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Research ArticleView abstract PDF Full textNitrogen dioxide, carbon dioxide and sulphur dioxide are acidic gas and they produce corrosive medium for copper sculptures. These gases absorb moisture to form nitric acid, carbonic and sulphuric acid. It forms corrosion cell on the surface of copper and accelerate corrosion reactions. The corrosion cell formation is written as: Cu|Cu2+||H+|H2 thus corrosion reactions start, and copper is oxidized into Cu2+surface and it is oxidized into Cu2+ whereas H+ ion is reduced into H2...... ReadMore
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Research ArticleTechnology For Improving Power Quality and Reducing Its Losses in Existing 0.38 кV Electric NetworksView abstract PDF Full textLow-voltage electrical networks operate under conditions of significant currents and voltages unbalanced which leads to a significant distortion of the electrical energy quality standards, as well as to an increase in its additional losses...... ReadMore
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Research ArticleView abstract PDF Full textGeopolymer is an alkaline activating material composed of aluminosilicates with interesting physical and chemical properties, it can be a more sustainable alternative to cements. Based on a methodology adapted from the ABNT NBR 16,738 standard, 3 parts of sand and variable parts of water were mixed with metakaolin and 1:5 weight ratio of powder activator (sodium hydroxide to sodium silicate)...... ReadMore
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Research ArticleView abstract PDF Full textIn 1900, Henri Poincaré noticed that the radiation energy has a mass m, equal to the energy divided by the square of the speed of light: m = E/c2. Later this relationship used by Einstein in his work on the principle of relativity. Since then, the claim that the mass can generate energy and vice versa has been called “The principle of the equivalence of mass and energy,” and became a fundamental, which prohibit criticism...... ReadMore
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Research ArticleView abstract PDF Full textRenewable energy sources especially wind energy have gained much attention due to the recent energy crisis and the desire to obtain clean energy. Due to vibration, small wind turbines are usually not installed on the structures since the vibration of a wind turbine tower can attain resonance. Resonance is often a contributing factor to many of the vibration problems that occur in wind turbine tower. Small wind turbine exists on National Centre for Energy and Environment, University of Benin with power of 1.0 kW, which creates more vibration on running condition. By reducing vibration in the wind turbine, vibration transformation on the structure will also be avoided so that we can improve performance, lifetime and power quality of wind turbine. Vibration analysis on the small wind turbine model was carried out by per..... ReadMore
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Short CommunicationView abstract PDF Full textOne of the problems arising in the analysis of nonlinearly deformable structures by the finite element method is the acceleration of the convergence of step-iterative procedures. In this paper, a method for convergence accelerating is considered, based on the use of both static and energy correction of the solution...... ReadMore
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Review ArticleView abstract PDF Full textThe socio-economic development of any society, the transformation of human capital as a result of practical actions are directly related to the activities of steadily growing sectors of the economy, starting, first of all, with micro-resources and small infrastructures of the same region, territory. In particular, along with such resources, today the need for sustainable development of the electric power industry, the energy sector has become a need of the time. Optimization of energy efficiency and consumption, which is safe and cost-effective, has become one of the main and urgent problems in international circles in recent years. The reason is that today, in the context of globalization, the economic and social integration of the energy industry is taking place all over the world, the need for which is rapidly increasing, a..... ReadMore
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Review ArticleView abstract PDF Full textIndustrialists are interested in sunflower oils of the oleic variety (Rasor et al. 2014) because of the presence of a majority content of monounsaturated fatty acids, which consider partly the resistance to oxidation of the oil for food use and on the other hand give the profile of its nutritional value (Morin and Pagès-Xatart-Parès, 2012). Various conventional processing techniques are used to extract and then refine oilseed oil (Lamas et al., 2014). Oil extracted by mechanical press or solvent is called crude oil and contains a number of impurity compounds directly defining the aroma, color, appearance, shelf life, storage of oil, texture, and smell. In fact, the refining of oil extracted by pressing (Tasan et al., 2011) is becoming increasingly important because of the huge vegetable oil market, with different cultures and communitie..... ReadMore