Search results for "Fluids"

Population trapping due to cavity losses

2008

In population trapping the occupation of a decaying quantum level keeps a constant non-zero value. We show that an atom-cavity system interacting with an environment characterized by a non-flat spectrum, in the non-Markovian limit, exhibits such a behavior, effectively realizing the preservation of nonclassical states against dissipation. Our results allow to understand the role of cavity losses in hybrid solid state systems and pave the way to the proper description of leakage in the recently developed cavity quantum electrodynamic systems.

Entanglement trapping in structured environments

2008

The entanglement dynamics of two independent qubits each embedded in a structured environment under conditions of inhibition of spontaneous emission is analyzed, showing entanglement trapping. We demonstrate that entanglement trapping can be used efficiently to prevent entanglement sudden death. For the case of realistic photonic band-gap materials, we show that high values of entanglement trapping can be achieved. This result is of both fundamental and applicative interest since it provides a physical situation where the entanglement can be preserved and manipulated, e.g. by Stark-shifting the qubit transition frequency outside and inside the gap.

Two-qubit entanglement generation through non-Hermitian Hamiltonians induced by repeated measurements on an ancilla

2020

In contrast to classical systems, actual implementation of non-Hermitian Hamiltonian dynamics for quantum systems is a challenge because the processes of energy gain and dissipation are based on the underlying Hermitian system&ndash

Procesos hidrotermales con enriquecimiento en REE en las carbonatitas de Fuerteventura: evidencias en minerales accesorios

2021

Carbonatitic dykes that crop out in the central western part of Fuerteventura Basal Complex (Ajuy, Punta de la Nao), were affected by the Miocene intrusive event responsible for contact metamorphism and partial melting of part of the alkaline-carbonatitic complex. Textural characteristics, monazite enriched in LREE (La, Ce, Nd) formation processes in microfractures that affect zircon crystals, show carbonatite interactions with hydrothermal fluids and partial REE remobilization. Pyrochlore is the main mineral carrier of rare earth elements (sum REE=216694 ppm), with high LREE (LaN=185816 and CeN=165209) with respect to HREE (YbN=2589 and LuN=1814) with a rather steep pattern (La/Yb)N=72 in …

STUDIO DI UNA FRIZIONE MAGNETOREOLOGICA PER AUTOVEICOLI

2013

Dopo un’accurata ricerca bibliografica sui fluidi magnetoreologici, il loro comportamento ed impiego, si è passati alla progettazione di una frizione magnetoreologica per autoveicoli. Considerando le caratteristiche di coppia trasmessa e potenza, il dispositivo è stato dimensionato tenendo presente i vincoli di ingombro del veicolo preso in esame. Sottoponendo il dispositivo ad analisi magnetostatica agli elementi finiti, si è determinato l’andamento delle linee di flusso del campo magnetico nel meato di fluido e nelle zone di maggior interesse, calcolando la coppia teoricamente trasmessa dall’innesto.È stato anche eseguito il confronto delle prestazionifra una frizione MR ed una frizione t…

Influence on the Dynamic Behavior of Full Car Equipped by Magnetorheological Damper via Switch on/off and h∞ Controller

2011

This paper shows the influence on dynamic behavior of the car when it is equipped with magneto-rheological dampers controlled by a feedback. The feedback is built up in two ways; the first is implemented by a switch on/off control that is characterized by the injection of magnetic field with a constant value. It happens when a certain value of relative speed between the sprung and unsprung mass is exceeded. The second feedback is characterized by the H-infinity control which is based on the relative displacement in order to vary the magnetic field signal in a continuous manner. At the same time the H-infinity control of vehicle is maintained by taking into account the exceeding of speed sig…

FABBRICAZIONE DI SENSORI ELETTROCHIMICI NANOSTRUTTURATI PER APPLICAZIONI NELL’INDUSTRIA ALIMENTARE E BIOMEDICHE

2023

USE OF SUPERCRITICAL CO2 AS DISSOLVED GAS FOR THE ATOMIZATION OF ETHANOL

2011

Supercritical dissolved gas atomization (SDGA) is an atomization process in which carbon dioxide at temperatures and pressures above its critical point is used as atomizing gas. In this work SDGA has been experimentally studied when ethanol is used as the liquid to be atomized. The spray characteristics in terms of droplets size and distribution have been investigated using a droplet size analyzer based on a laser diffraction method. Very narrow droplet size distributions were produced down to 2.5 μm. The main parameter that influences the droplets size is the gas to liquid mass ratio. From the point of view of the atomization mechanism, mean droplet diameter is mainly influenced by the two…

Turbulent heat transfer in spacer-filled channels: Experimental and computational study and selection of turbulence models

2019

Abstract Heat transfer in spacer-filled channels of the kind used in Membrane Distillation was studied in the Reynolds number range 100–2000, encompassing both steady laminar and early-turbulent flow conditions. Experimental data, including distributions of the local heat transfer coefficient h, were obtained by Liquid Crystal Thermography and Digital Image Processing. Alternative turbulence models, both of first order (k-e, RNG k-e, k-ω, BSL k-ω, SST k-ω) and of second order (LRR RS, SSG RS, ω RS, BSL RS), were tested for their ability to predict measured distributions and mean values of h. The best agreement with the experimental results was provided by first-order ω-based models able to …

Seroprevalence of Norovirus Genogroup IV Antibodies among Humans, Italy, 2010–2011

2014

Antibodies specific to genogroup IV identified in human specimens suggest zoonotic exposure.