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High-conducting Bi4V2-xFexO11-δ ceramics containing Fe2O3 nanocrystals: Structure and properties
PublicationThe topography, structure, thermal, magnetic, and electrical properties of Bi4V2-xFexO11-δ ceramics substituted with x = 0.5 and 0.7 Fe were studied. The microscope analysis showed the presence of iron-rich nanocrystals formed on the Bi-Fe-V-O grains. The X-ray diffraction studies confirmed that grains are built mostly of tetragonal Bi4V1.5Fe0.5O10.5 phase. Thermal properties analysis showed an order-disorder type γ ↔ γʹ phase...
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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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Mechanism of Osmolyte Stabilization–Destabilization of Proteins: Experimental Evidence
PublicationIn this work, we investigated the influence of stabilizing (N,N,N-trimethylglycine) and destabilizing (urea) osmolytes on the hydration spheres of biomacromolecules in folded forms (trpzip-1 peptide and hen egg white lysozyme─hewl) and unfolded protein models (glycine─GLY and N-methylglycine─NMG) by means of infrared spectroscopy. GLY and NMG were clearly limited as minimal models for unfolded proteins and should be treated with...
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Evaluation of the Cathodic Electrodeposition Effectiveness of the Hydroxyapatite Layer Used in Surface Modification of Ti6Al4V-Based Biomaterials
PublicationThe important issue associated with the design and the fabrication of the titanium and titanium alloy implants is the increase of their biointegration with bone tissue. In the presented paper, the research results concerning the conditions used in the cathodic deposition of hydroxyapatite on the surface Ti6Al4V substrates primarily modified by the production of TiO2 nanoporous coatings, TiO2 nanofibers, and titanate coatings, are...
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Influence of reactive oxygen species during deposition of iron oxide films by high power impulse magnetron sputtering.
PublicationIron oxide films were deposited using high power impulse magnetron sputtering (HiPIMS) of an iron cathode in an argon/oxygen gas mixture at different gas pressures (0.5~Pa, 1.5~Pa, and 5.0~Pa). The HiPIMS system was operated at a repetition frequency $f = 100$~Hz with a duty cycle of 1~\%. A main goal is a comparison of film growth during conventional and electron cyclotron wave resonance-assisted HiPIMS. The deposition plasma...
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Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublicationThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
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Scaling Up the Process of Titanium Dioxide Nanotube Synthesis and Its Effect on Photoelectrochemical Properties
PublicationIn this work, for the first time, the influence of scaling up the process of titanium dioxide nanotube (TiO2NT) synthesis on the photoelectrochemical properties of TiO2 nanotubes is presented. Titanium dioxide nanotubes were obtained on substrates of various sizes: 2 × 2, 4 × 4, 5 × 5, 6 × 6, and 8 × 8 cm2. The electrode material was characterized using scanning electron microscopy as well as Raman and UV–vis spectroscopy in order...
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Mechanical Behavior of Bi-Layer and Dispersion Coatings Composed of Several Nanostructures on Ti Substrate
PublicationThree coatings suitable for biomedical applications, including the dispersion coating composed of multi-wall carbon nanotubes (MWCNTs), MWCNTs/TiO2 bi-layer coating, and MWCNTs-Cu dispersion coating, were fabricated by electrophoretic deposition (EPD) on Ti Grade II substrate. Optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and nanoindentation were applied to study topography, chemical, and...
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Aqueous solutions of NMA, Na2HPO4 , and NaH2PO4 as models for interaction studies in phosphate–protein systems
PublicationPhosphate buffers are essential for many areas of studies. However, their influence on buffered systems is often ignored. The phosphate salts can interact with biologically important macromolecules (e.g. proteins) and stabilize or destabilize them. With our research, we want to answer question what kind of interactions, if any, occur between phosphate ions and a protein backbone model — N-methylacetamide (NMA). ATR-FTIR spectroscopy...
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Gas Composition Influence on the Properties of Boron-Doped Diamond Films Deposited on the Fused Silica
PublicationThe main subject of this study are molecular structures and optical properties of boron-doped diamond films with [B]/[C] ppm ratio between 1000 and 10 000, fabricated in two molar ratios of CH 4 -H 2 mixture (1 % and 4 %). Boron-doped diamond (BDD) film on the fused silica was presented as a conductive coating for optical and electronic purposes. The scanning electron microscopy images showed homogenous and polycrystalline surface...
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Copper(II) complexes of 7-amino-2-methylchromone and 7-aminoflavone: Magneto-structural, spectroscopic and DFT characterization
PublicationFour new complexes of copper(II) consisting of two different chromone derivatives with carbonyl and amine donor atoms: 7-aminoflavone (L1) and 7-amino-2-methylchromone (L2), were synthesized and characterized by X-ray diffraction, UV–Vis, FT-IR, EPR spectroscopy, MS and elemental analysis. In all four compounds, the chromone derivatives were found to act as monodentate O- or N-ligands. The structural characteristics of 1a and...
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Syntheses, Structures and Reactivity of Terminal Phosphido Complexes of Iron(II) Supported by a β-Diketiminato Ligand
PublicationWe report the synthesis of the first series of terminal phosphido iron complexes supported by a β‐diketiminato ligand (Dippnacnac) and their catalytic activity in dehydrocoupling of secondary phosphines. Anionic and neutral mono‐ or diphosphido complexes were obtained from the reaction of [(Dippnacnac)FeCl2Li(dme)2] with the R2PLi (R = iPr, tBu, Cy, Ph) phosphides by tuning the stoichiometric ratio, polarity of the solvent, and...
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Investigation of functional layers of solid oxide fuel cell anodes for synthetic biogas reforming
PublicationSolid 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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Interactions in Ternary Aqueous Solutions of NMA and Osmolytes—PARAFAC Decomposition of FTIR Spectra Series
PublicationIntermolecular interactions in aqueous solutions are crucial for virtually all processes in living cells. ATR-FTIR spectroscopy is a technique that allows changes caused by many types of such interactions to be registered; however, binary solutions are sometimes difficult to solve in these terms, while ternary solutions are even more difficult. Here, we present a method of data pretreatment that facilitates the use of the Parallel...
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Improvement of opipramol base solubility by complexation with β-cyclodextrin
PublicationOpipramol (OPI), a tricyclic antidepressant and anxiolytic compound, is administered orally in the form of a dihydrochloride. Salt form of the drug has a higher solubility in water and hence bioavailability and stability. A similar effect can be achieved by closing the hydrophobic part of the drug molecule in the cyclodextrin cavity. The paper presents opipramol inclusion complexes with beta-cyclodextrin (β-CD) in 1:1 molar ratio....
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High temperature oxidation behavior of SUS430 SOFC interconnects with Mn-Co spinel coating in air
PublicationIn this study, SUS430 alloy is evaluated for its high temperature corrosion properties as a possible material for interconnects of solid oxide fuel cells (SOFCs). Samples are coated with Mn-Co by commercial physical vapor deposition (PVD) process and oxidized in air for 1250 h at 800 °C. A dense cubic Mn-Co-Fe spinel layer is formed on the surface, showing great effect on corrosion reduction compared with the samples without coating....
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Physico‐Mechanical Properties and Flammability of PUR/PIR Foams Containing Expandable Graphite Core‐Shell Composite Particles
PublicationIn this work, polyurethane/polyisocyanurate (PUR/PIR) foams were modified by two types of expandable graphite (EG) core-shell composite particles. The pulverized EG core-shell composite particles were prepared during emulsion polymerization using methyl methacrylate or glycidyl methacrylate for the synthesis of the polymeric shells (poly(methyl methacrylate) (PMMA) and poly (glycidyl methacrylate) (PGMA)), and then the obtained EG_PMMA...
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INFLUENCE OF BISMUTH CONTENT ON COMPLEX IMMITTANCE CHARACTERISTICS OF PRESSURELESS SINTERED BiNbO4 CERAMICS
PublicationGoal 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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Nuclear Magnetic Resonance Metabolomics Reveals Qualitative and Quantitative Differences in the Composition of Human Breast Milk and Milk Formulas
PublicationCommercial formula milk (FM) constitutes the best alternative to fulfill the nutritional requirements of infants when breastfeeding is precluded. Here, we present the comparative study of polar metabolite composition of human breast milk (HBM) and seven different brands of FM by nuclear magnetic resonance spectroscopy. The results of the multivariate data analysis exposed qualitative and quantitative differences between HBM and...
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Two kinds of oxygen vacancies in lithium titaniate doped with copper as detected by EPR
PublicationLithium 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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Reclaimed Rubber/Poly(ε‐caprolactone) Blends: Structure, Mechanical, and Thermal Properties
PublicationThe amount of elastomeric waste, especially from tires is constantly increasing on a global scale. The recycling of these residua should be considered a priority. Compounding the waste rubbers with other polymers can be an excellent alternative to reuse waste materials. This procedure requires solving the issue of the lack of compatibility between the waste rubber particles and other polymers. Simultaneously, there is a claim for...
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Fast-response optoelectronic detection of explosives’ residues from the nitroaromatic compounds detonation: field studies approach
PublicationWe are presenting an application of optoelectronic nitrogen dioxide (NO2) analyzer based on cavity enhanced absorption spectroscopy in the detection of traces of explosives after detonation. It has been shown that the analyzer using blue-violet laser is able to detect explosive residues after the detonation of various amounts of nitroaromatic compounds (75g-1kg) with higher efficiency than the HPLC soil sample testing equipment,...
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Mono- and bimetallic (Pt/Cu) titanium(IV) oxide photocatalysts. Physicochemical and photocatalytic data of magnetic nanocomposites’ shell
PublicationSurface modification of titania with noble and semi-noble metals resulted in significant enhancement of photocatalytic activity. Presented data, showing the photocatalytic properties of TiO2-M (where M is Pt and/or Cu) photocatalysts were further used as Fe3O4@SiO2/TiO2-M magnetic nanocomposites shells in "Mono- and bimetallic (Pt/Cu) titanium(IV) oxide core-shell photocatalysts with Vis light activity and magnetic separability"...
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Laser induced formation of copper species over TiO2 nanotubes towards enhanced water splitting performance
PublicationWe proposed fast and scalable route where the ordered TiO2 nanotubes coated with thin copper layers were annealed by the laser beam of 355 nm wavelength at different fluencies in the range of 15–120 mJ/cm2. As a result, copper species are integrated with the titania substrate and the formed material exhibits unique optical absorption bands in the visible range. Moreover, X-ray photoelectron spectroscopy analysis reveals the formation...
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Novel fast non-linear electrochemical impedance method for corrosion investigations
PublicationThe paper presents a novel approach to corrosion rate monitoring using non-linear electrochemical impedance spectroscopy. The authors propose a new variant of non-linear impedance measurement using amplitude-modulated multi-frequency ac perturbation signal. It allows shortening of measurement duration so it is possible to monitor corrosion rate of the systems experiencing rapid changes. In this way a limitation resulting from lack...
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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
PublicationBiological 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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Insights into Compatibilization of Poly(ε-caprolactone)-based Biocomposites with Diisocyanates as Modifiers of Cellulose Fillers
PublicationThis study aimed to analyze the impact of cellulose fillers’ modification with diisocyanates on the performance of composites based on the poly(ε-caprolactone) (PCL) matrix. Four most commonly used diisocyantes (isophorone, hexamethylene, toluene, and methylene diphenyl) were applied as modifiers of cellulose fillers (5 and 15 wt% per mass of filler). Modified fillers were introduced in the amount of 30 wt% into the PCL matrix....
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Precipitation of Spherical Vaterite Particles via Carbonation Route in the Bubble Column and the Gas-Lift Reactor
PublicationSpherical vaterite particles were produced by carbonation of calcium chloride solution with addition of ammonia to facilitate CO2 absorption. Synthesis of calcium carbonate was carried out in a bubble column or gas-lift reactor. The course of the reaction was monitored by pH measurements. Precipitated solids were analyzed by Fourier-transformed infrared spectroscopy, x-ray powder diffraction and scanning electron microscopy, and...
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Impedance Measurement and Selection of Electrochemical Equivalent Circuit of a Working PEM Fuel Cell Cathode
PublicationThe dynamic impedance analysis of direct methanolfuel cell (DMFC) cathode supplied with pure oxygen is pre-sented. Presented results were obtained during dynamic chang-es of the current density in working fuel cell. Investigation ofthe occurring processes at cathode was carried with dynamicelectrochemical impedance spectroscopy (DEIS). A discussionwas conducted based on the determined correlation parameterχ2. It was shown that...
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Electrochemical investigations on corosivity of de-icing liquids for railway infrastructure
PublicationThe paper presents the results of electrochemical tests of the de-icing fluid for railway infrastructure. DC and AC electrochemical tests were performed to determine the corrosion rates of structural steel, cast iron and aluminium in the newly produced fluid. The results were compared with the corrosion rates of the same materials in the fluid without corrosion inhibitors. The obtained test results indicate a low corrosion risk...
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Improvements and new functionalities of UNRES server for coarse-grained modeling of protein structure, dynamics, and interactions
PublicationIn this paper we report the improvements and extensions of the UNRES server (https://unres-server.chem.ug.edu.pl) for physics-based simulations with the coarse-grained UNRES model of polypeptide chains. The improvements include the replacement of the old code with the recently optimized one and adding the recent scale-consistent variant of the UNRES force field, which performs better in the modeling of proteins with the β and the...
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Electrocatalytic oxidation of methanol, ethylene glycol and glycerine in alkaline media on TiO2 nanotubes decorated with AuCu nanoparticles for an application in fuel cells
PublicationIn this work, we present the catalytic and photocatalytic activity of AuCu nanostructures obtained on TiO2 nanotubes toward methanol, ethylene glycol and glycerine oxidation. The electrode material is prepared by anodization of Ti foil, thin AuCu layer sputtering and rapid thermal treatment under argon atmosphere. Scanning electron microscopy images confirmed the presence of ordered tubular architecture of TiO2 as well as nanoparticles...
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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
PublicationIn 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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Mechanism of hopping conduction in Be–Fe–Al–Te–O semiconducting glasses and glass–ceramics
PublicationElectrical properties of beryllium-alumino-tellurite glasses and glass–ceramics doped with iron ions were studied using impedance spectroscopy. The conductivity was measured over a wide frequency range from 10 mHz to 1 MHz and the temperature range from 213 to 473 K. The D.C. conductivity values showed a correlation with the Fe-ion concentration and ratio of iron ions on different valence states in the samples. On the basis of...
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Properties of some fruit wines
PublicationRecently wereported about theconsumption of redwines fromgrapes, havingseveral health properties. Thereare different types of wines that originated fromgrapesand other fruits. In the present study fruit wines frompersimmon, kiwifruit and pomegranatewereinvestigated and compared for theirantioxidant ability, usingcupricion reducingantioxidant capacity (CUPRAC)and the 2,2-diphenyl-1-picrylhydrazyl (DPPH)assays. To thefruit wines...
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Nanocrystallization as a tool for controlling in vitro dissolution of borophosphate glass
PublicationThe controlled nanocrystallization of sodium-calcium-borophosphate glass (Na16.6Ca5.1B10.5Al0.8P10.5 O56.5 in at %) was conducted to investigate its influence on in vitro dissolution. Three temperatures (570 ◦C, 590 ◦C, and 610 ◦C) were selected based on thermal analysis and investigation of the morphology, structure, and in vitro dissolution of glass and glass-ceramics was conducted. The results of X-ray diffraction confirmed...
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Effect of Laser Treatment on Intrinsic Mechanical Stresses in Titanium and Some of Its Alloys
PublicationLaser surface treatment conducted at different power levels is an option to modify titanium bone implants to produce nano- and microtopography. However, such processing can lead to excess mechanical stress within the surface layer. This research aims to calculate the level of such residual stresses after the surface processing of Ti grade IV, Ti15Mo, and Ti6Al7Nb alloys with an Nd:YAG laser. Light and scanning electron microscopies...
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The Effect of C45 Carbon Black-Phosphomolybdic Acid Nanocomposite on Hydrogenation and Corrosion Resistance of La2Ni9Co Hydrogen Storage Alloy
PublicationIn this paper, we analysed the influence of corrosion processes and the addition of a carbon black-heteropoly phosphomolybdic acid (C45-MPA) nanocomposite on the operating parameters of a hydride electrode obtained on the basis of the intermetallic compound La2Ni9Co. The electrochemical properties of negative electrodes for NiMH batteries were studied using galvanostatic charge/discharge curves, the potentiostatic method, and electrochemical...
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Development of biocompatible iron oxide-silicon oxide core-shell nanoparticles as subcellular delivery platform for glucosamine-6-phosphate synthase inhibitors
PublicationIn order to develop the preparation of iron oxide-silica coreshell nanoparticles (CSNPs), thesis deeply explores the cetyltrimethylammonium (CTA+) directed silica coating methods of the oleic-acid capped iron oxide nanoparticles (OA-IONPs) initialized under near-neutral pH conditions. It is demonstrated that the initial alkaline hydrolysis of ethyl acetate in the presence of CTA+ and OA-IONPs induces an unusual ligand exchange...
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Spectroscopic studies on physicochemical properties of selected unsymmetrical bisacridine derivatives and NMR analysis of their interactions with the model sequence Pu22 aided by molecular dynamics
PublicationIn recent years, new promising acridine derivatives have appeared, belonging to the unsymmetrical bisacridines (UAs) family with high anticancer activity. Both their physicochemical properties and their mechanism of action at the molecular level have not been thoroughly analyzed so far. Four derivatives were selected for the study, termed as: C-2028, C-2041, C-2045 and C-2053. The first aim of this work was to determine the protonation...
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Reactive deposition of TiNx layers in a DC-magnetron discharge
PublicationTiNx layers have been deposited in 'balanced mode' and 'unbalanced mode' of a reactive DC-magnetron plasma (carrier gas argon, reactive gas nitrogen) under different conditions. Discharge power and reactive gas flow have been varied. The layers have been examined by X-ray photoelectron spectroscopy (XPS), X-ray reflectometry (XR), and spectroscopic ellipsometry (SE). The results of the layer analyses were combined with plasma investigations...
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In vitro antioxidative and binding properties of phenolics in traditional, citrus and exotic fruits
PublicationMany polyphenols bind proteins, therefore our research was focused on the potential of protein binding to polyphenols of investigated fruits and their health-related effects. The contents of polyphenols and related antioxidant activities of traditional, citrus and exotic fruits were compared. The presence of polyphenols (flavonoids and phenolic acids) in the investigated samples and their interaction with human serum albumin (HSA)...
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Solid-contact lead(II) ion-selective electrodes for potentiometric determination of lead(II) in presence of high concentrations of Na(I), Cu(II), Cd(II), Zn(II), Ca(II) and Mg(II)
PublicationLead and its compounds are a serious threat to the environment. Monitoring of this toxic heavy metal is a driving force for the continuous development of novel lead(II) ionophores to be applied in ion-selective electrodes. In this work a highly selective lead(II) ionophore, namely 25,26,27,28-tetrakis(piperidinylthiocarbonylmethylene)-p-tert-butylcalix[4]arene, was used in solid-contact ion-selective electrodes for determination...
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Modification of thermal and rheological characteristics of bitumen by waste PET/GTR blends
PublicationWaste poly(ethylene terephthalate) (wPET)/ground tire rubber (GTR) blends with variable compositions were applied as low-cost modifiers into bitumen and their performance has been evaluated via morphological, thermal and rheological analyses. Depending on the weight ratio of wPET/GTR, dispersion of single/composite domains of waste polymers in the bitumen has promoted the interaction between bitumen and blend components. Fourier...
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Softwood-lignin/natural rubber composites containing novel plasticizing agent: Preparation and characterization
PublicationComposite materials based on natural rubber were obtained by using glycerolysate (decomposition prod- uct of polyurethane) as a novel plasticizer. In order to determine the effect of various lignin content, four different filler amounts were used, namely, 5 phr (parts per 100 parts of natural rubber) of lignin (WLI5G), 10 phr (WLI10G), 20 phr (WLI20G), and 40 phr (WLI40G). The reference specimen without lignin (WLI0G) was also...
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An investigation on the role of GMA grafting degree on the efficiency of PET/PP-g-GMA reactive blending: morphology and mechanical properties
PublicationGlycidyl methacrylate (GMA) has been grafted on polypropylene (PP) with the aid of styrene (St) comonomer, by changing dicumyl peroxide initiator content, GMA level, and St concentration. The performance of the resulting PP-g-GMA reactive material towards static and dynamic mechanical properties of poly (ethylene terephthalate) (PET) was monitored in terms of grafting reaction variables and compatibilizer content. Fourier transform...
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To what extent can hyperelastic models make sense the effect of clay surface treatment on the mechanical properties of elastomeric nanocomposites?
PublicationThe poor knowledge about nonlinear mechanical behavior of elastomer nanocomposites arises from the incomplete information on the interface. Application of hyperelastic models provides more insights into the nature and the situation of interaction between the elastomeric matrix and nanofillers. The current work seeks to address the effect of interphase strength on tensile properties of the elastomer nanocomposites under large deformations....
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Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH4/H2/N2 plasma enhanced chemical vapor deposition
PublicationThe influence of N2 concentration (1%–8%) in CH4/H2/N2 plasma on structure and optical properties of nitrogen doped diamond (NDD) films was investigated. Thickness, roughness, and optical properties of the NDD films in the VIS–NIR range were investigated on the silicon substrates using spectroscopic ellipsometry. The samples exhibited relatively high refractive index (2.6 6 0.25 at 550 nm) and extinction coefficient (0.05 6 0.02...
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The Effect of Calcination Temperature on Structure and Photocatalytic Properties of WO3/TiO2 Nanocomposites
PublicationSeries ofWO3/TiO2 nanocompositeswere obtained by hydrothermal method followed by calcination in the temperature range from 400∘C to 900∘C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900∘C resulted in change of photocatalytic activity under UV-Vis light.Moreover,...
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π-Stacking attraction vs. electrostatic repulsion: competing supramolecular interactions in a tpphz-bridged Ru(ii)/Au(iii) complex
PublicationThe synthesis and characterization of a mixed metal ruthenium(II)/gold(III) complex bridged by tetrapyridophenazine (tpphz) are described. It is isostructural and isoelectronic to the well-known photocatalysts with palladium(II) or platinum(II). Concentration dependent 1H-NMR spectroscopy and XRD studies show that the electrostatic repulsion between the gold(III) moieties exceeds the attractive π-stacking interaction. Theoretical...