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Charge transfer and formation of complexes in the He+ collisions with the furan molecules
PublikacjaCharge transfer and formation of the collision complexes have been studied experimentally in fragmentation of the furan molecules in collisions with He+ cations. The excited atomic and diatomic fragments of furan have been identified using collision-induced luminescence spectroscopy. Charge transfer ionization of the furan molecules has been observed in production of helium atoms in the excited 1s4d 1D2, 3D1,2,3 states. The fragmentation...
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Chromogenic macrocyclic derivatives of azoles - synthesis and properties,
PublikacjaNew azocrown ethers comprising imidazoles in the macrocycle have been synthesized. Imidazole, 2-methyl-, 4-methyl-, and 4-phenylimidazole were incorporated to form macrocyclic units by coupling with the appropriate bis-diazonium salts. The syntheseswere performed under high dilution conditions. The X-ray structure of a water adduct of the 21-membered crown ether derivative of 4-methylimidazole 8 has been solved. Metal...
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Azomacrocyclic derivatives of imidazole: synthesis, structure, and metal ion complexation properties
PublikacjaNew azocrown ethers comprising imidazoles in the macrocycle have been synthesized. Imidazole, 2-methyl-, 4-methyl-, and 4-phenylimidazole were incorporated to form macrocyclic units by coupling with the appropriate bis-diazonium salts. The syntheseswere performed under high dilution conditions. The X-ray structure of a water adduct of the 21-membered crown ether derivative of 4-methylimidazole 8 has been solved. Metal...
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Instantaneous Impedance Analysis of Non-Stationary Corrosion Process: a Case Study of Carbon Steel in 1M HCl
PublikacjaThe paper concerns the problem of evaluation of stationarity of carbon steel corrosion in 1M HCl. Comparison of corrosion rate with addition of corrosion inhibitor to the reference measurement is the most often used way of evaluating inhibitor efficiency. Such an approach is valid only if corrosion rate is a stationary process. Two complementary techniques were used simultaneously: volumetric analysis of evolved hydrogen and instantaneous...
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IR and Raman study of oxy-nitride glasses
PublikacjaVarious silicate and phosphate glasses with and without nitride addition were structurally characterized by IR and Raman spectroscopy. The studied glass systems include Na-Ca-P-O-N (1), AE-Si-O-N (with AE=Mg, Ca, Sr, Ba)(2), La-Si-O-N (3) as well as the Na-(Li)-Be-O-(N) (4,5) system. The samples were prepared by different techniques such as remelting of pre-prepared glass samples of the oxide systems with Mg and/or Si3N4 powders...
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NANOCRYSTALLINE CATHODES FOR SOLID OXIDE FUEL CELLS MADE OF NOBLE METALS
PublikacjaCathodes for solid oxide fuel cells prepared by the infiltration method at 600 °C are presented. The infiltration method allows to produce stable, nanostructured electrodes. Cathodes were prepared using gold, platinum, La2NiO4+δ (L2N) and La0.6Sr0.4Co0.2Fe0.8O3 δ (LSCF). Symmetrical cathode/electrolyte/cathode samples were prepared and examined with SEM microscopy and electrochemical impedance spectroscopy. Despite successful deposition...
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Implementation of DEIS for reliable fault monitoring and detection in PEMFC single cells and stacks
PublikacjaDynamic Electrochemical Impedance Spectroscopy (DEIS) was presented as novel method for diagnostic and monitoring of PEMFC stack and single cells operation. Impedance characteristics were obtained simultaneously with current - voltage characteristics for stack and each individual cell. Impedance measurements were performed in galvanodynamic mode. It allowed to compare performance of each cell and identification of faulty cell operation...
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Electrochemical investigations on the corrosion behaviour of reinforcing steel in diatomite- and zeolite-containing concrete exposed to sulphuric acid
PublikacjaCorrosion is a major concern for most structural applications. Its detrimental effect significantly reduces the life of metallic components. This paper presents the results of an experimental investigation of corrosion in the steel reinforcement of concrete samples having three different substituents: 20% diatomite, 20% zeolite, and a reference without zeolite or diatomite. All concrete specimens were subjected to a solution of...
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Cross sections for ionization and ionic fragmentation of pyrimidine molecules by electron collisions
PublikacjaThe electron impact mass spectroscopy and the total ion collection measurements were used to investigate the ionization and ionic fragmentation of the pyrimidine, C4H4N2, molecules in the gasphase. The cation mass spectra were measured in the 10−85 amu range and the observed mass peaks assigned to corresponding ionic fragments. The most abundant cation in the mass spectra is the parent cation, C4H4N+2, at 80 amu. The appearance...
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Fe local structure in Pt-free nitrogen-modified carbon based electrocatalysts: XAFS study
PublikacjaThe paper presents a new results on the bonding environment (coordination number and geometry) and on oxidation states of Fe in nitrogen-modified Fe/C composites used as Pt-free catalysts for oxygen reduction in Direct Hydrogen Fuel Cells. Starting from glucose or fructose, two catalysts displaying different electrochemical performance were prepared and studied in the form of pristine powder and thin catalytic layer of electrode...
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Synthesis and characterization of mononuclear Zn(II), Co(II) and Ni(II) complexes containing a sterically demanding silanethiolate ligand derived from tris(2,6-diisopropylphenoxy)silanethiol
PublikacjaFour heteroleptic complexes of zinc(II), cobalt(II) and nickel(II) containing a monodentate silanethiolate ligand derived from tris(2,6-diisopropylphenoxy)silanethiol (TDST), were prepared and characterized. The geometries of ligands in the complexes are typical: distorted tetrahedral in zinc and cobalt(II) complexes and square planar in nickel(II) compound. Magnetic studies performed for Ni(II) and Co(II) compounds confirm the...
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Hydrogen migration in formation of NH(A3Π) radicals via superexcited states in photodissociation of isoxazole molecules
PublikacjaFormation of the excited NH(A 3Π) free radicals in the photodissociation of isoxazole (C3H3NO) molecules has been studied over the 14-22 eV energy range using photon-induced fluorescence spectroscopy. The NH(A 3Π) is produced through excitation of the isoxazole molecules into higher-lying superexcited states. Observation of the NH radical, which is not a structural unit of the isoxazole molecule, corroborates the hydrogen atom...
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Formation of CN (B2∑+) radicals in the vacuum-ultraviolet photodissociation of pyridine and pyrimidine molecules
PublikacjaFormation of the excited CN(B2∑+) free radicals in the photodissociation of pyridine (C5H5N) and pyrimidine (C4H4N2) molecules was investigated over the energy ranges 16–27 and 14.7–25 eV, respectively. Photon-induced fluorescence spectroscopy was applied to detect the vibrationally and rotationally excited CN radicals by recording the B2∑+→X2∑+ emission bands (violet system). The measured dissociation yield curves demonstrate...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part I. On-line gas analyzers
PublikacjaThe paper reviews the subject literature concerning the analytical instruments routinely used for monitoring volatile organic compounds in atmospheric air. The analyzers are classified as stationary or mobile according to their ease of transport. Stationary DOAS (Differential Optical Absorption Spectroscopy) analyzer is characterized, as are MIMS (Membrane Introduction Mass Spectrometry), MESI (Membrane Extraction with Sorbent...
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Oxygen biosensor based on carbon nanotubes directly grown on graphitic substrate
PublikacjaFilms of carbon nanotubes were synthesized on the graphitic substrates by CVD method in the presence of catalyst. Two different catalysts were used, that is nickel and iron, supported on graphitic substrates. The as-obtained nanotubes were analyzed by SEM imaging with EDX and Raman spectroscopy. The results revealed their multi-walled morphology. Free radical reaction was carried out in order to chemically functionalize synthesized...
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Functional phase bistability in a nanocrystalline RbMn[Fe(CN)6] thin film fabricated by matrix-assisted laser evaporation
PublikacjaOne of the main barriers hindering applications of Prussian blue metal assemblies is their poor processability, which makes the fabrication of intact thin films very difficult. In this work, a nanocrystalline RbMn[Fe(CN)6]·xH2O film on silicon substrate was obtained for the first time via laser-stimulated deposition and investigated. Temperature-induced phase transition and bistability within broad hysteresis loop (120 K), along...
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Electrical conductivity of nanostructured acceptor-doped ceria fabricated by spark plasma sintering (SPS)
PublikacjaHigh purity nanoscale powders (~10–15 nm size) of two different compositions of ceria, doped with Gd3+ and Ca2+, have been consolidated by spark plasma sintering (SPS) at different temperatures. Fully-dense samples were observed only at a sintering temperature of 980 °C. The as-sintered samples showed rather fast grain growth with an average grain size below 300 nm. The electrical properties of the samples were evaluated by impedance...
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Evaluation of Praseodymium and Gadolinium Doped Ceria as a Possible Barrier Layer Material for Solid Oxide Cells
PublikacjaIn this work, nanocrystalline layers based on the Pr, Gd co-doped CeO2 were investigated. For the preparation of thin layers, lowtemperature spray pyrolysis technique was used. Different stoichiometries of the layers were produced for comparison on polished sapphire substrates. The microstructure of the prepared thin layers was studied by scanning electron microscopy (SEM), energydispersive X-ray spectroscopy (EDS) and X-ray diffractometry (XRD)....
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Terbium Substituted Lanthanum Orthoniobate: Electrical and Structural Properties
PublikacjaThe results of electrical conductivity studies, structural measurements and thermogravimetric analysis of La1−xTbxNbO4+δ (x = 0.00, 0.05, 0.1, 0.15, 0.2, 0.3) are presented and discussed. The phase transition temperatures, measured by high-temperature x-ray diffraction, were 480 °C, 500 °C, and 530 °C for La0.9Tb0.1NbO4+δ, La0.8Tb0.2NbO4+δ, and La0.7Tb0.3NbO4+δ, respectively. The impedance spectroscopy results suggest mixed conductivity...
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Electron impact ionization and cationic fragmentation of the pyridazine molecules
PublikacjaElectron impact mass spectroscopy was used to investigate ionization and cationic fragmentation of the pyridazine (1,2 diazine), C4H4N2, molecules in the gas phase. The mass spectra were measured and the observed mass peaks assigned to the corresponding cations. The appearance energies of most of the cationic fragments were determined and the possible fragmentation processes are discussed. The total cross section for electron...
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Obtaining of coumarone-indene resins based on light fraction of coal tar 2. Coumarone-indene resins with epoxy groups
PublikacjaCoumarone-indene resins (CIR) with carboxy groups were synthesized via cooligomerization of unsaturated compounds presented in light fraction of coal tar and its fraction boiling out within 423–463 K with the addition of such industrial monomers as styrene, maleic anhydride, glycidyl methacrylate and methacrylic acid. 2,2`-Azobis(2-methylpropionitrile) in the form of 0.2 M solution in toluene was used as an initiator. The effect...
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PHOTON LUMINESCENCE STUDIES OF TETRAHYDROFURAN FOLLOWING TRIHYDROGEN CATIONS IMPACT IN THE 20–1000 EV ENERGY RANGE
PublikacjaPhoton emission arising during tetrahydrofuran (C4H8O, THF) fragmentation initiated by H3 + ion impact has been studied experimentally. Luminescence fragmentation spectra and the relative emission cross-sections of the excited fragments have been measured using collision-induced emission spectroscopy in the 20–1000 eV energy range. The main features in the spectra are the H Balmer series lines, whose intensities decrease with increasing...
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Preparation and characterization of bis‐phosphonated polycarbohydrates
PublikacjaA simple, cost-effective, one-pot method was proposed to introduce bis-phosphonic groups onto alginic acid and carboxymethyl cellulose (CMC). New derivatives were characterized by means of nuclear magnetic resonance, X-ray photoelectron, and attenuated total reflectance Fourier transform infrared spectroscopy. These analyses confirmed the successful transformation of carboxylic groups present in alginic acid and CMC into bis-phosphonic...
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Transformation of bimetallic Ag–Cu thin films into plasmonically active composite nanostructures
PublikacjaFormation of plasmonically active silver, copper and composite silver-copper nanostructures were studied in this paper. Metallic nanostructures were fabricated by thermal disintegration, so called dewetting, of the thin films in an argon atmosphere. The formation process of the nanostructures was in-situ observed by a novel method, based on resistance measurements. The influence of the material and thickness of the initial thin...
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Application of analytical methods for the determination of bioactive compounds in some berries
PublikacjaFluorometry, ESI-MS, FTIR, and radical scavenging assays were used for characterization of bioactive compounds and the levels of their antioxidant activities. Polyphenols, flavonoids, anthocyanins, and ascorbic acid and the level of antioxidant activity of water extracts of “Murtilla-like” [Myrteola nummularia (Poiret) Berg.], and other widely consumed berries were determined and compared. The contents of bioactive compounds and...
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Solvothermal synthesis and structural characterization of three polyoxotitanium-organic acid clusters
PublikacjaThree new titanium oxo-clusters Ti4O2(OiPr)10(OOCPhMe)2 (I), Ti6O4(OEt)8(OOCPhMe)8 (II) and Ti6O6(OEt)6(OOCCHPh2)6 (III) were obtained by easy one-step solvothermal reactions of titanium(IV) isopropoxide, alcohols and carboxylic acids. The three compounds were characterized by single-crystal and powder X-ray diffraction, TGA/DSC, optical and electron microscopy, and FTIR and NMR spectroscopy. X-ray powder diffraction and spectroscopy...
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Highly antifouling polymer-nanoparticle-nanoparticle/polymer hybrid membranes
PublikacjaWe introduce highly antifouling Polymer-Nanoparticle-Nanoparticle/Polymer (PNNP) hybrid membranes as multi-functional materials for versatile purification of wastewater. Nitrogen-rich polyethylenimine (PEI)-functionalized halloysite nanotube (HNT-SiO2-PEI) nanoparticles were developed and embedded in polyvinyl chloride (PVC) membranes for protein and dye filtration. Bulk and surface characteristics of the resulting HNT-SiO2-PEI...
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Pulsed Laser Deposition of Bismuth Vanadate Thin Films—The Effect of Oxygen Pressure on the Morphology, Composition, and Photoelectrochemical Performance
PublikacjaThin layers of bismuth vanadate were deposited using the pulsed laser deposition technique on commercially available FTO (fluorine-doped tin oxide) substrates. Films were sputtered from a sintered, monoclinic BiVO4 pellet, acting as the target, under various oxygen pressures (from 0.1 to 2 mbar), while the laser beam was perpendicular to the target surface and parallel to the FTO substrate. The oxygen pressure strongly affects...
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Temperature-controlled nanomosaics of AuCu bimetallic structure towards smart light management
PublikacjaGold–copper nanostructures are promising in solar-driven processes because of their optical, photocatalytic and photoelectrochemical properties, especially those which result from the synergy between the two metals. Increasing interest in their internal structure, such as the composition or distribution of the Au and Cu as well as the size and shape of the nanoparticles, have developed to define their physicochemical properties. In...
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Conversion of waste biomass into activated carbon and evaluation of environmental consequences using life cycle assessment
PublikacjaIn this article, activated carbon was produced from Lantana camara and olive trees by H3PO4 chemical activation. The prepared activated carbons were analyzed by characterizations such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer–Emmett–Teller, X-ray diffraction, thermogravimetric analysis, and Fourier transform infrared spectroscopy. H3PO4 is used as an activator agent to create an abundant pore...
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SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF NIOBIUM-DOPED HYDROXYAPATITE CERAMICS
PublikacjaHydroxyapatite (HAp) ceramic materials are considered as one of the most promising implant materials in bone surgery and in dentistry. They exhibit unique biocompatibility, bioactivity, and osteoconductivity, which are the most desirable biomaterial features. However, HAp itself is brittle, has low strength, high degree of crystallinity and low solubility at physiological pH. Doping synthetic HAp with metal ions plays an important...
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Synthesis, physicochemical and theoretical studies on new rhodium and ruthenium dimers. Relationship between structure and cytotoxic activity
PublikacjaTwo dimeric compounds of the general formulae (Et3NH)2[Rh2(μ2-L)4Cl2] (1) (where L = thiophene-2-carboxylate) and [((η6-p-cymene)Ru)2(μ-Cl)3]PF6 (2) have been synthesized using a new method. The unique anionic complex 1 (space group P bca) has octahedral coordination in which the equatorial positions are occupied by the oxygen atoms of four thiophene-2-carboxylates in a paddle wheel fashion. In complex 2 (space group ), each Ru(II)...
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Electrochemical detection of bacterial endotoxin lipopolysaccharide (LPS) on gold electrode modified with DAL-PEG-DK5-PEG-OH - Antimicrobial peptide conjugate
PublikacjaThis work describes fabrication of gold electrodes modified with peptide conjugate DAL-PEG-DK5-PEG-OH that enables ultra-sensitive detection of lipopolysaccharide (LPS) isolated from the reference strain of Escherichia coli O26:B6. The initial step of the established procedure implies immobilization of the fully protected DAL-PEG-DK5-PEG-OH peptide on the surface of the gold electrode previously modified by cysteamine. Then side...
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Magnetic anisotropy and structural flexibility in the f ield-induced single ion magnets [Co{(OPPh2) (EPPh2)N}2], E = S, Se, explored by experimental and computational methods
PublikacjaDuring the last few years, a large number of mononuclear Co(II) complexes of various coordination geometries have been explored as potential single ion magnets (SIMs). In the work presented herein, the Co(II) S = 3/2 tetrahedral [Co{(OPPh2)(EPPh2)N}2], E = S, Se, complexes (abbreviated as CoO2E2), bearing chalcogenated mixed donor-atom imidodiphosphinato ligands, were studied by both experimental and computational techniques. Specifically,...
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The adiabatic potentials of low-lying electronic states of the NaRb molecule
PublikacjaAdiabatic potential energy curves and spectroscopic constants have been calculated for the NaRb molecule. The results of ten states of the symmetry Σ+, six states of the symmetry Π, and two states of the symmetry Δ are obtained by the nonrelativistic quantum chemical method used with pseudopotentials describing the interaction of valence electrons with atomic cores. Analysis is based on a comparison with the results of other theoretical...
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Graphene Oxide as Mine of Knowledge: Using Graphene Oxide To Teach Undergraduate Students Core Chemistry and Nanotechnology Concepts
PublikacjaThe aim of this laboratory experiment is to utilize graphene oxide (GO) material to introduce under-graduate students to many well-known concepts of general chemistry. GO is a new nanomaterial that has generated worldwide interest and can be easily produced in every well-equipped undergraduate chemical laboratory. An in-depth examination of GO synthesis, as well as a study of its structure and properties, allows students to familiarize...
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Molecular dynamics studies of polyurethane nanocomposite hydrogels
PublikacjaPolyurethane PEO-based hydrogels have a broad range of biomedical applicability. They are attractive for drug-controlled delivery systems, surgical implants and wound healing dressings. In this study, a PEO based polyurethane hydrogels containing Cloisite R 30B, an organically modified clay mineral, was synthesized. Structure of nanocomposite hydrogels was determined using XRD technique. Its molecular dynamics was studied by means...
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A XAS study of a highly diluted Pt electrocatalyst operating in PEM fuel cells
PublikacjaWe present an X-ray absorption spectroscopy (XAS) study of a low Pt content catalyst layer(Pt loading 0.1 mg c2) operating at the cathode of a proton exchange membrane fuel cell(PEMFC). This catalyst is based on the use of a mesoporous inorganic matrix as a support forthe catalyst Pt nanoparticles. Due to the high Pt dilution, in situ measurements of itsstructural properties by XAS are challenging and suitable experimental strategies...
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Charge-assisted N(+)–H···(−)S hydrogen bonds in the crystal structure of selected diammonium thiophenolates.
PublikacjaNew salts of thiophenol with three flexible aliphatic diamines H2N(CH2)nNH2 (n = 2, 4 and 6) have been synthesized and characterized by elemental analyses, IR spectroscopy and X-ray crystallography in order to analyze their supramolecular architecture. Structural analyses indicate that in the crystals, proton transfer has occurred, with the –SH group giving (+)N–H···S(−) hydrogen bonding interaction. The structure of compound 1...
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Materiał węglowy ptrzymany na bazie karbonizowanego chitozanu domieszkowanego platyną = CARBON MATERIAL RECEIVED THROUGH CARBONIZATION OF CHITOSAN DOPED WITH PLATINUM
PublikacjaThe aim of this work was to investigate the impact of porous carbons with high nitrogen content onthe platinum catalyst performance properties. The system may be applied as well as cathodic catalyst for oxygenreduction in microbial fuel cells.We report a simple route for preparation of dispersed Platinum on the carbon support. Chitosan powder wasprotonated using aqueous solution of organic acid. The water from the pores was removed...
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Electronic states of tetrahydrofuran molecules studied by electron collisions
PublikacjaElectronic states of tetrahydrofuran molecules were studied in the excitation energy range 5.5-10 eV using the technique of electron energy loss spectroscopy in the gas phase. Excitation from the two conformations, C2 and Cs, of the ground state of the molecule are observed in the measured energy loss spectra. The vertical excitation energies of the 3(no3s) triplet state from the C2 and Cs conformations of the ground state of the...
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Elimination and migration of hydrogen in the vacuum-ultraviolet photodissociation of pyridine molecules
PublikacjaElimination of the excited hydrogen atoms H(n), n = 4–7, and hydrogen migration in formation of the excited NH(A 3Π) free radicals in the photodissociation of pyridine, C5H5N, molecules have been studied over the 17.5–70 eV photon energy range. In the measurements the photon-induced fluorescence spectroscopy technique has been applied. Both fragments are produced through excitation of pyridine molecules into higher-lying superexcited...
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Visualizing spatially decomposed intermolecular correlations in the infrared spectra of aprotic liquids
PublikacjaInfrared (IR) spectroscopy is commonly used to study intermolecular interactions in the liquid phase, including solvation phenomena. On the other hand, ab initio molecular dynamics (AIMD) simulations offer the possibility to obtain IR spectra from first principles. Surpassing the experiment, AIMD simulations can deliver additional information on the spatial intermolecular correlations underlying the IR spectrum of the liquid. Although...
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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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OBTAINING OF COUMARONE-INDENE RESINS BASED ON LIGHT FRACTION OF COAL TAR 3. COUMARONE-INDENE RESINS WITH METHACRYLIC FRAGMENTS
PublikacjaThe method for obtaining coumarone-indene resins with methacrylic fragments (CIRM) was developed with the addition of methyl ethacrylate, using a light fraction of coal tar and its fraction boiling within 423–463 К. CIRM was obtained via radical cooligomerization using 2,2'-azobis (2-methyl-propionitrile) as the initiator. The effect of the initiator amount, temperature and reaction time on the yield, softening temperature and...
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Synergistic Effects of Bitumen Plasticization and Microwave Treatment on Short-Term Devulcanization of Ground Tire Rubber
PublikacjaGround tire rubber (GTR) was mechano-chemically modified with road bitumen 160/220 and subsequently treated using a microwave radiation. The combined impact of bitumen 160/220 content and microwave treatment on short-term devulcanization of GTR was studied by thermal camera, wavelength dispersive X-ray fluorescence spectrometry (WD-XRF), static headspace, and gas chromatography-mass spectrometry (SHS-GC-MS), thermogravimetric analysis...
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Nanocrystalline Polymer Impregnated [Fe(pz)Pt(CN)4] Thin Films Prepared by Matrix-Assisted Pulsed Laser Evaporation
PublikacjaIn this work, the fabrication of [Fe(pz)Pt(CN)4] (pz = pyrazine) thin films by means of matrix-assisted pulsed laser evaporation (MAPLE) was investigated. As starting material, a cryogenically cooled suspension of anocrystalline [Fe(pz)Pt- (CN)4] (0.35wt.-%) in a mixture of 1,1-dichloroethane and polyethylene glycol (PEG) was used. Films of a thickness up to 150–200 nm were deposited on Si substrates by laser ablation at λ = 1064...
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Influence of Phase Composition on Dielectric Properties of Bismuth-Based Ceramics with Scheelite-Type Structure
PublikacjaGoal of the present research was to study dielectric properties of BiNbO4 ceramics fabricated by solid state reaction route followed with pressureless sintering. The samples were fabricated from the mixture of oxides, viz. Nb2O5 and Bi2O3. Apart from stoichiometric amount an excess of 3%, 5% and 10% by mole of Bi2O3 was used. It was found that an excess amount of Bi2O3 oxide caused formation of Bi5Nb3O15 minor phase in amount of...
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Structure and optical parameters of Eu doped tellurium oxide thin films prepared by reactive magnetron sputtering method
PublikacjaIn this work the structural properties and photoluminescence of tellurium dioxide thin films doped by europium were described. Thin films were deposited by magnetron sputtering method and simultaneously heated at 200 °C. Presence of Eu ions and their valence states was confirmed by X-ray photoemission spectroscopy measurements. The structure of the films as well as the influence of europium dopant on crystalline structure of the...
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The Impact of Crushed Rock Spoil on Pitting Corrosion of Selected Stainless Steel
PublikacjaThe paper presents the results of the pitting resistance investigations of selected stainless steels in the chloride environment and the simultaneous impact of erosive factors using the cyclic polarization technique. Additionally, using electrochemical techniques, ie: electrochemical impedance spectroscopy (EIS) and measurement of corrosion potential, the behavior of the passive layer of selected stainless steels in the environment...