A detailed study of the effect of reaction temperature, time, and cocatalyst composition on the ethylene polymerization performance of 2-[1-(2,6-dibenzhydryl-4-chlorophenylimino)­ethyl]-6-(1-mesityliminoethyl)­pyridyliron dichloride (1) is reported. In the presence of modified methylaluminoxane (MMAO), 1 behaves like a highly active, “multisite-like” ethylene polymerization catalyst, with the resulting polyethylenes having time-dependent bimodal-like molecular-weight distributions and featuring saturated (n-propyl- and i-butyl-terminated) chain ends. To readily distinguish between bimodal and bimodal-like molecular-weight distributions, we have proposed the use of the dN f/(d log M) – log M representation further to the mainstream dW f/(d log M) – log M one. The consensus mechanism of chain transfer and chain-end formation in the presence of MMAO has been proposed, which explains the composition and amount of terminal alkyl groups in the polymer, and the apparent “multisite-like” nature of the iron catalyst. A comparison between the catalytic behaviors of the “multisite-like” 1/MMAO catalyst system and the truly multisite catalyst system based on Brookhart’s symmetrical bis­(imino)­pyridine iron catalyst 2 is given.

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The introduction of second generation standards is a significant innovation for the initial stage of education, the foundation of which is the achievement of qualitatively new educational results that affect the development of a harmonious personality. At the primary school age, the formation of educational activity as the leading one takes place, therefore, in our study, a special place is given to self-esteem. The article analyzes various approaches related to the study of self-esteem in domestic and foreign psychology and pedagogy, which made it possible to determine the basis of the experimental part of the study. The purpose of the article was to use the analysis of psychological, pedagogical and methodological literature to conduct a study of self-assessment in children of primary school age on the subjects "Russian language" and "Literary reading"; development and testing of a set of tasks and exercises aimed at forming self-esteem of younger students in educational activities. The empirical study involved 80 children aged 9-10 years from schools in Nizhny Novgorod and the Nizhny Novgorod region. The results of the ascertaining stage of the study showed that the majority of third graders have an overestimated (60%) or underestimated self-esteem (24%), 16% of students correspond to adequate self-esteem. The formative stage was realized in the lessons of the Russian language and literary reading. The complex considered techniques, exercises and tasks used in educational activities to form self-esteem in younger students. The effectiveness of the shaping influences was confirmed by the results of the control stage.

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Introduction. The implementation of competency-based approach in the university requires the development of evaluation tools, which contribute to assessing the formation of professional competencies. Diagnostic materials should reflect the real school practice, the experience of teachers, as well as the existing methodological problems and difficulties when organising the activities of teachers.The aim of the research was to assess the effectiveness of case-note as an assessment tool, which allows us to judge the methodological competency both of a university graduate and a practising teacher.Methodology and research methods. The research was carried out employing activity and competency-based approaches related to the application of methods of modelling and comparative analysis.Results and scientific novelty. As a means of a diagnostic methodology, a case-designed lesson plan presented by the authors combines the characteristics of a traditional lesson plan and a case-structured assignment. The features of the case-designed lesson plan and its content specificity were thoroughly analysed; specific examples were provided.The approbation of methodology was carried out among the students enrolled in “Psychology and Pedagogy of Primary Education” direction and primary school teachers, who attended advanced training courses. The results of performing tasks in Mathematics case-designed lesson plans were analysed by different categories of examinees, who participated in the research. The indicators determined in the groups of teachers were ranged according to the qualification category and work experience of teachers. Problems, typical challenges and mistakes made were commented on. On the basis of comparing the data obtained in groups of teachers and students, it was concluded that a case-designed lesson plan can serve as an effective tool for diagnosing the methodological readiness of future teachers and practising teachers for professional work. The recommendations on drafting case-designed lesson plans were proposed.Practical significance. The materials of the research can be useful for university teacher-methodologists when developing tools for diagnosing graduates’ readiness for professional pedagogical activity. Case-designed lesson plans can be used as a didactic material in the course of practical training of university students or further training of teachers.