Search results for "mixture"
showing 10 items of 1178 documents
On the bubbling dynamics of binary mixtures of powders in 2D gas-solid fluidized beds
2012
Abstract The bubbling behavior of fluidized beds has been thoroughly investigated in the last decades by means of several techniques (e.g. X-ray, Inductance, Resistance and Impedance based techniques). In recent years, Digital Image Analysis Techniques have shown their potential for accurate and cost effective measurements. Most of the works related to the experimental analysis of bubble behavior in the field of gas-solid fluidization actually deal with monodispersed particles although almost all industrial equipments operate with mixtures of particles. Among the works available in literature dealing with mixtures of particles having different diameters and/or densities, most of them aim at…
Effect of the surrounding aeration on microcapillary electrochemical cell experiments
2008
In the microelectrochemical capillary cell technique a silicone rubber gasket is used to avoid any electrolyte leakage between the pulled glass capillary and the working electrode (the metallic tested material). In this study, it is demonstrated that the oxygen reduction reaction (ORR) is strongly affected by the use of the silicone rubber. Experiments under a surrounding argon gas shielding of the pulled capillary in contact with the metallic surface have been performed showing a large effect on the ORR. Considering the high permeation rate of oxygen through silicone, the decrease of the reaction rate observed experimentally was validated by FEM modelling assuming that the air/silicone/wat…
Importance of dispersal and thermal environment for mycorrhizal communities: lessons from Yellowstone National Park
2011
International audience; The relative importance of dispersal and niche restrictions remains a controversial topic in community ecology, especially for microorganisms that are often assumed to be ubiquitous. We investigated the impact of these factors for the community assembly of the root-symbiont arbuscular mycorrhizal fungi (AMF) by sampling roots from geothermal and nonthermal grasslands in Yellowstone National Park (YNP), followed by sequencing and RFLP of AMF ribosomal DNA. With the exception of an apparent generalist RFLP type closely related to Glomus intraradices, a distance-based redundancy analysis indicated that the AMF community composition correlated with soil pH or pH-driven c…
"Table 2" of "Measurement of differential Z / gamma* + jet + X cross sections in p anti-p collisions at s**(1/2) = 1.96-TeV"
2008
Measured cross section as a function of the jet rapidity.
Perceptual odor blending is influenced by chemical complexity of odorant mixtures
2008
International audience; Perfumers and flavorists are familiar with odor blending phenomenon and often report that a minimum number of odorants has to be mixed for a good odor blend to arise. Previous studies in humans and animals suggested that a configural process could be involved in the perceptual analysis of mixtures of odorants. It has been proposed that the perceptual blending phenomenon corresponds to a configural perception of odorant mixtures. In the present study, we investigated the influence of chemical complexity on the configural perception of odorant mixtures. Six mixtures including 2 to 6 odorants as well as each unmixed odorant were assessed for their odor quality by a pane…
Influence of the stereochemistry and of the functionality of organic molecules on the hydration of cementitious compounds
2015
The current limited knowledge on the interactions between organic admixtures and mineral phases as well as their influence on the hydration mechanisms of the Ordinary Portland Cement (OPC) represents a real limitation in the development of new organic products with improved and controlled properties. Here, this study intended to understand why and how organic admixtures modify the setting time of OPC by progressively varying the characteristics of simple organic molecules such as their charge, functional groups (hydroxyl, hydroxy-carboxylate, carboxylate, sulfonate and phosphonate) and the stereochemistry of their hydroxyl groups.The different retardations induced by the organic molecules s…
On-Line Measurement of Gaseous Iodine Species During a PWR Severe Accident
2015
International audience; Iodine is a highly radio-toxic element, due to its affinity to the thyroid, and represents the major part of the radioactivity released during a nuclear accident. In the context of nuclear safety and radio-protection, we are interested in identifying the iodine gaseous species which are released, in the nuclear power plants, under molecular (I$_2$) and organic (CH$_3$I) forms. Therefore, we are working on providing a spectroscopic database for both species. While the infrared spectrum of the ν6 band of methyl iodide was previously studied, only 4000 lines were assigned. We present the rovibrational analysis of a high quality experimental spectrum, of this band, recor…
Impact of proportion on configural perception of odor mixtures in a newborn mammal
2009
International audience; Configural perception of odor mixtures appears functional early in life. Recent results underline that after the learning of a binary mixture. (AB) that blends in humans, newborn rabbits respond both to the mixture and to its components. However, after the learning of. a single component they do not generalize to the mixture. This suggests that they perceive more in the mixture than the odor of each. constituent (Coureaud et al., Physiol. Behav. 2008). Here, we pursued the assessment of their configural perception of AB, with the. aim to determine whether specific component proportions of A and B elicit the perceptual emergence of an additional odor in AB. Starting. …
Impact of distribution heterogeneity of microorganisms and 2,4-D on biodegradation processes in soil : experiment and modelling
2013
Impact of distribution heterogeneity of microorganisms and 2,4-D on biodegradation processes in soil : experiment and modelling. Conference on Pesticide Behaviour in Soils, Water and Air (York 2013)
Effect of cropping cycles and repeated herbicide applications on the degradation of diclofop-methyl, bentazone, diuron, isoproturon and pendimethalin…
2002
A greenhouse study was conducted to investigate the ability of four crops (wheat, corn, oilseed rape and soybean) to influence the degradation of bentazone, diclofop-methyl, diuron, isoproturon and pendimethalin in soil. The present study showed that microbial biomass-carbon was significantly higher in planted soils than in bulk soil, especially with wheat and corn, after several cropping cycles. The biomass in corn and soybean planted soils was adversely affected by bentazone but recovered after three cropping cycles. In wheat-planted soils, diclofop-methyl application resulted in persistent increase of the amount of microbial biomass. Bentazone did not show accelerated degradation even af…