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Search results for: CHANGES OF WATER CHARACTERISTICS
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Carbon Dioxide and Water Vapour Fluxes of a Alkaline Fen and Their Dependence on Reflectance
PublicationThis study shows results of parallel measurements of greenhouse gases fluxes (carbon dioxide and water vapour) and canopy reflectance of alkaline fen. Fluxes were measured using eddy-covariance technique on micrometeorological station located in the Upper Biebrza Basin (NE Poland) in Rogożynek Village. Study site is located in the Biebrza National Park which was established to protect one of the biggest coherent lowland wetland...
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Leakage detection and localisation in drinking water distributionnetworks by MultiRegional PCA
PublicationMonitoring is one of the most important steps in advanced control of complex dynamic systems. Precise information about systems behaviour, including faults indicating, enables for efficient control. The paper describes an approach to detection and localisation of pipe leakage in Drinking Water Distribution Systems (DWDS) representing complex and distributed dynamic system of large scale. Proposed MultiRegional Principal Component...
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Comparison of state feedback and PID control of pressurizer water level in nuclear power plant
PublicationThe pressurizer water level control system in nuclear power plant with pressurized water reactor (PWR) is responsible for coolant mass balance. The main control goal is to stabilize the water level at a reference value and to suppress the effect of time-varying disturbances (e.g. coolant leakage in primary circuit pipeline system). In the process of PWR power plant operation incorrect water level may disturb pressure control or...
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Balance errors in numerical solutions of shallow water equations
PublicationThe analysis of the conservative properties of the shallow water equations is presented in the paper. The work focuses on the consistency of numerical solution of these equations with the conservation laws of mass and momentum. The investigations involve two different conservative forms which are solved by an implicit box scheme. The theoretical analysis supported by numerical experiments is carried out for rectangular channel...
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New generation of analytical tests based on the assessment of enzymatic and nuclear receptor activity changes induced by environmental pollutants
PublicationAnalytical methods show great potential in biological tests. The analysis of biological response that results from environmental pollutant exposure allows: (i) prediction of the risk of toxic effects and (ii) provision of the background for the development of markers of the toxicants presence. Bioanalytical tests based on changes in enzymatic activity and nuclear receptor action provide extremely high specificity and sensitivity....
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Elastic scattering of electrons by water: An ab initio study
PublicationIn this work we devise a theoretical and computational method to compute the elastic scattering of electrons from a non-spherical potential, such as in the case of molecules and molecular aggregates. Its main feature is represented by the ability of calculating accurate wave functions for continuum states of polycentric systems via the solution of the Lippmann-Schwinger equation, including both the correlation effects and multi-scattering...
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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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Solubility of carbon dioxide in water: Some useful results for hydrate nucleation
PublicationIn this paper, the solubility of carbon dioxide (CO2) in water along the isobar of 400 bar is determined by computer simulations using the well-known TIP4P/Ice force field for water and the TraPPE model for CO2. In particular, the solubility of CO2 in water when in contact with the CO2 liquid phase and the solubility of CO2 in water when in contact with the hydrate have been determined. The solubility of CO2 in a liquid–liquid...
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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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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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Arctic catchment as a sensitive indicator of the environmental changes: distribution and migration of metals (Svalbard)
PublicationArctic regions experience metal pollution, despite their remote location, and the distribution and migration of those metals determine their potential impact on the local environment. Here, a High-Arctic catchment (Revelva, Svalbard) located remotely from human-induced pollution sources is studied with respect to the distribution and migration of chosen trace elements (Ag, Al, As, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Cs, Mo, Ni, Pb,...
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Shallow-Water Acoustic Communications in Strong Multipath Propagation Conditions
PublicationA phenomenon that has a strong impact on signal transmission conditions in Underwater Acoustic Communication (UAC) systems is multipath propagation. As a result of multipath propagation, the transmitted signal undergoes time dispersion which results in inter-symbol interference observed on the receiving side. Time dispersion is large, especially in horizontal channels in shallow waters which significantly limits the transmission...
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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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The importance of the shape of the protein–water interface of a kinesin motor domain for dynamics of the surface atoms of the protein
PublicationA single kinesin motor domain immersed in water has been investigated using molecular dynamics. It has been found that local properties of water in the solvation shell change along with the nature of the neighboring protein surface. However, a detailed analysis leads to the conclusion that the geometrical features of hydrogen bonds and overall structure of kinesin hydration water are not very different from bulk water. The local...
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The importance of the shape of the protein-water interface of a kinesin motor domain for dynamics of the surface atoms of the protein
PublicationSingle kinesin motor domain immersed in water has been investigated using molecular dynamics. It has been found that local properties of water in solvation shell change along with the nature of neighboring protein surface. However, a detailed analysis leads to the conclusion that the geometrical features of hydrogen bonds and overall structure of kinesin hydration water is not very different from bulk water. The local values of...
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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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Reduced-cost surrogate modeling of input characteristics and design optimization of dual-band antennas using response features
PublicationIn this article, a procedure for low-cost surrogate modeling of input characteristics of dual-band antennas has been discussed. The number of training data required for construction of an accurate model has been reduced by representing the antenna reflection response to the level of suitably defined feature points. The points are allocated to capture the critical features of the reflection characteristic, such as the frequencies...
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Calculation of the Effects of Implementing a DSM Electricity Demand Management Strategy Using the Example of Analysis of Changes in the Power System Load
PublicationThe paper presents the impact of implementing Demand Side Management (DSM) solutions through proper management and control of the process of charging and discharging electric car batteries. As a result, the daily load curves were shaped so as to fill valleys and cut down peaks. Therefore, the implementation of power demand management solutions had a significant impact on the power system operation. The impact of DSM solutions manifested...
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ANALYSIS OF IMPACT of SHIP model parameters on changes of control quality index in ship dynamic positioning system
PublicationIn this work there is presented an analysis of impact of ship model parameters on changes of control quality index in a ship dynamic positioning system designed with the use of a backstepping adaptive controller. Assessment of the impact of ship model parameters was performed on the basis of Pareto-Lorentz curves and ABC method in order to determine sets of the parameters which have either crucial, moderate or low impact on objective...
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Monitoring of Chlorine Concentration in Drinking Water Distribution Systems Using an Interval Estimator
PublicationThis paper describes the design of an interval observer for the estimation of unmeasured quality state variables in drinking water distribution systems. The estimator utilizes a set bounded model of uncertainty to produce robust interval bounds on the estimated state variables of the water quality. The bounds are generated by solving two differential equations. Hence the numerical efficiency is sufficient for on-line monitoring...
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Data and knowledge supporting decision-making for the urban Food-Water-Energy nexus
PublicationCities are hubs of innovation and wealth creation, and magnets for an increasing urban population. Cities also face unprecedented challenges in terms of food, water and energy scarcity, and governance and management. Urban environmental issues are no longer problems for experts to address but have become issues of public debate, in which knowledge from multiple sectors is needed to support inclusive governance approaches. Consequently,...
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Non-ergodic fragmentation upon collision-induced activation of cysteine–water cluster cations
PublicationCysteine–water cluster cations Cys(H2O)3,6 + and Cys(H2O)3,6H+ are assembled in He droplets and probed by tandem mass spectrometry with collision-induced activation. Benchmark experimental data for this biologically important system are complemented with theory to elucidate the details of the collisioninduced activation process. Experimental energy thresholds for successive release of water are compared to water dissociation energies...
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Shallow Water Experiment of OFDM Underwater Acoustic Communications
PublicationThe large variability of communication properties of underwater acoustic channels, and especially the strongly varying instantaneous conditions in shallow waters, is a challenge for the designers of underwater acoustic communication (UAC) systems. The use of phase modulated signals does not allow reliable data transmission through such a tough communication channel. However, orthogonal frequency-division multiplexing (OFDM), being...
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Pathogenesis of psoriasis in the “omic” era. Part II. Genetic, genomic and epigenetic changes in psoriasis
PublicationPsoriasis is a multifactorial disease in which genetic, environmental and epigenetic factors regulating gene expression play a key role. In the “genomic era”, genome-wide association studies together with target genotyping platforms performed in different ethnic populations have found more than 50 genetic susceptible markers associated with the risk of psoriasis which have been identified so far. Up till now, the strongest association...
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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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Dynamics of changes in the concentration levels of organic pollutants in the proglacial waters of the Scott River (Spitsbergen, SW Svalbard)
PublicationThe study area covered the NW part of the Wedel Jarlsberg Land. The present study concerns participation of organic pollutants inflow from glacier and seaside plane of Calypsostranda to proglacial waters of the Scott River due to occurrence of precipitation. Concentration ranges for phenols and formaldehyde in water samples are respectively:
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The Influence of Loop Heat Pipe Evaporator Porous Structure Parameters and Charge on Its Effectiveness for Ethanol and Water as Working Fluids
PublicationAbstract: This paper presents the results of experiments carried out on a specially designed experimental rig designed for the study of capillary pressure generated in the Loop Heat Pipe (LHP) evaporator. The commercially available porous structure made of sintered stainless steel constitutes the wick. Three different geometries of the porous wicks were tested, featuring the pore radius of 1, 3 and 7 um. Ethanol and water as two...
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Water Reservoirs as an Element of Shaping Water Resources of Post-Mining Areas
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Physical modelling of water flow in 'Wild River' type water slide
PublicationPrzedstawiono wyniki fizycznego modelowania przepływu w zjeżdżalni wodnej typu Dzika Rzeka. Badania dotyczyły obiektu należącego do parku wodnego "Świat Wodny Nemo" w Sopocie. Eksperymenty przeprowadzono w Laboratorium Hydrauliki i Inżynierii Środowiska Politechniki Gdańskiej. Zaobserwowany w systemie kanałów i zbiorników przepływ wody można ocenić jako szybkozmienny. Wskutek zmian spadku dna kanałów oraz łuków trasy zjazdu obserwowano...
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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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Hydro Lubricants: Water-based lubricants for hydropower applications
PublicationSeveral different base oil types exist in the market including mineral and synthetic oils (e.g. polyalphaolefins, ester, polyglycol, etc.) and are currently widely in use. Although synthetic oils have drawn great attention over the past few decades in terms of their tribological benefits, mineral oils are still widely used in hydropower applications due primarily to their low cost and easy miscibility with other oils. However,...
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Role of the Solvation Water in Remote Interactions of Hyperactive Antifreeze Proteins with the Surface of Ice
PublicationMost protein molecules do not adsorb onto ice, one of the exceptions being so-called antifreeze proteins. In this paper, we describe that there is a force pushing an antifreeze protein molecule away from the ice surface when it is not oriented with its ice-binding plane toward the ice and that this pushing force may be also present even when the protein is oriented with its ice-binding plane toward the ice. This force is absent...
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Microorganisms’ communities from ballast water transferred into the Odra River estuary
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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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Fouling mechanisms in anoxic-aerobic sequencing batch membrane bioreactor based on adapted Hermia models and main foulant characteristics
PublicationVarious derivatives of Hermia models (complete pore blocking, intermediate pore blocking, cake layer formation, and standard pore blocking) and different assessments of foulant characteristics have long been used to determine the membrane fouling mechanisms. Accordingly, this study aims to adapt Hermia models and their combination according to the operating conditions of an anoxic-aerobic sequencing batch membrane bioreactor (A/O-SBMBR)....
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"Creating a numerical model of noise conditions based on the analysis of traffic volume changes in cities with low and medium structure.
PublicationThe subject of this research study is to analyze noise conditions of the selected area in the city of Gdańsk using data related to traffic volume changes during a day. This is because daily distribution of noise levels is much more helpful for noise control and reduction than traditional maps with Lden levels indicated. Calculations are made with the use of a numerical model developed at the Gdansk Univ. of Technology and implemented...
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"Creating a numerical model of noise conditions based on the analysis of traffic volume changes in cities with low and medium structure.
PublicationThe subject of this research study is to analyze noise conditions of the selected area in the city of Gdańsk using data related to traffic volume changes during a day. This is because daily distribution of noise levels is much more helpful for noise control and reduction than traditional maps with Lden levels indicated. Calculations are made with the use of a numerical model developed at the Gdansk Univ. of Technology and implemented...
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Determination of hormones in water samples using liquid chromatography coupled with tandem mass spectrometry
PublicationOver the past few years, many synthetic (ethinylestradiol) and natural (estradiol,estriol, estrone) compounds present in the environment have been affecting the hormonalbalance of humans and animals. Steroid hormones are very often used for medical purposesand have high estrogenic activity what makes them endocrine disrupters. Most hormonalcompounds are released into the water as a result of their incomplete removal in wastewatertreatment...
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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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Providing Public Space Continuities in Post-Industrial Areas through Remodelling Land/Water Connections
PublicationThis article examines the problem of urban transformation strategies applied in recent years which are based on the creation of new water areas and modification of existing ones. The research is an attempt to prove that modifications of plans of water areas and forms of their borders may play an important role in achieving the best quality public spaces in post-industrial territories. The basis for demonstrating the importance...
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Chemical composition of water from roof in Gdańsk, Poland
PublicationThis study deals with the assessment of roof runoff waters from the region of Gdansk collected during the winter season (2007/2008). The chemical analysis includes 16 chemical variables: major ions, PAHs and PCBs measured at 3 sampling sites for 6-14 rain events. Although the data set is of limited volume the statistical data treatment using self-organizing maps (SOM) reveals the main factors controlling roof runoff water quality...
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Modeling changes of the ionospheric potential due to lightning and sprites
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Changes in the Local Government System and Regional Policy in Poland
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Changes of emissions and atmospheric deposition of mercury, lead and cadmium
PublicationPrzedstawiono informacje o zmianach emisji rtęci, ołowiu i kadmu w przeszłości, jak również przedyskutowano poziom aktualnych emisji tych zanieczyszczeń oraz ich scenariusze zmian w przyszłości. Przeanalizowano wpływ różnych parametrów na zmiany emisji w tym stopień implementacji różnych strategii kontroli emisji w Europie. Scenariusze zmian emisji w przyszłości oparte są na scenariuszach rozwoju gospodarczego w poszczególnych...
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Changes in the Use of Agricultural Land in Poland and Czech Republic
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Command in the Police – the concept of changes in the area of formation command
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Lubricity-based estimation of the changes in the brake fluid quality
PublicationW artykule przedstawiono, na podstawie wyników badań laboratoryjnych, możliwość określenia wartości smarności łączącej własności fizykochemiczne i reologiczne płynów. Smarność, która została określona dla trzech płynów hamulcowych (oznaczenia zastrzeżone przez firmę zlecającą porównanie ich własności), umożliwiła wybór najlepszego, który pewnie zostanie zastosowany w instalacjach hamulcowych samochodów.
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Conformational changes of peptidoglycan fragments during their interactions with vancomycin
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High pressure impact on changes in potato starch granules
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Photonic sensor to detect rapid changes in CRP levels
PublicationOne of the most important biomarkers used to determine inflammation is C-reactive protein (CRP). Its level, when it is within the range that does not define inflammation, informs about the risk of cardiovascular events. If the norm is exceeded and inflammation is detected in the body, CRP level can increase 1000 times within a few hours. The type of infection can also be determined based on the level of elevated CRP. All this makes...