive behavior in its historical aspect; philosophical and theological approach; sociological and demographic areas in the study of destructive behavior, biological and biochemical; genetic approaches; psychological and socio-psychological aspects in the study of destructive behavior of a person. In view of the analysis of various approaches and areas in the study of destructive behavior, the conclusions have been drawn that destructive behavior is represented as a complex phenomenon, caused by biological factors (genetic predisposition, constitutional features of the body structure, the use of psychoactive substances, etc.), social (economic and social crises ), psychopathological (connection with mental disorders), psychological (especially the system of needs and motives of activity), socio-psychological (the impact of socio-psychological maladaptation and characteristics of the values and meaning sphere of an individual) plans. These factors are interconnected and each of them has its own specific role in the complex of destructive behavior, and therefore it is impossible to obtain a holistic view of the phenomenon under consideration taken separately from the entire system of interconnected components.En las condiciones del desarrollo actual de la sociedad, que se caracteriza por el aumento de las crisis sociales, económicas y políticas, el problema del comportamiento destructivo de un individuo adquiere un significado especial y actualidad. El artículo presenta los resultados de un análisis teórico y metodológico de este problema en la literatura extranjera y nacional en varias áreas: análisis de la actitud de la sociedad hacia el comportamiento destructivo en su aspecto histórico; enfoque filosófico y teológico; áreas sociológicas y demográficas en el estudio del comportamiento destructivo, biológico y bioquímico; enfoques genéticos; Aspectos psicológicos y socio-psicológicos en el estudio del comportamiento destructivo de una persona. En vista del análisis de varios enfoques y áreas en el estudio del comportamiento destructivo, se ha llegado a la conclusión de que el comportamiento destructivo se representa como un fenómeno complejo, causado por factores biológicos (predisposición genética, características constitucionales de la estructura del cuerpo, el uso de sustancias psicoactivas, etc.), sociales (crisis económicas y sociales), psicopatológicas (conexión con trastornos mentales), psicológicas (especialmente el sistema de necesidades y motivos de actividad), sociopsicológicas (el impacto de la mala adaptación sociopsicológica y las características de los valores y la esfera de significado de un individuo) planes. Estos factores están interconectados y cada uno de ellos tiene su propio papel específico en el complejo del comportamiento destructivo y, por lo tanto, es imposible obtener una visión holística del fenómeno en consideración tomado por separado del sistema completo de componentes interconectados
- …