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Wyniki wyszukiwania dla: EXCITATION, DISSOCIATION, IONISATION, COLLISION SPECTROSCOPY, PHOTOELECTRON SPECTRA, SYNCHROTRON RADIATION
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Study of Direct Methanol Fuel Cell Process Dynamics Using Dynamic Electrochemical Impedance Spectroscopy
PublikacjaA new technique, which was developed to characterize the direct methanol fuel cell under work conditions, has been presented in this paper. The impedance measurements were made using dynamic electrochemical impedance spectroscopy research technique in the galvanostatic mode, using multiple sinusoidal excitation. Obtained results show, that together with an increase of the temperature and working load, the global impedance...
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Thin layer of ordered boron-doped TiO2 nanotubes fabricated in a novel type of electrolyte and characterized by remarkably improved photoactivity
PublikacjaThis paper reports a novel method of boron doped titania nanotube arrays preparation by electrochemical anodization in electrolyte containing boron precursor – boron trifluoride diethyl etherate (BF3 C4H10O), simultaneously acting as an anodizing agent. A pure, ordered TiO2 nanotubes array, as a reference sample, was also prepared in solution containing a standard etching compound: ammonium fluoride. The doped and pure titania...
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Low energy inelastic electron scattering from carbon monoxide: II. Excitation of the b3Σ+, j3Σ+, B1Σ+, C1Σ+ and E1Π Rydberg electronic states
PublikacjaIn this second part of a two part paper (first part: Zawadzki et al (2020 J. Phys. B: At. Mol. Opt. Phys. 53 165201)) we present differential scattering cross sections for excitation of several Rydberg electronic states of carbon monoxide by electron impact. The first part concerned the low-lying valence states of CO. In the present study cross sections are obtained experimentally using low-energy electron energy-loss spectroscopy...
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The changes of outlet gases concentrations from SOFC with Ce(Pr,Sm)O2-s layers
Dane BadawczeThe dataset includes The changes of outlet gases concentrations from SOFC with Ce(Pr,Sm)O2-s layers. Samples were produced using aqueous soft chemistry methods (microemulsion method) and applied in form of a layer onto the anode of the commercial SOFC. The SOFC was working under biogas feeding.
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The influence of intermolecular correlations on the infrared spectrum of liquid dimethyl sulfoxide
PublikacjaDimethyl sulfoxide (DMSO) is routinely applied as an excellent, water-miscible solvent and chemical reagent. Some of the most important data concerning its liquid structure were obtained using infrared (IR) spectroscopy. However, the actual extent of intermolecular correlations that connect the isolated monomer spectrum to the IR response of the bulk liquid is poorly studied thus far. Using ab initio molecular dynamics (AIMD) simulations,...
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Defective TiO2 Core-Shell Magnetic Photocatalyst Modified with Plasmonic Nanoparticles for Visible Light-Induced Photocatalytic Activity
PublikacjaIn the presented work, for the first time, the metal-modified defective titanium(IV) oxide nanoparticles with well-defined titanium vacancies, was successfully obtained. Introducing platinum and copper nanoparticles (NPs) as surface modifiers of defective d-TiO2 significantly increased the photocatalytic activity in both UV-Vis and Vis light ranges. Moreover, metal NPs deposition on the magnetic core allowed for the effective separation...
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Rubrene Thin Films with Viably Enhanced Charge Transport Fabricated by Cryo-Matrix-Assisted Laser Evaporation
PublikacjaAmong organic semiconductors, rubrene (RB; C42H28) is of rapidly growing interest for the development of organic and hybrid electronics due to exceptionally long spin diffusion length and carrier mobility up to 20 cm2V−1s−1 in single crystals. However, the fabrication of RB thin films resembling properties of the bulk remains challenging, mainly because of the RB molecule’s twisted conformation. This hinders the formation of orthorhombic...
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XPS study of the YST ceramics
Dane BadawczeYttrium-doped strontium titanate was prepared via conventional solid-state reaction method from Y2O3 (Sigma Aldrich, 99,9%), TiO2 (Sigma Aldrich, 99%) and SrCO3 (Sigma Aldrich,98%). For comparision, two other techniques were used for synthesis: Pechini and wet methods. Both kind of samples were measured, after and before reduction process (in a hydrogen)....
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The electrochemical response to BDD electrode functionalization with CD147 receptor
Dane BadawczeThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with CD147 receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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The electrochemical response to BDD electrode functionalization with ACE2 receptor
Dane BadawczeThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with ACE2 receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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The electrochemical response to BDD electrode functionalization with IgG2B receptor
Dane BadawczeThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with IgG2B receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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Perovskite-type KTaO3–reduced graphene oxide hybrid with improved visible light photocatalytic activity
PublikacjaNovel rGO–KTaO3 composites with various graphene content were successfully synthesized using a facile solvothermal method which allowed both the reduction of graphene oxide and loading of KTaO3 nanocubes on the graphene sheets. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX), Fourier...
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Novel nitrogen precursors for electrochemically driven doping of titania nanotubes exhibiting enhanced photoactivity
PublikacjaNitrogen doped titania nanotubes were successfully sensitized by electrochemical method, i.e. as-anodized titania was immersed in different amine (diethyleneamine-DETA, triethyleneamine-TEA, ethylenediamine-EDA) and urea (U) solution and a constant potential was applied. The highly ordered morphology of fabricated N-TiO2 was investigated by using scanning electron microscopy. Spectroscopic techniques, i.e. UV-Vis spectroscopy,...
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Preparation and Characterization of Defective TiO2. The Effect of the Reaction Environment on Titanium Vacancies Formation
PublikacjaAmong various methods of improving visible light activity of titanium(IV) oxide, the formation of defects and vacancies (both oxygen and titanium) in the crystal structure of TiO2 is an easy and relatively cheap alternative to improve the photocatalytic activity. In the presented work, visible light active defective TiO2 was obtained by the hydrothermal reaction in the presence of three different oxidizing agents: HIO3, H2O2, and...
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Determination of API content in a pilot-scale blending by near-infrared spectroscopy as a first step method to process line implementation
PublikacjaNear infrared (NIR) spectroscopy was used for estimation of powder blend homogeneity and manufacturing control of a medicinal product powder mixture containing active pharmaceutical ingredient (API). Aiming at initiating a Process Analytical Technology (PAT) activity, the first step was a stationary mode atline evaluation. In this, the content of pharmaceutical active compound in the powder mixtures intended to the direct tabletting...
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Luminescent properties of Ln3+ doped tellurite glasses containing AlF3
PublikacjaThe low-phonon energy tellurite glasses TeO2-BaO-Bi2O3 and TeO2-BaO-Bi2O3-AlF3 triply doped with Eu3+, Tb3+, Tm3+ ions in two different molar ratios were synthesized using melt-quenching technique. Their structure and luminescence properties were widely investigated by X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and Photoluminescence Spectroscopy (PL). The luminescence...
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Electrochemical impedance spectra and CV curves of V2O5 nanocrystals
Dane BadawczeThe DataSet contains the EIS spectra for coin-cells and CV curves with the V2O5 nanocrystals obtained by the sol-gel method. Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) were measured using the AUTOLAB 302N potentiostat-galvanostat under Nova software. The EIS measurements were recorded in the frequency range 100 kHz to 10 mHz...
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Electrochemical impedance spectra and CV curves of V2O5 nanorods
Dane BadawczeThe DataSet contains the EIS spectra for coin-cells and CV curves with the V2O5 nanorods obtained by the sol-gel method. Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) were measured using the AUTOLAB 302N potentiostat-galvanostat under Nova software. The EIS measurements were recorded in the frequency range 100 kHz to 10 mHz for...
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The luminescence study of Sr2−xSrxPN3:Eu2+ nitridophosphate.
Dane BadawczeIn this work, a series of Ca2−xSrxPN3:Eu2+ nitridophosphate phosphors through a solid-solution strategy involving a hot isostatic press was developed by collaborators from National Taiwan University. Unexpected dual emissions in the red and infrared regions are observed, different from previous research results. The unique change in red and near-infrared...
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Chromium Cluster Luminescence: Advancing Near‐Infrared Light‐Emitting Diode Design for Next‐Generation Broadband Compact Light Sources
Dane BadawczeIn modern technology devices, an energy-saving miniature near-infrared (NIR) light source plays a critical role in non-destructive, non-invasive sensing applications and further advancement of technology. This dataset reports the broadband NIR luminescence of Cr3+ clusters for designing phosphor-converted NIR light-emitting diodes as an alternative...
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Spectroscopic evaluation on pseudopolymorphs of sodium naproxen
PublikacjaThis paper demonstrates the assessment of vibrational spectroscopy methods such as middle infrared, near infrared and Raman spectroscopy (FTIR, FT-NIR, Raman) for the identification of pseudopolymorphic forms of a model active pharmaceutical ingredient (API) - sodium naproxen (NpxNa). NpxNa, in the form of three different pseudopolymorphs, was investigated by methods dedicated for solid state characterization: DSC (differential...
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Optimization of boron-doping process of titania nanotubes via electrochemical method toward enhanced photoactivity
PublikacjaIn this work, we were focused on the development of the electrochemical approach resulting in a stable boron doping of titania nanotubes. The doping procedure concerns anodic polarization of as-anodized titania in a H3BO3 solution acting as n boron precursor. The series of attempts were taken in order to elaborate the most beneficial doping conditions. The parameters of electrochemical doping allowing to obtain boron-doped titania...
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The effect of PEDOT morphology on hexavalent chromium reduction over 2D TiO2/PEDOT photocatalyst under UV–vis light
PublikacjaThe present study represents an approach to apply organic-inorganic hybrid materials for photocatalytic removal of heavy metals from the aqueous environment. The photocatalytic activity of the semiconductor modified with the conjugated polymer may depends on the conjugated polymer type, its amount and morphology. Therefore, in the present study the effect of poly (3, 4-ethylenedioxythiophene) (PEDOT) morphology on adsorption and photoreduction...
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Solid State Conductivity of Optimized Polypyrrole Coatings on Iron Obtained from Aqueous Sodium Salicylate Solution Determined by Impedance Spectroscopy
PublikacjaIn this work the optimization procedure for corrosion resistance, surface analysis and electrical properties of PPy-Fe electrodes have been examined. Polypyrrole (PPy) film was electrochemically synthesized in a one step process from an aqueous solution of sodium salicylate and pyrrole with certain concentrations, different parameters and type of polymerization...
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Novel Class of Proton Conducting Materials—High Entropy Oxides
PublikacjaHere, for the first time, we present data on proton conductivity of high-entropy, single-phase perovskites. The BaZr0.2Sn0.2Ti0.2Hf0.2Ce0.2O3−δ, BaZr0.2Sn0.2Ti0.2Hf0.2Y0.2O3−δ, BaZr1/7Sn1/7Ti1/7Hf1/7Ce1/7Nb1/7Y1/7O3−δ, and BaZr0.15Sn0.15Ti0.15Hf0.15Ce0.15Nb0.15Y0.10O3−δ single-phase perovskites were synthesized. Before electrical measurements, materials were characterized using X-ray diffraction (XRD), scanning electron microscopy...
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Effect of cobalt addition on the corrosion behaviorof near equiatomic NiTi shape memory alloy in normal saline solution: electrochemical and XPS studies
PublikacjaThe electrochemical and corrosion (uniform and localized) behavior of a binary Ni52Ti48 shape memory alloy (SMA) and two ternary Ni52Ti48-xCox (x = 1.5 and 4.0 wt.%) SMAs were studied. Measurements were conducted in 0.9% NaCl solution at 37 oC employing various electrochemical methods. These include: linear polarization resistance (LPR), linear sweep voltammetry (LSV), chronoamperometry and dynamic electrochemical impedance spectroscopy...
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Role of MnO in manganese–borate binary glass systems: a study on structure and thermal properties
PublikacjaStructural and thermal properties of x MnO−(100−x)B2O3 (where x=40, 50 and 60 mol%) glass samples have been investigated with the employment of various techniques. Fourier transform infrared spectroscopy results revealed the influence of MnO on glass matrix. Decrease of B–O bond-related band intensities has been observed. MnO addition was found to introduce broken [BO2O−]n chains. Differential scanning calorimetry (DSC) measurements...
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Synthesis, thermal, structural and electrical properties of vanadium-doped lithium-manganese-borate glass and nanocomposites
PublikacjaA glassy sample with a nominal formula LiMn1−3x/2VxBO3 (where x = 0.05) was synthesised using the melt-quenching method. Material was characterised by differential thermal analysis (DTA), X-ray diffactometry (XRD) at room temperature and as a function of temperature (HT-XRD), X-ray photoelectron spectroscopy (XPS), impedance spectroscopy (IS) and scanning electron microscopy (SEM). Dependences of glass transition and crystallisation...
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Investigation of the structural and thermal properties of aluminum-rich Ca–Al–Si–O–N glasses
PublikacjaIn this paper, we investigate the structure and thermal properties of aluminum-rich transparent Ca–Al–Si–O–N glasses. The obtained glasses were prepared by a traditional melt-quenching technique at 1650 °C using AlN as the nitrogen source. The obtained glasses have a nAl/nSi>1 and contain up to 17 eq.% of N. The structure of the glasses was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, infrared, and Raman...
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PROBLEMS WITH CORROSION PROTECTION STEEL STACKS IN FGD SYSTEMS
PublikacjaThis paper presents problems associated with corrosion of steel stacks and changes in philosophy of corrosion protection when implemented into flue gas desulphurization systems. In-situ tests were taken by means of electrochemical impedance spectroscopy at a stack which discharges flue gas before wet lime/limestone desulphurization. A very rapid soaking of spherical infill vinylester coating with electrolyte has been observed....
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Dynamic Nanoimpedance Characterization of the Atomic Force Microscope Tip-Surface Contact
PublikacjaNanoimpedance measurements, using the dynamic impedance spectroscopy technique, were carried out during loading and unloading force of a probe on three kinds of materials of different resistivity. These materials were: gold, boron-doped diamond, and AISI 304 stainless steel. Changes of impedance spectra versus applied force were registered and differences in the tip-to-sample contact character on each material were revealed. To...
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Raman spectroscopy analysis of poly(lactic acid)-carbon black composite treated by femtosecond laser
Dane BadawczeThe dataset contains the Raman spectroscopy measurements of commercially available carbon black-filled poly(lactic acid) 3D printed electrodes after femtosecond laser ablation. These results were utilized in the manuscript published in Electrochimica Acta: 10.1016/j.electacta.2022.140288
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Simulation-Based Design of Microstrip Linear Antenna Arrays Using Fast Radiation Response Surrogates
PublikacjaFast yet accurate technique for simulation-based design of linear arrays of microstrip patch antennas is presented. Our technique includes: (i) optimization of the corrected array factor of the antenna array under design for a phase excitation taper resulting in reduced side lobes; (ii) simulation-driven optimization of the array element for element dimensions resulting in matching at and about operational frequency, and (iii)...
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Application of the discrete Green's function-based antenna simulations for excitation of the total-field/scattered-field interface in the FDTD method
PublikacjaIn this article, the discrete Green's function formulation of the finite-difference time-domain (DGF-FDTD) method is proposed for simulation of wire antennas irradiating inhomogeneous dielectric scatterers. Surface equivalence theorem in the discrete domain is used to separate the problem into an inhomogeneous domain and a wire antenna that are simulated with the use of FDTD and DGF-FDTD, respectively. Then, the excitation of the...
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Influence of plasmon resonance on the luminescence of titanium dioxide thin films doped with rare earth ions
PublikacjaIn this work the study of the optical properties of europium doped titanium dioxide thin films (TiO2:Eu) enhanced by gold plasmonic nanostructures are presented. Plasmonic platforms were manufactured by thermal annealing of thin film of Au, deposited on a Corning glass substrate. As a result of thermal treatment, gold spherical nanostructures with average dimensions of 50 nm were obtained. Luminescent TiO2:Eu film was deposited...
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Detection of Denatonium Benzoate (Bitrex) Remnants in Noncommercial Alcoholic Beverages by Raman Spectroscopy
PublikacjaIllegal alcoholic beverages are often introduced into market using cheap technical alcohol, which is contaminated by denatonium benzoate (Bitrex) of very small concentration. Bitrex is the most bitter chemical compound and has to be removed before alcohol consumption. The home-made methods utilize sodium hypochlorite to disintegrate particles of denatonium benzoate in alcohol and to remove bitter taste before trading. In this experimental...
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INFLUENCE OF BISMUTH CONTENT ON COMPLEX IMMITTANCE CHARACTERISTICS OF PRESSURELESS SINTERED BiNbO4 CERAMICS
PublikacjaGoal of the present research was to study immittance properties of BiNbO4 ceramics fabricated by the solid state reaction route followed by pressureless sintering. Four sets of samples were examined, namely the one fabricated from the stoichiometric mixture of oxides, viz. Bi2O3 and Nb2O5 as well as the ones with an excess of 3%, 5% and 10% by mole of Bi2O3. The immittance properties were studied by impedance spectroscopy. Measurements...
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Interactions between hydration spheres of two different solutes in solution: The least squares fitting with constraints as a tool to determine water properties in ternary systems
PublikacjaBiological systems are complex and the problem of their description lies in mutual interactions between their components. This paper is focused on model experiment-based studies which can reduce these difficulties. The ternary aqueous N-methylacetamide (NMA)–Na2HPO4 system has been studied by means of the FTIR spectroscopy. A novel difference spectra method aimed to extract the spectral contribution of water affected simultaneously...
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Two kinds of oxygen vacancies in lithium titaniate doped with copper as detected by EPR
PublikacjaLithium titanate (Li1+xTi2-xO4) doped with Cu2+ ions was synthesized by sol-gel processing method. The structure and morphology are characterized by X-ray Diffraction (XRD), X-ray Photoemission Spectroscopy (XPS), Scanning Electron Microscopy (SEM) and Electron Paramagnetic Resonance (EPR). Spin Hamiltonian parameters describing Zeeman and hyperfine interaction for 63Cu2+ ions were obtained from EPR spectra simulations. The spectra...
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Możliwości wykorzystania spektroskopii fotoelektronów w analizie jakości środowiska wodnego
PublikacjaSpektroskopia fotoelektronów w zakresie promieniowania X, (XPS, z ang. X-ray photoelectron spectroscopy) jest nowoczesną metodą analityczną wykorzystywaną w wielu wiodących ośrodkach naukowych na świecie. Jest ona stale ulepszana, jak też poznawane są nowe obszary jej zastosowania. W niniejszym artykule przedstawione zostały możliwości wykorzystania metody XPS w ramach obszarów badawczych powiązanych z gospodarką wodną, takich...
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ZnO-decorated green-synthesized multi-doped carbon dots from Chlorella pyrenoidosa for sustainable photocatalytic carbamazepine degradation
PublikacjaThe promising green synthesis of carbon dots (CDs) from microalga Chlorella pyrenoidosa was achieved using simple hydrothermal and microwave-assisted methods. Doping of nanomaterials by nonmetals (N, S, and P) was confirmed by X-ray photoelectron spectroscopy (XPS), while the existence of metals in the CDs was confirmed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and transmission electron microscopy (TEM),...
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Photocatalytic activity of solvothermal prepared BiOClBr with imidazolium ionic liquids as a halogen sources in cytostatic drugs removal
PublikacjaIn this work, the BiOClBr, as a new family of bismuth based semiconductors, was successfully applied to remove of cytostatic drugs from water under UV-Vis light irradiation. BiOCl, BiOBr and BiOClBr were synthesized using two steps solvothermal method in glycerol. The inorganic salts (KCl and KBr) and 1-butyl-3-metylimidazolium chloride (BmimCl) and 1-butyl-3-metylimidazolium bromide (BmimBr) ionic liquids (ILs) were used as the...
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Optimization of electrochemical doping approach resulting in highly photoactive iodine-doped titania nanotubes
PublikacjaThe paper focuses on the optimization procedure concerning the synthesis method resulting in highly ordered titania nanotubes doped with iodine atoms. The doping process was based on the electrochemical treatment of a titania nanotube layer immersed in a potassium iodide (KI) solution acting as an iodine precursor. A number of endeavors were undertaken in order to optimize the doping conditions. Electrolyte concentration, reaction...
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Novel application of dynamic electrochemical impedance monitoring to a cataphoretic coating process
PublikacjaThe paper presents a novel method of on-line impedance monitoring of cataphoretic coating application process. Utilization of dynamic electrochemical impedance spectroscopy (DEIS) overcame the fundamental problem connected with non-stationarity of the aforementioned coating deposition process, which eliminates classical impedance spectroscopy technique from a real-time description of cataphoresis. The paper illustrates selected examples...
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Optical method supported by machine learning for dynamics of C‐reactive protein concentrations changes detection in biological matrix samples
PublikacjaIn this article we present the novel spectroscopy method supported with machine learning for real-time detection of infectious agents in wastewater. In the case of infectious diseases, wastewater monitoring can be used to detect the presence of inflammation biomarkers, such as the proposed C-reactive protein, for monitoring inflammatory conditions and mass screening during epidemics for early detection in communities of concern,...
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Structural investigations of niobium-doped bioactive calcium-phosphate glass-ceramics by means of spectroscopic studies
PublikacjaSynthetic calcium-phosphate based glasses and glass-ceramics play a crucial role in the development of tissue engineering. These materials have a high biocompatibility with biological analogues, excellent ability to undergo varying degrees of resorbability and due to their non-toxicity and relatively high bioactivity they are commonly used as bone and dental implants. A substantial research effort is devoted to improve synthetic...
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Optical and photocatalytic properties of rare earth metal-modified ZnO quantum dots
PublikacjaA series of novel ZnO quantum dots modified with rare earth metals was successfully prepared by a simple sol-gel approach. The effects of types (Eu, Er, Tb, Yb, Ho, La) and amounts (from 0.09 to 0.45 mmol) of lanthanides on the optical properties, structural characterization and photocatalytic activity of ZnO/RE QDs were systematically investigated. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform...
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Imidazolium silanethiolates relevant to the active site of cysteineproteases. A cooperative effect in a chain of NH(+)...S(-) hydrogenbonds
PublikacjaThree imidazolium silanethiolates relevant to the active site of cysteine proteases have been synthesized and investigated by X-ray diffraction, IR spectroscopy and computational methods. As indicated by crystallographic and FT-IR data in the solid state, the transfer of proton from thiol to imidazole takes place and a thiolato-imidazolium ion pair is formed. The FT-IR spectra of crystalline imidazolium silanethiolates exhibit...
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Enhanced visible light photocatalytic activity of Pt/I-TiO2 in a slurry system and supported on glass packing
PublikacjaHighly photoactive I/TiO2, Pt/I-TiO2 nanocomposites were obtained using a hydrothermal and wet impregnation method. The incorporation of iodine and modification with 0.05 mol% of platinum leads to enhanced photocatalytic activity as compared to singly doped TiO2 due to the presence of impurity energy level in the structure of TiO2. X-ray diffraction, TEM microscopy, UV–Vis spectroscopy, X-ray photoelectron spectroscopy and BET...
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Impact of strontium non-stoichiometry of SrxTi0.3Fe0.7O3-δ on structural, electrical, and electrochemical properties for potential oxygen electrode of intermediate temperature solid oxide cells
PublikacjaThis work presents the results of a comprehensive study on the impact of the A-site non-stoichiometry of SrxTi0.3Fe0.7O3-δ (x = 0.90, 0.95, 1.00, 1.05) ceramics on their physicochemical properties. The materials were fabricated by the conventional solid-state reaction method and their structure was determined by X-ray diffractometry, X-ray photoelectron spectroscopy and electron microscopy. Their sintering and thermal expansion...