Search results for "RME"

Transfer of Water and Active Molecules at the Interfaces in Complex Food Systems: Theoretical and Practical Aspects

2011

Abstract During processing, storage and consumption, mass transfer of various molecules (water, gases, flavour compounds or other solutes) occur between the different phases in complex food products, and/or also between the complex food and its surroundings. These mass transfers can lead to physical and/or chemical changes and thus induce food quality modifications. The objective of this presentation is to better understand the behaviour of small molecules at the interfaces, especially in model heterogeneous food systems. Different techniques have been developed to characterize their properties and their impact on the mass transfers. Particularly, techniques such as rotative diffusion cell …

Convective electrodiffusion processes through graft-modified charged porous membranes

1999

Convective diffusion and electrophoresis across a charged porous membrane showing variable permeability properties were studied. The membrane used was prepared by grafting poly(acrylic acid) (PAA) onto a porous polyvinylidene fluoride (PVDF) membrane. The degree of grafting was selected to be relatively low, 18 wt%, to compromise between the ion selectivity and hydraulic permeability of the membrane. The possible electric field induced effects on the membrane permselectivity were examined after the membrane had been characterized by convective diffusion and concentration cell potential measurements. The measured electrophoresis data, however, could be modelled using the extended Teorell–Mey…

Das erste persistenteβ-Silyl-substituierte Vinyl-Kation

1991

Use of semipermeable membrane devices for assessment of air quality in Tangier (Morocco)

2009

Semipermeable membrane devices (SPMDs) have been used for the evaluation of the contamination of air in both the urban and the industrial area in Tangier (Morocco). Benzene, toluene, ethylbenzene a...

Electrospray Ionization Mass Spectrometry Studies on the Mechanism of Hydrosilylation of Terminal Alkynes Using an N-Heterocyclic Carbene Complex of …

2006

A new pyridine-4,5-dichloroimidazol-2-ylidene complex of Ir(I) has been obtained, and its catalytic activity toward hydrosilylation of phenylacetylene and 4-aminophenylacetylene has been studied. T...

Current Developments in Industrial Fermentation Processes

2021

Dicopper(II) Metallacyclophanes with Oligo(p-phenylene-ethynylene) Spacers: Experimental Foundations and Theoretical Predictions on Potential Molecul…

2013

Two novel double-stranded dicopper(II) metallacyclophanes of formula (nBu4N)4[Cu2(dpeba)2]·4MeOH·2Et2O (1) and (nBu4N)4[Cu2(tpeba)2]·12H2O (2) have been prepared by the Cu(II)-mediated self-assembly of the rigid ('rod-like') bridging ligands N,N'-4,4'-diphenylethynebis(oxamate) (dpeba) and N,N'-1,4-di(4-phenylethynyl)phenylenebis(oxamate) (tpeba), respectively. Single crystal X-ray diffraction analysis of 1 confirms the presence of a dicopper(II)tetraaza[3.3]4,4'-diphenylethynophane metallacyclic structure featuring a very long intermetallic distance between the two square planar Cu(II) ions [r = 14.95(1) Å]. The overall parallel-displaced π-stacked conformation of the two nearly planar par…

Crystal structures of R2Pd2Pb (R = Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu) compounds

2004

Abstract The crystal structures of the R2Pd2Pb (R=Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu) compounds were determined using X-ray powder diffraction. The investigated compounds crystallize with Mo2FeB2 structure type (space group P4/mbm, Pearson code tP10). The importance of stabilization by polar intermetallic R–Pd bonding is underscored by a bonding analysis derived from electronic band structure calculations.

Chronological development of element concentrations in grapes during growth and ripeness and during fermentation of must determined by instrumental n…

2014

Abstract The chronological development of element concentrations during growth and ripeness of grapes described in the literature has only been concerned with the macro elements Mg, K, and Ca. Concentrations of trace elements in must are only described as a snapshot at the end of the ripeness. Therefore, the motivation for the present work was to accompany the growth and the ripening process of grapes successively by systematically determining element concentrations in grapes of Riesling and Cabernet Sauvignon by neutron-activation analyses. While for a number of elements, the concentrations in the grapes increased as a function of grape development (e.g., Na, K, Rb, Al), other concentratio…

EVALUACIÓN DE LA ACTIVIDAD ANTIINFLAMATORIA Y CITOTÓXICA DE ATRANORINA Y DILACTONA DEL ÁCIDO PULVÍNICO: COMPUESTOS FENÓLICOS BIOACTIVOS DEL LÍQUEN

2018

Parmelina tiliacea es una especie de liquen de Ecuador que ha sido poco estudiada en relación a sus potenciales aplicaciones. La investigación se llevó a cabo con el objetivo de establecer la actividad antiinflamatoria y citotóxica de P. tiliacea, mediante un método celular in vitro basado en el uso de una sal de tetrazolio solu- ble (WST-1) sobre neutrófilos aislados. Las moléculas de atranorina y dilactona del ácido pulvínico fueron aisladas del liquen P. tiliacea mediante métodos cromatográficos (cromatografía flash en columna y TLC). Los compuestos fueron identificados con la ayuda de estudios espectroscópicos (UV e IR), cromatográficos (TLC) y pruebas de identificación específicas para…