Search results for "dynamics."
showing 10 items of 9637 documents
Experimental Determination and Correlation of Liquid–Liquid Equilibria Data for a System of Water + Ethanol + 1-Butyl-3-methylimidazolium Hexafluorop…
2017
Over the past few years, interest has increased regarding the application of ionic liquids (ILs) as extraction solvents for separating azeotropic mixtures. Following this trend, this work presents the experimental data of liquid–liquid equilibria (LLE) of the system envolving water, ethanol, and 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) at different temperatures. The LLE data of the system was measured between 283.2 and 323.2 K to determine the temperature influence on the system. In the literature, reports of systems involving ILs that present type II behavior are scarce compared with those that present type I behavior; the system presented here also displays two immisc…
Liquid–liquid equlibria of the system dimethyl carbonate+methanol+water at different temperatures
2006
Abstract In this work, experimental liquid–liquid equilibria (LLE) data of the dimethyl carbonate + methanol + water system are presented. The LLE of this system has been measured from 283 to 333 K. On the other hand, LLE and LVE of the binary system dimethyl carbonate + water have been measured. The equilibrium data presented are correlated using NRTL and UNIQUAC equations. The reliability of these models is tested by comparison with experimental results. Finally, the VLE for the system DMC + water at 101.3 kPa was predicted using the UNIQUAC model, with the adjusted parameters obtained from the LLE data. This prediction was successful when is compared with the experimental VLE data.
Extended Validation of Dynamic Irreversible Thermoporation: A Novel Thermal Process for Microbial Inactivation
2015
A novel thermal treatment for microorganism inactivation, characterized by a very rapid temperature increase (up to 30°C/s) and a low final temperature (up to 65°C) maintained for a relatively short holding time, has been recently presented and tested by the authors, showing microbial load reduction greater than 5 log units against several common bacteria and yeasts. With the aim of extending the possible use of the new thermal treatment to a wider microorganisms class, in this work the dynamic irreversible thermoporation (DIT) treatment was further tested on a well-known thermoresistant strain, the Enterococcus hirae: The results of these new experimental tests confirmed the reliability of…
Heterogeneous kinetics: from solid–gas reaction to solid–liquid dissolution
2002
Abstract The extension of the formal kinetics of solid–gas reactions to solid–liquid dissolution is investigated theoretically. The work is based on modelling the dissolution of a solid in a closed system by a stoichiometrically simple chemical reaction A solid ⇄A liquid proceeding up to either an equilibrium state if the solid phase is initially in excess or exhaustion in the reverse situation. The initial amount of solid compared to the capacity of the liquid phase appears as a major factor of complexity. First, the rate equation is formulated in terms of the intensive variables without any assumption about the mechanism and the rate-limiting step. The resulting equations are compared to …
Early stages of beta2-microglobulin aggregation and the inhibiting action of alphaB-crystallin
2008
The interest of nucleation of protein crystals and aggregates (including oligomerization) spans from basic physics theory all the way to biophysics, nanophysics, clinical sciences, biotechnologies, food technologies and polymer-solvent interactions. Understanding nucleation within a theoretical framework capable of providing quantitative predictions and control of nucleation rates, or even the very occurrence of crystallization, is a long-sought goal of remarkable relevance to each of the above fields. A large amount of work has been aimed at such goal, but success has been so far rather limited. Work at our laboratory has more recently highlighted a direct link between nucleation rates and…
Ageing of isotactic polypropylene due to morphology evolution, experimental limitations of realtime density measurements with a gradient column
2006
Abstract Ageing in crystalline polymers is responsible for the deterioration of physical properties leading, for example, to a decrease in toughness and to dimensional changes that are to some extent responsible for warpage and scrap production in injection molding. Since, it depends on the mutual transformation of stable and metastable phases, being always related to changes in morphological organization, it is here preferred to call it ‘Morphological ageing’. Although, one would expect the ageing regime to be determined by the complex morphology with amorphous phases of different mobility and eventually multiple crystalline phases, transformed into each other at an associated transition, …
Liquid–liquid equlibria of the mixture linalool+ethanol+water at different temperatures
2005
Abstract In this work, experimental liquid–liquid equilibria (LLE) data of the linalool + ethanol + water system are presented. The LLE of this system has been measured at 293.15, 303.15, 313.15 and 323.15 K. The equilibrium data presented are correlated using NRTL and UNIQUAC equations. Finally, the reliability of these models is tested by comparison with experimental results.
Measurements and correlation at different temperatures of liquid–liquid equilibria of 2-butanol or 2-methyl-2-butanol+1,2,3-propanetriol+water ternar…
2014
Abstract In this work, the experimental liquid–liquid equilibria (LLE) data of 2-methyl-2-butanol + 1,2,3-propanetriol (glycerol) + water and 2-butanol + 1,2,3-propanetriol (glycerol) + water systems at different temperatures are presented. The LLE of the systems has been measured between 283 and 323 K. The NRTL and UNIQUAC models were applied to the ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The experimental tie lines were compared to the values predicted by the UNIFAC method. Finally, the solvent capability of both alcohols was checked in order to separate the mixture formed by glycerol and water.
Wireless power transfer system stability analysis for E-bikes application
2019
The present work reports the stability analysis of an Inductive Coupled Power Transfer (ICPT) System coupled to an electrical bike. The study has focused on two coupled coils with circular geometry and vertical disposition. In the first part of the work, the theoretical aspects related to the stability of wireless power systems are handled. In the second part, performing several simulations, varying the features of the considered configuration, the stability is looked for. In order to perform this process, the Ansys Maxwell software has been used, performing 3D simulations.
Heat to electricity conversion by cold carrier emissive energy harvesters
2015
This paper suggests a method to convert heat to electricity by the use of devices called cold carrier emissive energy harvesters (cold carrier EEHs). The working principle of such converters is explained and theoretical power densities and efficiencies are calculated for ideal devices. Cold carrier EEHs are based on the same device structure as hot carrier solar cells, but works in an opposite way. Whereas a hot carrier solar cell receives net radiation from the sun and converts some of this radiative heat flow into electricity, a cold carrier EEH sustains a net outflux of radiation to the surroundings while converting some of the energy supplied to it into electricity. It is shown that the…