Scopul nostru este sprijinirea şi promovarea cercetării ştiinţifice şi facilitarea comunicării între cercetătorii români din întreaga lume.
The complexation of β-cyclodextnn (βCD) and quercetin (Que) in aqueous alcoholic solutions is investigated by UV-Vis spectroscopy. Three different aqueous media, namely pH 3, unbuffered (pH 5.5) and pH 7, are used to vary the environmental conditions and the interaction between host (βCD) and guest (Que) molecules. The equilibrium constants for the formation of the inclusion βCD-Que complex are estimated from two different absorption bands and
Read moreThe behaviour of cholesterol (CHO) and dimyristoyl phosphatidylcholine (DMPC), as well as of their mixed monolayers of various compositions has been investigated by surface potential (δV) measurements at the air/water interface for different surface pressures, using Langmuir technique coupled with the vibrating plate method. Isotherms of δV versus mean molecular area, A, at different cholesterol mole fractions, xCHO, were recorded, and δV versus
Read moreAn aqueous colloid dispersion of gold nanoparticles (AuNPs) was prepared by reduction of gold(III) chloride and its interaction with three local anesthetics (procaine, dibucaine or tetracaine) was investigated. Optical spectra reveal the modifications in the absorption band of nanoparticles related to their self assembly mediated by anesthetic molecules and depending on the progress in time of the aggregation process. TEM images show the features
Read moreSilver nanoparticles (AgNPs) were prepared in aqueous colloid dispersions by the reduction of Ag+ with glucose in alkaline medium. Tetraethyl orthosilicate and l-asparagine were added as stabilizers of NPs. The AgNPs were characterized, and their interaction with three local anesthetics (procaine, dibucaine, or tetracaine) was investigated. Optical spectra show the characteristic absorption band of AgNPs, due to surface plasmon resonance. Modifications
Read moreA biogenic approach for the synthesis of gold nanoparticles (GNPs) by reducing chloroauric acid (HAuCl4) with three different plant extracts (from Angelica, Hypericum, and Hamamelis) is described. The content of reducing compounds (polyphenols) in each plant extract was determined by photometric dosing. The formation of GNPs was tracked by ultraviolet-visible spectroscopy and their characterization was performed using transmission electron microscopy
Read moreWe investigate the changes of the fractions of flow units and free volumes in two typical metallic glasses by variation of their preparation cooling rates. It is found that the fractions of the flow units and the free volumes show a similar dependence on the cooling rate, which is suggestive of the existence of a strong connection between them. The microstructural correlation between flow units and free volumes of the metallic glasses is discussed,
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