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Search results for: SPEKTROSKOPIA 13C NMR
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Exploring the Reactivity of Unsymmetrical Diphosphanes toward Heterocumulenes: Access to Phosphanyl and Phosphoryl Derivatives of Amides, Imines, and Iminoamides
PublicationWe present a comprehensive study on the diphosphanation of iso(thio)cyanates by unsymmetrical diphosphanes. The reactions involving unsymmetrical diphosphanes and phenyl isocyanate or phenyl thioisocyanate gave rise to phosphanyl, phosphoryl, and thiophosphoryl derivatives of amides, imines, and iminoamides. The structures of the diphosphanation products were confirmed through NMR spectroscopy, IR spectroscopy, and single-crystal...
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Quality of limes juices based on the aroma and antioxidant properties
PublicationKaffir (Citrus hystrix) and Key (Citrus aurantifolia) limes juices were investigated and compared. Two dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOF-MS) was applied to assess the botanical origin of Kaffir and Key limes juices, based on volatile substances. The biggest differences in the contents of selected terpenes in Kaffir and Key limes occur in chemical compounds such as Limonene,...
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Complexation of amino acids derivatives in water by calix[4]arene phosphonic acids
PublicationSeries of the calix[4]arene phosphonic acids with various substituents at the lower rim was synthesized. Complexing properties of these receptors towards methyl esters of six amino acids strongly depended on the calix[4]arene conformation flexibility. The complex formation processes were monitored using 1H NMR spectroscopy (deuterated phosphate buffer at pD 7.3, 22 oC) and association constant values were evaluated. Inherently...
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Enzymatyczne przeestryfikowanie łoju wołowego i oleju rzepakowego bez i w obecności różnych rozpuszczalników
PublicationPorównywano produkty otrzymane na drodze enzymatycznego przestryfikowania. Stosowano olej rzepakowy i łój wołowy (4:6 w/w). Katalizatorem procesu był Lipozyme RM IM. Proces prowadzono bez i w obecności różnych rozpuszczalników (izooktan, heksan, toluen). Temp. wynosiła 55-65oC. Produkty przeestryfikowania rozdzielano metodą chromatografii kolumnowej na frakcje: TAG, WKT i DAG+MAG. Określano temp. topnienia i zawartość fazy stałej...
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Właściwości fizyczne frakcji łoju oraz ich mieszanek
PublicationBadano frakcje łoju oraz mieszanki tłuszczowe zawierające te frakcje. W badanych tłuszczach oznaczano zawartość fazy stałej metodą pNMR. Stosowano różne metody termostatowania tłuszczów przed analizą. Wyznaczono również charakterystyki topnienia wybranych tłuszczów, stosując podobne procedury termostatowania jak w przypadku metody NMR. Wydłużenie czasu chłodzenia w temp. 0 st.C wpływało na wzrost zawartości fazy stałej. Im niższa...
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Chromogenic azomacrocycles with imidazole residue: Structure vs. properties
PublicationNew diazo macrocycles linked by hydrocarbon chain bearing imidazole or 4-methylimidazole residue have been synthetized with satisfactory yield (24–55%). The structure of macrocycles was confirmed by X-ray analysis and spectroscopic methods (1H NMR, MS, FTIR). Metal cation complexation studies were carried out in acetonitrile and acetonitrile-water system. It was found that azomacrocyles form triple-decker complexes with lead(II)....
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The structure of novel polyurethanes containing synthetic poly[(R,S)-3-hydroxybutyrate]
PublicationThe aim of this study was to estimate the structure of new polyurethanes with the potential to be used in medicine. Atactic poly[(R,S)-3-hydroxybutyrate], obtained via a ring-opening polymerization, and polycaprolactonediol or polyoxytetramethylenediol were used to built the soft segments. 4,4'-methylene dicyclohexyl diisocyanate and 1,4-butanediol were the components to form hard segments. Polyurethanes with low-molecular weight...
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Unassisted formation of hemiaminal ether from 4-aminopyridine and o-vanillin - experimental and theoretical study
PublicationThe reactions between o-vanillin and three isomeric aminopyridines lead to imines of diverse spatial conformation and reactivity. The direct products of these simple reactions carried out in methanol are either imine compounds formed in the reactions of 2- amino- and 3-aminopyridine with o-vanillin or the α-aminoether formed in the reaction of o-vanillin with 4-aminopyridine. The Schiff-type derivative of 4-aminopyridine and o-vanillin,...
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Atomic force microscopy based approach to local impedance measurements of grain interiors and grain boundaries of sensitized AISI 304 stanless steel
PublicationPraca prezentuje wyniki badań uzyskane z pomiarów techniką lokalnej spektroskopii impedancyjnej (LIS) wykonanych w trybie kontaktowym mikroskopii sił atomowych (AFM), które zostały przeprowadzone w lokalnych obszarach powierzchni ziarna austenitu i na granicy ziarna austenitu wysokostopowej stali austenitycznej AISI 304 poddanej procesowi uczulania oraz na próbkach odniesienia nie poddanych obróbce cieplnej.Badania LIS-AFM były...
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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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Photoactivity of decahedral TiO2 loaded with bimetallic nanoparticles: Degradation pathway of phenol-1- 13 C and hydroxyl radical formation
PublicationDecahedral 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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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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The enantiomeric determination of chloro-precursors of methamphetamine
PublicationImpurity profiling and classification of seized methamphetamine may supply valuable information with respect to the conditions and the chemicals used in the illicit methamphetamine manufacture and may provide information on the original source of the sample. Determination of the stereochemical makeup of forensic samples is important as well for the same reasons. Laboratories in many places are engaged in clandestine manufacture...
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Metal complexes with mixed s-donor ligands - a route via silanethiolates
PublicationW ramach prezentowanej pracy przedstawiono pierwsze próby syntezy mieszanych układów zawierających jednocześnie przykoordynowane reszty ditiokarbaminianową oraz silanotiolanowych. W badaniach posłużono się - jako substratami tri-tert-butoksysilanotiolanami kompleksami Cd, Zn, Cu, Pb, Hg, Ag i Co, a także solami kwasów: dietyloditiokarbaminowego oraz pirolidynoditiokarbaminowego. W przypadku związku Ag nie udało się wyizolować stałych...
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Mechanism of the reaction of Lawesson's reagent with N-alkylhydroxamic acids
PublicationIdentyfikacja fosforowych produktów powstających w reakcji kwasów hydroksamowych z odczynnikiem Lawessona pozwoliła ustalić mechanizm tytułowej reakcji. Wykorzystano w tym celu spektroskopię 31P NMR. Wzorce labilnych produktów otrzymano na niezależnej drodze syntetycznej lub przeprowadzono je w trwałe pochodne, które wyizolowano z mieszanin reakcyjnych. Produktem przejściowym badanej reakcji okazał się odpowiedni O-ditiofosfonylowany...
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Molecular mobility of water protons under interaction with chemically modified starches. DSC and HMR-relaxation investigations
PublicationThe change of water protons mobility in the system chemically modified starches – water were investigated by DSC and NMR-relaxation methods. The amount of unfrozen water at subzero temperature as well as additional unfrozen water which appears after gelatinization have lower values for chemically modified starches in comparison with the native starch. The proton spin-spin relaxation time Т2 for chemically modified starch samples,...
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Reactivity of bulky aminophosphanes towards small molecules: Activation of dihydrogen and carbon dioxide by aminophosphane/borane frustrated Lewis pairs
PublicationA series of mono- and bisaminophosphanes with formulas R2NPR’R’’ and (R2N)2PR’ (R = iPr, Cy; R’ = Ph, Cy; R’’ = iPr) were characterized by X-ray analysis, NMR spectroscopy and computational methods. The common structural futures of these species are short and polarized PAN bonds, a pyramidal geometry at the P atom and an almost planar geometry at the N atoms. According to DFT calculations, these...
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Comparison of the coordination geometries of Zn(II) and Cd(II) ions in complexes with water, methanol and bulky aryloxysilanethiolate ligands
PublicationZinc and cadmium complexes containing silanethiolate anions and methanol or water were synthesized and characterized by X-ray diffraction, FT-IR and NMR spectroscopy, and DFT calculations. Contrary to zinc, the cadmium ion utilizes very weak donors to complete its coordination sphere; it forms contacts to phenyl rings of the silanethiolate ligand. Two zinc analogs of the general formula [Zn{SSi(OAr)3}2(L)2] where L = CH3OH (2)...
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The Quaternization Reaction of 5-O-Sulfonates of Methyl 2,3-o-Isopropylidene-β-D-Ribofuranoside with Selected Heterocyclic and Aliphatic Amines
PublicationThe synthesis of N-((methyl 5-deoxy-2,3-O-isopropylidene-β-D-ribofuranoside)-5-yl) ammonium salts are presented. To determine the effect of the nucleophile type and outgoing group on the quaternization reaction, selected aliphatic and heterocyclic aromatic amines reacted with: methyl 2,3-O-isopropylidene-5-O-tosyl-β-D-ribofuranoside or methyl 2,3-O-isopropylidene-5-O-mesyl-β-D -ribofuranoside or methyl 2,3-O-isopropylidene-5-O-triflyl-β-D-ribofuranoside...
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Silicon Oxycarbide-Graphite Electrodes for High-Power Energy Storage Devices
PublicationHerein we present a study on polymer-derived silicon oxycarbide (SiOC)/graphite composites for a potential application as an electrode in high power energy storage devices, such as Lithium-Ion Capacitor (LIC). The composites were processed using high power ultrasound-assisted sol-gel synthesis followed by pyrolysis. The intensive sonication enhances gelation and drying process, improving the homogenous distribution of the graphitic...
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublicationIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...
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Products of Photo- and Thermochemical Rearrangement of 19-Membered di-tert-Butyl-Azoxybenzocrown
PublicationThe preparation and characterization of products of the photochemical and thermochemical rearrangements of 19-membered azoxybenzocrowns with two, bulky, tert-butyl substituents in benzene rings in the para positions to oligooxyethylene fragments (meta positions to azoxy group, i.e., t-Bu-19-Azo-O have been presented. In photochemical rearrangement, two colored typical products were expected, i.e., 19-membered o-hydroxy-m,m′-di-tert-butyl-azobenzocrown...
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In search of molecular precursors for cadmium sulfide-new complexes with a sulfur-rich kernel: cadmium(II) tri-tert-butoxysilanethiolates with additional diethyldithiocarbamato ligand
PublicationW ramach rozprawy opracowano metodę syntezy związków koordynacyjnych kadmu zawierających mieszane ligandy S-donorowe, które stanowią reszta tri-tert-butoksysilanotiolanowa oraz ditiokarbaminianowa. Zostały one poddane badaniom za pomocą analizy składu pierwiastkowego, metod spektroskopowych (FTIR, FIR, UV-Vis, NMR, MS) oraz termicznych. W celu osadzenia cienkich warstw wybranych związków posłużono się techniką nakładania obrotowego...
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The CON−H…+NH2 Blue-Shifting H-Bond Stabilizing Effect on Z Secondary Amides and Cyclic System Conformational Rearrangement through an Alkylamine-Chain Migration Pathway
PublicationThe paper is focusing on the amide linkage exceptional properties and usage of chemistry (conformational rearrangement, geometrical stereoisomers, spectroscopic blue shift phenomenon, protonation and deprotonation reactions, synthetic scope, and mechanistic implications). Hydrogen-bond-stabilized acylation reactions of a diamine with thioamides or nitriles reveal how substituents influence both the outcome of stereoselectivity...
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Design, synthesis and biological evaluation of novel N-phosphorylated and O-phosphorylated tacrine derivatives as potential drugs against Alzheimer’s disease
PublicationIn this work, we designed, synthesised and biologically investigated a novel series of 14N- and O-phosphorylated tacrine derivatives as potential anti-Alzheimer’s disease agents. In the reaction of 9-chlorotacrine and corresponding diamines/aminoalkylalcohol we obtained diamino and aminoalkylhydroxy tacrine derivatives. Next, the compounds were acid to give final products 6–13 and 16–21 that were characterised by 1H, 13 C, 31P...
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Preparation of Allyl Alcohol Oligomers Using Dipicolinate Oxovanadium(IV) Coordination Compound
PublicationCurrently, new precatalysts for olefin oligomerization are being sought in the group of vanadium(IV) complexes. Thus, the aim of our research was to examine the catalytic activity of the oxovanadium(IV) dipicolinate complex [VO(dipic)(H2O)2] 2 H2O (dipic = pyridine-2,6-dicarboxylate anion) in 2-propen-1-ol oligomerization as well as to characterize oligomerization products using matrix-assisted laser desorption/ionization–time-of-flight...
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Profiling of polar ionogenic metabolites in Polish wines by capillary electrophoresis-mass spectrometry
PublicationThe composition of wine is determined by a complex interaction between environmental factors, genetic factors (i.e., grape varieties), and winemaking practices (including technology and storage). Metabolomics using NMR spec-troscopy, GC-MS, and/or LC-MS has shown to be a useful approach for assessing the origin, authenticity, and quality of various wines. Nonetheless, the use of additional analytical techniques with complementary...
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First Copper(I) and Silver(I) Complexes Containing Phosphanylphosphido Ligands
PublicationThree new complexes with phosphanylphosphido ligands, [Cu4{μ2-P(SiMe3)-PtBu}4](1), [Ag4{μ2-P(SiMe3)-PtBu2}4](2) and [Cu{η1-P(SiMe3)-PiPr2}2]–[Li(Diglyme)2] (3) were synthesized and structurally characterized by X-ray diffraction, NMR spectroscopy, and elemental analysis. Complexes 1 and 2 were obtained in the reactionsof lithium derivative of diphosphane tBu2P-P(SiMe3)Li·2.7THF withCuCl and [iBu3PAgCl]4, respectively....
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Inactivation of glucosamine-6-phosphate synthase by N3-oxoacyl derivatives of L-2,3-diaminopropanoic acid
PublicationN3-oksoacylowe pochodne kwasu l-2,3-diaminopropanowego zawierające ugrupowanie epoksydowe lub układ sprzężonych wiązań podwójnych inaktywują syntaze glukozamino-6-fosforanu (GlcN-6-P) z S. cerevisiae. Wyniki badań kinetycznych inaktywacji enzymu wskazują na dwuetapowy przebieg tej reakcji, przy czym tworzenie kompleksu enzym:ligand poprzedza nieodwracalną modyfikację enzymu. Badane związki różniły się powinowactwem do centrum aktywnego...
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Syntheses, Structures and Reactivity of Terminal Phosphido Complexes of Iron(II) Supported by a β-Diketiminato Ligand
PublicationWe report the synthesis of the first series of terminal phosphido iron complexes supported by a β‐diketiminato ligand (Dippnacnac) and their catalytic activity in dehydrocoupling of secondary phosphines. Anionic and neutral mono‐ or diphosphido complexes were obtained from the reaction of [(Dippnacnac)FeCl2Li(dme)2] with the R2PLi (R = iPr, tBu, Cy, Ph) phosphides by tuning the stoichiometric ratio, polarity of the solvent, and...
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Preparation and Characterization of Nanomaterial Consisting of Silica Aerogel & Carbon Tested as an Electrode in Non-Aqueous Media Containing Lithium Salt.
PublicationSilica aerogel (SiO2ag) was combined with carbonaceous material in the pyrolysis process of hydrocarbons. The obtained nanocomposite SiO2ag/C was amorphous, partially preserving the porous structure of SiO2ag. The specific surface area changes from 445.6 m2/g for pure SiO2ag to 205.52 m2/g SiO2ag/C. The 29Si MAS-NMR shows a three-dimensional matrix with silicon atoms connected to other silicon atoms by four...
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Kompleksy fosfanylofosfidowe z grupami indenylowymi
PublicationPochodne litowe difosfanów są z powodzeniem stosowane jako prekursory ligandów fosfanylofosfinidenowego R2PP oraz fosfanylofosfidowego R2PP(SiMe3) w reakcjach z dichlorometalocenami. Rodzaj powstałych produktów w tego typu reakcjach, w dużej mierze zależy od podstawników w pierścieniu cyklopentadienylowym w cząsteczce metalocenu oraz od właściwości atomu metalu. Zastosowanie dichlorocyrkonocenów z grupami indenylowymi (Ind=C9H7)...
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Podstawy chemii fizycznej i biofizycznej -- ćwiczenia
e-Learning CoursesCelem przedmiotu jest dostarczenie formalizmu służącego do opisu i przewidywania przebiegu reakcji biochemicznych oraz innych procesów biomolekularnych. Plan kursu: 1. Oddziaływania międzycząsteczkowe (elektrostatyka, oddziały-wania van der Waalsa, wiązania wodorowe, oddziaływania hydro-fobowe) 2. Podstawy termodynamiki z elementami teorii statystycznej (zasady termodynamiki, entropia i jej interpretacja statystyczna, rozkład...
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Podstawy chemii fizycznej i biofizycznej -- wykład
e-Learning CoursesCelem przedmiotu jest dostarczenie formalizmu służącego do opisu i przewidywania przebiegu reakcji biochemicznych oraz innych procesów biomolekularnych. Plan kursu: 1. Oddziaływania międzycząsteczkowe (elektrostatyka, oddziały-wania van der Waalsa, wiązania wodorowe, oddziaływania hydro-fobowe) 2. Podstawy termodynamiki z elementami teorii statystycznej (zasady termodynamiki, entropia i jej interpretacja statystyczna, rozkład...
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Metody elektrochemiczne w zastosowaniach biomedycznych 2022/2023
e-Learning CoursesPRZEDMIOT OBEJMUJE: WYKŁAD, LABORATORIUM, PROJEKT Treści wykładu Podstawy elektrochemii, elektryczna warstwa podwójna metal /elektrolit, półprzewodnik elektrolit. Kinetykaprocesów elektrodowych. Elektrokataliza. Podstawy metod pomiarowych: woltamperometria,chronoamperometria, elektrochemiczna spektroskopia impedancyjna. Wykorzystanie metodelektrochemicznych w projektowaniu sensorów w zastosowaniach biomedycznych. Biokompatybilnośćmateriałów...
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The influence of amorphous macrodiol, diisocyanate type and l-ascorbic acid modifier on chemical structure, morphology and degradation behavior of polyurethanes for tissue scaffolds fabrication
PublicationStudies described in this work were related to the bulk synthesis and characterization of polyurethanes (PURs) obtained with the use of cyclic 4,4′-methylene bis(cyclohexyl isocyanate) (HMDI) or linear 1,6-hexamethylene diisocyanate (HDI), amorphous α,ω-dihydroxy(ethylene-butylene adipate) macrodiol (PEBA), 1,4-butandiol (BDO) chain extender and dibutyltin dilaurate (DBTDL) catalyst. Obtained PURs were modified with l-ascorbic...
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Properties of LiMnBO3 glasses and nanostructured glass-ceramics
PublicationPolycrystalline LiMnBO3 is a promising cathode material for Li-ion batteries. In this work, we investigated the thermal, structural and electrical properties of glassy and nanocrystallized materials having the same chemical composition. The original glass was obtained via a standard melt-quenching method. SEM and 7Li solid-state NMR indicate that it contains a mixture of two distinct glassy phases. The results suggest that the...
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π-Stacking attraction vs. electrostatic repulsion: competing supramolecular interactions in a tpphz-bridged Ru(ii)/Au(iii) complex
PublicationThe synthesis and characterization of a mixed metal ruthenium(II)/gold(III) complex bridged by tetrapyridophenazine (tpphz) are described. It is isostructural and isoelectronic to the well-known photocatalysts with palladium(II) or platinum(II). Concentration dependent 1H-NMR spectroscopy and XRD studies show that the electrostatic repulsion between the gold(III) moieties exceeds the attractive π-stacking interaction. Theoretical...
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Hydrazinolysis Products of Selected Sugar Lactones—Crystal Structure and Microbiological Activity
PublicationCommercially available lactones, as well as those synthesized by us, turned out to be good substrates for the synthesis of sugar hydrazides. The exception was L-ascorbic acid, whose hydrazinolysis led to the formation of a hydrazinium salt, not the hydrazide as expected. The structure of all compounds was confirmed by NMR and X-ray analyses. The lower durability of hydrazinium L-ascorbate was additionally confirmed by thermogravimetric...
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Metody Badań Strukturalnych Związków Organicznych
e-Learning CoursesGłównym celem wykładu jest nauczenie słuchaczy interpretacji widm z wykorzystaniem synergizmu informacji dostarczanych przez spektroskopie NMR, IR, elektronową oraz spektrometrię mas.Techniki spektroskopowe wykorzystują promieniowanie elektromagnetyczne o różnej energii, a widma są odpowiedzią badanego związku na zastosowane promieniowanie. W treściach wykładu zostaną przedstawione:(1) podstawy teorii i sposoby rejestracji widm...
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Systematic Study of Hydration Patterns of Phosphoric(V) Acid and Its Mono-, Di-, and Tripotassium Salts in Aqueous Solution
PublicationSpektroskopia oscylacyjna FTIR w zakresie drgania OD cząsteczki HDO została zastosowana do zbadania różnych form fosforanów w kolejności malejącego stopnia protonacji: H3PO4, KH2PO4, K2HPO4, K3PO4. HDO rozcieńczona izotopowo w H2O została otrzymana przez dodanie odpowiednich ilości wody ciężkiej (D2O) do roztworów w wodzie zwykłej. Do wyizolowania widm HDO zaburzonej przez substancję rozpuszczoną zastosowano metodę widm różnicowych....
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Novel decahedral TiO2 photocatalysts modified with Ru or Rh NPs: Insight into the mechanism
PublicationNovel decahedral TiO2 modified with Ru or Rh NPs were successfully synthesized by hydrothermal method. The effect of metal type as well as amount of noble metal precursor (0.05, 0.1, 0.2, 0.3 and 0.5 wt.%) on the photocatalytic activity were investigated. Decahedral TiO2 decorated by Ru and Rh nanoparticles was prepared by photodeposition method, whereas Rh doped TiO2 was obtained by onestep hydrothermal method with introduction...
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Badanie mieszanek łoju wołowego z ciekłym lub uwodornionym olejem rzepakowym.
PublicationZbadano właściwości fizyczne mieszanek łoju wołowego z ciekłym lub uwodornionym olejem rzepakowym o różnym składzie procentowym. Oznaczano zawartość fazy stałej metodą NMR, stosując różne metody termostatowania badanych tłuszczów przed analizą. Charakterystyki topnienia wyznaczono metodą DSC. Przed wyznaczeniem krzywych topnienia stosowano takie same etapy termostatowania jak przed oznaczeniem zawartości fazy stałej. W mieszankach...
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Lower rim substituted tert-butylcalix[4]arenes.Part 8: Calix[4]arenes with dialkoxyphosphoryl functions. Synthesis and complexing properties
PublicationW pracy przedstawiono syntezę i charakterystykę otrzymanych związków (1, 2), pochodnych alkoksyfosforylowych p-tert-butylokaliks[4]arenu: 5,11,17,23-tetra-tert-butylo-25,26,27,28-tetrakis(3-diizopropoksyfosforylopropoksy)kaliks[4]arenu (1) oraz 5,11,17,23-tetra-tert-butylo-25,26,27,28-tetrakis(3-methoksyetoksyfosforylopropoksy)kaliks[4]arenu (2). Zbadano właściwości jonoforowe związków 1 i 2 w membranie elektrod jonoselektywnych,...
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Analytical studies on ascosin, candicidin and levorin multicomponent antifungal antibiotic complexes. The stereostructure of ascosin A2
PublicationIn the class of polyene macrolides, there is a subgroup of aromatic heptaenes, which exhibit the highest antifungal activity within this type of antibiotics. Yet, due to their complex nature, aromatic heptaenes were not extensively studied and their potential as drugs is currently underexploited. Moreover, there are many inconsistencies in the literature regarding the composition and the structures of the individual components...
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Structure analysis and thermal degradation characteristics of bio-based poly(propylene succinate)s obtained by using different catalyst amounts
PublicationLinear bio-based polyester polyols were prepared with the use of succinic acid and 1.3-propanediol (both with natural origin). As a catalyst was used tetraisopropyl orthotitanate (TPT). In order to determine the effect of various catalyst content on the thermal degradation characteristics, three different TPT amounts, as a 1.3-propanediol equivalent, were used, namely 0.1 mass% (PPS-0.1), 0.2 mass% (PPS-0.2) and 0.25 mass% (PPS-0.25)....
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New insights on lithium storage in silicon oxycarbide/carbon composites: Impact of microstructure on electrochemical properties
PublicationIn this work, we study the impact of the preceramic precursor vinyltriethoxysilane (VTES) on the electrochemical performance of silicon oxycarbide (SiOC) glass/graphite composites. We apply an innovative approach based on high-power ultrasounds in order to obtain highly homogenous composites with a uniform distribution of small graphitic flakes. This procedure enhances gelation and drying of VTES-based preceramic polymer/graphite...
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Symmetrical and unsymmetrical diphosphanes with diversified alkyl, aryl and amino substituents
PublicationWe present the comprehensive study of diphosphanes with diversified substituents regarding their syntheses, structures, and properties. To this end, we have synthesized a series of novel unsymmetrical alkyl, aryl and amino-substituted diphosphanes of the general formula R1R2P-PR3R4 (where R1, R2, R3, R4 = tBu, Ph, Et2N or iPr2N) via salt metathesis reactionof halophosphanes with metal phosphides in high yield. We vastly expanded...
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Reactivity of Phosphanylphosphinidene Complex of Tungsten(VI) toward Phosphines: A New Method of Synthesis of catena-Polyphosphorus Ligands
PublicationThe reactivity of an anionic phosphanylphosphinidene complex of tungsten(VI), [(2,6-i-Pr2C6H3N)2(Cl)- W(η2-t-Bu2P=P)]Li·3DME toward PMe3, halogenophosphines, and iodine was investigated. Reaction of the starting complex with Me3P led to formation of a new neutral phosphanylphosphinidene complex, [( 2,6-i-Pr2C6H3N)2(Me3P)W(η2-t-Bu2P=P)]. Reactions with halogenophosphines yielded new catena-phosphorus complexes. From reaction with...