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The purpose of this article is to build a mathematical model for analyzing the sustainability of the development of an enterprise in the fuel and energy complex, integrated into an information management system. It is noted that one of the strategic dominants in achieving the national goal of accelerating the technological development of any country is to ensure the effective functioning of enterprises in the fuel and energy complex. It is substantiated that these enterprises represent the basis of the material life of society, thus, ensuring their sustainable development is a significant factor for the formation of the structure of sectoral and inter-sectoral industrial complexes. In order to analyze the sustainable development of enterprises, an integral indicator is proposed, the components of which are the vectors of production, organizational, economic, environmental and social characteristics. Due to the weak structure of some characteristics, to solve the problem of their synthesis with quantitatively defined indicators, it is proposed to use the mathematical apparatus of fuzzy logic. Weakly structured indicators are formally described by linguistic variables. To establish the dependence of the integral indicator of sustainable development on production, organizational, economic, environmental and social indicators, a fuzzy-logical model has been built, which makes it possible to use the knowledge of experts by constructing rules of fuzzy inference. The fuzzy logic model is implemented using MATLAB tools. On the constructed model, experiments were carried out to assess the impact of each of the local indicators of sustainable development of an enterprise on the integral indicator. The advantage of the constructed model is its adaptability to changes in the operating conditions of enterprises.

The purpose of this article is to build a mathematical model for analyzing the sustainability of the development of an enterprise in the fuel and energy complex, integrated into an information management system. It is noted that one of the strategic dominants in achieving the national goal of accelerating the technological development of any country is to ensure the effective functioning of enterprises in the fuel and energy complex. It is substantiated that these enterprises represent the basis of the material life of society, thus, ensuring their sustainable development is a significant factor for the formation of the structure of sectoral and inter-sectoral industrial complexes. In order to analyze the sustainable development of enterprises, an integral indicator is proposed, the components of which are the vectors of production, organizational, economic, environmental and social characteristics. Due to the weak structure of some characteristics, to solve the problem of their synthesis with quantitatively defined indicators, it is proposed to use the mathematical apparatus of fuzzy logic. Weakly structured indicators are formally described by linguistic variables. To establish the dependence of the integral indicator of sustainable development on production, organizational, economic, environmental and social indicators, a fuzzy-logical model has been built, which makes it possible to use the knowledge of experts by constructing rules of fuzzy inference. The fuzzy logic model is implemented using MATLAB tools. On the constructed model, experiments were carried out to assess the impact of each of the local indicators of sustainable development of an enterprise on the integral indicator. The advantage of the constructed model is its adaptability to changes in the operating conditions of enterprises. [ABSTRACT FROM AUTHOR]

The using diesel and biodiesel blends as a fuel has been a recent field of study especially with nanoparticles additives. The addition of alumina nanoparticles to biodiesel was verified to reduce emissions, while engine performance was not given great attention to evaluate the effect of blending alumina nanoparticles with the diesel and biodiesel mixture on the performance characteristics of the diesel engine. Then performance and emission tests were carried out by using different fuel samples in a single cylinder diesel engine. The brake thermal efficiency for the alumina nanoparticles (50 ppm, 100 ppm) and biodiesel blends were lower than that of biofuel (D80B20) blends, it was decreased by 2.5 %, 6.05 % respectively as compared to the blend (D80B20). The rate of carbon monoxide emissions for the two biodiesel and alumina blends were lower than that of the biodiesel blend (D80B20) and the best reduction was for the blend (D80B20N50) and was 76.3 % as compared with the biodiesel blend (D80B20). Also, the nitrogen oxides emissions for all the blends with nanoparticles were lower than that of the blend D80B20 due to shortened ignition delay and less fuel was added during the combustion which lead to reduction in nitrogen oxides emissions. [ABSTRACT FROM AUTHOR]

Summary: The current imperative transition to environmentally friendly technologies for power generation requires the reduction of their production costs. In the case of proton exchange membrane fuel cells, current collectors, which are usually integrated as flow field plates in the cells, constitute a critical component due to its weight and cost. In this paper, a cost-effective alternative is proposed, which is based in copper as conductive substrate. The protection of this metal in the aggressive media resulting from the operation conditions is the principal challenge. A continuous reduced graphene oxide coating has been developed to avoid corrosion under operation. The results of the protection behavior of this coating under accelerated stress tests performed in a real fuel cell reveal that the cost-effective procedure for copper coating is able to compete with gold-plated nickel collectors and constitute a real alternative to reduce the production costs and the weight of these systems.

Sustainable energy from biomass is one of the most promising alternative energy sources and is expected to partially replace fossil fuels. Tobacco industries have normally rid their processing residues by landfilling or incineration, affecting the environment negatively. These residues can be used to either extract high-value chemicals or generate bio-energy via hydrothermal liquefaction. The main liquid product or bio-oil consists of highly complicated chemicals. In this work, the bio-oil from hydrothermal liquefaction of tobacco processing residues was generated in a batch reactor at biomass-to-deionized water ratio of 1:3, temperature of 310°C, and 15 min residence time, yielding the maximum liquid products for more than 50% w/w. The liquid products were analyzed, using two-dimensional gas chromatography and time-of-flight mass spectrometry (GC × GC/TOF MS). This technique allowed for a highly efficient detection of numerous compounds. From the results, it was found that hydrothermal liquefaction can cleave biopolymers (cellulose, hemicellulose, and lignin) in tobacco residues successfully. The hydrothermal liquefaction liquid products can be separated into heavy organic, light organic, and aqueous phase fractions. By GC × GC/TOF MS, the biopolymers disintegrated into low molecular weight compounds and classified by their chemical derivatives and functional groups could be detected. The major chemical derivative/functional groups found were cyclic ketones and phenols for heavy organic and light organic, and carboxylic acids and N-containing compounds for the aqueous phase. Additionally, by the major compounds found in this work, simple pathway reactions occurring in the hydrothermal liquefaction reaction were proposed, leading to a better understanding of the hydrothermal liquefaction process for tobacco residues. [ABSTRACT FROM AUTHOR]