Search results for: FREEZE/THAW CYCLE
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Progressing Pollutant Elution from Snowpack and Evolution of its Physicochemical Properties During Melting Period— a Case Study From the Sudetes, Poland
PublicationMain aim of the work assumed recognition of physicochemical changes in snowpack occurring during the melting period. Properties of snow cover had been identified at two sites in Western Sudetes mountains (860 and 1228 m asl) in SW Poland since the end of January, and monitored until the disappearance of snow in late Spring. Snow pit measurements and sample collection at both sites were made followed by chemical analyses with the...
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Mercury intrusion porosimetry (MIP) results of cement pastes containing iron oxide (Fe3O4) nanoparticles (nanomagnetite)
Open Research DataMercury intrusion porosimetry (MIP) data - curves of cement pastes containing iron oxide (Fe3O4) nanoparticles (nanomagnetite) in *.opju (Origin) format.
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Suspended-sediment transport related to ice-cover conditions during cold and warm winters, Toudaoguai stretch of the Yellow River, Inner Mongolia, China
PublicationThe presence of winter ice in cold regions changes the water level, flow rate, velocity distribution, and other parameters of the river, which in turn affects the sediment concentration and channel evolution. Based on data obtained from Toudaoguai Hydrological Station from 1959 to 2021, this study examines the characteristics of the ice regime during cold and warm winters and the water and sediment transport processes along the...
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Katania, 2023, Road SS114 – csv data from sensors on bicycle
Open Research DataData collected with bicycle-mounted sensors on 06.07.2023 while cycling on the cycle path along the SS114 road in Catania. The data includes parameters such as: gps coordinates- txt files, brain waves and heart rate- csv file.
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The TPR reduction profile of MCO powder
Open Research DataThe dataset includes the TPR reduction profiles of MnCo2O4 (MCO) commercial powder. The dataset includes a cycle of reduction under H2/Ar mixture from 100C to 900C. Gas flow:40ml/min and temperature ramp: 10deg/min. Degassed at 200C in He for 1 h.
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Design analysis of ORC micro-turbines making use of thermal energy of oceans
PublicationThe article presents the results of the analysis of energy conversion cycles making use of thermal energy of oceans. The objects of analysis were two cases of closed Organic Rankine Cycle (ORC) power plants, which were: the cycle in which the vapour of the working medium was produced by warm oceanic water in the circum-equatorial zone, and the so-called “arctic” cycle in which this vapour was produced by non-frozen water in the circumpolar...
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Application of the LifeRoSE method in funcionality evaluation of road safety equipment
PublicationThe article presents a mathematical model of the life cycle estimation method of road safety equipment. Then the model was adjusted to estimate the life cycle costs of the chosen horizontal road marking. Using the LCC method, the functionality of the horizontal marking was evaluated in terms of efficiency, durability and economic effectiveness. The article also presents the impact of selected factors on the life cycle costs of...
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Reemission of inorganic pollution from permafrost? A freshwater hydrochemistry study in the lower Kolyma basin (North-East Siberia)
PublicationPermafrost regions are under particular pressure from climate change resulting in widespread landscape changes, which impact also freshwater chemistry. We investi- gated a snapshot of hydrochemistry in various freshwater environments in the lower Kolyma river basin (North-East Siberia, continuous permafrost zone) to explore the mobility of metals, metalloids and non-metals resulting from permafrost thaw. Partic- ular attention...
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Subcritical Thermodynamic Cycles with Organic Medium and Isothermal Expansion
PublicationThe efffciencies of the Organic Rankine Cycle (ORC) are not very high and only very seldom do they exceed 20%. The increase and optimization of initial parameters and certain modifications of the thermodynamic cycle make it possible to overcome these drawbacks. A new modified cycle has been described and analyzed in detail in the paper. Similarly to the Ericsson cycle for gas turbines, isothermal expansion in the turbine is suggested...
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Measurements of power supply system properties of "Magnetic SpeedLine" ultra-fast robot prototype for IML labeling
Open Research DataTests of the power supply system of "SpeedLine magnetic" ultra-fast industrial robot for IML labeling were carried out to analyze the effect of the active power filter (APF) parameters on the power quality. at the target duty cycle. Tests were performed with the target duty cycle. Linear synchronous motors with permanent magnets were used to drive...
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Roofing Materials as Pollution Emiters - Concentration Changes During Runoff
PublicationThe influence of roofing material on concentration of pollutants in roof runoff waters and changes of pollution concentration in time were investigated. In field studies four roofing material types were taken into consideration - ceramic tile, bituminous membrane, asbestos tile and zinc sheeting. Samples were collected since November 2007 to March 2008, anions, cations, metals, PAHs, pesticides and PCB were determined. The existence...
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On Accuracy Modeling of Gas Turbine Cycles by the In-house COM-GAS Code
PublicationIn this paper, a comparison of accuracy modeling of gas turbine cycles between the basic (classical) model and the in-house COM-GAS code has been presented. The basic model uses a semi-perfect gas and well known projecting assumption. On the other hand, the computational flow mechanics (CFM) basis on a real gas by using thermodynamic tables. The thermodynamic analysis of thermal cycles, simply gas cycle GT8C and gas turbine cycle...
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Alternative cogeneration thermodynamic cycles for domestic ORC
PublicationThe Organic Flash Cycle (OFC) is suggested as a vapor power cycle that could potentially improve the efficiency of utilization of the heat source. Low and medium temperature finite thermal sources are considered in the cycle. Additionally the OFC’s aim is to reduce temperature difference during heat addition. The study examines 2 different fluids. Comparisons are drawn between the OFC and an optimized basic Organic Rankine Cycle...
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Assessment of the Environmental Impact of a Car Tire throughout Its Lifecycle Using the LCA Method
PublicationThere are numerous threats to the natural environment that pose a significant risk both to the environment and to human health, including car tires. Thus, there is a need to determine the impact of the life cycle of car tires on the environment, starting with the processes of raw materials acquisition, production, and ending with end-of-life management. Therefore, the authors of this study chose to do research on passenger car...
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Performance of cryogenic oxygen production unit with exhaust gas bleed for sewage sludge gasification and different oxygen purities
PublicationThe paper presents a thermodynamic analysis of the integration of a cryogenic air separation unit into a negative CO2 emission gas power plant. The power cycle utilizes sewage sludge as fuel so this system fits into the innovative idea of bioenergy with carbon capture and storage. A cryogenic air separation unit integrated with the power plant was simulated in professional plant engineering and thermodynamic process analysis software....
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N-doped carbon materials as electrodes for highly stable supercapacitors
PublicationThis article reports a strategy to use nitrogen-doped carbon materials as electrodes for supercapacitors. Depending on the carbon precursor, the porous structure is changed with specific surface area reached up to 2270 m2 g−1. The capacitance of carbon materials used as electrodes is related strictly to pore size. The microstructure and nitrogen functionalities enable a high capacitance (327 F g−1) and cycle durability. The nanoporous...
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Ocena sprawności cyklu roboczego Pojazdu do Usuwania Odpadów z Pojemników na podstawie danych eksploatacyjnych
PublicationW artykule przedstawiona została metoda oceny sprawności cyklu roboczego śmieciarki. Wykorzystując dane eksploatacyjne wyznaczono dwa reprezentatywne cykle i na ich podstawie obliczono zarówno sprawność całego cyklu, jak i jego poszczególnych faz. Porównano wartości energii potrzebnej do opróżniania pojemników, energii do zagęszczania odpadów oraz energii z paliwa. Przedstawiono przebiegi mierzonych i obliczonych wartości w czasie...
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Digital document life cycle development. W: [CD-ROM] Materiały i prezentac-je. Komputeryzacja archiwów polskich muzeów - miejsc pamięci. Konferencja Sztutowo/Kąty Rybackie, 23-24.10.2003. Sztutowo: Państ. Muzeum Stutthof** 2003, 7 s. [14 slajdów] Project IST-2001-33441-MEMORIAL. 5 Program Ramowy UE. Cykliczne życie dokumentu cyfrowego.
PublicationW referacie przedstawiono założenia i cele projektu MEMORIAL UE, jego zada-nia robocze i przebieg prac na jego półmetku. Zaprezentowano w działaniu narzędzie wchodzące w skład pakietu DDW, stanowiące główny produkt realizowane-go projektu.
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From DNA damage to G2 arrest: the many roles of topoisomerase II. W: Prog-ress in Cell Cycle Research. Ed. Meijer L., Jezequel A., Roberge M. London: Plenum Publ. Comp. Ltd**2003 vol. 5 chapt. 30 s. 295-300 Od uszkodzeń DNA do bloku w G2: wiele ról dla topoizomerazy II.
PublicationInhibitory DNA topoizomerazy II sa jednymi z najbardziej szeroko stosowanymi lekami przeciwnowotworowymi. Związki te indukuja pekniecia nici DNA i bloku progresji cyklu komorkowego w fazie G2. Jednak topoizomeraza II jest nie tylko celem molekularnym dla lekow przeciwnowtworowych ale enzym ten pelniwazna role w odpowiedzi komorkowej na dzialanie wielu lekow uszkadzajacych DNA. Topoizomeraza tworzy kompleksy molekularne z bialkami...
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Management of low-temperature heat source by ORC aided by additional heat source
PublicationIn the paper presented is a concept to utilize waste heat from the power plant with the aid of the low-temperature ORC cycle. The ORC system is heated from two heat sources, the first one being the flow rate of waste heat obtained from the exhaust gases. Subsequently, the working fluid in the cycle is additionally heated by the condensing steam from the low pressure turbine extraction points increasing in such way the level of...
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Advanced Turbine Cycles with Organic Media
PublicationOrganic Rankine Cycle (ORC) power plants have become very popular and have found their applications in systems with renewable sources of energy. So far their overall efficiencies are not very impressive and only for the upper temperature of about 300 °C do they exceed 20%. A drawback of these cycles is the limitation of the cycle upper temperature due to the heat exchanger technology and the materials used. However, it is possible...
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Organic Supercritical Thermodynamic Cycles with Isothermal Turbine
PublicationOrganic Rankine cycles (ORC) are quite popular, but the overall efficiencies of these plants are rather very low. Numerous studies have been conducted in many scientific centers and research centers to improve the efficiency of such cycles. The research concerns both the modification of the cycle and the increase in the parameters of the medium at the inlet to the turbine. However, the efficiency of even these modified cycles rarely...
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Spectral Analysis of Capital Markets
PublicationIn this paper the problem of cycles existence in capital markets is addressed. A spectral analysis algorithm, which reduces signal-to-noise ratio, is proposed to derive cycle periodograms for the yield function of DJIA, WIG~20, and NIKKEI 225 indices. Peaks of the the periodograms provide premises to postulate the existence of some possible cycles. The 3.5 year periodicity in all 3 indices, which can be related to Kitchin cycle...
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Anna Kuczyńska-Łażewska dr inż.
PeopleAnna Kuczyńska-Łażewska graduated from the Faculty of Chemistry of the Gdańsk University of Technologyin the field of Chemistry (1st degree) and Environmental Protection Technologies, specialization: environmental protection systems (2nd degree). She completed an internship at the Leibniz-Institut für Katalyse in Rostock. She defended her doctorate in recycling of 1st and 2nd generation modules in 2018 at the Department of Energy...
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Zagospodarowanie ciepła odpadowego z biogazowych agregatów kogeneracyjnych w oczyszczalni ścieków = Waste heat utilisation from cogeneration set in sewage plant
PublicationW pracy opisano koncepcję współpracy biogazowych modułów kogeneracyjnych z niskotemperaturowym obiegiem parowym. Proponowana modernizacja pozwoliłaby na wykorzystanie entalpii fizycznej spalin, tym samym zwiększając sprawność urządzeń wytwarzających ciepło i energię elektryczną. Tego typu rozwiązanie umożliwiłoby częściowe pokrycie zapotrzebowania własnego na energię elektryczną, generując oszczędności w przedsiębiorstwie. W artykule...
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Zagospodarowanie ciepła odpadowego z biogazowych agregatów kogeneracyjnych w oczyszczalni ścieków
PublicationW pracy opisano koncepcję współpracy biogazowych modułów kogeneracyjnych z niskotemperaturowym obiegiem parowym. Proponowana modernizacja pozwoliłaby na wykorzystanie entalpii fizycznej spalin, tym samym zwiększając sprawność urządzeń wytwarzających ciepło i energię elektryczną. Tego typu rozwiązanie umożliwiłoby częściowe pokrycie zapotrzebowania własnego na energię elektryczną, generując oszczędności w przedsiębiorstwie. W artykule...
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Analysis of the selection of low temperature medium for a turbine power plant using ocean thermal energy (OTEC)
PublicationThe paper presents the results and conclusions of numerical calculations modelled in the EES program of a closed OTEC cycle. The following mediums were analysed: ammonia, R32, R41, R404a, R407c, R410a, R423a, R500, R502, R507a and R114, R152a, R234fa, R600, R1234yf, R1234ze. Analogous assumptions were adopted as in the ORC cycle with heat regeneration for dry refrigerants without regeneration for wet refrigerants. Each of them...
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Analysis of the selection of low-temperature medium for a turbine power plant using ocean thermal energy (OTEC)
PublicationThe paper presents the results and conclusions of numerical calculations modelled in the EES program of a closed OTEC cycle. The following mediums were analysed: ammonia, R32, R41, R404a, R407c, R410a, R423a, R500, R502, R507a and R114, R152a, R234fa, R600, R1234yf, R1234ze. Analogous assumptions were adopted as in the ORC cycle with heat regeneration for dry refrigerants without regeneration for wet refrigerants. Each of them...
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Low frequency nois of supecapacitor
Open Research DataDataset contains noise measurement results on prototype electrochemical double layer capacitor. The measurement procedure is described in https://dx.doi.org/10.1515/mms-2017-0059.
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Depth profile of the gold-silver bimetallic structures
Open Research DataSilver and gold bimetallic layers were deposited on a silicon substrate by magnetron sputtering method. Both, Au and Ag layers had 3 nm of thickness. That prepared nanostructures were measured by XPS method. To obtain a depth profile of chemical composition, an Argon ion (Ar+) gun was used for etching surface of sample. Each cycle of etching takes 30...
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Production of certified reference materials - homogeneity and stability study based on the determination of total mercury and methylmercury
PublicationReference materials (RMs) play an important role in all elements of the quality assurance system of measurements. In this work, ``package'' 4 new CRMs (bottom sediment, herring tissue, cod tissue, cormorant tissue) were prepared and characterised to carry out the quality control in monitoring analysis of mercury and methylmercury in environmental samples. Materials - candidates were collected in Poland and south part of the Czech...
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Beta-galactosidase activity of Meiothermus ruber cells
PublicationFreeze-dried cells of Meiothermus ruber catalyses cleavage of o-nitrophenyl-b-D-galactopiranoside (oNPb-gal) and conversion of lactose into glucose and galactose. The permeabilization with 2%toluene,20%ethanol and 20%acetone increased enzymatic activity from 74.87 U/g of lyophilized cells up to 129.44,114.38 and 90.19 U/g,respectively. Ethanol was an effective permeabilizing agent and its efficiency was dependent on the concentration,...
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Anna Rzeczycka dr hab.
PeopleAnna Rzeczycka is the deputy head of the Department of Finance at the Faculty of Economics and Management of the Gdańsk University of Technology. Publications are situated in the field of social sciences in the discipline of economics and finance. They include books, monographs, articles, publications and scientific editions of monographs and scientific journals. In terms of numbers, it includes the following items: 12 monographs...
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Compact High Efficiency and Zero-Emission Gas-Fired Power Plant with Oxy-Combustion and Carbon Capture
PublicationReduction of greenhouse gases emissions is a key challenge for the power generation industry, requiring the implementation of new designs and methods of electricity generation. This article presents a design solution for a novel thermodynamic cycle with two new devices—namely, a wet combustion chamber and a spray-ejector condenser. In the proposed cycle, high temperature occurs in the combustion chamber because of fuel combustion...
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The Influence of Sulfate on Anaerobic Ammonium Oxidation in a Sequencing Batch Reactor
PublicationAnaerobic ammonia-oxidizing bacteria have a more comprehensive metabolism than expected - there may be other electron acceptors that oxidize ammonium nitrogen under anaerobic conditions, in addition to the well-known nitrite nitrogen, one of which is sulfate in the sulfammox process. Sulfate-containing compounds are part of the medium for the anammox process, but their concentrations are not particularly high (0.2 g MgSO4 ∙ 7H2O/dm3...
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Selected aspects of performance of organic Rankine cycles incorporated into bioenergy with carbon capture and storage using gasification of sewage sludge
PublicationThe study aims to investigate the application of the Organic Rankine Cycle (ORC) in the bioenergy with carbon capture and storage (BECCS) using gasification of sewage sludge. The tool used in the investigation is the Aspen Plus software with REFPROP property methods for calculating fluid properties. The reason for this study is that a detailed analysis of the proposed BECCS process flow diagram indicates that a certain amount of...
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The effect of dehydration/rehydration of bacterial nanocellulose on its tensile strength and physicochemical properties
PublicationBacterial nanocellulose (BNC) is a natural biomaterial with a wide range of biomedical applications. BNC contains 99 % of water which makes it too thick to be used as a bioimplant material. The aim of the work was to determine the effect of the BNC dehydration followed by rehydration on its mechanical and physicochemical properties, in the context of the use of BNC as bio-prostheses in the cardiovascular system. Dehydration involved the...
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An influence of molecular weight, deacetylation degree of chitosan xerogels on their antimicrobial activity and cytotoxicity. Comparison of chitosan materials obtained using lactic acid and CO2 saturation.
PublicationThis paper presents a comparison of the antimicrobial activity and cytotoxicity against L929 cells of chitosan xerogels prepared by dissolving the polymer in a solution of lactic acid (LA) or carbonic acid (CO2) and then freeze-drying. There was no simple relationship between the antimicrobial activity and cytotoxicity of the samples obtained using both techniques (LA and CO2). Chitosan materials obtained by the LA method in a...
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Bacterial cellulose vs. bacterial cellulose nanocrystals as stabilizer agents for O/W pickering emulsions
PublicationThe growing interest in Pickering emulsions in functional food systems resulted in the need to find suitable stabilizers for them. The work considers the use of bacterial cellulose for this purpose, and its aim was to compare the properties of disintegrated bacterial cellulose, before and after freeze-drying, and its nanocrystals obtained using H2SO4 under variable of time and concentration conditions. The structure of nanocrystals...
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Cycling performances of the V2O5 nanorods as cathode material in Li-ion batteries
Open Research DataThe DataSet contains the next one hundred galvanostatic charge/discharge curves of the V2O5 nanorods obtained by the sol-gel method. The battery tests of the samples were performed using the Atlas-Sollich 0961 (Atlas-Sollich, Poland) with C/5 and 2C current densities in the voltage range between 2.0 V and 4.0 V vs. Li/Li+. Here 1C is 294 mAh g-1. The...
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Cycling performances of the V2O5 nanocrystals as cathode material in Li-ion batteries
Open Research DataThe DataSet contains the next one hundred galvanostatic charge/discharge curves of the V2O5 nanocrystals obtained by the sol-gel method. The battery tests of the samples were performed using the Atlas-Sollich 0961 (Atlas-Sollich, Poland) with C/5 and 2C current densities in the voltage range between 2.0 V and 4.0 V vs. Li/Li+. Here 1C is 294 mAh g-1. ...
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Depth profile of the chemical composition of the Au-Ag multilayers
Open Research DataSilver and gold multilayers were deposited on a silicon substrate by magnetron sputtering method. Both type, Au and Ag thin films had 2 nm of thickness. Totally structure had thickness of 6 nm (Au-Ag-Au). That prepared multilayers were measured by XPS method. To obtain a depth profile of chemical composition, an Argon ion (Ar+) gun was used for etching...
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Derivation of motor mean phase currents in PMSM drives operating with low switching-to-fundamental frequency ratio
PublicationPulse width modulation (PWM) of inverter output voltage causes the waveforms of motor phase cur-rents to consist of distinctive ripples. In order to provide suitable feedback for the motor current con-trollers, the mean value must be extracted from the currents’ waveforms in every PWM cycle. A com-mon solution to derive the mean phase currents is to sample their value at the midpoint of a symmetrical PWM cycle. Using an assumption...
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Conditions controlling atmospheric pollutant deposition via snowpack
PublicationSolid precipitation represents a potentially important addition to other measures of deposition. However, an accurate estimate of snowfall amount and pollutant loading is not a trivial matter. There are obvious distinctions between regular precipitation collection and snowpack sampling that represent the cumulative chemistry of bulk deposition. The main goal is to show the most important processes and factors that may influence...
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NUMERYCZNY MODEL OBLICZENIOWY OBIEGU TURBINY KLASY 300 MW
PublicationNiniejszy artykuł stanowi opis modelu obiegu cieplnego turbiny o mocy 360MW, utworzonego w preprocesorze numerycznego programu obliczeniowego onazwie DIAGAR. Zadaniem opisywanego modelu jest odtwarzanie zjawisk fizycznych zachodzących w poszczególnych urządzeniach składowych obiegu, zarówno podczas poprawnej (sprawnej) pracy bloku energetycznego, jak i w przypadku pojawienia się niesprawności. Utworzony...
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Ocena kosztu cyklu życia szyn kolejowych w modernizacji układów geometrycznych
PublicationW pracy przedstawiono uwarunkowania historyczne, które doprowadziły do opracowania metod szacowania kosztu życia inwestycji. Opisano podstawowe założenia LCC według modelu przedstawionego w Normach oraz opracowanego w projekcie INNOTRACK. Zaproponowano połączenie powyższych metod i dostosowanie ich do oceny kosztu życia szyn kolejowych w Polce. Przedstawiono elementy wpływające na koszt utrzymania nawierzchni szynowej oraz metody...
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Cycling performances of the V2O5 nanostructures as cathode material in Na-ion batteries
Open Research DataThe DataSet contains the next one hundred galvanostatic charge/discharge curves of the V2O5 nanostructures with different morphology obtained by the sol-gel method. The battery tests of the samples were performed using the Atlas-Sollich 0961 (Atlas-Sollich, Poland) with C/5 current densities in the voltage range between 2.0 V and 4.0 V vs. Li/Li+. Here...
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Feasibility of combined diesel engine - steam turbine in power station operating in the maritime
PublicationCompression-ignition engines used in ship technology as main propulsion engines are large units reaching even to 50-60 MW. Currently, the efficiency of such engines amounts to 45-50%. With such a large power unit, exhaust gases leaving the engine contain very large quantities of heat available for further treatment. Exhaust gases from the piston engine contain about 25% of the heat supplied to the engine in the fuel. Using the...
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Design analysis of combined gas-vapour micro power plant with 30 kW air turbine
PublicationThe article presents basic results of the design analysis of a combined gas-vapour micro power plant with a waste-heat boiler without exhaust reheat, working in the vapour section in the Organic Rankine Cycle (ORC) system. The analysis concerned working media most frequently used in those types of power plants and planned to be used in future. The object of the analysis was a micro power plant with a 30 kW gas (air) turbine for...
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Design analysis of combined gas-vapour micro power plant with 30 kW air turbine
PublicationThe article presents basic results of the design analysis of a combined gas-vapour micro power plant with a waste-heat boiler without exhaust reheat, working in the vapour section in the Organic Rankine Cycle (ORC) system. The analysis concerned working media most frequently used in those types of power plants and planned to be used in future. The object of the analysis was a micro power plant with a 30 kW gas (air) turbine for...