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991.
Antonella Bosso Silvia Motta Loretta Panero Stefania Lucini Massimo Guaita 《Journal of food science》2020,85(8):2406-2415
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Ana Teresa Serra J. Rocha B. Sepodes Ana A. Matias Rodrigo P. Feliciano Agostinho de Carvalho Maria R. Bronze Catarina M.M. Duarte M.E. Figueira 《Food chemistry》2012
Epidemiological evidence supports the concept that diets rich in fruits and vegetables promote health and attenuate or delay the onset of cardiovascular disease (CVD). In particular, a reduced risk of CVD has been associated with apple consumption, probably due to the cholesterol-lowering effect of the main bioactive compounds, namely fibre and polyphenols. 相似文献
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Laminar natural convection inside air-filled, rectangular enclosures heated from below and cooled from above, with the lower portions of both sidewalls maintained at the temperature of the bottom wall, and the remaining upper portions of the sidewalls maintained at the temperature of the top wall, is studied numerically. A control volume formulation of the finite-difference method is used for the solution of the mass, momentum, and energy transfer governing equations. Simulations are performed for height-to-width aspect ratios of the cavity from 1 to 5, Rayleigh numbers based on the height of the cavity from 5 × 102 to 5 × 106, and values of the heated fractions of both sidewalls from 0 to 1. It is found that when the heated portions of the two sidewalls are different in length, a steady-state solution is reached, with a basic three-cell flow pattern. In contrast, when the heated fractions of the sidewalls are the same, the asymptotic solution may be either stationary, with a flow field consisting of two pairs of superimposed roll cells, or periodic, with a flow pattern consisting of a primary cell and two secondary cells that pulsate about the center of the enclosure. Dimensionless heat transfer correlating equations are proposed. 相似文献
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Thermal large eddy simulations are carried out in order to study the convective flow in a solar receiver. We investigate the impact of thermal gradients on a turbulent channel flow with imposed wall temperatures for two turbulent Reynolds numbers based on the friction velocity (180 and 395). In this configuration, the flow is subsonic, while temperature variations can be strong and induce significant variations of the fluid properties. The low Mach number equations are considered. The influence of the variations of the conductivity and the viscosity is first investigated. We show that the influence of these properties can be considered constant only for weak temperature gradients. The thermal subgrid-scale modeling is studied and we conclude that for a temperature ratio of 2, we can use a constant subgrid-scale Prandtl number. Finally, we focus on the increase of the temperature ratio that emphasizes the flow dissymmetry and modifies the fluctuations profiles. The physical mechanism responsible for these modifications is explained. 相似文献
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This article shows an intelligent work assistant device that has been developed within the European Project called CyberManS. This device can be used in the car industry for welding automotive components to achieve the required flexibility without overloading the human worker. © 2010 Wiley Periodicals, Inc. 相似文献
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