This work combines experimental and numerical (computational fluid dynamics) data to better understand the kinetics of the dispersion of graphite nanoplates in a polypropylene melt, using a mixing device that consists of a series of stacked rings with an equal outer diameter and alternating larger and smaller inner diameters, thereby creating a series of converging/diverging flows. Numerical simulation of the flow assuming both inelastic and viscoelastic responses predicted the velocity, streamlines, flow type and shear and normal stress fields for the mixer. Experimental and computed data were combined to determine the trade-off between the local degree of dispersion of the PP/GnP nanocomposite, measured as area ratio, and the absolute average value of the hydrodynamic stresses multiplied by the local cumulative residence time. A strong quasi-linear relationship between the evolution of dispersion measured experimentally and the computational data was obtained. Theory was used to interpret experimental data, and the results obtained confirmed the hypotheses previously put forward by various authors that the dispersion of solid agglomerates requires not only sufficiently high hydrodynamic stresses, but also that these act during sufficient time. Based on these considerations, it was estimated that the cohesive strength of the GnP agglomerates is in the range of 5–50 kPa.
For several decades the problem of prevention and correction of posture disorders in primary school children has not lost its relevance. Statistics show that 68-94 % of primary school students have posture disorders. A special place in the classification of posture disorders is occupied by a scoliotic posture. Such a statement indicates that health improving physical education does not fully solve the tasks assigned to it. Analysis of literature sources allowed us to establish two main reasons for the low effectiveness of prevention and correction of scoliotic posture in primary school children. The first reason relates to the low effectiveness of early diagnosis scoliotic posture, and the second reason is low overage of the aspects of the problem, revealing the model of periodization of fitness training with the children in the theory and practice of physical culture. The results of previous studies have allowed us to suggest ways to improve the effectiveness of prevention and correction of scoliotic posture in primary school children, namely: to expand the range of traditional methods of early diagnosis of scoliotic posture through motor and postural diagnostics; to use a nonlinear model of periodization of physical activity to create optimal conditions for leveling muscle imbalance and the formation of rational motor automatisms and patterns in the context of health training.
Научно-теоретический журнал «Ученые записки», № 2(108) -2014 год 148 ЗАКЛЮЧЕНИЕ Создание безопасной образовательной среды -основа гуманизации образования, а сама безопасность -фактор-детерминант его (образования) качества, поэтому диагностика безопасности образовательной среды -составляющая мониторинга качества образования.Работа выполнена при финансовой поддержке Российского гуманитарного научного фонда № 13-06-00350 от 13.06.2013 по теме "Мониторинг качества непрерывного образования".
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