Search results for "fluid"
showing 10 items of 5513 documents
Structures de déformation induites par surpressions de fluide dans les environnements sous-glaciaires et marin profonds : implications paléoenvironne…
2014
Soft-sediment deformation structures (SSDs) occur in unconsolidated sediments, during or shortly after deposition. SSDs are abundant in subglacial and deep-marine environments because of the development of fluid overpressure. Case studies of these two sedimentary environments were used (1) to reconstruct palaeoenvironments from SSDS, and (2) to define the impacts of SSDS on glacial morphologies and (3) petrophysical properties.(1) Analyses of strain regimes, deformation mechanisms, and chronologies in SSDs served to improve palaeoenvironmental reconstructions. These structures were used as proxys to estimate variations of ice flow velocities, ice thickness, meltwater production, and positio…
Toward more realistic viscosity measurements of tyre rubber–bitumen blends
2014
AbstractThe measurement of rheological properties of the tyre rubber bitumen blends is often challenging due to presence of suspended tyre rubber’s crumbs. Furthermore, the phase separation during the course of measurements makes the viscosity of these non-homogeneous blends difficult to ascertain. In this study, a new dual helical impeller was designed and manufactured to be used with a rotational viscometer in order to have a real-time control of the viscosity while performing a laboratory mixing of the blends. Layer based manufacturing techniques showed to be a convenient method to produce complex shaped impeller prototypes before manufacturing the more expensive stainless steel assembly…
Multi-commutation in spectrometry
2009
We review recent developments in manifold components and the introduction of light-emitting-diode technology in spectroscopic detection in order to evaluate the tremendous possibilities offered by multi-commutation for in-field and in-situ measurements, based on the use of multi-pumping and low-voltage, portable batteries, which make possible a dramatic reduction in size, weight and power requirements of spectrometric devices.
Performance Enhancement of Vapour-Compression Refrigeration Systems Using Nanoparticles: An Experimental Study
2021
In recent years, the development and characterization of new refrigerants with higher energetic efficiency have gained considerable interest [1], with a particular emphasis on the energetic performance of suitable replacements. Nanofluids have been proposed as possible alternative due to their role in enhancing the thermophysical proprieties of traditional refrigerants [2]. The comprehensive review in [2] suggests that thermal conductivity of nanofluid increases with temperature and volume concentration, but it is dependent on nanoparticle size distribution; specific heat is also increased if nanoparticles are added to the refrigerant.
Multidisciplinary approach to characterize archaeological materials and status of conservation of the Roman thermae of reggio Calabria Site (Calabria…
2020
This multidisciplinary research focuses on diagnostic investigations to characterize the archaeological materials, as well as the alteration and degradation forms detected at the Roman Thermae of Reggio Calabria (Calabria, South Italy) site. The thermal complex, (dating I–II century B.C.), was built around three main rooms such as the caldarium (hot bath), the tepidarium (warm bath) and the frigidarium (cold bath), all connected to a central room through several entrances. The central hall still preserves a suggestive mosaic floor dating between the II and III century A.D., characterized by geometric motifs and black and white tesserae. Fragments of various archaeological stone materials, s…
34 Early Gene Regulation in Retina and Choroid After Ashpyxia and Resuscitation in Newborn Piglets
2010
34 Early Gene Regulation in Retina and Choroid After Ashpyxia and Resuscitation in Newborn Piglets
Characterization and pilot scale fluidized bed gasification of herbaceous biomass: A case study on alfalfa pellets
2015
Abstract Pilot-scale bubbling fluidized bed gasification tests of alfalfa pellets were performed at two different operational periods ranged on the basis of the two given equivalence ratio (ER) (the ratio between actual air and the stoichiometric air) namely as 0.25 and 0.30. During the test, the solid feeding rate was kept constant at 4.7 kg/h while the air input was varied and thus the ER. Increasing air from 4.16 to 4.99 N m3/h contributed to the evolution pattern of several parameters such as the rise in gas lower heating value (LHV) and gas yield, the average maximum of which were 4.2 MJ/N m3 and 1.5 N m3/kg respectively. Gas composition was mainly boosted by the concentration of CO, a…
New reactive isoeugenol based phosphate flame retardant : toward green epoxy resins
2019
A biobased reactive phosphate flame retardant derived from isoeugenol was synthesized and fully characterized (1H, 13C, 31P NMR, FTIR, MS) with the aim of improving flame retardancy behavior of bio...
A Positive Definite Advection Scheme Obtained by Nonlinear Renormalization of the Advective Fluxes
1989
Abstract A new method is developed to obtain a conservative and positive definite advection scheme that produces only small numerical diffusion. Advective fluxes are computed utilizing the integrated flux form of Tremback et al. These fluxes are normalized and then limited by upper and lower values. The resulting advection equation is numerically solved by means of the usual upstream procedure. The proposed treatment is not restricted to the integrated flux form but may also be applied to other known advection algorithms which are formulated in terms of advective fluxes. Different numerical tests are presented illustrating that the proposed scheme strongly reduces numerical and diffusion an…
Waiting time in quantum repeaters with probabilistic entanglement swapping
2019
The standard approach to realize a quantum repeater relies upon probabilistic but heralded entangled state manipulations and the storage of quantum states while waiting for successful events. In the literature on this class of repeaters, calculating repeater rates has typically depended on approximations assuming sufficiently small probabilities. Here we propose an exact and systematic approach including an algorithm based on Markov chain theory to compute the average waiting time (and hence the transmission rates) of quantum repeaters with arbitrary numbers of links. For up to four repeater segments, we explicitly give the exact rate formulae for arbitrary entanglement swapping probabiliti…