Search results for "Mixing"
showing 10 items of 795 documents
Characterization of micromixing in a Continuous Oscillatory Baffled Reactor
2018
International audience; Micromixing is the limiting step in the progress of fast reactions and fast crystallization processes. Micromixing performance of a Nitech© glass COBR has been characterized using the competing parallel iodide-iodate test reactions. Macromixing length was also qualitatively determined by visualization of a tracer. The results show that an increase in the amplitude to baffle space ratio and a decrease of oscillation frequency improves mixing performance.
B-K-parameter from N-f=2 twisted mass lattice QCD
2011
We present an unquenched N-f = 2 lattice computation of the B-K parameter which controls K-0 - (K) over bar (0) oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence quarks of both the maximally twisted and the Osterwalder-Seiler variety. Suitable combinations of these two kinds of valence quarks lead to a lattice definition of the B-K parameter which is both multiplicatively renormalizable and O(a) improved. Employing the nonperturbative RI-MOM scheme, in the continuum limit and at the physical value of the pion mass we get B-K(RGI) = 0.729 +/- 0.030, a number well in line with the existing quenched and unquenched d…
Suitability of Phytosterols Alongside Fatty Acids as Chemotaxonomic Biomarkers for Phytoplankton
2016
The composition and abundance of phytoplankton is an important factor defining ecological status of marine and freshwater ecosystems. Chemotaxonomic markers (e.g., pigments and fatty acids) are needed for monitoring changes in a phytoplankton community and to know the nutritional quality of seston for herbivorous zooplankton. Here we investigated the suitability of sterols along with fatty acids as chemotaxonomic markers using multivariate statistics, by analyzing the sterol and fatty acid composition of 10 different phytoplankton classes including altogether 37 strains isolated from freshwater lakes. We were able to detect a total of 47 fatty acids and 29 sterols in our phytoplankton sampl…
Fabric evolution and the related swelling behaviour of a sand/bentonite mixture upon hydro-chemo-mechanical loadings
2015
This experimental study investigates the swelling behaviour of an 80/20 sand/bentonite mixture and the associated fabric evolution under different hydro-chemo-mechanical loadings. Free and confined swelling tests are performed on specimens compacted to different dry densities and wetted with different pore fluids. Controlled suction confined swelling tests are performed to determine the suction–swelling pressure relationship for two different densities. An extensive microstructural characterisation is performed to relate the observed swelling behaviour to the evolution of the different pore networks during wetting. Based on the microstructural analysis, an expression is proposed to determi…
Distillation and stripping pilot plants for the JUNO neutrino detector: Design, operations and reliability
2019
Abstract This paper describes the design, construction principles and operations of the distillation and stripping pilot plants tested at the Daya Bay Neutrino Laboratory, with the perspective to adapt these processes, system cleanliness and leak-tightness standards to the final full scale plants to be used for the purification of the liquid scintillator of the JUNO neutrino detector. The main goal of these plants is to remove radio impurities from the liquid scintillator while increasing its optical attenuation length. Purification of liquid scintillator will be performed with a system combining alumina oxide, distillation, water extraction and steam (or N 2 gas) stripping. Such a combined…
Triple resonant four-wave mixing: A microwatt continuous-wave laser source in the vacuum ultraviolet region at 120 nm
2012
We present a vacuum ultraviolet laser source by four-wave mixing in mercury vapour based on solid-state laser systems. Maximum powers of 6μW were achieved with an increase of four orders of magnitude in efficiency.
Current Problems in the Modelling of Photochemical Reactors
1985
Photochemical reactors are examined from the point of view of the main problems connected to their modelling. By distinguishing the diverse meanings of kinetic models and the varied objectives in establishing models, a particular attention is devoted to the following aspects of homogeneous photoreactors: steady state condition, effect of stirring and mixing, effect of the shape of the reactor and of the position of the light source, light emission models, scale up. For the heterogeneous systems only general considerations on kinetic models in heterogeneous photocatalysis and on the problems related to the use of fluidized bed photoreactors are done.
Linear dynamics induced by odometers
2022
Weighted shifts are an important concrete class of operators in linear dynamics. In particular, they are an essential tool in distinguishing variety dynamical properties. Recently, a systematic study of dynamical properties of composition operators on $L^p$ spaces has been initiated. This class of operators includes weighted shifts and also allows flexibility in construction of other concrete examples. In this article, we study one such concrete class of operators, namely composition operators induced by measures on odometers. In particular, we study measures on odometers which induce mixing and transitive linear operators on $L^p$ spaces.
Dictionaries and translation of contemporary novels
2014
Par leur caractère polyphonique, de nombreux romans contemporains posent des problèmes lexicaux au traducteur en mélangeant lexique standard, argot et termes techniques. La question qui se pose est alors de savoir si les dictionnaires peuvent être utiles au praticien. Nous verrons que pour des raisons théoriques et pratiques, l’aide qu’ils apportent est limitée, un dictionnaire réellement utile devrait changer ses présupposés conceptuels, donc devenir un dictionnaire culturel et adopter une forme électronique. Lexical problems do arise in many contemporary novels because of their polyphonic nature, mixing standard words, slang and technical terms. We must then ask ourselves if dictionaries …
A Hybrid Agent Model, Mixing Short Term and Long Term Memory Abilities
1999
We present in this paper a novel approach for the modeling of agents able to react and reason under highly dynamic environments. A hybrid agent architecture is described, which allows to integrate the capacity to react rapidly to instantaneous changes in the environment with the capacity to reason more thoroughly about perceptions and actions. These capacities are implemented as independent processes running concurrently, and exploiting different memorizing abilities. Only a short-term memory is made available to reactive agents, whilst long-term memorizing abilities together with the possibility to reason about incomplete information is provided to cognitive agents. This model is currently…