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Simple method for preparation of Dialkyl (2,3-dihydro-1,3-thiazol-2-yl)-phosphonates
PublikacjaAbstract A simple synthesis of dialkyl (2,3-dihydro-1,3-thiazol-2-yl)-phosphonates from thiazoliumsalts and trialkyl phosphites is described. The series of dialkyl (2,3-dihydro-1,3-thiazol-2-yl)-phosphonates with various substituents in positions 3, 4, and 5 of the thiazole ring wereprepared. However, only phosphonates with an aryl on the nitrogen atom were stable enoughfor chromatographic purification, although all the new phosphonates...
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Ordered TiO2 nanotubes: the effect of preparation parameters on the photocatalytic activity in air purification process
PublikacjaVertically ordered TiO2 nanotube arrays were synthesized by anodic oxidation of titanium foil in glycerol, ethylene glycol and water-based electrolytes. The effect of electrolyte composition, anodization voltage, ultrasonic treatment and calcination time on the morphology of the resulting thin films, as well as on their photocatalytic activity in toluene removal, used as a model volatile organic compound, was investigated. Toluene,...
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Thermal Decomposition of Carbamoyl Meldrum’s Acids: A Starting Point for the Preparation of 1,3-Oxazine Derivatives
PublikacjaThe ability to undergo [4 + 2] versus [2 + 2] cycloaddition was under investigation for ketenes thermally generated from carbamoyl Meldrum’s acid. Usually, 1,3-oxazino-5-carbamoylo-4,6-diones are formed when carbamoyl Meldrum’s acid reacts with imine. However, in some cases, a reaction takes an unexpected course, leading to the formation of tetraponerines alkaloids derivatives or cyclic iminoethers.
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Preparation, morphology and properties of natural rubber composites filled with untreated short jute fibres
PublikacjaGreen composites were obtained by incorporation of short jute fibres in natural rubber matrix using a laboratory two-roll mill. The influence of untreated fibre content (1, 2.5, 5, 7.5 and 10 phr) on the mechanical properties, dynamic mechanical properties, swelling properties was examined. The behaviour of prepared green composites under cyclic compression was also investigated. Fibre dispersion in rubber matrix was studied by...
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Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography
PublikacjaIn 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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Softwood-lignin/natural rubber composites containing novel plasticizing agent: Preparation and characterization
PublikacjaComposite materials based on natural rubber were obtained by using glycerolysate (decomposition prod- uct of polyurethane) as a novel plasticizer. In order to determine the effect of various lignin content, four different filler amounts were used, namely, 5 phr (parts per 100 parts of natural rubber) of lignin (WLI5G), 10 phr (WLI10G), 20 phr (WLI20G), and 40 phr (WLI40G). The reference specimen without lignin (WLI0G) was also...
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Preparation, characterization and anti-colitis activity of curcumin-asafoetida complex encapsulated in turmeric nanofiber
PublikacjaUlcerative colitis (UC) is a main form of inflammatory bowel disease (IBD). Asafoetida (ASF) and turmeric have traditionally been used for the treatment of various inflammatory diseases, including UC, because ASF is rich in sulfur compounds and turmeric contains curcumin (CUR). Turmeric nanofiber (TNF), the modified cell wall component of turmeric is considered to play important role in the human diet, health and can be used as...
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Separation of saline oily wastewater by membrane distillation
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Ongoing Progress on Pervaporation Membranes for Ethanol Separation
PublikacjaEthanol, a versatile chemical extensively employed in several fields, including fuel production, food and beverage, pharmaceutical and healthcare industries, and chemical manufacturing, continues to witness expanding applications. Consequently, there is an ongoing need for cost-effective and environmentally friendly purification technologies for this organic compound in both diluted (ethanol-water–) and concentrated solutions (water-ethanol–)....
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The influence of frequency separation on imaging properties in DFEIT
PublikacjaW artykule przedstawiono wpływ wyboru składowych częstotliwościowych dla różnicowej tomografii impedancyjnej na wynik i własności obrazowania w dwuczęstotliwościowej różnicowej tomografii impedancyjnej.A Dual Frequency EIT is an extension of a traditional EIT that uses two sinusoidal signals for imaging. Appropriate selection of signals' frequency allows to achieve reasonable contrast of imaged structure. It has already been shown...
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Evaluation of the separation algorithm performance employing ANNs
PublikacjaCelem niniejszego rozdziału jest przedstawienie metodyki separacji dźwięków muzycznych bez informacji a priori o dźwiękach zawartych w muzycznym miksie. W pracy pokazano, że prawidłowo wytrenowana sztuczna sieć neuronowa (SNN)jest w stanie w sposób automatyczny poprawnie sklasyfikować dźwięki zawarte w zmiksowanym sygnale. Skuteczność klasyfikacji SNN jest porównywalna z oceną subiektywną ekspertów.
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Application of ionic liquids for gas separation processes
PublikacjaNowym 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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Preparation to ball on disk test Initial contact stress evaluation
Dane BadawczeEvaluation of initial contact stress in tests on wear of Al6061 alloy in ball on disk tribological testing. Research on the reinforcing effect of aluminium alloy injection reinforcement with TiN and WC powders in laser remelted surface layer.
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Theoretical Model of Acoustic Wave Propagation in Shallow Water
PublikacjaThe work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...
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Lamb wave propagation in a single lap adhesive joint
PublikacjaThe aim of the paper is the analysis of Lamb wave propagation in adhesive joints. The research was performed on a single lap adhesive joint of two steel plates. Two types of joints, namely an intact and with defect were considered. In experimental investigations the condition assessment of the joint was performed with the use of antisymmetric Lamb waves excited by a plate piezo actuators and measured by a laser vibrometer. Numeri-cal...
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Propagation of elestic waves in beams including damping effects.
PublikacjaW pracy przedstawiono wyniki analizy propagacji fali sprężystej w belce z tłumieniem wiskotycznym.
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Propagation in Rectangular Waveguides Periodically Loaded with Cylindrical Posts.
PublikacjaAnaliza rozchodzenie się fali elektromagnetycznej w falowodach prostokątnych z okresowo rozmieszczonymi cylindrycznymi obiektami. Wynikiem analizy są stałych rozprzestrzeniania rodzajów Floquet, które uzyskuje się z rozwiązania równania własnego. W artykule przeprowadzone zostało badanie teoretyczne i eksperymentalne struktur prawie-okresowych i ich macierzy rozproszenia. Pokazano również istnienie pasm przewodzących i zaporowych,...
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Numerical assessment of the fatigue crack propagation in ship structuraldetails.
PublikacjaPrzedstawiono podejście teoretyczne pozwalające na modelowanie rozwoju pęknięcia w konstrukcji kadłuba okrętu. Omówiono założenia i procedurę realizacyjną. Pokazano wyniki badań rzeczywistych modeli konstrukcji kadłuba-skrzyżowanie wiązań ramowych o jednakowej wysokości. Dokonano porównania i krytycznej analizy wyników uzyskanych na drodze teoretycznej z wynikami badań rzeczywistych.
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Flexural shera wave propagation in cracked composite beam.
PublikacjaW pracy przedstawiono model i wyniki analizy wpływu peknięcia na propagacje fali gietno-scinajacej w belce kompozytowej.
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A Finite Element Approach for Wave Propagation in Elastic Solids
PublikacjaThis book focuses on wave propagation phenomena in elastic solids modelled by the use of the finite element method. Although the latter is a well-established and popular numerical tool used by engineers and researchers all around the word the process of modelling of wave propagation can still be a challenge. The book introduces a reader to the problem by presenting a historical background and offering a broad perspective on the...
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Numerical analysis of elastic wave propagation in unbounded structures
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Wave propagation in a sensor/actuator diffusion bond model
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Lamb wave propagation in a single lap adhesive joint
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Bolted Joint Monitoring Using the Elastic Wave Propagation
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Calculation of the propagation loss in urban radio-access systems
PublikacjaZweryfikowano eksperymentalnie modele propagacyjne opracowane dla telefonii komórkowej w mieście, stosowane przy analizach projektowych systemów dostępowych. Przeprowadzono obszerne badania pomiarowe i zebrano prawie 19 tys. pomiarów. Na tej podstawie, stosując wielowymiarową analize regresji oraz zaproponowaną charakterystykę propagacyjną radiowych łączy dostępowych, opracowano nowy wielowariantowy model propagacyjny przeznaczony...
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Elastic wave propagation software in structural health monitoring
PublikacjaW pracy omówiono program do analizy propagacji fal spręzytsych w lementach konstrukcji z uszkodzeniami, oraz omówiono mozliwości jego wykorzystania do monitorowania stanu konstrukcji.
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Hyperbolic position location estimation in the multipath propagation environment
PublikacjaThe efficiency analysis a hyperbolic position location estimation in the multipath propagation environment in the wideband code division multiple access (WCDMA) interface was presented. Four, the most popular methods: Chan's, Foy's, Fang's and Friedlander's were considered. These algorithms enable the calculation of the geographical position of a mobile station (MS) using the time differences of arrival (TDOA) between several base...
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Propagation Path Loss Modeling in Container Terminal Environment
PublikacjaThis paper describes novel method of path loss modeling for radio communication channels in container port area. Multi-variate empirical model is presented, based on multidimensional regression analysis of real path loss measurements from container terminal environment. The measurement instruments used in propagation studies in port area are also described.
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Modeling of the acoustic waves propagation in non-homogeneous medium
PublikacjaRozważano zagadnienie propagacji fal w ośrodku niejednorodnym. Przedstawiono model matematyczny i przykładowe wyniki badań numerycznych. Model matematyczny zbudowano w oparciu o równanie KZK. Do rozwiązania zagadnienia zastosowano metodę różnic skończonych. Badano zmiany ciśnienia i zmiany widma odpowiednio w ośrodku jednorodnym i niejednorodnym.
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Polarized light pulses propagation and coupling in optical waveguides
PublikacjaGłównym celem tej pracy było zbudowanie modelu teoretycznego, na bazie równań Maxwella, który pozwoliłby na opis transmisji wielomodowej w falowodach dielektrycznych (światłowodach) z uwzględnieniem efektu nieliniowego typu Kerra. W pracy wyniki teoretyczne zostały porównane z wynikami doświadczalnymi. Do symulacji propagacji światła z uwzględnieniem efektu Kerra niezbędne było rozwiązanie sprzężonych nieliniowych równań Schrödingera...
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Propagation Path Loss Modelling in Container Terminal Environment
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Numerical analysis of elastic wave propagation in unbounded structures
PublikacjaThe main objective of this paper is to show the effectiveness and usefulness of the concept of an absorbing layer with increasing damping (ALID) in numerical investigations of elastic wave propagation in unbounded engineering structures. This has been achieved by the authors by a careful investigation of three different types of structures characterised by gradually increasing geometrical and mathematical description complexities....
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Path Loss Modelling in the Untypical Outdoor Propagation Environments
PublikacjaIn the paper three ways of path loss modelling in the untypical outdoor environments are presented. The exemplary untypical outdoor environment is analyzed. The investigated environment is characterized, and the measurement campaign are shortly described. The following models have been analyzed: the COST231 Walfisch-Ikegami model, the modified COST231Walfisch-Ikegami model tuned on the basis of empirical data, and the empirical...
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Features of Nonlinear Sound Propagation in Vibrationally Excited Gases
PublikacjaWeakly nonlinear sound propagation in a gas where molecular vibrational relaxation takes place is studied. New equations which govern the sound in media where the irreversible relaxation may take place are derived and discussed. Their form depends on the regime of excitation of oscillatory degrees of freedom, equilibrium (reversible) or non-equilibrium (irreversible), and on the comparative frequency of the sound in relation to...
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Experimental and numerical analysis of wave propagation in ground anchors
PublikacjaThe article focuses on wave propagation phenomenon in ground anchors. The main aim of the investigation is the non-destructive diagnostics and the assessment of the state of ground anchors, using the guided wave propagation method. Laboratory models of anchors with different lengths of the anchor body were tested and voltage signals of propagating waves were registered at several locations. For all tested specimens corresponding...
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Numerical FDM modelling of wave propagation in concrete structure
PublikacjaThe article presents application of finite difference method to damage detection and its size evaluation in concrete structure by elastic wave propagation method. The simulations of wave propagation in concrete structure were performed for six different damage scenarios. Damages were modelled as areas with changed material properties. Investigation focused on the influence of damage size on the energy of wave reflection. Presented...
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Numerical modeling of the nonlinear wave propagation in a bubble layer
PublikacjaRozważano zagadnienie propagacji fali wewnątrz warstwy z pęcherzykami. Omówiono model matematyczny, przedstawiono przykładowe wyniki badań teoretycznych. Analizowano zmiany ciśnienia wewnątrz warstwy, falę odbitą i bieżącą w ośrodku otaczającym, badano gęstość widmową mocy. Badania teoretyczne przeprowadzono dla różnych grubości warstwy, koncentracji pęcherzyków i wartości parametrów fali padającej.
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Induction machine behavioral modeling for prediction of EMI propagation.
PublikacjaThis paper presents the results of wideband behavioral modeling of an induction machine (IM). The proposed solution enables modeling the IM differential- and common-mode impedance for a frequency range from 1 kHz to 10 MHz. Methods of parameter extraction are derived from the measured IM impedances. The developed models of 1.5 kW and 7.5 kW induction machines are designed using the Saber Sketch scheme editor and simulated in the...
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Reservoir Influence on Pressure Wave Propagation in Steel Pipes
PublikacjaThe relation between the length of steel pipe and the pressure wave period in the system, reservoir-pipe-valve, is discussed. Experiments carried out for the short steel pipes showed that in such a system, the pressure wave celerity estimated using the measured wave cycles systematically increases with the increase of the pipe length. The observed differences can exceed even 90 m=s. As the pressure wave traveling in the pipe with...
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Selected Propagation Models Modification for Application in Container Terminal
PublikacjaIt is particularly important to look for any propagation model that could be useful for designing mobile radio systems in container terminal environment. The selected propagation models have been investigated. The applied research methodology has been described too. Results of the statistical adjustment in terms of signal loss determination in such environment have been analysed. The analysis have proved effectiveness of adjustment...
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Propagation of acoustic pulses in some fluids with yield stress
PublikacjaThis study is devoted to the derivation of approximate equations governing acoustic pulses in flows with yieldstress, including some time-dependent flows with a slow dependence on time of yield stress and apparent viscosity. Themodeling of yield stress and apparent viscosity in the vicinity of a zero deformation rate allows us to consider a thixotropicfluid as a Bingham plastic with coefficients that are dependent on time. The...
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High-performance method of carbon nanotubes modification by microwave plasma for thin composite films preparation
PublikacjaIn this work we present a simple and efficient method of nitrogen plasma modification of carbon nanotubes (CNTs). The process allows for treatment of the nanotubes in the form of powder with quite a high yield (65 mg of CNTs per hour). The modified carbon nanotubes contain approx. 3.8% of nitrogen, mostly in the pyridinic form. Plasma treated CNTs exhibit better dispersibility in water and higher electric capacitance than pristine...
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Implementing SP4CE Learning Rooms concept and AUTODESK online certification in the preparation of a new generation of engineers.
PublikacjaIn academia, educators do not always cope with rapidly changing technologies. Yet keeping up with new trends is essential to graduates’ success in a competitive job market. In the article, the author will answer the question of how Autodesk University Open Educational Resources and Certiport exams including GMetrix can enhance students’ academic progress and prepare them for future career. The concept of co-operation between Authorized...
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Preparation and Characterization of an Electrospun PLA-Cyclodextrins Composite for Simultaneous High-Efficiency PM and VOC Removal
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Microwave-Reactor-Based Preparation of Red Iron Oxide Pigment from Waste Iron Sulfate
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New Method for Photoactive Cement Preparation—Selected Mechanical Properties and Photocatalytic Activity of New Materials
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Esterification kinetics of glycerol with fatty acids in the presence of zinc carboxylates: Preparation of modified acylglycerol emulsifiers.
PublikacjaZbadano zależności kinetyczne estryfikacji glicerolu kwasami tłuszczowymi (C12:0 - C18:0), prowadzonych w obecności soli cynku tych kwasów tłuszczowych. Przeanalizowano wpływ temperatury, stężenia karboksylanu oraz budowy części hydrofobowej kwasu tłuszczowego i karboksylanu, na postęp reakcji estryfikacji. Wyznaczono wartości odpowiednich stałych szybkości reakcji, energii aktywacji oraz maksymalnej zawartości monoestru glicerolu,...
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Preparation of a Ceramic Matrix Composite Made of Hydroxyapatite Nanoparticles and Polylactic Acid by Consolidation of Composite Granules
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part II. Sample collection and preparation
PublikacjaThe paper reviews literature information on air sampling techniques commonly used for monitoring volatile organic compounds (VOCs) levels in atmospheric air. It describes containers for collecting samples of atmospheric air, such as vacuum canisters and bags made from synthetic materials. It discusses dynamic, passive and denudational techniques for sampling analytes from air combining isolation with preliminary enrichment, and...
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Sample preparation for gas chromatographic determination of halogenated volatile organic compounds in environmental and biological samples
PublikacjaPodstawowym elementem przygotowania próbek środowiskowych i biologicznych do analizy jest etap izolacji i/lub wzbogacania polegający na przeniesieniu analitów z matrycy pierwotnej charakteryzującej się złożonym i często zmiennym składem (próbka oryginalna) do matrycy wtórnej z równoczesnym usunięciem substancji przeszkadzających (izolacja)i zwiększeniem stężenia analitów do poziomu powyżej granicy oznaczalności stosowanego przyrządu...