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Wyniki wyszukiwania dla: PHASE-TRANSITIO
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The σ-phase superconductors Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9
PublikacjaWe show that the previously unreported ternary σ phases Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are both superconductors with Tc values of approximately 1.9 K. The superconducting transitions were characterized through temperature-dependent magnetic susceptibility, electrical resistance, and specific heat measurements. The Sommerfeld constants, γ, for Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are 89(1) mJ mol-f.u.−1K−2 and 86(1) mJ mol-f.u.−1K−2...
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Experimental investigation of a two-phase thermosiphon.
PublikacjaPrzedstawiono wyniki badań dwufazowego, termosyfonowego wymiennika ciepła. W szczególności uwzględniono wpływ podziałki rur oraz wartość ciśnienia w płaszczu na gęstość przenoszonego strumienia ciepła.
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Control of five-phase induction motor
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The phenylnitrene rearrangment in the inner phase of a hemicarcerand
PublikacjaOpisano przegrupowanie fenylonitrenu wewnątrz kompleksu hemikarceratowego.
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Automated Design of Linear Phase Filters
PublikacjaThis paper presents a fast technique for an automated design of microwave filters with linear phase. The proposed method exploits the cost function defined using the location of complex zeros and poles of the filter’s transfer and reflection function. The effectiveness of the proposed technique is presented with two illustrative examples.
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Principles and Developments of Solid-Phase Microextraction
PublikacjaSample preparation has been commonly considered a critical step of the analytical process. In this sense, remarkable efforts have been made to develop efficient sample preparation techniques which could overcome the limitations of conventional approaches. Since its inception in the early 1990’s, solid-phase microextraction (SPME) has become a widespread miniaturized sample preparation technique for extraction and preconcentration...
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Miniaturized solid-phase extraction techniques
PublikacjaMore than 80% of analysis time is spent on sample collection and sample preparation, so sample preparation is a critical part of the analytical process. Traditionally, liquid-liquid extraction was developed and employed to screen for general unknowns. However, solid-phase extraction (SPE) is becoming highly popular as an alternative, due to its simplicity and economy in terms of time and solvent. This review summarizes the current...
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Phase-difference positioning in asynchronous system
PublikacjaThis paper presents concept and implementation of digital positioning system based on phase difference measurements, designed as a navigational aid for marine applications. Main feature of proposed system is the ability to work in both synchronous mode, with one master station and set of slave stations synchronized with master, and in asynchronous mode with independent clocking of all stations.
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Liquid–phase microextraction: A review of reviews
PublikacjaSample preparation is an important step in chemical analysis. It is generally done to deal with problems associated with the nature of the matrix, low analyte concentrations in real samples or analyte features incompatible with the instrumentation. Classical methods of extraction consume large volumes of hazardous solvents and other reagents and are not in line with the recent emergence of green analytical chemistry. Liquid-phase...
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Superconductivity phase diagram of NaxCoO2*1.3H2O.
PublikacjaW pracy przedstawiono wpływ ilości sodu w nowo odkrytym nadprzewodniku NaxCoO2*1.3H2O na właściwości nadprzewodzące. Istnienie obszarów ''underdoped'' i''overdoped'' wskazuje na podobieństwo nowego systemu NaxCoO2 yH2O do wysoko-temperaturowych nadprzewodników tlenkowo - miedziowych.
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Open-Phase Fault Detection Method for Sensorless Five-Phase Induction Motor Drives with an Inverter Output Filter
PublikacjaThe paper presents the sensorless five-phase induction motor drive implementation with an inverter output filter with third harmonic injection. For the sensorless operation, the required observers are presented for the first and third harmonics with consideration of the inverter output filter. Moreover, the interaction of the observers and the control system is capable to handle a deactivation of one or two phases, which improves...
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Order-Disorder Transition in 2D Conserved Spin System with Cooperative Dynamics
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Calix[4]arene-Thioamides as Ionophores for Transition and Heavy Metal Cations.
PublikacjaPochodne kaliks[4]arenów odgrywają ważną rolę jako materiał aktywny w membranowych elektrodach jonoselektywnych. Obecnie duży nacisk kładzie się na kontrolę stężeń kationów metali ciężkich, takich jak Pb, Cd, Hg, Cu w wodach naturalnych. Naszym zadaniem było zaprojektować i zsyntezować ligandy, które wykazują zdolność do wiązania kationów metali ciężkich i przejściowych. Synteza, struktury krystaliczne, ekstrakcja i właściwości...
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Application of Coordination Compounds with Transition Metal Ions in the Chemical Industry—A Review
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Expression of Selected Epithelial-Mesenchymal Transition Transcription Factors in Endometrial Cancer
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Studies on the separation of some transition metals using trialkylimidazole as selective extractant
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Do Judges’ Delegations Affect Judicial Performance? A Transition Economy Evidence
PublikacjaThe aim of this study is to discern whether, by delegating judges from the court to the Ministry of Justice, the Minister of Justice influences the results of courts in terms of adjudication. The study used a unique set of data for the Polish judicial system over a period of five years. The research results indicate that there are three reasons for delegating judges. Firstly, the delegation system serves to fill staff shortages...
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A mobile loop order–disorder transition modulates the speed of chaperonin cycling
PublikacjaMolecular machines order and disorder polypeptides as they form and dissolve large intermolecular interfaces, but the biological significance of coupled ordering and binding has been established in few, if any, macromolecular systems. The ordering and binding of GroES co-chaperonin mobile loops accompany an ATP-dependent conformational change in the GroEL chaperonin that promotes client protein folding. Following ATP hydrolysis,...
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First-order magnetic transition in single-crystallineCaFe2As2detected byA75snuclear magnetic resonance
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Superconducting transition in granular Bi-Sr-Ca-Cu-O superconductors
PublikacjaW układzie(Bi,Pb)-Sr-Ca-Cu-O poprzez krystalizację w fazie stałej można wytworzyć materiały o bardzo różnych właściwościach elektrycznych i nadprzewodzących. W zależności od warunków krystalizacji, można wytworzyć nadprzewodnik o temperaturze krytycznej między 8 a 105 st. K lub materiał nie przechodzący do stanu nadprzewodzącego. Przejście do stanu nadprzewodzacego w materiałach granulastych ma charakter dwustopniowy. Zbadano wpływ...
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Calix[4]arene-Thioamides as Ionophores for Transition and Heavy Metal cations
PublikacjaCalix[4]arene derivatives play an important role as sensing materials in Ion Selective Electrodes(ISEs). Nowadays a high impact is put to control in natural waters the level of toxic heavy metals, like Pb ,Cd, Hg or Cu which may cause the great risk to human health. Our goal was to design and to synthesize ligands possessing ability to bind transition and heavy metal cations. The synthesis, crystal structures,extractive and ionophoric...
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Global energy transition: From the main determinants to economic challenges regions
PublikacjaDynamic global energy transition has been accelerating for the last decade. Interestingly, the energy transition is multidimensional and concerns both the dimensions of technique/ technology and the economic, social, institu-tional, and legal spheres (Shuguang et al., 2022; Tzeremes et al., 2022; Ram-zan et al., 2022; Tzeremes et al., 2022). The literature also points to the signif-icant impact of the digitization of the global...
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S-Shaped Suppression of the Superconducting Transition Temperature in Cu-Intercalated NbSe2
Publikacja2H-NbSe2 is the prototype and most frequently studied of the well-known transition metal dichalcogenide (TMDC) superconductors. As 2H-NbSe2 is widely acknowledged as a conventional superconductor, its transition temperature to the superconducting state (Tc) is 7.3 K, a Tc that is substantially higher than those seen for the majority of TMDCs, where Tc values between 2 and 4 K are the norm. Here we report the intercalation of Cu...
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Introduction to smart solutions for wastewater: Road-mapping the transition to circular economy
PublikacjaToday there is an urgent need to move from a linear to a circular economy approach with special focus to water and environment. Despite the paramount importance, this transition is hampered by barriers which concern not only technological but embrace also organizational, regulatory, social, and economic aspects. In order to overcome such barriers, innovative water-smart solutions are needed and a robust roadmap for the transition...
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Phase I and phase II metabolism simulation of antitumor-active 2-hydroxyacridinone with electrochemistry coupled on-line with mass spectrometry.
PublikacjaHere, we report the metabolic profile and the results of associated metabolic studies of 2-hydroxyacridinone (2-OH-AC), the reference compound for antitumor-active imidazo- and triazoloacridinones. Electrochemistry coupled with mass spectrometry was applied to simulate the general oxidative metabolism of 2-OH-AC for the first time. The reactivity of 2-OH-AC products to biomolecules was also examined. The usefulness of the electrochemistry...
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Thermodynamic properties and phase stability of wadsleyite II
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Integrated Three-Level Dual-Phase Inverter
PublikacjaIn view of reducing the number of inverter legs that provide dual-phase, three-level output voltages (as may be needed in an uninterruptible power supply), and that also provide a wide range of output frequencies (as needed in an advanced motor drive system with wide speed ranges), a three-level, dual-phase inverter topology is presented in this paper. Its three-level attribute was based on the F-type inverter topological concept,...
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MgPdSb─An Electron-Deficient Half-Heusler Phase
PublikacjaThe half-Heusler family consists of many semiconducting intermetallic compounds, virtually all of them having a valence electron count (VEC) of 18. We have studied an electron-deficient (VEC = 17) phase MgPdSb and its Pd-stuffed variant MgPd1.25Sb. The cubic F4̅3m crystal structure was confirmed by the Rietveld refinement of powder X-ray diffraction (XRD) data. The lattice parameter is a = 6.284 and 6.335 Å for MgPdSb and MgPd1.25Sb,...
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Roadmap on dynamics of molecules and clusters in the gas phase
PublikacjaThis roadmap article highlights recent advances, challenges and future prospects in studies of the dynamics of molecules and clusters in the gas phase. It comprises nineteen contributions by scientists with leading expertise in complementary experimental and theoretical techniques to probe the dynamics on timescales spanning twenty orders of magnitudes, from attoseconds to minutes and beyond, and for systems ranging in complexity...
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Transesterification of postfrying oils and utilization of the glycerol phase
PublikacjaPrzedstawiono metodę wytwarzania biodiesla z oleju posmażalniczego oraz zaproponowano sposób zagospodarowania gliceryny, powstającej jako produkt uboczny tego procesu. Wykazano, że odpadowy olej jadalny może stanowić substrat reakcji transestryfikacji prowadzącej do otrzymania EMKT. Przeprowadzono proces transestryfikacji zasadowej I i II- stopniowej oraz estryfikację kwaśną. Właściwości fizykochemiczne otrzymanego paliwa porównano...
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Phase investigations of copper based CuZn38Al2MnFe alloy
PublikacjaW pracy przedstawiono analizę fazową mosiądzu CuZn38Al2MnFe. Wykazano, że obecność fazy Fe4Mn77Si19 powoduje kruchość stopu w teście zginania próbek.
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THE PHASE SHIFTERS INFLUENCE ON THE POWER SYSTEM STABILITY
PublikacjaThe paper presents the effect of phase shifters as FACTS devices on the possibility of improving the angle stability. Presented results obtained by the dynamic simulation performed on the mathematical model of the three machine system cooperating with the 400 kV network. The generative blocks models include turbine models with their controllers and models of synchronous generators with their excitation systems and voltage regulation....
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New Polymeric Materials for Solid Phase Extraction
PublikacjaSolid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas–solid phase and liquid–solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward...
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Superconductivity in the Nb-Ru-Ge σ phase
PublikacjaWe show that the previously unreported ternary σ-phase material Nb20.4Ru5.7Ge3.9 (Nb0.68Ru0.19Ge0.13) is a superconductor with a critical temperature of 2.2 K. Temperature-dependent magnetic susceptibility, resistance, and specific-heat measurements were used to characterize the superconducting transition. The Sommerfeld constant γ for Nb20.4Ru5.7Ge3.9 is 91 mJ mol f.u. −1K−2 (∼3 mJ mol atom−1 K−2) and the specific-heat anomaly at...
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Digital phase-location system for marine applications
PublikacjaThis paper presents concept and implementation of digital phase-location system, designed as a navigational aid for marine applications. Main feature of proposed system is the ability to work in both synchronous mode, with one master station and set of slave stations synchronized with master, and in asynchronous mode with independent clocking of all stations.
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Influence of the air phase on water flow in dikes
PublikacjaNumerical models are often used to describe flow and deformation processes occurring in dikes during flood events. Modeling of such phenomena is a challenging task, due to the complexity of the system, consisting of three material phases: soil skeleton, pore water and pore air. Additional difficulties are transient loading caused by variable in time water levels, heterogeneity of the soil or air...
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Stabilization of the pyrochlore phase of Mn2Sb2O7 by double substitution
PublikacjaPolycrystalline samples of (Ce4+Mn2+3)(Ga3+Sb5+3)O14 were synthesized by a high-temperature solid-state reaction. In contrast with the parent Mn2Sb2O7 compound that adopts a rhombohedral or monoclinic structure at T > 600 °C, the pyrochlore structure of CeMn3GaSb3O14 is retained up to at least T = 1070°C. High-resolution synchrotron x-ray diffraction measurements show no sign of a superstructure or distortion from cubic symmetry...
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Identification of multisite behavior in a broadly emitting transition-metal system using pressure
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Restructuring of the Coal Mining Industry and the Challenges of Energy Transition in Poland (1990–2020)
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Assessment of the effect of vegetation on the transition of the flood wave using hydraulic 2D models
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Surface area investigation of materials with transition layers of continuously changing electron density
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Apparent molar volumes of divalent transition metal bromides in dimethyl sulfoxide solutions
PublikacjaWyznaczono pozorne i cząstkowe molowe objętości bromków dwuwartościowych metali przejściowych szeregu Mn(II)-Zn(II)w roztworach w dimetylosulfotlenku. Przedyskutowano korelacje między objętościami molowymi a stanami koordynacyjnymi i sposobem jonizacji soli.
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The time of the first transition of the semi-Markov process in the evaluation of diesel engine operation
PublikacjaW referacie przedstawiono rozwinięcie prezentowanej w literaturze metody ilościowej oceny działania na przykładzie okrętowego silnika głównego z zapłonem samoczynnym. Według tej interpretacji, działanie silnika może zostać przedstawione jako wielkość fizyczna. W tym aspekcie, na przykładzie okrętowego silnika napędu głównego dokonano oceny przydatności tej wielkości do opisu własności niezawodnościowych silnika. Precyzyjne określenie...
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On the fast BSS transition algorithms in the IEEE 802.11r local area wireless networks
PublikacjaHandover performance is critical to support multimedia services that are becoming increasingly available over the wireless devices. The high transition delay can be unaccepted for such services or can be a source of disruption on the session. On the other side, IEEE 802.11 standard is being extended with new functionalities. Security and QoS features, included in recent IEEE 802.11-2007 standard, add management frames that are...
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Transition-Metal-Promoted Oxidative Cyclization To Give 1,2,4-Trisubstituted Carbazole Scaffolds
PublikacjaHerein, we describe the synthesis of a 1,2,4-trisubstituted carbazole core from 5-(1H-indol-3-yl)-3-oxopentanoic acid esters or amides. For oxidative cyclization, we tested two different approaches. First, we used manganese triacetate as a conventional moderate oxidizer to ensure the radical course of the reaction. Second, we examined the use of a more complex oxidizing agent I2/Me(OTf)3. In both cases, formation of a fused-ring...
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Integrating Art into Places in Transition - Rose Kennedy Greenway in Boston as a Case Study
PublikacjaAmong the many projects realized in public spaces, some are truly unique – and these are the ones that build the identity of a place. The aim of this paper is to examine how integrating art and cultural strategies into public space can enhance and reinforce the sense of a place. Particular attention is devoted to urban spaces that we call “places in transition”, where public art improves the city’s imaginative capacity, enlivens...
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Closing the gap – the opportunity for sustainability and smart transition in the Central and East Europe countries
PublikacjaFor almost half a century the countries of CEE were part of- or were remaining under the influence of- the Soviet Union what caused gaping difference in the starting line towards sustainability. Here the prefabricated concrete blocks of flats were being built at the scale unseen in the western countries. Those buildings, approximately a quarter of the residential market, are in a structurally sound condition to last another five...
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Gel glass transition in silica and nitrided silica aerogels experiment and computer modelling.
PublikacjaPrzedstawiono dane eksperymentalne i symulacje komputerowe metodą dynamiki molekularnej procesu densyfikacji do szkła aerożeli krzemianowych i azotowanych aerożeli krzemianowych.
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A constitutive law for concrete with smooth transition from continuous into discontinuous cracks’ description
PublikacjaPaper presents a constitutive model for concrete that combines a continuous and discontinuous crack’s description to simulate the concrete under tensile dominated loads. In a continuum regime, two different constitutive laws were used. First, a plasticity model with the Rankine failure criterion and an associated flow rule was used. Second, a constitutive law based on isotropic damage mechanics was formulated. Both model alternatives...
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Inferring perfect phylogenies with restrictions on character state transitions
PublikacjaZnana z klasycznej literatury metoda rekonstrukcji drzewa filogenetycznego zbioru gatunków na podstawie ich cech analizowanych w modelu doskonałej filogenezy często okazuje się niewystarczająca ze względu na założenia tego modelu, zmuszające do pominięcia znanych biologom informacji. W pracy definiujemy rozszerzenie umożliwiając wprowadzenie dla każdej cechy grafu skierowanego dopuszczalnych przejść ewolucyjnych pomiędzy jej stanami....