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11.
Marina Contini Simone Baccelloni Maria Teresa Frangipane Nicolò Merendino Riccardo Massantini 《Journal of Functional Foods》2012,4(1):137-146
The simultaneous consumption of different classes of phytochemical antioxidants in the diet can result in more beneficial effects than when consumed alone. In the present study, the in vitro and in vivo antioxidative effects of espresso coffee brew (EC) (rich in chlorogenic acids) with added crude hazelnut skin phenolic extract (HSPE) from hazelnut skin waste (rich in flavonoids) were studied. Both post-brewing and pre-brewing phenolic-enriched espresso coffees (PE-ECs) were analysed for total phenols and screened for their in vitro antiradical ability. Moreover, the in vivo biological effect on the antioxidant potential of plasma in rats was evaluated. The PE-ECs showed increased both in vitro and in vivo antiradical activity proportional to the added HSPE. The in vivo experiments suggested that HSPE was much more antioxidant active than the phenolic fraction naturally contained in EC. Moreover, evidence of possible synergic effects of EC and HSPE phenolics was observed in vivo. 相似文献
12.
Effect of different treatments on the microstructure and functional and pasting properties of pigeon pea (Cajanus cajan L.), dolichos bean (Dolichos lablab L.) and jack bean (Canavalia ensiformis) flours from the north‐east Argentina 下载免费PDF全文
Belén A. Acevedo Cinthia M. B. Thompson Nicolás S. González Foutel María G. Chaves María V. Avanza 《International Journal of Food Science & Technology》2017,52(1):222-230
The effect of germination (G; 5 days), soaking‐cooking (SC; 6 h–20 min, 6 h–40 min, 6 h–60 min) and microwave (M; 50%, 70%, 100%) treatments on pigeon pea (PP), dolichos bean (DB) and jack bean (JB) seeds was studied. Microstructure of seeds and functional (protein solubility, water‐holding capacity, oil‐holding capacity, emulsion stability) and pasting properties of flours were determined. Germination and microwave treatments modified the protein matrix of cotyledon cells preserving the shape of the starch granule, whereas the SC treatment (6 h–60 min) affected both. The soaking‐cooking is the most influential treatment on the functional properties of PP, DB and JB flours, as increased water absorption capacity (73–96%), decreased protein solubility (>80%) and the tendency to retrogradation of amylose (69–85%) also improved emulsion stability. 相似文献
13.
Helio Fiori de Castro Katia Lucchesi Cavalca Lucas Ward Franco de Camargo Nicoló Bachschmid 《Mechanical Systems and Signal Processing》2010,24(6):1785-1798
This paper discusses the identification of parameters in rotary systems, namely, the unbalance magnitude, phase and position in the rotor system. These parameters can be identified using the measured orbits in the hydrodynamic bearings. The oil film forces are evaluated in the different positions of the orbit of the journal and are applied to the model of the shaft. The model, integrated in time domain, allows with an assumed unbalance, to simulate the orbits. The objective function is basically the difference between measured and simulated orbits, and its minimum corresponds to the identified unbalance amount, phase and position along the shaft. With respect to traditional model based identification procedures, this approach using oil film forces instead of oil film linearized stiffness and damping coefficients, and unfiltered orbits instead of 1X vibration components is suitable to deal with non-linear behaviour of the system. 相似文献
14.
Nicolás Tenaglia Roberto Boeri Graciela Rivera Juan Massone 《International Journal of Cast Metals Research》2016,29(1-2):112-120
This study aims at identifying the relationship between the shrinkage cavities and the solidification structure in spheroidal graphite cast iron. Cast samples specially designed to contain shrinkage cavities were used. The solidification macrostructure was revealed using the Direct Austempering After Solidification method, while the solidification microstructure was revealed by using colour etching. At the midsection of the pieces, the shrinkage cavities and the solidification structure were observed jointly. The study showed that the classification of shrinkage porosity found in literature does not correspond to the ductile iron solidification model recognized by most of the scientific community. Early solidification models, and therefore shrinkage formation mechanisms, were proposed in instances when there was not a thorough knowledge of the morphology of the solid phases during solidification. Nowadays, defects formation mechanisms can be described with higher accuracy. Therefore, an updated classification of shrinkage porosity for spheroidal graphite iron is proposed. 相似文献
15.
Metallurgical and Materials Transactions B - To provide fundamental information on the phases and microstructures formed during sintering, a liquid with a bulk composition within the silico ferrite... 相似文献
16.
A national quantitative survey of Salmonella in five types of uncooked retail meats in New Zealand was undertaken from August 2003 to May 2005 to establish baseline proportionality data. The overall prevalence of Salmonella in 1,108 meat samples was 1.1% (95% confidence interval, 0.6 to 1.9). Low prevalences of Salmonella in each meat type were observed, with 3% (1.2 to 6.1) in chicken, 1.3% (0.3 to 3.8) in lamb and mutton, 0.5% (0 to 3.0) in unweaned veal, 0.4% (0 to 2.4) in beef, and 0% (0 to 1.6) in pork. The Salmonella serotypes isolated were Salmonella Infantis from beef; Salmonella Typhimurium PT1 from unweaned veal and chicken; Salmonella sp. 6,7:k:-, Salmonella Enteritidis PT9a, Salmonella sp. 4,5,12:-:-, Salmonella sp. 4,12:-:-, and Salmonella Typhimurium PT160 from chicken; and Salmonella sp. 4:-:2 and Salmonella Brandenburg from lamb. Four of the isolates from chicken, Salmonella sp. 4,5,12:-:- (two isolates), Salmonella sp. 4,12:-:-, and Salmonella Typhimurium PT1, were very similar phenotypically and serologically to the attenuated Salmonella vaccine strain used in MeganVacl for poultry. One lamb sample yielded a count of Salmonella Brandenburg of 4.24 most probable number (MPN)/g, while all other positive samples were <1.0 MPN/g. The results provide baseline proportionality data for Salmonella in retail uncooked meats that will contribute invaluably toward future risk assessment in light of other information, such as consumption data that can be used for risk characterization. 相似文献
17.
18.
Antimicrobial and antibiofilm activities of procyanidins extracted from laurel wood against a selection of foodborne microorganisms 下载免费PDF全文
Alfonso Alejo‐Armijo Nicolás Glibota María P. Frías Joaquín Altarejos Antonio Gálvez Elena Ortega‐Morente Sofía Salido 《International Journal of Food Science & Technology》2017,52(3):679-686
This study aimed to evaluate the antimicrobial and antibiofilm activities of two procyanidins isolated from an ethyl acetate extract of laurel wood against a selection of foodborne pathogens. The analysis of the extract by HPLC–DAD/ESI–MS allowed us to detect the presence of two procyanidins, which were selectively isolated and identified by chromatographic and spectroscopic means as cinnamtannin B‐1 ( 1 ) and procyanidin B‐2 ( 2 ). Procyanidins 1 and 2 exhibited two biological activities: inhibition of bacterial growth at high concentrations and prevention of biofilm formation at lower concentrations. Synergistic effect was also detected when both compounds were tested in combination against Listeria monocytogenes. Significant effects were also detected on disruption of preformed biofilm. The ability of procyanidins to inhibit microbial growth and biofilm formation and to synergistically work with each other may stimulate a market as natural food preservatives, and/or natural sanitisers for processing equipment where foodborne pathogens reside. 相似文献
19.
Commercially available chelating resins with the iminodiacetate functional group have been evaluated for their suitability for the adsorption of nickel and other metal ions by a resin-in-pulp process from the tailings of a pressure acid leach process for nickel laterites. The Amberlite IRC 748 and TP 207 MonoPlus resins were found to be the most suitable in terms of loading capacity for nickel and kinetics of adsorption. The resin with the highest nominal capacity was observed to adsorb less nickel as a result of the adsorption of greater amounts of the impurity ions. The equilibrium loading for nickel on the preferred resin was found to be similar from the ammonium and protonated form of the resin although the kinetics of adsorption is greater when the resin is initially in the ammonium form. A study of the kinetics of the loading of nickel and cobalt from pulp has shown that the rate can be described in terms of a first-order approach to equilibrium. The optimum pH for adsorption was found to be in the range 4 to 5 as this pH is high enough to maximize the adsorption of nickel and cobalt while preventing precipitation of nickel and cobalt as hydroxides from the pulp. A method for minimizing the competition from more strongly loaded ions such as iron(III) and chromium(III) which are present in the pulp was also developed in the initial laboratory phase of the study. 相似文献
20.
Michele Dei Nicolò Nizza Massimo Piotto Paolo Bruschi 《Analog Integrated Circuits and Signal Processing》2009,58(1):43-47
A compact voltage controlled CMOS current divider is presented. Differently from previous implementations, exploiting the
MOSFET translinear characteristics in subthreshold region, the proposed circuit is based on devices operating from moderate
to strong inversion. An input current linearity range of nearly a decade is obtained by compensating for the deviations from
the ideal drain current square-law approximation through an original empirical approach. The circuit is suitable for use as
a building block in analog multipliers and for transconductor continuous tuning. The effectiveness of the proposed configuration
is demonstrated by means of electrical simulations, performed on a prototype designed with a commercial process. The robustness
of the linearization algorithm with respect to temperature variations is proven. 相似文献