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Wyniki wyszukiwania dla: spektrofotometria uv-vis
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Pilot-Scale Studies of WO3/S-Doped g-C3N4 Heterojunction toward Photocatalytic NOx Removal
PublikacjaDue to the rising concentration of toxic nitrogen oxides (NOx) in the air, effective methods of NOx removal have been extensively studied recently. In the present study, the first developed WO3/S-doped g-C3N4 nanocomposite was synthesized using a facile method to remove NOx in air efficiently. The photocatalytic tests performed in a newly designed continuous-flow photoreactor with an LED array and online monitored NO2 and NO system...
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Enhancement of photocatalytic-based processes by mono- and bimetallic (CuPd) rutile loaded nanoparticles for antibiotic resistance genes and facultative pathogenic bacteria removal
PublikacjaThe aim of the study was the strong reduction of facultative pathogenic bacteria (FPB), and clinically relevant antibiotic resistance genes (ARGs) from secondary effluent. To evaluate the ARGs removal efficiency comparative study of individual unit processes and combined AOPs has been performed. The present work investigated: i) removal of selected ARGs, namely blaTEM, ermB, qnrS, tetM, five FPB as well as 16S rDNA and the integrase...
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Alternatywne metodyki wydzielania, identyfikacji oraz oznaczania siarki elementarnej w glebie z wykorzystaniem ekstrakcji do nisko polarnej cieczy, chromatografii cieczowej i spektrofotometrii
PublikacjaW niniejszej pracy - na podstawie przeglądu literatury oraz badań -opracowano nowe metodyki wydzielania, rozdzielania od składników towarzyszących, identyfikacji oraz oznaczania siarki elementarnej w glebach, szczególnie zanieczyszczonych nisko lotnymi produktami pochodzącymi z ropy naftowej. Zastosowano ekstrakcję siarki, nisko oraz średnio polarnych składników gleby do niepolarnego n-heksanu. Rozdzielano składniki ekstraktów...
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Monometallic nanoparticles decorated and rare earth ions doped KTaO3/K2Ta2O6 photocatalysts with enhanced pollutant decomposition and improved H2 generation
PublikacjaNew, monometallic nanoparticles (MNPs) decorated surface and rare earth (RE) ions doped lattice of perovskite-type (KTaO3)/pyrochlore-type (K2Ta2O6) photocatalysts were successfully prepared by facile hydrothermal incorporation of RE ions into KTaO3/K2Ta2O6 lattices followed by photodeposition of MNPs. The impact of noble metal type (MNPs = Au, Pt, Rh) and rare earth dopant type (RE = Er, Pr) on the physicochemical properties correlated...
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Mono- and bimetallic (Pt/Cu) titanium(IV) oxide photocatalysts. Physicochemical and photocatalytic data of magnetic nanocomposites’ shell
PublikacjaSurface 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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Synthesis and properties of azobenzocrown ethers with pi-electron donor, or pi-electron donor and pi-electron acceptor group(s) on benzene rings
PublikacjaZsyntezowano nowe etery azobenzokoronowe o różnej wielkości makropierścienia i z różnymi podstawnikami w resztach benzenowych. Korony te posiadają w pierścieniach benzenowych, w pozycji para do grupy azo grupy funkcyjne o charakterze π-elektronodonorowym lub π-elektronoakceptorowym. Zbadano zdolność kompleksowania jonów metali przez te korony, w roztworze, metodą spektrofotometrii UV-vis. Ustalono strukturę 19-członowego eteru...
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Oczyszczone ścieki źródłem kwasów humusowych w wodach powierzchniowych
PublikacjaZbadano scieki po II stopniu oczyszczania, pochodzące z oczyszczalni scieków Jamnok. Koszalina oraz Unieście. Stwierdzono,że zanalizowane, oczyszczone ścieki charakteryzują się zblizonym stężeniem kwasów humusowych i składem pierwiastkowym oraz podobnymi widmami absorpcyjnymi UV (A2/3 ok. 1.7). Widma absorpcyjne VIS wskazuja na większy stopień skondensowania cząstek kwasów humusowych z Unieścia a kwasy humusowe wyizolowane ze scieków...
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Preparation and characterisation of visible light responsive iodine doped TiO2 electrodes
PublikacjaPraca przedstawia charakterystykę domieszkowanego jodem ditlenku tytanu (I-TiO2) otrzymanego na drodze hydrotermicznej syntezy, gdzie prekursor stanowiły komplesy tytanu (IV) z ligandami zawierającymi atom jodu. Struktura nowego materiału została opisana za pomocą technik XPS, XRD, UV-vis i FT-IR-ATR. Badania te potwierdziły, że otrzymany proszek I-TiO2 ma zmniejszoną przerwę energetyczną. Praca prezentuje również badania elektrochemiczne...
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Functionalized azobenzocrown ethers as sensor materials—The synthesis and ion binding properties
PublikacjaNew 13- and 16-membered azobenzocrown ethers with aromatic amino, amide, ether–ester or ether–amide residue in para position to an azo moiety were obtained. Acid–base properties and ion binding ability of the colored compounds were studied by spectroscopic methods: UV–vis, fluorimetry and 1H NMR spectroscopy. Selected azobenzocrowns were tested as ionophores in ion-selective membrane electrodes (ISEs) – classic and miniature all...
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Synthesis and properties of new 'N,'N-phenyltetrazole podand
PublikacjaThe synthesis of a new chromogenic N,N-phenyltetrazole receptor is reported here. The cationbinding properties of this receptor in solution were investigated by naked-eye colour change, electrochemical methods and UV-Vis spectroscopy in various solvents (CH3CN, dimethylsulphoxide (DMSO), DMSO/H2O, CH3CN/H2O and CH3CN/MeOH). In addition, the receptor was used as a sensing material in ion-selective membrane electrodes. The selectivity...
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Facile preparation of extremely photoactive boron-doped TiO2 nanotubes arrays
PublikacjaDoping of TiO2 nanotube arrays with boron was realized via electrochemical treatment of as-anodized titania immersed in electrolyte containing boric acid. The photoactivity of doped and pure titania was examined by means of photoelectrochemical and photocatalytic response under UV-vis irradiation. The results showed that photocurrent density of B-TNTs is remarkably higher (7.5 times) than density of pure TiO2 nanotube arrays. Furthermore,...
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Synthesis, spectroscopy and crystal structure determination of heteroleptic cobalt(II) silanethiolates with pyridine derivatives
PublikacjaCztery nowe tri-tert-butoksysilanotiolanowe kompleksy kobaltu(II) z 3- i 4-metylopirydyną zostały zsyntetyzowane i scharakteryzowane. Monometaliczne kompleksy otrzymano w reakcji bimetalicznego kompleksu [Co(SSi(OtBu)3(NH3)]2, który posłużył jako substrat kobaltu(II). Nowe związki zostały scharakteryzowane przy użyciu rentgenografii strukturalnej oraz spektroskopii UV-vis i FT-IR, a także za pomocą analizy elementarnej. Kompleksy...
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Scalable Route toward Superior Photoresponse of UV-Laser-Treated TiO2 Nanotubes
PublikacjaTitanium dioxide nanotubes gain considerable attention as a photoactive material due to chemical stability, photocorrosion resistance, or lowcost manufacturing method. This work presents scalable pulsed laser modification of TiO2 nanotubes resulting in enhanced photoactivity in a system equipped with a motorized table, which allows for modifications of both precisely selected and any-large sample area. Images obtained from scanning...
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Improvement of opipramol base solubility by complexation with β-cyclodextrin
PublikacjaOpipramol (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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Chromogenic azole diazothiacrown ethers
PublikacjaZsyntezowane zostały etery koronowe zawierające atomy siarki, dwa ugrupowania azowe oraz fragment pirolu lub imidazolu w makropierścieniu.Zbadana została zdolność zsyntezowanych związków makrocyklicznych pod kątem kompleksowania jonów metali metodą spektrofotometrii UV-vis.Największe zmiany spektralne zaobserwowano pod wpływem jonów ołowiu, miedzi, cynku, niklu, kobaltu oraz srebra.W przypadku jonów metali I i II grupy układu okresowego...
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Lower rim substituted tert-butylcalix[4]arenes (II). Complexing ability of5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis-O-(piperidinylcarbonyl)me- thylenecalix[4]arene. The crystal structures of the ligand and its sodium complex
PublikacjaSyntezowano kompleksy wymienionego w tytule liganda z chlorkiem sodu i azotanami itru(III), lantanu(III), samaru(III) i gadolinu(III) w reakcji liganda i odpowiedniej soli, które charakteryzowano za pomocą widm IR, UV-vis,1H NMR, FAB-MS, a także za pomocą analizy elementarnej. W reakcji wymiany z kompleksu z sodem otrzymywano kompleksy z lantanowcami. Określono strukturę krystaliczną wolnego liganda i jego kompleksu z sodem za...
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Widma elektronowe kompleksów miedzi(II) z imidazolem w ciele stałym i w roztworze
PublikacjaZsyntetyzowano szereg związków kompleksowych miedzi(II) z ligandami chlorkowymi i różnymi alkilowymi pochodnymi imidazolu: 4(5) metyloimidazolem, 2-etyloimidazolem, 2-izopropyloimidazolem i 2-etylo-4-metyloimidazolem. Otrzymane głównie kompleksy jednordzeniowe oraz jeden kompleks dwurdzeniowy (z 2-etyloimidazolem). Zbadano widma elektronowe otrzymanych kompleksów w roztworach metanolowych i porównano je z widmami otrzymanymi z...
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Chemical composition analysis and authentication of whisky
PublikacjaW pracy przedstawiono informacje dotyczące porównania różnych rodzajów whisky i innych napojów alkoholowych, identyfikacji różnych rodzajów whisky, oceny jakości i potwierdzania autentyczności whisky. Ponadto w pracy omówiono różne techniki stosowane w analizie whisky, takie jak gazową i cieczową chromatografię z różnymi detektorami (FID, AED, UV-vis), nos elektroniczny, spektrometrię absorpcji atomowej i spektrometrię mas. Ponadto...
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A study on the interaction of rhodamine B with methylthioadenosine phosphorylase protein sourced from an Antarctic soil metagenomic library.
PublikacjaThe presented study examines the phenomenon of the fluorescence under UV light excitation (312 nm) of E. coli cells expressing a novel metagenomic-derived putative methylthioadenosine phosphorylase gene, called rsfp, grown on LB agar supplemented with a fluorescent dye rhodamine B. For this purpose, an rsfp gene was cloned and expressed in an LMG194 E. coli strain using an arabinose promoter. The resulting RSFP protein was purified...
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Facet effect of TiO2 nanostructures from TiOF2 and their photocatalytic activity
PublikacjaIn this study, special attention is focused on the design of TiO2 morphology and microstructure in the two-step preparation procedure using TiOF2 as a precursor to study their photodegradation mineralization efficiency. Firstly, TiOF2 was synthesized by a simple solvothermal method using titanium(IV) tetrafluoride, which was further used as a precursor in preparation of anatase 2D nanosheets, octahedral, decahedral, and rectangular prisms...
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Heat treatment effect on Eu3+ doped TeO2-BaO-Bi2O3 glass systems with Ag nanoparticles.
PublikacjaGlass systems of 73TeO2-4BaO-3Bi2O3-2Eu2O3-xAg ( in molar ratio where x= 0, 1, 2, 3) compositions have been successfully synthesized. Silver nanoparticles were obtained with the employment of heat treatment (HT) procedure executed at 350 °C. Glass transition temperatures of different compositions have been determined through DSC measurements. XRD measurement results presented characteristic amorphous halo indicating lack of long...
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Scheelite-Type Wide-Bandgap ABO4 Compounds (A = Ca, Sr, and Ba; B = Mo and W) as Potential Photocatalysts for Water Treatment
PublikacjaIn the present study, alkaline-earth metal scheelite-type compounds ABO4 (A = Ca, Sr, Ba, B = Mo, W) synthesized by a hydrothermal method were systematically studied. The as-obtained photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area analysis (BET), UV–Vis diffuse reflectance spectroscopy (DR/UV-Vis), photoluminescence, and thermoluminescence (TL)...
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Photoactivity of decahedral TiO2 loaded with bimetallic nanoparticles: Degradation pathway of phenol-1- 13 C and hydroxyl radical formation
PublikacjaDecahedral TiO2decorated with bimetallic nanoparticles were synthesized via radiolysis and photode-position method. The effect of bimetallic surface composition (Ag Pt, Ag Au, Au Pd, Au Pt) as well asdeposition technique (simultaneous or sequential) on the photocatalytic activity in phenol degradationand efficiency of hydroxyl radicals generation under UV–vis light irradiation were investigated. Modifiedand pristine decahedral...
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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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Similarities and differences in d6 low-spin ruthenium, rhodium and iridium half-sandwich complexes: synthesis, structure, cytotoxicity and interaction with biological targets
PublikacjaIn this paper, we discussed the similarities and diferences in d6 low-spin half-sandwich ruthenium, rhodium and iridium complexes containing 2,2′-biimidazole (H2biim). Three new complexes, {[RuCl(H2biim)(η6 -p-cymene)]PF6}2·H2O (1), [(η5 - Cp)RhCl(H2biim)]PF6 (2), and [(η5 -Cp)IrCl(H2biim)]PF6 (3), were fully characterized by CHN, X-ray difraction analysis, UV–Vis, FTIR, and 1 H, 13C and 15N NMR spectroscopies. The complexes exhibit...
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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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KTaO3-based nanocomposites for air treatment
PublikacjaA series of single semiconductors and their nanocomposites combination (such as KTaO3 + CdSe + SrTiO3; KTaO3 + CdS +WO3; KTaO3 + CdS + MoS2) were prepared using hydrothermal route. Photocatalytic activity of as-prepared nanocomposites was estimated by photocatalytic degradation of toluene in the gas phase using light-emitting diodes (LEDs, 375 nm) in four subsequent cycles. The nanocomposites were characterized by scanning electron...
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Synthesis and Characterization of Monometallic (Ag, Cu) and Bimetallic Ag-Cu Particles for Antibacterial and Antifungal Applications
PublikacjaIn this paper, the experimental studies are concerned with the effect of the synthesis parameters on the formation of monometallic Ag and Cu nanoparticles (NPs). We consider the synthesis strategies verification for the bimetallic core-shell and alloy particles preparation. It was successfully obtained by chemical reduction method. The obtained colloidal solution is characterized by the transmission electron microscopy (TEM) with...
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The Influence of Titania Electrode Modification with Lanthanide Ions Containing Thin Layer on the Performance of Dye-Sensitized Solar Cells
PublikacjaThe lanthanide and scandium groups ions (except Pm and Ac) have been used as dopants of TiO2 film in dye-sensitized solar cells. The X-ray diffraction spectra show that the modification has no influence on the structure of the electrode; however, the diffuse reflectance UV-Vis measurements exhibit significant changes in the electronic properties of modified electrodes. The appearance of energy barrier preventing photoexcited electron...
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Electrochemically Induced Synthesis of Triphenylamine-based Polyhydrazones
PublikacjaTriphenylamine-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
PublikacjaNatural 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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Lanthanide co-doped TiO2: the effect of metal type and amount on surface properties and photocatalytic activity
PublikacjaPreparation of new rare earth metal-containing TiO2 nanocomposites (Nd3+/Er3+, Nd3+/Eu3+, Eu3+/Ho3+-TiO2) using sol–gel route and their photoactivity under visible and ultraviolet light is reported. The obtained photocatalysts were subsequently characterized by Brunauer–Emmett–Teller (BET) method, UV–Vis diffuse-reflectance spectroscopy (DRS), luminescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction...
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Kontrola procesu wytwarzania biowodoru z gliceryny podczas fermentacji beztlenowej
PublikacjaProdukcja 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
PublikacjaAktywne 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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Cation sensing by diphenyl-azobenzocrowns
PublikacjaMetal 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
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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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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In situ spectroelectrochemical and theoretical study on the oxidation of a 4H-imidazole-ruthenium dye adsorbed on nanocrystalline TiO2thin film electrodes
PublikacjaTerpyridine 4H-imidazole-ruthenium(ii) complexes are considered promising candidates for use as sensitizers in dye sensitized solar cells (DSSCs) by displaying broad absorption in the visible range, where the dominant absorption features are due to metal-to-ligand charge transfer (MLCT) transitions. The ruthenium(iii) intermediates resulting from photoinduced MLCT transitions are essential intermediates in the photoredox-cycle...
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Efficient Method for the Concentration Determination of Fmoc Groups Incorporated in the Core-Shell Materials by Fmoc–Glycine
PublikacjaIn 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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Preparation and characterization of Pt–N/TiO2 photocatalysts and their efficiency in degradation of recalcitrant chemicals
PublikacjaSeries 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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Complexes of manganese(II) tri-tert-butoxysilanethiolate with chelating N-donor ligands.
PublikacjaTri-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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Photodegradation of lauric acid at an anatase single crystal surface studied by atomic force microscopy
PublikacjaBadania 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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Role of nitrogen in optical and electrical band gaps of hydrogenated/hydrogen free carbon nitride film
PublikacjaWe 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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Fluorescence of p-hydroxyazobenzocrowns – Tautomeric equilibrium effect
PublikacjaThe 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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Authentication of whisky due to its botanical origin and way of production by instrumental analysis and multivariate classification methods
PublikacjaHeadspacemass-spectrometry (HS-MS), mid infrared (MIR) and UV–vis spectroscopywere used to authenticate whisky samples from different origins and ways of production ((Irish, Spanish, Bourbon, TennesseeWhisky and Scotch). The collected spectra were processed with partial least-squares discriminant analysis (PLS-DA) to build the classification models. In all cases the five groups ofwhiskieswere distinguished, but the best resultswere...
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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
PublikacjaA 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
PublikacjaA 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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Tailoring Physicochemical Properties of V2O5 Nanostructures: Influence of Solvent Type in Sol-Gel Synthesis
PublikacjaThe influence of different solvents, including aqueous and nonaqueous types, on the physicochemical properties of V2O5 nanostructures was thoroughly investigated. Various characterization techniques, such as XRD, XPS, FTIR, Raman spectroscopy, UV-vis DRS, SEM, TEM, and BET, were employed to analyze the obtained materials. Additionally, the adsorption properties of the synthesized V2O5 nanostructures for methylene blue were examined,...
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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
PublikacjaNanocrystalline 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...