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Wyniki wyszukiwania dla: WAVELET PACKET DECOMPOSITION
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Acoustic heating produced in the boundary layer
Publikacja: Instantaneous acoustic heating of a viscous fluid flow in a boundary layer is the subject of investigation. The governing equation of acoustic heating is derived by means of a special linear combination of conservation equations in the differential form, which reduces all acoustic terms in the linear part of the final equation but preserves terms belonging to the thermal mode. The procedure of decomposition is valid in a weakly...
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Solution of the dike-break problem using finite volume method and splitting technique
PublikacjaIn the paper the finite volume method (FVM) is presented for the solution of two-dimensional shallow water equations. These equations are frequently used to simulate the dam-break and dike-break induced flows. The applied numerical algorithm of FVM is based on the wave-propagation algorithm which ensures a stable solution and simultaneously minimizes the numerical errors. The dimensional decomposition according to the coordinate...
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Fast surrogate-assisted simulation-driven design of compact microwave hybrid couplers
PublikacjaThis work presents a robust methodology for expedited simulation-driven design optimization of compact microwave hybrid couplers. The technique relies on problem decomposition, and a bot-tom–up design strategy, starting from the level of basic building blocks of the coupler, and finishing with a tuning procedure that exploits a fast surrogate model of the entire structure. The latter is constructed by cascading local response surface...
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Does offshoring affect industry employment? Evidence from a wide European panel countries
Publikacjais paper contributes to the literature on the possible impact of international outsourcing on domestic labour markets. We focus on off shoring-employment relationship. Th e analysis is performed for a wide European panel, composed of 27 EU countries and 13 manufacturing sectors, observed in the period 1995-2009. Th anks to the use of input-output tables from the WIOD project, we measure the intensity of off shoring in the sectors,...
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Combined chemoresistive and in situ FTIR spectroscopy study of nanoporous NiO films for light-activated nitrogen dioxide and acetone gas sensing
PublikacjaThe chemoresistive sensor response of nanoporous NiO films prepared by advanced gas deposition was investigated by combined resistivity and in situ FTIR spectroscopy, with and without simultaneous light illumination, to detect NO2 and acetone gases. The sensitivity towards NO2 increased dramatically under UV irradiation employing 275 nm light. Improved sensitivity was observed at an elevated temperature of 150 °C. In situ FTIR...
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Pilot study of the influence of thermoplastic starch based polymer packaging material on the growth of diatom population in sea water environment
PublikacjaNovel polymeric packaging materials susceptible to environmentally friendly decomposition appeared on the global market. The paper is devoted to an investigation of the impact of degradable polymer packaging on marine life. The chosen polymer was a commercial packaging based on thermoplastic starch (TPS over 85%). The microorganism chosen was Phaeodactylum tricornutum diatom (identified in many aquatic reservoirs, with a tendency...
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Thermal degradation kinetics of poly(propylene succinate) prepared with the use of natural origin monomers
PublikacjaLinear biobased polyester polyols were prepared with the use of succinic acid and 1,3-pro- panediol (both with natural origin). Tetraisopropyl orthotitanate (TPT) was used as a catalyst. In order to determine the effect of various synthesis temperature conditions on the thermal degradation kinet- ics, nine sequences of temperature conditions were used during two-step polycondensation reaction. Thermogravimetric analysis was conducted...
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Synthesis of Phosphonated Carbon Nanotubes: New Insight into Carbon Nanotubes Functionalization
PublikacjaCarbon nanotubes were successfully functionalized for the first time in a free radical phosphonylation reaction. Three synthetic protocols were proposed. Carbon nanotubes and diethylphosphite reacted in the presence of known radical initiator, such as azobisisobutyronitrile, single electron oxidant—Mn(OAc)3, or under UV radiation. The functionalized material was fully characterized by means of spectroscopic methods, together with...
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Novel cast polyetherurethanes based on dispersed polymeric polyols
PublikacjaOur study was focused on obtaining polyetherurethanes synthesized with using polymeric polyether based polyols differing in dispersed copolymer content (10, 20 and 40 wt%). The polyetherurethane materials were synthesized via two step method. The influence of different polymeric polyether based polyols on the chemical structure, morphology, mechanical and thermal properties of the obtained polyetherurethanes was investigated. The...
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The effect of morphology and crystalline structure of Mo/MoO3 layers on photocatalytic degradation of water organic pollutants
PublikacjaMolybdenum oxide layers were formed by anodization of the Mo metallic foil in a water/ethylene glycol-based electrolyte containing fluoride ions. The as-prepared, amorphous samples were annealed in air at different temperatures in a range from 100 �C to 700 �C. The crystal phase and morphology of anodized and annealed MoO3 layers were investigated using X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The...
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Comparison of bacterial production in the water column between two Arctic fjords, Hornsund and Kongsfjorden (West Spitsbergen)
PublikacjaBacterial production and the accompanying environmental factors were measured in the water columns of two Arctic fjords during the cruise in July and August 2013. Water samples were collected at six stations located in the central part of Hornsund and Kongsfjorden. In Hornsund, where average water temperatures were 1.25-fold lower than in Kongsfjorden, the bacterial production was twice as high (0.116 ± 0.102 vs 0.05 ± 0.03 mg...
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Computationally Effcient Solution of a 2D Diffusive Wave Equation Used for Flood Inundation Problems
PublikacjaThis paper presents a study dealing with increasing the computational efficiency in modeling floodplain inundation using a two-dimensional diffusive wave equation. To this end, the domain decomposition technique was used. The resulting one-dimensional diffusion equations were approximated in space with the modified finite element scheme, whereas time integration was carried out using the implicit two-level scheme. The proposed...
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Mathematical modeling of hydrogen production performance in thermocatalytic reactor based on the intermetallic phase of Ni3Al
PublikacjaThe main goal of the following work is to adjust mathematical modelling for mass transfer, to specific conditions resulting from presence of chemical surface reactions in the flow of the mixture consisting of helium and methanol. The thermocatalytic devices used for decomposition of organic compounds incorporate microchannels coupled at the ends and heated to 500 oC at the walls regions. The results of the experiment were compared...
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Is Germany a Hub of ‘Factory Europe’ for CEE Countries?
PublikacjaThe goal of the paper is to decompose gross exports and imports to/from Germany for seven selected economies in Central and Eastern Europe (CEE): the Czech Republic, Estonia, Hungary, Lithuania, Latvia, Poland and Slovakia for 2000 and 2014, in order to identify the role of Germany in absorbing, reflecting and redirecting CEE trade. The authors use a gross trade decomposition proposed by Bonin and Mancini (2017), which is the extended...
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Techniki zwiększania efektywności metody elementów skończonych poprzez redukcję dziedziny obliczeniowej z wykorzystaniem własności geometrii struktur
PublikacjaWspółczesna elektronika ze względu na swój szybki rozwój wymaga od nas efektywnego modelowania zjawisk polowych. Celem rozprawy jest zwiększanie efektywności metody elementów skończonych poprzez redukcję dziedziny obliczeniowej z wykorzystaniem własności geometrii struktur oraz jej hybrydyzację z użyciem technik analitycznych. Rozprawa zawiera przegląd stanu wiedzy na temat dostępnych obecnie technik modelowania jak również opis...
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Rheological characteristics of oligomeric semiproducts gained via chemical degradation of polyurethane foam using crude glycerin in the presence of different catalysts
PublikacjaPolyurethane (PU) recycling is a topic of growing interest due to the increasing amount of polyurethane waste. The main purpose of polyurethane chemical recycling is to recover the starting polyol. In this study, a method of polyurethane thermochemical recycling, glycerolysis by means of crude glycerin, is proposed. This work presents a comparative study of commercial catalysts used in order to accelerate the decomposition process,...
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The effects of offshoring to low-wage countries on domestic wages: a worldwide industrial analysis
PublikacjaThis paper extends the literature on the implications of offshoring for labour markets by investigating its effect on the wages of different skill groups in a broad global context. The analysis draws on input–output data from the WIOD project, and in the panel analysed (13 manufacturing industries, 40 countries, 1995–2009) we account for up to 96 % of the international trade in manufacturing inputs. Being particularly interested...
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GVC involvement and the gender wage gap: Micro -evidence on European countries
PublikacjaWe examine linkages between involvement in global value chains (GVCs) and gender wage inequalities. We use merged data from Structure of Earnings Survey and the World Input Output Database covering 18 European countries. We employ information on employees’ personal and company characteristics and a sectoral involvement in GVCs. In general, the wages of workers from sectors more involved in GVCs are lower. However, the relationship...
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Organic Vapor Sensing Mechanisms by Large-Area Graphene Back-Gated Field-Effect Transistors under UV Irradiation
PublikacjaThe gas sensing properties of graphene back-gated field-effect transistor (GFET) sensors toward acetonitrile, tetrahydrofuran, and chloroform vapors were investigated with the focus on unfolding possible gas detection mechanisms. The FET configuration of the sensor device enabled gate voltage tuning for enhanced measurements of changes in DC electrical characteristics. Electrical measurements were combined with a fluctuation-enhanced...
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Efficiency of acoustic heating produced in the thermoviscous flow of a fluid with relaxation
PublikacjaInstantaneous acoustic heating of a fluid with thermodynamic relaxation is the subject of investigation. Among others, viscoelastic biological media described by the Maxwell model of the viscous stress tensor, belong to this type of fluid. The governing equation of acoustic heating is derived by means of the special linear combination of conservation equations in differential form, allowing the reduction of all acoustic terms in...
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Reduced model of gyroscopic system
PublikacjaThe paper presents the method of model reduction for the system with gyroscopic interactions. Two methods were used to obtain the approximate discrete models of the continuous structure: the modal decomposition method and the rigid finite element method. The first approach is used for this part of a system for which it is easy to formulate orthogonality conditions, meanwhile the second one is used for other part. The method enables...
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Pressure-induced phase transitions in LnTe (Ln=La, Gd, Ho, Yb) and AmTe
PublikacjaThe structural behaviour under compression of different lanthanide (La, Gd, Ho, Yb) and actinide (Am) monochalcogenides is studied by means of in situ high-pressure x-ray diffraction. All the investigated compounds crystallize at ambient conditions within a cubic (B1) NaCl-type structure but show different behaviours at high pressures. LaTe and AmTe undergo B1 to B2 (CsCl-type structure) phase transitions, starting at 9 GPa and...
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Eurozone or National Inflation Projections: Which has Greater Impact on Consumer Expectations?
PublikacjaWe compare the dependence of consumer inflation expectations on European Central Bank (ECB) inflation projections with that on national central bank (NCB) projections in four economies: Austria, Belgium, Finland, and Germany. We aim to assess whether the information published by central banks affects consumers, and whether inflation projections published by NCBs are more relevant to consumers than those published for the entire...
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Advanced oxidation treatment of Pentoxifylline in aqueous solution
PublikacjaThe degradation of pentoxifylline (PTX) using H2O2, UV, H2O2/UV, Fenton and photo- Fenton processes has been examined in aqueous solution. The influence of various amount of oxidation agent on H2O2, H2O2/UV, Fenton and photo-Fenton reactions were investigated. Initial PTX concentration in Fenton and photo-Fenton was considerated. The addition of inorganic ions (Cl-, NO3-, SO42- and CO32-) on the degradation efficiency of PTX were...
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Acoustic streaming caused by some types of aperiodic sound. Buildup of acoustic streaming
PublikacjaThe analysis of streaming caused by aperiodic sound of different types (switched on at transducer sound or sound determined by initial conditions) is undertaken. The analysis bases on analytical governing equation for streaming Eulerian velocity, which is a result of decomposition of the hydrodynamic equations into acoustic and non-acoustic parts. Its driving force (of acoustic nature) represents a sum of two terms; one is the...
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Nowoczesne metody termochemicznej konwersji biomasy w paliwa gazowe, ciekłe i stałe = Modern methods of thermochemical biomass conversion into gas, liquid and solid fuels
PublikacjaBiomass utilization through direct- or co-combustion with coal, based on coal, hydrogen and oxygen compounds chemical energy conversion into heat in boilers, is simultaneously the cheapest and - according to experts - economically least effective solution. In case of heat and electricity production in cogeneration process in biomass fueled heat and power stations (wood, straw, energetic plants, RDF etc), investment costs are little...
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By-Products from Food Industry as a Promising Alternative for the Conventional Fillers for Wood–Polymer Composites
PublikacjaThe present paper describes the application of two types of food-industry by-products, brewers’ spent grain (BSG), and coffee silverskin (ŁK) as promising alternatives for the conventional beech wood flour (WF) for wood–polymer composites. The main goal was to investigate the impact of partial and complete WF substitution by BSG and ŁK on the processing, structure, physicochemical, mechanical, and thermal properties of resulting...
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The influence of photointercalaction and photochromism effects on the photocatalytic properties of electrochemically obtained maze-like MoO3 microstructures
PublikacjaMolybdenum oxide (α-MoO3) thin films with oriented crystalline facets were synthesised by anodization of Mo foils. The obtained samples were exposed to UV–Vis illumination in aqueous electrolytes providing different cations. The morphology and structure of modified samples were investigated. The effect of photointercalated alkali metal cations (Li+, Na+, K+) on optical and structural properties was studied using UV–vis and Raman...
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Fully bio-based poly(propylene succinate) synthesis and investigation of thermal degradation kinetics with released gases analysis
PublikacjaOne of the most important information about polyesters is their thermal stability and phase transition tem- peratures. These characteristics give information about the promising behavior of the polyester during proces- sing. In this work, linear bio-based polyester polyols were prepared with the use of succinic acid and 1.3- propanediol (both with natural origin). As a polycondensation catalyst was used tetraisopropyl orthotitanate...
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Guessing Intrinsic Forwarding Trustworthiness of Wireless Ad Hoc Network Nodes
PublikacjaA novel node misbehavior detection system called GIFTED is proposed for a multihop wireless ad hoc network (WAHN) whose nodes may selfishly refuse to forward transit packets. The system guesses the nodes’ intrinsic forwarding trustworthiness (IFT) by analyzing end-to-end path performance rather than utilizing unreliable and incentive incompatible low-layer mechanisms. It can work with occasional IFT jumps, directional antennae,...
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Progress in used tyres management in the european union: a review
PublikacjaThe dynamic increase in the manufacture of rubber products, particularly those used in the automobile industry, is responsible for a vast amount of wastes, mostly in the form of used tyres, of which more than 17 million tonnes are produced globally each year. The widely differing chemical compositions and the cross-linked structures of rubber in tyres are the prime reason why they are highly resistant to biodegradation, photochemical...
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Integration and verification of meteorological observations and NWP model data for the local GNSS tomography
PublikacjaGNSS meteorology applies the Global Navigation Satellite Systems (GNSS) to derive information about the state of the atmosphere (particularly troposphere). The tomography is one of the methods used in GNSS meteorology. The input data of GNSS tomography are the signal troposphere delays, results of GNSS data processing and additionally meteorological observations and Numerical Weather Prediction (NWP) models data. Different types...
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Mono- and bimetallic nanoparticles decorated KTaO 3 photocatalysts with improved Vis and UV–Vis light activity
PublikacjaNew mono- and bimetallic nanoparticle-decorated perovskite-type KTaO3 photocatalysts were successfully synthesized by hydrothermal reaction followed by photodeposition of MNPs/BNPs. The effect of noble metal type, amount of metal precursor as well as photoreduction method on the physicochemical and photocatalytic properties of MNPs- and BNPs-KTaO3 have been investigated. Photocatalytic activity under Vis light irradiation was estimated...
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π-Stacking attraction vs. electrostatic repulsion: competing supramolecular interactions in a tpphz-bridged Ru(ii)/Au(iii) complex
PublikacjaThe synthesis and characterization of a mixed metal ruthenium(II)/gold(III) complex bridged by tetrapyridophenazine (tpphz) are described. It is isostructural and isoelectronic to the well-known photocatalysts with palladium(II) or platinum(II). Concentration dependent 1H-NMR spectroscopy and XRD studies show that the electrostatic repulsion between the gold(III) moieties exceeds the attractive π-stacking interaction. Theoretical...
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Softwood-lignin/natural rubber composites containing novel plasticizing agent: Preparation and characterization
PublikacjaComposite materials based on natural rubber were obtained by using glycerolysate (decomposition prod- uct of polyurethane) as a novel plasticizer. In order to determine the effect of various lignin content, four different filler amounts were used, namely, 5 phr (parts per 100 parts of natural rubber) of lignin (WLI5G), 10 phr (WLI10G), 20 phr (WLI20G), and 40 phr (WLI40G). The reference specimen without lignin (WLI0G) was also...
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Magnetic deep eutectic solvents – Fundamentals and applications
PublikacjaMagnetic deep eutectic solvents (MDES), a relatively new subclass of conventional deep eutectic solvents (DES) containing additional paramagnetic components in their structure. MDES exhibit a strong response toward external magnetic fields, thus they can improve many industrial and analytical applications. In addition, this new group of solvents present unique physicochemical properties that can be easily tuned by selecting the...
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Preparation and characterization of Pt/Pd-modified titanium dioxidenanoparticles for visible light irradiation
PublikacjaSeries of Pt/Pd–TiO2photocatalysts were obtained using the sol–gel method. The Pt/Pd–TiO2nanocom-posites showed significant visible light photoactivity. X-ray diffraction, STEM microscopy, UV–visspectroscopy and BET characterization allowed to conclude that the photocatalysts at the best perfor-mance had the anatase structure, 91 m2/g specific surface area, Pt/Pd alloy structure and 1–4 nm particlesize. The photocatalytic activity...
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Quantum privacy witness
PublikacjaWhile it is usually known that the mean value of a single observable is enough to detect entanglement or its distillability, the counterpart of such an approach in the case of quantum privacy has been missing. Here we develop the concept of a privacy witness, i.e., a single observable that may detect the presence of the secure key even in the case of bound entanglement. Then we develop the notion of secret-key estimation based...
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The role of SSVF and SSHF beds in concentrated wastewater treatment, design recommendation
PublikacjaThe return flows of reject water from sewage sludge dewatering alter the activated sludge process ina conventional WWTP and increase TN concentration in the final effluent from WWTP. The objectiveof the investigation carried out was to consider the application of multistage treatment wetland(MTW) for the treatment of reject water from sewage sludge dewatering in a centrifuge (RWC). Thispaper aims to present the design and performance...
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Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction
PublikacjaThis work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties...
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Waste Tyres Pyrolysis for Obtaining Limonene
PublikacjaThis review deals with the technologies of limonene production from waste tyre pyrolysis. Thermal decomposition is attractive for tackling the waste tyre disposal problem, as it enables both: energy to be recovered and limonene to be obtained. This material management recycling of tyres is environmentally more beneficial than the burning of all valuable products, including limonene. Given this recoverability of materials from waste...
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Activation of peroxymonosulfate using carbon black nano-spheres/calcium alginate hydrogel matrix for degradation of acetaminophen: Fe3O4 co-immobilization and microbial community response
PublikacjaHerein, we focused on the degradation of acetaminophen (ACT) drug in liquid phase by peroxymonosulfate (PMS) activated by carbon black nano-spheres (CBNS). The nanostructured activator was immobilized into calcium alginate hydrogel matrix (CAHM) to avoid the washout of the fine nanostructures. The Langmuir modeling showed an insignificant contribution to the adsorption process in the removal of ACT. The basic pH conditions favored...
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A Simplified Method of Trend Removal to Determine Noise Observed During a Supercapacitor’s Discharging
PublikacjaIn 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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Thermal stabilization and permanent deformation resistance of LWA/PCM-modified asphalt road surfaces
PublikacjaThis paper presents the results of attempts at reducing the problem of solar overheating of asphalt road pavement surfaces, resulting in weakening and accelerated destruction of the aforementioned structures. To protect pavement surfaces against periodic overheating, standard asphalt mixture AC 16 W 35/50, used for binder course, has been modified by replacing one of the aggregate fractions from the mineral mixture with lightweight...
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N-doped mesoporous carbon nanosheets obtained by pyrolysis of a chitosan–melamine mixture for the oxygen reduction reaction in alkaline media.
PublikacjaBy simple thermal decomposition of low-cost precursors (chitosan, melamine) in an inert atmosphere, nitrogen-doped porous carbonaceous materials were prepared. The samples pyrolyzed at 700 C are composed of mainly mesoporous nitrogen-doped carbon nanosheets and partially graphitized carbon. The nanosheets contain a disordered area due to the strain imposed by the presence of nitrogen and/or oxygen groups in their structure. Some...
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Energetics of formation and stability in high pressure steam of barium lanthanide cobaltite double perovskites
PublikacjaThis study concerns energetics of formation and the stability in high water partial pressure of BaLnCo2O6−δ, (Ln = La, Pr, Nd, and Gd) (BLnC) and BaGd1−xLaxCo2O6−δ, where x = 0.2, 0.5, and 0.7 (BGLC) double perovskite cobaltites. Those materials are extensively studied due to their potential applications as a positrode in electrochemical devices. Therefore, their stability under such conditions is a key issue. All investigated...
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The role of SSVF and SSHF beds in concentrated wastewater treatment, design recommendation
PublikacjaThe return flows of reject water from sewage sludge dewatering alter the activated sludgeprocess in a conventional WWTP and increas TN concentration in final effluent from WWTPs.The objectives of the investigation carried out is to consider the application of sequential SS VFbeds and an SS HF bed for the treatment of highly polluted wastewater, namely reject waterfrom sewage sludge dewatering in a centrifuge (RWC). This paper aims...
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Synthesis and thermal studies of flexible polyurethane nanocomposite foams obtained using nanoclay modified with flame retardant compound
PublikacjaThis work presents thermal studies of nanocomposites based on the flexible polyurethane (PU) matrix and filled using montmorillonite organically modified with organophosphorus flame retardant compound. Flexible PU nanocomposite foams were prepared in the reaction carried out between reactive alcoholic hydroxyl and isocyanate groups with the ratio of NCO to OH groups equal to 1.05. The amount of an organoclay ranging from 3 to 9...
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Cost-Efficient Design Methodology for Compact Rat-Race Couplers
PublikacjaIn this article, a reliable and low-cost design methodology for simulation-driven optimization of miniaturized rat-race couplers (RRCs) is presented. We exploit a two-stage design approach, where a composite structure (a basic building block of the RRC structure) is first optimized using a pattern search algorithm, and, subsequently, the entire coupler is tuned by means of surrogate-based optimization (SBO) procedure. SBO is executed...
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Theoretical studies of fragmentation processes of neutral and ionized furan molecule
PublikacjaThis PhD thesis focuses on the fragmentation mechanism of the furan molecule in the gas phase. The approach taken in this work comprised of three theoretical methodologies considering the dynamical, energetical and entropic aspects of the studied process. First, molecular dynamics simulations were performed. Next, the potential energy surfaces were explored at the DFT/B3LYP level of theory. Finally, a new statistical Microcanonical...