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Search results for: MECHANIZM OF FREEZING OF WATER
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Nodal models of Pressurized Water Reactor core for control purposes – A comparison study
PublicationThe paper focuses on the presentation and comparison of basic nodal and expanded multi-nodal models of the Pressurized Water Reactor (PWR) core, which includes neutron kinetics, heat transfer between fuel and coolant, and internal and external reactivity feedback processes. In the expanded multi-nodal model, the authors introduce a novel approach to the implementation of thermal power distribution phenomena into the multi-node...
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Approximate solution for Euler equations of stratified water via numerical solution of coupled KdV system
PublicationWe consider Euler equations with stratified background state that is valid for internal water waves. The solution of the initial-boundary problem for Boussinesq approximation in the waveguide mode is presented in terms of the stream function. The orthogonal eigenfunctions describe a vertical shape of the internal wave modes and satisfy a Sturm-Liouville problem. The horizontal profile is defined by a coupled KdV system which is...
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LDFEM analysis of pore water pressure development in cohesive soil due to FDP auger drilling
PublicationThis paper presents the preliminary modelling of FDP auger drilling in soft soil with emphasis on excess pore water pressure (EPWP) development using CEL formulation and Abaqus software suit. The EPWP generation in single points is investigated and the results of a numerical analysis are compared with the field measurements. It is found that numerical model qualitatively reflects the field measurements. However,...
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Evaluation of reverse osmosis for improving quality of water utilized in hemodialysis devices (case study: Kerman University of Medical Sciences' hospitals).
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Contamination of Runoff Water at Gdańsk Airport (Poland) by Polycyclic Aromatic Hydrocarbons (PAHs) and Polychlorinated Biphenyls (PCBs)
PublicationAirport runoff can contain high concentrations of various pollutants, in particular polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), the environmental levels of which have to be monitored. Airport runoff water samples, collected at the Gdańsk-Rębiechowo Airport from 2008 to 2009, were analysed for PAHs and PCBs by gas chromatography. The aromatic fractions were separated by liquid-liquid extraction...
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Assessment of Surface Water Resources Based on Different Growth Scenarios, for Borkena River Sub-basin, Awash River Basin, Ethiopia
PublicationThe total annual river flow at the Awash Kombolcha sub-basin of the Borkena river station was estimated to be 4.6 billion cubic meters by 2019-2030. The current average annual flow at the exit measurement station is 544.5Mm3 of the water resources available in the study area. The monthly peak flow of the Borkena River occurs from July to September. In addition, the highest monthly average flow is in August and the lowest is...
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Assessment of the factors influencing on the formation of energy-oriented modes of electric power consumption by water-drainage installations of the mines
PublicationPurpose. Performing the analysis to determine energy-efficient modes and assess the characteristics of the main indicators of electric power consumption by mine water-drainage installations based on the developed research mathematical model. Methods. To achieve the purpose set, a methodology is used to develop the multiple multifactor correlation-regression modeling with respect to the modes of electric power consumption by electrical...
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Hydrostatically discharged commutation unit and it's impact on axial pump's performance
PublicationW pracy przedstawiono wyniki analizy teoretycznej funkcjonowania rozrządu czołowego i hydrostatycznie odciążonego rozrządu krzywkowego w pompach wielotłoczkowych osiowych. Zaprezentowano także wyniki porównawczych badań sprawności mechaniczno-ciśnieniowej, objętościowej i całkowitej dla pomp o różnej konstrukcji. Podano informacje o produkowanych obecnie pompach typu PWK.
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Preparation of platinum modified titanium dioxide nanoparticles with the use of laser ablation in water
PublicationWe report on the preparation method of nanocrystalline titanium dioxide modified with platinum by using nanosecond laser ablation in liquid (LAL). Titania in the form of anatase crystals has been prepared in a two-stage process. Initially, irradiation by laser beam of a titanium metal plate fixed in a glass container filled with deionized water was conducted. After that, the ablation process was continued, with the use of a platinum...
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Enhanced cellulose extraction from agave plant (Agave americana Species) for synthesis of magnetic/cellulose nanocomposite for defluoridation of water
PublicationResearch on fluoride removal from water is currently focusing on the development of innovative materials for defluoridation water. The current study extracted and used enhanced cellulose from Agave americana species to synthesize a magnetic/cellulose nanocomposite for water defluoridation. Strong and light binary acids (H2SO4 and CH3COOH) were utilized to pretreat raw material to enhance cellulose extraction. Central composite...
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Interval estimator for chlorine monitoring in drinking water distribution systems under uncertain system dynamics, inputs and state measurement errors
PublicationThe design of interval observer for estimation of unmeasured state variables for application to drinking water distribution systems is described in this paper. In particular, it considers the design of such observer for estimation of water quality described by free chlorine concentration. An interval observer is derived to produce robust interval bounds on the estimated water quality state variables. The stability and robustness...
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Ecological bearing systems for water turbines - two research programs aimed at making water turbines more "eco-friendly".
PublicationW pracy opisano próby wyeliminowania ropopochodnych środków smarowych z układów łożyskowania turbin wodnych. Próby dotyczą zastosowania bezsmarowych łożysk kierownic i smarowanych wodą łożysk wałów turbin. Wprowadzanie bezsmarowych łożysk kierownic wymaga stworzenia metod prognozowania ich trwałości w warunkach małych oscylacji. Do stosowania w łożyskach wałów zaproponowano smarowane wodą łożyska ceramiczne o oryginalnej konstrukcji,...
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Pool boiling heat transfer of water-Al2O3 and water-Cu nanofluids on horizontal stainless steel smooth and rough tubes
PublicationPrzedstawiono wyniki badań eksperymentalnych przejmowania ciepła przy wrzeniu nanocieczy woda-Al2O3 i woda-Cu na poziomych rurkach ze stali nierdzewnej. Ustalono, że niezależnie od badanej koncentracji nanocząstek (0.01%, 0.1% oraz 1%) współczynnik przejmowania ciepła dla nanocieczy był wyższy niż dla wody i rósł ze wzrostem koncentracji. Ponadto współczynnik przejmowania ciepła dla nanocieczy wzrastał ze wzrostem ciśnienia.
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Friction and wear behaviour of self mated DLC and DLC-W coatings in water or salt in water solution lubricated sliding
PublicationPrzedstawiono wyniki badań powłok ceramicznych DLC oraz DLC z wolframem (DLC-W) nałożonych na podłoże ze stali nierdzewnej,przy tarciu ślizgowym , w modelowym skojarzeniu o styku konforemnym (płaskie czoło obracającej się względem swojej osi tulei - powierzchnia płaska). Badania prowadzono stosując smarowanie wodą destylowaną albo wodnym roztworem soli - NaCl. Wyznaczano współczynniki tarcia oraz intensywność zużywania ceramicznej...
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Optimizing control by robustly feasible model predictive control and application to drinking water distribution systems
PublicationThe paper considers optimizing Model Predictive Control (MPC) for nonlinear plants with output constraints under uncertainties. Although the MPC technology can handle the constraints in the model by solving constraint model based optimization task, satisfying the plant output constraints under the model uncertainty still remains a challenge. The paper proposes Robustly Feasible MPC (RFMPC), which achieves feasibility of the outputs...
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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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Multi-stage magnetic-fluid seals for operating in water - life test procedure, test stand and research results. Part II Results of life tests of multi-stage magnetic - fluid seal operating in water
PublicationThe edge criteria for magnetic-fluid seals durability research were described in previous article [24] and now the tests results are presented. The tests were made with three magnetic fluids using various magnets quantity in magnetic assemblies. If values obtained in the repeated test deviated by more than 10 % from results of the first test an additional control test was made for final characteristics. The characteristics are:...
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The use of RP-HPLC–Q-TOF–MS as a powerful tool for wastewater composition profiling and selection of water pollution marker specific to wastewater contamination
PublicationLimited drinking water resources and water pollution are one of the main worldwide problems. To reduce the consumption of fresh water resources, the use of treated wastewater has been proposed. The farmlands have been irrigated with wastewater for centuries, but the composition of used sewage has changed over the years. Recent research has revealed the presence of hundreds of new organic contaminants in many environmental waters,...
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Water uptake kinetics and electrical transport in BaCe0.6Zr0.2Y0.1M0.1O3−δ (M = Tb, Pr, Fe) protonic conductors
PublicationBaCe0.6Zr0.2Y0.1M0.1O3−d (M = Fe, Pr, Tb) is a mixed conducting oxide in which three mobile charge carriers – oxygen ion, electron/hole, and protonic defects – are present. These types of materials have gained much interest as electrode materials for protonic ceramic fuel cells (PCFCs) and protonic ceramic electrolysis cells (PCECs). In this study, the water uptake and oxygen transport properties of different BaCe0.6Zr0.2Y0.1M0.1O3−d...
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Improved Empirical Coefficients for Estimating Water Vapor Weighted Mean Temperature over Europe for GNSS Applications
PublicationDevelopment of the so-called global navigation satellite system (GNSS) meteorology is based on the possibility of determining a precipitable water vapor (PWV) from a GNSS zenith wet delay (ZWD). Conversion of ZWD to the PWV requires application of water vapor weighted mean temperature (Tm) measurements, which can be done using a surface temperature (Ts) and its linear dependency to the Tm. In this study we analyzed up to 24 years...
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Effect of Impoundment on Physico-chemical Properties of Water in the Flowing through stream, the Case of the Turawa Reservoir
PublicationThe Turawa reservoir is one of the most important storage reservoirs in Poland. Quite many physico-chemical parameters of water in the reservoir itself and also in the Mała Panew, the river flowing through the reservoir were measured at various periods of the year. Measuring and sampling points were situated at the river inflow, over the reservoir, and at the river outflow. The parameters included temperature, electrical conductivity,...
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Experimental study of pressure rise at the evaporator of capillary pumped loop with acetone and water as working fluids
PublicationIn this work studied is the possibility of fluid pumping using capillary forces in the capillary pumped loop. Experimental and theoretical studies have been performed to understand the phenomena associated with heat transfer in porous structure of the evaporator. The capillary effect was studied during operation of two different capillary porous structures with two different working fluids, namely water and acetone. The results...
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Comparison of heat transfer characteristics in surface cooling with boiling microjets of water, ethanol and HFE7100
PublicationThe basis of microjet technology is to produce jets which impinge the surface at the stagnation point with a very high kinetic energy. Main objective of this paper was to investigate the physical phenomena occurring on solid surfaces upon impingement of the single microjet in case of three fluids, namely water, ethanol and HFE7100. Intense heat transfer in the impact zone of microjet has been examined and described with precise...
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Determination of selected chemical parameters in surface water samples collected from the Revelva catchment (Hornsund fjord, Svalbard)
PublicationSurface water samples (river and lake) were collected from the Revelva catchment every summer from 2010 to 2013. This study concerns importance of the use of some analytical techniques for pollutants and parameters deter- mination in Arctic environmental samples based on the example of total organic carbon, phenols, and formaldehyde determination and measurement of pH and electrical conductivity parameters. Significant...
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The modelling and enhancement of water hydrodynamics: general discussion
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Applications of water molecules for analysis of macromolecule properties
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Current Issues in Pharmaceutical Residues in Drinking Water
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Passive sampling techniques for monitoring pollutants in water
PublicationPraca przeglądowa poświęcona technice dozymetrii pasywnej. Omówiono charakterystykę wybranych próbników pasywnych wykorzystywanych w analityce zanieczyszczeń wody. Ponadto przedstawiono zalety i wady technik pasywnych oraz opisano obszar praktycznego zastosowania próbnikow pasywnych.
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Biodegradability of polyethylene starch blends in sea water
PublicationPrzedmiotem badań podatności na biodegradację w wodzie morskiej były próbki polietylenu i polietylenu modyfikowanego skrobią. Próbki te badano także w wodzie morskiej z azydkiem sodu, aby ocenić ich odporność na hydrolizę. Testy przeprowadzano w okresie 20 miesięcy. Oceniano zmiany ubytku wagi, właściwości wytrzymałościowych i morfologii przed i po procesie degradacji.
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Water resources security and management for sustainable communities
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Water Interactions with Hydrophobic versus Hydrophilic Nanosilica
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Water needs of production of biomass for energy in Poland
PublicationPrzedstawiono polskie zamierzenia polityczne dotyczące rozwoju produkcji biomasy do celów energetycznych. Produkcja biomasy wymagać będzie zwiększonego zużycia wody przez rośliny. Wprawdzie w Polsce potrzeby wodne roślin energetycznych będą 2-3 krotnie niższe niż w krajach śródziemnomorskich, tym niemniej opady atmosferyczne w Polsce będą niewystarczające i potrzeby wodne wymagać będą nawodnień na poziomie 50% aktualnych opadów...
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Carbon modified TiO2 photocatalysts for water purification
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The Water Needs of Grapevines in the Different Regions of Poland
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Chemical pretreatment of feed water for membrane distillation
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Water demineralisation by NF/MD integrated processes
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The Benefits of Using Saccharose for Photocatalytic Water Disinfection
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Effectiveness of Water Desalination by Membrane Distillation Process
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Behaviour of water in different types of goats' cheese
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Simulation of water turbine integrated with electrical generator
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Mercury emission to air, water and soil in Poland
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Superhalogen oxidizers capable of ionizing water molecules
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Water properties in pâtés enriched with potato juice
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Early urban water management of Gdansk, Poland
PublicationWczesna gospodarka wodą w Gdańsku, warunki powstania, znaczenie historyczne. Rozwój wodociągów i kanalizacji w mieście. Aktualne warunki rozwoju, specyfika Gdańska.
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Hydrodynamic Pressure Field of a Ship on Shallow Water
PublicationResults of calculations of the hydrodynamic pressure field around the ship were obtained by application of the boundary element method. Hydrodynamic field was calculated for a Polish Navy’s tugboat and transport ship using a program called SHiPP and compared with measurements of the field taken on river near Swinoujscie for two identical tugs H-4 and H-10. Next, a series of HPF calculations was carried out on planes situated at...
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Architecture and water - new concepts of blurring borders
PublicationArtykuł ukazuje współczesne relacje pomiędzy architekturą i wodą na tle przełomowej myśli teoretycznej wczesnego modernizmu i koncepcji sztuki XX wieku.
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Experimental and theoretical study of protonated water cluster
PublicationZa pomocą metody rojowej zbadano powstanie i dryf dodatnio naładowanych klastrów wody H+(H20)n n=1-7. Oszacowano energie dysocjacji. Prace uzupełniają obliczenia kwantowe konfiguracji wybranych klastrów. Dokonano obliczeń kilkunastu konfiguracji zjonizowanych klastrów.
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Water hammer analysis in two pipes in series
PublicationW pracy przedstawiono wyniki badań laboratoryjnych przepływu nieustalonego w rurociągu skokowo zmiennej średnicy. Dokonano porównania czynników pomiarów oraz obliczeń uderzenia hydraulicznego zmodyfikowaną metodą elementów skończonych.
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Stepless control in water supply and sewage system
PublicationPrzedstawiono metody oraz zalety płynnego sterowania przepływami w systemachwodociągowych i kanalizacyjnych poprzez płynną regulację wydajności pompow-ni. Opierając się na przeprowadzonych symulacjach komputerowych opisano ty-powe przypadki sterowania i wskazano rozwiązania optymalne. Analizowane pły-nne sterowanie porównano z analogicznymi sterowaniami tradycyjnymi opartymio regulację dwustawną.
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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...