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Search results for: DISCHARGE MACHINING
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Silicon oxycarbide-tin nanocomposite derived from a UV crosslinked single source preceramic precursor as high-performance anode materials for Li-ion batteries
PublicationIn this work, we report an innovative and facile UV light-assisted synthesis of a nanocomposite based on silicon oxycarbide (SiOC) and tin nanoparticles. SiOC ceramic matrix, containing a conductive free carbon phase, participates in lithium-ion storage, and buffers the volume changes of Li-alloying/de-alloying material. The reported synthesis procedure through a polymer-derived ceramic route involves the preparation of a single-source...
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Evaluation of the Influence of Farming Practices and Land Use on Groundwater Resources in a Coastal Multi-Aquifer System in Puck Region (Northern Poland)
PublicationThis study focuses on the modeling of groundwater flow and nitrate transport in a multi-aquifer hydrosystem in northern Poland, adjacent to Puck Bay (Baltic sea). The main goal was to investigate how changes in land use and farming practices may affect groundwater recharge and submarine groundwater discharge (SGD) to the sea and the associated N-NO3 fluxes. An integrated modelling approach has been developed, which couples the...
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Engineering Au nanoparticle arrays on SiO2 glass by pulsed UV laser irradiation
PublicationWe study semi-regular arrays of Au nanoparticles (NP) obtained via UV laser irradiation of thin Au films on glass substrate. The NP structures are prepared from films of a thickness up to 60 nm produced by discharge sputtering or pulsed laser deposition, and annealed by nanosecond laser pulses at 266 or 308 nm, respectively, at fluencies in the range of 60-410 mJ/cm2. For the rare- and close-packed NP structures, consistent description...
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Local Structure and Stability of SEI in Graphite and ZFO Electrodes Probed by As K-edge Absorption Spectroscopy
PublicationThe evolution of the solid electrolyte interphase (SEI) during the first Li uptake in advanced Li-ion electrodes is studied by X-ray absorption spectroscopy (XAS). The As atoms present in the electrolyte solution were used as a local probe for monitoring the SEI growth on different electrodes. High-quality As K-edge spectra were collected in fluorescence mode for a set of graphite and carbon-coated ZnFe2O4 electrodes. XAS measurements...
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In-situ odd random phase electrochemical impedance spectroscopy study on the electropolymerization of pyrrole on iron in the presence of sodium salicylate – The influence of the monomer concentration
PublicationIn this work, the potentiostatic electropolymerization of polypyrrole (PPy) on iron in aqueous solution of sodium salicylate and pyrrole is studied in situ by odd random phase electrochemical impedance spectroscopy (ORP-EIS). The influence of the pyrrole concentration on the electrosynthesis process is investigated. The ORP-EIS technique ensures a reliable analysis of the PPy electrosynthesis on iron by means of an advanced data...
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Sources and Fate of PAHs and PCBs in the Marine Environment
PublicationThe assessment of a hazard resulting from the pollution of the environment by chemical compounds is in principle limited to the determination of their concentrations in its various compartments. But for solving many problems in this context, knowledge of the emission sources, transport pathways, and sites of deposition is of great benefit. By far the largest amounts of pollutants, regardless of where they were discharged, end up...
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Eksperymentalna analiza współczynników oporów lokalnych dla wybranych kształtek i złączek w systemach rur wielowarstwowych
PublicationArtykuł poświęcony jest analizie wartości współczynników oporów lokalnych dla wybranych kształtek i złączek pracujących w instalacjach z rur wielowarstwowych z tworzyw sztucznych. Badaniom poddano elementy o średnicach DN16, DN20, DN25, powszechnie wykorzystywane we współczesnych instalacjach sanitarnych. W pracy przedstawiono wybrane wyniki badań laboratoryjnych (dla rozszerzeń, kolanek i trójników) oraz ich porównanie z wartościami...
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Ocena stanu chemicznego i zagrożeń wód podziemnych oraz powierzchniowych w rejonie Zalewu Wślanego
PublicationThe purpose of the research was to examine how factors such as land use and land management affect the quality of groundwater and surface water. These studies were possible thanks to funding from the IDUB Technetium Talent Management Grants project titled “Assessment of Anthropogenic Threat to Groundwater and Surface Water in the Region of the Vistula Lagoon”. The research area included a section of the Vistula Spit, ¯u³awy Wielkie...
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Simulation of fluid structure interaction in a novel design of high pressure axial piston hydraulic pump
PublicationA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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Enhanced supercapacitor materials from pyrolyzed algae and graphene composites
PublicationThis study focuses on the synthesis and characterization of supercapacitor materials derived from pyrolyzed natural compounds. Four compounds were investigated: methylcellulose with lysine (ML), methylcellulose with lysine-graphene composite (MLG), algae (A), and algae-graphene composite (AG). The pyrolysis process was utilized to convert these natural compounds into carbon-based materials suitable for supercapacitor applications....
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Voltage Dependence of Supercapacitor Capacitance
PublicationElectronic Double-Layer Capacitors (EDLC), called Supercapacitors (SC), are electronic devices that are capable to store a relatively high amount of energy in a small volume comparing to other types of capacitors. They are composed of an activated carbon layer and electrolyte solution. The charge is stored on electrodes, forming the Helmholtz layer, and in electrolyte. The capacitance of supercapacitor is voltage- dependent. We...
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Groundwater Quality in the Gdansk Aquifer System
PublicationThe Gdańsk hydrogeological system consists of three main aquifers: Cretaceous, Paleogene-Neogene and Pleistocene. Chemical composition of groundwater varies between water-bearing beds, although water from Pleistocene and Paleogene-Neogene aquifers shows much similarities. The dominant hydrochemical groundwater types is HCO3-Ca. This type is characteristic for Pleistocene deposits in the Kashubian Lake District where natural chemical...
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Simulation of fluid structure interaction in a novel design of high pressure axial piston pump
PublicationA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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Seasonal changes of the concentrations of mineral forms of nitrogen and phosphorus in watercourses in the agricultural catchment area (Bay of Puck, Baltic Sea, Poland)
PublicationThe Baltic Region countries are obliged to meet the stringent limits of N and P discharge set by HELCOM for 2021. Area sources of pollution, including agriculture, are considered the main contributors of biogenic compounds. The Bay of Puck as an inner part of the Baltic Sea is particularly sensitive to eutrophication caused by nutrient in flow from agricultural lands. Rivers and streams inflowing to the Bay of Puck transport nitrogen...
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Hierarchical predictive control of integrated wastewater treatment systems
PublicationThe paper proposes an approach to designing the control structure and algorithms for optimising control of integrated wastewater treatment plant-sewer systems (IWWTS) under a full range of disturbance inputs. The optimised control of IWWTS allows for significant cost savings, fulfilling the effluent discharge limits over a long period and maintaining the system in sustainable operation. Due to the specific features of a wastewater...
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Corrosion Resistance and Surface Bioactivity of Ti6Al4V Alloy after Finish Turning under Ecological Cutting Conditions
PublicationThe influence of cooling conditions and surface topography after finish turning of Ti6Al4V titanium alloy on corrosion resistance and surface bioactivity was analyzed. The samples were machined under dry and minimum quantity lubrication (MQL) conditions to obtain different surface roughness. The surface topographies of the processed samples were assessed and measured using an optical profilometer. The produced samples were subjected...
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Worm Gear Drives with Improved Kinematic Accuracy
PublicationThis paper presents the fundamentals of the design and applications of new worm gear drive solutions, which enable the minimisation of backlash and are characterised by higher kinematic accuracy. Different types of worm surfaces are briefly outlined. Technological problems concerning the principles of achieving a high degree of precision in machining are also described. Special attention is paid to the shaping of conical helical...
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Friction Stir Welding of Aluminum in the Aerospace Industry: The Current Progress and State-of-the-Art Review
PublicationThe use of the friction stir welding (FSW) process as a relatively new solid-state welding technology in the aerospace industry has pushed forward several developments in different related aspects of this strategic industry. In terms of the FSW process itself, due to the geometric limitations involved in the conventional FSW process, many variants have been required over time to suit the different types of geometries and structures,...
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Tool Wear Monitoring Using Improved Dragonfly Optimization Algorithm and Deep Belief Network
PublicationIn recent decades, tool wear monitoring has played a crucial role in the improvement of industrial production quality and efficiency. In the machining process, it is important to predict both tool cost and life, and to reduce the equipment downtime. The conventional methods need enormous quantities of human resources and expert skills to achieve precise tool wear information. To automatically identify the tool wear types, deep...
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Elementary analysis and energetic potential of the sludge from the Gdynia Dębogórze and Lębork wastewater treatment plants
PublicationThe paper aims to show the results of the elementary analysis of the sewage sludges from wastewater treatment plants in Gdynia Dębogórze and Lębork as well as measurements of the heat of combustion and the calculated calorific values according to regulation PN-93/Z-15008, taking into account water content and the composition of sewage sludge at different utilisation stages. The results presented in this paper are based on the analysis...
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BADANIE WPŁYWU INDUKCJI REMANENCJI NA STAN PRZEJŚCIOWY JEDNOFAZOWEGO UKŁADU TRANSFORMATOROWEGO
PublicationW referacie przedstawiono wyniki badań eksperymentalnych i symulacyjnych wpływu indukcji remanencji w rdzeniu transformatora jednofazowego na jego stan przejściowy przy jego pracy jałowej. Badany obiekt jest układem transformatorowym o dwóch uzwojeniach nawiniętych na zwijanym z blachy anizotropowej rdzeniu w kształcie toroidu. Doświadczenia eksperymentalne polegały na rozładowywaniu kondensatora przez uzwojenie strony pierwotnej...
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Investigation on environmental chemistry changes in the Antarctic Special Management Area (ASMA 1): King George Island, South Shetlands Islands
PublicationThe doctoral dissertation included a review of the scientific literature that resulted in the selection of the research area, type of samples and chemical species that were marked. The published series of articles contains an in-depth description of the results of chemical analyses of surface water, sediment and snow samples from the Antarctic Specially Managed Area (ASMA 1) – King George Island. In addition, studies have been...
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Influence of Nitriding and Laser Remelting on Properties of Austenitic Stainless Steel Type X10CrNi18-8 and Cavitation Erosion Resistance
PublicationThe paper presents properties of surface layers. Surface layers were obtained by using low temperature glow–discharge nitriding process and laser remelting carried out on austenitic stainless steel type X10CrNi18-8. Investigations were done by using an Ultra Nanoindentation Tester (UNHT) in the Warsaw Institute of Fundamental Technological Research. The influence of the above mentioned...
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The Impact of Spatiotemporal Changes in Land Development (1984–2019) on the Increase in the Runoff Coefficient in Erbil, Kurdistan Region of Iraq
PublicationNowadays, geospatial techniques are a popular approach for estimating urban flash floods by considering spatiotemporal changes in urban development. In this study, we investigated the impact of Land Use/Land Cover (LULC) changes on the hydrological response of the Erbil basin in the Kurdistan Region of Iraq (KRI). In the studied area, the LULC changes were calculated for 1984, 1994, 2004, 2014 and 2019 using the Digital Elevation...
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A Simplified Method of Trend Removal to Determine Noise Observed During a Supercapacitor’s Discharging
PublicationIn this paper, new method of trend removal is proposed. This is a simplified method based on Empirical Mode Decomposition (EMD). The method was applied for voltage time series observed during supercapacitor discharging process. It assured the determination of an additive noise component after subtracting the identified trend component. We analyzed voltage time series observed between the terminals of the supercapacitor when discharged...
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Low Current Transformer Utilizing Co-Based Amorphous Alloys
PublicationMetal oxide surge arresters have been widely used for protection of power system networks against overvoltages due to atmospheric discharges or malfunction of devices connected to the network. During its operation a surge arrester structure is degradated, what can be observed as an increase of a surge arrester leakage current. Paper presents an implementation of a new, high-permeability, Co64Fe4Ni1Si15B14 amorphous alloy as a current...
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Low current transformer utilizing Co-based amorphous alloys
PublicationMetal oxide surge arresters have been widely used for protection of power system networks against overvoltages due to atmospheric discharges or malfunction of devices connected to the network. During its operation a surge arrester structure is degradated, what can be observed as an increase of a surge arrester leakage current. Paper presents an implementation of a new, high-permeability, Co64Fe4Ni1Si15B14 amorphous alloy as a current...
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Polymer derived SiOC/Sn nanocomposites from a low-cost single source precursor as anode materials for lithium storage applications
PublicationMetal- based materials capable of lithium (Li) alloy formation are key to realization of the next generation of high-energy density anodes for Li-ion batteries, owing to their high storage capacity. Designing a good sup- porting matrix is essential for homogeneously nesting these metallic nanodomains, to effectively utilize their high capacity while tackling the volume expansion issues. Silicon oxycarbides (SiOC), obtained via...
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A New Approach for Investigating the Impact of Pesticides and Nutrient Flux from Agricultural Holdings and Land-Use Structures on Baltic Sea Coastal Waters
PublicationKnowledge related to land-use management impacts on the Baltic Sea ecosystem is limited. The constant release of pollutants into water bodies has resulted in water quality degradation. Therefore, only the innovative approaches integrated with research will provide accurate solutions and methods for proper environment management and will enable understanding and prediction of the impacts of land-use in the Baltic Sea region. Modelling...
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Impact of Urbanization on Stormwater Runoff from a Small Urban Catchment: Gdańsk Małomiejska Basin Case Study
PublicationThis paper deals with the impact of different forms of urbanization on the basin outflow. The influence of changes in land cover/use, drainage system development, reservoirs, and alternative ways of stormwater management (green roofs, permeable pavements) on basin runoff was presented in the case of a small urban basin in Gdańsk (Poland. Seven variants of area development (in the period of 2000-2012) – three historical and four...
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The Influence of Laser Alloying of Ti13Nb13Zr on Surface Topography and Properties
PublicationThe laser alloying is a continually developing surface treatment because of its significant and specific structuration of a surface. In particular, it is applied for Ti alloys, being now the most essential biomaterials` group for load-bearing implants. The present research was performed on the Ti13Nb13Zr alloy subject to laser modification in order to determine the treatment effects on surface topography and its some mechanical...
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Detection and removal of priority substances and emerging pollutants from stormwater: case study of the Kołobrzeska collector, Gdańsk, Poland
PublicationProgressive urban development affects environmental balance and disrupts the hydrologic cycle, in which rainfall plays a significant role. Since rainwater is considered a valuable resource of the environment, many technical solutions are implemented that enable effective rainwater management. On the other hand, stormwater runoff from urban areas contains numerous (also toxic) substances, and therefore should be properly treated....
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Floodsar: Automatic mapping of river flooding extent from multitemporal SAR imagery
PublicationFloodsar is an open-source tool for automatic mapping of the flood extent from a time series of synthetic aperture radar (SAR) imagery. Floodsar is unsupervised, however, it requires defining the parameters search space, geographical area of interest, and some river gauge observations (e.g. water levels or discharges) time series that overlap temporarily with the SAR imagery. Applications of Floodsar are mainly in real-time monitoring...
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Zastosowanie testu biologicznego Microtox do oceny skuteczności działania oczyszczalni ścieków bytowo-przemysłowych
PublicationOcena efektywności procesu oczyszczania ścieków z zastosowaniem biotestu Microtox® na przykładzie wybranej oczyszczalni Powszechnie praktykowanym sposobem wprowadzania ścieków oczyszczonych do środowiska jest ich punktowy zrzut do wód powierzchniowych. Różnorodność działalności prowadzonej w ramach współczesnej gospodarki sprawia, że do oczyszczalni docierają nie tylko substancje, których oznaczanie jest wymagane przez przepisy...
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Improving the Performance of a Graphite Foil/Polyaniline Electrode Material by a Thin PEDOT:PSS Layer for Application in Flexible, High Power Supercapacitors
PublicationIn this study, we present a novel strategy for enhancing polyaniline stability and thus obtaining an electrode material with practical application in supercapacitors. A promising (graphite foil/polyaniline/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) GF/PANI/PEDOT:PSS) electrode material was characterized and used in the construction of a symmetric supercapacitor that provides an outstanding high power density. For this...
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Thermal and Hydrodynamic Phenomena in the Stagnation Zone — Impact of the Inlet Turbulence Characteristics on the Numerical Analyses
PublicationOne of the methods of heat transfer enhancement is utilization of the turbulent impinging jets, which were recently applied, for example, in the heat exchangers. Their positive impact on the heat transfer performance was proven, but many questions related to the origin of this impact are still unanswered. In general, the wall-jet interaction and the near-wall turbulence are supposed to be its main reason, but their accurate numerical...
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Hybrid metal and non-metal activation of Oxone by magnetite nanostructures co-immobilized with nano-carbon black to degrade tetracycline: Fenton and electrochemical enhancement with bio-assay
PublicationElectrochemically synthesized magnetite nanostructures (ESMNPs) as a metal activator and nano-carbon black (NCB) as a non-metal activator were co-immobilized by alginate natural polymer to activate Oxone for the degradation of tetracycline (TC) antibiotic. The formation of sulfate radical was indirectly confirmed during the Oxone/ESMNPs/NCB/alginate process via the addition of scavenging compounds. This study revealed the high...
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Solar light driven degradation of textile dye contaminants for wastewater treatment – studies of novel polycationic selenide photocatalyst and process optimization by response surface methodology desirability factor
PublicationThe unplanned anthropogenic activities and raced industrial revolution detrimentally causes serious threat to terrestrial and aquatic life. A high discharge of wastewater from industries using dyes affects living organisms and the environment. This paper presents studies on polycationic selenides (PCS) synthesized by hydrothermal methods for photocatalytic degradation of dyes. The synthesized PCS were confirmed by various characterization...
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Material Design and Optimisation of Electrochemical Li-Ion Storage Properties of Ternary Silicon Oxycarbide/Graphite/Tin Nanocomposites
PublicationIn this work, we present the characterization and electrochemical performance of various ternary silicon oxycarbide/graphite/tin (SiOC/C/Sn) nanocomposites as anodes for lithium-ion batteries. In binary SiOC/Sn composites, tin nanoparticles may be produced in situ via carbothermal reduction of SnO2 to metallic Sn, which consumes free carbon from the SiOC ceramic phase, thereby limiting the carbon content in the final ceramic nanocomposite....
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Novel strategies to enhance hydrodynamic cavitation in a circular venturi using RANS numerical simulations
PublicationHydrodynamic cavitation is a popular advanced oxidation technique and it has received wide range of applications from waste water treatment to the nanoparticles synthesis in recent years. The enhancement of the intensity of the hydrodynamic cavitation is always been an emerging field of research. Within this framework, we have proposed and investigated three distinct strategies to enhance the intensity of cavitation in a circular...
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Tuning the extraction properties of ionogel-coated Solid-phase microextraction fibers based on the solvation properties of the ionic liquids
PublicationA silica-based network was used to immobilize ionic liquid-based ionogels and applied as a fiber coating forsolid-phase microextraction (SPME). The ionogels were prepared by a sol–gel process, using two ionic liquids,triethylsulfonium bis(trifluoromethylsulfonyl)imide ([Set3][TFSI]) and 1-butyl-1-methylpiperidinium bis(tri-fluoromethylsulfonyl)imide ([C4C1Pip][TFSI]), as well as their equimolar mixture. Methyltrimethoxysilane wasused...
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Silicon oxycarbide ceramics as anodes for lithium ion batteries: influence of carbon content on lithium storage capacity
PublicationWe report here on the synthesis and characterization of silicon oxycarbide (SiOC) in view of its application as a potential anode material for Li-ion batteries. SiOC ceramics are obtained by pyrolysis of various polysiloxanes synthesized by sol–gel methods. The polysiloxanes contain different organic groups attached to silicon, which influence the chemical composition and the microstructure of the final ceramic product. The structure...
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SEI Growth and Depth Profiling on ZFO Electrodes by Soft X-Ray Absorption Spectroscopy
PublicationZnFe2O4 (ZFO) Li-ion batteries (LIBs) represent a reliable, affordable, and safe energy storage technology for use in portable application. However, current LIB active materials (graphite, lithium/transition metal spinel or layered oxides, olivine structures) can store only limited energy since they rely on insertion storage based on solid-state host-guest interactions. Moreover, performances and durability of the cells are strongly...
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Titania nanotubes modified by a pyrolyzed metal-organic framework with zero valent iron centers as a photoanode with enhanced photoelectrochemical, photocatalytical activity and high capacitance
PublicationThe paper discusses the synthesis, photoelectrochemical and electrochemical behaviour of titania nanotube arrays modified by a pyrolyzed metal-organic framework (MOF). A poly(3,4–ethylenedioxyphene) (PEDOT) matrix with an embedded inorganic network of iron hexacyanoferrate (BP) covering TiO2 nanotubes (TNT) is used as a MOF for the further sintering procedure, resulting in a novel, thin film of carbonaceous wrap supported Fe catalytic...
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An application for a new type of pneumatic engine concept
PublicationHeavy trucks are often equipped with loading and unloading systems like dock levellers with swing lip or telescopic lip. Most of these devices require hydro-electrical energy supply systems (eg. the pump that presses the working substance to the actuators must be propelled by electric engine.) The space taken by pump with electric engine can be reduced on condition that a new type of pneumatic drive will be considered. It is possible...
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Analizy ilości i jakości odpływu wód deszczowych i roztopowych z kontrolowanej zlewni zurbanizowanej
PublicationIstotnym problemem Gdańska staje się bezpieczeństwo ekologiczne związane ze spływami miejskimi odprowadzanymi bezpośrednio do wód powierzchniowych, często akwenów użyteczności publicznej. W latach 2011÷2013, Katedra Hydrotechniki Wydziału Inżynierii Lądowej i Środowiska Politechniki Gdańskiej, we współpracy z Wojewódzkim Funduszem Ochrony Środowiska i Gospodarki Wodnej w Gdańsku oraz Gdańskimi Melioracjami, podjęła się wdrożenia...
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Heterotrophic Anodic Denitrification in Microbial Fuel Cells
PublicationNowadays, pollution caused by energy production systems is a major environmental concern. Therefore, the development of sustainable energy sources is required. Amongst others, the microbial fuel cell (MFC) seems to be a possible solution because it can produce clean energy at the same time that waste is stabilized. Unfortunately, mainly due to industrial discharges, the wastes could contain nitrates, or nitrates precursors such...
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Potential Toxic Effects of Airport Runoff Water Samples on the Environment
PublicationDespite the positive aspects of the intensive development of aviation, airports are considered large-scale polluters. Pollution caused by runoff water (stormwater) is one of the major problems related to airport operations. The aim of this study was to characterize the potential toxic impact on aquatic life from runoff water discharges from four international airports in Europe. Samples of stormwater were collected at airports...
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Nitrogen fraction fluctuation during wastewater treatment in a multistage treatment wetland
PublicationAlthough the size of pollutants discharged to a WWTP plays an important and often underestimated role in characterizing treat ability and hence the degree of contaminant removal of wastewater. From one hend In order to obtain efficient nitrogen removal in thedenitrification process, sufficient amounts of bioavailable carbon source should be ensured bur for the other hand in TWs, particulates from the wastewater are naturally trapped...
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Low cost set-up for supercapacitors parameters evaluation
PublicationSupercapacitors are capable to store relatively high amount of energy comparing to its mass. Growing number of these devices applications requires development of new testing methods. Standard methods of evaluation of supercapacitor parameters, as cycling voltammetry, CV, galvanostatic cycling with potential limitation, GCPL, impedance measurements, require equipment of high cost...