7,885 research outputs found
Fluid-fluid demixing curves for colloid-polymer mixtures in a random colloidal matrix
We study fluid-fluid phase separation in a colloid-polymer mixture adsorbed
in a colloidal porous matrix close to the \theta -point. For this purpose we
consider the Asakura-Oosawa model in the presence of a quenched matrix of
colloidal hard spheres. We study the dependence of the demixing curve on the
parameters that characterize the quenched matrix, fixing the polymer-to-colloid
size ratio to 0.8. We find that, to a large extent, demixing curves depend only
on a single parameter f, which represents the volume fraction which is
unavailable to the colloids. We perform Monte Carlo simulations for volume
fractions f equal to 40% and 70%, finding that the binodal curves in the
polymer and colloid packing-fraction plane have a small dependence on disorder.
The critical point instead changes significantly: for instance, the colloid
packing fraction at criticality increases with increasing f. Finally, we
observe for some values of the parameters capillary condensation of the
colloids: a bulk colloid-poor phase is in chemical equilibrium with a
colloid-rich phase in the matrix.Comment: 26 pages, 8 figures. In publication in Molecular Physics, special
volume dedicated to Luciano Reatto for his 70th birthda
Consumers' behaviours and attitudes toward healthy food products: The case of organic and functional foods
Over the last decade consumers’ health consciousness is becoming an important factor driving the agrofood market. Healthier food products have entered the global markets with force in the past years and rapidly gained market share. Consequently, the food industry has reacted to this trend by developing a growing variety of new products with health-related claims and images, including organic and functional foods that are selected by consumers for their health-promoting properties. Currently, the healthy foods and drinks market is performing well, in terms of innovation and market penetration; healthy foods in Europe have a turnover of € 5.7 billion. Different researches conclude that a better understanding of consumers' perception of healthy foods and its determinants are key success factors for market orientation and development and for successfully negotiating market opportunities. The research proposes a survey of 300 Italian consumers in order to understand attitudes towards healthy foods, with particular reference to organic and functional products, through the implementation of a cluster analysis. The main aim of this paper is to derive indications that may contribute to better strategic and tactical marketing decisions. The findings of this study are also important for government bodies interested in designing public health programs.functional foods, organic products, cluster analysis, Agricultural and Food Policy, Consumer/Household Economics,
Italian Consumer Attitudes Toward Products for Well-being: The Functional Foods Market
Functional foods, Italian consumers, Market segmentation, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety, Institutional and Behavioral Economics,
Proximity effect with noncentrosymmetric superconductors
We describe the superconducting proximity effect taking place in a contact
between a noncentrosymmetric superconductor and a diffusive
normal/ferromagnetic metal within the quasiclassical theory of
superconductivity. By solving numerically the Usadel equation with boundary
conditions valid for arbitrary interface transparency, we show that the
analysis of the proximity-modified local density of states in the normal side
can be used to obtain information about the exotic superconductivity of
noncentrosymmetric materials. We point out the signatures of triplet pairing,
the coexistence of triplet and singlet pairing, and particular orbital
symmetries of the pair potential. Exploiting the directional dependence of the
spin polarization pair breaking effect on the triplet correlations, we show how
the order relation between triplet and singlet gaps can be discriminated and
that an estimation of the specific gap ratio is possible in some cases.Comment: 11 pages, 4 figure
Simulation of copper-water nanofluid in a microchannel in slip flow regime using the lattice Boltzmann method with heat flux boundary condition
Laminar forced convection heat transfer of water–Cu nanofluids in a microchannel is studied using the double population Thermal Lattice Boltzmann method (TLBM). The entering flow is at a lower temperature compared to the microchannel walls. The middle section of the microchannel is heated with a constant and uniform heat flux, simulated by means of the counter slip thermal energy boundary condition. Simulations are performed for nanoparticle volume fractions equal to 0.00%, 0.02% and 0.04% and slip coefficient equal to 0.001, 0.01 and 0.1. Reynolds number is equal to 1, 10 and 50.The model predictions are found to be in good agreement with earlier studies. Streamlines, isotherms, longitudinal variations of Nusselt number and slip velocity as well as velocity and temperature profiles for different cross sections are presented. The results indicate that LBM can be used to simulate forced convection for the nanofluid micro flows. They show that the microchannel performs better heat transfers at higher values of the Reynolds number. For all values of the Reynolds considered in this study, the average Nusselt number increases slightly as the solid volume fraction increases and the slip coefficient increases. The rate of this increase is more significant at higher values of the Reynolds number
Do Consumers Want More Nutritional and Health Information on Wine Labels? Insights from the EU and USA
The global strategy to reduce the harmful use of alcohol launched in 2010 by the
World Health Organization includes, amongst several areas of recommended actions, providing
consumer information about, and labelling, alcoholic beverages to indicate alcohol-related harm.
Labelling requirements worldwide for alcoholic drinks are currently quite diverse and somewhat
limited compared to labelling on food products and on tobacco. In this context, the current
paper contributes to the academic and political debate on the inclusion of nutritional and health
information on wine labelling, providing some insights into consumer interest in, and preferences
for, such information in four core wine-producing and -consuming countries: Italy, France, Spain,
and the United States of America. A rating-based conjoint analysis was performed in order to
ascertain consumer preferences for different formats of additional information on wine labels, and
a segmentation of the sample was performed to determine the existence of homogeneous groups of
consumers in relation to the degrees of usefulness attached to the nutritional and health information
on wine labels. Our results highlight the interest expressed by European and United States consumers
for introducing nutrition and health information on wine labels. However, the results of conjoint
analysis show some signi\ufb01cant differences among stated preferences of the information delivery
modes in different countries. In addition, segmentation analysis reveal the existence of signi\ufb01cant
differences between consumer groups with respect to their interest in receiving additional information
on wine labels. These differences are not only linked to the geographic origin of the consumers, or
to socio-demographic variables, but are also related to wine consumption habits, attitudes towards
nutritional information, and the degree of involvement with wine. This heterogeneity of consumer
preferences indicates a need for a careful consideration of wine labelling regulations and merits
further investigation in order to identify labelling guidelines in terms of the message content and
presentation method to be used
How log-normal is your country? An analysis of the statistical distribution of the exported volumes of products
We have considered the statistical distributions of the volumes of the
different products exported by 148 countries. We have found that the form of
these distributions is not unique but heavily depends on the level of
development of the nation, as expressed by macroeconomic indicators like GDP,
GDP per capita, total export and a recently introduced measure for countries'
economic complexity called fitness. We have identified three major classes: a)
an incomplete log-normal shape, truncated on the left side, for the less
developed countries, b) a complete log-normal, with a wider range of volumes,
for nations characterized by intermediate economy, and c) a strongly asymmetric
shape for countries with a high degree of development. The ranking curves of
the exported volumes from each country seldom cross each other, showing a clear
hierarchy of export volumes. Finally, the log-normality hypothesis has been
checked for the distributions of all the 148 countries through different tests,
Kolmogorov-Smirnov and Cramer-Von Mises, confirming that it cannot be rejected
only for the countries of intermediate economy.Comment: 10 pages, 5 figures, submitted to IWcee15 conferenc
Spin-sensitive Long-ranged Proximity Effect for Triplet Superconductors
The discovery of noncentrosymmetric superconductors, such as CePtSi, and
chiral superconductors, such as SrRuO, calls for experimental methods
to identify the presence of spin-triplet pairing. We here demonstrate a method
which accomplishes this in an appealingly simple manner: a spin-sensitive
proximity effect in a ferromagnettriplet superconductor bilayer. It is
shown how the orientation of the field can be used to unambiguously distinguish
between different spin-triplet states. Moreover, the proximity effect becomes
long-ranged in spite of the presence of an exchange field and even without any
magnetic inhomogeneities, in contrast to conventional SF junctions. Our
results can be verified by STM-spectroscopy and could be useful as a tool to
characterize the pairing state in unconventional superconducting materials.Comment: 4 pages, 3 figure
- …