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Search results for: conventional nitrogen removal
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Sustainable investing exchange-traded funds: US and European market
PublicationThe key aim of the paper is to examine the diffusion of the sustainable investing exchange-traded funds (ETFs) on the European and US ETFs markets, with the special focus on the market shares of sustainable investing and conventional funds. The model of diffusion of innovation (logistic growth model) is applied. Monthly data on the assets of ETFs in the time period of 2006-2017 are used. Increasing assets of sustainable investing...
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Właściwości niskotemperaturowe betonów asfaltowych o wysokim module sztywności (AC-WMS) w badaniach trzypunktowego zginania
PublicationArtykuł przedstawia właściwości niskotemperaturowe betonów asfaltowych o wysokim module sztywności. Przedstawione wyniki zostały uzyskane w dwóch badaniach zginania trzypunktowego próbek belkowych: ze stałą prędkością przemieszczenia oraz pod stałym obciążeniem. Obie te metody są od dawna stosowane na Politechnice Gdańskiej do oceny właściwości niskotemperaturowych betonów asfaltowych. Badaniu poddano pięć betonów asfaltowych –...
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Fuel, Oils and Greases, W, E, sem.01, zimowy 22/23
e-Learning CoursesDivision and origin of fuels. Fossil energy resources in Poland and in the world. Production and structure of fuel consumption. Main directions of crude oil processing. Classification and physical properties of gaseous and liquid fuels - natural gas, gasoline, kerosene, diesel oil, heating oil. Classification and characteristic indicators of solid fuels - hard coal, lignite, peat. Fuel contaminants and methods of their removal....
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Sorption of Chlorinated Solvents on Pine and Oak sawdust
PublicationThe article presents assessment of pine and oak sawdusts as sorbents for removal of chlorinated solvents from water. Sawdusts as potential sorbents were characterized with elemental analysis and BET analyses. Sorption capacity was determined for both pine and oak sawdust towards 1,1,2-trichloroethane, tetrachloroethene and 1,1,1,2-tetrachloroethane. Pine sawdust was able to adsorb greater amounts of chlorinated solvents compared...
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Enhancement of PUR/PIR foam thermal stability after addition of Zostera marina biomass component investigated via thermal analysis and isoconversional kinetics
PublicationIn the present work, a thorough thermogravimetric (TG) analysis of bio-based polyurethane–polyisocyanurate (PUR–PIR) foams in both nitrogen and oxygen atmosphere is performed. A sustainable element of the foam is a biopolyol obtained via acid-catalyzed liquefaction of Zostera marina and Enteromorpha Algae biomass. Based on isoconversional analysis and apparent activation energies, several conclusions are obtained. In contradiction...
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Chitosan pyrolysis in the presence of a ZnCl2/NaCl salts for carbons with electrocatalytic activity in oxygen reduction reaction in alkaline solutions
PublicationThe one-step carbonization of low cost and abundant chitosan biopolymer in the presence of salt eutectics ZnCl2/NaCl results in nitrogen-doped carbon nanostructures (8.5 wt.% total nitrogen content). NaCl yields the spacious 3D structure, which allows external oxygen to easily reach the active sites for the oxygen reduction reaction (ORR) distinguished by their high onset potential and the maximum turnover frequency of 0.132 e...
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Investigation of the structural and thermal properties of aluminum-rich Ca–Al–Si–O–N glasses
PublicationIn this paper, we investigate the structure and thermal properties of aluminum-rich transparent Ca–Al–Si–O–N glasses. The obtained glasses were prepared by a traditional melt-quenching technique at 1650 °C using AlN as the nitrogen source. The obtained glasses have a nAl/nSi>1 and contain up to 17 eq.% of N. The structure of the glasses was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, infrared, and Raman...
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Output voltage, current and DC-link voltages under SVPWM, experimental results
Open Research DataThe dataset contains the experimental results of the project: A universal algorithm of space vector pulse width modulation for three-level three and multi-phase NPC inverters with DC-link voltage balancing. The output line-to-line voltage, output current and DC-link voltages were included. The comparison studies between proposed Space Vector Pulse-Width...
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INVESTIGATIONS OF THE EMISSION CHARACTERISTICS OF A DUAL-FUEL GAS TURBINE COMBUSTION CHAMBER OPERATING SIMULTANEOUSLY ON LIQUID AND GASEOUS FUELS
PublicationT his study is dedicated to investigations of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. As the object of the research, a low-emission gas turbine combustion chamber with partial premixing of fuel and air inside the outer and inner radial-axial swirls was chosen. The method of the research is based on the numerical solution of the system of differential...
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The Concept of a Methodology for Selecting the Optimal Parameters of Heat Received from a Nuclear Power Plant Operating in a Partial Cogeneration Mode
PublicationThe paper presents the concept of the objective function which is to allow the selection of optimal parameters of the district heating system using a nuclear power plant operating in partial cogeneration mode. The concept is based on research carried out a number of years ago. The size of annual expenses was proposed as the objective function, which allows to compare the operation of a nuclear power plant in partial cogeneration...
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Electrode-based floating treatment wetlands: Insights into design operation factors influencing bioenergy generation and treatment performance
PublicationExponential increases in energy consumption and wastewater have often irreversible environmental impacts. As a result, bio-electrochemical devices like microbial fuel cells (MFCs), which convert chemical energy in organic matter to electricity using exoelectrogenic bacteria, have gained interest. However, operational factors affecting efficiency and energy output need further study. This research investigated bioenergy production...
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Enhanced sorption of inhibitory compounds from fermentation broth using a MOF@pseudo-DES composite
PublicationThe increase in biorefinery processes underscores the need for effective biofuel generation; nevertheless, inhibitors such as hydroquinone (HQ), 5-hydroxymethylfurfural (HMF), furfural (FF), and vanillin (VAN) resulting from biomass degradation impede microbial growth and process efficiency. Herein, a deep eutectic solvent (DES)-like substance was in-situ generated on the surface of NH2-UiO-66 via a post-synthetic coating process...
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Electrocatalytic performance of oxygen-activated carbon fibre felt anodes mediating degradation mechanism of acetaminophen in aqueous environments
PublicationCarbon felts are flexible and scalable, have high specific areas, and are highly conductive materials that fit the requirements for both anodes and cathodes in advanced electrocatalytic processes. Advanced oxidative modi- fication processes (thermal, chemical, and plasma-chemical) were applied to carbon felt anodes to enhance their efficiency towards electro-oxidation. The modification of the porous anodes results in increased...
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Dariusz Mikielewicz prof. dr hab. inż.
PeopleProfessor Dariusz Mikielewicz – born on February 6, 1967. in Gdansk. Here in 1974 he enrolled first to the Elementary School No. 17, and then in the Grammar School No. 5, named after Stefan Żeromski in Gdansk-Oliwa. After graduating from the Secondary School, with honors, in 1985 he successfully passed the entrance exams to the Faculty of Mechanical Engineering of Technical University of Gdansk, where he graduated with a very good...
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Rating by detection: an artifact detection protocol for rating EEG quality with average event duration
PublicationQuantitative evaluation protocols are critical for the development of algorithms that remove artifacts from real EEG optimally. However, visually inspecting the real EEG to select the top-performing artifact removal pipeline is infeasible while hand-crafted EEG data allow assessing artifact removal configurations only in a simulated environment. This study proposes a novel, principled approach for quantitatively evaluating algorithmically...
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Nutrients, oxygen and suspended matter - Gdansk Deep (2001-2005)
Open Research DataThe results show short-term changes in the concentration of nutrients (nitrates, nitrites, ammonium ions, phosphates and total forms of nitrogen and phosphorus), dissolved oxygen and suspended particulate matter - SPM and its main components (organic carbon - POC, nitrogen - PON, phosphorus - TPP) in the water column of the Gdańsk Deep (Gdańsk Bay).
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Innovative method for utilization of wastewater for security and safety in rural areas
PublicationIn the rural areas building of sewerage systems and central wastewater treatment plants (WWTPs) often brings too high costs, due to high distances from one farm to another and terrain configuration. Individual treatment systems for each farm are a good solution. The teratment wetlands for nine individual farms were constructed in Kaszubian Lake District in summer and autumn 2009. Three configurations of reed beds were chosen. In...
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Fuel, Oils and Greases, W, E, sem.03, zimowy 22/23
e-Learning CoursesDivision and origin of fuels. Fossil energy resources in Poland and in the world. Production and structure of fuel consumption. Main directions of crude oil processing. Classification and physical properties of gaseous and liquid fuels - natural gas, gasoline, kerosene, diesel oil, heating oil. Classification and characteristic indicators of solid fuels - hard coal, lignite, peat. Fuel contaminants and methods of their removal....
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Estimation of Broadband Complex Permeability Using SIW Cavity-Based Multimodal Approach
PublicationIn this article, an attractive multimodal substrate integrated waveguide (SIW) based methodology is presented for the characterization of magnetic materials in the broadband microwave frequency. The proposed approach employs a modified feed under-coupled SIW cavity instead of conventional feed over-coupled multiple SIW cavities; it uses the modified closedform expression, developed from the first principle to consider the effect...
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Graphene oxide thin films deposited on a PCB board - chemical analysis
Open Research DataGraphene oxides based films were measured by X-ray photoemission spectroscopy (XPS) method. TheXPS measurements were carried out with the Omicron NanoTechnology UHV equipment. The hemispherical spectrophotometer was equipped with a 128-channel collector. The XPS measurements were performed at room temperature at a pressure below 1.1 × 10−8 mBar. The...
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Electrochemical oxidation of PFOA and PFOS in landfill leachates at low and highly boron-doped diamond electrodes
PublicationPolyfluorinated alkyl substances (PFASs) may reach landfill leachates (LLs) due to improper waste management. In this study perfluorooctanoate (PFOA) and perfluorooctane sulphonate (PFOS) were used as representatives of PFASs in the decomposition on boron-doped diamond electrodes (BDDs) with high (10k ppm) and low (0.5k ppm) boron doping concentrations. The result shows that although better COD removal efficacies are obtained on...
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Automotive fleet repair facility wastewater treatment using air/ZVI and air/ZVI/H2 O2 processes
PublicationAdvanced automotive fl eet repair facility wastewater treatment was investigated with Zero-Valent Iron/Hydrogen Peroxide (Air/ZVI/H2 O2 ) process for different process parameters: ZVI and H2 O2 doses, time, pH. The highest Chemical Oxygen Demand (COD) removal effi ciency, 76%, was achieved for ZVI/H2 O2 doses 4000/1900 mg/L, 120 min process time, pH 3.0. COD decreased from 933 to 227 mg/L. In optimal process conditions odor and...
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Exposure to cooking emitted volatile organic compounds with recirculating and extracting ventilation solutions
PublicationEnergy-efficient urban development leads to the compact design of apartments. Recirculating ventilation solutions are an attempt to minimize the space required for ventilation ducting, but more data on their performance are needed. Cooking is a major source of volatile organic compounds (VOCs) emissions. It is necessary to assess how well recirculating kitchen hoods perform in reducing the residents' exposure to cooking fumes compared...
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Single-Family Treatment Wetlands Progress in Poland
PublicationLong distances from one farm to another as well as unfavourable terrain configuration in rural areas in Poland result in high investment and operation costs of sewerage systems. Treatment wetlands (TWs) can be an alternative solution to sewage treatment in rural communities, schools, at campsites and for single houses. In this paper the results of 4 years monitoring of single-family treatment plants (SFTWs) in Kaszuby Lake...
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Investigation of ecological parameters of a gas turbine combustion chamber with steam injection for the floating production, storage, and offloading vessel
PublicationThe article is dedicated to the investigation of the possibility of using the contact type gas turbine cycle with steam injection into the combustion chamber for the floating production, storage, and offloading vessel in order to increase the specific power and efficiency and reduce emissions of toxic components. A new approach is proposed, associated with the use of the two-stage injection of superheated steam into a gas turbine...
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Studies on the charge density distribution in p-substituted phenylnitrenium cation
PublicationAniline and its derivatives are known to be mutagenic. This activity is caused by the formation of phenylnitrenium cations during aniline oxidation. Reactivity of the positively charged chemical species can be measured by means of s+ substituent constant. In this paper charge density distribution in p-substituted nitrenium cations and reactivity indices such as, hardness η, electronegativity χ , and electrophilicily ω were analyzed....
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Electrical properties of Na2O-CaO-P2O5 glasses doped with SiO2 and Si3N4
PublicationSodium-calcium-phosphate glasses doped with SiO2 or Si3N4 having similar sodium ion concentrations were prepared by melt quenching. The conductivity was measured by impedance spectroscopy under nitrogen atmosphere in a wide frequency range (10 mHz–1 MHz) and wide temperature range (153–473 K). At 36.6 °C, DC conductivities of all glasses vary between 1.1 ∗ 10−12 and 8.9 ∗ 10−12 S cm−1 and have similar activation energies (between...
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Determination of organophosphorus and organonitrogen pesticides in water samples
PublicationPesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in sources of drinking water, essential to life, is a particular danger. In water, these compounds can undergo transformations, leading to the production of substances of even greater toxicity. Legal regulations are in force, stipulating the highest permissible level of...
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Wetting properties of biosurfactant (rhamnolipid) with synthetic surfactants mixtures in the context of soil remediation
PublicationWetting properties of synthetic surfactant Rokanol NL6, biosurfactant JBR 425 and their mixture have been investigated.The results show that synthetic surfactant addition worsens physicochemical properties of pure biosurfactant but exhibits much higher oil removal efficiency than biosurfactant does.
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Deformations of the steel schell of a vertical cylindrical tank caused by underpressure
PublicationUnderpressure in a tank with a fixed roof may arise in the final stage of its construction as well as during its usage. This article presents stages of deformations of the tank shell and their development from the occurrence of the first deformation to either removal of the causes of underpressure or cracking of the steel shell.
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Właściwości stali S460M napawanej pod wodą metodą lokalnej komory suchej
PublicationW artykule przedstawiono wyniki badań próbek ze stali S460M wykonanych pod wodą metodą lokalnej komory suchej. Pomiary twardości oraz analiza strukturalna wykazały, że dla określonych ilości wprowadzonego ciepła możliwe jest wykonanie złączy bez niezgodności spawalniczych. Stwierdzono formowanie się w pewnych warunkach pęknięć zimnych w SWC wywołanych procesami odprowadzania ciepła z materiału, które są charakterystyczne dla spawania...
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The electrochemical studies for chitosan hydrogel membranes on glassy carbon substrates
Open Research DataThis dataset contains various electrochemical studies carried out to investigate the preconcentration of [Fe(CN)6]3- ions by chitosan hydrogel membranes coating the glassy carbon electrodes. The glassy carbon electrode (GCE, 3.0 mm diameter) was first polished with Al2O3 powder (0.3 mm) using a polishing kit from Buehler, rinsed with deionized...
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Bioaugmentation of a sequencing batch reactor with Archaea for the treatment of reject water
PublicationIn this study, the bioaugmentation of a sequencing batch reactor (SBR) for the treatment of reject water from wastewater treatment plant was evaluated. For the bioaugmentation step a product containing an enrichment of microorganisms from the Archaea domain was used to enhance the performance of the reactor for treating reject water. The experiment was carried out in two parallel lab-scale sequencing batch reactors. The first one...
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The effect of anionic surfactant concentration on activated sludge condition and phosphate release in biological treatment plant
PublicationThis paper discusses the influence of a wide range of anionic surfactant concentrations on activated sludge. Linear alkylbenzene sulphonate (LAS) was chosen as an example of a commonly used anionic surfactant. The fate of the surfactant during biological treatment of wastewater was tested. The effect of surfactant on glucose and starch removal was studied.
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Heat tint colours on stainless steel and welded joints
PublicationSurface layer condition of stainless steels and welded joints influences strongly their corrosion resistance. This problem seems to be underestimated. This current study explains the phenomenon of heat tint forming on welds, the methods of its removal, inspection procedures after heat tint removing and post weld finishing
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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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Preparation and characterization of Pt–N/TiO2 photocatalysts and their efficiency in degradation of recalcitrant chemicals
PublicationSeries of Pt–N/TiO2 photocatalysts were synthesized using the sol–gel method. The photocatalysts’ characteristics by X-ray diffractometry (XRD), scanning transmission electron microscopy (STEM), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) showed that sample with the molar ratio Ti:N equal 1:4 and platinum nanoparticles size of about 3 nm had anatase structure, about 94 m2/g specific surface area...
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The Relationships Between BTEX, NOx, and O3 Concentrations in Urban Air in Gdansk and Gdynia, Poland
PublicationThis paper presents the results of atmospheric air quality research conducted in the areas of two shipyard cities: Gdansk and Gdynia (Poland), in the period between March and December 2011. The purpose of the research was focused on determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds in atmospheric air. Passive sampling technique, with Radiello® diffusive passive samplers, was used for BTEX sample collection...
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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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Urban and road engineering
e-Learning CoursesLectures on Road Engineering cover a wide range of important issues related to the subject, starting from a discussion of the historical circumstances of the creation, development and domination of the contemporary conventional model, through identifying new approaches and standards, emphasizing the importance of universal design, discussing important issues regarding safety and the sense of security, to ways management of greenery,...
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THE USE OF GREEN LOGISTICS ELEMENTS DURING THE CONSTRUCTION OF OFFSHORE VESSELS
PublicationThe article is aimed at the presentation referring to the use of green logistics elements during the construction of the offshore vessels in the following aspects: collection, removal and utilisation of any waste that is harmful for natural environment, elimination of the negative impact that such waste can have on natural environment and the search for the optimal solutions as regards these aspects.
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Electrochemical impedance spectroscopy measurements - conductivity vs. temperature and conductivity vs. oxygen partial pressure - BaCe0.6Zr0.2Y0.1Tb0.1O3-δ
Open Research DataThe dataset consists of two main catalogs consisting of measurement data: of the electrical conductivity of the BaCe0.6Zr0.2Y0.1Tb0.1O3-δ (BCZYTb) sample as a function of temperature and of the electrical conductivity as a function of oxygen partial pressure (pO2). Measurements as a function of temperature were carried out in dry and wet air (pH2O ~...
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Distance measurement by the low coherent interferometer
Open Research DataThe obtained data was acquired by the interferometric fiber-optic sensor of distance. The setup was constructed of a broadband light source working at the central wavelength of 1560 nm, an optical spectrum analyzer and a fiber-optic 2x1 coupler (with the power split 50:50). All elements were connected by standard single-mode optical fibers. The measurement...
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The biotic and abiotic mercury at the coastal zone of Gulf of Gdańsk
Open Research DataConcentration of neurotoxin Hg (mercury) was determined monthly form 01.2012 to 05.2013 (total and suspended) in the surface microlayer and the surface water as well as in: phytoplankton, zooplankton, epilithon, epifithon, phytobenthos (macroalgae and angiosperms), zoobenthos, and in the sediment. The study was conducted in the coastal zone of the Puck...
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On Design Optimization of Miniaturized Microscrip Dual-Band Rat-Race Coupler with Enhanced Bandwidth
PublicationIn the paper, a novel topology of a miniaturized wideband dual-band rat-race coupler has been presented. Small size of the circuit has been obtained by meandering transmission lines of the conventional circuit. At the same time, the number of independent geometry parameters has been increased in order to secure sufficient circuit flexibility in the context of its design optimization for dual-band operation. Optimum dimensions of...
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Performance of acicular grindable thermocouples for temperature measurements at sliding contacts
PublicationThe present study investigates the performance of acicular grindable thermocouples based on a constantan wire / steel hollow cylinder construction. The experiments showed that the measuring junction electrical resistance, temperature–voltage characteristic, measuring junction rise time and signal noise standard deviation of the acicular thermocouples are comparable to those of conventional J-type thermocouples with bare wire diameter...
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Tesla Friction-Type Micro Turbine For Small-Scale Cogeneration
PublicationTesla turbine is rarely used in professional power installations due to its specific work characteristics and relatively low internal efficiency. However, it has some potential to be applied in micro-power plants operating in distributed co-generation systems, also working in an organic Rankine cycle. This paper presents results from numerical calculations of flow in three models of Tesla disk turbines assuming nitrogen as a working...
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A convenient method for the preparation of functionalized N-acylsulfenamides from primary amides.
PublicationWe have developed a convenient method for the synthesis of functionalized N-acylsulfenamides under mild conditions and in moderate to good yields. The designed method is based on the reaction of (5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl)-disulfanyl derivatives with nitrogen nucleophiles generated from primary amides or imides and sodium hydride. The developed method allows for the preparation of N-acylsulfenamides bearing...
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Electrocatalytic Gas Sensor with Reference Layer
PublicationThis paper presents studies of gas sensors prepared in ceramic technology with Nasicon as a solid electrolyte. Sensors work in the voltammetric mode thus based on the excitation of a sensor with a periodic potential signal while current response is recorded. The main aim is to investigate a Bi8Nb2O17 reference layer influence on sensor properties. Sensors I-V characteristics in different concentration of nitrogen dioxide have been...
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UV-Light-Induced Fluctuation Enhanced Sensing by WO3-Based Gas Sensors
PublicationWO3-based gas sensors were investigated under UV-light irradiation and at different working temperatures with the object of achieving superior sensitivity and selectivity. Resistance fluctuations in the WO3 layer were studied together with dc resistance measurements. The data were taken in synthetic air, ethanol, nitrogen dioxide, and mixtures of these gases. We conclude that UV irradiation can easily be applied to enhance the...