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Space-Time Conservation Method applied to numerical solution of water hammer equations
PublicationArtykuł poświęcony jest metodzie czasoprzestrzennych objętości skończonych (STC) zastosowanej do przypadku uderzenia hydraulicznego w stalowym przewodzie pracującym pod ciśnieniem. Metoda STC ze względu na swoje własności numeryczne - m.in. wysoką dokładność - może być interesującą alternatywą dla tradycyjnych metod numerycznych, szczególnie w przypadku, gdy efekty numeryczne mają bardzo silny wpływ na rozwiązanie, tym samym utrudniając...
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Operating and economical conditions of cooling water control for marine steam turbines condensers
PublicationW pracy dokonano analizy ekonomicznej i eksploatacyjnej sterowania pracą pomp wody chłodzącej skraplacze turbin okrętowych. Wzięto pod uwagę cechy konstrukcyjne pomp wody chłodzącej skraplacze główne i najnowsze wyniki badań dla takich pomp w zastosowaniach lądowych. Uwagę skupiono przede wszystkim na turbinowych parowych siłowniach okrętowych.
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Water Solubilization Using Nonionic Surfactants from Renewable Sources in Microemulsion Systems
PublicationIn this study the effect of temperature, NaCl andoils (hydrocarbons: C8-C16) on the formation and solubilizationcapacity of the systems of oil/monoacylglycerols(MAG):ethoxylated fatty alcohols (CEO20)/propylene glycol(PG)/water was investigated. The effects of the surfactantmixture on the phase behavior and the concentration ofwater or oil in the systems were studied at three temperatures(50, 55, 60 C) and with varied NaCl solutions...
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Determination of Selected Organic Acids in Animal Farm Water Samples by Ion Chromatography
PublicationLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments due to natural processes and human activity. They are an important group of organic pollutants of waste water that mainly includes, volatile fatty acids, and also dicarboxylic, aromatic, hydroxy- and ketoacids. LCAs are present in the environment at concentrations between 1 to 5000 ppm and different methods have been reported for their determination...
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Possible application of new class of solvents in the purification of water used in hydraulic fracturing
PublicationNowym źródłem energii niekonwencjonalnej w Polsce może być gaz, który jest uwięziony w łupkach. Podczas poszukiwań gazu łupkowego, duże ilości wody wykorzystywanej w procesie szczelinowania hydraulicznego powracają na powierzchnię zanieczyszczone. Istnieje wiele metod usuwania śladowych ilości węglowodorów tj. fizyczne czyli filtracja czy chemiczne czyli zakwaszanie, ale mogą one być nieskuteczne. Pożądana metoda to monitorowanie...
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Hydrogen assisted cracking of 2205 duplex stainless steel in synthetic sea water
PublicationThe cracking behavior of 2205 duplex stainless steels (DSSs) in synthetic sea water under cathodic polarization condition was investigated. (SSRT) method was employed in aim to evaluate the susceptibility to hydrogen assisted cracking. The results showed that the reduction in the uniform elongation (UEL) and the reduction of area (RA) varied with the applied cathodic current density. Significant reductions in ductility were found,...
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Determination of metals in water samples by atomic absorption spectrometry and flame emission spectrometry
PublicationMetal species in environmental waters are relevant to characterize the metal toxicity, the mobility between different environmental compartments, and for remediation purposes in case of contamination. The concentration of many trace metals in natural water samples are generally at µg/l level. The paper describes determination of metals in water samples based on flame atomic emission and flame atomic absorption spectrometry.
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Investigation of the distribution of imidazolium ionic liquids in the environment - aggregation in water and sorption on minerals
PublicationWpływ cieczy jonowych na środowisko, a w szczególności: migracja do wód powierzchniowych i gruntowych, jak również transport/retencja w gruntach jest determinowany przede wszystkim przez właściwości fizykochemiczne cieczy jonowej jak i właściwości matrycy środowiskowej. Znajomość zjawisk zachodzących w wyniku kontaktu cieczy jonowych z wodą oraz glebą jest jednym z podstawowych warunków oceny ryzyka chemicznego. W pracy wykazano,...
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A Comparison of Simplified Two-dimensional Flow Models Exemplified by Water Flow in a Cavern
PublicationThe paper shows the results of a comparison of simplified models describing a two-dimensional water flow in the example of a water flow through a straight channel sector with a cavern. The following models were tested: the two-dimensional potential flow model, the Stokes model and the Navier-Stokes model. In order to solve the first two, the boundary element method was employed, whereas to solve the Navier-Stokes equations, the...
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Improvement of S355G10+N steel weldability in water environment by Temper Bead Welding
PublicationThe normalized S355G10 + N steel was chosen for testing, it is used in a variety of applications including the building of offshore structures, which may require repairs in water environment. The main aim of the work was to check susceptibility to cold cracking for fillet welds – Controlled Thermal Severity (CTS) tests and butt welds – Tekken tests and in the next step evaluation of effectiveness of Temper Bead Welding (TBW) application...
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Water uptake in protective organic coatings and its reflection in measured coating impedance
PublicationWater uptake in commercially available epoxy coating on mild steel using impedance spectroscopy and gravimetry was studied. The water content in the coating was determined using the Brasher-Kingsbury equation and various methods of coating capacitance calculation used in the literature. The obtained results were compared with reference gravimetric data. An overestimation of values obtained from impedance data in relation to gravimetric...
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Direct algorithm for optimizing robust MPC of drinking water distribution systems hydraulics
PublicationModel-based predictive control is an effective method for control the large scale systems [1]–[6], [8], [16], [17]. Method is based on on-line solution of the control task over the control horizon using current and past measurements, as well as the system model. Only a first element of calculated control sequence is applied to the plant. At the next sampling instant, based on new process output measurements, control procedure is...
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New Generation of Water lubricated Foil bearing - Numerical Models and Experimental Verification
PublicationIn the paper a new idea of foil water lubricated bearing and methodology of hydrodynamic characteristics calculations is presented. To assesses the theoretical characteristics of these bearings two different computer models were built. First is structural model coupled with fluid model. It takes into account: fluid flow in the deformed fluid gap, specific design of bearing support and friction in bearing support. The second is...
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Study of the formation of calcareous deposits on cathodically protected steel in Baltic sea water
PublicationPurpose – The purpose of this paper is to investigate whether the sedimentation of calcareous deposits occurs on cathodically protected steel in Baltic sea water. Design/methodology/approach – Steel electrodes were cathodically polarized in natural Baltic sea water at potential þ0.150 V vs Zn electrode in potentiostatic mode. During exposure chronoamperometric measurements were carried out. After the exposure, the electrode’s surface...
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The effect of chlorinated drinking water consumption on levels of volatile organohalogen compounds in urine.
PublicationW przedstawionej pracy podjęto próbę oznaczenia niezmienionych form lotnych rozpuszczalników chlorowcoorganicznych w próbkach materiału biologicznego jakim jest mocz dawców, używających w gospodarstwie domowym a także w pracy wody uzdatnianej między innymi w procesie chlorowania. Do wykonania oznaczeń zastosowano zmodyfikowaną technikę analizy fazy nadpowierzchniowej nad cienką warstwą cieczy z samoczynną generacją ciekłego sorbentu...
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Characteristics of the Lakes in Radunia River catchment according to the EU Water Framework Directive
PublicationPrzedstawiono charakterystykę hydrologiczną Raduni i jej dopływów. Określono typologię jezior zlokalizowanych w zlewni zgodnie z wymogami Ramowej Dyrektywy wodnej UE.
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COMPARATIVE ANALYSIS OF TRANSPORT ORGANIZATION AND FUNCTIONING OF WATER TRAMS IN GDAŃSK, BYDGOSZCZ AND KRAKÓW
PublicationThe subject of this work is to identify and juxtapose solutions implemented in transport provided by water trams for the following cities: Gdańsk, Bydgoszcz and Kraków. As a result of the conducted analysis of transport factors, the degree of conformity of project objectives to the actual role of the water tram has been determined. It was found that the Kraków Water Tram (also known as Cracow Water Tram) is characterized by the...
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Experimental investigation of forced convection of water-Al2O3 nanofluids inside horizontal tubes,
PublicationIn this paper, forced convection of water–Al2O3 nanofluids inside horizontal copper tube is studied experimentally. Experiments were conducted for three, i.e. 0.1%, 1% and 5% nanoparticle mass concentrations under transition and turbulent flow regimes. Average heat transfer coefficients and pressure drop values were determined and compared to distilled water. Enhancement of heat transfer for lower nanoparticle concentration and...
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Magnetic semiconductor photocatalysts for the degradation of recalcitrant chemicals from flow back water
PublicationIn the present study treatability of persistent organic compounds from the flow back water after hydrauling fracturing was investigated. The combination of TiO2 photocatalyst and magnetic oxide nanoparticles enhance the separation and recoverable property of nanosized TiO2 photocatalyst. Fe3O4/ TiO2 and Fe3O4@SiO2/TiO2 nanocomposites were prepared by heteroagglomeration. The photocatalysts’ characteristics by X-ray diffractometry...
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Donor properties of water in organic solvents derived from infrared spectraof HDO
PublicationPrzedyskutowano niektóre ilościowe aspekty kooperatywności wiązań wodorowych wody. Zaproponowano skalę własności elektronodonorowych wody w środowisku aprotycznych rozpuszczalników organicznych, pochodną w stosunku do skali liczb donorowych Gutmanna.
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Assessment of the Current Potential of Hydropower for Water Damming in Poland in the Context of Energy Transformation
PublicationThe present paper indicates that hydropower, including small hydropower plants (SHPs), may play a very important role in Poland’s energy transformation in the near future. The development of SHPs may also increase water resources in the steppe Poland. Additionally, the aim of the present research is to conduct the PEST analysis of SHPs in Poland, taking into account the SHP potential. For the first time, maps showing the power...
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Degradation of 1,4-dioxane by sono-activated persulfates for water and wastewater treatment applications
PublicationThis paper presents a hybrid advanced oxidation process (AOP) based on sonocavitational activation of persulfate (PS) for degradation of 1,4-dioxane during wastewater treatment. Application of sono-cavitation effectively convert PS to radical species demonstrating synergistic effect by increasing the reaction rate and reducing the required energy for activation. It is economically feasible and deployed alternative to the direct...
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Synergistic effects of nitrogen-doped carbon and praseodymium oxide in electrochemical water splitting
PublicationHybrid materials featuring perovskite-type metal oxide in conjunction with heteroatom-doped graphene hold immense promise as alternatives to costly noble metal catalysts for electrochemical water splitting, facilitating the generation of environmentally friendly hydrogen. In this study, perovskite-type oxide containing praseodymium, barium, strontium, cobalt, and iron atoms dispersed in a carbon matrix as a catalyst is synthesized...
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Bismuth-based nanomaterials-assisted photocatalytic water splitting for sustainable hydrogen production
PublicationThe rapidly increase in the world's population has resulted in a corresponding increase in the energy demand. This demand is largely being met by fossil fuels for power generation, industrial fuel and transportation. However, due to the limited availability of fossil fuels and their negative effects on the environment. The use of fossil fuels results in by-products such as carbon, nitrogen and sulfur oxides which have negative...
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The Application of a Mobile Unmanned Device for Monitoring Water and Sediment Pollution in the Port of Gdynia
PublicationPollution in the Port of Gdynia can encompass various types of substances and contaminants that affect the quality of water and sediment in this region. Ships entering and leaving the port can release pollutants such as oil, fuel, waste, and chemicals into the water. Controlling and monitoring these pollutants is a crucial part of environmental stewardship. In recent years, uncrewed units have been increasingly in use for in situ...
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Ti-Fe2O3/In2O3 as photoactive material: The role of the substrate in photoelectrochemical water oxidation
PublicationThe layers of Ti-Fe2O3/In2O3 were prepared on the different substrates using hydrothermal method: Ti/TiO2 nanotubes, Ti foil, FTO and FTO/TiO2. Materials were characterized using scanning electron microscopy, XRD, Raman, UV-Vis, and X-ray photoelectron spectroscopy and tested as photoanodes for water oxidation under illumination. The formation of heterojunction on the TiO2 nanotubes increases photocurrent of water oxidation at...
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Water-Lubricated Journal Bearings Marine Applications, Design, and Operational Problems and Solutions
PublicationWater-Lubricated Journal Bearings: Marine Applications, Design, and Operational Problems and Solutions provides cutting-edge design solutions, common problems and methods for avoiding them, and material selection considerations for the use of water-lubricated journal bearings in marine environments. These bearings have many advantages, including the absence of the potential for oil contamination. They are also sensitive, and their...
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Bismuth-based nanomaterials-assisted photocatalytic water splitting for sustainable hydrogen production
PublicationThe rapidly increase in the world's population has resulted in a corresponding increase in the energy demand. This demand is largely being met by fossil fuels for power generation, industrial fuel and transportation. However, due to the limited availability of fossil fuels and their negative effects on the environment. The use of fossil fuels results in by-products such as carbon, nitrogen and sulfur oxides which have negative...
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Detection of People Swimming in Water Reservoirs with the Use of Multimodal Imaging and Machine Learning
PublicationEvery year in many countries, there are fatal unintentional drownings in different water reservoirs like swimming pools, lakes, seas, or oceans. The existing threats of this type require creating a method that could automatically supervise such places to increase the safety of bathers. This work aimed to create methods and prototype solutions for detecting people bathing in water reservoirs using a multimodal imaging system and...
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Stability studies of selected phenoxyacid herbicides in water samples and detrmination of their transformation products
PublicationZbadano procesy przemian fenoksykwasów (takich jak: 2,4-D, MCPA, mekoprop, dichlorprop) w różnych roztworach wodnych. Sprawdzono wpływ parametrów (światło, temperatura oraz czas przechowywania próbki) na stabilność fenoksykwasów. Oznaczeń końcowych dokonano przy użyciu techniki chromatografii cieczowej sprzężonej ze spektrometrem mas.
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Integrated approach for evaluation of pollution level of underground water in the vicinity of a municipal landfill
PublicationCelem pracy była ocena stopnia zanieczyszczenia wód podziemnych pobranych wokół składowiska odpadów komunalnych. Zastosowano zintegrowane podejście polegajace na jednoczesnym wykorzystaniu badań chemicznych i biotestów. Najbardziej zanieczyszczone próbki okazały się również najbardziej toksyczne wobec badanych organizmów wskaźnikowych. Wykorzystanie biotestów umożliwia uzyskanie dodatkowej informacji na temat możliwych skutków...
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The state of the art in the field of decrease the pollution in the South Baltic area
PublicationVarious form of human activity such as maritime transports, industrial activities, busy traffic, intensive farming and animal husbandry can have negative impact on natural marine environment. Baltic Sea catchment area is characterized by the high river water flux and wastewater treatment plants discharges. Additionally, the limited shallow connection to the North Sea results in little water exchange and residence time of approximately...
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Changes in conditions of acoustic wave propagation in the Gdansk deep as an effect of climate changes in the Baltic Sea region
PublicationThe article presents the results from a research project investigating acoustic climate changes in the Gdansk Deep based on data extending from 1902 to 2019. This part of the southern Gotland Basin, is rarely discussed in the scientific literature. The speed of sound in the seawater is a function of temperature, salinity, and depth. In such shallow sea as Baltic Sea, the impact of depth is not substantial. The other two factors...
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Numeryczna analiza hydrauliki toru kajakarstwa górskiego w Drzewicy
PublicationW artykule zaproponowano wykorzystanie do analizy hydrodynamiki toru kajakarstwa górskiego symulacji numerycznej, wykorzystującej dwuwymiarowe równania ruchu wody w warunkach przepływu szybkozmiennego. Rozwiązanie równań hydrodynamiki wykonano samodzielnie z zastosowaniem metody objętości skończonych. Jako przykład zastosowania zaproponowanej metody przedstawiono analizę przepływu wzdłuż istniejącego, poddanego modernizacji toru...
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The Efficiency of P-Removal from Natural Waters with Sorbents Placed in Water Permeable Nonwovens
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The Influence of the Soil Environment on the Corrosivity of Failure Infrastructure - Case Study of the Exemplary Water Network
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The Water Requirements of Grapevines (Vitis vinifera L.) Under Climatic Conditions of Central Poland
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Upcycle waste plastics to magnetic carbon materials for dye adsorption from polluted water
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Water Behavior of Aerogels Obtained from Chemically Modified Potato Starches during Hydration
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Triticale extrudates – Changes of macrostructure, mechanical properties and molecular water dynamics during hydration
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MEL zeolite nanosheet membranes for water purification: insights from molecular dynamics simulations
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Effects of different defective linkers on the photocatalytic properties of Cu-BTC for overall water decomposition
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Precise regulation of defect concentration in MOF and its influence on photocatalytic overall water splitting
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Nickel loaded zeolites FAU and MFI: Characterization and activity in water-phase hydrodehalogenation of TCE
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Water and chemical input via hydrometeors in central european mountains with Szrenica Mt. as an example
PublicationZanieczyszczenia obecne w powietrzu atmosferycznym są transportowane do powierzchni ziemi przy pomocy osadów atmosferycznych. Celem pracy było przedstawienie chemizmu różnych typów osadów atmosferycznych. Badania prowadzono na szczycie góry Szrenicy. Badania prowadzono od grudnia 2008 do lutego 2010. Przedstawiono wyniki analiz przeprowadzonych dla różnego typu osadów występujących na tym terenie.
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Comprehensive circumscribing of non-linearity cases of a water supply system with smooth flow control
PublicationW artykule opisano formalnie poprawne metody opisu matematycznego pracy pomp o płynnie regulowanych wydatkach oraz reduktorów ciśnienia i reduktorów przepływu w modelowaniu przepływów ustalonych zachodzących w systemach wodociągowych. Opisano metodę opartą o dynamiczną analizę wrażliwości systemu oraz metodę wykorzystującą charakterystyki hydrauliczne systemu wodociągowego. Przedstawiono wyniki symulacji wykorzystującej ww. metody...
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Simulation of water flow in double -porosity soils on unstructured grids with the finite element method.
PublicationRozważa sie model przepływu wody w gruntowym ośrodku o podwójnej porowatości. Model matematyczny uzyskano poprzez zastosowanie teorii homogenizacji zastosowanej do gruntów o bardzo dużej różnicy przepuszczalności.
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Concept of implementation of open water model tests for assessment of safety of ships in damaged conditions
PublicationPraca zawiera opis koncepcji zastosowania badań modelowych na wodach otwartych w odniesieniu do oceny bezpieczeństwa statków w stanie uszkodzonym. Badania modelowe w omawianym zakresie mogą stanowić alternatywną metodę oceny bezpieczeństwa statków w stanie uszkodzonym lub mogę służyć do weryfikacji oceny bezpieczeństwa statków w stanie uszkodzonym, przeprowadzonej za pomocą metody zawartej w zharmonizowanej wersji konwencji SOLAS...
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Effects of water level and grassland management on alpha and beta diversity of birds in restored wetlands
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WATER QUALITY PARAMETERS OF A SMALL MIDFOREST WATERCOURSE RECEIVING DOMESTIC SEWAGE AFTER TREATMENT
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