Investigation of the Ni3Al-Fe alloys by resistivity measurements and differential thermal analysis

A series of iron-doped Ni3Al ternary alloys is investigated by resistivity measurements and differential thermal analysis. Temperatures of phase transformations and disordering onset are determined. A hysteresis phenomenon is observed in the liquid state in polytherms of resistivity upon heating the alloy under study to the critical temperature. © 2013 Allerton Press, Inc

The choice of analytes’ powder-carrier for preparing calibration samples when analyzing welding fumes using X-ray fluorescence

Введение. Рассмотрены процессы образования твердой составляющей сварочных аэрозолей (ТССА); показано, что частицы ТССА отличаются фазовым и химическим составом, дисперсностью в зависимости от свариваемых материалов и условий сварки; основными фазами является магнетит Fe₃O₄ и железомарганцевая шпинель MnFe₂O₄. Проблема. Определение градуировочных характеристик недеструктивных методик рентгенофлуоресцентного анализа (РФА) и проверка правильности методик количественного химического анализа ТССА осложнены отсутствием стандартных образцов. Создание аттестованных смесей, адекватных реальным пробам ТССА, собранным на фильтр, затруднено из-за сложности их физико-химических свойств. Эксперимент. Приготовлены синтетические образцы в виде тонкой органической пленки, содержащей порошковые соединения элементов, контролируемых в ТССА. Проведены исследования по выбору порошкового носителя аналитов для создания аттестованных смесей. Оценено максимальное значение размера зерен порошка, когда эффектом микроабсорбционной неоднородности можно пренебречь на фоне случайной погрешности изготовления пленочных аттестованных смесей. Экспериментально доказано, что в качестве порошка-носителя аналитов при создании градуировочных образцов для недеструктивных методик РФА проб ТССА допустимо применять любые соединения аналитов, если размер их частиц менее 4 мкм. Результаты. Создан комплект пленочных аттестованных смесей, которые можно рекомендовать в качестве градуировочных образцов для недеструктивных методик РФА; погрешность их изготовления характеризуется коэффициентом вариации 5-6 %.The processes of forming the solid component of welding fumes (SCWF) are considered; the particles of SCWF are shown to differ in phase and chemical composition, and dispersion depending on welding materials and welding conditions; the magnetite Fe₃O₄ and the iron-manganese spinel MnFe₂O₄ are the main phases. The determination of calibration characteristics of non-destructive techniques and the validation of the techniques for quantitative chemical analysis of SCWF are complicated by the lack of certified reference materials. The development of certified mixtures, appropriate to real samples of SCWF collected on a filter, is difficult because of the complexity of their physical and chemical properties. The synthetic samples were prepared in the form of an organic thin film containing the powder compounds of elements controlled in the SCWF. The studies were conducted to choose the powder-carrier of analytes for developing the certified mixtures. The maximum size value of powder grains were estimated when the effect of micro absorption heterogeneity can be neglected on the background of random error in preparing film certified mixtures. It is experimentally proven that any analyte compounds are suitable for use as a powder-carrier of analytes in developing the calibration samples for the non-destructive techniques of X-ray fluorescence analysis (XRF) of SCWF samples if their particle sizes are less than 4 microns. A set of film certified mixtures was developed, which can be recommended as the calibration samples for the non-destructive XRF techniques; the error in their preparation is characterized by the variation coefficient of 5-6 %

Low-temperature spin relaxation in n-type GaAs

Low-temperature electron spin relaxation is studied by the optical orientation method in bulk n-GaAs with donor concentrations from 10^14 cm^{-3} to 5x10^17 cm^{-3}. A peculiarity related to the metal-to-insulator transition (MIT) is observed in the dependence of the spin lifetime on doping near n_D = 2x10^16 cm^{-3}. In the metallic phase, spin relaxation is governed by the Dyakonov-Perel mechanism, while in the insulator phase it is due to anisotropic exchange interaction and hyperfine interactio

Essential Characteristics of Media Political Discourse

Introduction. The article presents an overview of the constitutive features of media political discourse. The aim of the article is to determine the essential parameters of modern Englishlanguage media-political discourse. The main components of this type of discourse, its axiological structure are considered. Special attention is paid to the ideological and manipulative nature of media political discourse. The relevance of the study is conditioned by the necessity of singling out media political discourse as one of the sections of discourse theory through the meticulous study of its system-forming features.Methodology and sources. As a methodological basis, the article uses some ideas of the functional approach to discourse analysis, in particular, critical discourse analysis, as well as cognitive linguistics, media discourse, medialinguistics, multimodal approach to the study of discourse. The main method is an analytical scientific review of Russian and foreign works on discourse theory.Results and discussion. According to the results of the review, the main components of media political discourse are political topics, political actors, political language, and, mainly, mass media that mediate communication within the framework of MPD. The fundamental characteristics of media political discourse include ideology, manipulativeness, persuasiveness, emotionality, polycodicity, informativeness, dynamism, and theatricality. Virtual media-political discourse, as well as Internet discourse in general, is characterized by hybridity, stylistic heterogeneity, creolization, multichannel and dialogicality, and involves remote interactive and immersive communication of virtual interlocutors. A higher level of actualization, timeliness and informativeness of online media-political discourse compared to traditional media is evident. New media supplement traditional media tasks with new functions. The axiological halo of the text, which means the whole set of values presented in the text, has a decisive impact on the interpretation of the author's ideological position and contributes to the strengthening of the media political text's suggestiveness. Based on the definition of such features of media political discourse as polycode and multilevel, it seems most effective to consider this type of discourse from the position of multimodality.Conclusion. The main function of media political discourse can be considered the construction of collective political reality in this type of discourse. Media political discourse is a construct that has constitutive power and participates in the construction of social reality. The media political picture of the world is constructed through the broadcasting of certain images, meanings, ideological attitudes, values and political preferences

Cognitive-Discursive Study of Migration Discourse (Based on English-Language Media Texts)

Introduction. This article is a fragment of a study on migration discourse. The migration discourse uses a persuasive strategy implemented by means of evaluation information strategy. Evaluation information strategy is carried out mainly through persuasive tactics, which are introduced into the text thanks to the cognitive metaphor. Metaphor allows to compare economic and political concepts with simple and visible images. The construction of conceptual integration schemes makes it possible to track the process of forming a particular image and, consequently, implementing a persuasive strategy in a media text. In modern research, the mechanism of intertextuality can be analyzed in terms of conceptual integration, since intertextual references make a connection with background knowledge.Methodology and sources. The material for the study was articles in English published in American periodicals: https://www.nytimes.com, https://www.washingtonpost.com, as well as on the website https://edition.cnn.com. At the first stage of the study, articles were considered at the text level with the identification of lexical, syntactic and stylistic aspects of the functioning of the discourse. At the second stage (discourse as a discursive practice), examples of intertextuality were investigated, including the depth layer of intertext – cognitive one. The essence of the third stage of work with media texts was the search for interconnection and mutual influence of discourse and social practice. At this stage of the study, the focus of attention was shifted from the media text itself to the socio-political situation in the context of which this text was generated. At each level, an attempt was made to determine which of the means contribute to the realization of the persuasive strategy in the media text and how it is carried out.Results and discussion. The phenomenon of migration is examined in media texts as objectively as possible, both the pros and cons of the migration process are given. The evaluation strategy and related tactics are mainly aimed at describing the actions of politicians. Discrediting tactics directed against Trump are adjacent to Biden’s positive representation tactics and, thus, we-they polarization (we-Biden, they-Trump) through linguistic means, as well as cognitive metaphor is performed. In the articles reviewed, lexemes from the migration and militaristic discourse are often found, and vocabulary describing the events of the coronavirus pandemic period and the accompanying economic crisis are widespread. From the viewpoint of intertextual references, a high percentage of numerals and proper names, which give the impression of the authority of the material, might be of particular interest. The cognitive layer of intertext is widely represented by a conceptual metaphor. Some metaphors discussed in the article participate in the representation of migration and the migration crisis, other metaphors contribute to understanding political and economical processes and phenomena directly or indirectly related to migration. Metaphor-disease, metaphor-natural phenomenon and commoditymaterial metaphor were the most common in the studied body of texts.Conclusion. The migration discourse studied is explicitly related to politics, to issues of power and influence. The persuasive strategy contributes to the construction of images of politicians: Trump is introduced through the mistakes that he made as president of the United States, as well as his inadequate and sometimes cruel actions against migrants, Biden is represented through social problems that he needs to solve performing the role of the president elect. Obviously, the migration issue is a key factor, a test task, which Biden will have to work on immediately after coming to power

Two-body quantum mechanical problem on spheres

The quantum mechanical two-body problem with a central interaction on the sphere ${\bf S}^{n}$ is considered. Using recent results in representation theory an ordinary differential equation for some energy levels is found. For several interactive potentials these energy levels are calculated in explicit form.Comment: 41 pages, no figures, typos corrected; appendix D was adde

Pragmastilistic Analysis of Migration Discourse (Based on Speeches by British Politicians)

Introduction. The present study examines the pragmastilistic potential of migration discourse based on the speeches of modern British politicians. The relevance of the chosen topic lies in the acute social specifics of migration discourse and its manipulative component. In today’s world, migration processes have become global and their impact on the development of the host culture is becoming increasingly evident. There is still no established strategy for the integration of migrants into the new society, which creates a conflict environment and determines the hostility of the indigenous population towards migrants. Migration discourse as one of the directions of policy discourse becomes an effective tool for managing public opinion. Various persuasive tactics are incorporated in the speech of politicians using linguistic means, the use of which in the British migration discourse is considered in this article.Methodology and sources. The key tasks of the study are to identify specific discursive tactics, by means of which the persuasive strategy is implemented in the British migration discourse, and to analyze the stylistic techniques used to design the discovered tactics. During the study, pragmastilistic analysis was used, the application of which involves referring to the following methods of linguistic research: the method of continuous sampling, quantitative, descriptive and comparative methods, the method of stylistic analysis, discursive analysis. The material of the study was the speeches of modern British politicians from 2004 to 2021. Results and discussion. The analysis of migration discourse based on the texts of speeches by modern British politicians allows to talk about the stylistic saturation of the material and the main means of expressiveness used in the framework of the discourse under consideration. The main tactic of opponents of free migration is the comparison of “good/bad” migrants, which is actualized using antithesis. As for the lexical stylistic means, the use of the epithet should be specified, which is also a way of actualizing opposition tactics. Thus, this tactic is implemented both at the lexical and syntactic level. Similar tactics are also relevant in the framework of pro-migration rhetoric, namely, when comparing the local elite and the visiting population, which performs all the work necessary for the functioning of society. In most cases the main stylistic technique for tactics actualization is antithesis (or the convergence of antithesis and epithet). Proponents of pro-migration policies also use metaphor (tactics for describing the political process) and syntactic parallelism (tactics for describing the benefits of migration). Finally, the most common tactic inherent in both poles of migration discourse is the tactic of generalization. It consists in equating the speaker with his audience, their “fusion”, and is most often actualized using hyperbola.Conclusion. Migration discourse is characterized by an ideological orientation, which is actualized using certain speech techniques, tactics and strategies. Migration discourse, as a multifaceted entity, can also serve to harmonize social life by facilitating the integration of migrants into the host culture. Migration discourse is a powerful ideological weapon that can be used both to contribute to integration and to incite ethnic hatred. Stylistic tools play a key role in the implementation of a persuasive strategy, which is actively used both in migration and in political discourse in general. The main tactics of the migration discourse of modern British politicians are opposition and generalization, used both in pro- and anti-migration rhetoric