383 research outputs found
Identification of weeds from the cabbage family (Brassicaceae) found in the agrocenoses of the Russian Federation
Members of the Brassicaceae family are of great significance as weeds and invasive plants; they are one of the leading families of the alien fraction in the segetal floras of various regions of Russia. Among the cruciferous weeds growing over Russia, there are many species that are wild relatives to cultivated plants. Some cultivated species grow outside of their cultivation areas as ruderal and segetal plants. Among the cruciferous plants growing in Russia, 28 species out of 19 genera are regulated as harmful organisms in 33 different countries. Most of the species from this list are widespread weeds in Russia.To establish the presence of Brassicaceae species in Russian agrocenoses, we analyzed published sources, herbarium materials stored in the Russian leading herbaria, and materials collected by the authors during field explorations in 2017–2022 in 19 subject entities of the Russian Federation. Identification of cruciferous plants is often a rather difficult task, so the goal of this work was to develop a convenient identification key that would make in possible to identify weeds of this family found in Russian agrocenoses. Most of the available keys are designed for fruit-bearing specimens of cruciferous plants. For phytosanitary purposes, it is important to identify plants prior to their fruiting period. Therefore, we additionally used the characters of flowering plants (including their vegetative organs) enabling us to identify cruciferous plants at the flowering stage. Based on such features, a table was made, which included all weedy species of Brassicaceae found in agrocenoses within Russia (83 species in total). On the basis of this table, an identification key was produced for the identification of genera and some species of weedy cruciferous plants. Afterwards, fractional species-specific keys were made for the genera containing species controllable in importing countries
Extraction processing of concentrated solutions of uranyl nitrate with high impurities content
Process flowsheet of recycling uranium concentrated solutions with its purification from insoluble impurities of iron, silicon, molybdenum, calcium oxides and hydroxides and soluble impurities with application of centrifugal extractors cascade has been developed and suggested for commercial introduction. The process was carried out at extractant saturation (30 % tributyl phosphate in hydrocarbon diluent) in extraction assembly lower than a limiting level (85...95 g/l) and in wash assembly - at limiting saturation (up to 120 g/l). As a result the waste uranium content in water-tail solutions 0,01...0,04 g/l and minimal content of impurities in re-extractors is provide
Asymmetric Faraday Effect in a Magnetophotonic Crystal
It is widely known that the magneto-optical Faraday effect is linear in
magnetization and therefore the Faraday angles for the states with opposite
magnetizations are of opposite sign but equal in modulus. Here we
experimentally study propagation of light through a one-dimensional all-garnet
magnetophotonic crystal to demonstrate an asymmetric Faraday effect (AFE) for
which Faraday angles for opposite magnetic states differ not only in sign but
in the absolute value as well. AFE appears in the vicinity of the cavity
resonance for an oblique incidence of light which plane of polarization is
inclined to the incidence plane. Under proper incidence and polarization angles
the magnitude of AFE could be very large reaching 30% of the absolute value of
the Faraday effect. The effect originates from the difference in Q-factors for
p- and s- polarized cavity modes that breaks the symmetry between the two
opposite directions of polarization rotation. The discovered AFE is of prime
importance for nanoscale magnonics and optomagnetism.Comment: Supplementary information provided after the main tex
Projectile fragmentation at Fermi energies with transport simulations
Projectile fragmentation at Fermi energies is an important method to produce radioactive beams for the study of isospin asymmetric nuclear matter. Fragmentation is usually parametrized successfully by empirical phase space models. In this contribution we apply a microscopical method, semiclassical transport theory, to study in detail the reaction mechanism of the fragmentation process. We apply it to experimental data of 18O on 181Ta at E/A = 35 MeV measured in Dubna. We calculate consistently the excitation energy of the primary fragments and take into account their decay by a statistical model. It is found that the dissipative part of the fragment spectra is well described by transport theory. However, there are in addition important direct and collective contributions
A CLUSTERING APPROACH IN THE UrQMD TRANSPORT MODEL FOR NUCLEAR COLLISIONS AT RELATIVISTIC ENERGIES
A method for cluster recognition from nucleon distributions generated in calculations of relativistic collisions of light particles (protons, α-particles) with nuclei in the framework of the UrQMD model is proposed. The excitation energy of the clusters which is necessary to take into account for the de-excitation of the calculated fragments was estimated from empirical considerations. The approach was applied to calculate mass distributions of fragments in p + Fe collisions for different proton energies and showed a good correspondence to experimental results. The software implementation of the clustering method and a visualization of cluster formation substantially facilitate applications of the proposed method
The research of uranium monoxide-oxide dissolution process in nitric acid
The kinetics of concentrates of uranium monoxide-oxide dissolution process by nitric acid solutions of 5...9 mole/l in the range of 11...90 °C has been studied. It is stated that initial nitric acid concentration increasing results in some uranium dissolution degree increasing only at the first process stage. Temperature increasing significantly raises uranium dissolution degree at the first stage as well. Uranium dissolution degree increases for all studied temperatures with increasing of the process period. The main feature of the studied process is that while dissolving uranium monoxide-oxide the behavior of iron, molybdenum, silicon additives is adequate to that of uranium. The equation of the reducing sphere describes the uranium leaching process from its nitric acid concentrate
The Value System of Today’s Students: From Family Well-Being to Self-Realisation
The article was submitted on 24.10.2022.Социальные изменения новейшего времени оказывают влияние на ценностные предпочтения молодых людей. В статье представлены результаты комплексного лингвокогнитивного и социопсихологического экспериментального исследования, проведенного коллективом лингвистов Уральского федерального университета, целью которого является определение ценностных координат студенческой молодежи. На первом этапе на основе оригинальной процедуры выявления ключевых концептов русского менталитета был сконструирован список из 59 общенациональных базовых ценностей, который был предъявлен 633 студентам-первокурсникам Уральского федерального университета. В результате содержательной интерпретации материала установлено, что поколение молодых людей, родившихся в постсоветской России, становится носителем новых ценностей. Отсутствие интереса к политическим институтам, формирование Я-менталитета и микросолидарности в рамках узкого круга семьи и близких людей – эти ценностные предпочтения очертили ядро из восьми базовых концептов, имеющих абстрактный характер, которое потребовало своей конкретизации. На следующем этапе исследования анкета, включающая развернутую смысловую структуру ядерных концептов, была предъявлена студентам-первокурсникам (650 респондентов) с целью определения ядерных и периферийных концептуальных смыслов в языковом сознании студенческой молодежи. Кластерный анализ материала показал, что верхнюю ступень дендрограммы занимает концепт благополучие близких людей. В работе показана динамика в осмыслении аксиологемы благополучие. По данным исторических и церковнославянских лексикографических источников, языковая единица благополучие уже с XI в. имплицитно совмещает в себе ценности материального, физического и идеального, духовного, что подтверждают словари ХХ в. Студенты эксплицируют свой выбор в пользу духовной стороны благополучия. Показано, что на верхних ступенях дендрограммы в комплексе представлены четыре базовых ценности: концепты семья, самореализация, вера и счастье. Подтвердился статус ценностного смысла самореализация для молодых людей студенческого уровня, который напрямую связан с семьей и ее благополучием. Из набора когнитивных признаков концепта вера студенты предпочли ценностный смысл уверенность в своих силах, что позволяет сделать вывод, что они склонны чувствовать веру в собственные способности и возможности, обладают позитивной самооценкой, испытывают доверие к себе. Ценности, включающие материальное благополучие, находятся на периферии языкового сознания молодежи, что не укладывается в общепринятую картину наблюдаемого прагматического отношения молодежи к современной действительности. Высказано предположение, что сложившаяся картина иерархии ценностных признаков носит декларативный характер: молодые люди, недавно окончившие школу, имеют твердые представления о необходимых нормах социального поведения, сложившихся в российском обществе, поэтому ставят духовные ценности выше материальных.The social changes of the modern era influence young people’s value preferences. This paper presents the results of a comprehensive linguo-cognitive and sociopsychological experimental study by a team of linguists from Ural Federal University, which aims to determine students’ value coordinates. In the first stage, based on the original procedure for revealing the key concepts of Russian mentality, the authors constructed a list of 59 nationwide core values and presented them to 633 first-year students at Ural Federal University. As a result of further content interpretation of the material, the researchers discovered that the generation of young people born in post-Soviet Russia is becoming a bearer of new values. The lack of interest in political institutions, the formation of self-mentalism, and micro-solidarity within the narrow circle of family and close people – these value preferences outlined a core of eight basic concepts, having an abstract nature, which required concretisation. At the next stage, the authors presented a questionnaire including a detailed semantic structure of nuclear concepts to first-year students (650 respondents) to determine the nuclear and peripheral conceptual meanings in students’ language consciousness. The cluster analysis of the material demonstrated that the top level of the dendrogram is occupied by the concept of the well-being of loved ones. The paper reveals the complex semantics of the “well-being” concept and shows the axiological dynamics in comprehending the axiologeme. According to historical and Church Slavonic lexicographic sources, the “well-being” linguistic unit has implicitly combined the values of the material, physical, ideal, and spiritual since the eleventh century. Twentieth-century dictionaries confirm the presence of two zones in the semantics of the concept, i. e. the inseparable unity of the spiritual and the material. Students express their choice in favour of the spiritual side of well-being. The article shows that on the upper levels of the dendrogram, there are four basic values in a complex: the concepts of family, self-realisation, faith, and happiness. Also, the authors confirm the status of the self-realisation value sense for young people at the student level, which is directly related to the family and its well-being. As for the cognitive attributes of the faith concept, the students preferred the selfrealisation value sense, which suggests that the respondents have faith in their abilities and capabilities, positive self-esteem, and trust in themselves. Values related to material well-being are on the periphery of the linguistic consciousness of Ural youth, which does not fit in the general picture of the observed pragmatic attitude of young people to modern reality. It has been suggested that the current picture of the hierarchy of value attributes is declarative: young people who have recently left school have a clear idea of the necessary norms of social behaviour established in Russian society, and they put spiritual values over material ones
Molecular genetic diversity of flax cultivars (<i>Linum usitatissimum</i> L.) represented in the State Register for Selection Achievements of the Russian Federation
Background. When researching crop genetic diversity, including flax species, molecular markers are used to identify cultivars, establish phylogenetic relationships among them and select valuable genotypes and sources of useful traits. One of the effective ways to solve these tasks is the use of SSR markers, as a molecular method. The aim of this work was to study the molecular genetic polymorphism of modern flax cultivars listed in the State Register for Selection Achievements of the Russian Federation, find out their phylogenetic relationships and develop a version of their genetic certification.Materials and methods. The materials for the research were 82 flax cultivars (60 cultivars of fiber flax and 22 of oilseed flax) and 3 ancient landraces. Genetic analysis was carried out using the PCR method with a set of 11 SSR markers labeled with fluorescent dyes, followed by the detection of products on the genetic analyzer.Results. The study of the cultivars revealed 50 alleles at 11 loci, with the number of alleles per locus ranging from 2 to 10, averaged to 4.55 alleles per locus. Each flax sample contained a unique set of alleles.Conclusion. The resulting SSR database made it possible to develop genetic certificates for each cultivar in the form of an alphanumeric code. A cluster analysis was also carried out and a dendrogram of genetic similarity was constructed. The identified sib relationships among the cultivars confirmed the information about their origin
Relation Between the Thickness of Stellar Disks and the Relative Mass of Dark Halo in Galaxies
We consider a thickness of stellar disks of late-type galaxies by analyzing
the R and K_s band photometric profiles for two independent samples of edge-on
galaxies. The main goal is to verify a hypotesis that a thickness of old
stellar disks is related to the relative masses of the spherical and disk
components of galaxies. We confirm that the radial-to-vertical scale length
ratio for galactic disks increases (the disks become thinner) with the
increasing of total mass-to-light ratio of the galaxies, which characterize the
contribution of dark halo to the total mass, and with the decreasing of central
deprojected disk brightness (surface density). Our results are in good
agreement with numerical models of collisionless disks evolved from subcritical
velocity dispersion state to a marginally stable equilibrium state. This
suggests that in most galaxies the vertical stellar velocity dispersion, which
determine the equilibrium disk thickness, is close to the minimum value, that
ensures disk stability. The thinnest edge-on disks appear to be low brightness
galaxies (after deprojection) in which a dark halo mass far exceeds a mass of
the stellar disk.Comment: 13 pages. To be Published in Astronomy Letters, v.28(2002
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