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Wyniki wyszukiwania dla: biogas reforming ceria transition metal reaction quotient
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Structural and catalytic properties of ceria layers doped with transition metals for SOFCs fueled by biogas
PublikacjaThe aim of this paper was to investigate an influence of the nanocrystalline Ce0.8A0.2O2-δ (A = Mn, Fe, Co, Ni, Cu) materials on the direct internal reforming of biogas in SOFC. Structural analysis of fabricated compounds has been done. An in-situ analysis of a composition of outlet gases from operating SOFC was performed using FTIR spectroscopy with simultaneous electrical tests. It was found out, that type of dopant strongly...
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Copper and cobalt co-doped ceria as an anode catalyst for DIR-SOFCs fueled by biogas
PublikacjaThe nanocrystalline compounds of Co and Cu co-doped ceria (with up to 20 mol.% of dopants) were fabricated by the reverse microemulsion synthesis method. They were deposited in a form of layers on the surface of SOFC anode in an aim to act as electrochemically active materials for biogas reforming process. Fourier Transformed Infrared Spectroscopy was used to analyze a composition of outlet gases simultaneously with the tests of...
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Investigation of praseodymium and samarium co-doped ceria as an anode catalyst for DIR-SOFC fueled by biogas
PublikacjaThe Pr and Sm co-doped ceria (with up to 20 mol.% of dopants) compounds were examined as catalytic layers on the surface of SOFC anode directly fed by biogas to increase a lifetime and the efficiency of commercially available DIR-SOFC without the usage of an external reformer. The XRD, SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore, the electrical...
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Investigation of functional layers of solid oxide fuel cell anodes for synthetic biogas reforming
PublikacjaSolid oxide fuel cells (SOFCs) are one of the most promising energy conversion devices due to their high efficiency, low pollution and fuel flexibility. Unfortunately, when hydrocarbons are used as a fuel, for example in the form of a biogas, solid carbon can deposit on the anode surface. This process leads to the degradation of the fuel cell performance. A possible solution to this problem is to apply an additional catalytic material,...
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CeCu2O4 as a functional layer on solid oxide fuel cells for synthetic biogas reforming
PublikacjaSolid Oxide Fuel Cells (SOFC) are one of the most promising electrochemical devices, which can convert chemical energy to the electrical energy these days. Their ability to work with different kind of fuel makes them noteworthy. SOFC can work with biogas. The problem arises when solid carbon starts to be deposited in anode. That leads to degradation of fuel cell. Simple solution is to apply catalytic functional layer, which is...
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Catalytic activity of Ni-MgAl2O4 modified with transition metal (Ti, Mo, W) carbides as potential catalysts for resource recovery via dry reforming of waste plastics
PublikacjaThe growing amounts of plastic waste and CO2 emissions are two environmental threats that require urgent attention. Pyrolysis combined with dry reforming (PCDR) is a technology that allows both CO2 utilization and resource recovery from waste plastic. New catalysts for PCDR are crucial for developing efficient and stable processes that can be widely implemented in the industry. In this study, Ni/MgAl2O4 catalysts modified using different...
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Metal (Mo, W, Ti) Carbide Catalysts: Synthesis and Application as Alternative Catalysts for Dry Reforming of Hydrocarbons—A Review
PublikacjaDry reforming of hydrocarbons (DRH) is a pro-environmental method for syngas production. It owes its pro-environmental character to the use of carbon dioxide, which is one of the main greenhouse gases. Currently used nickel catalysts on oxide supports suffer from rapid deactivation due to sintering of active metal particles or the deposition of carbon deposits blocking the flow of gases through the reaction tube. In this view,...
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Nanostructure of the laser-modified transition metal nanocomposites for water splitting
PublikacjaAlthough hydrogen is considered by many to be the green fuel of the future, nowadays it is primarily produced through steam reforming, which is a process far from ecological. Therefore, emphasis is being put on the development of electrodes capable of the efficient production of hydrogen and oxygen from water. To make the green alternative possible, the solution should be cost-efficient and well processable, generating less waste...
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Calixthioamides as ionophores for transition and heavy-metal cations
PublikacjaThere is an increasing interest in applying p-tert-butylcalix[4]arenes as sensing materials in ion-selective electrodes(ISEs). Considerable efforts were made to design calixarenes that are selective for some heavy- or transitionmetal ions to be used in ISEs for controlling and monitoring the level of such pollutants in the environment. It has been reported that introduction of softer sulfur atoms instead of oxygen atoms in calix[4]arene...
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Calix[4]arene-Thioamides as Ionophores for Transition and Heavy Metal cations
PublikacjaCalix[4]arene derivatives play an important role as sensing materials in Ion Selective Electrodes(ISEs). Nowadays a high impact is put to control in natural waters the level of toxic heavy metals, like Pb ,Cd, Hg or Cu which may cause the great risk to human health. Our goal was to design and to synthesize ligands possessing ability to bind transition and heavy metal cations. The synthesis, crystal structures,extractive and ionophoric...
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Transition Metal Oxides influence on phosphate and borate glasses structure
PublikacjaBorate and phosphate glasses possess many potential luminescence and optical applications. With their low melting point, they are one of the most often studied amorphous materials. In recent years these glasses, doped with transition metal oxides (TMO), gained much attention due to their tunable structural and thermal properties. Review of systems containing TMOs was presented. Additionally synthesis of binary MnO-P2O5 and MnO-B2O3...
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Insulator to correlated metal transition in V1−xMoxO2
PublikacjaDyskutowane jest przejście typu izolatro - metal w domieszkowanym atomami Molibdenu związku V1-xMoxO2. Prezentowany jest diagram fazowy.
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Insulator to correlated metal transition inV1−xMoxO2
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The role of aluminium in metal–organic frameworks derived carbon doped with cobalt in electrocatalytic oxygen evolution reaction
PublikacjaWater electrolysis is one of the most crucial processes in the development of new energy sources, where ultra-clean fuel is produced - hydrogen. Oxygen evolution reaction (OER) is the sluggish process of overall water splitting. Therefore, this study presents the design, characterization and electrochemical study of cobalt-based electrocatalysts embedded into porous carbons derived from an Al-metal–organic...
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Syntheses and Structures of Transition Metal Complexes with Phosphanylphosphinidene Chalcogenide Ligands
PublikacjaThe reactivity of the phosphanylphosphinidene complex [(DippN)2W(Cl)(η2-P-PtBu2)]− (1) toward chalcogens (Ch = Se, S) was studied. Reactions of stoichiometric amounts of 1 with chalcogens in DME yielded monomeric tungsten complexes with phosphanylphosphinidene chalcogenide ligands of the formula tBu2P−P−Ch (Ch = Se (in 2) and S (in 5)), which can be regarded as products of the addition of a chalcogen atom to a P=W bond in starting...
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Preparation of methanation catalysts for high temperature SOEC by β-cyclodextrin-assisted impregnation of nano-CeO2 with transition metal oxides
PublikacjaThe aim of this work was to prepare and examine the catalytic activity of nanometric CeO2 decorated with transition metal oxides – Ni, Co, Cu, Fe and Mn – towards a high-temperature methanation process under SOEC CO2/H2O simulated co-electrolysis conditions. Samples were prepared using the wet impregnation method via the conventional process and with the addition of native cyclodextrin. The influence of β-cyclodextrin (βCD) onto...
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Thermodynamic Properties of Inorganic Salts in Nonaqueous Solvents. VI. Apparent Molar Volumes, Expansibilities, and Compressibilities of Divalent Transition Metal Ions in Methanol and Dimethylsulfoxide
PublikacjaThe temperature dependence of the density of divalent transition metal perchlorates in dimethylsulfoxide as well as cobalt(II), nickel(II) perchlorates, and copper(II) trifluoromethanesulfonate in methanol was determined. Moreover, sound velocities for solutions of cobalt(II), nickel(II) perchlorates, and copper(II) trifluoromethanesulfonate in methanol have been measured at 298.15 K. From these data, the partial molar volumes,...
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Study of ZrS3-based field-effect transistors toward the understanding of the mechanisms of light-enhanced gas sensing by transition metal trichalcogenides
PublikacjaExtending knowledge of the properties of low-dimensional van der Waals materials, including their reactivity to the ambiance, is important for developing innovative electronic and optoelectronic devices. Transition metal trichalcogenides with tunable optical band gaps and anisotropic conductivity are an emerging class among low- dimensional structures with the possibility of gate tunability and photoreactivity. These properties...
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Application of Coordination Compounds with Transition Metal Ions in the Chemical Industry—A Review
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Calix[4]arene-Thioamides as Ionophores for Transition and Heavy Metal Cations.
PublikacjaPochodne kaliks[4]arenów odgrywają ważną rolę jako materiał aktywny w membranowych elektrodach jonoselektywnych. Obecnie duży nacisk kładzie się na kontrolę stężeń kationów metali ciężkich, takich jak Pb, Cd, Hg, Cu w wodach naturalnych. Naszym zadaniem było zaprojektować i zsyntezować ligandy, które wykazują zdolność do wiązania kationów metali ciężkich i przejściowych. Synteza, struktury krystaliczne, ekstrakcja i właściwości...
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Identification of multisite behavior in a broadly emitting transition-metal system using pressure
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Apparent molar volumes of divalent transition metal bromides in dimethyl sulfoxide solutions
PublikacjaWyznaczono pozorne i cząstkowe molowe objętości bromków dwuwartościowych metali przejściowych szeregu Mn(II)-Zn(II)w roztworach w dimetylosulfotlenku. Przedyskutowano korelacje między objętościami molowymi a stanami koordynacyjnymi i sposobem jonizacji soli.
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Transition-Metal-Promoted Oxidative Cyclization To Give 1,2,4-Trisubstituted Carbazole Scaffolds
PublikacjaHerein, we describe the synthesis of a 1,2,4-trisubstituted carbazole core from 5-(1H-indol-3-yl)-3-oxopentanoic acid esters or amides. For oxidative cyclization, we tested two different approaches. First, we used manganese triacetate as a conventional moderate oxidizer to ensure the radical course of the reaction. Second, we examined the use of a more complex oxidizing agent I2/Me(OTf)3. In both cases, formation of a fused-ring...
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Group-9 Transition-Metal Suboxides Adopting the Filled-Ti2Ni Structure: A Class of Superconductors Exhibiting Exceptionally High Upper Critical Fields
PublikacjaTi2Ni and the related η-carbide structure are known to exhibit various intriguing physical properties. The Ti2Ni structure with the cubic space group Fd3̅m is surprisingly complex, consisting of a unit cell with 96 metal atoms. The related η-carbide compounds correspond to a filled version of the Ti2Ni structure. Here, we report on the structure and superconductivity in the η-carbide-type suboxides Ti4M2O with M = Co, Rh, and Ir....
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Functionalization of the transition metal oxides FeO, CoO, and NiO with alkali metal atoms decreases their ionization potentials by 3–5 eV
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Adiabatic Compressibilities of Divalent Transition-Metal Perchlorates and Chlorides in N,N-Dimethylacetamide and Dimethylsulfoxide
PublikacjaZmierzono prędkości rozchodzenia się dźwięku roztworów nadchloranów i chlorków manganu(II), kobaltu(II), niklu(II), miedzi(II) i cynku(II) w N,N-dimetyloacetamidzie i dimetylosulfotlenku w temperaturze 298.15 K. Obliczono ściśliwości adiabatyczne i pozorne ściśliwości adiabatyczne badanych roztworów. Przedyskutowano wpływ anionu i rodzaju rozpuszczalnika na uzyskane graniczne wartości pozornych ściśliwości adiabatycznych soli.
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Apparent molar volumes of divalent transition metal chlorides and perchlorates in dimethyl sulfoxide solutions.
PublikacjaZmierzono gęstości roztworów nadchloranów i chlorków dwuwartościowych metali szeregu Mn(II)-Zn(II) w dimetylosulfotenku. Wyznaczone na drodze ekstrapolacji cząstkowe objętości molowe nadchloranów rozdzielono na udziały jonowe. Przeanalizowano wpływ pola ligandów na cząstkowe objętości molowe kationów. Przedstawiono związek między wartościami pozornych objętości molowych a stanami koordynacyjnymi soli w DMSO.
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Apparent molar volumes of divalent transition metal perchlorates and chlorides in N,N-dimethylacetamide.
PublikacjaZmierzono gęstości roztworów nadchloranów i chlorków manganu(II), kobaltu(II), niklu(II), miedzi(II) i cynku(II) w temperaturach 10, 20,25, 30, 40, 50 i 60(o)C. Obliczono pozorne objętości molowe. Wyznaczono graniczne wartości cząstkowych molowych objętości tych soli oraz odpowiednie rozszerzalności. Przeanalizowano i wyjaśniono różnice we właściwościach wolumetrycznych roztworów nadchloranów i chlorków.
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Chemical-vapor generation of transition metals through the reaction with tetrahydroborate in recent achievements in analytical atomic spectrometry
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Mixed electronic-ionic conductivity in transition metal oxide glasses con-taining alkaline ions
PublikacjaOpisano właściwości elektryczne szkieł z tlenkami metali przejściowych zawierających jony metali alkalicznych. Szczególną uwagę zwrócono na typowe zmiany przewodnictwa występujące przy domieszkowaniu tego typu szkieł jonami metali alkalicznych. Porównano przewodnictwo elektryczne szkieł fosforanowo-żelazowych zawierających jony sodu z przewodnictwem szkieł bizmutowo-miedziowych.
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Overview of the Synthesis and Catalytic Reactivity of Transition Metal Complexes Based on C═P Bond Systems
PublikacjaThis report provides an overview of the use of phosphaalkenes (C=P) in syntheses of various complexes. Going through successive complexes containing the d-block metals, we sought how this area of chemistry was formed over the years. Additionally, this work contains information on the possible coordination types and means of constructing the complexes. In addition, this review reveals the reactivities of phosphaalkene complexes...
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Solvation and partial molar volumes of some transition metal cations in N,N-dimethylacetamide, triethylphosphate and acetonitrile.
PublikacjaW oparciu o precyzyjne pomiary gęstości roztworów nadchloranów metali przejściowych szeregu Mn(II)-Zn(II) w DMA, TEP i AN wyznaczono pozorne molowe oraz graniczne wartości cząstkowych molowych objętości sole w temperaturach 293, 298 i 303,15 K. Wyznaczone wartości rozdzielono na udziały jonowe. Przeanalizowano czynniki decydujące o wielkości cząstkowych molowych objętości solwatowanych kationów.
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O-substituted tetrahydroxamate derivatives of p-tert-butylcalix[4]arene as receptors for transition and heavy metal cations
PublikacjaTetrasubstituted O-hydroxamate derivatives of p-tert-butylcalix[4]arene were applied as active materials in ion-selective membrane electrodes and were tested towards Pb-selectivity. The electrodes gave near-Nernstian characteristics for Pb2+ cations. The selectivity coefficients were determined. The influence of plasticizer on the electrode behaviour was studied. The dependence of the chemical structure on selectivity coefficients...
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Interaction of Ionomers and Polyelectrolytes with Divalent Transition Metal Cations (Cu2+ and VO2+): A Study by Electron Spin Resonance (ESR) Spectroscopy and Viscosimetry
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Achiral and Chiral Transition Metal Complexes with Modularly Designed Tridentate PNP Pincer-Type Ligands Based on N-Heterocyclic Diamines
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Thermodynamic properties of inorganic salts in nonaqueous solvents. II. Apparent molar volumes and compressibilities of divalent transition-metal perchlorates in acetonitrile
PublikacjaW oparciu w wyniki pomiarów gęstości wykonanych w temperaturze 15,20,25,30,35,40 i 50 stopni Celsjusza oraz pomiaru szybkości dżwięku w temperaturze 25 stopni Celsjusza, wyznaczono pozorne objętości molowe oraz ściśliwości adiabatyczne roztworów nadchloranów manganu(II), kobaltu(II), niklu(II) i cynku(II). Obliczono odpowiednie wartości standardowe oraz rozszerzalności izobaryczne. Przeanalizowano związki między strukurą elektronową...
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Thermodynamic properties of inorganic salt in nonaqeous solvents. IV. Apparent molar volumes and compressibilities of divalent transition-metal bromides and chlorides in acetonitrile
PublikacjaWykonano pomiary gęstości roztworów chlorków i bromków w acetonitrylu w temperaturze 288.15, 293.15, 298.15, 303.15, 308.15, 313.15 K oraz pomiar szybkości rozchodzenia się dźwięku w badanych roztworach w temperaturze 298.15 K. Uzyskane wartości pozwoliły wyznaczyć pozorne objętości molowe oraz pozorne adiabatyczne ściśliwości, których wartości oraz zmiany ze stężeniem tłumaczone są obecnością złożonych układów komplesów w roztworze.
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Thermodynamic properties of inorganic salts in nonaqueous solvents. III. Apparent molar volumes and compressibilities of divalent transition-metal chlorides in N,N-dimethylformamide
PublikacjaZmierzono gęstości i szybkości dźwięku dla roztworów chlorków dwuwartościowych metali przejściowych w N,N-dimetyloformamidzie. W oparciu o uzyskane wyniki wyznaczono pozorne objętości molowe, cząstkowe objętości molowe, rozszerzalności izobaryczne oraz ściśliwości adiabatyczne. Dokonano analizy oraz zbadano wpływ kompleksowania na wyznaczone wielkości.
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Thermodynamic properties of inorganic salts in nonaqueous solvents. V. Apparent molar volumes and compressibilities of divalent transition metal bromides in N,N-dimethylformamide
PublikacjaZmierzono gęstości i szybkości rozchodzenia się dźwięku roztworów bromków dwuwartościowych metali przejściowych w N,N-dimetyloformamidzie. W oparciu o uzyskane parametry wyznaczono pozorne objętości i ściśliwości molowe. Dokonano analizy oraz zbadano wpływ kompleksowania na wyznaczone wielkości.
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Thermodynamic properties of inorganic salts in nonaqueous solvents. I. Apparent molar volumes and compressibilities of divalent transition-metal perchlorates in N,N-dimethylformamide.
PublikacjaZmierzono gęstości i szybkość dźwięku dla roztworów nadchloranów dwuwartościowych metali przejściowych w N,N-dimetyloformamidzie. W oparciu o uzyskane wyniki wyznaczono pozorne objętości molowe, cząstkowe objętości molowe, rozszerzalności izobaryczne oraz ściśliwości adiabatyczne. Dokonano analizy oraz zbadano wpływ rodzaju kationu metalu.
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The influence of synthesis method on the microstructure and catalytic performance of Y 0.07 Sr 0.93 Ti 0.8 Fe 0.2 O 3-δ in synthetic biogas operated solid oxide fuel cells
PublikacjaThe Y0.07Sr0.93Ti0.8Fe0.2O3-δ (YSTF) material was fabricated using three different synthesis methods: modified polymer precursor method (MPP), Pechini method and a solid state reaction method. It was applied as an anode catalytic material for biogas reforming in solid oxide fuel cells. Clear differences in the microstructure of fabricated catalytic layers were found, mainly with respect to a grain size and distribution of grains....
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Branched Poly(l-lysine)-Derived Nitrogen-Containing Porous Carbon Flake as the Metal-Free Electrocatalyst toward Efficient Oxygen Reduction Reaction
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Catalytic Activity of Nickel and Ruthenium–Nickel Catalysts Supported on SiO2, ZrO2, Al2O3, and MgAl2O4 in a Dry Reforming Process
PublikacjaDry reforming of methane (DRM) is an eco-friendly method of syngas production due to the utilization of two main greenhouse gases—methane and carbon dioxide. An industrial application of methane dry reforming requires the use of a catalyst with high activity, stability over a long time, and the ability to catalyze a reaction, leading to the needed a hydrogen/carbon monoxide ratio. Thus, the aim of the study was to investigate the...
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Synthesis, spectroscopy and crystal structure determination of heteroleptic cobalt(II) silanethiolates with pyridine derivatives
PublikacjaCztery nowe tri-tert-butoksysilanotiolanowe kompleksy kobaltu(II) z 3- i 4-metylopirydyną zostały zsyntetyzowane i scharakteryzowane. Monometaliczne kompleksy otrzymano w reakcji bimetalicznego kompleksu [Co(SSi(OtBu)3(NH3)]2, który posłużył jako substrat kobaltu(II). Nowe związki zostały scharakteryzowane przy użyciu rentgenografii strukturalnej oraz spektroskopii UV-vis i FT-IR, a także za pomocą analizy elementarnej. Kompleksy...
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Chiral Schiff base complexes as an effective catalyst in Diels-Alder reaction
PublikacjaDiels Alder reaction is a very important tool in carbon-carbon bond formation. It is a cycloaddition between a conjugated diene and a second compound called dienophile. Where one or more heteroatoms are present in the diene and/or dienophile framework, the cycloaddition is called hetero-Diels-Alder reaction (HDA). The asymmetric Diels-Alder reaction is among the most powerful available methodologies for that construction of optically...
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Investigation of catalytic layers on anode for solid oxide fuel cells operating with synthetic biogas
PublikacjaIn this paper solid oxide fuel cells operating with dry synthetic biogas have been examined. In order to increase their stability the layers of CuO-CeO2, Cu1.3Mn1.7O4 and Y0.08Sr0.92Ti0.8Fe0.2O3 -δ have been deposited on the Ni-YSZ anode site. These layers should catalyze the internal biogas reforming and prevent the carbon deposition on the anode site. It has been found that CuO-CeO2 and Cu1.3Mn1.7O4 catalysts led to an increase...
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Exsolution of Ni nanoparticles on the surface of cerium and nickel co-doped lanthanum strontium titanate as a new anodic layer for DIR-SOFC. Anti-coking potential and H2S poisoning resistance of the prepared material
PublikacjaThe aim of this study was to evaluate a new catalytic material for biogas fueled DIR-SOFC. This material was a perovskite-type SrTiO3 doped with La, Ce and Ni of a general formula La0.27Sr0.54Ce0.09Ni0.1Ti0.9O3-σ (LSCNT). Additional preparation steps were undertaken to promote a nickel exsolution process. Heat post-treatment of powders in a humidified H2 resulted in an intensive growth of nickel nanoparticles (NPs) while the temperature...
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In situ study of a composition of outlet gases from biogas fuelled Solid Oxide Fuel Cell performed by the Fourier Transform Infrared Spectroscopy
PublikacjaThe purpose of this study was to develop a method and software based on the Fourier Transform Infrared Spectroscopy for the in-situ, quantitative analysis of the composition of outlet gases from Solid Oxide Fuel Cell (SOFC). The calibration procedure performed at the beginning of the experiment indicated a polynomial dependence between the concentration of a calibrating gas (CO, CO2, CH4) and the corresponding integrated absorbance in...
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Powering the Future by Iron Sulfide Type Material (FexSy) Based Electrochemical Materials for Water Splitting and Energy Storage Applications: A Review
PublikacjaWater electrolysis is among the recent alternatives for generating clean fuels (hydrogen). It is an efficient way to produce pure hydrogen at a rapid pace with no unwanted by-products. Effective and cheap water-splitting electrocatalysts with enhanced activity, specificity, and stability are currently widely studied. In this regard, noble metal-free transition metal-based catalysts are of high interest. Iron sulfide (FeS) is one...
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Assessment of fitness for service of Cr-Mo steel tubes in catalytic reforming charge heaters
PublikacjaIn this paper characteristic features of metal dusting corrosion in high temperature gas mixtures of high carbon activity in catalytic reforming units, including Continuous Catalyst Regeneration (CCR) platformer are presented. Examples of 2.25Cr-1Mo and 9Cr-1Mo steel tubes at advanced stages of metal dusting process after long-term service in charge heaters are used to prove that destructive examinations are necessary to provide...