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Stan czystości jezior na terenie województwa Pomorskiego = Water quality of the lakes in the Pomerania Province
PublicationW ramach części doświadczalnej pracy przeprowadzono analizę jakości wód z wybranych jezior. Wykonano analizy nastepujących parametrów: pH, NO3-, NO2-, F-, NH4+, Cl-, HS-, SO42-, Fecal, Mn2+, PO43-, SiO2, Al3+. Dla wybranych próbek zmierzono również parametr toksyczności. W przypadku dwóch próbek jego wysokość wskazywała na to, że badana woda zawierała substancje toksyczne. Na podstawie uzyskanych wyników badane próbki wody pochodzące...
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Propulsion and Maneuvering Systems’ Characteristics of the U.S. Flagged Great Lakes Self-Unloading Bulk Carriers
PublicationPaper contains an overview of the propulsion and maneuvering systems’ characteristics of United States flagged Great Lakes self - unloading bulk carriers. A contrast between the importance of the transport task carried by those vessels to their low number and considerable age suggests the need to review and understand their complexity as well as complexity of their operations in order to provide suitable energy- and operational...
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Elastic waves in the railroad track substructures and its surroundings analyzed with non-classical operational methods
PublicationWe analyze the propagation of the waves generated by the rolling stock and the interaction of those waves on the medium and its surroundings. We use non-classical operational methods for monitoring construction of the railway infrastructure and for noise damping.
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The Specific Nature of Chemical Composition of Water from Volcanic Lakes Based on Bali Case Study
PublicationThe research area was localized in the Indonesian Archipelago, at the latitude of eight and nine degrees S on the one of the Lesser Sunda group island provinces, Bali (563,3 km2). Two massive calderas (Mount Batur 1717 m above sea level.; Mount Sangiyang 2093 m above sea level) are one of the most prominent landforms in the chain of volcanic mountain ranges of the Bali Island. Lake Batur (17,18 km2) and Batur Spring (which are...
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REVERSE MODELLING OF MICROSEISMIC WAVES PROPAGATION FOR THE INTERPRETATION OF THE DATA FROM HYDRAULIC FRACTURING MONITORING IN POLAND
PublicationA hydraulic fracturing job was performed to stimulate gas flow from a horizontal wellbore located in Poland. The whole operation was overseen by means of microseismic monitoring. For this purpose, an array of 12000 geophones was deployed on ground in form of patches distributed unevenly in a region of 4km from the wellbore. The array was constantly recording seismic signals during whole fracturing processed. Such recorded signals...
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Theoretical methods in thermodynamics of condensed phases
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Possible quadrupole-order-driven commensurate-incommensurate phase transition in B20 CoGe
PublicationThe B20-type cobalt germanide CoGe was investigated by measuring the specific heat, resistivity, and 59Co nuclear magnetic resonance (NMR).We observed a phase transition at TQ = 13.7 K, evidenced by a very narrow peak of the specific heat and sharp changes of the nuclear spin-spin (T −1 2 ) and spin-lattice (T −1 1 ) relaxation rates. The fact that the entropy release is extremely small and the Knight shift is almost independent...
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Multimodal Genetic Algorithm with Phase Analysis to Solve Complex Equations of Electromagnetic Analysis
PublicationIn this contribution, a new genetic-algorithm-based method of finding roots and poles of a complex function of a complex variable is presented. The algorithm employs the phase analysis of the function to explore the complex plane with the use of the genetic algorithm. Hence, the candidate regions of root and pole occurrences are selected and verified with the use of discrete Cauchy's argument principle. The algorithm is evaluated...
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Improvements to the two-phase sandwich method for calculating the melting points of pure metals
PublicationThe thermophysical properties of metal alloys are often investigated via molecular dynamics (MD) simulations.An exact and reliable estimation of the thermophysical parameters from the MD data requires a properly and carefullyelaborated methodology. In this paper, an improved two-phase sandwich method for the determination of the metal meltingtemperature is proposed, based on the solid-liquid equilibrium theory. The new method was...
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Study of Phase and Chemical Composition of Bi1-xNdxFeO3 Powders Derived by Pressureless Sintering
PublicationIn the present paper studies on Bi1xNdxFeO3 for x =0.1-0.4 are reported. The mixed oxide method followed with pressureless sintering was employed for ceramics fabrication. Thermal behavior of stoichiometric mixtures of simple oxide powders, viz. Bi2O3, Nd2O3 and Fe2O3 was studied by simultaneous thermal analysis. It was found that with an increase in neodymium content the weight loss increased from 0.75% to 3.16% for x =0.1 and...
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Fault-tolerant performance of the novel five-phase doubly-fed induction generator
PublicationThe article presents the concept of a new design of a multi-phase doubly-fed induction generator (DFIG). The innovative design approach uses a five-phase power supply from the rotor side of the generator with a three-phase classic stator power supply. Modern three-phase doubly-fed induction generators are the dominant choice for Wind Energy Conversion Systems (WECS). Solutions of this type are sensitive to the loss of at least...
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Active Control of Highly Autocorrelated Machinery Noise in Multivariate Nonminimum Phase Systems
PublicationIn this paper, a novel multivariate active noise control scheme, designed to attenuate disturbances with high autocorrelation characteristics and preserve background signals, is proposed. The algorithm belongs to the class of feedback controllers and, unlike the popular feedforward FX-LMS approach, does not require availability of a reference signal. The proposed approach draws its inspiration from the iterative learning control...
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Measurements of Two-phase Flows in Pipelines Using Radioisotopes and Statistical Signal Processing
PublicationThis paper presents an application of radiotracers and gamma absorption method in two-phase flow measurements in pipelines. Two different methods were implemented to analysis of acquired signals. Investigated methods are based on the cross-correlation function and the phase of the cross-spectral density distribution. The examples presented in the article illustrate the application of the radioisotopes to evaluation of liquid-gas...
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How Does International Competitiveness Affect Economic Development? A Two-Phase Hypothesis
PublicationThis paper analyses the impact of international competitiveness on economic development, based on the World Economic Forum Global Competitiveness Index (GCI) and GDP/capita of 125 countries during the period 2007-2010. The results reveal two phases of the evolution of competitiveness. When GCI < 4.5 (on 1-7 scale), any improvement of a country’s competitiveness affects current development more than future development. When...
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Application of surface active amino acid ionic liquids as phase-transfer catalyst
PublicationFive structurally related morpholinium derived ionic liquids containing N-acetyl-glycinate anion were synthesized and their thermal stability, surface properties and activity as phase transfer catalysts investigated. The thermal properties were studied by differential scanning calorimetry, while the adsorption at the air/water interface and micellization behavior was analyzed by surface tension measurements, conductometry and isothermal...
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“Shadow” vs. “Phase 3D” method within endoscopic examinations of marine engines
PublicationA visual investigation of surfaces creating internal, working spaces of marine combustion engines by means of specialized view-finders so called endoscopes is at present almost a basic method of technical diag-nostics. The surface structure of constructional material is visible during investigations like through the magnifying glass (usually with a precisely determined magnification), which makes possible a detection, recognition...
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The Possibility of Phase Change Materials (PCM) Usage to Increase Efficiency of the Photovoltaic Modules
PublicationSolar energy is widely available, free and inexhaustible. Furthermore this source of energy is the most friendly to the environment. For direct conversion of solar energy into useful forms like of electricity and thermal energy, respectively photovoltaic cells and solar collectors are being used. Forecast indicate that the first one solution will soon have a significant part in meeting the global energy demand. Therefore it is...
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Numerical Simulations of Seepage in Dikes Using unsaturated and Two-Phase Flow Models
PublicationModeling of water flow in variably saturated porous media, including flood dikes, is often based on the Richards equation, which neglects the flow of pore air, assuming that it remains at constant atmospheric pressure. However, there is also evidence that the air flow can be important, especially when the connectivity between the pore air and atmospheric air is lost. In such cases a full two-phase air-water flow model should be...
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Phase change thermal energy storage – the experience of the materials preparation for the specific applications.
PublicationThermal energy storage and temperature stabilization is very important in many engineering applications. There are three kinds of thermal energy storage: sensible heat, latent heat and reversible chemical reaction heat. Phase change materials (PCM) absorb, store and release large amounts of energy in the form of latent heat, at constant temperature, called the transition temperature. Many innovative applications could be found...
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Change of the Phase Composition and Strength of Al2O3–ZrO2-Ceramic After Hydrothermal Aging
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The triple-sorbents solid-phase extraction for pharmaceuticals and estrogens determination in wastewater samples
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Luminescent and Scintillation Properties of CeAlO3 Crystals and Phase-Separated CeAlO3/CeAl11O18 Metamaterials
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P3HT:PCBM blend films phase diagram on the base of variable-temperature spectroscopic ellipsometry
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How Do Intermolecular Interactions Evolve at the Nematic to Twist–Bent Phase Transition?
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Phase diagram of P3HT:PC70BM thin films based on variable-temperature spectroscopic ellipsometry
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Anomalous Thermal Behavior of Salicylsalicylic Acid and Evidence for a Monotropic Transition to a Nematic Phase
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The existence and gas phase acidity of the HAlnF3n+1 superacids (n=1–4)
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A new method for preparation of rutile phase titania photoactive under visible light
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Silicon polypodands: a new class of efficient solid–liquid phase-transfer catalysts
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Application of a new class B-podands in solid–liquid phase transfer catalysis
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A new type of B-podand catalysts for solid–liquid phase transfer reactions
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Headspace liquid phase microextraction for quantitation of hexanal in potato crisps by gas chromatography
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Solid-phase microextraction and ion chromatographic analysis of anions based on polypyrrole electrode
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In-Tube Molecularly Imprinted Polymer Solid-Phase Microextraction for the Selective Determination of Propranolol
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Kinetics of Biotic and Abiotic CO Production during the Initial Phase of Biowaste Composting
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Volatile organic compound separation from gas phase using ionic liquids
PublicationZanieczyszczenie powietrza lotnymi związkami organicznymi staje się światowym problemem ochrony środowiska w związku z ich toksycznymi właściwościami. W związku z tym poszukuje się nowych, efektywnych technologii oczyszczania strumieni gazowych. Powszechnie stosowaną metodą jest utlenianie termiczne. Wiąże się ono jednak z Wysokiem zużyciem energii i efektami ubocznymi w postaci emisji dwutlenku węgla i tlenków azotu. Alternatywą...
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Analysis of IMS/NGN call processing performance using phase-type distributions
PublicationThis work is a continuation of our research on the traffic model dedicated for design and analysis of the Next Generation Network (NGN), which is standardized for distribution of current and future multimedia services based on the IP Multimedia Subsystem (IMS). Our analytical and simulation models allow evaluation of mean Call Set-up Delay E(CSD) as well as mean Call Disengagement Delay E(CDD) in a single domain of IMS/NGN. Ensuring...
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Analysing the potential for application of the phase shift method in endoscopic examination of marine engines
PublicationThe article presents theoretical principles of image processing in digital endoscopy which makes use of a miniaturised spectral scanner “PhaseProbe” designed by General Inspection Technologies LP, the producer of the measuring videoendoscope Everest XLG3. The technology of optoelectronic 3D mapping of the examined surface, which consists in measuring the phase shift between the emitted and reflected light waves, is briefly described....
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Effects of subfilter velocity modelling on dispersed phase in LES of heated channel flow
PublicationA non-isothermal turbulent flow with the dispersed phase is modelled using the Large Eddy Simulation (LES) approach for fluid, one-way coupled with the equations of point-particle evolution. The channel is heated at both walls and isoflux boundary conditions are applied for fluid. Particle velocity and thermal statistics are computed. Of particular interest are the r.m.s. profiles and the probability density function of particle...
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Solid phase synthesis and biological activity of linear tuftsin and retro-tuftsin derivatives
PublicationPrzedstawiono syntezę na fazie stałej nowych pochodnych tuftsyny i retro-tuftsyny i ich mikrobiologiczne właściwości. Otrzymane pochodne zawierały wiązanie izopeptydowe między epsilon-aminową grupą lizyny a takimi aminokwasami jak: Ala, beta-Ala, Val, Ile, Gly.
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Solid phase synthesis of conjugates of tuftsin analogues with 1-nitro-acridine derivatives
PublicationZsyntetyzowano na fazie stałej koniugaty 1-nitro-akrydyny z pochodnymi tuftsyny modyfikowanymi na grupie epsilon-aminowej lizyny prostymi aminokwasami, np. alaniną, valiną, beta-alaniną. Końcowe produkty były charakteryzowane za pomocą MS, NMR, analizy elementarnej i przekazane do badań ich aktywności przeciwnowotworowej.
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Numerical calculation of three-phase transformer's residual flux in ATP and PSpice programs.
PublicationW artykule przedstawiono analizę przebiegów prądu i strumienia magnetycznego podczas wyłączania transformatora energetycznego, wykonaną w celu określenia strumieni szczątkowych. Wykorzystano do tego celu modele obwodowe zbudowane w oparciu o programy symulacyjne ATP (Alternative Transients Program) i PSpice. Wyniki obliczeń okazały się bardzo zbliżone dla obu modeli. Przy ich wykorzystaniu obliczono strumienie szczątkowe w kolumnach...
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Balance of pesticides mass in gas, liquid and solid phase after their chemical degradation.
PublicationOpisano metodę usuwania pestycydów z wody przy zastosowaniu fotodegradacji (UV) i katalizatora (TiO2). Efektywność procesu usuwania pestycydów była kontrolowana przy zastosowaniu chromatografu gazowego z detektorem wychwytu elektronów. Oznaczano zawartość pestycydów w wodzie, a także zaadsorbowanych na powierzchni stałej, oraz w fazie gazowej. Największa zawartość pestycydów znajdowała się na fazie stałej, następnie w cieczy i...
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Preliminary investigations on biological treatment of aqueous phase separated from cutting fluids
PublicationZaprezentowano wyniki fizykochemicznego podczyszczania przepracowanych cieczy obróbkowych pochodzących z różnych źródeł. Emulsje przepracowanych cieczy obróbkowych zostały rozdzielone na fazę organiczną i wodną z wykorzystaniem różnych koagulantów. Wydzielona faza wodna została następnie poddana biologicznemu oczyszczaniu z wykorzystaniem osadu czynnego. W wyniku oczyszczania ścieków uzyskano 59-88% obniżenie wartości ChZT.
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Static headspace sampling and solid-phase microextraction for assessment of edible oils stability
PublicationStatyczna analiza fazy nadpowierzchniowej i mikroekstrakcja do fazy stacjonarnej z fazy nadpowierzchniowej zostały zastosowane do oznaczenia niskocząsteczkowych aldehydów - markerów procesu utleniania olejów roślinnych. Zoptymalizowano parametry izolacji i ekstrakcji analitów dla obu technik. Wyznaczono granice oznaczalności i wykrywalności oraz powtarzalność dla badanych związków. Obie metody zastosowano w analizie próbek olejów...
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Generalized adaptive notch filters with frequency debiasing for tracking of polynomial phase systems
PublicationGeneralized adaptive notch filters are used for identification/tracking of quasi-periodically varying dynamic systems and can be considered an extension, to the system case, of classical adaptive notch filters. For general patterns of frequency variation the generalized adaptive notch filtering algorithms yield biased frequency estimates. We show that when system frequencies change slowly in a smooth way, the estimation bias can...
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Matrix solid-phase dispersion with sand in chromatographic analysis of essential oils in herbs
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Effect of structure modification with potassium on grains layer creation process and phase transitions
PublicationZbadano szkła germanianowo-ołowiowe i krzemianowo bizutowe. Wartwy metalicznych granul wytwarzano w nich poprzez redukcję powierzchni w atmosferze wodoru. Praca dotyczy wpływu potasu na tworzenie się warstwy granul oraz na procesy topnienia i krzepnięcia granul w trakcie obróbki termicznej.
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Experimental test results of an automatic voltage regulator with independent phase voltage controllers
PublicationThe growing number of distributed renewable energy sources and dynamic constant-power loads (e.g. electric vehicle charging stations) pose new challenges for network operators. These changes result in alterations to network load profiles and load flows, leading to greater voltage volatility. One effective solution to these problems can be the use of automatic voltage regulators (AVRs), which stabilize and symmetrize voltage output,...
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Influence of Firing Temperature on Phase Composition and Color Properties of Ceramic Tile Bodies
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