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61.
Mohammed Ahmed Shehab Nikita Sharma Andrea Valsesia Gbor Karacs Ferenc Kristly Tams Kos Anett Katalin Lesk Lilla Nnai Klara Hernadi Zoltn Nmeth 《Molecules (Basel, Switzerland)》2022,27(9)
Nowadays, the use of hybrid structures and multi-component materials is gaining ground in the fields of environmental protection, water treatment and removal of organic pollutants. This study describes promising, cheap and photoactive self-supported hybrid membranes as a possible solution for wastewater treatment applications. In the course of this research work, the photocatalytic performance of titania nanowire (TiO2 NW)-based hybrid membranes in the adsorption and degradation of methylene blue (MB) under UV irradiation was investigated. Characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffractometry (XRD) were used to study the morphology and surface of the as-prepared hybrid membranes. We tested the photocatalytic efficiency of the as-prepared membranes in decomposing methylene blue (MB) under UV light irradiation. The hybrid membranes achieved the removal of MB with a degradation efficiency of 90% in 60 min. The high efficiency can be attributed to the presence of binary components in the membrane that enhanced both the adsorption capability and the photocatalytic ability of the membranes. The results obtained suggest that multicomponent hybrid membranes could be promising candidates for future photocatalysis-based water treatment technologies that also take into account the principles of circular economy. 相似文献
62.
Dalma Czett Katalin Bddi Veronika Nagy Anik Taktsy Jzsef Deli Paul Tone Gyrgy T. Balogh Anna Vincze Attila Agcs 《Molecules (Basel, Switzerland)》2022,27(15)
Carotenoid succinates were synthesized from hydroxy carotenoids and were coupled to a commercially available derivative of melatonin via amide bond for producing more powerful anti-oxidants and yet new hybrid lipophilic bifunctional molecules with additional therapeutic effects. The coupling reactions produced conjugates in acceptable to good yields. Succinylation increased the water solubility of the carotenoids, while the conjugation with melatonin resulted in more lipophilic derivatives. The conjugates showed self-assembly in aqueous medium and yielded relatively stable colloidal solutions in phosphate-buffered saline. Antioxidant behavior was measured with ABTS and the FRAP methods for the carotenoids, the carotenoid succinates, and the conjugates with melatonin. A strong dependence on the quality of the solvent was observed. TEAC values of the new derivatives in phosphate-buffered saline were found to be comparable to or higher than those of parent carotenoids, however, synergism was observed only in FRAP assays. 相似文献
63.
Du
an Uhrín Gyula Batta Victor J. Hruby Paul N. Barlow Katalin E. Kvr 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1998,130(2)
An enhanced version of the X(ω1) half-filtered TOCSY experiment for measurement of long-range heteronuclear coupling constants is proposed which yields high-quality spectra with substantially increased sensitivity and resolution. The modified method features gradient-enhanced X filtering sequences, broadband homonuclear decoupling duringt1, optional1JXHscaling in theF1domain, and gradient coherence selection in combination with the sensitivity-enhanced protocol for the TOCSY transfer. These modifications extend the applicability of the method—coupling constants can be measured accurately for natural abundance samples at low concentrations and for compounds yielding complex spectra. Computer-aided analysis of E.COSY-type multiplets is applied for the determination of heteronuclear long-range coupling constants. 相似文献
64.
The Dirac Hamiltonian is calculated in the Schwarzschild space and compared to the analogous one in a uniformly accelerating Minkowski frame yielding a test of the equivalence principle. Comparing these Hamiltonians, we see that the flat-space energy-mass terms and their redshifted forms are the same in the two cases, but the coefficient of the spin-orbit coupling term is different and an additional term appears in the gravitational case. 相似文献
65.
Queite A. de Paula Jean-Pierre Joly Katalin Selmeczi David E. P. Fonseca Giovanni F. Caramori Nicholas P. Farrell 《Journal of Coordination Chemistry》2018,71(11-13):1894-1909
AbstractTwo copper(II) complexes with tetradentate 1,4-disubstituted-1,2,3-triazole ligands, [CuL(MeCN)](ClO4)2 (1) and [CuL′](ClO4)2 (2), have been prepared and characterized by different techniques, including X-ray structure determination, spectroscopic, and electrochemical measurements, as reported elsewhere. Herein, we report the interactions of these complexes, and corresponding free ligands, with human serum albumin (HSA) verifying their relative thermodynamic stability and differences in binding to this protein. Interactions with HSA were verified by CD measurements monitored at 564?nm, up to stoichiometric ratio 2:1 [Complex]:[protein], according to competitive equilibria involving the insertion of copper at the selective N-terminal metal binding site in HSA, and additionally at a secondary nonselective site. Further interactions of these complexes with L-tryptophan residues, and probable supplementary site(s) for the binding, were followed by fluorescence measurements. Analogous experiments with the free L and L′ indicated much weaker interactions. Protein oxidation damage was observed for both complexes, monitored by carbonyl groups formation in the presence of H2O2, probably with the participation of reactive oxygen species. Density functional theory calculations exhibit metal-ligand binding interaction energies similar to [Cu(HSA-Nterminal)]+, and reinforced the experimental results, showing clearly that such triazole ligands are competitive toward copper(II) in biological medium. 相似文献
66.
Katalin A. Föglein Irina Babievskaya Pál T. Szabó János Szépvölygi 《Plasma Chemistry and Plasma Processing》2003,23(2):233-243
Thermal decomposition of volatile organic compounds (VOCs) such as n-hexane and toluene has been studied in an inductively coupled thermal plasma reactor, at atmospheric pressure, in neutral and oxidative conditions, respectively. Thermodynamic calculations were performed for predicting the product distribution due to thermal decomposition. Based on these calculations formation of the products observed in the gas phase and in the extract of soot could be interpreted. In neutral conditions formation of soot and PAH was detected to different extent for the different models. The presence of oxygen in the plasma reactor depresses both soot and PAH formation. GC-MS analyses of the gaseous products and the extract of the soot, respectively, refer to as complex decomposition and recombination mechanism in given conditions. 相似文献
67.
Katalin Nemák Mária Ács D. Kozma E. Fogassy 《Journal of Thermal Analysis and Calorimetry》1997,48(3):691-696
The phenomena of conglomerate formation-racemic compound formation were investigated in a series of five (N-alkyl)-2,6-pipecoloxylidides. The optically active enantiomers were prepared by optical resolution of the racemates using 2R,3R-tartaric acid and 0,0-dibenzoyl-2R,3R-tartaric acid as resolving agent. By DSC measurement of the racemates and the enantiomer the binary phase diagrams were determined.Among the four racemic molecular compounds the N-methyl derivative is the more stable. By increasing the length of the alkyl chain the stability of the racemic compound decreased, and in case of the longest -butyl-chain conglomerate formation was observed.Part 3. D. Kozma, Zs. Böcskei, Cs. Kassai, K. Simon and E. Fogassy: Racemic Compound Formation-Conglomerate Formation. Part 3. Investigation of the Acidic Salts of -phenylethylamine by Achiral Dicarboxylic Acids. Optical Resolution by Preferential Crystallization and a Structural Study of R--phenylethylammonium hydrogen ithaconate, J. Chem. Soc. Perkin Trans. 2 (1996) 1511.The authors are grateful for financial support to OTKA foundation (grant numbers: F14851 (D. K.), T14887 (E. F.)) and for the Z. Magyary award for D. K. 相似文献
68.
69.
JPC – Journal of Planar Chromatography – Modern TLC - A pilot study has been conducted to develop sample preparation procedure and TLC separation of radiolabeled metabolites of an AMPA... 相似文献
70.
Ž. K. Jaćimović V. M. Leovac G. Giester Z. D. Tomić Katalin Mészáros Szécsényi 《Journal of Thermal Analysis and Calorimetry》2007,90(2):549-555
In the
scope of design and optimise the equipment for alcoholic distillate beverages
production, a sufficient knowledge of physical properties and phase equilibria
is necessary. In this paper we present the temperature dependence of excess
molar volumes of the ternary system ethanol+water+1-propanol at the range
288.15–323.15 K and atmospheric pressure, due to the importance of the
1-propanol among the flavour compounds contained into this type of beverages.
Derived properties were computed due to its importance in the study of specific
molecular interactions. 相似文献