416 research outputs found
Isophots of Zodiacal Light and Its Terrestrial Component
Isophotes of zodiacal light and its terrestrial component due to interplanetary dust in vicinity of earth-moon syste
Analysis of the problems of formation of calligraphic skills in primary school pupils
The article presents the results of a study of calligraphic writing skills in primary school pupils of the general education school and analyzes problems with the acquisition of these skills.В статье представлены результаты исследования каллиграфического навыка письма у обучающихся начальных классов общеобразовательной школы, проведен анализ трудностей овладения данным навыком
Thermal Raman study of Li4Ti5O12 and discussion about the number of its characteristic bands
Lithium battery industry is booming, and this fast growth should be supported
by developing industry friendly tools to control the quality of positive and
negative electrode materials. Raman spectroscopy was shown to be a cost
effective and sensitive instrument to study defects and heterogeneities in
lithium titanate, popular negative electrode material for high power
applications, but there are still some points to be clarified. This work
presents a detailed thermal Raman study for lithium titanate and discusses the
difference of the number of predicted and experimentally observed Raman-active
bands. The low temperature study and the analysis of thermal shifts of bands
positions during heating let us to conclude about advantages of the proposed
approach with surplus bands and recommend using shifts of major band to
estimate the sample heating
Lattice dynamics of HoGa3(BO3)4 and HoFe3(BO3)4 crystals
This work is financially supported by the Russian Foundation for Basic Research № 18-02-00754
Resistance of seedlings of native and alien species of the genus Bidens (Asteraceae) from different geographic populations to the action of heavy metals
One approach to assessing the competitiveness of invasive species is a comparative analysis of the morphological, physiological, and reproductive traits of this species with native species of the same genus. The invasive species Bidens frondosa L. from the Asteraceae family, included in the list of the 50 most common and most aggressive invasive species in Europe, occupies the same ecological niche as the native species B. tripartita L., and displaces it from natural habitats. There is an obvious and growing interest in the sustainability of B. tripartita and B. frondosa in extreme conditions of existence, one of which is the action of heavy metals. Our research was performed in laboratory conditions with seedlings that developed from seeds collected from populations of the Upper and Middle Volga region. The seeds were germinated in Ni2+ and Cu2+ solutions at various concentrations. At the end of the experiment, morphometric parameters were measured and the index of tolerance was determined. Seedlings from different populations under the influence of nickel ions developed at concentrations of 1–50 mg/l, under the influence of copper ions – at 1–100 mg/l. The nickel and copper ions had the greatest toxic effect on the growth and development of the root system – at 25 mg/l and above, the main root was completely necrotic, while the action of copper ions simultaneously increased the number of adventitious roots. The tolerance index (“root test”) under the action of nickel ions was higher among the seedlings from the population of the Middle Volga region, while under the action of copper ions there were no significant differences among the seedlings from different populations. However, it decreased with the action of both heavy metals at a concentration of 10 mg/l. High concentrations of both metals significantly reduced the length of the hypocotyl, cotyledon, and the true leaf. It was also found that copper ions are more toxic for the root system (main root and adventitious roots), nickel ions – for above-ground organs (hypocotyl, cotyledons, and true leaves). We noted differences between the populations to the action of nickel and copper. From the population of the Upper Volga region, the seedlings of B. frondosa were more stable. For seedlings from the population of the Middle Volga, a smaller toxic effect was confirmed for B. tripartita. It can be assumed that the resistance of B. frondosa to the action of heavy metals as a stress factor in the Upper Volga region is one of the reasons for the suppression of B. tripartita by the invasive species
Cubic to cubic phase transition in (NH4)3SnF7 ferroelastic crystal – Raman scattering study
This work was supported by Russian Foundation for Basic Research (Grant N 17-02-00920)
Russian University Teachers’ Ethical Culture Regulation
Based on a review of publications of Russian and foreign researchers, the authors highlight the most significant topics on the deontology of university life. The article presents the results of an analysis of the texts of ethical codes of some leading universities in Russia (National Research University Higher School of Economics, Moscow State University, St. Petersburg State University, Kazan Federal University, Ural Federal University), as well as the results of an online survey (N = 297) of teachers of these universities. The survey was conducted to study the attitude of the teaching staff towards the tools for standardizing the moral culture of universities and the implementation of the values enshrined in the ethical standards of universities and ideals of academic community. Conclusions are made about the ethical attitudes of teachers and the effectiveness of moral regulation, as well as proposals for improving the ethical codes of universities are made
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