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Search results for: SHALLOW%20WATER
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CFD model and experimental verification of water turbine integrated with electrical generator
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Substance Flow Analysis of Mercury Affecting Water Quality in the European Union
PublicationW pracy zastosowano metodę SFA (Substance Flow Analysis) do oceny źródeł transportu i składowania rtęci w wodzie na terenie UE. W wyniku analizy stopnia zanieczyszczenia środowiska w przeszłości jak i scenariuszy zmian tego zanieczyszczenia w przyszłości stwierdzono, że spalanie paliw zawierających rtęć, takich jak węgiel i olej stanowi główne źródło zanieczyszczenia wody rtęcią.
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Determination of SCFAs in water using GC-FID. Selection of the separation system
PublicationIn the present study, an analytical procedure was developed for the determination of short-chain fatty acids (SCFAs) in landfill leachate and municipal wastewater employing injection of aqueous samples to gas chromatograph with flame ionization detector (GC-FID). Chromatographic conditions such as a separation system, injection volume, oven temperature program were investigated and selected. With two columns, one with a polar (polyethylene...
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Identification and antimicrobial susceptibility of fecal coliforms isolated from surface water
Publicationof 274 fecal coliforms isolated from two watercourses influencing the costal water quality of the gdańsk and the puck bay, 265 were identified as escherichia coli. the remained strains belonged to: acinetobacter spp. (n=1), enterobacter spp. (n=3), klebsiella spp. (n=4) and shigella spp. (n=1). the susceptibility of 222 e. coli was tested against 19 antimicrobial agents: aminoglycosides, carbapenems, cephalosporines, folate antagonists,...
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Contaminants in airport runoff water in the Vicinities of Two International Airports in Poland
PublicationThe general aim of the study was to evaluate environmental quality associated with the operations (combustion of fuels, cleaning of aircraft and airport aprons, aircraft, ground vehicle maintenance and repairs, fuelling operations, de/anti-icing operations) of international airports located in central and northern of Poland. These two monitoring areas were set up to monitor PAHs, PCBs, formaldehydes, phenols, detergents (cationic,...
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Performance of the flat plate solar collector operated with water-Al2O3 nanofluid
PublicationThe paper discusses the effect of application of water-Al2O3 nanofluid, as a working fluid, on the efficiency of a flat plate solar collector. The mass concentration of nanoparticles was 0.1%, 0.2% and 0.4%. The tests were conducted for two values of radiation of about 1050 W/m2 and 400 W/m2, and volume flow rates of 60 l/h, 120 l/h and 170 l/h. The efficiency was calculated according to recommendations of the Polish Standard....
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Experimental study of boiling heat transfer in the stagnation point of water microjet
PublicationIn the paper presented is a comparison of computational model with experimental data. Numerical model of liquid film with phase change in the stagnation zone due to impingement of the microjet is more widely presented in authors previous work. The radius on which theevaporation process is taking place can be determined from the energy balance on the element of the plate. That radius has also been confirmed experimentally in the...
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Quality Model for Integrated Security Monitoring and Control in Water Distribution Systems
PublicationThis article addresses the problem of drinking water distribution system (DWDS) security in the terms of water quality which in the era of terrorist threat is of high importance to the public. The contribution of this paper is the development of the so called security module to extend a multi-species water quality model. This gives an insight to the situation in DWDS not only under normal operational conditions but also in case...
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Numerical analysis of CO2-water separation in a horizontal double T-junction
PublicationCarbon dioxide is considered one of the main factors leading to global warming. Considering the significant impacts of CO2 on climate change, various technologies have been developed in recent decades to control carbon emission, such as for example CO2 capture and storage. The developed cycle of a negative CO2 emission power plant includes some devices, out of which, separator plays an indispensable role. To this end, T-junction...
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Low-energy positron collisions with water: elastic and rotationally inelastic scattering
PublicationDifferential, integral and momentum transfer cross sections for the vibrationally elastic and rotationally inelastic scattering of positrons from water at low collision energy (E ≤ 10 eV) are reported. Several models within the R-matrix method are used to compute the body-fixed T-matrices, while the scattering calculations are performed within the fixed-nuclei approximation corrected with the standard Born-closure formula. These...
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Modal analysis of a fish-belly flap type of steel water gate
PublicationABSTRACT: The results of a modal analysis of the fish-belly flap type of steel water gate are presented in the paper. The analysis was conducted for a detailed numerical model of the structure using four-node quadrilateral shell elements. The study was focused on the examination of the influence of positioning of the flap gate and hydrostatic pressure of water on the eigenvalues and eigenmodes of the structure. The results of the study...
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Assessment of the Bulgarian Wastewater Treatment Plants’ Impact on the Receiving Water Bodies
PublicationDeterioration of water quality is a major problem world widely according to many international non-governmental organizations (NGO). As one of the European Union (EU) countries, Bulgaria is also obliged by EU legislation to maintain best practices in assessing surface water quality and the efficiency of wastewater treatment processes. For these reasons studies were undertaken to utilize ecotoxicological (Microtox®, Phytotoxkit...
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A Reduction Method for Bathymetric Datasets that Preserves True Coastal Water Geodata
PublicationWater areas occupy over 70 percent of the Earth’s surface and are constantly subject to research and analysis. Often, hydrographic remote sensors are used for such research, which allow for the collection of information on the shape of the water area bottom and the objects located on it. Information about the quality and reliability of the depth data is important, especially during coastal modelling. In-shore areas are liable...
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NEW CONCEPT OF HYBRID PROPULSION WITH HYDROSTATIC GEAR FOR INLAND WATER TRANSPORT
PublicationThe article presents the development of author’s concept of a diesel/hydraulic propulsion system for inland watercraft. Due to specific nature of vessel navigation on rivers, classical propulsion systems with shaft lines can be effectively replaced by systems with hydraulic power transmission. A solution is also presented of a hybrid design with extra electric port having the form of a pumping system driven from a battery of accumulators....
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Investigation of the thermal effects in water-lubricated journal bearings with axial grooves
PublicationWater-lubricated hydrodynamic journal bearings are frequently applied as stern tube bearings due to their advantages over other bearing types. They are environmentally friendly, can operate without sealings and in conditions of low friction losses. The most popular are bearings with open axial grooves, which require, for proper operation, forced axial flow of the lubricating water. Correctly designed and operated stern tube bearings...
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Transdermal transport of collagen and hyaluronic acid using water in oil microemulsion
PublicationCollagen and hyaluronic acid (HA) are biopolymers that affect the appearance and condition of the skin. Delivery of these compounds into the skin is highly challenging since have a number of disadvantageous properties, such as high molecular weight and hydrophilicity. Here, we evaluated the transdermal penetration of low and high molecular weight collagen and HA from microemulsions. A number of microemulsion formulations, differing...
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Green products from herbal medicine wastes by subcritical water treatment
PublicationHerbal medicine wastes (HMWs) are byproducts of medicine factories, which are mainly landfilled for their environmental problems. Only bearing in mind the contamination and concerns caused by the COVID-19 pandemic and environmental emissions, the worth of herbal medicine wastes management and conversion to green products can be understood. In this work, subcritical water treatment was carried out batch-wise in a stainless tube...
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Case study of water vapour transmission properties of EPDM façade membranes
PublicationThis research aimed to investigate the water vapour transmission properties of chosen EPDM membranes applied in façade and window systems under laboratory tests. The applied procedure included in national and international standards utilized for the laboratory tests of water vapour transmission properties of EPDM membrane is described. Two main types (outside and inside types) of EPDM membranes are laboratory tested. The authors...
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Hyperbranched polyethylenimine functionalized silica/polysulfone nanocomposite membranes for water purification
PublicationHyperbranched polyethyleneimine functionalized silica (PEI-SiO2) nanoparticles with considerable hydrophilicity were synthesized and incorporated into a polysulfone (PSF)/dimethylacetamide (DMA)/polyvinylpyrrolidone (PVP) membrane casting solution in five different ratios to fabricate PEI-SiO2/PSF nanocomposite membranes using nonsolvent-induced phase separation. The hydrophilic PEI-SiO2 nanoparticles were characterized by TEM,...
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Effect of treated swimming pool water on the levels of trihalomethanes in swimmer's urine
PublicationBaseny są uważane za pierwotne źródło publicznego narażenia na trihalometany, między innymi chloroform (ma zastosowanie w dezynfekcji, a wysokie stężenia chloru są łatwo wyczuwalne zapachem). Celem badania był równoczesny przymiar poziomów THM w próbkach moczu i krwi pływaków jak również w wodzie basenowej (z miejskiego i uniwersyteckiego basenu), w celu zbadania związku między obecnością tych związków w różnych matrycach. Lotne...
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Analytical procedures for PAH and PCB determination in water samples - error sources
PublicationW pracy przedstawiono poszczególne etapy procedury analitycznej wykorzystywanej do oznaczania analitów z grupy WWA i PCB w próbkach wody. Pokazano jakie problemy występują podczas oznaczania wyżej wymienionych analitów i jaki mogą mieć wpływ na końcowy wynik analizy.
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Calibration of the Chemcatcher passive sampler for the monitoring of priority organic pollutants in water
PublicationNa Univeristy of Portsmouth (UK) opracowano próbnik pasywny typu Chemcatcher, który może być stosowany do długotrwałego monitoringu organicznych zanieczyszczeń wody. Na działanie wszystkich próbników pasywnych wpływ mają warunki środowiskowe takie jak np. ruch wody czy temperatura. Przed użyciem próbnika Chemcatcher w badaniach polowych wymagana więc była wcześniejsza kalibracja w laboratorium. Przedstawiono wyniki serii doświadczeń...
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Sources of errors associated with the determination of PAH and PCB analytes in water samples
PublicationW pracy przedstawiono problemy związane z oznaczaniem analitów z grupy WWA i PCB w próbkach wody. Zidentyfikowano źródła błędów. Szczególną uwagę zwrócono na:- proces adsorpcji analitów na ściankach szklanych naczyń używanych w trakcie obróbki i przechowywania próbek,- wpływ etapu odparowywania nadmiaru rozpuszczalnika z ekstraktów na odzysk analitów,- wpływ materiału, z którego jest wykonana kolumienka ekstrakcyjna (szkła, polietylenu)...
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Microorganisms’ communities from ballast water transferred into the Odra River estuary
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Propozycja metody oceny bezpieczeństwa użytkowania rekreacyjnego obiektu wodnego typu ‘dzika rzeka’
PublicationPrzedstawiona praca dotyczy możliwości wykorzystania numerycznej symulacji przepływu do oceny bezpieczeństwa użytkowania torów rekreacyjnych występujących w wodnych parkach rozrywki. Użytkownicy licznie odwiedzanych aquaparków oczekują wyjątkowych wrażeń z jednoczesną gwarancją bezpieczeństwa. Projektowanie tych obiektów odbywa się w oparciu o przepisy zawarte w odpowiednich normach, lecz nie są one precyzyjne. Jednak wstępną weryfikację...
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Mathematical Modeling of Ice Thrusting on the Shore of the Vistula Lagoon (Baltic Sea) and the Proposed Artificial Island
PublicationCoastal lagoons are inland and shallow water bodies, separated from the ocean by a barrier. In cold regions, ice phenomena in shallow water coastal lagoons occur every winter season. Ice is predominantly formed on the surface due to density stratification and surface cooling. The ice dynamics in such areas are dominantly affected by winds. Water dynamics also cause ice movement, but due to the large areal scale of lagoons, the...
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Characterization of PVDF/Graphene Nanocomposite Membranes for Water Desalination with Enhanced Antifungal Activity
PublicationSeawater desalination is a worldwide concern for the sustainable production of drinking water. In this regard, membrane distillation (MD) has shown the potential for effective brine treatment. However, the lack of appropriate MD membranes limits its industrial expansion since they experience fouling and wetting issues. Therefore, hydrophobic membranes are promising candidates to successfully deal with such phenomena that are typical...
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Examination of fresh water chemistry in maritime Antarctica during austral summer 2017
PublicationDue to the fact that Antarctica is one of the least polluted places on Earth, it is a perfect place to observe the spread of global pollution. Therefore, research conducted on this continent is important due to the possibility of investigating the type of pollution and their way of transport. This work considers presence of organic contaminants in Maritime Antarctica in unexplored until now, Lions Rump headland. Qualitative and...
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Fuzzy Multi-Regional Fractional PID controller for Pressurized Water nuclear Reactor
PublicationThe paper presents the methodology for the synthesis of a Fuzzy Multi-Regional Fractional Order PID controller (FMR-FOPID) used to control the average thermal power of a PWR nuclear reactor in the load following mode. The controller utilizes a set of FOPID controllers and the fuzzy logic Takagi-Sugeno reasoning system. The proposed methodology is based on two optimization parts. The first part is devoted to finding the optimal...
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Study of the Flow Dynamics of Surface Water Masses in the Area of the Coastal Gulf of Gdansk
PublicationThe paper describes two methods of predicting the movement of small objects with surface water masses. One of the methods uses graph theory to describe the motion of water masses in port docks. The results of this study were compared to a simulation using the hydrodynamic numerical model M3D. The results obtained in a virtual environment were related to the experiments in the real world. In the coastal area of the Gulf of Gdansk,...
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Water-lubricated stern tube bearing - experimental and theoretical investigations of thermal effects
PublicationThe paper presents research results of thermal phenomena accompanying operation of a water-lubricated stern tube bearing with axial grooves. Experimental tests revealed, that intensity of forced axial flow has strong influence on bush temperature. Numerical simulations focused on investigation of the thermal phenomena under operation of water-lubricated journal bearing showed, that restricted axial flow promotes backflow of the...
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Locust bean gum as green and water-soluble binder for LiFePO4 and Li4Ti5O12 electrodes
PublicationLocust Bean Gum (LBG, carob bean gum) was investigated as an environmentally friendly, natural, and water-soluble binder for cathode (LFP) and anode (LTO) in lithium-ion batteries (Li-ion). For the frst time, we show LBG as an electrode binder and compare to those of the most popular aqueous (CMC) and conventional (PVDF) binders. The electrodes were characterized using TGA/DSC, the galvanostatic charge–discharge cycle test, cyclic...
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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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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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Ultrasound-assisted heterogeneous activation of persulfate and peroxymonosulfate by asphaltenes for the degradation of BTEX in water
PublicationThis study investigated – for the first time - the simultaneous degradation of benzene, toluene, ethylbenzene and o-xylene (BTEX) by persulfate (PS) and peroxymonosulfate (PMS) activated by asphaltenes (Asph) under ultrasound (US) irradiation. Advantageous properties such as high thermal stability, low production cost and extensive availability make asphaltenes as an appealing carbonaceous material for heterogeneous catalysis....
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Spatial Analysis of Water Infrastructure Development On Example of Eastern Europe Rural Regions
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Chemometric exploration of sea water chemical component data sets with missing elements
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FEM Calculations in Analysis of Steel Subsea Water Injection Flowlines Designing Process
PublicationPaper describes the result of theoretical research aimed at assessing the loads and operating conditions of a Coiled Tubing pipeline injecting water, suspended to the mining platform of Lotos Petrobaltic. For this purpose, appropriate calculation models have been developed using the Finite Element Method (FEM), taking into account the nature of the analyzed object and its loads. The analyzes were carried out for two pipes (previously...
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Ecological bearing systems for water turbines – research and development at Gdansk University of Technology
PublicationIncreasing requirements for environmental protection make it necessary to introduce new materials and designs. Hydroelectric power plants operating in direct contact with water reservoirs and rivers are potentially endangering water cleanliness, hence they should also be modernized in the way minimizing the environmental hazards. A lot of progress in this field has been achieved in last decades, but still there is much work to...
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Free convection of water-Al2O3 nanofluid from horizontal porous coated tube
PublicationThe main aim of the present study was to investigate the influence of nanoparticles on heat transfer coefficients during free convection of water-Al2O3 nanofluid from horizontal porous coated tube under atmospheric pressure for nanoparticle concentration of 0.01% by weight. Contrary to published data present study concerns on free convection of nanofluids in extensive, quiescent fluid.
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Polychlorinated Biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs): Sediments and Water Analysis
PublicationUnfavorable side effects of different forms of anthropogenic activities can be found anywhere in the world. One of the basic characteristics of pollutants entering marine and ocean waters is their spread and movement in the global ocean. A portion of the substances entering the marine environment is rapidly degraded by chemical processes occurring in the air, sediments, and water, thereby losing their toxic properties. The biggest...
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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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Influence of dissolved organic matter in natural and simulated water on the photochemical decomposition of butylparaben
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Exploring Solanum tuberosum Epoxide Hydrolase Internal Architecture by Water Molecules Tracking
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Ionic liquids for the passive sampling of sulfonamides from water—applicability and selectivity study
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Salinity and pH as factors affecting the passive sampling and extraction of pharmaceuticals from water
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Size-dependent effects of ZnO nanoparticles on the photocatalytic degradation of phenol in a water solution
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Static and dynamic superheated water extraction of essential oil components fromThymus vulgarisL.
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Problems of inland navigation in Poland in view of integrated water resources management (IWRM)
PublicationW artykule przedstawiono zasady zintegrowane zarządzania gospodarką wodna. Przedstawiono rolę żeglugi środlądowej w gospodarce wodnej Polski i krajów czlonkowskich Unii Europejskiej. Przedstawiono aktualny stan dróg wodnych w Polsce, ograniczenia rozwoju i perspektywy na przyszłośc z punktu widzenia ZZGW.