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Wyniki wyszukiwania dla: Hydrogen treated TiO2
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The structure of vanadate glass-ceramics containing BaTiO3 measured with X-ray diffraction method
Dane BadawczeThe structure of vanadate glass-ceramics doped with BaTiO3 was measured by XRD. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated...
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Property-performance relationship of core-shell structured black TiO2 photocatalyst for environmental remediation
PublikacjaUnderstanding the relationship between the properties and performance of black titanium dioxide with core-shell structure (CSBT) for environmental remediation is crucial for improving its prospects in practical applications. In this study, CSBT was synthesized using a glycerol-assisted sol-gel approach. The effect of different water-to-glycerol ratios (W:G = 1:0, 9:1, 2:1, and 1:1) on the semiconducting and physicochemical properties...
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Application of H2O2 to optimize ammonium removal from domestic wastewater
PublikacjaThe paper presents the results of application of hydrogen peroxide (H2O2) for the optimization of the effects of ammonia nitrogen removal from domestic wastewater. The investigations were carried out at a model wastewater treatment plant consisting of a preliminary sedimentation tank and a sand filter with a horizontal flow of wastewater at a constant hydraulic load of 1.44 L/day. The efficiency of ammonia nitrogen removal was...
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Alternative methods for dark fermentation course analysis
PublikacjaDark fermentation course analysis is crucial, as complexed matrix of gaseous components may be formed and revealed during the process. The paper considers key issues related to the microbiological process in which complex organic substances are transformed into hydrogen. For the purposes of hydrogen generation, the application of wastewater mixed sludge pre-treated according to Faloye method (Faloye et al. in Int J Hydrog Energy...
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The morphology of vanadate glass-ceramics containing BaTiO3
Dane BadawczeThe morphology of vanadate glass-ceramic doped with BaTiO3 was measured. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated (573...
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Reduction of the strontium titanate doped by Ytrium ceramics observed by X-ray photoemission spectroscopy method
Dane BadawczeYtrium-doped strontium titanate (YSTF) ceramics materials were manufactured by three various methods: 1) standard solid-state reaction method from Y2O3 (Sigma Aldrich, 99,9%), TiO2 (Sigma Aldrich, 99%) and SrCO3 (Sigma Aldrich,98%), 2) Pechini method, 3) wet method.
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Nonconventional 1,8-Diazafluoren-9-One Aggregates for Green Light Enhancement in Hybrid Biocompatible Media
PublikacjaOrganic aggregates currently play a prominent role, mainly for their unique optoelectronic properties in the aggregated state. Such properties can be related to the aggregates’ structure and the molecular packing mode. In the literature, we have well-established models of H and J aggregates defined based on the molecular exciton model. However, unconventional aggregates, the most unrecognized forms, have been generating interest...
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Występowanie bakterii siarkowych a jakość wód podziemnych ujęcia Osowa
PublikacjaAbstrakt. Microorganisms that live in groundwater should be considered not only from the sanitary-hygienic point of view but also in terms of adverse changes in groundwater chemistry in the aquifer layer and its negative influence on the installed devices. For these reasons, it is important to correct approach to the problem of bacterial contamination of groundwater. The paper presents selected results of physicochemical and bacteriological...
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Laser-assisted modification of titanium dioxide nanotubes in a tilted mode as surface modification and patterning strategy
PublikacjaElectrochemical anodization is regarded as a facile and easily scalable fabrication method of titania nanotubes (TiO2NTs). However, due to the extended duration of calcination and further modifications, much faster alternatives are highly required. As a response to growing interest in laser modification of nanotube arrays, a comprehensive investigation of pulsed-laser irradiation and its effect onto TiO2NT properties has been carried out....
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Linear impedance of vanadate glass-ceramics containing BaTiO3
Dane BadawczeThe linear impedance of vanadate glass-ceramics containing BaTiO3 was measured. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated...
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Effects of Salvia officinalis and Thymus vulgaris on oxidant-induced DNA damage and antioxidant status in HepG2 cells
PublikacjaSalvia officinalis (SO) and Thymus vulgaris (TV) are medicinal plants well known for their curative powers. However, the molecular mechanisms responsible for these abilities of sage and thyme have not been fully understood yet. In this study we investigated the composition and the quantitative estimation of plant extracts, the protective effects of plant extracts against hydrogen peroxide- and 2,3-dimethoxy-1,4 naphthoquinone-induced...
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The structure of vanadate glass-ceramics containing BaTiO3.
Dane BadawczeThe structure of vanadate glass-ceramics doped with BaTiO3 was measured by SEM technique. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on...
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Hydrophilicity of TiO2 exposed to UV and VIS radiation
PublikacjaPo raz pierwszy cienka warstwa TiO2 znajdująca się na powierzchni Pilkington Glass AktivTM została poddana modyfikacji za pomocą amoniaku, tiomocznika i mocznika w celu przesunięcia widma absorpcji w kierunku światła widzialnego. Kąty zwilżania dla wody płytek szklanych Pilkington zostały zmierzone dla próbki niezmodyfikowanej i zmodyfikowanej, która odznaczała się zauważalnym przesunięciem spektrum absorpcyjnego w kierunku VIS.
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Cold plasma treatment of tannic acid as a green technology for the fabrication of advanced cross-linkers for bioactive collagen/gelatin hydrogels
PublikacjaTannic acid (TA) is a natural compound studied as the cross-linker for biopolymers due to its ability to form hydrogen bonds. There are different methods to improve its reactivity and effectiveness to be used as a modifier for biopolymeric materials. This work employed plasma to modify tannic acid TA, which was then used as a cross-linker for fabricating collagen/gelatin scaffolds. Plasma treatment did not cause any significant...
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Influence of alkaline and oxidative pre-treatment of waste corn cobs on biohydrogen generation efficiency via dark fermentation
PublikacjaStages of waste corn cobs processing leading to the production of biohydrogen via dark fermentation are presented and discussed in this paper. Firstly, the effects of pretreatment conditions i.e. alkaline, alkaline-oxidizing and Fenton oxidizing pre-treatment of lignocellulosic biomass on the removal of lignin were examined. The solid residue obtained in the first stage was subjected to saccharification by means of enzymatic hydrolysis....
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Photoelectrochemical characterization of nitrogen-modified TiO2
PublikacjaTrzy próbki tlenku tytanu(IV) o różnej zawartości azotu i różnych właściwościach fotokatalitycznych zostały wybrane do charakterystyki fotoelektrochemicznej. Efektem finalnym jest określenie położenia pasma wzbronionego i pasma przewodzenia w otrzymanych półprzewodnikach.
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Zero-Emissions, Off-grid, Autonomous Houseboat – a Case Study of Selected Locations in Europe
PublikacjaThe aim of this study was to assess the feasibility of creating a prototype of a self-sufficient houseboat that is capable of prolonged independence from power grids and freshwater sources. In this design, electricity demand is met by a photovoltaic installation, and the energy is stored in batteries. Fresh water for living needs may be obtained from many sources, depending on the environmental conditions, such as through purifying...
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Spectacular Oxygen Evolution Reaction Enhancement through Laser Processing of the Nickel‐Decorated Titania Nanotubes
PublikacjaThe selective, laser‐induced modification of the nickel‐decorated titania nanotubes provides remarkable enhancement toward oxygen evolution reaction. Particularly, the irradiation of the laterally spaced crystalline TiO2 nanotubes, results in the formation of the tight closure over irradiated end, preserving their hollow interior. The shape of the absorbance spectra is modulated along with applied energy, and the new absorption...
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Spectacular Oxygen Evolution Reaction Enhancement Through Laser Processing of the Nickel-Decorated Titania Nanotubes
PublikacjaThe selective, laser-induced modification of the nickel-decorated titania nanotubes provides remarkable enhancement toward oxygen evolution reaction. Particularly, the irradiation of the laterally spaced crystalline TiO2 nanotubes, results in the formation of the tight closure over irradiated end, preserving their hollow interior. The shape of the absorbance spectra is modulated along with applied energy, and the new absorption...
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Investigation of Microbes in the Stratosphere – Stardust Project
PublikacjaThe stratospheric microbiota has been investigated many times using the methods of classical microbiology. In this research a few modern methods, including NGS sequencing and multiple displacement amplification of DNA, were in use. The analysis of metagenome helped to determine the content of various species of bacteria in the sample collected in the stratosphere by a hydrogen-filled balloon holding...
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Mission impossible for cellular internalization: When porphyrin alliance with UiO-66-NH2 MOF gives the cell lines a ride
PublikacjaIs it possible to accelerate cell internalization by hybridization of nanomaterials? Herein we support the realization of using metal-organic frameworks (MOFs) with the assistance of rigid porphyrin structure (H2TMP) aimed at drug loading, drug release, relative cell viability, and targeted in vitro drug delivery. There are several MOFs, i.e., UiO-66-NH2 (125 ± 12.5 nm), UiO-66-NH2 @H2TMP (160 ± 14 nm), UiO-66-NH2 @H2TMP@DOX, and...
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Thioacetamide and thiourea impact on visible light activity of TiO2
PublikacjaAktywne w świetle widzialnym fotokatalizatory na bazie tlenku tytanu (IV) przygotowano w wyniku hydrolizy izopropylanu tytanu (IV) z tioacetamidem i tiomocznikiem oraz kalcynacji w temperaturze 450ºC. Wyniki badań wskazują, że fenol i 4-chlorofenol były efektywnie degradowane w obecności domieszkowanego TiO2 oraz światła widzialnego (λ>400 nm). Głównym celem badań było zbadanie wpływu ilość zastosowanego prekursora domieszki...
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Novel Functionalization of Boron-Doped Diamond by Microwave Pulsed-Plasma Polymerized Allylamine Film
PublikacjaWe report the novel modification of a hydrogen-terminated polycrystalline boron-doped electrode with a microwave pulsed-plasma polymerized allylamine. Boron-doped diamond (BDD) was coated with a very thin layer of adherent cross-linked, pinhole- and additive-free allylamine plasma polymer (PPAAm) resistant to hydrolysis and delamination and characterized by a high density of positively charged amino groups. The pulsed microwave...
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Resistance noise in tio2-based thin film gas sensors underultraviolet irradiation
PublikacjaBadano możliwości wykorzystania fluktuacji rezystancji w cienkich warstwach TiO2 do wykrywania gazów. Pomiary przeprowadzono, gdy próbka była oświetlona promieniowaniem ultrafioletowym o długości 370nm, w obecności gazu H2S. Stwierdzono, że fluktuacje rezystancji są indukowane promieniowaniem ultrafioletowym i pozwalają na wykrycie obecności H2S w stężeniu do 1.5 ppm.
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Nonlinear impedance of vanadate glass-ceramics containing BaTiO3
Dane BadawczeThe nonlinear impedance of vanadate glasses doped with BaTiO3 was measured. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated (573...
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Insightful studies of AuCu nanostructures deposited on Ti platform: Effect of rapid thermal annealing on photoelectrochemical activity supported by synchrotron radiation studies
PublikacjaIn this work, we present the influence of annealing atmospheres during rapid thermal annealing (40◦C/s) on nanostructured Ti platforms modified by 10 nm layer of AuCu alloy obtained via magnetron sputtering. The AuCu/Ti platform annealed under hydrogen atmosphere exhibits the best photoelectrochemical activity under visible light, i.e. 27 times higher photocurrent than for pure Ti dimpled platform, and the lowest reflectance with minimum...
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Solvent dependency of carbon dioxide Henry's constant in aqueous solutions of choline chloride-ethylene glycol based deep eutectic solvent
PublikacjaThe Henry's constants of carbon dioxide absorbed in aqueous solutions of ethaline (choline chloride-ethylene glycol) were determined for temperatures ranging from 303.15 to 323.15 K based on solubility measurement at CO2 pressure ranging from 0 to 6 bar (0.6 MPa). These studies revealed that the Henry's constant increased with the increase of temperature. Data indicated the highest capacity of CO2 absorption is obtained for ethaline...
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Optimized photodegradation of palm oil agroindustry waste effluent using multivalent manganese–modified black titanium dioxide
PublikacjaThis article presents a methodological approach to use manganese (Mn3+Mn7+)-modified black titanium dioxide (Mn/BTiO2) as a photocatalyst to optimize and improve visible-light-driven photodegradation of treated agro-industrial effluent (TPOME). A modified wet chemical process was used to prepare BTiO2. The BTiO2 was then wet impregnated with Mn and calcined at 300 °C for 1 h to produce Mn/BTiO2. The activity of Mn/BTiO2 was investigated...
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Visible light-enhanced degradation of phenol in the presence of modified TiO2
PublikacjaOpracowano metody otrzymywania katalizatora na bazie tlenku tytanu (IV) aktywowanego światłem widzialnym do fotokatalitycznego utleniania zanieczyszczeń. Tlenek tytanu (IV) modyfikowano wybranymi organicznymi i nieorganicznymi domieszkami. Aktywność fotokatalityczną otrzymanych próbek katalizatorów zbadano w reakcji degradacji fenolu (co= 0,21 mmol/dm3) w roztworze wodnym, w obecności światła widzialnego (l>400). Wybrane katalizatory...
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Hydration of aprotic donor solvents studied by means of FTIR spectroscopy
PublikacjaThe paper attempts to explain the mutual influence of nonpolar and electron-donor groups on solute hydration,the problem of big importance for biological aqueous systems. Aprotic organic solvents have been used asmodel solutes, differing in electron-donating power. Hydration of acetonitrile, acetone, 2-butanone, andtriethylamine has been studied by HDO and (partially) H2O spectra. The quantitative version of...
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Beyond Antioxidant Activity: Redox Properties of Catechins May Affect Changes in the DNA Methylation Profile—The Example of SRXN1 Gene
PublikacjaThe role of catechins in the epigenetic regulation of gene expression has been widely studied; however, if and how this phenomenon relates to the redox properties of these polyphenols remains unknown. Our earlier study demonstrated that exposure of the human colon adenocarcinoma HT29 cell line to these antioxidants affects the expression of redox-related genes. In particular, treatment with (−)-epigallocatechin (EGC) downregulated...
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Recent Progress on Hydrogen Storage and Production Using Chemical Hydrogen Carriers
PublikacjaDepleting fossil fuel resources and anthropogenic climate changes are the reasons for the intensive development of new, sustainable technologies based on renewable energy sources. One of the most promising strategies is the utilization of hydrogen as an energy vector. However, the limiting issue for large-scale commercialization of hydrogen technologies is a safe, efficient, and economical method of gas storage. In industrial practice,...
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Exploring of electronic structure of nitrogen-modified TiO2 photocatalysts through photocurrent and surface photovoltage studies
PublikacjaPrzeprowadzono pomiary fotonapięcia powierzchniowego i fotoprądu w obecności różnych reduktorów celem otrzymania eksperymentalnego potwierdzenia położenia pasma walencyjnego w strukturze elektronowej tlenku tytanu(IV) modyfikowanego azotem. Zaobserwowano silne sprzężenie poziomów N 2p i O 2p, którego konsekwencją jest powstanie nowego pasma walencyjnego
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Recent advances in hydrogen production from biomass waste with a focus on pyrolysis and gasification
PublikacjaThis paper presents the results research on the optimal fuel compositions and the control parameters of the spark ignition engine fueled with syngas-biogas-hydrogen for the purpose of setting up a flexible electronic control unit for the engine working in a solar-biomass hybrid renewable energy system. In syngas-biogas-hydrogen mixture, the optimal content of hydrogen and biogas is 20% and 30%, respectively. Exceeding these thresholds,...
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Hydrogen-enhanced degradation and oxide effects in zirconium alloys for nuclear applications
PublikacjaThe zirconium alloys used in nuclear industry include mainly ZreSn and ZreNb alloys ofdifferent chemical composition, microstructure and susceptibility to both hydrogendegradation and oxidation. The hypothetic nuclear accidents can create a real danger tothe Zr alloys and stability of parts made of these alloys, and especially such as loss ofcoolant accident (LOCA) and reactivity initiated accidents (RIA). The hydrogen degradationcan...
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Catalysts for advanced oxidation processes: Deep eutectic solvents-assisted synthesis – A review
PublikacjaNew catalyst synthesis techniques, including green materials, are extensively studied for heterogeneous photocatalytic advanced oxidation processes (AOPs) on spotlight of sustainable development. Deep eutectic solvents (DESs) started to be used in this field as environmentally friendly alternative to ionic liquids (ILs). During the catalyst synthesis, DESs can act as stabilizers, capping agents, structure directing agents, templates,...
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Effect of TiO2 Concentration on Microstructure and Properties of Composite Cu–Sn–TiO2 Coatings Obtained by Electrodeposition
PublikacjaIn this work, Cu–Sn–TiO2 composite coatings were electrochemically obtained from a sulfate bath containing 0–10 g/L of TiO2 nanoparticles. The effect of TiO2 particles on kinetics of cathodic electrodeposition has been studied by linear sweep voltammetry and chronopotentiometry. As compared to the Cu–Sn alloy, the Cu–Sn–TiO2 composite coatings show rougher surfaces with TiO2 agglomerates embedded in the metal matrix. The highest...
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Bismuth-based nanomaterials-assisted photocatalytic water splitting for sustainable hydrogen production
PublikacjaThe rapidly increase in the world's population has resulted in a corresponding increase in the energy demand. This demand is largely being met by fossil fuels for power generation, industrial fuel and transportation. However, due to the limited availability of fossil fuels and their negative effects on the environment. The use of fossil fuels results in by-products such as carbon, nitrogen and sulfur oxides which have negative...
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Bismuth-based nanomaterials-assisted photocatalytic water splitting for sustainable hydrogen production
PublikacjaThe rapidly increase in the world's population has resulted in a corresponding increase in the energy demand. This demand is largely being met by fossil fuels for power generation, industrial fuel and transportation. However, due to the limited availability of fossil fuels and their negative effects on the environment. The use of fossil fuels results in by-products such as carbon, nitrogen and sulfur oxides which have negative...
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Fotokataliza z wykorzystaniem TiO2
PublikacjaOpisano podstawy teoretyczne fotokatalizy z wykorzystaniem TiO2 i mechanizmzanieczyszczeń oraz fizykochemię powierzchni półprzewodnikowych tlenków me-tali. Opisano również zastosowanie TiO2 do oczyszczania wód i ścieków orazdo degradacji zanieczyszczeń w fazie gazowej.
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Influence of hydrogen on a nanocrystalline high-entropy oxide with application potential in hydrogen technologies
PublikacjaThe influence of hydrogen on a (Co0⋅2Cu0⋅2Mg0⋅2Ni0⋅2Zn0.2)O HEO with a rock salt structure was studied. Two forms of this HEO (nanopowder and sinter) were prepared via mechanochemical synthesis (MS) and additional heat treatment, respectively. The chemical stability of the synthesized samples in a pure hydrogen atmosphere was investigated using Sievert’s technique. High-pressure hydrogenation at 250 ◦C had no noticeable effect...
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Photodegradation of phenol by UV/TiO2 and Vis/N,C-TiO2 processes: Comparative mechanistic and kinetic studies
PublikacjaPorównano drogę fotodegradacji w dwóch systemach badawczych: UV/TiO2 i Vis/N,C-TiO2. Zbadano efektywność degradacji fenolu, powstające produkty pośrednie oraz generowanie rodników hydoksylowych w przygotowanych układach badawczych. Wyniki badań wykazały porównywalne efektywności degradacji fenolu w zawiesinach: domieszkowany TiO2/Vis i TiO2 P-25/UV. Uzyskane wyniki wskazują również na odmienne drogi degradacji zanieczyszczeń w...
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SEM - Expanded polystyrene coated by TiO2 or SiO2-TiO2
Dane BadawczeData contain SEM images taken in SEM Hitachi SU8000 with voltage of 5.0 kV. SEM images show expanded plystyrene spheres coated by a thin layer of TiO2 or bilayer SiO2-TiO2.
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Diffusible hydrogen management in underwater wet self-shielded flux cored arc welding
PublikacjaThis article reports the effect of underwater wet welding parameters and conditions on the diffusible hydrogen content in deposited metal for welding with a self-shielded flux cored wire. The diffusible hydrogen content in deposited metal was determined using the glycerin method according to the Plackett-Burman design determining the significance of the effect of the stick out length, welding current, arc voltage, travel speed...
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The ILs-assisted solvothermal synthesis of TiO2 spheres: the effect of ionic liquids on morphology and photoactivity of TiO2
PublikacjaEffect of the ionic liquid (IL) structure (chain length in the imidazolium cation) on morphology and photoactivity of TiO2 particles has been systematically investigated. The TiO2 microspheres have been successfully synthesized via facile solvothermal method assisted by ionic liquids, such as 1-butyl-3-methylimidazolium chloride [BMIM][Cl] and 1-decyl-3-methylimidazolium chloride [DMIM][Cl] using tetra-tert-butyl orthotitanate...
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The effect of microemulsion composition on the morphology of Pd nanoparticles deposited at the surface of TiO2 and photoactivity of Pd-TiO2
PublikacjaA series of microemulsion (ME) system, constituted by different water to surfactant molar ratios (Wo) and oil to surfactant mass ratios (S), have been applied for Pd-TiO2 preparation. The effect of ME properties on the morphology of Pd nanoparticles formed at TiO2 surface and an effect of Pd size and distribution on the surface and photocatalytic properties of Pd-TiO2 were investigated. Microemulsion systems were characterized...
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Electrical and mechanical properties of nitrided sol-gel derived TiO2 and SiO2-TiO2 films
PublikacjaW pracy opisano właściwości elektryczne i mechaniczne cienkich warstw zawierających TiN. Warstwy tlenkowe TiO2 i TiO2-SiO2 zostały przygotowane metodą zol-żel i następnie poddane procesowi amonolizy. Przewodność elektryczna została zmierzona w zaktesie temperatur 10-900K. Warstwy o dużej zawartości TiN charakteryzują się małą energią aktywacji, poniżej 0,1eV. Badania wykazały dużą twardość próbek o wysokiej zawartości TiN.
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Application of atmospheric pressure microwave plasma source for hydrogen production from ethanol
PublikacjaIn contrast to conventional technologies of hydrogen production like water electrolysis or coal gasification we propose a method based on the atmospheric pressure microwave plasma. In this paper we present results of the experimental investigations of the hydrogen production from ethanol in the atmospheric pressure plasma generated in waveguidesupplied cylindrical type nozzleless microwave (915 MHz and 2.45 GHz) plasma source (MPS)....
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Crystal facet effects in photocatalytic degradation of organic pollutants over anatase TiO2
PublikacjaPresented work show detailed effect of the exposed crystal facets of anatase TiO2 on the photocatalytic degradation of organic pollutants. The most important existing information about the geometry and electronic properties of the low index anatase facets are summarised. During the performed works, anatase nanoparticles with the dominant exposition of either {0 0 1}, {1 0 0} or {1 0 1} crystal facets were prepared and their photocatalytic...
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Fotokatalityczne właściwości TiO2
PublikacjaFotokataliza to reakcja zachodząca na skutek absorpcji światła przez fotokatalizator lub substrat. Fotokatalizator to substancja, która wpływa korzystnie na przebieg reakcji zachodzącej pod wpływem światła i sama nie ulega zużyciu. Dobry fotokatalizator powinien wykazywać wysoką aktywność fotokatalityczną. Wśród półprzewodników wykazujących działanie fotokatalityczne w reakcjach degradacji związków organicznych za najbardziej efektywny...