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Search results for: vanadium oxides
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Dichlorido-1Cl,3Cl-hexakis[1,1,2,2,3,3(n5)-methylcyclopentadienyl]di-μ2-oxido-1:2κ2O:O;2:3κ2O:O-trihafnium(IV)
PublicationTytułowy związek jest trójrdzeniową cząsteczką. Dwie jednostki (MeCp)2HfCl połączone są z (MeCp)2Hf przez mostki tlenowe. Mostki Hf-O-Hf są prawie liniowe. Geometria trzech atomów Hf jest tetraedryczna.
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Fabrication of La-Doped Bi4Ti3O12 Ceramics
PublicationLa-modified Bi4Ti3O12 is a typical ferroelectric, piezoelectric and electro-optic material, having relatively low coercive field, low dielectric constant, high Curie temperature and high breakdown strength. Goal of the present research was to apply mixed oxide method for fabrication of BiTLax ceramics, study its chemical composition, crystalline structure and microstructure. The compound BiTLax for x=0, 0.25, 0.5, 0.75 ceramic...
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Remarks on evaluation of spectral radius of operators arising in WR methods for linear systems of ODEs
PublicationW pracy omawiane są różne metody oszacowania promienia spektralnego. Do oszacowań tych użyto elementarnych metod. Jedną z nich jest metoda wykorzystująca normę Bieleckiego. Jedną z zalet takich metod wyraźnie widać na przykładzie równań różniczkowych z opóźnieniem, gdzie oszacowania promienia spektralnego zależą od charakteru opóźnienia.
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Fabrication and Structural Properties of LaNb 1‐x As x O 4 Ceramics
PublicationLanthanum niobate substituted with arsenic was synthesized by three methods: solid state reaction from binary oxides and two different methods combining co-precipitation and solidstate reaction. In the first of the combined methods LaNb1- xAsxO4 was synthesized from LaAsO4, obtained from coprecipitation method, and lanthanum and niobium oxides. In the second LaNbO4 was first synthesized from binary oxides and then mixed with LaAsO4...
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Lower-rim-substituted tert-butylcalix[4]arenes. Part IX: one-pot synthesis of calix[4]arene-hydroxamates and calix[4]arene-amides
PublicationZaprezentowano prostą metodę selektywnej acylacji podstawionych i niepodstawionych hydroksyloamin za pomocą di i tetra podstawionych kaliks{4]aren-kwasów. Pokazano pierwszą strukturę krystalograficzną kaliks-hydroksyamidu.
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Phytochemical screening and effect of Viscum album L. on monoamine oxidase A and B activity and serotonin, dopamine and serotonin receptor 5-HTR1A levels in Galleria mellonealla (Lepidoptera)
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Lower rim substituted tert-butylcalix[4]arenes. Part 10. New Pb(II)-selective electrodes based on tetrasubstituted calix[4]arenes amides
PublicationOpracowano elektrody selektywne na jony Pb(II) oparte na lipofilowych tetrapodstawionych amidowych pochodnych kaliks[4] arenu. Charakterystyki elektrod mają nachylenie nernstowskie w szerokim zakresie stężeń 10 (-1.3) do 10 (-7.2).
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Preparation of Allyl Alcohol Oligomers Using Dipicolinate Oxovanadium(IV) Coordination Compound
PublicationCurrently, new precatalysts for olefin oligomerization are being sought in the group of vanadium(IV) complexes. Thus, the aim of our research was to examine the catalytic activity of the oxovanadium(IV) dipicolinate complex [VO(dipic)(H2O)2] 2 H2O (dipic = pyridine-2,6-dicarboxylate anion) in 2-propen-1-ol oligomerization as well as to characterize oligomerization products using matrix-assisted laser desorption/ionization–time-of-flight...
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Effect of Semiconductor Element Substitution on the Electric Properties of Barium Titanate Ceramics
PublicationThe investigated ceramics were prepared by a solid-state reaction from simple oxides and carbonates with the use of a mixed oxide method (MOM). The morphology of BaTi0.96Si0.04O3 (BTSi04) ceramics was characterised by means of a scanning electron microscopy (SEM). It was found that Si+4 ion substitution supported the grain growth process in BT-based ceramics. The EDS results confirmed the high purity and expected quantitative composition...
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NOx Photooxidation over Different Noble Metals Modified TiO2
PublicationWe compared the activity enhancement effect of noble metal deposited on TiO2 in photocatalytic nitrogen oxides oxidation. Titanium dioxide was decorated with Ag, Au, Pt or Pd in the sol-gel process. Synthesized catalysts were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller measurement (BET), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX)....
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Cost-effective methods of fabricating thin rare-earth element layers on SOC interconnects based on low-chromium ferritic stainless steel and exposed to air, humidified air or humidified hydrogen atmospheres
PublicationMost oxidation studies involving interconnects are conducted in air under isothermal conditions, but during real-life solid oxide cell (SOC) operation, cells are also exposed a mixture of hydrogen and water vapor. For this study, an Fe–16Cr low-chromium ferritic stainless steel was coated with different reactive element oxides – Gd2O3, CeO2, Ce0.9Y0.1O2 – using an array of methods: dip coating, electrodeposition and spray pyrolysis....
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Ocena odporności na zużycie ścierne stopów Ti na elementy pary trącej endoprotez stawu kolanowego
PublicationNajczęściej stosowanym biomateriałem tytanowym na elementy endoprotez stawu kolanowego jest stop Ti6Al4V. Z uwagi na zawartość wanadu, zaliczanego do pierwiastków o dużej toksyczności podejmowane są działania w kierunku zastąpienia wskazanego stopu - stopami bezwanadowymi. Jednym z najbardziej obiecujących jest stop Ti13Nb13Zr zawierający w swoim składzie jedynie pierwiastki witalne, niewywołujące stanów zapalnych i odczynów...
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Direct reduction of pellets through hydrogen: Experimental and model behaviour
PublicationThis paper presents the hydrogen reduction behaviour of industrial pellets designed for the efficient hydrogen based direct reduction. The pellets were provided with very low non ferrous oxides percentage (0.52 of basicity index) and with the absence on TiO2 oxides. The pellets measured diameters in the range 1.14–1.72 cm and were characterized in terms of porosity, pores size, tortuosity and compression strength. The pellets were...
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Application of polyethylene glycol-coated iron oxide nanoparticles for magnetic solid phase extraction of copper from seawater samples and its determination by graphite furnace atomic absorption spectrometry using response surface methodology for optimization of extraction
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Vibrational Properties of LaNb0.8M0.2O4-δ (M=As, Sb, V, and Ta)
PublicationLaNb0.8M0.2O4-δ (where M=As, Sb, V, and Ta) oxides with pentavalent elements of different ionic sizes were synthesized by a solid-state reaction method. The vibrational properties of these oxides have been investigated. These studies revealed that the substituent element influences both Debye temperature value as well as the Raman active vibrational modes. Additionally, the low-temperature vibrational properties of LaNb0.8Sb0.2O4-δ...
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The CON−H…+NH2 Blue-Shifting H-Bond Stabilizing Effect on Z Secondary Amides and Cyclic System Conformational Rearrangement through an Alkylamine-Chain Migration Pathway
PublicationThe paper is focusing on the amide linkage exceptional properties and usage of chemistry (conformational rearrangement, geometrical stereoisomers, spectroscopic blue shift phenomenon, protonation and deprotonation reactions, synthetic scope, and mechanistic implications). Hydrogen-bond-stabilized acylation reactions of a diamine with thioamides or nitriles reveal how substituents influence both the outcome of stereoselectivity...
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Fully scalable one-pot method for the production of phosphonic graphene derivatives
PublicationGraphene oxide was functionalized with simultaneous reduction to produce phosphonated reduced graphene oxide in a novel, fully scalable, one-pot method. The phosphonic derivative of graphene was obtained through the reaction of graphene oxide with phosphorus trichloride in water. The newly synthesized reduced graphene oxide derivative was fully characterized by using spectroscopic methods along with thermal analysis. The morphology...
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AN OVERVIEW OF HEAT TRANSFER ENHANCEMENT BASED UPON NANOPARTICLES INFLUENCED BY INDUCED MAGNETIC FIELD WITH SLIP CONDITION VIA FINITE ELEMENT STRATEGY
PublicationThe mathematical model of heat generation and dissipation during thermal energy transmission employing nanoparticles in a Newtonian medium is investigated. Dimensionless boundary layer equations with correlations for titanium dioxide, copper oxide, and aluminium oxide are solved by the finite element method. Parameters are varied to analyze their impact on the flow fields. Various numerical experiments are performed consecutively...
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Wpływ procesu redukcji na właściwości strukturalne i mechaniczne szkieł tlenkowych z grupy (Pb,Bi)-(Si,Ge)-O = Influence of reduction process on the structural and mechanical properties of (Pb,Bi)-(Si,Ge)-O oxide glasses
PublicationThe effect of the reduction process in H2 at 380 °C on the microstructure and elemental composition of a glass Bi0.4Pb0.2Si0.4Ox has been investigated. It has been shown that after reduction a clearly separated top layer with a thickness of approx. 50 µm was formed on the surface of the sample. This layer is depleted of oxygen and has higher electrical conductivity than the interior of the glass. It has also been found that some...
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Characteristics of La 0.8 Sr 0.2 Ga 0.8 Mg 0.2 O 3-δ -supported micro-tubular solid oxide fuel cells with LaCo 0.4 Ni 0.6-x Cu x O 3-δ cathodes
PublicationIn this study, micro-tubular solid oxide fuel cells (T-SOFCs) with extruded La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) electrolyte as the mechanical support and LaCo0.4Ni0.6O3-δ (LCNO) or LaCo0.4Ni0.4Cu0.2O3-δ (LCNCO) as cathodes were prepared and characterized. Partial substitution of Cu for the Ni-ion positions in the LCNO lattices was found to significantly enhance the densification and accelerate the grain growth. The porosity-corrected...
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Optimizing conductivity in Na-V-Te-O glass through controlled heat treatment
PublicationSemiconducting Na2O-V2O5-TeO2 glasses with various Na2O contents were melted and subjected to controlled heating to improve conductivity. Topography analysis were performed using confocal microscopy and scanning electron microscopy on both as-quenched and heat-treated samples. X-ray diffraction confirmed the amorphous nature of the samples post-melting, with subsequent heating resulting in the formation of nanocrystallites primarily...
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Experimental study on the effect of selected sterilization methods on mechanical properties of polylactide FFF specimens
PublicationPurpose: Biodegradable polymers are widely used in personalized medical devices or scaffolds for tissue engineering. The manufacturing process should be finished with sterilization procedure. However, it is not clear how the different sterilization methods have an impact on the mechanical strength of the three-dimensional (3D)-printed parts, such as bone models or personalized mechanical devices. This paper aims to present the...
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Therapeutic Potential of Multifunctional Derivatives of Cholinesterase Inhibitors
PublicationThe aim of this work is review of tacrine analogues from the last three years, which were not included in the latest review work, donepezil and galantamine hybrids from 2015 and rivastigmine derivatives from 2014. In this account we summarize the efforts toward the development and characterization of non-toxic inhibitors of cholinesterases based on mentioned drugs with various interesting additional properties such as antioxidant,...
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Endothelial dysfunction due to eNOS uncoupling: molecular mechanisms as potential therapeutic targets
PublicationNitric oxide (NO) is one of the most important molecules released by endothelial cells, and its antiatherogenic properties support cardiovascular homeostasis. Diminished NO bioavailability is a common hallmark of endothelial dysfunction underlying the patho‑ genesis of the cardiovascular disease. Vascular NO is synthesized by endothelial nitric oxide synthase (eNOS) from the substrate L‑arginine (L‑Arg), with tetrahydrobiopterin...
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Evaluation of Selected Heavy Metal Contaminants as Well as Nitrates and Nitrites in the Microgreens of Nigella (Nigella sativa L.), Safflower (Carthamus tinctorius L.), and Camelina (Camelina sativa L.) at Different Stages of Vegetation
PublicationMicrogreens are a new, rapidly growing group of foodstuffs. The decorative function of these is often accompanied by their use in traditional dishes. As microgreens are eaten at very early stages, when the development of the epidermis is at its minimum, the bioavailability of minerals will be found to be higher in microgreens then in mature vegetables. So, microgreens can be an excellent functional food, especially for mineral-deficient...
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The ability of new sugar-modified derivatives of antitumour anthracycline, daunorubicin, to stimulate NAD(P)H Oxidation in Different Cellular Oxidoreductase Systems: NADH Dehydrogenase, NADPH Cytochrome P450 Reductase, and Xanthine Oxidase.
PublicationUboczne działanie cytostatyków z grupy antracyklin prowadzi do uszkodzenia serca (kardiotoksyczność) w wyniku pośredniczenia przez te związki przeniesienia jednoelektronowego ze zredukowanych nukleotydów do tlenu i powstania reaktywnych anionorodników tlenowych. Proces ten jest katalizowany głównie przez trzy enzymy: dehydrogenazę NADH, reduktazę NADPH/cytochrom P450 oraz oksydazę ksantynową. W publikacji przedstawione są wyniki...
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Laboratory station for research of the innovative dry method of exhaust gas desulfurization for an engine powered with residual fuel
PublicationContemporary methods of exhaust gas desulfurization in marine engines are all expensive methods (4-5 million euro). This is, among other reasons, due to the limited market audience, but primarily due to the monop-olized position of manufacturers offering fabrication and assembly of this type of marine ship installations. Proposed as part of a research project financed by the Regional Fund for Environmental Protection and Maritime...
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Investigations of the Working Process in a Dual-Fuel Low-Emission Combustion Chamber for an FPSO Gas Turbine Engine
PublicationThis investigation is devoted to an analysis of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. The low-emission gas turbine combustion chamber with partial pre-mixing of fuel and air inside the outer and inner radial-axial swirlers was chosen as the object of research. When modelling processes in a dual-flow low-emission gas turbine combustion chamber, a generalized method...
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Influence of titanium layer on counter electrode on electrical parameters of DSSC
PublicationIn this paper the influence of the Ti layer thickness at counter-electrode on electrical parameters of DSSCs was examined. The transparent conductive oxide – less (TCO-less) counter electrodes (CE) with titanium layers and platinum as catalyst on Bk7 glass were prepared. Thin metallic films were deposited by means of magnetron sputtering (titanium) and Pulsed Laser Deposition (platinum). The counter electrode with Pt layer on Fluorine...
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Application of Impedance Spectroscopy for Bi1−xNdxFeO3 Ceramics Characterization
PublicationIn the present paper the synthesis conditions for fabrication of Bi1−xNdxFeO3 ceramics are reported. The single phase polycrystalline samples of Bi1−xNdxFeO3 were prepared by standard solid state reaction method from the mixture of oxides viz.: Bi2O3, Fe2O3 and Nd2O3. The samples were characterized by impedance spectroscopy in the frequency range 10Hz – 1MHz at room temperature.
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Influence of processing conditions on crystal structure of BiNbO 4 ceramics
PublicationBismuth niobate (BiNbO4) has attracted attention as a low-fired ceramics with promising microwave application potential. It belongs to the bismutocolumbite oxides with similarly to scheelite-like stibiotantalite structure (SbTaO4) A3+B5+O4. Aim of the present research was to fabricate BiNbO4 ceramics by solid state reaction route from the mixture of simple oxides viz. Bi2O3, and Nb2O5, and study its phase composition as well as...
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STUDY OF CuO AND V2O5 EFFECT ON IR SPECTRA OF POLYCRYSTALLINE BISMUTH NIOBATE
PublicationBismuth niobate (BiNbO4) ceramics were fabricated by mixed oxide method and sintered by presureless sintering method. BiNbO4 ceramics doped with V2O5 additive in amount 0.125 wt%, 0.250 wt% and 1 wt% of was sintered at T = 910°C whereas BiNbO4 ceramics doped with 2 wt% of CuO additive was sintered at T = 890°C and T = 910°C. It was found that V2O5 additive improved morphology of the ceramic samples. However, the chemical composition...
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Submicron inorganic particles as an additional filler in hybrid epoxy matrix composites reinforced with glass fibres
PublicationIn this study, the effect of selected submicron metal oxide (zinc oxide, titanium oxide) or non-metal oxide (silicon dioxide) particles on mechanical and thermo-mechanical properties of epoxy/glass composites was investigated. The applied epoxy resin was a diglycidyl ether of bisphenol-A cured with triethylenetetramine. As a reinforcement twill weave E-glass fabric was used. Hybrid composites (contained particulate and fibrous...
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Influence of operation temperature instability on gas sensor performance
PublicationGas sensors based on the semiconducting metal-oxides, such as SnO2, have been found to be very useful for detecting a wide range of gases. The reversible interactions of the gas with the surface of the sensing layer made of semiconducting metal-oxides are responsible for changes of sensor resistance which is usually used as a measure of sensor response. Semiconductor gas sensors are commercially available and applied in numerous...
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Energetics of formation and stability in high pressure steam of barium lanthanide cobaltite double perovskites
PublicationThis 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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Conductivity, structure, and thermodynamics of Y2Ti2O7–Y3NbO7 solid solutions
PublicationThe defect fluorite yttrium niobate Y3NbO7 and pyrochlore yttrium titanate Y2Ti2O7 solid solutions have been synthesized via a solid state synthesis route. The resulting stoichiometry of the oxides is Y2+xTi2−2xNbxO7, where x = 0 to x = 1. All of the samples were single-phase; however, for those with a predominant fluorite phase, a small amount of additional pyrochlore phase was detected. The volume of the solid solution unit cells...
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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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Microwave-assisted synthesis of a TiO2-CuO heterojunction with enhanced photocatalytic activity against tetracycline
PublicationA microwave method was used for the synthesis of TiO2-CuO oxide systems. A detailed investigation was made of the effect of the molar ratio of components (TiO2:CuO=9:1, 7:3, 5:5, 3:7, 1:9) on the crystalline structure and morphology. Transmission electron microscopy (TEM) confirmed the presence of octahedral and rod-shaped titania particles and sheet copper(II) oxide particles; moreover, HRTEM analysis indicated the presence of...
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Oxidation and hydrogen behavior in Zr-2Mn alloy
PublicationThe purpose of the present research was to determine the oxidation and hydrogenation behavior in the new Zr-2Mn alloy. The oxidation of alloy was performed at temperatures between 350°C and 900°C for 30 minutes. The hydrogen charging was made for 72 h at a current density 80 mA/cm2. The charged samples were heat treated at 400°C for 4 h to obtain a uniform hydrogen profile content across the sample. The oxidation resulted in an...
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Effect of Bi2O3 Excess on Morphology and Structure of BiNbO4 Ceramics
PublicationGoal of the present research was to fabricate BiNbO4 ceramics from the mixture of powders by the solid state reaction route and pressureless sintering at various temperatures (TS =8700C and TS =9100C) and study microstructure, phase composition and crystalline structure of BiNbO4 ceramics. Four batches were fabricated and examined, namely the one fabricated from the stoichiometric mixture of reagent – grade oxide powders, viz....
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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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Speciation of heavy metals in bottom sediments of drinking water reservoir for Gdansk, Poland – changes over the 14 years
PublicationThere was conducted a comparative study of the concentrations of heavy metals (Zn, Cu, Pb, and Cd) in the surface layer of sediments collected in two investigation periods: 1999–2000 and 2013. Theresults demonstrated that the degree of metals pollution decreased over time. The contamina-tion factors (Cf) calculated for Zn, Cu, Pb, and Cd were respectively 3.63, 3.86, 3.23, and 3.25 in the first period of research and 1.35, 3.42,...
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Synthesis of highly crystalline photocatalysts based on TiO2 and ZnO for the degradation of organic impurities under visible-light irradiation
PublicationA TiO2–ZnO binary oxide system (with molar ratio TiO2:ZnO = 8:2) was synthesized by a hydrothermal method, assisted by calcination at temperatures of 500, 600 and 700 °C, using zinc citrate as the precursor of ZnO. The morphology (SEM, TEM), crystalline structure (XRD, Raman spectroscopy), diffuse reflectance spectra (DRS), chemical surface composition (EDXRF), porous structure parameters (low-temperature N2 sorption) and characteristic...
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Study of the NO2 sensing mechanism of PEDOT-RGO film using in situ Raman Spectroscopy
PublicationIn this work, the mechanism of the NO2 reaction with PEDOT-RGO composite film has been investigated via in situ Raman spectroscopy. Reduced graphene oxide (RGO), poly(3,4-ethylenedioxytiophene)-reduced graphene oxide (PEDOT-RGO) and poly(3,4-ethylenedioxytiophene)/ClO4− (PEDOT/ClO4−) films were fabricated using an electrodeposition method and used as resistance sensors of gaseous nitrogen dioxide. The experimental results indicate...
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Nanolayers in Fiber-Optic Biosensing
PublicationIn this chapter, fiber-optic sensors based on nanolayers or thin films and their ability to perform biophotonic measurements is presented. In the last decade, fiber-optic sensors have gained popularity as biosensing devices. This has been made possible because of the design and the integration of new materials in fiber-optic technology. Nanolayers and thin films made from various materials such as nanodiamond (NCD), boron-doped...
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Elctrochemical oxidation and corrosion resistance of the Ti13Nb13Zr alloy
PublicationThis paper presents the results of oxidation and corrosion tests carried out on titanium alloy Ti13Nb13Zr. The oxide film was prepared by electrochemical environment 2M H3PO4 for 30 min and 1 h, at a constant voltage 40V. The tests of corrosion resistance were performed by potentiostatic method in Ringer's solution at different pH values: 7, 5 and 3. The change in an appearance of surface and the increase in corrosion resistance...
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Analysis of MArkers of Exposure to Constituents of Environmental Tobacco Smoke (ETS)
PublicationTobacco smoke is a complex mixture of more than 4000 chemical compounds, many of which are harmful to human health. These compounds belong to various chemical classes, including amides, imides, lactams, carboxylic acids, aldehydes, ketones, alcohols, phenols, amines, hydrocarbons, ethers, and inorganic compounds. There are three types of tobacco smoke streams: the mainstream, the sidestream, and environmental tobacco smoke (ETS)....
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The mechanisms of degradation of titanium dental implants
PublicationTitanium dental implants show very good properties, unfortunately there are still issues regarding material wear due to corrosion, implant loosening, as well as biological factors—allergic reactions and inflammation leading to rejection of the implanted material. In order to avoid performing reimplantation operations, changes in the chemical composition and/or modifications of the surface layer of the materials are used. This research...
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Catalysts for advanced oxidation processes: Deep eutectic solvents-assisted synthesis – A review
PublicationNew 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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Speciation of heavy metals in bottom sediments of a drinking water reservoir for Gdańsk, Poland – changes over the 14 years
PublicationThere was conducted a comparative study of the concentrations of heavy metals (Zn, Cu, Pb, andCd) in the surface layer of sediments collected in two investigation periods: 1999–2000 and 2013.The results demonstrated that the degree of metals pollution decreased over time. The contaminationfactors (Cf) calculated for Zn, Cu, Pb, and Cd were respectively 3.63, 3.86, 3.23, and 3.25 in thefirst period of...