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I. Chereji L. Daraban S. Dreve S. Boscaneanu C. Cosma E. Vari 《Journal of Radioanalytical and Nuclear Chemistry》1996,212(2):85-92
The cesium rarioactivity (owing to134Cs and137Cs) in a number of wild plants of phamaceutical interest harvested in Transylvania was followed during the 1986–1994 period. The data give information on major pathways of vegetable organism contamination through lives from fallout and resuspention and by root uptake from contaminated soil. 相似文献
33.
Petrella A Tamborra M Curri ML Cosma P Striccoli M Cozzoli PD Agostiano A 《The journal of physical chemistry. B》2005,109(4):1554-1562
An extensive optical and photoelectrochemical study of blended systems composed of organic-capped TiO(2) nanocrystals with either a spherical or rodlike morphology and a conjugated polymer, MEH-PPV, is presented. The absorption and emission properties of the heterojunctions have been characterized both in solution and in thin films. The blended structures deposited onto conductive substrates have been employed as active layers in photoelectrochemical systems. The investigation has been focused on the photoinduced charge transfer and recombination processes at the interface between the two components, as a function of the nanocrystal shape and surface coating, and of the film thickness. The presence of a large number of interfaces available for charge transfer is believed to play a fundamental role in enhancing the photoelectrochemical performances of the dispersed heterojunctions. The reported results suggest that such MEH-PPV/TiO(2) heterojunctions may be exploited as potential active layers in future photovoltaic and photoelectrochemical devices. 相似文献
34.
Twenty ancient silver coins have been analyzed by the X-ray fluorescence method. For eliminating the effects that disturb the absolute quantitative measurements, we calculated, for each coin, the ratio between the elements that constitute the coin and related them to the silver concentration. From these measurements correlation diagrams have been obtained in which coins are grouped together depending on the silver sources and the purification technologies. 相似文献
35.
An X-ray diffraction method is presented capable of determining the average particle size, microstrains, the probability of faults as well as a particle size distribution function in crystalline materials. The method is based on the Fourier analysis of a single X-ray diffraction profile. Results obtained on supported platinum catalysts used in H/D isotopic exchange reactions are reported. On the basis of experimental spectra and our XRLINE1 code all structural parameters could be obtained. 相似文献
36.
Agostiano A. Catucci L. Castagnolo M. Colangelo D. Cosma P. Fini P. Della Monica M. 《Journal of Thermal Analysis and Calorimetry》2002,70(1):115-122
Cyclodextrins (CDs) are widely used as delivery systems of poorly water soluble drugs in pharmacological applications. The
delivery system produces an increase of aqueous solubility of the drug and significant modifications in its physico-chemical
and pharmacological properties. In this paper we report the results of our study on aqueous solutions of chlorophyll a, a
natural pigment useful as sensitizer in the photodynamic therapy, and two CDs: hydroxypropyl- b-cyclodextrin and heptakis(2,6-di-O-methyl)-b-cyclodextrin.
The interactions between chlorophyll and CDs and the effect produced by the presence of the CDs on the aggregation of chlorophyll
were studied by calorimetric and UV-Vis spectrophotometric measurements respectively.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Cosma P Catucci L Fini P Dentuto PL Agostiano A Angelini N Scolaro LM 《Photochemistry and photobiology》2006,82(2):563-569
The formation of inclusion complexes of hydroxypropyl-beta-cyclodextrin, heptakis(2,6-di-O-methyl)-beta-cyclodextrin and heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin with 5,10,15,20-tetrakis(4-pyridyl)porphyrin (TpyP) has been studied in aqueous buffer solution (phosphate buffer pH = 7 and I = 0.01 M) to give a structural and spectroscopic characterization of a new class of potential sensitizers for photodynamic therapy. The interaction was investigated by a combination of UV/Vis absorption, fluorescence anisotropy, time-resolved fluorescence and circular dichroism. The experimental results point to the presence of the pigment in water in a monomeric complexed form. The fluorescence anisotropy measurements suggest that TpyP forms 1:1 complexes with heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin and hydroxypropyl-beta-cyclodextrin, while 1:2 complexes are obtained with heptakis(2,6-di-O-methyl)-beta-cyclodextrin. 相似文献
39.
Dentuto P. L. Castagnolo M. Catucci L. Cosma P. Fini P. Agostiano A. 《Journal of Thermal Analysis and Calorimetry》2004,77(2):437-444
The interactions between Chlorophyllide a (Chlide), a pigment having the same structure of Chl a without the phytilic tail, and two CDs having the same moieties but different cavity size, the hydroxypropyl- β -cyclodextrin
and the hydroxypropyl-γ-cyclodextrin, were studied in aqueous solutions by means of absorption, fluorescence spectroscopy,
circular dichroism and isothermal titration calorimetry. The results obtained indicate that both cyclodextrins are able to
modify the aggregation equilibrium of the pigment favouring the monomeric form.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
40.
Ventrella Andrea Verrone Raffaella Cosma Pinalysa Fini Paola Longobardi Francesco Lippolis Vincenzo Pascale Michelangelo Catucci Lucia 《Journal of solution chemistry》2014,43(8):1436-1447
Journal of Solution Chemistry - The interaction of ochratoxin A (OTA) with heptakis-2,6-di-O-methyl-β-cyclodextrin (DIMEB) in aqueous solutions at two different pHs (3.5 and 9.5) was studied... 相似文献