Search results for "mass [bottom]"
showing 10 items of 681 documents
Natural Convection Cooling of a Hot Vertical Wall Wet by a Falling Liquid Film
2008
Abstract The system studied is a plane channel in which one of the two vertical walls is kept at an arbitrary temperature profile and may be partially or completely wet by a falling liquid film, while the opposite wall is adiabatic. Air from the environment flows along the channel with a mass flow rate which depends on the balance between hydraulic resistances and buoyancy forces. These latter, in their turn, depend on the distribution of temperature and humidity (hence, density) along the channel and eventually on the heat and mass transferred from wall and film to the humid air. A simplified computational model of the above system was developed and applied to the prediction of relevant qu…
Ethyl Hexanoate Transfer Modeling in Carrageenan Matrices for Determination of Diffusion and Partition Properties.
2007
; Aroma compound properties in food matrices, such as volatility and diffusivity, have to be determined to understand the effect of composition and structure on aroma release and perception. This work illustrates the use of mass transfer modeling to identify diffusion and partition properties of ethyl hexanoate in water and in carrageenan matrices with various degrees of structure. The comparison of results obtained with a diffusive model to those obtained with a convective model highlights the importance of considering the appropriate transfer mechanism. Modeling of the preliminary experimental steps ensures correct estimation of the conditions for the main aroma release step. The obtaine…
New transport properties of ferrocolloids: magnetic Soret effect and thermomagnetoosmosis
2005
The paper deals with critical analysis of experiments on thermodiffusion in ferrocolloids. The observed magnetic Soret effect is significantly stronger than that predicted theoretically. It is shown that the main reason for that is the influence of a magnetic field on mass diffusion. Besides, some measurements are effected by uncontrolled thermal and solutal magnetic convection. Even in porous media, when macroscopic convection is depressed, thermodiffusion can be disturbed by microconvective mass transfer induced by particle magnetophoresis on filter grains.
Heat and mass transfer phenomena in magnetic fluids
2007
In this article the influence of a magnetic field on heat and mass transport phenomena in magnetic fluids (ferrofluids) will be discussed. The first section is dealing with a magnetically driven convection, the so called thermomagnetic convection while in the second section the influence of a temperature gradient on the mass transport, the Soret effect in ferrofluids, is reviewed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of turbulent metal flows
2007
Comprehensive knowledge of the heat and mass transfer processes in turbulent metal flows is required to realize efficient and reliable melting and casting processes. Experimental and numerical studies of the melt flow in induction furnaces show that the flow pattern, which comprise several vortexes of the mean flow, and the temperature distribution in the melt are significantly influenced by low-frequency large scale flow oscillations. Two- and three-dimensional hydrodynamic calculations of the melt flow, using two-equation turbulence models based on Reynolds Averaged Navier-Stokes approach, do not predict the large scale periodic flow instabilities obtained from the experimental data. That…
Transfer of Water and Volatiles at Interfaces: Application to Complex Food Systems
2013
International audience; During processing, storage and consumption, mass transfer of various small molecules (water, gases, flavour compounds or other solutes) occurs between the different phases in complex food products, or between complex food and its surroundings. These mass transfers can lead to physical or chemical changes and thus induce food quality modifications.The objective of this paper is to better understand the behaviour of small molecules at the interfaces, especially in model heterogeneous food systems. Different techniques have been designed to characterize mass transfers of these small molecules and their effects on food properties. In particular, techniques such as rotati…
Football Without Football: Creativity in German Football Coverage by TV Broadcasters and Clubs During the Coronavirus Crisis
2020
During the COVID-19 pandemic, TV broadcasters and clubs were challenged to provide alternative formats and content for fans of Germany’s favorite sport, football [soccer]. Thus, they emulated matchdays and created a Bundesliga feeling in new ways. The authors focus on this alternative creative sports coverage during the Coronavirus crisis and consider the effect on the audience. TV broadcasters, for instance, recreated Bundesliga matchdays through broadcasting historical matches, sticking with the original fixtures from before the crisis, while offering renewed commentary. Clubs conducted the Bundesliga Home Challenge, that is, FIFA20 videogame matches with their professional and eSport pla…
The transient gravitational-wave sky
2013
Interferometric detectors will very soon give us an unprecedented view of the gravitational-wave sky, and in particular of the explosive and transient Universe. Now is the time to challenge our theoretical understanding of short-duration gravitational-wave signatures from cataclysmic events, their connection to more traditional electromagnetic and particle astrophysics, and the data analysis techniques that will make the observations a reality. This paper summarizes the state of the art, future science opportunities, and current challenges in understanding gravitational-wave transients.
Which is the best communication strategy, based on anti-tobacco ads, to impress teenagers? A multicenter cross-sectional study
2020
Background. Well-planned mass-media campaigns can increase health literacy and raise awareness about the consequences of tobacco use. This study aims to evaluate the emotions and opinions of adolescents about several anti-tobacco spots delivered by the mass media over the world. Study design. Cross-sectional study. Methods. The study was conducted in Italy in 2016–2017 among students aged 13–17 years. Students expressed their emotions and opinions about seven anti-tobacco spots from all over the world on different topics and styles. Results. 499 students attended. The video “Sponge” was found to be the most impressive (30.2%) and what they would have chosen if they had been responsible for …
Sobre la interiorización del espacio social
2009
The author explores the relationships between the exterior world and the inner world in the diverse types of messages and reproducing products of the mass media, analyzing the cultural roots, the ideological, political, and social features that these relationships show. The different reproducing cultural forms create passages and virtual spaces which mediates the space to link it with the inner life. Above all, the author finds that the meditating and informative processing of the public space has a direct link with the modern capitalism in its expansive and privatizing tendency, and it is essential to study today into depth the processes which connect the expansion pf cultural and informat…