Search results for "fluids"
showing 10 items of 1936 documents
Global Linear Stability Analysis of the Flow Around a Superhydrophobic Circular Cylinder
2016
International audience; Over the last few years, superhydrophobic (SH) surfaces have been receiving an increasing attention in many scientific areas by virtue of their ability to enhance flow slip past solid walls and reduce the skin-friction drag. In the present study, a global linear-stability analysis is employed to investigate the influence of the SH-induced slip velocity on the primary instability of the 2D flow past a circular cylinder. The flow regions playing the role of 'wavemaker' are identified by considering the structural sensitivity of the unstable mode, thus highlighting the effect of slip on the global instability of the considered flow. In addition, a sensitivity analysis t…
Symbolic dynamics in a binary asteroid system
2020
We highlight the existence of a topological horseshoe arising from a a--priori stable model of the binary asteroid dynamics. The inspection is numerical and uses correctly aligned windows, as described in a recent paper by A. Gierzkiewicz and P. Zgliczy\'nski, combined with a recent analysis of an associated secular problem.
Toxic and enzymatic activities of Vibrio vulnificus biotype 2 with respect to host specificity
1996
In this work, the enzymatic activities of selected strains of biotypes 1 and 2 of Vabrio vulnificus were analyzed by using conventional methods and the API ZYM system. The toxic activities of extracellular products (ECPs) were further evaluated by in vitro and in vivo experiments. The ECPs of both biotypes (i) showed high-level hydrolytic activities, (ii) displayed cytotoxicity for fish cell lines, and (iii) were lethal for eels. Exotoxins seem to be proteinaceous since heat treatment of ECP samples destroyed their toxicity. Only biotype 2 strains were virulent for cels, suggesting that host specificity must be related to differences in cell surface properties. Infectivity trials with other…
Lindblad equation approach for the full counting statistics of work and heat in driven quantum systems
2013
We formulate the general approach based on the Lindblad equation to calculate the full counting statistics of work and heat produced by driven quantum systems weakly coupled with a Markovian thermal bath. The approach can be applied to a wide class of dissipative quantum systems driven by an arbitrary force protocol. We show the validity of general fluctuation relations and consider several generic examples. The possibilities of using calorimetric measurements to test the presence of coherence and entanglement in the open quantum systems are discussed. QC 20141010
Effect of pasteurization on the bactericidal capacity of human milk.
2008
The use of human milk in milk banks requires thermal processing to eliminate microbiological hazards. An evaluation is made of the stability of overall human milk bactericidal capacity following 2 modalities of thermal pasteurization: 63°C/30 minutes and 75°C/15 seconds. Ten milk samples (mature milk) were analyzed. In each sample, the effect of both thermal treatments on bactericidal capacity against Escherichia coli was evaluated in relation to the capacity of fresh milk (control). All the samples analyzed possessed bactericidal capacity. Human milk pasteurization induced a significant loss of this capacity that was more pronounced after high-temperature treatment than after low-temperat…
A model for Ischia hydrothermal system: Evidences from the chemistry of thermal groundwaters.
2009
Abstract Ischia volcano, in Central Italy, has long been known for its copious surface hydrothermal manifestations, signs of a pervasive circulation of hot fluids in the subsurface. Because of the significant chemical heterogeneity of fumarolic gas discharges and hot spring discharges, evidences of a complex hydrothermal setting, a definite model of fluid circulation at depth is currently unavailable, in spite of the several previous efforts. Here, we report on the chemical and isotopic composition of 120 groundwater samples, collected during several sampling surveys from 2002 to 2007. The acquired data suggest that the composition of surface manifestations reflect contributions from meteor…
Challenges in truncating the hierarchy of time-dependent reduced density matrices equations
2012
In this work, we analyze the Born, Bogoliubov, Green, Kirkwood, and Yvon (BBGKY) hierarchy of equations for describing the full time evolution of a many-body fermionic system in terms of its reduced density matrices (at all orders). We provide an exhaustive study of the challenges and open problems linked to the truncation of such a hierarchy of equations to make them practically applicable. We restrict our analysis to the coupled evolution of the one- and two-body reduced density matrices, where higher-order correlation effects are embodied into the approximation used to close the equations. We prove that within this approach, the number of electrons and total energy are conserved, regardl…
Benevolent and corrective humor, life satisfaction, and broad humor dimensions : extending the nomological network of the BenCor across 25 countries
2020
Indexación: Scopus. Benevolent and corrective humor are two comic styles that have been related to virtue, morality, and character strengths. A previous study also supported the viability of measuring these two styles with the BenCor in 22 countries. The present study extends the previous one by including further countries (a total of 25 countries in 29 samples with N = 7813), by testing the revised BenCor (BenCor-R), and by adding two criterion measures to assess life satisfaction and four broad humor dimensions (social fun/entertaining humor, mockery, humor ineptness, and cognitive/reflective humor). As expected, the BenCor-R showed mostly promising psychometric properties (internal consi…
Benevolent and corrective humor, life satisfaction, and broad humor dimensions: Extending the nomological network of the BenCor across 25 countries
2019
Benevolent and corrective humor are two comic styles that have been related to virtue, morality, and character strengths. A previous study also supported the viability of measuring these two styles with the BenCor in 22 countries. The present study extends the previous one by including further countries (a total of 25 countries in 29 samples with N = 7813), by testing the revised BenCor (BenCor-R), and by adding two criterion measures to assess life satisfaction and four broad humor dimensions (social fun/entertaining humor, mockery, humor ineptness, and cognitive/reflective humor). As expected, the BenCor-R showed mostly promising psychometric properties (internal consistency and factorial…
Application of gas separation membranes to detritiation systems
2002
The use of gas separation membranes in tritium removal systems has been studied to develop a new detritiation process. The main advantage of this new process is to reduce the number and/or the size of equipments in comparison to conventional detritiation systems. The objective of this study is to choose the best suited membrane for this application. The hydrogen or its isotopes recovery performance of several commercial hollow fiber organic membranes has been analyzed thanks to three devices. Experiments are performed with small quantities of hydrogen gas or deuterium gas or tritium gas in the range representative of the radioactive contamination level in tritium handling gloveboxes. A math…