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131.
Luna Greco Rossella RiccioSabina Bergero Attilio A.M. Del ReMarco Trevisan 《Food chemistry》2007,103(4):1127-1133
Processing and preparation methods are generally believed to result in a depletion of naturally occurring antioxidants in food. To evaluate the antioxidant properties of fresh sweet peppers (Capsicum annuum) and five different Italian recipes based on sweet peppers (pickled; “peperonata”; grilled; in sour–sweet condiment; salted), water- and lipid-soluble extracts from fresh and processed peppers were analysed using high-performance liquid chromatography coupled with an electrochemical detector. Total reducing capacity (TRC) and contributions of hydrophilic reducing capacity (HRC) and lipophilic reducing capacity (LRC) to the TRC were determined in all the samples. Three important antioxidant compounds were measured: ascorbic acid, β-carotene and lycopene. The contribution of these individual compounds to TRC was estimated. 相似文献
132.
133.
AbstractThis paper deals with Kriging models applied to optimise braking performances for freight trains. More precisely, it is focused on mass distribution optimisation aimed at reducing the effects of in-train forces among vehicles, e.g. compression and tensile forces, in-train emergency braking. To this end, Kriging models are applied with covariance structure based on the Matérn function, introducing specific input parameters to better outline the payload distribution on the train, also evaluating the shape of the payload distribution. The different shapes, related to the payload distributions, have been implemented into a model through a Python routine, which has been used to ‘assemble’ the simulated trains. The analysed train carries 80% of its maximum payload capacity during an emergency braking from the speed of 30 km/h. Satisfactory results have been obtained considering compression forces, tensile forces and their sum, also considering residuals and diagnositc measures. 相似文献
134.
The room temperature oxidation of vapor-deposited titanium films was investigated as a function of film thickness by resistivity and ellipsometric measurements. The thickness of the films ranged from 3.0 to 120 nm. The electron mean free path in the films varied from 11.3 to 26.0 nm, and the product of the bulk resistivity and the electron mean free path was 1.5 × 10-10Ω cm2. The values of the surface electron scattering parameter in the films were between 0.2 and 0.6 and decreased to 0.18 at the onset of oxidation. The best value for the complex refractive index of titanium was found to be 3.61-i4.06. The refractive index of the oxide film was 2.75. After a 1 d exposure of the films to room air at atmospheric pressure both the resistance and ellipsometric measurements indicated a residual oxide thickness of 2.6±0.3 nm, regardless of the original metal film thickness. These results disagree with the theoretical and experimental results of Mindel and Pollack, which implied a rapid decrease in oxide thickness with decreasing titanium film thickness. 相似文献
135.
Settanni L Di Grigoli A Tornambé G Bellina V Francesca N Moschetti G Bonanno A 《International journal of food microbiology》2012,155(1-2):73-81
The present work was undertaken to evaluate the influence of the wooden dairy plant equipment on the microbiological characteristics of curd to be transformed into Caciocavallo Palermitano cheese. Traditional raw milk productions were performed concomitantly with standard cheese making trials carried out in stainless steel vat inoculated with a commercial starter. Milk from two different farms (A and B) was separately processed. The wooden vat was found to be a reservoir of lactic acid bacteria (LAB), while unwanted (spoilage and/or pathogenic) microorganisms were not hosted or were present at very low levels. All microbial groups were numerically different in bulk milks, showing higher levels for the farm B. LAB, especially thermophilic cocci, dominated the whole cheese making process of all productions. Undesired microorganisms decreased in number or disappeared during transformation, particularly after curd stretching. LAB were isolated from the wooden vat surface and from all dairy samples, subjected to phenotypic and genetic characterization and identification. Streptococcus thermophilus was the species found at the highest concentration in all samples analyzed and it also dominated the microbial community of the wooden vat. Fourteen other LAB species belonging to six genera (Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Streptococcus and Weissella) were also detected. All S. thermophilus isolates were genetically differentiated and a consortium of four strains persisted during the whole traditional production process. As confirmed by pH and the total acidity after the acidification step, indigenous S. thermophilus strains acted as a mixed starter culture. 相似文献
136.
137.
A 3-D computer code for the calculation of magnetic fields, self- and mutual-inductance coefficients, and electromagnetic forces is considered. A unique feature of this code is the presence of a number of very precise models for the calculation of the field produced by circular or noncircular coils, busbars, or any other kind of conductor of arbitrary shape. The possibility of using different coordinate systems for input/output data represents an additional user-oriented facility. The problems of singularities both for the elliptic integral calculation, used for circular coils, and for Biot-Savart's integral have been taken into account for the field calculation inside the conductors. Since this code has been conceived to solve magnetostatic problems in air-core devices for fusion research, an easy input for particular windings, such as toroidal and poloidal windings, is also provided. A means for automatic generation of the points of the current lines in busbars and in noncircular coils has been inserted in the code as well 相似文献
138.
Pistocchi R Cangini M Totti C Urbani R Guerrini F Romagnoli T Sist P Palamidesi S Boni L Pompei M 《The Science of the total environment》2005,353(1-3):307-316
Oceanographic cruises were carried out monthly from June 1999 to July 2002 to follow the mucilage formation process in the Northern Adriatic Sea. Results show that in correspondence with these events the dinoflagellate Gonyaulax fragilis (Schütt) Kofoid was observed both in the water column and within mucilage aggregates. In the water column, increasing abundances were observed from May until July, with values never exceeding 8500 cells l(-1). Much higher densities were observed within superficial gelatinous aggregates (22800-3400000 cells l(-1)). In mucilage samples, a large number of decomposing cells were present, together with abundant alive cells, enveloped in exudates. G. fragilis isolated from mucilage samples was cultured in three different culture media; it was characterized by a low growth rate but it produced a high amount of polysaccharides. The highest yield both in terms of cell number and carbohydrate production was observed in the medium having the highest nitrogen and phosphorus content and the lowest N/P ratio. The monomeric composition of G. fragilis carbohydrates, compared with that of mucilage samples, showed that in both natural and cultured samples galactose was the most abundant sugar; in addition, an overall good correlation, especially between the monomeric carbohydrate composition of G. fragilis grown in f/2 medium and that of a mucilage sample in which this species was present in high density, was observed. 相似文献
139.
Chickens can easily be induced to develop delayed-type skin reactions to oxazolone when animals are sensitized 7 days before the challenge. The reaction is quantitated by assessing the increase in wattle thickness: maximum reactions occur 24 h after challenge. The reaction is inhibited by neonatal thymectomy or bursectomy; these findings therefore suggest also an important B-derived component in delayed hypersensitivity to oxazolone. 相似文献
140.
Giacomo?Cabri Luca?Ferrari Rossella?RubinoEmail author 《Artificial Intelligence and Law》2008,16(1):129-145
While the sociality of software agents drives toward the definition of institutions for multi agent systems, their autonomy
requires that such institutions are ruled by appropriate norm mechanisms. Computational institutions represent useful abstractions.
In this paper we show how computational institutions can be built on top of the RoleX infrastructure, a role-based system
with interesting features for our aim. We achieve a twofold goal: on the one hand, we give concreteness to the institution
abstractions; on the other hand, we demonstrate the flexibility of the RoleX infrastructure. 相似文献