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Comment: 6 pages including 2 figures -- Two appendices contain material that is not in the Journal version: A) Derivation of the fluctuation relation; B) Symmetry point of the generating function
The nature and strength of interaction of pyrrole adsorbed in alkali metal cation-exchanged faujasites have been investigated by the combined use of different surface vibrational techniques, X-ray diffraction and temperature-programmed desorption accompanied by theoretical studies. The results obtained depend on the kind of cation, the degree of ion exchange and the Si/Al ratio of the zeolites, indicating that the effective strength of interaction depends on both the Lewis acidic properties of the extraframework cations and the Lewis basic properties of the lattice oxygen atoms. It was found that pyrrole is adsorbed due to these two different kinds of interactions which occur parallel and influence each other: pyrrole is bound via the NH group to the lattice oxygen atoms by hydrogen bonding and, simultaneously, via the aromatic system ...
The nature and strength of interaction of methylated pyrrole derivatives (N-methylpyrrole, 2-methylpyrrole and 2,5-dimethylpyrrole) adsorbed in alkali metal cation-exchanged faujasites have been investigated by the joint use of temperature-programmed desorption (TPD), infrared spectroscopy and X-ray diffraction accompanied by quantum mechanical studies. It was found that successive methylation of pyrrole leads to an enhancement of the electron donor properties by which the effective strength of interaction can be subtly tuned. However, a complex adsorption behaviour dependent on the kind of cation, the degree of ion exchange and the Si/Al ratio of the zeolites was observed. The results indicate that obviously different kinds of interaction occur simultaneously. To discriminate between different adsorption sites of the probes the experi...
BACKGROUND/OBJECTIVES: Phytoestrogens are estradiol-like natural compounds found in plants that have been associated with protective effects against chronic diseases, including some cancers, cardiovascular diseases and osteoporosis. The purpose of this study was to estimate the dietary intake of phytoestrogens, identify their food sources and their association with lifestyle factors in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. SUBJECTS/METHODS: Single 24-hour dietary recalls were collected from 36 037 individuals from 10 European countries, aged 35–74 years using a standardized computerized interview programe (EPIC-Soft). An ad hoc food composition database on phytoestrogens (isoflavones, lignans, coumestans, enterolignans and equol) was compiled using data from available databases, in order to ob...
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