354 research outputs found

    Dynamics and configurations of galaxy triplets

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    The purpose is to infer the probable dynamical states of galaxy triplets by the observed data on their configurations. Two methods are proposed for describing the distributions of the triplet configuration parameters characterizing a tendency to alignment and hierarchy: (1) obtaining a representative sample of configurations and determining its statistical parameters (moments and percentages); and (2) dividing the region of possible configurations of triple systems (Agekian and Anosova, 1967) into a set of segments and finding the probabilities for the configurations to find themselves in each of them. Both these methods allow representation of the data by numerical simulations as well as observations. The effect of projection was studied. It rather overestimates the alignment and hierarchy of the triple systems. Among the parameters of interest there are found some parameters that are least sensitive to projection effects. The samples consist of simulated galaxy triplets (with hidden mass) as well as of 46 probably physical triple galaxies (Karachentseva et al., 1979). The observed triples as well as numerical models show a tendency to alignment. The triple galaxies do not show any tendency to hierarchy (formation of the temporary binaries), but this tendency may be present for simulated triplets without significant dark matter. The significant hidden mass (of order ten times the total mass of a triplet) decreases the probability of forming a binary and so weakens the hierarchy. Small galaxy groups consisting of 3 to 7 members are probably the most prevalent types of galaxy aggregate (Gorbatsky, 1987). Galaxy triplets are the simplest groups, but dynamically nontrivial ones

    Phoebe 2.0 – Triple and multiple systems

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    Some close binary formation theories require the presence of a third body so that the binary orbit can shrink over time. Tidal friction and Kozai cycles transfer energy from the binary to its companion, resulting in a close inner binary and a wide third body orbit. Spectroscopy and imaging studies have found 40% of binaries with periods less than 10 days, and 96% with periods less than 3 days, have a wide tertiary companion. With recent advancements in large photometric surveys, we are now beginning to detect many of these triple systems by observing tertiary eclipses or through the effect they have on the eclipse timing variations (ETVs) of the inner-binary. In the sample of 2600 Kepler EBs, we have detected the possible presence of a third body in ∼20%, including several circumbinary planets. Some multiple systems are quite dynamical and feature disappearing and reappearing eclipses, apsidal motion, and large disruptions to the inner-binary. phoebe is a freely available binary modeling code which can dynamically model all of these systems, allowing us to better test formation theories and probe the physics of eclipsing binaries

    Complex support of technological development of environmentally friendly toilet systems in passenger trains

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    Ensuring environmental-oriented turnover of fecal waste in passenger transport is necessary for the preservation of ecosystems, public health and sustainable development of transport complexes. The history of Russian railway toilet complexes begins with the launch of the first railway “Petersburg – Tsarskoe Selo” in 1837. In the USSR since 1985 The Ministry of Railways of the USSR thought about the need for experimental design work on the creation of closed systems for collecting sewage for passenger rolling stock. A set of scientific works on the creation of systems and equipment that protect the environment from chemical and  biological pollution was presented in the Railway transport program for 1990-2000.The article considers the negative impact of fecal waste on the environment and public health, as well as problems related to the maintenance of environmentally friendly toilet complexes of passenger cars. The main results of technological development of toilet complexes of transport systems have been outlined. The authors note the importance of timely comprehensive support (infrastructure, technical, organizational and economic, regulatory and methodological, personnel, and other) for the technological development of toilet complexes in the transport industry. In particular, the article reviewes some of the current problems of infrastructure, regulatory and methodological, organizational and economic support for the operation and maintenance of environmentally friendly toilet complexes. For the effective functioning of the environmentally friendly toilet complexes system of transport systems, the authors propose to use organizational and methodological tools that will allow you to systematically determine the actual level of technological development of the fecal waste disposal system of the environmentally friendly toilet complexes of passenger trains, to develop directions and measures to improve its  environmental and economic efficiency

    Formalization of hydrocarbon conversion scheme of catalytic cracking for mathematical model development

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    The issue of improving the energy and resource efficiency of advanced petroleum processing can be solved by the development of adequate mathematical model based on physical and chemical regularities of process reactions with a high predictive potential in the advanced petroleum refining. In this work, the development of formalized hydrocarbon conversion scheme of catalytic cracking was performed using thermodynamic parameters of reaction defined by the Density Functional Theory. The list of reaction was compiled according to the results of feedstock structural-group composition definition, which was done by the n-d-m-method, the Hazelvuda method, qualitative composition of feedstock defined by gas chromatography-mass spectrometry and individual composition of catalytic cracking gasoline fraction. Formalized hydrocarbon conversion scheme of catalytic cracking will become the basis for the development of the catalytic cracking kinetic model

    Secondary hyperparathyroidism based on the materials of the appeal to the surgeon, endocrinologist

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    The aim of the study - to describe the tendency of secondary hyperparathyroidism in a patient with stage 5 CKD with the determination of the most effective treatment methodЦель исследования – описать тенденцию возникновения вторичного гиперпаратиреоза у пациента с ХБП 5 стадии с определением наиболее эффективного метода лечени

    High Resolution Images of Orbital Motion in the Trapezium Cluster: First Scientific Results from the MMT Deformable Secondary Mirror Adaptive Optics System

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    We present the first scientific images obtained with a deformable secondary mirror adaptive optics system. We utilized the 6.5m MMT AO system to produce high-resolution (FWHM=0.07'') near infrared (1.6 um) images of the young (~1 Myr) Orion Trapezium theta 1 Ori cluster members. A combination of high spatial resolution and high signal to noise allowed the positions of these stars to be measured to within ~0.003'' accuracies. Including previous speckle data (Weigelt et al. 1999), we analyze a six year baseline of high-resolution observations of this cluster. Over this baseline we are sensitive to relative proper motions of only ~0.002''/yr (4.2 km/s at 450 pc). At such sensitivities we detect orbital motion in the very tight theta 1 Ori B2B3 (52 AU separation) and theta 1 Ori A1A2 (94 AU separation) systems. Such motions are consistent with those independently observed by Schertl et al. (2003) with speckle interferometry, giving us confidence that these very small (~0.002''/yr) orbital motions are real. All five members of the theta 1 Ori B system appear likely gravitationally bound. The very lowest mass member of the theta 1 Ori B system (B4) has K' ~11.66 and an estimated mass of ~0.2 Msun. There was very little motion (4+/-15 km/s) detected of B4 w.r.t B1 or B2, hence B4 is possibly part of the theta 1 Ori B group. We suspect that if this very low mass member is physically associated it most likely is in an unstable (non-hierarchical) orbital position and will soon be ejected from the group. The theta 1 Ori B system appears to be a good example of a star formation ``mini-cluster'' which may eject the lowest mass members of the cluster in the near future. This ``ejection'' process could play a major role in the formation of low mass stars and brown dwarfs.Comment: To appear in the December 10, 2003 issue of the Astrophysical Journal 21 pages, 14 figures (some in color, but print OK in B&W

    Antiproliferative activity of a new derivative from the class of N-glycoside of indolo [2,3-a] pyrrolo [3,4-c] carbazoles

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    The aim of the study was to evaluate an antiproliferative activity of a new, Russian derivative of N-glycoside substituted indolocarbazole 6-amino-12-(α-L-arabinopyranosyl)indolo [2,3-a] pyrrolo [3,4-c] carbazole-5,7-dione (LCS-1208) on models of transplantable tumors of mice and on human tumors in Balb/c nude mic
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