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DESIGN ANALYSIS OF HYBRID GAS TURBINE - FUEL CELL POWER PLANT IN STATIONARY AND MARINE APPLICATIONS
PublicationThe paper concerns design analysis of a hybrid gas turbine power plant with a fuel cell (stack). The aim of this work was to find the most favorable variant of the medium capacity (approximately 50 MW) hybrid system. In the article, computational analysis of two variants of such a system was carried out. The analysis let to calculate capacity, efficiency of both variants and other parameters like flu gas temperature. The paper...
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INVESTIGATIONS OF THE EMISSION CHARACTERISTICS OF A DUAL-FUEL GAS TURBINE COMBUSTION CHAMBER OPERATING SIMULTANEOUSLY ON LIQUID AND GASEOUS FUELS
PublicationT his study is dedicated to investigations of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. As the object of the research, a low-emission gas turbine combustion chamber with partial premixing of fuel and air inside the outer and inner radial-axial swirls was chosen. The method of the research is based on the numerical solution of the system of differential...
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Methods of assaying volatile oxygenated organic compounds in effluent samples by gas chromatography—A review
PublicationThe paper is a review of the procedures for the determination of volatile and semivolatile oxygenated organic compounds (O-VOCs) in effluent samples by gas chromatography. Current trends and outlook for individual steps of the procedure for the determination of O-VOCs in effluents are discussed. The available sample preparation techniques and their limitations are described along with GC capillary columns used for O-VOCs separation...
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Load effect impact on the exploitation of concrete machine foundations used in the gas and oil industry
PublicationMachine foundations is a critical topic in the gas and oil industry, which design and exploitation require extensive technical knowledge. Machine foundations are the constructions which are intended for mounting on it a specific type of machine. The foundation has to transfer dynamic and static load from machine to the ground. The primary difference between machine foundations and building foundations is that the machine foundations...
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VOCs absorption from gas streams using deep eutectic solvents – A review
PublicationVolatile organic compounds (VOCs) are one of the most severe atmospheric pollutants. They are mainly emitted into the atmosphere from anthropogenic sources such as automobile exhaust, incomplete fuel combustion, and various industrial processes. VOCs not only cause hazards to human health or the environment but also adversely affect industrial installation components due to their specific properties, i.e., corrosive and reactivity....
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Low-energy positron scattering from gas-phase pyrimidine: A quantum treatment of the dynamics and a comparison with experiments
PublicationWe are reporting detailed quantum scattering calculations that describe the diffusion of a beam of low-energy positrons interacting with the pyrimidine target as a gas-phase partner. The calculations have employed an essentially ab initio model for the short-range correlation interaction and for the electrostatic interaction of an impinging positron and the electron+nuclear structure of the target molecule at its equilibrium geometry.
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Formaldehyde detection with chemical gas sensors based on WO3 nanowires decorated with metal nanoparticles under dark conditions and UV light irradiation
PublicationWe report results of formaldehyde gas (CH2O) detection under dark conditions and UV light irradiation with pristine tungsten trioxide nanowires (WO3 NWs) and metal nanoparticles decorated WO3 NWs gas sensing layers. The resistive layers were deposited by one step aerosol assisted chemical vapor deposition (AACVD) on commercial alumina substrates with 10-pair interdigitated platinum electrodes. The elaborated gas sensors, based...
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Monitoring the gas turbine start-up phase on the platform using a hierarchical model based on Multi-Layer Perceptron networks
PublicationVery often, the operation of diagnostic systems is related to the evaluation of process functionality, where the diagnostics is carried out using reference models prepared on the basis of the process description in the nominal state. The main goal of the work is to develop a hierarchical gas turbine reference model for the estimation of start-up parameters based on multi-layer perceptron neural networks. A functional decomposition...
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Standing Acoustic Waves and Relative Nonlinear Phenomena in a Vibrationally Relaxing Gas-Filled Resonator
PublicationStanding acoustic waves in one-dimensional resonator filled with vibrationally relaxing gas, are studied. Two regimes of excitation of molecular vibrational degrees of freedom are considered, equilibrium and nonequilibrium. The acoustic energy enlarges with time in the non-equilibrium regime and decreases otherwise before formation of discontinuity. After that, it decreases due to nonlinear absorption and tends to zero in equilibrium...
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Non-Gaussian Resistance Fluctuations in Gold-Nanoparticle-Based Gas Sensors: An Appraisal of Different Evaluation Techniques
PublicationVolatile organic compounds, such as formaldehyde, can be used as biomarkers in human exhaled breath in order to non-invasively detect various diseases, and the same compounds are of much interest also in the context of environmental monitoring and protection. Here, we report on a recently-developed gas sensor, based on surface-functionalized gold nanoparticles, which is able to generate voltage noise with a distinctly non-Gaussian...
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Qualitative characteristics and comparison of volatile fraction of vodkas made from different botanical materials by comprehensive two-dimensional gas chromatography and the electronic nose based on the technology of ultra-fast gas chromatography
PublicationBACKGROUND Vodka is a spirit-based beverage made from ethyl alcohol of agricultural origin. At present, increasingly more vodka brands have labels that specify the botanical origin of the product. Until now, the techniques for distinguishing between vodkas of different botanical origin have been costly, time-consuming and insufficient for making a distinction between vodka produced from similar raw materials. Therefore, it is...
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Study of ZrS3-based field-effect transistors toward the understanding of the mechanisms of light-enhanced gas sensing by transition metal trichalcogenides
PublicationExtending knowledge of the properties of low-dimensional van der Waals materials, including their reactivity to the ambiance, is important for developing innovative electronic and optoelectronic devices. Transition metal trichalcogenides with tunable optical band gaps and anisotropic conductivity are an emerging class among low- dimensional structures with the possibility of gate tunability and photoreactivity. These properties...
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Determination of Odor Intensity of Binary Gas Mixtures Using Perceptual Models and an Electronic Nose Combined with Fuzzy Logic
PublicationMeasurement and monitoring of air quality in terms of odor nuisance is an important problem. From a practical point of view, it would be most valuable to directly link the odor intensity with the results of analytical air monitoring. Such a solution is offered by electronic noses, which thanks to the possibility of holistic analysis of the gas sample, allow estimation of the odor intensity of the gas mixture. The biggest problem...
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Design and Thermodynamic Analysis of a Steam Ejector Refrigeration/Heat Pump System for Naval Surface Ship Applications
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Beyond the helium buffer: 12C−2 rotational cooling in cold traps with H2 as a partner gas: interaction forces and quantum dynamics
Publicationabstract = { The scattering cross-sections and corresponding rate coefficients for rotationally inelastic collisions of $^{12}$C$_2$^-$ ($^2 \Sigma_g^+$) with H$_2$ ($^1 \Sigma_g^+$) are presented over a broad range of cold-trap temperatures. They have been calculated using quantum scattering theory that employs a new ab initio potential energy surface. The rate coefficients for the inelastic processes in the anionic partner are...
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Poultry meat freshness evaluation using electronic nose technology and ultra-fast gas chromatography
PublicationTo ensure that chicken meat products are safe to consume, it is important to be able to reliably determine its shelf-life. To assess the applicability of ultra-fast gas chromatography and electronic nose technology in evaluation of poultry, an analysis of the headspace of ground chicken meat samples refrigerated over a period of 7 days was performed. Chemometric techniques were used to mine additional information from a multiparametric...
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Modeling of low calorific gas burning in a deficient oxygen environment and high-temperature oxidizer
PublicationThe experimental research will be performed using the experimental facility with a combustion chamber. The oxygen concentration in combustion oxidizers will be varied from 21% by volume (normal) air to 2%. The test combustion chamber will be fed with propane or methane as the reference fuel, then with low calorific fuels as test gases obtained by mixing various combustible components, e.g. H2, CH4, CO, and neutral gases, e.g. N2,...
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Comprehensive two-dimensional gas chromatography for determination of the terpenes profile of blue honeysuckle berries
PublicationTerpenes are the main group of secondary metabolites, which play essential role in human. The establishment of the terpenes profile of berries of different blue honeysuckle cultivars was achieved by headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (HS-SPME/GCGC-TOFMS). The berries were found to contain 44 terpenes identified by GCGC-TOFMS....
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Effect of irradiation intensity and initial pollutant concentration on gas phase photocatalytic activity of TiO2 nanotube arrays
PublicationWell-organized TiO2 nanotube arrays were fabricated via one-step anodization process. The as-prepared TiO2 nanotubes were characterized by X-ray powder diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS) and scanning electron microscopy (SEM). Photocatalytic activity of obtained photocatalyst was studied in reaction of toluene degradation in the gas phase using low powered and low...
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A natural deep eutectic solvent - protonated L-proline-xylitol - based stationary phase for gas chromatography
PublicationThe paper presents a new kind of stationary phase for gas chromatography based on deep eutectic solvents (DES) in the form of a mixture of L-proline (protonated with hydrochloric acid) as a hydrogen bond acceptor (HBA) and xylitol as a hydrogen bond donor (HBD) in a molar ratio of HBA:HBD 5:1. DES immobilized on a silanized chromatographic support was tested by gas chromatography (GC) in order to determine its resolving power for...
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Computational Fluid Dynamics Simulation of Gas–Liquid Multiphase Flow in T-junction for CO2 Separation
PublicationThe article presents the results of a computational fluid dynamics (CFD) analysis of gas-liquid multiphase flow. The simulation was conducted using CFD code and the Euler–Euler approach. The presented study relates to the non–reactive, steady-state, turbulent flow of water and carbon dioxide mixture in a 3D pipe. Separation phenomenon between phases is observed. The solution was obtained using a mixture model. Different values...
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An energetic analysis of a gas turbine with regenerative heating using turbine extraction at intermediate pressure - Brayton cycle advanced according to Szewalski's idea
PublicationIn this paper, a modification of a simple gas turbine into the Brayton cycle with regenerative heating, using turbine extraction at intermediate pressure, is presented. The main concept of the retrofitting is based on the transfer of heat from the turbine exhaust gases to the air entering the combustion chamber. The extracted gas transfers heat to air via the divided regenerative heat exchanger and after that is compressed and...
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Theoretical analysis of heat transfer between a liquid layer formed by an impinginf gas liquid jet AND a solid surface
PublicationHeat transfer phenomenon between a horizontal solid surface and a liquid layer created on a surface by an axisymmetrical liquid gas impinging jet has been analysed. The analytical treatment of the phenomenon is devoted to the area whose diameter is lower than the diameter of the hydraulic jump. W pracy przedstawiono teoretyczną analizę wymiany ciepła pomiędzy warstwą cieczy a stałą powierzchnią po której przepływa.
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Comparative analysis of thermodynamic cycles of selected nuclear ship power plants with high-temperature helium-cooled nuclear reactor
PublicationThis paper presents a comparative analysis of thermodynamic cycles of two ship power plant systems with a high-temperature helium- cooled nuclear reactor. The first of them is a gas system with recuperator , in which classical gas chamber is substituted for a HTGR reactor (High Temperature Gas-cooled Reactor) . The second of the considered cycles is a combined gas-steam system where working medium flux from gas turbine outlet...
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A headspace solid-phase microextraction method development and itsapplication in the determination of volatiles in honeys by gas chromatography
PublicationThe first part of the paper presents the detailed optimisation of all steps of the determination procedureof volatiles from Polish honeys by headspace solid-phase microextraction (HS-SPME) as the sample preparationmethod and gas chromatography/mass spectrometry (GC-MS) as the method of final determination.The methodology of semi-quantative analysis allowed the isolation and identification of volatile fractioncompounds from popular...
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Performance of cryogenic oxygen production unit with exhaust gas bleed for sewage sludge gasification and different oxygen purities
PublicationThe paper presents a thermodynamic analysis of the integration of a cryogenic air separation unit into a negative CO2 emission gas power plant. The power cycle utilizes sewage sludge as fuel so this system fits into the innovative idea of bioenergy with carbon capture and storage. A cryogenic air separation unit integrated with the power plant was simulated in professional plant engineering and thermodynamic process analysis software....
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Common methods for the chiral determination of amphetamine and related compounds I. Gas, liquid and thin-layer chromatography
PublicationThis article reviews the most common, useful methods for the chiral determination of amphetamine (AM) and AM-deriveddesigner drugs in different of matrix, including blood, hair, urine, medicaments or standard solutions, taking into considerationarticles published in the past 15 years. We consider chromatographic methods (e.g., gas, liquid, high-performance liquid, and thinlayer). We describe several types of chiral derivatization...
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Higher-Order Spectra in Nanoparticle Gas Sensors.
PublicationPrzedstawiono wyniki badań rezystancji fluktuacji w rezystancyjnych sensorach gazu wykonanych z nanocząstek Pdx(WO3)1-x dla x=0.01 oraz x=0.12. Rozkład prawdopodobieństwa obserwowanych fluktuacji wskazywał na występowanie składowej o rozkładzie różnym od rozkładu normalnego. Do jego scharakteryzowania wykorzystano spektra wyższych rzędów oraz ich przekroje.
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A nonlinear approach to modelling gas bubble deformation.
PublicationPrzedstawiono model wyjaśniający wpływ deformacji pęcherzyka na występowanie zjawiska chaosu podczas generowania pęcherzyków gazowych z pojedynczej dyszy zanurzonej w cieczy.
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Lisicon solid electrolyte electrocatalytic gas sensor
PublicationW artykule przedstawiono sposób przygotowania oraz wyniki badań elektrokatalitycznego czujnika gazów na bazie Lisicon'owego elektrolitu stałego. Przedstawiono charakterystyki czujnika w mieszaninie dwutlenku azotu oraz dwutlenku siarki w syntetycznym powietrzu. Odpowiedź I-V czujnika w unikalny sposób zależy od stężenia i rodzaju gazu w otoczeniu czujnika.
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Gas bubble dynamics - experiment and fractal analysis.
PublicationPrzedstawiono nieliniowe aspekty generowania pęcherzyków gazowych z dysz szklanych umieszczonych pod powierzchnią cieczy. W badaniach eksperymentalnych zastosowano układ laser diodowy- fotodetektor oraz hydrofon. Sygnały z fotodetektora i hydrofonu były wzmacniane, rejestrowane za pomocą karty dźwiękowej, a następnie poddane analzie fraktalnej. W wyniku obliczeń ustalono mapy występowania chaosu w funkcji strumienia objętości gazu.
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Microscopic parameters of gas via acoustic measurements
PublicationProponujemy wstępną analizę odwrotnego problemu, który sformułowano, opartą na statycznej mechanice /termodynamice, rozważającej gaz jako środek rozprzestrzeniania dzwięku.
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Chromatographic Examinations in the Gas Network Odourised by Tetrahydrothiophene
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Fractal analysis and modelling of gas bubble formation.
PublicationPrzedstawiono wyniki badań eksperymentalnych generowania pęcherzyków powietrznych z dysz o różnej średnicy, umieszczonych pod powierzchnią wody. Sygnał rejestrowany przez układ laser-fotodioda poddano analizie fraktalnej.
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Gas sensors based on functionalized carbon nanotubes
PublicationW pracy przedstawiono przegląd czujników gazów z modyfikowanych nanorurek węglowych.
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Application of ionic liquids for gas separation processes
PublicationNowym kierunkiem w procesach separacji dwutlenku węgla stało się w ostatnich latach zastosowanie cieczy jonowych. Niemierzalna prężność par i możliwość dostosowania ich właściwości czyni je idealnymi mediami zastępującymi lotne, korozyjne i toksyczne rozpuszczalniki. Ponadto ciecze jonowe wykazują niską współabsorpcję innych gazów. Dlatego też, możliwe jest selektywne odseparowanie dwutlenku węgla z mieszanin gazowych
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Staircase Voltammetry Application to Electrocatalytic Gas Sensor
PublicationW pracy przedstawiono wyniki badań czujnika elektrokatalicznego pobudzanego sygnałem schodkowym w różnych mieszaninach gazowych .
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Magnetoacoustic heating in a quasi-isentropic magnetic gas
PublicationThe nonlinear heating of a plasma which associates with the transfer of energy of magnetoacoustic waves into that of the entropy mode, is analytically studied. A plasma is uniform and motionless at equilibrium. Perturbations in a plasma are described by a system of ideal magnetohydrodynamic equations. The equilibrium straight magnetic strength and the wave vector form a constant angle which varies from 0 to π/2. There exist four...
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Electrocatalytic gas sensors based on Nasicon and Lisicon
PublicationW pracy przedstawiono porównanie właściwości czujników elektrokatalitycznych na bazie Nasiconu i Lisiconu. Czujniki zostały przygotowane w technologii ceramicznej. Przedstawiono wyniki badań czujników w obecności mieszaniny dwutlenku azotu, dwutlenku siarki i syntetycznego powietrza.
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Application of cyanated asphaltenes in gas-phase adsorption processes for removal of volatile organic compounds
PublicationThe paper presents an innovative, chemically modified (methylcyanated) asphaltene-based adsorbent that can be an inter-esting low-cost alternative for traditional adsorbents. Adsorption properties of adsorbents were examined by inverse gas chromatography technique, adsorption isotherms, and breakthrough curves. A significant increase in retention volume for pyridine, 2-pentanone, nitropropane, toluene, and 1-butanol was observed....
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A dipole-driven path for electron and positron attachments to gas-phase uracil and pyrimidine molecules: a quantum scattering analysis
PublicationElectron and positron scattering processes in the gas-phase are analysed for uracil and pyrimidine molecules using a multichannel quantum approach at energies close to threshold. The special effects on the scattering dynamics induced by the large dipole moments in both molecules on the spatial features of the continuum leptonic wavefunctions are here linked to the possible bound states of the Rydberg-like molecular anions or ‘positroned’...
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The CFD analysis of influence the start of fuel injection (SOI) on combustion parameters and exhaust gas composition of the marine 4-stroke engine
PublicationThe paper presents a theoretical analysis of the impact of injection timing on the parameters of the combustion process and the composition of exhaust gas from a 4-stroke engine designed to shipbuilding. The analysis was carried out based on a three-dimensional multi-zone model of the combustion process. This model has been prepared on the basis of properties of the research facility. The input data to the model were obtained through...
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Separation of Volatile Oxygen-containing Organic Compounds by Gas Chromatography - selectivity comparison of different polarity stationary phases
PublicationThis paper present a results of the separation of 36 reference compounds belonging to the group of Volatile Oxygen-Containing Organic Compounds (OVOCs) using capillary gas chromatography with flame ionization detector (GC-FID) and three stationary phases of different polarity. A selectivity has been studied regarding to OVOCs and n -alkanes. The most useful for the separation of the group OVOCs is a polar ionic liquid stationary...
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Highly effective asphaltene-derived adsorbents for gas phase removal of volatile organic compounds
PublicationA novel nitrated asphaltene-derived adsorbent (Asf-Nitro) was prepared using facile isolation and modification procedures. The successful modification was confirmed by Fourier-transform infrared spectroscopy (FTIR). The nitrated adsorbent was evaluated in terms of dispersive and specific interactions, Lewis acid-base properties and adsorption isotherms by means of inverse gas chromatography (IGC). Nitration was found to be extremely...
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Identification of pollutants at the adjacent areas to the landfill site using two dimensional gas chromatography with mass spectrometry technique
PublicationMunicipal landfills are considered one of the main sources of air pollutants. In this article is presented the use of a modern analytical technique: a two dimensional gas chromatography to identify the substances in the atmospheric air near a waste processing plant located in Gdansk. In order to determine the types of substances occurring in different atmospheric conditions, the study was conducted from February to April 2016....
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublicationVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublicationVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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DIAGNOSTIC INFORMATION ANALYSIS OF QUICKLY CHANGING TEMPERATURE OF EXHAUST GAS FROM MARINE DIESEL ENGINE PART I SINGLE FACTOR ANALYSIS
PublicationIn this paper, attention was paid to the problem of low controllability of marine medium- and high-speed engines during operation, which significantly limits the parametric diagnosis. The measurement of quickly changing temperature of engine exhaust gas was proposed, the courses of which can be a source of diagnostic information. The F statistic of the Fisher-Snedecor distribution was chosen as a statistical tool. Laboratory tests...
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Waste management in the mining industry of metals ores, coal, oil and natural gas - A review
PublicationWaste generated due to mining activity poses a serious issue due to the large amounts generated, even up to 65 billion tons per year, and is often associated with the risk posed by its storage and environmental management. This work aims to review waste management in the mining industry of metals ores, coal, oil and natural gas. It includes an analysis and discussion on the possibilities for reuse of certain types of wastes generated...
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Determination of β-blockers and β-agonists using gas chromatography and gas chromatography–mass spectrometry – A comparative study of the derivatization step
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