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Thermodynamic Cycle Concepts for High-Efficiency Power Plans. Part A: Public Power Plants 60+
PublicationAn analysis was carried out for different thermodynamic cycles of power plants with air turbines. Variants with regeneration and different cogeneration systems were considered. In the paper, we propose a new modification of a gas turbine cycle with the combustion chamber at the turbine outlet. A special air by-pass system of the combustor was applied and, in this way, the efficiency of the turbine cycle was increased by a few points....
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Dispersive liquid-liquid microextraction combined with gas chromatography–mass spectrometry for in situ determination of biogenic amines in meat: Estimation of meat's freshness
PublicationA dispersive liquid-liquid microextraction (DLLME) gas chromatography–mass spectrometry (GC–MS) technique was developed for the determination of selected biogenic amines (BAs) in samples of poultry, pork and beef. Prior to the extraction process, an appropriate volume of sodium hydroxide solution was added to each of the portioned samples. Next, samples were homogenized, centrifuged and finally sonicated at an increased temperature....
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Solid phase microextraction–comprehensive twodimensional gas chromatography–time-of-flight mass spectrometry: a new tool for determining PAHs in airport runoff water samples
Publicationfundamental aspect of airport operations is the pollution caused by airport runoff waters. Polycyclic aromatic hydrocarbons (PAHs) are one of the most important groups of xenobiotics which are commonly found in runoff water originating from airports. Only very limited data on the analysis of airport runoff water have been published until now. Therefore, a reliable and accurate analytical method based on headspace solid-phase microextraction...
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Evaluation of Terpene Decomposition in Kaffir Lime Juice during Storage Using Gas Chromatography–Mass Spectrometry and Proton Transfer Reaction–Mass Spectrometry
PublicationKaffir lime juice, often treated as production waste, can be a good source of terpenes. These compounds undergo various decomposition processes under the influence of external factors, especially during transportation and storage. In this paper, it was possible to monitor changes in the terpene profile of kaffir lime juice under different storage conditions, namely, 4 ◦C, 20 ◦C, and 35 ◦C. The identification of key decomposition...
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Comparative analysis of the theoretical models of ideal propulsor, ideal fluid brake, ideal screw propeller and ideal axial wind turbine
PublicationThe article presents a detailed discussion of four different fluid dynamics devices.These devices are presented with all relevant mathematical formulae regarding the forces, the power and the efficiency. It is demonstrated that application of the Betz theorem to axial wind turbines is not correct and it underestimates the maximujm achievable efficiency. This conclusion is supported by numerical calculations.
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An analysis of the possibilities of increasing the production of electrical energy during the summer season by heat-generation back pressure turbine power units.
PublicationZbadano możliwości podniesienia mocy elektrycznej produkowanej przez przeciwprężne bloki ciepłownicze w sezonie letnim. Zbadano jedną z możliwości polegającą na dochładzaniu wody sieciowej powracającej z aglomeracji miejskiej. Zwrócono uwagę na aspekty techniczne, ekonomiczne i ekologiczne rozważanego rozwiązania.
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The influence of rotor-stator axial gap on the aerodynamic forces generatedin the shroud clearance of a turbine stage. Part I: Pressure field
PublicationPrzedstawiono wyniki badań doświadczalnych wpływu zmiany luzu osiowego na rozkład ciśnienia w uszczelnieniu nadbandażowym stopnia powietrznej turbiny modelowej. Wykazano, że w przypadku uszczelnienia promieniowego zmiana luzu osiowego nieznacznie zmienia rozkład ciśnienia w szczelinie nadbandażowej w porównaniu ze zmianą mimośrodowości czy skośnego ustawienia osi wirnika względem osi korpusu.
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The influence of rotor-stator axial gap on the aerodynamic forces generatedin the shroud clearance of a turbine stage. Part II: Forces and moments
PublicationPrzedstawiono wyniki badań doświadczalnych wpływu zmiany luzu osiowego na wymuszenia aerodynamiczne powstające w uszczelnieniu nadbandażowym stopnia powietrznej turbiny modelowej. Wykazano, że w przypadku uszczelnienia promieniowego zmiana luzu osiowego odgrywa niewielką rolę w generowaniu sił i momentów aerodynamicznych w szczelinie nadbandażowej w porównaniu ze zmianą mimośrodowości czy skośnego ustawienia osi wirnika względem...
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Hardening of (Pb,Cd)Te Crystal Lattice with an Increasing CdTe Content in the Solid Solution
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Low Ambient Temperature Cold Start Emissions of Gaseous and Solid Pollutants from Euro 5 Vehicles featuring Direct and Indirect Injection Spark-Ignition Engines
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Thermodynamic Cycle Concepts for High-Efficiency Power Plants. Part B: Prosumer and Distributed Power Industry
PublicationAn analysis was carried out for different thermodynamic cycles of power plants with air turbines. A new modification of a gas turbine cycle with the combustion chamber at the turbine outlet has been described in the paper. A special air by-pass system of the combustor was applied, and in this way, the efficiency of the turbine cycle was increased by a few points. The proposed cycle equipped with an effective heat exchanger could...
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Understanding the early-stage release of volatile organic compounds from rapeseed oil during deep-frying of tubers by targeted and omics-inspired approaches using PTR-MS and gas chromatography
PublicationDuring deep-frying, a plethora of volatile products is emitted with the fumes. These compounds could act as oil quality indicators and change the indoor air composition leading to health risks for occupants. The presented experiments focus on deep-frying of different tubers in rapeseed oil at different frying temperatures. Here, two scenarios for real-time monitoring of volatile organic compounds (VOCs) using proton transfer reaction...
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Evaluation of the influence of the opening pressure of a marine Diesel engine injector on the results of numerical simulation of the working cycle and their comparison with the results of the laboratory experiment
PublicationThe article presents the results of a numerical simulation of the working process carried out in a diesel engine. In the applied utility program DIESEL-RK, the laboratory engine Farymann Diesel type D10 was implemented. A selected inoperability of its functional fuel supply system - reduced opening pressure of the injector pinj - was introduced. The values of adequate diagnostic parameters were determined: working gas temperature...
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Nowoczesne metody termochemicznej konwersji biomasy w paliwa gazowe, ciekłe i stałe = Modern methods of thermochemical biomass conversion into gas, liquid and solid fuels
PublicationBiomass utilization through direct- or co-combustion with coal, based on coal, hydrogen and oxygen compounds chemical energy conversion into heat in boilers, is simultaneously the cheapest and - according to experts - economically least effective solution. In case of heat and electricity production in cogeneration process in biomass fueled heat and power stations (wood, straw, energetic plants, RDF etc), investment costs are little...
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Application of static headspace gas chromatography for routine analysis of VFAs in cattle farm wastewater
PublicationOznaczanie lotnych kwasów tłuszczowych w próbkach środowiskowych jest tematem coraz powszechniej analizowanym z uwagi na ich uciążliwość w środowisku. Celem pracy było wykorzystanie techniki statycznej analizy headspace (HS) w połączeniu z analizą chromatograficzną do oznaczania lotnych kwasów monokarboksylowych w wodnych próbkach środowiskowych pochodzących z hodowli bydła.
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Multidimensional Gas Chromatography in Essential Oil Analysis. Part 2: Application to Characterisation and Identification
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Comprehensive two-dimensional gas chromatography-mass spectrometry: Recent evolution and current trends
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Essential-Oil Analysis of Irradiated Spices by Using Comprehensive Two-Dimensional Gas Chromatography
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Analysis of essential oils through comprehensive two-dimensional gas chromatography: General utility
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Headspace Liquid-Phase Microextraction of Chlorobenzenes in Soil with Gas Chromatography-Electron Capture Detection
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ChemInform Abstract: Modern Methods of Thermochemical Biomass Conversion into Gas, Liquid and Solid Fuels
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Use of Impedance Spectroscopy to Characterize Lining Performance in Simulated Flue Gas Desulfurization Systems
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Trust in the source of received information as a factor related to public perception of shale gas drilling
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Barium boron aluminum silicate glass system for solid state optical gas sensors
PublicationRecent increasing demand for new eco-friendly materials and for low cost fabrication process for use in optical sensors field, raise concern about alternative materials for this application. We have designed two glass-ceramics compositions from the quaternary ROAl2O3- SiO2-B2O3(R=Ba) alkali-earth aluminum silicate system, labeled B72 and B69, with high refractive index (>1.6), large values of Abbe number (94.0 and 53.0, respectively),...
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Evaluation of the usefulness and optimization of the separation conditions in Empty Column Gas Chromatography (EC-GC)
PublicationDotychczasowe badania wykazały, że możliwe jest rozdzielanie wysokowrzących mieszanin techniką chromatografii gazowej z zastosowaniem pustej rurki kapilarnej z topionej krzemionki, zamiast kolumn zawierających fazę stacjonarną. Operacja rozdzielania chromatograficznego ma miejsce jedynie na zasadzie różnicy temperatur wrzenia rozdzielanych substancji. Wysoki stopień podobieństwa warunków rozdzielania, osiąganych w ten sposób, z...
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Inert gas condensation made bimetallic FeCu nanoparticles - plasmonic response and magnetic ordering
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Magnetoacoustic Heating of Plasma Caused by Periodic MagnetosoundPerturbations with Discontinuities in a Quasi-Isentropic Magnetic Gas
PublicationThe magnetoacoustic heating of plasma by harmonic or periodic saw-tooth perturbations at a trans-ducer is theoretically studied. The planar fast and slow magnetosound waves are considered. The wavevector may form an arbitrary angleθwith the equilibrium straight magnetic field. In view of variableθand plasma-β, the description of magnetosound perturbations and appropriate magnetosound heatingis fairly difficult. The scenario of...
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Signals features extraction in radioisotope liquid-gas flow measurements using wavelet analysis
PublicationKnowledge of the structure of a flow is significant for the proper conduct of a number of industrial processes. In this case, a description of a two-phase flow regimes is possible by use of the time-series analysis in time, frequency and state-space domain. In this article the Discrete Wavelet Transform (DWT) is applied for analysis of signals obtained for water-air flow using gamma ray absorption. The presented method was illustrated...
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Influence of ethylene glycol on CaCO3 particles formation via carbonation in the gas-slurry system
PublicationStrącanie węgalnu wapnia przebiegało w układzie gaz-zawiesina w reakcji wodorotlenku wapnia z dwutlenkiem węgla. Proces precypitacji był prowadzony w obecności glikolu etylenowego. Użyty dodatek organiczny zmieniał lepkość mieszaniny reakcyjnej oraz rozpuszczalność dwutlenku węgla i węgalnu wapnia, co miało wpływ na warunki precypitacji CaCO3. Wzrost stężnia glikolu etylenowego w mieszaninie reakcyjnej powodował większe zużycie...
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Determination of solvents residues in vegetable oils and pharmaceuticals by headspace analysis and capillary gas chromatography.
PublicationPrzedstawiono wyniki zastosowania techniki analizy fazy nadpowierzchniowej w połączeniu z kapilarną chromatografią gazową do oznaczania wybranych rozpuszczalników organicznych w próbkach olejów jadalnych i produktów farmaceutycznych. Oznaczane rozpuszczalniki to: benzen, toluen, heksan oraz chlorowcopochodne węglowodorów alifatycznych. Opracowaną procedurę poddano walidacji. Wyznaczono granicę wytrzymalności, oznaczalności, liniowość...
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Development and evaluation of headspace gas chromatography method for the analysis of carbonyl compounds in spirits and vodkas
PublicationPrzedstawiono wyniki oznaczania związków karbonylowych (po przeprowadzeniu w pochodne przy użyciu odczynnika derywatyzującego - o-PFBHA) przy wykorzystaniu techniki analizy fazy nadpowierzchniowej w połączeniu z chromatografią gazową i detektorem wychwytu elektronów(ECD). Przedstawiono optymalizację metodyki oraz wyniki uzyskane podczas próbek rzeczywistych wybranych wyrobów spirytusowych.
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High temperature air/steam gasification of biomass in view of hydrogen rich gas production.
PublicationArtykuł przedstawia opis nowej i zaawansowanej metody konwersji termochemicznej biomasy i miejskich odpadów stałych w paliwo gazowe, bogate w wodór. W porównaniu z tradycyjnym procesem gazyfikacji, w metodzie tej wykorzystuje się powietrze/parę wodną przegrzane do wysokiej temperatury (powyżej 1300 st. C). Przegrzanie powietrza lub pary wodnej odbywa się z zastosowaniem ceramicznego przegrzewacza wysokotemperaturowego. W celu...
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Hydrogen rich gas production from high temperature air/steam gasification of biomass
PublicationW pracy przedstawiono nowoczesną technikę konwersji biomasy oraz stałych odpadów komunalnych w celu produkcji paliwa gazowego bogatego w wodór. Opisany proces gazyfikacji przebiega w wysokiej temperaturze przy obniżonej koncentracji tlenu i udziale pary wodnej. Dzięki temu możliwa jest produkcja gazów palnych, w szczególności H2, który można wykorzystać do produkcji energii elektrycznej i cieplnej.
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Reliability of flue gas desulphurisation installations - the essential condition of efficient air pollution control
PublicationW celu minimalizacji niekorzystnego wpływu SO2 i SO3 na środowisko naturalne w wielu instalacjach skrubery odsiarczające gaz spalinowy (FGD) stosowane są do usuwania tlenków siarki z gazów wylotowych. Ostre warunki pracy skruberów i dodatkowego osprzętu powodują problemy korozyjne w powszechnie stosowanych materiałach konstrukcyjnych a awarie wywierają długookresowy wpływ na środowisko. Opisano najnowsze doświadczenia związane...
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Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography
PublicationIn this paper the latest advances in the determination of volatile organic compounds using solvent-free extraction techniques in the sample preparation step are presented. A paper is focus mainly on one of the most popular sample preparation technique: solid-phase microextraction technique (SPME) combined with different detection systems and its applications to sampling of VOCs from the samples with different matrices. This paper...
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Problem of proper decomposition and initialization of acoustic and entropy modes in a gas affected by the mass force
PublicationThe relations connecting perturbations specific for acoustic and entropy modes in an accelerated fluid or in a fluid affected by constant mass force, are derived. They allow to decompose the total vector of perturbations and the overall energy into acoustic and non-acoustic parts uniquely at any instant. In order to do this, three quantities are required, for example total perturbations in entropy, pressure and velocity. The evaluations...
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Piecewise continuous distribution function method: Fluid equations and wave disturbances at stratified gas
PublicationUkład równań typu hydrodynamicznego dla warstwowych gazów w polu grawitacyjnym pochodzi od równania BGK metodą częściowej ciągłej funkcji dystrybucji. Otrzymany system równań uogólnia układ Naviera-Stokesa w dowolnych liczbach Knudsena. Rozwiązania WBK dla ultradźwięku wprowadza się w przypadku stratyfikacji exponecjalnej.
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A simple gas chromatograph for educational purposes = Prosty chromatograf gazowy do celów dydaktycznych
PublicationOpisano prosty chromatograf gazowy zaprojektowany specjalny do celów dydaktycznych, oraz serię doświadczeń laboratoryjnych z wykorzystaniem tego instrumentu w celu nauczania podstaw chromatografii studentów chemii analitycznej.
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Radioisotope measurement of selected parameters of liquid-gas flow using single detector system
PublicationTo determine the parameters of two-phase flows using radioisotopes, usually two detectors are used. Knowing the distance between them, the velocity of the dispersed phase is calculated based on time delay estimation. Such a measurement system requires the use of two gamma-ray sealed sources. But in some situations it is also possible to determine velocity of dispersed phase using only one scintillation probe and one gamma-ray source....
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Gas Composition Influence on the Properties of Boron-Doped Diamond Films Deposited on the Fused Silica
PublicationThe main subject of this study are molecular structures and optical properties of boron-doped diamond films with [B]/[C] ppm ratio between 1000 and 10 000, fabricated in two molar ratios of CH 4 -H 2 mixture (1 % and 4 %). Boron-doped diamond (BDD) film on the fused silica was presented as a conductive coating for optical and electronic purposes. The scanning electron microscopy images showed homogenous and polycrystalline surface...
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Furan Fragmentation in the Gas Phase: New Insights from Statistical and Molecular Dynamics Calculations
PublicationWe present a complete exploration of the different fragmentation mechanisms of furan (C4H4O) operating at low and high energies. Three different theoretical approaches are combined to determine the structure of all possible reaction intermediates, many of them not described in previous studies, and a large number of pathways involving three types of fundamental elementary mechanisms: isomerization, fragmentation, and H/H2 loss...
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Determination of parent and methylated polycyclic aromatic hydrocarbons in water samples by dispersive liquid–liquid microextraction–two dimensional gas chromatography–time-of-flight mass spectrometry
PublicationPolycyclic aromatic hydrocarbons (PAHs) are contaminants frequently found in environmental waters. Owing to their toxic effects, it is important to develop analytical methodologies that allow their fast and reliable determination. Dispersive liquid–liquid microextraction (DLLME) allows a quick extraction of analytes with little organic solvent consumption. The best results regarding sample preparation are obtained when 40 mL of...
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An in situ derivatization – dispersive liquid–liquid microextraction combined with gas-chromatography – mass spectrometry for determining biogenic amines in home-made fermented alcoholic drinks
PublicationA novel dispersive liquid–liquid microextraction (DLLME) gas chromatography mass-spectrometry(GC–MS) method was developed for the determination of 13 biogenic amines in home-made wine sam-ples. The method allows to simultaneous extraction and derivatization of the amines providing a simpleand fast mode of extract enrichment. During the study, two different procedures were examined. Sta-tistical analysis was performed to choose...
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Application of dispersive liquid-liquid microextraction and gas chromatography with mass spectrometry for the determination of oxygenated volatile organic compounds in effluents from the production of petroleum bitumen
PublicationWepresent a new procedure for the determination of oxygenated volatile organic compounds in samples of postoxidative effluents from the production of petroleum bitumens using dispersive liquid–liquid microextraction and gas chromatography with mass spectrometry. The eight extraction parameters were optimized for 43 oxygenated volatile organic compounds. The detection limits obtained ranged from 0.07 to 0.82 g/mL for most of the...
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Application of dynamic headspace and gas chromatography coupled to mass spectrometry (DHS-GC-MS) for the determination of oxygenated volatile organic compounds in refinery effluents
PublicationThe paper presents a new procedure for the determination of oxygenated volatile organic compounds (O-VOCs) in postoxidative effluents from the production of petroleum asphalt using dynamic headspace coupled to gas chromatography-mass spectrometry in the selected ion monitoring (SIM) mode (DHSGC-MS). Among the GC capillary columns tested, a polar SLB-IL111 column with the ionic liquid stationary phase was found to be superior due...
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Application of neural networks for identification of forcedness having effect on magnitude of turbine rotor vibration using pressure distribution in blade tip clearance.
PublicationW pracy sprawdzono, czy zastosowanie sieci neuronowych umożliwia identyfikację wymuszeń powstających w wyniku funkcjonowania maszyny jak i zależnych od jej stanu mechanicznego przy zastosowaniu rozkładu ciśnienia w uszczelnieniu nadbandażowym. Przeprowadzono pomiary rozkładu ciśnienia dla różnych warunków pracy, uwzględniając zmianę mimośrodu oraz zmianę skośnego ustawienia osi wirnika względem osi korpusu. Dokonano analiz przy...
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3D calculations of aerodynamic forces causing self-excited vibrations of turbine rotor systems. Part I: Shroud seal flow inwestigations
PublicationOpisano numeryczną i doświadczalną metodę badania przepływu w uszczelnieniu nadbandażowym stopnia turbinowego. Badania numeryczne przeprowadzono programem Fluent, a badania doświadczalne wykonano na powietrznej turbinie modelowej. Uwzględniono niesymetryczny rozkład szczeliny nadbandażowej na skuteknie centrycznego położenia osi wirnika względem osi cylindra. Zamieszczono przykładowe wyniki.
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Silica-Based Ionogels: Nanoconfined Ionic Liquid-Rich Fibers for Headspace Solid-Phase Microextraction Coupled with Gas Chromatography–Barrier Discharge Ionization Detection
PublicationIn this work, hybrid silica-based materials with immobilized ionic liquids (ILs) were prepared by sol–gel technology and evaluated as solid-phase microextraction (SPME) fiber coatings. High loadings of the IL 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide ([C4MIM][TFSI]) were confined within the hybrid network. Coatings composition and morphology were evaluated using scanning electron microscopy and energy dispersive...
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Experiments on compression ignition engine powered by nano-fuels
PublicationThe use of nanoparticles in fuels provides new opportunities for modification of fuel properties, which may affect the operational parameters of engines, in particular the efficiency and fuel consumption. The paper presents comparison of compression ignition engine performance fuelled with neat diesel and nano-diesel. Alumina (Al2O3) was used as nanoparticles. Surface-active substances, including Span 80 surfactant, as well as...
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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublicationSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...