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Liquid crystal technique application for heat transfer investigation inafin-tube heat exchanger element
PublikacjaPublikacja przedstawia rezultaty prac autorów w zakresie wykorzystania techniki ciekłokrystalicznej w badaniach wymiany ciepła dla elementów wymiennika ciepła. Technika ta z powodzeniem została zastosowana do analizy sposobu zabudowy wymiennika na jego efektywność.
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On the theory and numerical simulation of acoustic and heat modes interaction in a liquid with bubbles: acoustic quasi-solitons
PublikacjaTeoria rzutowania zaburzenia ogólnego na mody. Zastosowanie metody do badań układu równań typu Korteweg`a-de Vries`a. Rozwiązania analityczne i simulacje numeryczne.
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Experimental and numerical simulations of flow and heat transfer in heatexchanger elements using liquid crystal thermography.
PublikacjaPrzedstawienie koncepcji badań eksperymentalnych i numerycznych oraz ich wyników podczas wymiany ciepła w modelach klasycznych i płytowych wymienników ciepła w warunków przepływów przejściowych i turbulentnych.
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High-performance liquid chromatography in group-type separation and technical or process analytics of petroleum products
PublikacjaW pracy dokonano przeglądu i poddano krytycznej ocenie metody oznaczania składu grupowego produktów naftowych o różnej lotności, zarówno metody znormalizowane, jak i opisane w literaturze naukowej. W zdecydowanej większości są to metody wykorzystujące technikę chromatografii cieczowej w układzie faz normalnych (NP-HPLC). Na podstawie danych z literatury oraz własnych studiów i badań należy stwierdzić, że im wyższy zakres temperatury...
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On the new possibility of applying oscillating liquid membrane systems for melecular recognition substances responsible for taste.
PublikacjaSugerowano wczesniej, że układy osylacyjne z membraną ciekłą mogą być uzyte do opracowania sensora smaku. zbadano wpływ substancji odpowiedzialnych za smak należacych do czterech klas samku na charakterystyki osylacyjne oscylatora z mambrana ciekłą i kationowym surfaktantem chlorkiem benzylodimetylotetradecyloamonionowym. Wykazano,że niezaleznie od natury rozpuszczalnika organicznego w membranie ciekłej charkterystyki oscylacyjne...
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Comparison of noise reduction methods in radiometric correlation measurements of two-phase liquid-gas flows
PublikacjaTwo-phase liquid-gas flows occur frequently in the mining, energy, chemical, and petrochemical industries. One of non-contact methods used to analyse these flows is the gamma ray absorption method. However, the signals received from radiation detectors contain a significant stochastic noise, which makes them difficult to analyse. The article describes four methods of noise reduction in cross-correlation measurements of water-air...
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The use of liquid crystal thermography TLC and particle image velocimetry PIV in selected technical applications
PublikacjaNowadays, the energy cost is very high and this problem is carried out to seek techniques for improvement of the aerothermal and thermal (heat flow) systems performances in different technical applications. The transient and steady-state techniques with liquid crystals for the surface temperature and heat transfer coefficient or Nusselt number distribution measurements have been developed. The flow pattern produced by transverse...
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Study of pH and temperature effect on lipophilicity of catechol-containing antioxidants by reversed phase liquid chromatography
PublikacjaLipophilicity of selected antioxidant phytochemicals, including flavonoids, phenolic acids and xanthonoids, was determined by reversed phase high performance liquid chromatography with UV detection (RP-HPLC-UV). The analyses run at different temperature and pH conditions in isocratic mode suggested that lipophilicity as distribution coefficient (logD) between aqueous and organic phase decreases with increasing temperature. For...
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New type of repeated Si–C-podand catalysts for solid–liquid phase transfer reactions
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Acute and subacute (28-Day) toxicity studies of ionic liquid, didecyldimethyl ammonium acesulfamate, in rats
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The application of gradient reversed-phase high-performance liquid chromatography to the pKa and determination of polyprotic analytes
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Thermal visualization of Ostwald-de Waele liquid in wavy trapezoidal cavity: Effect of undulation and amplitude
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Mobility and biodegradability of an imidazolium based ionic liquid in soil and soil amended with waste sewage sludge
PublikacjaSorption on solids and biodegradation are main phenomena that can mitigate the pollution of soil and water by ionic liquids (ILs). ILs sorbed on soil particles become immobilized (temporarily or permanently) which prevents them from spreading into deeper layers of soil or groundwater but which also makes them less bioavailable. In this study we attempt to examine if amendment of soil with waste sludge has a potential to mitigate...
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Uncertainty of antioxidant profiling in complex mixtures using liquid chromatography involving post-column derivatisation
PublikacjaThe main goal of this paper is to discuss the problems associated with antioxidant profiling in complex samples using a high-throughput HPLC system coupled with post-column derivatisation reactor. Based on the experimental data reported in the literature, we demonstrated that improper optimisation of temperature and/or pH assay conditions performed using an on-line derivatisation reactor may substantially change the antioxidant...
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Comprehensive methodology for Staphylococcus aureus lipidomics by liquid chromatography and quadrupole time-of-flight mass spectrometry
PublikacjaStaphylococcus aureus is a common pathogen known to cause relatively minor infections as well as severe disorders in humans. Although there is fair amount of published data concerning various aspects of its biology, epidemiology, genetics, etc., there is still a scarce amount of data presenting reliable and thorough investigations regarding high-throughput analysis of total S. aureus lipid content. Therefore, the aim of this study...
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Peculiar hydrogen bonding behaviour of water molecules inside the aqueous nanochannels of lyotropic liquid crystals
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New chiral discotics with helical organization of the mesophase—liquid crystalline derivatives of dibenzotetraaza[14]annulene
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Dielectric and electro-optic studies of a bimesogenic liquid crystal composed of bent-core and calamitic units
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Distortions in structures of the twist bend nematic phase of a bent-core liquid crystal by the electric field
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Adaptive resolution simulation of liquid para-hydrogen: testing the robustness of the quantum-classical adaptive coupling
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A model of liquid film breakdown formed due to impingement of a two-phase jet on a horizontal surface
PublikacjaThe present work aims to provide an explanation to the phenomenon of breakdown of the thin liquid film created by impinging two-phase, liquid-gas jet. Existing in the literature models describe merely thebreakdown of single phase liquid films. The model presented here is based on examination of mass and energy equations under the applied criterion of the minimum of total energy. That allows to determinethe minimum thickness of...
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Determination of high-intensity sweeteners in beverages by high-performance liquid chromatography with mass spectrometry detection.
PublikacjaThe objective of the present study was to measure the concentration of nine high intensity sweeteners (acesulfame-K, aspartame, alitame, cyclamate, dulcin, neohesperidin dihydrochalcon, neotame, saccharin and sucralose) in different types of beverages available on the polish market. The proposed methodology reported here consists of a extraction with buffer composed of formic acid and N,N-diisopropylethylamine (pH 4.5) followed...
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Determination of isoprostanes in exhaled breath condensate samples by liquid chromatography coupled with tandem mass spectrometry
PublikacjaOxidative stress (OS) is a state of imbalance between continuously generating reactive oxygen species (ROS) during normal cell metabolism and mechanism of detoxifying oxygen radicals through a network of antioxidative enzymes. Isoprostanes are prostaglandin -like substances that are produced in vivo primarily by free radical-induced peroxidation of arachidonic acid. The measurement of isoprostanes in biological fluids and/or tissue...
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A research on the optimal conditions for separation and identyfication of the components from the Droseraceae extracts by column liquid chromatography
PublikacjaThe isolation of the components with anticipated biological properties i.e. antimicrobial, fungicidal, antioxidant and perhaps anticancer activity is for many years a one of the biggest issues of modern separation science. Their obtaining based on the isolation of the components with the biological activity from in vitro cultured plants by extraction techniques is often more difficult than their production by the chemical synthesis.The...
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Lipophilicity data for some preservatives estimated by reversed-phase liquid chromatography and different copmutation methods
PublikacjaW pracy przedstawiono wyniki badań właściwości chromatograficznych wybranych 12 związków z grupy kopnserwantów. Lipofilowy charakter tych związków był oceniany na podtsawie różnych parametrów retencyjnych (log Kw, log K i inne. Zastosowano narzędzie chemometryczne do zbadania korelacji występujących pomiędzy tymi parametrami retencji chromatogfraficznej.
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The lipophilicity indices of flavonoids estimated by reversed-phase liquid chromatography using different computation methods
PublikacjaDo oceny właściwości chromatograficznych wybranych flawonoidów zastosowano wyskokosprawną chromatografię cieczową z odwróconym układem faz i kolumnami chromatograficznymi typu C-8 i C-18.Lipofilowość wyrażono za pomocą różnych deskryptów lipofilowości.
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Studies on the utilization of post-distillation liquid from Solvay process to carbon dioxide capture and storage
PublikacjaIn this work, a method of precipitated calcium carbonate production from the post-distillation liquid created in the Solvay process and waste carbon dioxide was proposed and investigated. Precipitation was carried out in a model solution of calcium chloride containing ammonia at various molar ratios in relation to Ca2+ ions, while gaseous carbon dioxide was supplied to the reactor as a pure gas or as a mixture with air. It was...
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Effectiveness of toluene separation from gas phase using supported ammonium ionic liquid membrane
PublikacjaAmmonium ionic liquids (ILs) are relatively cheap in synthesis and environmentally benign and despite that they have been very rarely used in gas separation. In this research we used several ammonium ILs as liquid membranes for removal of residual toluene from gas phase. Ionic liquids used in this study were composed of bis(trifluoromethylsulfonyl)imide anion [Tf2N] and trimethylbutylammonium [N1114], trietylbutylammonium [N2224],...
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Membrane distillation assisting food production processes of thermally sensitive food liquid items: a review
PublikacjaPhysical separation technologies have become important tool for processing in the current food manufacturing industries, especially for the products containing bioactive compounds thanks to their health benefits in costumers. As for the processing of bioactive food ingredients implies the implementation of integrated systems oriented to their separation, fractionation, and recovery. In this field, membrane distillation (MD), which...
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Computational Fluid Dynamics Simulation of Gas–Liquid Multiphase Flow in T-junction for CO2 Separation
PublikacjaThe 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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Thermal visualization of Ostwald-de Waele liquid in wavy trapezoidal cavity: Effect of undulation and amplitude
PublikacjaThe present study is concerned with the numerical simulations of Ostwald-de Waele fluid flow in a wavy trapezoidal cavity in the presence of a heated cylinder situated at the center of the cavity. The work consists in characterizing the mixed convection as a function of the intensity of heat flow. The flow behaviour and temperature distribution in a cavity are the main focus of this study. The lower wall of the cavity is fixed...
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Influence of addition of carbon nanotubes on rheological properties of selected liquid lubricants - a computer simulation study
PublikacjaThis work is motivated by the improvement of anti-friction properties of lubricants by addition of CNTs proved experimentally in literature. In particular, a methodology is developed to compute the shear viscosity of liquid lubricants (Propylene Glycol) based on Molecular Dynamics simulation. Non-Equilibrium molecular dynamics (NEMD) approach is used with a reactive force field ReaxFF implemented in LAMMPS. The simulations are...
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Theoretical investigation of the structural insights of the interactions of γ-Fe2O3 nanoparticle with (EMIM TFSI) ionic liquid
PublikacjaOne of the possible applications of ionic liquids is to produce electricity from heat. The iron oxide nanoparticle is a potent electrical particle, which is expected to improve the heat’s efficiency to electricity conversion, however, it is prone to aggregation and sedimentation, which hamper its application. One of the methods to enhance the nanoparticle’s solubility and electrical properties is the use of a stabilizing component...
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The Relationship between the Structure and Properties of Amino Acid Ionic Liquids
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Study of the Resistance to Influence of Aggressive Liquids on Concrete with Lightweight Aggregate
PublikacjaThe corrosion of the structure of concrete caused by the aggressive external environment is one of the main problems that can reduce the durability of buildings. The paper analyzes the influence of the type of component on selected properties of lightweight concrete (LWC) exposed to aggressive liquids. When lightweight concrete containing porous aggregates is used, the influence of an aggressive environment may be of particular...
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Deep eutectic solvents vs ionic liquids: Similarities and differences
PublikacjaDeep eutectic solvents (DES) were introduced as an alternative to ionic liquids (IL) to overcome the drawbacks of IL solvents. However, some authors consider them to be a subclass of ILs. In contrast, other authors emphasize that these are by their nature independent, different groups of substances. Thus, the question arises: Which solvent group should DESs belong to? Maybe a new class should be added to the existing ones. The...
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Temperature-dependent structure-property modeling of viscosity for ionic liquids
PublikacjaIn this paper we present the methodology for assessing the ionic liquids' viscosity at six temperature points (25, 35, 45, 50, 60 and 70 [C]), which utilizes only the in silico approach. The main idea of such assessment is based on the "correction equation" describing the correlation between experimentally measured viscosity and theoretically derived density (calculated with use of molecular mechanics), given at 6 different temperature...
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Prospects of ionic liquids application in electronic and bioelectronic nose instruments
PublikacjaThis paper addresses the problem of application of ionic liquids to chemical sensors and biosensors being an integral part of the electronic and bioelectronic-type instruments. The design and principle of operation of the electronic and bioelectronic noses are compared. Both the benefits and shortcomings of the application of ionic liquids in these type of instruments are described. The prospects of the development and application...
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Recovery of ibuprofen from pharmaceutical wastes using ionic liquids
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Capillary electrophoretic separation of cationic constituents of imidazolium ionic liquids
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Exploiting isohexide scaffolds for the preparation of chiral ionic liquids tweezers
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Ionic liquids as an example of lubricating oils used in a field of tribology
PublikacjaPodczas prezentacji ustnej pokazano przykłady cieczy jonowych, ich możliwości w wykorzystaniu jako zastąpienie tradycyjnie używanych dziś smarów. Ponadto dokonano porównania kilku właściwości "tribologicznych" między cieczami jonowymi a obecnie wykorzystywanymi smarami
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Wetting of supports by ionic liquids used in gas separation processes
PublikacjaCiecze jonowe są stosowane w procesach separacji gazów jako selektywne rozpuszczalniki. Są szeroko stosowane w technologii immobilizowanych membran ciekłych, głównie w procesach oczyszczania strumieni gazowych. Praca ta charakteryzuje komercyjnie dostępne membrany porowate używane we wspomnianych procesach. Określenie właściwości nośników i fazy membranowej ma na celu wyznaczenie czynników mających wpływ na stabilności takich układów...
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Effect of oxygenation time on signal of a sensor based on ionic liquids
PublikacjaThe paper presents an oxygen sensor based on ionic liquids and solid electrodes. The following ionic liquids have been employed: [BMIM][BF4], [HMIM][Cl], [BMIM][N(CN2)]. Minimum time of the sensor exposure to analyte, after which the signal (current intensity) was stable, has been evaluated. An impact of volumetric flow rate of analyte on the sensor exposure time and signal has been determined. A product of permeability coefficient...
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Experimental study of the variations of the freezing points of ionic liquids in water
PublikacjaTemperatura zamarzania czystych soli alkiloimidazoliowych zawiera się w przedziale od - 70ºC do - 90ºC zależnie od długości podstawinika alkilowego oraz od rodzaju anionu. Celem niniejszej pracy jest znalezienie odpowiedniej metody pomiaru zmian temperatury zamarzania chlorku 1-metylo-3-oktyloimidazolu w wodzie. Wynik przeprowadzonych badań pozwolił na sporządzenie fragmentu diagramu fazowego dla wodnego roztworu chlorku...
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Chapter 23. Fate assessment of ionic liquids in porous media
PublikacjaW ostatnich latach obserwowany jest wzrost zainteresowania zastąpieniem tradycyjnych lubrykantów cieczami jonowymi z uwagi na ich szczególne właściwości fizykochemiczne zwłaszcza brak lotności -istotny z punktu bezpieczeństwa stosowania. Ciecze jonowe, choć nielotne, są związkami stosunkowo toksycznymi w stosunku do mikroorganizmów i bezkręgowców. Z tego względu ich zachowanie się w środowisku oraz parametry transportu powinny...
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How green are ionic liquids? – A multicriteria decision analysis approach
PublikacjaDue to various desirable physicochemical properties, ionic liquids (ILs) are still gaining in popularity. ILs have been recurrently considered green solvents. However, environmental, health and safety assessments of ILs have raised certain doubts about their benignness, and their greenness status is currently unclear. To clarify the situation on their greenness, we perform a comprehensive assessment of more than 300 commercially...
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Electrochemical investigations on corosivity of de-icing liquids for railway infrastructure
PublikacjaThe paper presents the results of electrochemical tests of the de-icing fluid for railway infrastructure. DC and AC electrochemical tests were performed to determine the corrosion rates of structural steel, cast iron and aluminium in the newly produced fluid. The results were compared with the corrosion rates of the same materials in the fluid without corrosion inhibitors. The obtained test results indicate a low corrosion risk...
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Effect of ionic liquids on surface and photocatalytic properties of selected semiconducttors
PublikacjaThe main aim of this doctoral dissertation was to explain the role of ionic liquids in shaping the morphology of selected semiconductors, thereby enhancing the photocatalytic activity. In order to achieve this goal, the following research steps were taken: (i) developing synthesis methods of selected semiconductors, with particular emphasis on the electrochemical oxidation method; (ii) understanding the influence of the selected...
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Experimental Study of the Resistance to Influence of Aggressive Liquids on Lightweight Concrete
PublikacjaIn light of the scientific research, the corrosion of concrete structures is one of the main problems that may reduce their durability due to the negative impact of the natural environment. The paper analyzes the influence of the type of component on the selected properties of lightweight concrete subjected to the influence of aggressive liquids. Four concrete mixes were prepared with a granular aggregate made of foamed glass (GEGA)...