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Search results for: PHASE-LAG PHENOMENON
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Quasi-discrete modelling of PMSM phase currents in drives with low switching-to-fundamental frequency ratio
PublicationThis study proposes a new quasi-discrete approach to modelling the permanent magnet synchronous motor (PMSM). The quasi-discrete modelling reflects the impact of continuous rotor movement, which takes place during a control cycle, on the shape of motor current waveforms. This provides much improvement in current modelling accuracy under inverter low switching-to-fundamental frequency operation. The proposed approach may be used...
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Adsorption of 1,2-Dichlorobenzene from the Aqueous Phase onto Activated Carbons and Modified Carbon Nanotubes
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Possibilities and benefits of a new method of modifying conventional building materials with phase-change materials (PCMs)
PublicationThe paper presents a current study devoted to the optimization of the amount of PCM present within traditional building materials, utilized in this case in hollow-brick walls. Authors focus on proposing an alternative to typical direct addition of PCM to existing building materials: introducing two- and three-component mixtures, based on a porous PCM carrier, which in this case was construction aggregate. Preliminary studies of...
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Dispersive Micro‐Solid Phase Extraction of Selected Metals in Water and Food Samples Followed by ICP‐OES Analysis: Method Development, Analysis of Real Samples and Greenness Evaluation
PublicationMultiwalled carbon nanotubes (MWCNTs) are well-known adsorbents because of their high surface area, layered and hollow architecture, hydrophobicity, and multiple and easily accessible adsorption sites. In this study, MWCNTs were used for dispersive micro-solid-phase extraction of various metal chelates in environmental and food samples. Different parameters such as concentration of the chelating reagent, the sorbent dosage, the...
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Optimization of a Fabric Phase Sorptive Extraction protocol for the isolation of six bisphenols from juice pouches to be analysed by high performance liquid chromatography coupled with diode array detector
PublicationFabric Phase Sorptive Extraction (FPSE) combined with high pressure liquid chromatography using to diode array detection (HPLC-DAD) was applied for the simultaneous determination of bisphenols (BPA, BPB, BPC, BPE, BPF, BPS) in juice pouches. The FPSE procedure was optimized with regards to the critical parameters that affect the performance of the method including the selection of the FPSE membrane type and size, adsorption time,...
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Investigation of use of hydrophilic/hydrophobic NADESs for selective extraction of As(III) and Sb(III) ions in vegetable samples: Air assisted liquid phase microextraction and chemometric optimization
PublicationIn this paper, a green, cost-effective sample preparation method based on air assisted liquid phase microextraction (AA-LPME) was developed for the simultaneous extraction of As(III) and Sb(III) ions from vegetable samples using hydrophilic/hydrophobic natural deep eutectic solvents (NADESs). Central composite design was used for the optimization of extraction factors including NADES volume, extraction cycle, pH, and curcumin concentration....
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Application of Headspace Solid-phase Microextraction with Poly(1-vinyl-3- Hexylimidazolium Chloride) Polymeric Ionic Liquid Coating using GC - MS to Determine Volatile Fatty Acids in Dairy Wastewater
PublicationVolatile fatty acids were determined in this study using headspace solid-phase microextraction (HS-SPME) with a poly(1-vinyl-3-hexylimidazolium chloride) polymeric ionic liquid coated fiber followed by gas chromatography - mass spectrometry. Experimental parameters such as extraction time and temperature, sample volume as well as desorption time and temperature were optimized. Detection limits of the method were in the range of...
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Sensorless algorithm for sustaining controllability of IPMSM drive in electric vehicle after resolver fault
PublicationThis paper presents a sensorless algorithm designated for the emergency control of an interior permanent magnet synchronous motor (IPMSM) drive in electric or hybrid vehicle. The algorithm is based on analysing the derivatives of motor phase currents measured over the duration of particular inverter states. The method is computationally simple and does not require additional hardware since the derivatives are measured indirectly....
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Gas‐Phase Removal of Indoor Volatile Organic Compounds and Airborne Microorganisms Over Mono‐ and Bimetal‐Modified (Pt, Cu, Ag) Titanium(IV) Oxide Nanocomposites
PublicationThe photocatalytic deactivation of volatile organic compounds and mold fungi using TiO2 modified with mono‐ and bimetallic (Pt, Cu, Ag) particles is reported in this study. The mono‐ and bimetal‐modified (Pt, Cu, Ag) titanium(IV) oxide photocatalysts were prepared by chemical reduction method and characterized using XRD, XPS, DR/UV‐Vis, BET and TEM analysis. The effect of incident light, type and content of mono‐ and bimetallic...
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Characterization of GM3 Gangliosides in Human Milk throughout Lactation: Insights from the Analysis with the Use of Reversed-Phase Liquid Chromatography Coupled to Quadrupole Time-Of-Flight Mass Spectrometry
PublicationGangliosides are complex lipids found in human milk that play important structural and biological functions. In this study, we utilized reversed-phase liquid chromatography coupled to quadrupole time-of-flight mass spectrometry to evaluate the molecular distribution of GM3 in human milk samples collected at distinct lactation stages, ranging from colostrum to advanced lactation samples. Throughout lactation, GM3 d40:1 emerged as...
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Application and optimization of headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography - flame-ionization detector (GC-FID) to determine products of the petroleum industry in aqueous samples
PublicationA simple and solvent-free analytical method has been optimized for the determination of hydrocarbons (C6 - C20) from products of the petroleum industry in aqueous samples. Extraction and analysis was carried out using headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled with flame-ionization detector (GC-FID). A ZB-5 capillary column (30 m × 0.25 mm inner diameter, 0.25 µm film thickness) was used for...
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A hierarchical porous composite magnetic sorbent of reduced graphene oxide embedded in polyvinyl alcohol cryogel for solvent‐assisted‐solid phase extraction of polycyclic aromatic hydrocarbons
PublicationA hierarchical porouscomposite magnetic sorbent was fabricated and applied tothe dispersive solvent-assisted solid-phase extraction of five polycyclic aromatichydrocarbons. A sorbent was first prepared by incorporating graphene oxide,calcium carbonate, and magnetite nanoparticles into a polyvinyl alcohol cryo-gel. The graphene oxide was converted to reduced graphene oxide using ascorbicacid and a hierarchical porous structure was...
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Direct Screening ofWater Samples for Benzene Hydrocarbon Compounds by Headspace Liquid-Phase Microextraction--Gas Chromatography
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Direct screening of ground water samples for fuel oxygenates by headspace liquid phase microextraction–gas chromatography
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Determination of volatile fatty acid ethyl esters in raw spiritsusing solid phase microextraction and gas chromatography
PublicationPrzedstawiono opracowanie i opymalizację metody analitycznej oznaczania estrów etylowych kwasów tłuszczowych w destylatach rolniczych różnej jakości lub wyprodukowanych z różnych surowców. W badaniach wykorzystywano technikę mikroekstrakcji do fazy stacjonarnej (HS-SPME) oraz kapilarnej chromatografii gazowej (CGC) z detektorem płomieniowo-jonizacyjnym (FID). Ekstrakcja związków lotnych prowadzona była według opracowanej procedury,...
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Solid phase synthesis of 4,5,8-trihydroxy-9,10-anthraquinone-1-yl-(tuftsin or retro-tuftsin) derivatives
PublicationPrzedstawiono syntezę na fazie stałej połączeń leuko-1,4,5,8-tetra-hydroksyantrachinonów z pochodnymi tuftsyny i retro-tuftsyny zawierającymi wiązanie izopeptydowe. Do syntezy wykorzystano standardową metodę Fmoc i DIC jako odczynnik aktywujący.
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Thermal analysis of macro-encapsulated phase change material coupled with domestic gas heater for building heating
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Two-phase flow phenomena assessment in minichannels for compact heat exchangers using image analysis methods
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Precise Evaluation of Gas–Liquid Two-Phase Flow Pattern in a Narrow Rectangular Channel with Stereology Method
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Gas chromatographic determination of volatile aliphatic and selected aromatic amines, without derivatization: solid phase microextraction
PublicationW pracy opisano wykorzystanie techniki chromatografii gazowej do oznaczania śladowych stężeń lotnych amin alifatycznych i wybranych amin aromatycznych w próbkach o różnym składzie matrycy. W tym przypadku aminy nie podlegają procesowi derywatyzacji przed etapem końcowym a na etapie pobierania próbek analitów jest wykorzystana technika mikroekstrakcji do fazy stacjonarnej (SPME).
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Oscillatory Mechanism of α-Fe(N) ↔ γ’-Fe4N Phase Transformations during Nanocrystalline Iron Nitriding
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Probability estimation of the city’s energy efficiency improvement as a result of using the phase change materials in heating networks
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Low-energy positron scattering from gas-phase tetrahydrofuran: A quantum treatment of the dynamics and a comparison with experiments
PublicationIn this paper we report new quantum calculations of the dynamics for low-energy positrons interacting with gaseous molecules of tetrahydrofuran. The new quantum scattering cross sections are differential and integral cross sections at collision energies between 1.0 and 25.0 eV and include a careful treatment of the additional effects on the scattering process brought about by the permanent dipole moment of the target molecule....
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Phase 3 randomised study of avatrombopag, a novel thrombopoietin receptor agonist for the treatment of chronic immune thrombocytopenia
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Analysis of mixing rules for the Stillinger-Weber potential: a case study of Ge-Si interactions in the liquid phase
PublicationCiekły stop Ge_{0.25}Si_{0.75} symulowano metodą dynamiki molekularnej, przy użyciu potencjału Stillingera-Webera. Badano wpływ parametryzacji członu potencjału odpowiedzialnego za oddziaływania trójciałowe w trójkach nieidentycznych atomów na strukturę symulowanego stopu. Wpływ ten okazał się być znaczący.Zmiany w parametrach rzędu kilku procent skutkowały istotnymi różnicami w parowych funkcjach rozkładu, kątowych funkcjach rozkładu...
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Headspace solid-phase microextraction and gas chromatography-olfactometry analysis of raw spirits of different organoleptic quality
PublicationCelem pracy było określenie, ktore związki wnoszą wkład w aromat destylatów rolniczych i wskazać te z nich które mogą powodować obniżenie ich właściwości organoleptycznych. W badaniach zastosowano ekstrakcję lotnych analitów z fazy nadpowierzchniowej techniką mikroekstrakcji do fazy nadpowierzchniowej w połączeniu z chromatografia gazową z detekcja olfaktometryczną . Znaleziono 40 zsubstancji, które mogą być markerami jakości organoleptycznej
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Detailed investigation of the phase transition inKxP4W8O32and experimental arguments for a charge density wave due to hidden nesting
PublicationDetailed structural and magnetotransport properties of monophosphate tungsten bronze Kx(PO2)4(WO3)8 single crystals are reported. Both galvanomagnetic and thermal properties are shown to be consistent with a charge density wave electronic transition due to hidden nesting of the quasi-1D portion of the Fermi surface. We also observe the enhancement of electronic anisotropy due to reconstruction of the Fermi surface at the Peierls...
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Chemically Bonded Silica Stationary Phases: Synthesis, Physicochemical Characterization, and Molecular Mechanism of Reversed-Phase HPLC Retention
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Examination of the influence of macro and microscopic parameters of limestone on the effectiveness of gas phase desulphurisation according to the method of wet limestone
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Determination of fluoride as fluorosilane derivative using reversed-phase HPLC with UV detection for determination of total organic fluorine
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Enhanced formability and forming efficiency for two-phase titanium alloys by Fast light Alloys Stamping Technology (FAST)
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On performance limits of switched-capacitor multi-phase charge pump circuits. Remarks on papers of Starzyk et al.
PublicationW pracy zweryfikowano hipotezę Starzyka nt. maksymalnego, osiągalnego wzmocnienia napięciowego w wielotaktowym konwerterze napięcia stałego typu C-przełączane (w tzw. pompie ładunkowej). W konwerterze zbudowanym z k kondensatorów maksymalne wzmocnienie określone jest przez odpowiednią potęgę liczby 2 tj. 2^(k-1) przy czym warunek podany przez Starzyka jest konieczny lecz nie jest dostateczny. Podano warunki konieczne i dostateczne...
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Investigating the Ischaemic Phase of Skin NADH Fluorescence Dynamics in Recently Diagnosed Primary Hypertension: A Time Series Analysis
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Silicon polypodands: powerful metal cation complexing agents and solid–liquid phase-transfer catalysts of new generation
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Tattooed man: Could menstrual cycle phase and contraceptive use change female preferences towards bad boys?
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A multi-pulse diode rectifier with a coupled three-phase reactor and additional small shunt active power filter
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Thermodynamic study of new antiepileptic compounds by combining chromatography on the phosphatidylcholine biomimetic stationary phase and differential scanning calorimetry
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Remission phase in children diagnosed with type 1 diabetes in years 2012 to 2013 in Silesia, Poland: An observational study
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Induction of G2/M phase arrest and apoptosis of human leukemia cells by potent antitumor triazoloacridinone C-1305
PublicationWykazaliśmy, że pochodna triazoloakrydonu C-1305 w stężeniach biologicznie istotnych indukuje blok cyklu komórkowego w fazie G2/M i apoptozę w komórkach białaczek ludzkich MOLT4 i HL60. Zjawisko apoptozy zostało określone na podstawie charakterystycznych zmian morfologicznych jak i biochemicznych tj. fragmentacji DNA, aktywacji kaspazy 3, cięcia PARP, spadku potencjału mitochondrialnego i ATP oraz eksternalizacji fosfatydyloseryny.
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Development of headspace solid-phase microextraction-gas chromatography method for the determination of solvent residues in edible oils and pharmaceuticals
PublicationW pracy przedstawiono wyniki opracowania procedury oznaczania pozostałości rozpuszczalników organicznych w olejach jadalnych z wykorzystaniem techniki HS-SPME na etapie izolacji i wzbogacania analitów. Przedstawiono proces optymalizacji etapu izolacji i rozdzielenia związków. Dla każdego z analitów wyznaczono parametry walidacyjne charakteryzujące procedurę tj. granice wykrywalności, granicę oznaczalności, liniowość, zakres pomiarowy,...
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Study of Phase Transformation Processes Occurring in the Nanocrystalline Iron/Ammonia/Hydrogen System by the Magnetic Permeability Measurement Method
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Solid phase extraction clean up of soil and sediment extracts for the determination of various types of pollutants in a single run.
PublicationOpisano nową procedurę oczyszczania ekstraktów rozpuszczalnikowych (uzyskanych w trakcie obróbki próbek gleby i osadów dennych) z wykorzystaniem techniki ekstrakcji do fazy stałej. Oryginalność podejścia polega na znalezieniu takiej kombinacji sorbentów, że uzyskuje się ekstrakt przygotowany do analizy chromatograficznej na zawartość różnych typów zanieczyszczeń (polichlorowane bifenyle, wielopierścieniowe węglowodory aromatyczne,...
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Experimental EMI study of a 3-phase 100kW 1200V Dual Active Bridge Converter using SiC MOSFETs
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Enhanced extraction of proteins using cholinium-based ionic liquids as phase-forming components of aqueous biphasic systems
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Physical aspect of application and usefulness of semi-Markovian processes for modelling the processes occurring in operational phase of technical objects.
PublicationW artykule zasygnalizowano przydatność teorii procesów semimarkowskich do tworzenia modeli procesów rzeczywistych, zachodzących w fazie eksploatacji różnych obiektów technicznych. Przydatność tej teorii została wykazana w wyniku przedstawienia: specyfiki procesów semimarkowskich oraz fizykalnych aspektów stosowania procesów semimarkowskich jako modeli procesów zachodzących w fazie eksploatacji wspomnianych obiektów. Specyfika została...
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Modeling and experimental investigation of the hydraulic jump in liquid film formed by an impinging two-phase air-water jet
PublicationPrzedstawiono model analityczny układu hydraulicznego powstałego na skutek uderzenia strugi dwufazowej wody i powietrza. Obliczenia porównano z badaniami eksperymentalnymi przeprowadzonymi na własnym stanowisku badawczym. Uzyskano zadowalającą zgodność.
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Tuning of the phase transition between site selective SCO and intermetallic ET in trimetallic magnetic cyanido-bridged clusters
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DEVELOPMENT OF HYDROGEL CAPSULES FOR USE IN DUAL-PHASE TOPICAL PREPARATIONS CONTAINING DIHYDROXYACETONE AND AMINO ACIDS – PRELIMINARY RESULTS
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Observation of the de Vries behavior in SmA* phase of a liquid crystal using polarised Raman scattering and infrared spectroscopy
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Macroscopic biaxiality and electric-field–induced rotation of the minor director in the nematic phase of a bent-core liquid crystal
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