Search results for: UV-Vis/DR spectra
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Azomacrocyclic derivatives of imidazole: synthesis, structure, and metal ion complexation properties
PublicationNew 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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Electrochemically Induced Synthesis of Triphenylamine-based Polyhydrazones
PublicationTriphenylamine-based hydrazones were subjected to electropolymerization process that gave well conductive hydrazone based polymers. The first example of polyhydrazone formation during the electrochemical process was shown. The estimation of polymer structure was demonstrated using IR spectroelectrochemistry. The EPR spectroelectrochemistry allowed to explain why in some cases dimer couldn’t be formed. The results of electrochemical,...
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Structure and Stability Characterization of Natural Lake Pigments Made from Plant Extracts and Their Potential Application in Polymer Composites for Packaging Materials
PublicationNatural dyes were extracted from various plant sources and converted into lake pigments based on aluminum and tin. Three different plants (weld, Persian berries, and Brazilwood) were chosen as representative sources of natural dyes. High-performance liquid chromatography (HPLC) and triple-quadrupole mass spectrometry (QqQ MS) were used to identify dyestuffs in the raw extracts. The natural dyes and lake pigments were further characterized...
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Kontrola procesu wytwarzania biowodoru z gliceryny podczas fermentacji beztlenowej
PublicationProdukcja wodoru z biomasy z wykorzystaniem procesów biologicznych jest korzystną ekonomicznie alternatywą w porównaniu do otrzymywania wodoru np. na drodze zgazowania, pirolizy, czy przez rozkład biomasy w warunkach nadkrytycznych. Wśród biologicznych procesów otrzymywania wodoru, za najbardziej obiecującą uważa się ciemną fermentację wodorową, w której substraty organiczne są przekształcane bez udziału światła przez bakterie...
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Thioacetamide and thiourea impact on visible light activity of TiO2
PublicationAktywne w świetle widzialnym fotokatalizatory na bazie tlenku tytanu (IV) przygotowano w wyniku hydrolizy izopropylanu tytanu (IV) z tioacetamidem i tiomocznikiem oraz kalcynacji w temperaturze 450ºC. Wyniki badań wskazują, że fenol i 4-chlorofenol były efektywnie degradowane w obecności domieszkowanego TiO2 oraz światła widzialnego (λ>400 nm). Głównym celem badań było zbadanie wpływu ilość zastosowanego prekursora domieszki...
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UAV spectrometer reflectance and leaf area index for vegetation near Gdynia, Poland
Open Research DataReflectance data from the UAV flights with UV-VIS spectrometer along with leaf area index measurements for vegetaion near Gdynia, Poland.
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Cation sensing by diphenyl-azobenzocrowns
PublicationMetal cations complexation and proton binding by 13- and 16-membered diphenyl-azobenzocrowns and diphenyl-hydroxyazobenzocrowns were studied in acetonitrile using spectroscopic methods: UV–vis spectroscopy, spectrofluorimetry, and 1H NMR spectroscopy. Phenyl moieties in benzene rings were found to affect binding strength alkali and alkaline earth metal cations and hydrogen ion, and affect tautomeric equilibrium of hydroxyazobenzocrowns....
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Transformation of bimetallic Ag–Cu thin films into plasmonically active composite nanostructures
PublicationFormation 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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Efficient Method for the Concentration Determination of Fmoc Groups Incorporated in the Core-Shell Materials by Fmoc–Glycine
PublicationIn this paper, we described the synthesis procedure of TiO2@SiO2 core-shell modified with 3-(aminopropyl)trimethoxysilane (APTMS). The chemical attachment of Fmoc–glycine (Fmoc–Gly–OH) at the surface of the core-shell structure was performed to determine the amount of active amino groups on the basis of the amount of Fmoc group calculation. We characterized nanostructures using various methods: transmission electron microscope...
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Synthesis, physicochemical and theoretical studies on new rhodium and ruthenium dimers. Relationship between structure and cytotoxic activity
PublicationTwo 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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Preparation and characterization of Pt–N/TiO2 photocatalysts and their efficiency in degradation of recalcitrant chemicals
PublicationSeries of Pt–N/TiO2 photocatalysts were synthesized using the sol–gel method. The photocatalysts’ characteristics by X-ray diffractometry (XRD), scanning transmission electron microscopy (STEM), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) showed that sample with the molar ratio Ti:N equal 1:4 and platinum nanoparticles size of about 3 nm had anatase structure, about 94 m2/g specific surface area...
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Raman data of deuterium and hydrogen grown boron-doped diamond
Open Research DataRaman spectra were recorded at room temperature using a micro-Raman spectrometer (Invia, Renishaw) equipped with an edge filter with different excitation wavelengths and lasers: UV λ = 325 nm (HeCd), blue λ = 488 nm (Ar+), green λ = 514 nm (Ar+), and IR λ = 785 nm (IR diode) and 50× microscope objective. To avoid sample heating, the radiation power...
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Role of nitrogen in optical and electrical band gaps of hydrogenated/hydrogen free carbon nitride film
PublicationWe report the optical and electrical band gap energy of amorphous hydrogenated carbon nitride (a-HCNx) and carbon nitride (a-CNx) as a function of nitrogen concentration (N/C). The optical band gap of a-HCNx and a-CNx films has been determined by means of Ellipsometry and UV-VIS. Both optical and electrical band gaps increase with elevated nitrogen concentration. Experimentally obtained electrical band gap is compared with the...
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Photodegradation of lauric acid at an anatase single crystal surface studied by atomic force microscopy
PublicationBadania obejmowały obserwację zmian topografii powierzchni, za pomocą mikroskopii sił atomowych, cienkiej warstwy kwasu laurynowego osadzonego na monokrysztale anatazu. Warstwę kwasu laurynowego o grubości 80-90 nm naświetlano promieniowaniem z zakresu UV-Vis. Zauważono, że kwas laurynowy osadzany metodą wirującego dysku tworzy na powierzchni monokryształów TiO2 struktury domenowe. Stwierdzono, że podczas naświetlania nie ulega...
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Complexes of manganese(II) tri-tert-butoxysilanethiolate with chelating N-donor ligands.
PublicationTri-tert-butoksysilanotiolan manganu(II) jest związkiem wrażliwym i rozkładającym się w warunkach atmosferycznych. Z tego względu synteza jego pochodnych z chelatującymi zasadami heterocyklicznymi takimi jak 1,10-fenantrolinaza czy 2,2'-bipirydyl wydawał się dogodną metodą otrzymania bardziej stabilnych układów. Otrzymane w ten sposób krystaliczne proszki wykazują znacznie wyższą stabilność temperaturową, możliwe jest więc przechowywanie...
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Fluorescence of p-hydroxyazobenzocrowns – Tautomeric equilibrium effect
PublicationThe spectroscopic properties of a series of para-hydroxyazobenzocrowns, including three novel compounds, were investigated using UV–Vis absorption and emission spectroscopy. This study presents, for the first time, determined quantum yield (QY) values for macrocycles of this category, ranging between 0.122 and 0.195. The highest values were obtained for crowns bearing two phenyl substituents in benzene rings. The impact of aromatic...
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The effect of microemulsion composition on the morphology of Pd nanoparticles deposited at the surface of TiO2 and photoactivity of Pd-TiO2
PublicationA series of microemulsion (ME) system, constituted by different water to surfactant molar ratios (Wo) and oil to surfactant mass ratios (S), have been applied for Pd-TiO2 preparation. The effect of ME properties on the morphology of Pd nanoparticles formed at TiO2 surface and an effect of Pd size and distribution on the surface and photocatalytic properties of Pd-TiO2 were investigated. Microemulsion systems were characterized...
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Visible light photocatalysis employing TiO2/SrTiO3-BiOI composites: Surface properties and photoexcitation mechanism
PublicationA series of binary TiO2/SrTiO3 and ternary TiO2/SrTiO3_BiOI composites have been synthesized using multistep preparation method. Characterization of the obtained photocatalysts covered complex analysis including morphology + y (SEM), BET specific surface area, porosity, optical properties (DRS), chemical composition of surface (XPS), crystal structure and crystal size (XRD). UV–vis and Vis ligh induced photocatalytic activity was...
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Preparation and photocatalytic activity of iron-modified titanium dioxide photocatalysts
PublicationTiO2 modyfikowany żelazem otrzymano dwiema metodami: metodą zol-żel oraz metodą impregnacji powierzchniowej. Fotokatalizatory kalcynowano w temperaturze 400C. Jako matrycę TiO2 zastosowano komercyjnie dostępne proszki ditlenku tytanu: P25 (Evonik, Niemcy, 50m2/g) oraz ST-01 (Ishihara Sangyo, Japonia, 300m2/g). Charakterystyka otrzymanych fotokatalizatorów obejmowała wyznaczenie właściwości absorpcyjnych, powierzchni właściwej BET...
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Carbon dioxide photoconversion. The effect of titanium dioxide immobilization conditions and photocatalyst type.
PublicationBadanie efektywności procesu fotokonwersji CO2 prowadzono w fazie gazowej w obecności promieniowania UV-Vis, pary wodnej oraz fotokatalizatorów. Zbadano wpływ wybranych parametrów tj. masa, temperatura i czas suszenia fotokatalizatora oraz rodzaj nośnika na efektywność procesu fotokonwersji. Wyznaczono optymalne parametry prowadzenia procesu oraz przedstawiono wstępne wyniki badań w obecności fotokatalizatorów modyfikowanych nanoczastkami...
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Preparation of silver nanoparticles with controlled particle size
PublicationNanocząstki srebra wykazują zdolność absorpcji promieniowania widzialnego, która jest efektem istnienia powierzchniowego plazmonu. W zależności od kształtu i wielkości cząstek obserwuje się różną barwę koloidów srebra. W wyniku przeprowadzonych badań otrzymano nanocząstki srebra metodą chemicznej redukcji. Zaobserwowano wpływ rodzaju reduktora (kwas askorbinowy, borowodorek sodu), stabilizatora (PVP, PVA) oraz prekursora srebra...
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Tri-tert-butoksysilanotiolanowe kompleksy cynku(II), kadmu(II) i kobaltu(II) jako modele koordynacji jonu cynku w miejscu aktywnym dehydrogenazy alkoholowej i niektórych innych enzymów
PublicationDehydrogenaza alkoholowa (ADH) katalizuje odwracalne utlenienie alkoholi do aldehydów przy użyciu NAD+ co można podsumować równaniem:R1R2CHOH + NAD+ = R1R2CO + NADH + H+. Geometria koordynacyjna cynku w miejscu aktywnym ADH opisywana jest na ogół jako tetraedryczna jednak istnieją również przesłanki wskazujące na poszerzanie sfery koordynacyjnej metalu w cyklu katalitycznym do LK=5. W pracy przeglądowej opisano badania nad syntetycznymi,...
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New heterometallic Co/Zn, Ag/Co, and Ag/Zn imidazolates: structural characterization and catalytic activity in the oxidation of organic compounds
PublicationNanocrystalline powders of monometallic and bimetallic imidazolates of Co, Zn, and Ag were produced by a reaction carried out in water. The powders were characterized by powder X-ray diffraction and the crystal structures of new compounds Ag2ZnIm4 and Ag2CoIm4 (Im = imidazolate) were solved. Heterometallic Co/Zn imidazolates showed the standard ZIF-8 crystal structure while Ag/Zn and Ag/Co systems were isostructural with the copper...
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Non-toxic fluorine-doped TiO2 nanocrystals from TiOF2 for facet-dependent naproxen degradation
PublicationIn the present study, the photocatalytic degradation of naproxen (NPX), which is a nonsteroidal anti-inflammatory drug (NSAID), frequently detected in drinking water, was investigated. The F-doped TiO2 with defined morphology was successfully obtained from TiOF2 and applied for photocatalytic degradation under UV-vis and visible light. All samples were characterised by X-ray diffraction, scanning electron microscopy, X-ray photoelectron...
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Micro-cracking pattern recognition of hybrid CNTs/GNPs cement pastes under three-point bending loading using acoustic emission technique
PublicationThe generation of microcracks has an important influence on the behaviour of concrete structures. In this study, the acoustic emission (AE) technique was used to investigate the fracture phenomena and micro-cracking behavior of hybrid carbon nanotubes (CNTs, the 1-D allotrope of carbon atoms) and graphene nanoplatelets (GNPs, 2D monolayer of sp2-hybridized carbon atoms), cement composites under three-point bending loading. In...
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Procedura przygotowania próbki do oznaczania wielopierścieniowych węglowodorów aromatycznych w produktach technicznych
PublicationW pracy opisano nową metodę przygotowania próbki w celu oznaczania śladowych zawartości wielopierścieniowych węglowodorów aromatycznych (WWA) w wysokowrzących produktach naftowych. Wartości granicy oznaczalności dla badanych WWA w materiałach tego typu mieściły się w przedziale od kilkudziesięciu ng/kg do poniżej dwudziestu ug/kg. Badania wykazały, że w celu oddzielenia większości zanieczyszczeń od analitów, bez ich znaczących...
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Fabrication of ILs-Assisted AgTaO3 Nanoparticles for the Water Splitting Reaction: The Effect of ILs on Morphology and Photoactivity
PublicationThe design of an active, stable and ecient photocatalyst that is able to be used for hydrogen production is of great interest nowadays. Therefore, four methods of AgTaO3 perovskite synthesis, such as hydrothermal, solvothermal, sol-gel and solid state reactions, were proposed in this study to identify the one with the highest hydrogen generation eciency by the water splitting reaction. The comprehensive results clearly show that...
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Glutathione conjugation of the antitumor-active 1-nitroacridine derivatives compounds C-857 and C-1748 – the major role of glutathione S-transferase M1-1
Open Research DataObjectives: C-857 and C-1748 are antitumor-active agents, monomers of unsymmetrical bisacridine derivatives. The aim of this study was to analyze their glutathione (GSH) conjugation in vitro in the presence of glutathione S-transferase (GST) M1-1.
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Fabrication and photoactivity of organic-inorganic systems based on titania nanotubes and PEDOT containing redox centres formed by different Prussian Blue analogues
PublicationHerein, the heterojunction composed of an inorganic substrate: ordered hydrogenated titania nanotubes (H-TiO2NTs) and a deposited organic film: poly(3,4-ethylenedioxythiophene) (PEDOT) is reported. The conducting polymer is modified with different transition metal haxacyanoferrates (Mehcf), wherein as metal: copper, iron, cobalt and nickel are introduced. The presence of various metal centres provides characteristic redox activity...
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Influence of temperature and interactions with ligands on dissociation of dsDNA and ligand-dsDNA complexes of various types of binding : an electrochemical study.
PublicationSeveral medicinally important compounds that bind to dsDNA strands via intercalation (C-1311, C-1305, EtBr), major groove binding (Hoechst 33258) and covalent binding (cis-Pt) were examined. The obtained results suggest that both the transfer of conformation B to C and the denaturation process, for the ligand-dsDNA complexes, except for covalently bound cis-Pt, took place at higher temperatures compared to the unbound helix. Furthermore,...
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Fabrication and properties of electrode material composed of ordered titania nanotubes and pEDOT:PSS
PublicationWe report on the two-stage preparation method of electrode material composed of titania nanotubes and poly(3,4-ethylenedioxythiopene):poly(2-styrenesulphonate) conductive polymer (pEDOT:PSS). Initially, titania nanotube arrays were produced by the anodization process of Ti substrate. Next, the polymer was potentiostatically deposited onto the thermally annealed nanotube arrays from the electrolyte containing monomer and counter...
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Bis-phosphonated carbon nanotubes: one pot synthesis and their application as efficient adsorbent of mercury
PublicationEffective, one-pot method of CNTs phosphonylation is presented. Cheap and readily available reagents are used, so the process can be easily transferred to large-scale production. The product was analyzed using spectroscopic methods (FTIR, UV-vis, XPS). Thermal properties of the bis-phosphonated nanotubes are reported for the first time. Newly obtained material was tested as an adsorbent for mercury removal from water. The sorption...
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Evidence for solid state electrochemical degradation within a small molecule OLED
PublicationAcridone derivative have been synthesised and used as OLED (Organic Light Emitting Diode) emitters which were found to be electroactive. Electrochemical investigations showed a side reaction takes place inside an active layer which diminished the overall device efficiency. By using a dopant and host active layer architecture, the formation of the by product was removed. The by-product was identified as a σ-dimer formed inside an...
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Heteroleptic cobalt(II)tri-tert-butoxysilanethiolates in search of new biomimetic complexes
PublicationW ramach prowadzonych badań mających na celu syntezę układów mimikujących centra aktywne wybranych metaloprotein zostały otrzymane dwa nowe heterlopetyczne tri-tert-butoksysilanotiolany kobaltu(II) w reakcji bimetalicznego kompleksu kobaltu(II) zawierającego już reszty silanotiolanowe z pochodnymi pirydyny: 3,5-dimetylopirydyny i dibenzyloaminy. Otrzymane związki zostały scharakteryzowane strukturalnie za pomocą analizy rentgenostrukturalnej,...
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Cobalt(II) tri-tert-butoxysilanethiolates with bidentate spacer ligands
PublicationOtrzymano szereg nowych tri-tert-butoksysilanotiolanów Co(II) z dwudonorowymi N,N'-ligandami takimi jak pirazyna, chinoksalina i 4,4'-bipy. W przypadku pirazyny i chinoksaliny otrzymane kompleksy są bimetaliczne, w których atomy metali połączone są odpowiednią aminą. Użyty do syntezy 4,4'-bipy pozwolił na otrzymanie dwóch odmian polimorficznych kompleksu {[Co{SSi(tBuO)3}2]2(μ-4,4'bipy)}, a także polimeru koordynacyjnego o wzorze...
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Photoconversion of carbon dioxide to methane and light hydrocarbons
PublicationFotokonwersja ditlenku węgla do lekkich węglowodorów jest czystym i przyjaznym dla środowiska procesem, pozwalającym na obniżenie emisji CO2 przy jednoczesnym generowaniu paliwa. Badanie efektywności procesu fotokonwersji CO2 prowadzono w obecności promieniowania UV-Vis, pary wodnej oraz fotokatalizatorów Ag-TiO2, Au-TiO2, Ag/Au-TiO2 otrzymanych w mikroemulsji woda/AOT/cykloheksan. Najwyższą aktywność w procesie fotoredukcji...
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APPLICATION OF MAGNETIC NANOPARTICLES FOR WATER TREATMENT
PublicationIn this study magnetic nanoparticles were fabricated and used for water treatment. Nanoparticles were prepared in two ways. The first one involved NiZn ferrite nanoparticles synthesized by co-precipitation of metal cations with sodium hydroxide at high temperature. The second one featured maghemite nanoparticles was prepared by saltassisted solid-state reaction. Modification and functionalization of nanoparticles surface was investigated....
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Photocatalytic activity of boron-modified TiO2 under visible light: The effect of boron content, calcination temperature and TiO2 matrix
PublicationPrzedstawiono wpływ temperatury kalcynacji (200, 300, 350, 400, 450 oraz 600oC) na fotoaktywność w świetle widzialnym (l> 400 nm) oraz właściwości powierzchniowe TiO2 modyfikowanego borem. B-TiO2 został przygotowany metodą impregnacji powierzchniowej. Jako prekursor bory wykorzystano ester trietylowy kwasu borowego (BATE). Charakterystyka otrzymywanych fotokatalizatorów obejmowała wyznaczenie powierzchni właściwej, właściwości...
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Studies of the effects of antifungal cationic derivatives of amphotericin B on human erythrocytes.
PublicationBadano nową grupę kationowych pochodnych amfoterycyny B pod kątem zależności pomiędzy ich zdolnością do asocjacji i selektywną toksycznością. We wszystkich przypadkach stosowano amfoterycynę B jako związek odniesienia. Jako miarę efektu toksycznego in vitro badanych związków stosowano wypływ wewnątrzkomórkowego potasu oraz hemolizę. Miarą aktywności przeciwgrzybowej był MIC i utrata potasu wewnatrzkomórkowego. Do oceny stopnia...
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Monosubstituted hydrazone β-cyclodextrin derivatives for pH-sensitive complex formation with aromatic drugs
PublicationA new and convenient synthetic pathway was developed to produce monosubstituted cyclodextrins with high yields. Each of the β-cyclodextrin derivatives described in this work has an aromatic substituent connected with cyclodextrin core by a pH-sensitive hydrazone linker and a carbon chain. Carbon chains differ in lengths having one or three carbon atoms. The correlation between water solubility and linker length was determined using...
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Ti-Fe2O3/In2O3 as photoactive material: The role of the substrate in photoelectrochemical water oxidation
PublicationThe layers of Ti-Fe2O3/In2O3 were prepared on the different substrates using hydrothermal method: Ti/TiO2 nanotubes, Ti foil, FTO and FTO/TiO2. Materials were characterized using scanning electron microscopy, XRD, Raman, UV-Vis, and X-ray photoelectron spectroscopy and tested as photoanodes for water oxidation under illumination. The formation of heterojunction on the TiO2 nanotubes increases photocurrent of water oxidation at...
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Determination of flavanols by liquid chromatography with fluorescence detection. Application to the characterization of cranberry-based pharmaceuticals through profiling and fingerprinting approaches
PublicationIn this work, a new method based on reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection (FLD) was established for the determination of catechins and related oligomeric proanthocyanidins (PACs) in cranberry-based pharmaceuticals. Compounds were recovered by liquid extraction using methanol/water/hydrochloric acid (60:39:1, v:v:v) as the extraction solvent. The chromatographic separation was carried...
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Preparation of platinum modified titanium dioxide nanoparticles with the use of laser ablation in water
PublicationWe report on the preparation method of nanocrystalline titanium dioxide modified with platinum by using nanosecond laser ablation in liquid (LAL). Titania in the form of anatase crystals has been prepared in a two-stage process. Initially, irradiation by laser beam of a titanium metal plate fixed in a glass container filled with deionized water was conducted. After that, the ablation process was continued, with the use of a platinum...
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Multi-functional monodispersed SiO2-TiO2 core-shell nanostructure and TEOS in the consolidation of archaeological lime mortars surfaces
PublicationArchaeological traditional lime mortars are susceptible to many environmental conditions such as the impact of water (rain, humidity, groundwater, etc.), variation of temperatures' degrees, wind and/or pollution. Accordingly, this research aims to provide newly assessed multifunctional Nano-coating for the purpose of archaeological lime mortar protection. For this, the study combined physicochemical and mechanical characterizations...
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Rapid development of the photoresponse and oxygen evolution of TiO2 nanotubes sputtered with Cr thin films realized via laser annealing
PublicationRecently, earth abundant transition metal oxides have gained particular attention as potential catalyst candidates due to their availability and low-cost comparing to substrates containing precious Pt or Au species. Herein, we present characterization of morphology, structure and electrochemical properties of pulsed 532 nm laser treated TiO2 nanotubes (NT) sputtered by the thin film of chromium. Scanning electron microscopy enables...
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The effect of nanoparticles size on photocatalytic and antimicrobial properties of Ag-Pt/TiO2 photocatalysts
PublicationAg-Pt-modified TiO2 nanocomposites were synthesized using the sol–gel method. Bimetallic modified TiO2 nanoparticles exhibited improved photocatalytic activity under visible-light irradiation, better than monometallic Ag/TiO2 and Pt/TiO2 nanoparticles (NPs). All modified powders showed localized surface plasmon resonance (LSPR) in visible region. The photocatalysts’ characteristics by X-ray diffractometry (XRD), scanning transmission...
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Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement
PublicationDoping and modification of TiO2 nanotubes were carried out using the hydrothermal method. The introduction of small amounts of cobalt (0.1 at %) into the structure of anatase caused an increase in the absorption of light in the visible spectrum, changes in the position of the flat band potential, a decrease in the threshold potential of water oxidation in the dark, and a significant increase in the anode photocurrent. The material...
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Chromogenic amides of pyridine-2,6-dicarboxylic acid as anion receptors
PublicationThe synthesis of simple, chromogenic pyridine-2,6-dicarboxylic acid amides, derivates of isomeric nitroanilines and aminonitrophenols, and their ion binding properties are described. The ligands' response to ionic species was examined by naked eye and was studied with the use of UV-Vis spectroscopy in DMSO and its mixture with water. The effect of the localisation and the type of the substituents in aromatic rings were discussed....
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Selective detection of F- by chromogenic tetrazole receptor
PublicationA chromogenic anion host 4, containing two amide functionalities linked to azo dye and tetrazole rings was synthesized and its complexes with various anions were investigated. The results show that receptor 4 can recognize selectively biologically important F- ion. The binding affinity for F- was investigated by naked-eye colour change, UV-Vis and 1H NMR spectroscopy. Addition F- ion in CH3CN and DMSO to receptor 4 cause a colour...
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Classification and fingerprinting of kiwi and pomelo fruits by multivariate analysis of chromatographic and spectroscopic data
PublicationThe fingerprinting capacity of two analytical techniques, HPLC and UV-Vis spectroscopy in the case of fruits samples (kiwi and pomelo) has been investigated. The multivariate exploratory techniques were used for sample discrimination according to the fruit species and subspecies. The combination of principal component analysis with linear discriminant analysis is opening new directions in the fingerprinting analysis. The classifications...