Phenomenological coefficients in solid-state diffusion: an Introduction

In this review, which is intended as an introduction to the subject, we introduce the phenomenological transport coefficients in solid-state diffusion and discuss their structure and physical meaning. Next, we discuss the Darken, the Manning, the Moleko, Allnatt and Allnatt and the Heumann expressions which relate the phenomenological coefficients to the (measurable) tracer diffusion coefficients. Finally, we discuss the relationships (sum-rules) among the phenomenological coefficients themselves in randomly mixed systems and note their applicability for simplifying collective diffusion problems

Carbon Interstitial Diffusion in gamma-Fe

n this paper, we employ a four-frequency model for carbon diffusion in austenite where interstitials can diffuse either as isolated species or pairs. We make use of the Okamura and Allnatt formalism that has recently been shown to be near exact. The general finding of a previous analysis of McKee is confirmed: the increase of both tracer and chemical carbon diffusion coefficients with carbon composition at 1000°C is largely a result of a much higher rate of rotation of an interstitial pair compared with isolated interstitials. However, we find that the carbon atoms move almost two times faster as a rotating pair than found originally by McKee

Recent progress in the simulation of diffusion associated with hollow and Bi-metallic nanoparticles

In this paper, we review the recent understanding gained by kinetic Monte Carlo and molecular dynamics simulation and related theory of the diffusion processes involved in 1) the formation and later shrinkage of hollow nanoparticles and 2) the formation of segregated bi-metallic nanoparticles

Computer simulation of the formation of hollow nanocrystals

Experiments on the formation of hollow nanocrystals of cobalt sulphide by way of the Kirkendall effect have been reported recently by Yin et al. We perform a set of Monte Carlo simulations of the process to explore the phenomenon

Effect of zinc doping on electrical properties of LaAlO3 perovskite

New solid solution with the general formula of LaAl1-xZnxO3-1/2x was prepared by a solid-state reaction route. According to XRD, the crystal structure of LaAlO3 is rhombohedral, while the solid solution possesses cubic symmetry. Homogeneity region of the solid solution LaAl1-xZnxO3-1/2x was narrow and limited to the maximum concentration of 5 mol. %. Computer simulations using crystalochemistry and density functional theory approaches showed that LaAlO3 has high energy barriers for O2–-ion transport (2.79 eV). These results are in good agreement with the low values of electrical conductivity obtained experimentally. The electrical conductivity of LaAl1-xZnxO3-1/2x was measured by impedance spectroscopy in the temperature range of 200–1000 °C. The partial substitution of Al3+ by Zn2+ was found to increase the electrical conductivity by ~2 order of magnitude. The electrical conductivity of doped phase LaAl0.95Zn0.05O2.975 as a function of oxygen partial pressure was measured, and the partial contributions (oxygen-ionic and electronic) were determined. It was found that the sample has mixed ionic and p-type electronic conductivity, while the electronic contribution increases with the rise of the temperature

Tecnologias e dispositivos de microondas que separam a pele da pele de coelho

The purpose of this work is the development of microwave technology and de-vices separating fur from rabbit skins in a continuous mode at reduced operating costs. They developed the method for the action of the ultrahigh frequency electro-magnetic field (UFEF), which provides the reduction of fur fiber holding power in the meat fabric of rabbit skins with simultaneous combing and gathering. They calcu-lated the mathematical dependences describing the dynamics of multicomponent raw material heating with the change of dielectric and physicomechanical parameters in the process of UFEF. They calculated and visualized the electromagnetic field distri-butions in the developed resonators, on the basis of which they substantiated the ef-fective parameters of the electrodynamic system: the maximum property, the quality of resonators and the electric field strength. They substantiated the complex of struc-tural and technological parameters of devices with new structural design of working chambers by a multi-criteria evaluation of the technological process for the separation of fur from rabbit skin. They manufactured and tested the microwave device under production conditions for the separation of fur from rabbit skin, and adjusted the op-erating modes, which allow to reduce operating costs. They evaluated the technical and economic efficiency of microwave technology introduction for the processing of fur and the devices for rabbit farms; they developed practical recommendations for the operation of microwave units to separate fur from rabbit skins.El propósito de este trabajo es el desarrollo de la tecnología de microondas y los dispositivos que separan la piel de los cueros de conejo en un modo continuo a costos operativos reducidos. Desarrollaron el método para la acción del campo electromagnético de frecuencia ultraalta (UFEF), que proporciona la reducción del poder de retención de la fibra de la piel en el tejido de carne de la piel de conejo con el peinado y la recolección simultáneos. Calcularon las dependencias matemáticas que describen la dinámica del calentamiento de materias primas de componentes múltiples con el cambio de los parámetros dieléctricos y fisicomecánicos en el proceso de la UFEF. Calcularon y visualizaron las distribuciones del campo electromagnético en los resonadores desarrollados, sobre la base de los cuales fundamentaron los parámetros efectivos del sistema electrodinámico: la propiedad máxima, la calidad de los resonadores y la intensidad del campo eléctrico. Ellos sustentaron el complejo de parámetros estructurales y tecnológicos de los dispositivos con un nuevo diseño estructural de las cámaras de trabajo mediante una evaluación de múltiples criterios del proceso tecnológico para la separación de la piel del cuero del conejo.  Fabricaron y probaron el dispositivo de microondas en condiciones de producción para la separación de la piel de la piel de conejo, y ajustaron los modos de operación, lo que permite reducir los costos operativos. Evaluaron la eficiencia técnica y económica de la introducción de la tecnología de microondas para el procesamiento de pieles y los dispositivos para granjas de conejos; desarrollaron recomendaciones prácticas para el uncionamiento de las unidades de microondas para separar las pieles de los cueros de conejo.O objetivo deste trabalho é o desenvolvimento de tecnologia e dispositivos que separam a pele de peles de coelho em um modo contínuo a custos operacionais reduzidos microondas. Eles desenvolveram o método para a acção do campo electromagnético de alta frequência ultra-(UFEF), que fornece pele de coelho carne tecido de pele para retenção de fibras de energia reduzido com cabelo e recolha simultânea. Calcularam as dependências matemático para descrever a dinâmica do aquecimento materiais multicomponentes com a mudança de dieltricos e parâmetros fisicomecánicos no processo de UFEF. Eles calculado e visualizado as distribuições de campo eletromagnético em ressonadores desenvolvidos, com base na qual fundamentar os parâmetros reais do sistema electrodynamic: a propriedade máximo, a qualidade dos ressonadores e intensidade do campo elétrico. Eles sustentadas parâmetros estruturais e tecnológicas complexas dos dispositivos com um novo design estrutural das câmaras de trabalho através de uma avaliação multi-critérios do processo tecnológico para a separação de couro pele de coelho. Eles fabricado e testado o dispositivo de micro-ondas, sob condições de produção para a separação da pele da pele de coelho, e modos de operação ajustados, reduzindo assim os custos operacionais. Eles avaliaram a eficiência técnica e econômica da introdução de tecnologia de microondas para o processamento de dispositivos fazendas de peles e de coelho; desenvolveu recomendações práticas para a operação de unidades de microondas para separar peles de peles de coelho

SEMANTIC FEATURES OF THE PHRASEOLOGICAL UNITS WITH THE COMPONENT LIGHT THE WITHIN ARTISTIC DISCOURSE

Purpose: To conduct lexical and semantic analysis on the concept light in the artistic discourse of postmodern fiction. Methodology: In this research, comparative method, search for synonyms, continuous sampling and seminal analysis are used. Main Findings: As a result, it becomes obvious that the boundaries of the artistic concepts are extremely blurred and much wider than the boundaries of the corresponding non-artistic concepts. In conclusion, the concept light is frequently used in English artistic discourses, i.e. significant in the culture, and a special status in the semantic space of the concept light has the meaning of knowledge and information. Applications: The study results can be used by students and universities. Novelty/Originality: In this research, a model of the semantic features of the phraseological units with the component light is presented in a comprehensive and complete manner