Dimension on Discrete Spaces

In this paper we develop some combinatorial models for continuous spaces. In this spirit we study the approximations of continuous spaces by graphs, molecular spaces and coordinate matrices. We define the dimension on a discrete space by means of axioms, and the axioms are based on an obvious geometrical background. This work presents some discrete models of n-dimensional Euclidean spaces, n-dimensional spheres, a torus and a projective plane. It explains how to construct new discrete spaces and describes in this connection several three-dimensional closed surfaces with some topological singularities It also analyzes the topology of (3+1)-spacetime. We are also discussing the question by R. Sorkin [19] about how to derive the system of simplicial complexes from a system of open covering of a topological space S.Comment: 16 pages, 8 figures, Latex. Figures are not included, available from the author upon request. Preprint SU-GP-93/1-1. To appear in "International Journal of Theoretical Physics

Cosmological scalar fields that mimic the ΛCDM\Lambda CDM cosmological model

We look for cosmologies with a scalar field (dark energy without cosmological constant), which mimic the standard $\Lambda CDM$ cosmological model yielding exactly the same large-scale geometry described by the evolution of the Hubble parameter (i.e. photometric distance and angular diameter distance as functions on $z$). Asymptotic behavior of the field solutions is studied in the case of spatially flat Universe with pressureless matter and separable scalar field Lagrangians (power-law kinetic term + power-law potential). Exact analytic solutions are found in some special cases. A number of models have the field solutions with infinite behavior in the past or even singular behavior at finite redshifts. We point out that introduction of the cosmological scalar field involves some degeneracy leading to lower precision in determination of $\Omega_m$. To remove this degeneracy additional information is needed beyond the data on large-scale geometry.Comment: VIII International Conference "Relativistic Astrophysics, Gravitation and Cosmology": May 21-23, 2008, Kyiv, Ukrain

Movement Coordination: Peculiarities of Strength Effort Assessment in Girls Aged 11-13

The purpose of the study is to determine the peculiarities of strength effort assessment in girls aged 11-13. Materials and methods. The study participants were girls aged 11 (n=25), 12 (n=27), 13 (n=18). The children and their parents were fully informed about all the features of the study and agreed to participate in the experiment. The paper used methods of scientific literature analysis, testing, methods of mathematical statistics. To determine the peculiarities of strength effort assessment, the study used a t-test for paired observations and a t-test for independent samples. Results. The girls aged 11-13 demonstrate the best assessment of effort reproduction at 2/3 of maximum strength. There is no statistically significant age-related dynamics in strength effort assessment in girls aged 11-13. The correlation between the effort reproductions at 1/3, 1/2 and 2/3 of maximum strength is not statistically significant. Conclusions. In the process of physical education of girls aged 11-13, special attention should be paid to the development of motor control ability as the component of coordination training of schoolchildren

Phase Diagram of the AgGaS2–AgIn5S8 System

На основі результатів рентгенофазового (РФА) та диференційно-термічного (ДТА) аналізів побудовано діаграму стану системи AgGaS2–AgIn5S8. According to the results of X-ray and differential-thermal analysis, phase diagram of the system AgGaS 2–AgIn5S8 was constructed

AgInSe2 – AgGaSe2 and AgInSe2 – Ag9GaSe6 systems

Враховуючи дані, отримані за результатами РФА, МСА, ДТА та поміру мікротвердості, було побудовано діаграми стану систем AgInSe2 – AgGaSe2 та AgInSe2 – Ag9GaSe6. У системі AgInSe2 – AgGaSe2 існує евтектична точка LE ↔ α + β при 1030 К та 24 мол. % AgGaSe2, де α – тверді розчини на основі високотемпературної модифікації (ВТМ) AgInSe2, β – тверді розчини на основі сполуки AgGaSe2 та низькотемпературної модифікації (НТМ) AgInSe2. Нескінченний ряд β-твердих розчинів кристалізується в структурі халькопіриту. В системі AgInSe2 – Ag9GaSe6 існує евтектична точка LE ↔α + γ при 960 К та 60 мол. % AgGaSe2. According to the data obtained from the results of X-ray, X-ray structural, microstructural, differential-thermal analysis and measurement of microhardness, phase diagrams of the systems AgInSe 2 – AgGaSe2 and AgInSe2 – Ag9GaSe6 were constructed. There is eutectic point LE ↔ α + β at 1030 К and 24 mol. % AgGaSe2 in the AgInSe2 – AgGaSe2 system, where α – solid solutions based on the high-temperature modification (HTM) of AgInSe 2, β – solid solutions based on the compound AgGaSe2 and low-temperature modification (LTM) of AgInSe 2. A continuous series of β-solid solutions crystallize in the chalcopyrite structure. There is eutectic point L E ↔ α + γ at 960 К and 60 mol. % AgGaSe2 in the AgInSe2 – Ag9GaSe6 system

Хімія твердого тіла

В навчальному посібнику через розгляд таких питань, як механізм виникнення електропровідності в твердих тілах, зонна структура, статистика електронів в твердих тілах та хімічний потенціал, будова реальних кристалів, поверхневі властивості напівпровідників, основні поняття про реакції в твердих тілах, подаються теоретичні основи будови твердого тіла. Розглядаються питання властивостей напівпровідників: елементарних, бінарних, тернарних та тетрарних, склоподібних, органічних, феритів, сегнетоелектриків та люмінофорів. Навчальний посібник «Хімія твердого тіла» підготовлений для студентів хімічного факультету, спеціальності 8.04010101 «Хімія», який необхідний для вивчення курсу «Хімія твердого тіла» та для студентів спеціальності 7.04010101 «Хімія», що вивчають курс «Хімія напівпровідників». Він буде дуже корисним при виконанні дипломних та магістерських робіт, а також при роботі над кандидатськими дисертаціями не тільки студентам-хімікам, але і студентам фізичного факультету та усім, хто цікавиться сучасними проблемами хімії твердого тіла та напівпровідників.Даний посібник є першою спробою систематизувати та узагальнити накопичений авторами викладацький та науковий досвід в області хімії твердого тіла та хімії напівпровідників, тому будемо раді отримати конструктивні зауваження і побажання на адресу: [email protected]. Всі розділи посібника написані у співпраці укладачів проф., д.х.н., завідувача кафедри неорганічної та фізичної хімії Східноєвропейського національного університету ім. Лесі Українки І.Д. Олексеюка, доц., к.х.н. О.В. Парасюка та доц., к.х.н. І.А. Іващенко

Motor Abilities: Peculiarities of Strength Effort Assessment in Boys Aged 11-13

Thepurposeofthestudyistodetermine the peculiarities of strength effort assessmentin boys aged 11-13. Materials and methods.The study participants were boys aged 11 years (n=22), 12 years (n=31), 13 years (n=33). The children and their parents were fully informed about all the features of the study and gave their consent to participate in the experiment. The paper used methods of scientific literature analysis, testing, methods of mathematical statistics. The study assessedthe right hand effort at 1/3, 1/2, 2/3 of the maximum. The assessment error was analyzed. To determine the peculiarities of strength effort assessment, the study used a t-test for paired observations and a t-test for independent samples. Results. The analysis of the ability for strength effort assessment in the boys aged 11 and 13 showed that there are no statistically significant differences between the boys of this age. The boysdemonstrate the best assessment ofeffortat2/3 of the maximum. There areno statistically significant differences in the levels of development of the hand maximum strength (p > 0.05). Thestudy has not found statistically significant differences in the levels of development of the ability for strength effort assessment in the boys aged 11-13(p > 0.05). The boys of this age demonstrate the best assessment ofeffortat2/3 of the maximum. A comparative analysis of the ability for strength effort assessment in the boys aged 12 and 13 did not reveal statistically significant differences (p > 0.05). The boys of this age demonstrate the best assessment ofeffortat2/3 of the maximum. The boys aged 11–13 show the best assessment of effort reproduction at2/3 of the maximum (p < 0.05). There is no statistically significant age-related dynamics in strength effortassessment in the boys aged 11-13. The correlationbetween the effort reproductionsat1/3, 1/2 and 2/3 of the maximum is not statistically significant. Conclusions.In the process of physical education of boys aged 11–13,special attention should be paid to the development of motor control ability as the component of coordination training of schoolchildren

Gravitational Ionization: A Chaotic Net in the Kepler System

The long term nonlinear dynamics of a Keplerian binary system under the combined influences of gravitational radiation damping and external tidal perturbations is analyzed. Gravitational radiation reaction leads the binary system towards eventual collapse, while the external periodic perturbations could lead to the ionization of the system via Arnold diffusion. When these two opposing tendencies nearly balance each other, interesting chaotic behavior occurs that is briefly studied in this paper. It is possible to show that periodic orbits can exist in this system for sufficiently small damping. Moreover, we employ the method of averaging to investigate the phenomenon of capture into resonance.Comment: REVTEX Style, Submitte

Basal Respiration as a Proxy to Understand Spatial Trends in CO2 Emissions in the Moscow Region

Soil respiration (Rs) is an important terrestrial CO2 efflux and receives significant attention at different scale levels. However, the sampling density is limited and global Rs databases are biased towards natural ecosystems. Urbanization is among the most important current land-use trends and its role will likely grow in the future. Urban soils store considerable amount of carbon and are very heterogeneous and dynamic, which affects Rs. Our understanding of the Rs spatial variability is limited, especially for the regions with heterogeneous bioclimatic conditions and high urbanization level. The methodological constraints of direct Rs measurements in the field limit the number of observations. As an alternative approach to approximate the spatial variability of Rs, we used basal respiration (BR) as an indirect measurement. We implemented digital soil mapping technique to map BR as a proxy of Rs in a heterogeneous and urbanized Moscow Region. Topsoil and subsoils BR maps were developed for the region and spatial variability per land-use and soil type was analyzed. BR averaged for the urban areas was lower than in forests and meadows, however, urban areas became the hotspots of BR’s spatial variability in the region. Considerable contribution of subsoil layers to the total BR was also found with the maximal 30% contribution in urban soils. Although the absolute levels of respiration remained uncertain, the spatial patterns of BR are likely to correspond well with Rs patterns, determined by soil type, land use and allocation of urban areas