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Search results for: EMERGING ORGANIC POLLUTANTS
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A configurational and conformational study of (−)-Oseltamivir using a multi-chiroptical approach
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Stereochemical Assingment of β -lactam Antibiotics and their Analogues by Electronic Circular Dichroism Spectroscopy
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Base-Catalyzed, Solvent-Free Synthesis of Rigid V-Shaped Epoxydibenzo[b,f][1,5]diazocines
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In Depth Analysis of Chiroptical Properties of Enones Derived from Abietic Acid
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Photoinduced Isomerization of 23-Oxosapogenins: Conformational Analysis and Spectroscopic Characterization of 22-Isosapogenins
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Chromane helicity rule – scope and challenges based on an ECD study of various trolox derivatives
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Amine-Catalyzed Direct Aldol Reactions of Hydroxy- and Dihydroxyacetone: Biomimetic Synthesis of Carbohydrates
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Bypassing the stereoselectivity issue: transformations of Kinugasa adducts from chiral alkynes and non-chiral acyclic nitrones
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A Unique and Stable Polyproline I Helix Sorted out from Conformational Equilibrium by Solvent Polarity
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Practical Method for the Absolute Configuration Assignment of tert/tert 1,2-Diols Using Their Complexes with Mo2(OAc)4
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The Oxolane Ring Opening of Some Muramic Acid Derivatives Under Acidic Conditions
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Chemical Reduction of 2,4,6-Tricyano-1,3,5-triazine and 1,3,5-Tricyanobenzene. Formation of Novel 4,4‘,6,6‘-Tetracyano-2,2‘-bitriazine and Its Radical Anion
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Toward an Understanding of the Chemiluminescence Accompanying the Reaction of 9-Carboxy-10-methylacridinium Phenyl Ester with Hydrogen Peroxide
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Multispectral impedance quality testing of coil-coating system using principal component analysis
PublicationThe task of quality checking of the coil-coated system was undertaken using impedance spectroscopy. In order to properly characterize the system the new impedance spectrum was calculated as an averaged result of 12 experimental spectra obtained from 12 different places of the sample at the same time of immersion in 3% of NaCl. The experimental spectra were recorded for a 24-h period at 1 h intervals between starting points of each...
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Investigation of morphological and electrical properties of the PMMA coating upon exposure to UV irradiation based on AFM studies
PublicationCelem badania było określenie wpływu promieniowania ultrafioletowego na morfologię powierzchni powłoki i na jej właściwości elektryczne. Cienka powłoka z polimetakrylanu metylu została nałożona na podłoże stalowe metodą zanurzeniową. Oceny stanu przed ekspozycją UV i w jej trakcie dokonywano przy użyciu mikroskopu sił atomowych. Na obrazach AFM zaobserwowano pojawienie się mikropęknięć. Celem zweryfikowania czy wykryte nieciągłości...
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Fate of Ionic Liquids in Soils and Sediments
PublicationZrozumienie losu cieczy jonowych w glebach i osadach dennych jest istotnym elementem ich implementacji z zachowaniem idei zrównoważonego rozwoju. Niniejsza publikacja zawiera analizę i podsumowanie danych dotyczących oddziaływań cieczy jonowych w roztworach wodnych oraz agregacji na powierzchniach stałych. Zaobserwowano, że silnie lipofilowe ciecze jonowe zawierające długi łańcuch węglowodorowy lub duży organiczny anion wykazują...
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Enantiomeric Resolution of N,N'-Dimethyldithiodianthranilide through Diastereomeric silver(I) complex. Chiroptical spectra, racemization barrier and molecular self-assembly
PublicationN,N'-dimetyloditiodiantranilid, związek o chiralności płaszczyznowej, rozdzielono na enancjomery. Optycznie czynne molekuły uzyskano w wyniku tworzenia chiralnego kompleksu N,N'-dimetyloditiodiantranilidu z solą srebrową kwasu (1S)-kamforosulfonowego. W oparciu o badania rentgenostrukturalne monokryształu uzyskanego kompleksu określono absolutną konfigurację przykoordynowanego ligandu jako (R). Enancjomery N,N'-dimetyloditiodiantranilid...
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Conformation Properties, Chiroptical Spectra, and Molecular Self-Assembly of 2,3-Piperazinodiones and Their Dithiono Analogues
PublicationRodzina chiralnych cyklicznych oksamidów została otrzymana przez kondensację optycznie czynnych 1,2-diamin ze szczawianem dietylu. Tionowanie produktów odczynnikiem Lawessona doprowadziło do chiralnych 2,3-dipiperazynodionów. Geometrie cząsteczkowe badano z użyciem obliczeń kwantowo-mechanicznych DFT i porównano z wynikami analizy krystalograficznej. Sześcioczłonowy pierścień heterocykliczny przyjmuje konformację półkrzesłową,...
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Synthesis and structural investigation of N-acyl selenophosphoramides
PublicationN-acylowane amidy kwasu O,O-neopentylidenomonoselenofosforowego, w zależności od podstawnika na atomie azotu, krystalizują jako konformery zawierające selen w pozycji ekwatorialnej bądź aksjalnej. Wyniki tych eksperymentów wyjaśniono działaniem efektu anomerycznego.
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Lower rim substituted p-tert-Butylcalix[4]arenes: Part XI. New ester derivatives of calix[4]arene, their ionophoric properties and x-ray structure studies
PublicationPrzedstawiono syntezę 6-ciu nowych estrowych pochodnych kaliks[4]arenuw konformacji stożkowej. Pierwsze badania kompleksowania jonów metali przeprowadzone w membranach elektrod jonoselektywnych (ISE) potwierdziły kompleksowanie jonów sodu w sposób selektywny. Zaprezentowano strukturę rentgenowską monokryształów związku 6.
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Solid phase microextraction combined with chromatography - a powerful tool for determination of warfare agents and related compounds
PublicationOpisano zastosowanie mikroekstrakcji do fazy stacjonarnej do izolacji wzbogacania środków bojowych i produktów ich degradacji w powietrzu, wodzie i glebie oraz próbkach bilogicznych. Na etapie oznaczeń końcowych stosuje się najczęściej chromatografię gazową. Anality można pobierać przez bezpośrednie zanurzenie włókna w próbce ciekłej i gazowej oraz w fazie nadpowierzchniowej. Stosując SPME-GC można osiągnąć niskie granice oznaczalności...
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Application of Monoferrocenylsumanenes Derived from Sonogashira Cross-Coupling or Click Chemistry Reactions in Highly Sensitive and Selective Cesium Cation Electrochemical Sensors
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Correction to Aromatic Dendrimers Bearing 2,4,6-Triphenyl-1,3,5-triazine Cores and Their Photocatalytic Performance
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Supramolecular Interactions between β-Cyclodextrin and the Nucleobase Derivatives of Ferrocene
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Aromatic Dendrimers Bearing 2,4,6-Triphenyl-1,3,5-triazine Cores and Their Photocatalytic Performance
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Influence of Carbohydrate Residues on Antibacterial Activity of Vancomycin
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Benzophosphol-3-yl Triflates as Precursors of 1,3-Diarylbenzophosphole Oxides
PublicationAsimplemethodforthesynthesisof3-arylbenzophospholeoxidesunderSuzuki−Miyauracouplingconditionshasbeenpresented.Itemploysbenzophosphol-3-yltriflatestartingmaterialswhich,priortoourwork,hadnotbeenusedforthesynthesisof3-arylbenzophospholeoxides.Thereactionsproceedover24handprovidealibraryof3-arylbenzophospholeoxides.Thesyntheticaccesstothebenzophosphol-3-yltriflateshasbeenimproved.Thepreliminaryphotophysicalpropertiesofsome3-arylbenzophospholeoxideshavebeeninvestigatedbyabsorptionandemissionmeasurements.Thetheoreticalcalculationswereperformedtoestablishstructure−propertyrelationships.
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Pincer Complexes Based on Phosphinoaminopyridines: Synthesis, Structural Characterization and Catalytic Applications
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Thermal decomposition of polyurethane pressure-sensitive adhesives dispersions
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The thermal degradation of acrylic pressure-sensitive adhesives based on butyl acrylate and acrylic acid
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Arylation of enelactams using TIPSOTf: reaction scope and mechanistic insight
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Regioselective synthesis of novel 4,5-diaryl functionalized 3,4-dihydropyrimidine-2(1H)-thiones via a non-Biginelli-type approach and evaluation of their in vitro anticancer activity
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Anticorrosive and antimicrobial efficiency of photopolymerizable phosphorus (meth)acrylate oligomers-based coating materials
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Synthesis of Polycyclic δ-Lactams with Bridged Benzomorphan Skeleton: Selectivity and Diversity Driven by Substituents
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Small isomeric push–pull chromophores based on thienothiophenes with tunable optical (non)linearities
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Performance of zinc-rich coatings evaluated using AFM-based electrical properties imaging
PublicationThe paper presents the results of investigation of polyvinyl zinc-rich coating exposed to 97% relativehumidity atmosphere for 40 days. Condition of the coating and evolution of its protective properties weredetermined with the novel AFM-based approach capable of providing surface profiles, local dc currentmaps as well as local impedance spectra. The proposed technique allowed insight into the local changesof coating topography...
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Bio-based semi-aromatic polyesters for coating applications
PublicationLinear and branched bio-based semi-aromatic (co)polyesters were evaluated as resins for solvent-basedand powder coatings. Dimethyl-2,5-furandicarboxylate (DMF), 2,3-butanediol and various multifunc-tional comonomers were used to synthesize amorphous hydroxyl-end-capped (co)polyesters. The resinswere cross-linked using the -caprolactam blocked trimer of isophorone diisocyanate. Both the solvent-based and powder coatings proved to...
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Multivariate analysis of impedance data obtained for coating systems of varying thickness applied on steel
PublicationElectrochemical impedance spectroscopy (EIS) has proven to be a valuable test method for the electrochemical characterization of protective coatings on metals. The common way of analysis in impedance spectroscopy is to model the impedance spectrum by means of an equivalent circuit and to extract the quantity of interest using optimization techniques. A model, corresponding to the behavior of the sample under testing, is important...
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Transparent nanocomposite coatings based on epoxy and layered double hydroxide: Nonisothermal cure kinetics and viscoelastic behavior assessments
PublicationLayered double hydroxide (LDH) has a particular place in clay family because of its flame retardant action. The nanoplatelet-like structure of LDH makes possible development of polymer composites with cationic or anionic nature structures in which macromolecules are positioned in between nanoplatelet galleries. In this work, neat epoxy and its transparent nanocomposite coatings with sodium dodecylbenzene sulfonate (SDBS)-modified...
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The changes of crosslink density of polyurethanes synthesised with using recycled component. Chemical structure and mechanical properties investigations.
PublicationThis paper aims at the utilisation of glycerolysate (Gly) obtained in polyurethane recycling process by means of crude glycerine, which has in its structure hydroxyl end groups that allow for further processing. Polyurethanes (PUs) were synthesised using prepolymer method with the mixture of neat polyol and glycerolysate, in different ratios, with 4,4-diphenylmethane diisocyanate (MDI). The prepolymer was subsequently extended...
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Degradation of protective coatings in steel chimneys of flue gas desulfurisation system
PublicationThis paper presents problems associated with corrosion of steel stacks and changes in philosophy of corrosion protection when implemented into flue gas desulphurization systems. In-situ tests were taken by means of electrochemical impedance spectroscopy at the stack which discharges flue gas before wet lime/limestone desulphurization. A very quick electrolyte absorption by the spherical infill vinylester coating was found using...
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Determination of time dependence of coated metal electrical and electrochemical parameters during exposure using principal component analysis
PublicationThe use of the principal component analysis (PCA) permits the complex and quantitative analysis of the time dependence of electrical and electrochemical parameters of coated metal obtained by fitting impedance data. So far, changes in electrical and electrochemical parameters during exposure were analyzed independently. In this way, some of the information contained in the relationship between changes in parameters over time are...
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Unconditionally blue: Curing epoxy with polyethylene glycol (PEG) surface-functionalized Zn Fe3-O4 magnetic nanoparticles
PublicationNanoparticles govern early (chemical-controlled) and late (diffusion-controlled) stages of epoxy crosslinking, respectively. Surface functionalization of nanoparticles with macromolecules was recognized as an effective route to compensate for inadequate diffusion-controlled crosslinking. However, the effect of bulk composition amended with cations having catalytic effect towards epoxy ring opening has remained hitherto undescribed....
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An attempt to mechanistically explain the viscoelastic behavior of transparent epoxy/starch-modified ZnO nanocomposite coatings
PublicationThe effects of bare and starch-modified ZnO (ZnO-St) nanoparticles on viscoelastic and mechanical properties are studied by dynamic mechanical and tensile analyses. Transparent epoxy-based nanocomposite films are prepared by incorporating bare or starch-modified ZnO particles into the epoxy matrix. The results demonstrated that ZnO particles hindered the curing reactions and hence the final properties of the cured epoxy. As a result,...
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Flame retardant epoxy/halloysite nanotubes nanocomposite coatings: Exploring low-concentration threshold for flammability compared to expandable graphite as superior fire retardant
PublicationEpoxy nanocomposites containing halloysite nanotubes (HNTs) were developed and their low-concentration thresholds for thermal stability and flame retardancy were compared with that of epoxy system containing expandable graphite (EG), as a reference with superior flame retardancy. The effects of HNTs and EG on the peak of Heat Release Rate (pHRR), Total Heat Release (THR), and Time-To-Ignition (TTI) of the prepared samples were...
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Curing behavior of epoxy/Fe 3 O 4 nanocomposites: A comparison between the effects of bare Fe 3 O 4 , Fe 3 O 4 /SiO 2 /chitosan and Fe 3 O 4 /SiO 2 /chitosan/imide/phenylalanine-modified nanofillers
PublicationIn this study, Fe3O4 magnetic nanoparticles (MNPs) were synthesized (B-MNP) and then modified with SiO2 to form Fe3O4/SiO2 core/shell MNPs. The Fe3O4/SiO2 MNPs were chemically functionalized with chitosan so as to gain Fe3O4/SiO2/Chitosan (CH-MNP). The CH-MNP was functionalized with a macromolecule containing imide and phenylalanine precursors to gain Fe3O4/SiO2/Chitosan/imide/phenylalanine based MNPs (CH-IM-MNP). The differences...
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Acid-aided epoxy-amine curing reaction as reflected in epoxy/Fe3O4 nanocomposites: Chemistry, mechanism, and fracture behavior
PublicationThis work seeks to answer the question whether or not the presence of acid functional groups accelerate epoxyamine curing reaction. Epoxy/Fe3O4 nanocomposite was considered as a case, where discussions are based on chemistry, mechanism behind curing reactions and fracture behavior influenced by acid assistance to crosslinking. Fe3O4 magnetic nanoparticles (MNPs) with nanosilica decorative layer (B-MNP) were synthesized and subsequently...
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Towards β-selectivity in functional estrogen receptor antagonists
PublicationBased on the benzo[b]naphtho[1,2-d]furan and benzo[b]naphtho[1,2-d]thiophene frameworks, a series of ligands with different basic side chains (BSCs) has been synthesized and pharmacologically evaluated. Also, their binding modes have been modelled using docking techniques. It was found that the introduction of a BSC in these systems brings about a decrease of affinity for both estrogen receptors α and β in an in vitro competitive...
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Helicity discrimination in N,N'-dibenzoyl-1,2,3,4,7,8,9,10-octahydro-1,10-phenanthrolines and their thiono- and selenocarbonyl analogues by inclusion complexation with chiral diols
PublicationX-ray crystallographic analysis of the title compounds revealed that they assume a folded helical con- formation of an approximate C2 symmetry in the solid state. Dithioamide, diselenoamide and monoselenoamide were resolved to enantiomers by inclusion crystallization with optically active diols (TADDOLs). The absolute configuration of the guest molecules in the complexes was assigned as P. The optical activity of the resolved compounds...
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Stereoselective Alkylation of Indole with 5-Arylidene-Meldrum’s Acids in the Presence of Organocatalysts
PublicationBackground: Indole motif is frequently present in biologically active compounds. Enantiomerically pure or enriched 2,2-dimethyl-5-(aryl(1H-indol-3-yl)methyl)-1,3-dioxane-4,6-diones can be considered as a convenient starting point for the synthesis of a indole ring fused with cyclic ketones with biological activity. Preparation of chiral 2,2-dimethyl-5-(aryl(1H-indol-3-yl)methyl)-1,3-dioxane- 4,6-diones requires the reaction of...