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91.
Fabiana Quaglia Giuseppe Fusco Giuseppe De Rosa Francesca Ungaro Agnese Miro Maria Immacolata La Rotonda 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):669-674
The aim of this work was to produce lycopene-containing powders from tomato products by a solvent-free method making use of
β-cyclodextrin (βCD). Powders were prepared by spray-drying a tomato concentrate (TC), one of the most bioavailable form of
lycopene, after mechanical treatment with βCD in different weight ratios. The obtained product was centrifuged to eliminate
partly food matrix and characterized for the amount of lycopene hydrodispersed/hydrosolubilized in the aqueous fraction. The
chemical antioxidant activity of sera was evaluated too. Powders obtained by spray-drying sera exhibited good flow properties,
a lycopene content between 0.4 and 1.09 mg/g and excellent water dispersability. The process developed, which makes use of
βCD for the treatment of tomato products, turns to be of great interest to obtain a bulk material for nutraceuticals displaying
superior biovailability of lycopene. 相似文献
92.
93.
Palombo F Paolantoni M Sassi P Morresi A Giorgini MG 《Physical chemistry chemical physics : PCCP》2011,13(36):16197-16207
Slow to ultrafast dynamics of liquid acetone at variable temperature was investigated by depolarized Rayleigh and low-frequency Raman scattering spectroscopy, in the region 0-200 cm(-1). A detailed analysis was performed on the spectra and corresponding time responses, and a consistent view of the molecular dynamics of this dipolar solvent was obtained. The effects of temperature on the spectra were interpreted, and distinct dynamical processes identified. At very low frequencies, or long time scales, acetone dynamics is characterized by a slow diffusive reorientation obeying the Stokes-Einstein-Debye hydrodynamic theory only in the limit of subslip boundary conditions. An alternative model based on the microviscosity concept proved to be able to reproduce this correlation time and its temperature dependence. A comparative analysis of collective and single-molecule reorientational times, these latter estimated from intramolecular Raman spectra, led to an orientational correlation parameter g(2) of unity, which denotes a statistical disorder of molecular polarizability tensors. A fast local restructuring process is putatively responsible for an additional contribution at subpicosecond time scales often referred to as intermediate response in other molecular liquids. The high frequency portion of the dynamical susceptibility showed the signature of librational intermolecular motions, giving rise to an ultrafast decay of the time correlation function of polarizability anisotropy. The overall approach, which provided valuable information on dynamics, structure and molecular interactions of neat acetone, will be applied to acetone electrolytic solutions. 相似文献
94.
Morra S Valetti F Sadeghi SJ King PW Meyer T Gilardi G 《Chemical communications (Cambridge, England)》2011,47(38):10566-10568
[FeFe]-hydrogenases are efficient natural catalysts that can be exploited for hydrogen production. Immobilization of the recombinant [FeFe]-hydrogenase CaHydA was achieved for the first time on an anatase TiO(2) electrode. The enzyme is able to interact and exchange electrons with the electrode and to catalyze hydrogen production with an efficiency of 70%. 相似文献
95.
Patrizia Scafato Francesca Caprioli Laura Pisani Daniele Padula Fabrizio Santoro Giuseppe Mazzeo Sergio Abbate France Lebon Giovanna Longhi 《Tetrahedron》2013
Three forms of chiroptical spectroscopies, electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and optical rotatory dispersion (ORD) have been employed to study the configuration and conformational properties of the three molecules: (S)-3-phenylcyclopentanone, (S)-3-phenylcyclohexanone, and (S)-3-phenylcycloheptanone (including (S)-3-phenylcyclopentanone-2,2,5,5-d4 and (S)-3-phenylcyclohexanone-2,2,6,6-d4). ECD and VCD spectra in the mid-IR for the three molecular systems are marginally dependent on fine conformational details, as interpreted in terms of standard DFT computational methods, with common spectroscopic features to the three systems clearly identified. Accounting for vibronic coupling mechanisms reproduces the structuring of ECD n→π∗ band. The ORD curves are quite similar for the three types of molecules, but their interpretation highlights a crucial role played by conformations of the cycloalkanone ring in the case of (S)-3-phenylcycloheptanone. The same conclusions are reached by considering the VCD spectra in the CH-stretching region. 相似文献
96.
97.
Gabriele Albertin Stefano Antoniutti Jesús Castro Francesca Sibilla 《无机化学与普通化学杂志》2019,645(8):638-644
Imine complexes [IrCl(η5‐C5Me5){κ1‐NH=C(H)Ar}{P(OR)3}]BPh4 ( 1 , 2 ) (Ar = C6H5, 4‐CH3C6H4; R = Me, Et) were prepared by allowing chloro complexes [IrCl2(η5‐C5Me5){P(OR)3}] to react with benzyl azides ArCH2N3. Bis(imine) complexes [Ir(η5‐C5Me5){κ1‐NH=C(H)Ar}2{P(OR)3}](BPh4)2 ( 3 , 4 ) were also prepared by reacting [IrCl2(η5‐C5Me5){P(OR)3}] first with AgOTf and then with benzyl azide. Depending on the experimental conditions, treatment of the dinuclear complex [IrCl2(η5‐C5Me5)]2 with benzyl azide yielded mono‐ [IrCl2(η5‐C5Me5){κ1‐NH=C(H)Ar}] ( 5 ) and bis‐[IrCl(η5‐C5Me5){κ1‐NH=C(H)Ar}2]BPh4 ( 6 ) imine derivatives. In contrast, treatment of chloro complexes [IrCl2(η5‐C5Me5){P(OR)3}] with phenyl azide C6H5N3 gave amine derivatives [IrCl(η5‐C5Me5)(C6H5NH2){P(OR)3}]BPh4 ( 7 , 8 ). The complexes were characterized spectroscopically (IR, NMR) and by X‐ray crystal structure determination of [IrCl(η5‐C5Me5){κ1‐NH=C(H)C6H4‐4‐CH3}{P(OEt)3}]BPh4 ( 2b ). 相似文献
98.
Fabio D’Agostino Elvira Oliveri Emanuela Bagnato Francesca Falco Salvatore Mazzola Mario Sprovieri 《Analytica chimica acta》2014
The aim of this work was to develop a new method to determine the mercury (Hg) concentrations in phosphate rock using a dedicated analytical instrument (the DMA80 Tricell by Milestone) that employs an integrated sequence of thermal decomposition followed by catalyst conversion, amalgamation and atomic absorption spectrophotometry. However, this instrument underestimates Hg concentrations when phosphorite and apatite rocks are investigated with a classic thermal decomposition treatment that complies with US EPA method 7473. 相似文献
99.
Francesca Benedini Giorgio Bertolini Francesco Ferrario Angelo Motti Alberto Sala Flavio Somenzi 《Journal of heterocyclic chemistry》1995,32(1):103-107
The preparation and the physico-chemical characterization of 2H-pyrido[2,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazin-4(3H)-ones, 2H-thieno[2,3-e]-1,3-oxazin-4(3H)-ones and 2H-thieno[3,4-e]-1,3-oxazine-2,4(3H)-diones are reported. 相似文献
100.
Eslava S Baklanov MR Kirschhock CE Iacopi F Aldea S Maex K Martens JA 《Langmuir : the ACS journal of surfaces and colloids》2007,23(26):12811-12816
Ellipsometric porosimetry was used to determine the adsorption isotherms of toluene, methanol, and water on b-oriented Silicalite-1 coatings with a thickness of less than ca. 250 nm and to obtain adsorption kinetics. The adsorption isotherms are of sufficient quality to reveal several aspects of the pore structure such as the adsorbate capacity and the adsorbate/framework affinity. The use of a combination of different molecular probes in ellipsometric porosimetry to elucidate the molecular accessibility of Silicalite-1 pores is demonstrated. It is shown that ellipsometric porosimetry is an appropriate technique for probing the influence of aging of the Silicalite-1 coating and of planarization polishing on the porosity, pore accessibility, and adsorbate/framework affinity. 相似文献