264 research outputs found
Weak Interaction Contributions in Light Muonic Atoms
Weak interaction contributions to hyperfine splitting and Lamb shift in light
electronic and muonic atoms are calculated. We notice that correction to
hyperfine splitting turns into zero for deuterium. Weak correction to the Lamb
shift in hydrogen is additionally suppressed in comparison with other cases by
a small factor .Comment: Minor editorial corrections, reference added, version to be published
in Phys. Rev.
Changes in the species composition and abundance of young-of-the-year fishes in the upper Volga stretch of the Kuibyshev Reservoir during the period of 1991 to 2009
© 2014, Pleiades Publishing, Ltd. The species composition and abundance of young-of-the-year fishes have been analyzed in catches made in the upper Volga stretch of the Kuibyshev Reservoir between 1991 and 2009. It has been found that the juvenile abundance of roach and blue bream has decreased, while that of perch, silver bream, and spined loach has increased, with young-of-the-year juveniles of common rudd, tubenose goby, round goby, and black-striped pipefish appearing in catches. The results of the study show that, against the background of juvenile population decline in many spring-spawning fish species, the abundance and species diversity of young of the year in summer-spawning species has increased during the observation period
Nonlinear monotonization of the Babenko scheme for the quasi‐linear advection equation
The paper is devoted to construction and development of new method for numerical solution of hyperbolic type equations [14, 17].
In the previous papers [4, 5, 6, 7, 8, 9] authors have investigated theoretically and tested experimentally 26 different finite‐difference schemes on 4 point patterns for the simplest hyperbolic equation: linear advection equation. This equation has the main features of every hyperbolic equation and is the important part of many mathematical models. In other cases the advection operator is the important part of the full operator of the problem. All 26 schemes have been compared experimentally on the special representative set of tests. Nevertheless to simplicity of the equation, almost all schemes have different disadvantages. They are discussed in detail in the cited papers. So, the investigation of new schemes for this equation is still an important task.
In [4, 5, 6, 7, 8, 9] some new schemes were constructed for solving this advection equation. The nonlinear monotone Babenko scheme ("square") proved to be the best among all 26 schemes. So, it is a big interest to generalize this scheme to more difficult equations. The important example is a quasi‐linear advection equation.
In this paper our basic aim is to construct a quasi‐monotone nonlinear Babenko scheme for solving the quasi‐linear advection equation and to test it experimentally. The monotonisation of the scheme is done by adding the artificial diffusion with limiters. We also present advanced results of comparative analysis of the new scheme with other known schemes. We have considered explicit and implicit upwind approximation schemes [4, 6, 13, 16] which is firstorder accurate in time and space, the Lax‐Wendroff scheme [4] which is the first order accurate in time and second order accurate in space. We also analyze the monotonised “Cabaret” scheme proposed in [10, 11]. It is second order accurate in time and space, and its monotonisation is based on apriori knowledge of the dependence region of the exact solution. The authors of this scheme called it by “jumping advection”. The considered schemes are compared numerically by using a set of tests, which is similar to one used in [4, 5, 6, 8].
Šiame straipsnyje pasiūlyta kvazi‐monotonie netiesine Babenkos skirtumu schema kvazitiesinei pernešimo lygčiai spresti. Schemos monotoniškumas pasiekiamas pridedant dirbtine difuzija su apribojimais. Pateiktas šios schemos palyginimas su kitomis schemomis. Taip pat analizuojama antros eiles pagal laika ir erdve monotonine “Cabaret” schema. Pateikti testu rezultatai.
First Published Online: 14 Oct 201
Inclusion of the Förster-rate orientation factor into the theory of concentration self-quenching by statistical traps
The incorporation is studied of the orientation factor occurring in the complete Förster rate of incoherent energy transfer, into the theory of concentration self-quenching by statistical pairs of luminescent molecules. Within Burshtein’s theory of hopping transport, exact results for the steady state donor fluorescence yield and emission anisotropy are obtained for three-dimensional systems. Two opposite limits to treat the orientations of the molecular transition dipoles within statistical pairs are considered, and it appears that in both cases the fluorescence yield is substantially influenced by inclusion of the orientation factor into the transfer kinetics
Structure and evolution of dune massifs in the Vilyui River Basin over the Late Quaternary Period (by the example of the Makhatta and Kysyl-Syr Tukulans)
© 2017, Pleiades Publishing, Ltd. The data of the comprehensive study of deposits of dune sand massifs—the Makhatta and Kysyl-Syr Tukulans—in the Vilyui River Basin (Central Yakutia) are given. We have revealed the structure and preliminarily reconstructed the evolution of tukulans in the Vilyui River basin and the environmental conditions of the surrounding area in the Late Pleistocene–Holocene period (the chronological period of the formation of tukulans) on the basis of lithological and palynological data and 17 radiocarbon datings. It has been revealed that the tukulans should be assigned to eolian deposits formed on sediments of complicated facial structure. We have distinguished four stages in the vegetation evolution within the last 40000-year period and three chronostratigraphical phases in the development of dune massifs
The size and age composition of roach Rutilus rutilus (L.) at the upper part of the Kuibyshev reservoir Volga reach
© 2016,International Journal of Pharmacy and Technology. All rights reserved.The size-and-age structure as well as indexes of the linear roach growth of the Volga upper reach of the Kuibyshev reservoir during 2010-2014 are considered. Material was gathered during control fishery with stationary nets. It is established that in the catch female small fries prevailed. Low level of average length indexes and the relative simplified nature of age structure around research reflect instability of population reproduction and high level of fishing pressure. The reconstructed indicators of the linear growth of roach on materials 2013 and 2014 years were substantially lower,both on different sites of the Kuibyshev reservoir,and on materials concerning the Volga River before the reservoir foundation. It is the result of the deterioration tendency continuation in roach growth in the Volga reach revealed earlier
Near infrared light emission quenching in organolanthanide complexes
We investigate the quenching of the near infrared light emission in Er3+ complexes induced by the resonant dipolar interaction between the rare-earth ion and high frequency vibrations of the organic ligand. The nonradiative decay rate of the lanthanide ion is discussed in terms of a continuous medium approximation, which depends only on a few, easily accessible spectroscopic and structural data. The model accounts well for the available experimental results in Er3+ complexes, and predicts an similar to 100% light emission quantum yield in fully halogenated systems
Каменные глетчеры хребта Сунтар‑Хаята
The remote map‑making technique and results of field investigations made possible for the first time to reveal a great number of rock glaciers within the area of the Suntar‑Khayata Range (North‑East Asia). A total of 540 formations were identified. Among them, 47 rock glaciers were classified as corrie (cirque) tongue‑shaped formations and 493 ones – as niche lobe‑shaped (single‑ and multi‑lobe) rock glaciers. Occurrence of such formations is 8.4/100 km2, that is the largest in the North‑East Asia. The rock glaciers in this region are found within a range of true altitudes from 1297 up to 2402 m asl. The majority of active features, however, are confined to the interval between 1500 and 1900 m asl. Rock glaciers occur in the altitudinal range of 1297 to 2402 m asl. The majority of active features, however, are confined to the interval between 1500 and 1900 m asl, and the main part of active formations is located within the range of 1500‑2500 m. The frequency analysis of true altitudes of the rock‑glacier occurrence indicates that their formation can be caused by the hypsometry of the region relation to morphoclimatic zonality.Методы дистанционного картографирования и результаты экспедиционных обследований позволили впервые установить значительное число каменных глетчеров в пределах хребта Сунтар‑Хаята. Всего идентифицировано 540 каменных глетчеров. Установленные каменные глетчеры различных типов распространены в интервале высот 1300–2400 м над ур. моря и представляют собой индикаторную формацию горной криолитозоны и перигляциального пояса
Biographical reflection and readiness to master age-related changes at a senior age
The article presents the results of an empirical study of psychological readiness to master age.related changes and biographical reflection in the elderly in the context of professional employment. A comparison of the level of biographical reflection and readiness for age.related changes in working and non.working pensioners was carried out, and the nature of the relationship between these phenomena was described.This study was funded by the Russian Foundation for Basic Research Grant № 19‑013‑00431
Description of <i>Saccharina japonic</i>a commercial stock in the Aniva Bay (Okhotsk Sea) //
Stock of Saccharina japonica in the Aniva Bay (Okhotsk Sea coast of Sakhalin Island) was surveyed by divers in 2010 and assessed with the squares method. The total stock decreased slightly as compared with the previous year (from 47,800 to 43,560 t) but the commercial stock became higher (42,410 t in 2010 against 40,900 t in 2009). The area of traditional harvesting (7.52 km2) was > 80 % covered by the two-years-old algae with total biomass 35,120 t, their highest density (8.9 ind./m², 4.7 kg/m²) was observed in the internal part of the bay. However, the algae in this area had the minimal size parameters (length, thickness, weight), whereas the largest thalli with length 309.7 cm, width 24.2 cm, thickness in the middle strip 3.1 mm, and weight 978.6 g were registered in the external part of the bay. Besides, the algae of the internal part accumulated in their tissues more metals and toxic elements, as calcium, copper, potassium, iron, manganese, zinc, arsenic, lead, and cadmium. The arsenic content in the samples from the internal part varied in the range 0.94-26.60 mg/kg, the highest value was in 5.3 times higher than the maximum permissible level, following to Sanitary Rules and Norms 3.2.1078-01. The content of lead and cadmium did not exceed the established norms, even in the top of the Bay
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