76 research outputs found

    Diagnostics of internal combustion diesel engines operated in construction and mining

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    Mining machinery and equipment belong to the group of special machines working in extreme conditions. Mining machines are used in difficult conditions such as limited supplies of fresh air, heat from the rock, in places with high humidity and heavy dust. In other specifics related to the extraction process is brine, harmful compounds such as sulphur dioxide, or rock debris raining down. The machines are operated in continuous mode, the clock. Working in mining conditions machines are exposed to frequent breakdowns and malfunctions. Identifying of failure diesel engines can be cumbersome in these conditions and time-consuming, leading to longer downtime, thereby reducing operating efficiency and increased cost. Therefore, in the paper was a review and analysis methods for the diagnosis of internal combustion diesel engines used in machines built and used to power machines in underground mining. On the basis of diagnostic testing was performed analysis of cases occurring malfunctions and failures

    Determination of low molecular weight organic acids (LMWOAs) in environmental samples

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    This paper presents a quick method to identify and quantify ten low molecular weight organic acids in environmental samples (e.g., soil, cultivation substrate). The procedure involves extraction of the acids from the sample with a dilute acid of a pH of 2, followed by the separation and quantification of ten acids, i.e., oxalic, formic, acetic, malic, maleic, lactic, malonic, succinic, fumaric, and citric, by reversed-phase liquid chromatography (RPLC). The detection limit was in the range from 8.6 × 10-4 nM to 0.014 microM, with recovery in the range from 60 to 100%. A proven method was applied for the determination of exudate components in the king oyster mushroom (Pleurotus eryngii) post-cultivation straw substrate spiked individually with Cu2+, Co2+, Cd2+, Zn2+ and Ni2+ at 10 mM. The generation/exudation of LMWOAs was metal dependent and was strongly induced by Ni and Cd, less induced by Co and Cu, and suppressed by Zn ions. At 10 mM of Ni, the total concentration of the acids was about 6 times as high as that of the control. We can assume that particular metals alter the mycelium growth and mushroom physiology mainly through the competitive inhibition of nutrients such as Fe and Ca, and also by the inactivation of metalloenzymes, responsible for the substrate mineralization and antioxidant potential. Moreover, organic ligands do not only enhance the solubility of the trace metals, but also they reduce their toxicity to the mushroom, increasing uptake/accumulation abilities during bioremediation of soil/medium contaminated with heavy metals

    Entrance research on pressure distribution in combustion chamber of gasoline engine applied in electric generator, fuelled by syngas, for different ignition timing

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    Synthetic gas (syngas) produced form waste organic matter may be used as a fuel for internal combustion engines. Possibilities of syngas application as an independent IC engine energy carrier are limited. Designed system of energy conversion from waste to electricity is expected to produce gas consists mainly carbon monoxide, methane, hydrogen and carbon dioxide. Based on theoretical study and own research, as the main factors which impact on floating syngas composition the quality of input substance, process temperature and gasifying medium application were identified. The fluctuation of syngas composition contributes important challenge in aspect of energetic efficiency and mechanical durability of generator system. The researches were provided on research test bed, which enables pressure distribution measurement in the combustion chamber (for various mixture of synthetic gases) and correction of ignition timing. The results of the researches indicate that proper correction of the ignition advance allows syngas mixtures combustion in wide range of their composition

    The methodology of grade of gasification reactor effectivity

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    Ecology problems are addressed in all areas of engineering. Gasification is widely used methodology, which allows to power vehicles and fuel generators via alternative fuel. The more it seems important to address the issues of gasification in the group of scientists dealing with machines. In article authors present results of methodology in effectivity of gasification graduation. The base of experiment is the complimentary reactor, which was made for gasification of different materials. Gases that are achieved on the output of the system are used to supply combustion engines. In article, expect mentioned methodology, authors present reactor build and measurement (including complimentary software) system, mounted on system. The new energy supplies are still discovered. At the same time, researchers on good know substances are in progress. In article, authors are presented one of the methods of gasification reactor effectivity. Authors’ reactor has a burning chamber, and outlet circuit. Presented methodology was relayed on E-E system with software part. System is contained a few thermocouples with multiplexing ADC card for acquisition of data. All parts are presented in an article. An article is a result of progressing grant in DEMONSTRATOR+ program (no. WND-DEM-1-527/001)
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