Supersymmetry in Quantum Mechanics of Colored Particles

The role of supercharge operators is studied in the case of a Dirac particle moving in a constant chromomagnetic field. The Hamiltonian is factorised and the ground state wave function in the case of unbroken supersymmetry is determined.Comment: 8 pages, no figure

The strong thirteen spheres problem

The thirteen spheres problem is asking if 13 equal size nonoverlapping spheres in three dimensions can touch another sphere of the same size. This problem was the subject of the famous discussion between Isaac Newton and David Gregory in 1694. The problem was solved by Schutte and van der Waerden only in 1953. A natural extension of this problem is the strong thirteen spheres problem (or the Tammes problem for 13 points) which asks to find an arrangement and the maximum radius of 13 equal size nonoverlapping spheres touching the unit sphere. In the paper we give a solution of this long-standing open problem in geometry. Our computer-assisted proof is based on a enumeration of the so-called irreducible graphs.Comment: Modified lemma 2, 16 pages, 12 figures. Uploaded program packag

Unintentional high density p-type modulation doping of a GaAs/AlAs core-multi-shell nanowire

Achieving significant doping in GaAs/AlAs core/shell nanowires (NWs) is of considerable technological importance but remains a challenge due to the amphoteric behavior of the dopant atoms. Here we show that placing a narrow GaAs quantum well in the AlAs shell effectively getters residual carbon acceptors leading to an \emph{unintentional} p-type doping. Magneto-optical studies of such a GaAs/AlAs core multi-shell NW reveal quantum confined emission. Theoretical calculations of NW electronic structure confirm quantum confinement of carriers at the core/shell interface due to the presence of ionized carbon acceptors in the 1~nm GaAs layer in the shell. Micro-photoluminescence in high magnetic field shows a clear signature of avoided crossings of the $n=0$ Landau level emission line with the $n=2$ Landau level TO phonon replica. The coupling is caused by the resonant hole-phonon interaction, which points to a large 2D hole density in the structure.Comment: just published in Nano Letters (http://pubs.acs.org/doi/full/10.1021/nl500818k

AUTODIDACTIC FOR PARENTS OF CHILDREN STUDYING IN MULTI-ETHNIC SCHOOL ENVIRONMENT

Purpose: The article is aimed at describing a model of self-education of primary school children's parents and the results of its testing in a primary school in a multi-ethnic educational space. The leading technology of organizing self-education for parents of primary students and formation of their methods of auto-didactics is the technology of poly directional pedagogical counseling. Methodology: The following methods of measuring the effectiveness of the offered program were used: SWOT - analysis of educational problems of primary school children in a multi-ethnic educational organization, analysis of research data on related topics, pedagogical modeling, studying students' work, observation, and survey methods with graphical interpretation of the data. Result: The result of the study was a unique model of inclusion of primary students’ parents in the educational space of a multi-ethnic school. In accordance with the authors' model, an awareness program was launched for parents of primary school children. Applications: The research materials can be useful for primary school teachers, for parents of primary students, as well as for specialists in the system of additional education in working with multi-ethnic children groups, as well as for social teachers in working with migrant families to build a non-conflict educational environment. Novelty/Originality: The originality of the study lies in the development of a model for the inclusion of parents of younger schoolchildren in the educational space of a multi-ethnic school through parental self-education organized by school teachers

Tecnología para la formación temprana de resistencia al estrés en el sistema de prevención de la mala adaptación escolar de alumnos de primer grado

The relevance of the stated problem of the crisis of 6-7-year old’s is dictated by the recently growing tendency to bring back children to preschool institutions after a short period at school by parents who notice the child’s painful condition associated with school maladaptation. In this regard, many researchers and practicing educators recommend reviewing the start dates for children at school so that the child starts school at the age of seven. Other teachers notice a significant increase in the work load on primary schoolchildren connected to the introduction of the Federal State Educational Standard for Primary General Education and the corresponding forms of control and assessment activities. Thus, there was a need to develop new technologies to preserve the health of younger students and allow them to overcome the crisis of the onset of education. The purpose of this article is to describe the developed technology aimed at helping 6-7-year old to overcome the age crisis and prevent school maladaptation with the help of early formation of stress tolerance. The main method in the study is the design of a technology for early formation of stress tolerance and prediction of the results of its implementation in the experimental groups of 6-7-year-old children. The technology is based on the principles of continuity of the educational process between preschool educational organizations and schools. With the implementation of the developed technology the following results were achieved: increased motivation for success and higher somatic health level manifested in sport and creative activities. The above-mentioned results in their turn contributed to crisis prevention, school deprivation of first graders and comfortable overcoming of the crisis of 6-7 year olds. The materials of the article can be useful to organizers of sport and creative activities in preschool educational institutions, educators of preparatory groups, teachers, methodologists in preschool and primary education, as well as physical education teachers and primary school teachers. The materials of the article can be used in the system of advanced training of teachers of physical education and elementary school, as well as in the preparation for professional activities in preschool educational institutions and elementary schools of students of teacher training colleges and universities.La relevancia del problema declarado de la crisis de los niños de 6 a 7 años está dictada por la tendencia cada vez mayor de traer a los niños a las instituciones preescolares después de un corto período en la escuela por parte de los padres que notan la condición dolorosa del niño asociada con la mala adaptación escolar. En este sentido, muchos investigadores y educadores en ejercicio recomiendan revisar las fechas de inicio de los niños en la escuela para que el niño comience la escuela a la edad de siete años. Otros maestros notan un aumento significativo en la carga de trabajo de los escolares de primaria relacionados con la introducción del Estándar Educativo del Estado Federal para la Educación General Primaria y las formas correspondientes de actividades de control y evaluación. Por lo tanto, era necesario desarrollar nuevas tecnologías para preservar la salud de los estudiantes más jóvenes y permitirles superar la crisis del inicio de la educación. El propósito del artículo es describir la tecnología desarrollada destinada a ayudar a niños de 6 a 7 años a superar la crisis de la edad y prevenir la mala adaptación escolar con la ayuda de la formación temprana de tolerancia al estrés. El método principal en el estudio es el diseño de una tecnología para la formación temprana de tolerancia al estrés y la predicción de los resultados de su implementación en los grupos experimentales de niños de 6-7 años. La tecnología se basa en los principios de continuidad del proceso educativo entre las organizaciones educativas preescolares y las escuelas. Con la implementación de la tecnología desarrollada se lograron los siguientes resultados: mayor motivación para el éxito y un mayor nivel de salud somática manifestado en actividades deportivas y creativas. Los resultados mencionados a su vez contribuyeron a la prevención de crisis, la privación escolar de los alumnos de primer grado y la superación cómoda de la crisis de los niños de 6 a 7 años. Los materiales del artículo pueden ser útiles para los organizadores de actividades deportivas y creativas en instituciones educativas preescolares, educadores de grupos preparatorios, maestros, metodólogos en educación preescolar y primaria, así como maestros de educación física y maestros de primaria. Los materiales del artículo se pueden utilizar en el sistema de formación avanzada de docentes de educación física y primaria, así como en la preparación de actividades profesionales en instituciones educativas preescolares y escuelas primarias de estudiantes de escuelas de formación de docentes y universidades

Synthesis of novel 6-substituted sulfur-containing derivatives of pyridoxine

An efficient synthesis of novel 6-substituted derivatives of pyridoxine was achieved. The reactions of various thiols with mono-, bis-, and tris(hlorine) derivatives of 6-methyl-2,3,4-tris(hydroxymethyl)pyridin-5-ol (6-hydroxymethylpyridoxine) gave sulfur-containing derivatives of pyridoxine. © 2012 Elsevier Ltd. All rights reserved

Homogeneous Liquid Phase Transfer of Graphene Oxide into Epoxy Resins

© 2017 American Chemical Society.The quality of polymer composite materials depends on the distribution of the filler in the polymer matrix. Due to the presence of the oxygen functional groups, graphene oxide (GO) has a strong affinity to epoxy resins, providing potential opportunity for the uniform distribution of GO sheets in the matrix. Another advantage of GO over its nonoxidized counterpart is its ability to exfoliate to single-atomic-layer sheets in water and in some organic solvents. However, these advantages of GO have not yet been fully realized due to the lack of the methods efficiently introducing GO into the epoxy resin. Here we develop a novel homogeneous liquid phase transfer method that affords uniform distribution, and fully exfoliated condition of GO in the polymer matrix. The most pronounced alteration of properties of the cured composites is registered at the 0.10%-0.15% GO content. Addition of as little as 0.10% GO leads to the increase of the Young's modulus by 48%. Moreover, we demonstrate successful introduction of GO into the epoxy matrix containing an active diluent-modifier; this opens new venues for fabrication of improved GO-epoxy-modifier composites with a broad range of predesigned properties. The experiments done on reproducing the two literature methods, using alternative GO introduction techniques, lead to either decrease or insignificant increase of the Young's modulus of the resulting GO-epoxy composites

Features of Reaction of 2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphorin-4-one with 1,2-Dicarbonyl Compounds

© 2018, Pleiades Publishing, Ltd. 2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphorin-4-one reacts with perfluorodiacetyl, 3,6-di(tert-butyl)-1,2-benzoquinone and phenanthrenequinone only with the participation of a three-coordinated phosphorus atom to form spirophosphoranes containing acyclic 5-methyl-2- phenyl-2H-1,2,3-diazaphosphol-4-yl substituent, whereas the interaction with tetrachloro-1,2-benzoquinone proceeds via expanding the six-membered heterocycle to the nine-membered one to form 2-(2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-2,9-dioxo-4,5,6,7-tetrachlorodibenzo[d,h]-1,3,8-trioxaphosphonine

ОПТИМІЗАЦІЯ РОБОТИ ЧЕРГОВОГО МЕТЕОРОЛОГА ІЗ ВИКОРИСТАННЯМ АВТОМАТИЗОВАНОГО РОБОЧОГО МІСЦЯ СИНОПТИКА

У статті на підставі відпрацьованого великого обсягу метеоінформації, яка надходить до метеослужби у різні періоди часу, проведено аналіз досвіду метеорологічного забезпечення польотів авіації різних рівнів, запропоновано опрацювання прогностичних даних та розроблені рекомендації для чергового метеоролога щодо метеорологічного забезпечення польотів авіації з використанням автоматизованого робочого місця синоптика

Reaction of 2-methoxy-1,3,2-dioxa-phosphorino[4,5-b]pyridin-4(4H)-one with hexafluoroacetone

The reaction of the di-O-trimethylsilyl derivative of 2-hydroxynicotinic acid with methyl phosphodichloridite afforded 2-methoxy-1,3,2- dioxaphosphorino[4,5-b]pyridin-4(4H )-one. The NMR spectrkscopic data suggest that the reaction of the latter with hexafluoroacetone produces unstable 2-methoxy-2,5-dioxo-4,4-bis(trifluoromethyl)-4,5-dihydro-1,3,2-dioxa- phosphepino[4,5-b]pyridine, which is readily transformed into 9-methyl-2,5-dioxo-4,4- bis(trifluoromethyl)-4,5-dihydro-1,3,2- dioxaphosphepino[4,5-b]pyrid-9-inium-2-oate. The structure of the hydrolysis product of the latter, viz., 1-methyl-3-(2-hydroxy-3,3,3-trifluoro-2- trifluoromethylpropanoyl)pyridin-2-one, was established by X-ray diffraction analysis. © 2004 Springer Science+Business Media, Inc