2,372 research outputs found

    Gravitational potential of a homogeneous circular torus: new approach

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    The integral expression for gravitational potential of a homogeneous circular torus composed of infinitely thin rings is obtained. Approximate expressions for torus potential in the outer and inner regions are found. In the outer region a torus potential is shown to be approximately equal to that of an infinitely thin ring of the same mass; it is valid up to the surface of the torus. It is shown in a first approximation, that the inner potential of the torus (inside a torus body) is a quadratic function of coordinates. The method of sewing together the inner and outer potentials is proposed. This method provided a continuous approximate solution for the potential and its derivatives, working throughout the region.Comment: 10 pages, 9 figures, 1 table; some misprints in formulae were correcte

    Tectonic asymmetry of the earth and other planets

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    The structures of Earth, Mars, Venus, and the Moon are examined and compared. Global tectonic characteristics are presented for each. A comparison of the tectonics reveals the structural asymetry of these planets and the moon. Tectonic asymmetry information for the group is used to interpret certain aspects of the earth's geological past

    Soyuz 22: New contribution to earth study from space

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    The mission of space flight Soyuz-22 was to develop new and improved methods and means for finding tthe Earth's natural resources from outer space to aid the economy. With the help of the new multispectral space camera, MKF-6, the cosmonauts were able to photograph selected areas of U.S.S.R. and the German Democratic Republic in 4 visible and 2 infrared regions of the spectrum. The MKF-6 can simultaneously photograph areas in 6 spectral regions and register both the natural electromagnetic radiation of surface objects and the solar radiation reflected by them

    Monitoring and prediction of natural disasters

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    The problems of natural disaster predicting and accomplishing a synthesis of environmental monitoring systems to collect, store, and process relevant information for their solution are analyzed. A three-level methodology is proposed for making decisions concerning the natural disaster dynamics. The methodology is based on the assessment of environmental indicators and the use of numerical models of the environment

    Electrochemical Reducing of Terbium and Holmium Ions in the Sodium and Potassium Chlorides Melt with Equimolar Composition

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    Interest to rare-earth metals (REM) and their alloys is due to the possibility of using them for the creation of new materials need for modern technology. For instance, REM as alloying components allows for preparation of material with special magnetic properties. A promising method for forming such coating is the surface treatment of metals. This process has an electrochemical character as such for the organization of technology the knowledge of kinetics and mechanism of these processes is important. Despite significant interest in rare-earth metals, these issues are not well described in the literature. In order to choose an adequate mathematical model for calculation of kinetic primers, preliminary experiments that allow evaluating the reversibility of the electrode process have been conducted. Based on that, it was concluded that cathodic reduction of terbium and holmium ions in equimolar NaCl-KCl melt is irreversible. By means of voltammetric analysis, kinetic parameters (transfer coefficients, heterogeneous constants of charge transfer rate) of terbium and holmium electroreduction in equimolar NaCl-KCl melt were determined. The experiment was conducted in a three-electrode cell under a purified argon atmosphere. A dependency of kinetic parameters on the concentration of terbium and holmium chlorides wt (%): 1, 3, 5, 7, 10, was determined. The experiment was conducted in 1073–1173K temperature range. Values of kinetic parameters increase with temperature but decrease with the increase of REM chloride. Based on obtained data, it was found that electroreduction of chloride complexes LnCl63– (Ln–Tb, Ho) in equimolar NaCl-KCl melt is irreversible in the studied range of temperatures and REM concentrations. In summary of experimental data, in range of temperature and rare-earth chloride concentration, and assumption was made that reduction of terbium and holmium ions occurs in two stages. The process includes the preceding stage of complex dissociation. A mechanism of LnCl63– complex reduction in the mentioned melt is proposed. The obtained results are in agreement with literate data for analogues systems

    Mechanisms of water-salt metabolism disturbances in dogs subjected to six month hypokinesia

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    Water-salt metabolism in dogs during prolonged restricted motor activity (hypokinesia) was investigated. It was found that hydration occurred and fluid was redistributed between the extra- and intra-cellular sectors. Also, electrolyte excretion rose, and magnetism and calcium metabolism changed significantly. It is concluded that the forces caused by muscle strain proper (which was decreased under conditions of hypokinesia) influence the state of bone metabolism

    Determination Of Formation Regimes For Bilayer Cobalt Dysprosium Intermetalic Surface Alloy

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    High tech industrial fields on modern development stage are in need of construction materials with an optimal ratio of volume and surface properties, along with low cost of material itself. As evidenced by studies, in order to give a set complex of properties to a workpiece that operates under specific conditions, it is often sufficient to only modify its surface area. Over the course of studies, by means of gravimetric, influence of technological parameters (temperature and time samples are kept in the melt) on specific mass change of cobalt samples, that act as substrate, during electroless diffusive saturation with dysprosium in eutectic melt of lithium and potassium chlorides have been studied. A mathematical dependency was established for specific mass change of cobalt samples on time spent in melt for temperature range of 873–973 K. Composition of intermetallic coats obtained on surface of cobalt samples was studied means of EDX and SEM analyses. It was discovered, that for chosen temperature range, diffusion layers formed on surface of cobalt samples consists of two structural zones that correspond to Co-Dy and Cp2Dy phases

    Crisis Identification and Development of Crisis Management Algorithm in the Agricultural Sector

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    The efficiency of many enterprises has declined significantly in the current global crisis. Enterprise management is the management of joint activities of people, which consists of many problems. The primary tactical tasks for most business entities are “patching holes” (or a reactive form of management) and preventing bankruptcy. This approach does not allow to achieve sustainable operation of the enterprise in the long term. Therefore, the formation of an effective mechanism for managing enterprises is acquiring special significance in today's conditions. The crisis is characterized by many interrelated situations that increase the complexity and risk of management. The problem of evaluating the effectiveness of enterprises is still one of the most complex and intractable. The crisis is objectively characterized by many interrelated situations that increase the complexity and risk of management. The crisis state of the enterprise is particularly difficult in predicting the results of management actions, since the course of events can be changed by relatively small impacts. Based on this, the company should be able to analyze both its own interests and the interests of business partners with whom the company enters into economic relations. There is such a problem as low management competence in the agricultural sector. In this regard, the development of enterprises becomes an urgent problem. This can be achieved by forming a scientifically based algorithm of actions aimed at improving the position of enterprises in the market. The subject of the study is the formation of a crisis identification system and the development of an enterprise crisis management algorithm. The theoretical and practical significance of solving problems associated with achieving sustainable development and functioning of enterprises determined the choice of goals, objectives, object and subject of this study. Based on the foregoing, the object of study is industrial (processing) agricultural enterprises. The research task is to propose a set of measures to overcome the crisis in the processing industrial enterprise. A set of measures has been proposed and justified to overcome the crisis in an industrial enterprise, which will help in managing the economic entity and the result of the implementation of this approach should be overcoming the crisis. The proposed measures can be applied not only by industrial processing enterprises, but also by other economic entities
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