Search results for "composition"
showing 10 items of 2675 documents
Expressing forest origins in the chemical composition of cooperage oak woods and corresponding wines by using FTICR-MS.
2008
A non-targeted, ultra-high-resolution mass spectrometric, direct analysis of oak-wood extracts from two species (Quercus robur L. and Quercus petraea Liebl.) from three French forests, and of a wine aged in barrels derived therefrom has been performed to identify families of metabolites that could discriminate both the species and the geographical origin of woods. From 12 T ultra-high-resolution Fourier transform ion cyclotron resonance mass spectra of wood extracts, hundreds of mass signals were identified as possible significant biomarkers of the two species, with phenolic and carbohydrate moieties leading the differentiation between Q. robur and Q. petraea, respectively, as corroborated …
Wine matrix composition affects temporal aroma release as measured by proton transfer reaction - time-of-flight - mass spectrometry
2015
This work was funded by the Ministerio de Economia y Competitividad (AGL2012-04172-C02-01), and Consolider Ingenio 2010 (Fun-C-Food, CSD2007-063, Projects). Dr Carolina Munoz-Gonzalez thanks Consejo Superior de Investigaciones Cientificas for its research contract co-funded by the European Social Fund together with Regional Council for Burgundy and Fondo Europeo de Desarrollo Regional (European Union) for experiments undertaken in Dijon, France.
Influence of bentonite fining on protein composition in wine
2017
Abstract Bentonite is the only fining agent which can stabilize wine and prevent protein haze formation after bottling. Currently many approaches are used to find an alternative because of bentonite's negative influence on color and aroma compounds. Nevertheless, the interaction of bentonite with wine proteins is not fully understood. Therefore, we analyzed the influence of a NaCa-combined bentonite on the protein content and composition of different wines showing a partial selectivity on protein adsorption. For example, glycosylated proteins were not removed by bentonite in notable amounts. Performing mass spectrometry we were able to demonstrate that 96% of class IV chitinase was adsorbed…
Searching the most appropriate sample pretreatment for the elemental analysis of wines by inductively coupled plasma-based techniques.
2008
Different sample preparation methods were evaluated for the simultaneous multielement analysis of wine samples by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Microwave-assisted digestion in closed vessel, thermal digestion in open reactor, and direct sample dilution were considered for the determination of Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Y, Mo, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Tl, Pb, and Bi in 12 samples of red wine from Valencia and Utiel-Requena protected designation of origin. ICP-MS allows the determination of 17 elements in most…
The influence of two different pH levels on the antioxidant properties of flavonols, flavan-3-ols, phenolic acids and aldehyde compounds analysed in …
2011
Abstract The aim of this study is evaluate either the antioxidant or pro-oxidant behaviour of some typical polyphenolic compounds of red wine, to investigate the influence of two different pH levels on the antioxidant properties and to clarify their activity–structure relationship. The antioxidant activity of compounds in hydrophilic solutions at pH 3.5 and pH 7.4 were measured by a competition kinetic test, based on the crocin bleaching. The position and the number of substitution groups influence the magnitude of the antioxidant activity of the polyphenolic compounds, but their antioxidant properties are also strongly influenced by the pH conditions. Increasing the pH, a considerable incr…
Research report: Interactions between toxic fatty acids for yeasts and colloids, cellulose and yeast ghost using the equilibrium dialysis method in a…
1997
Abstract The capacity of different materials (yeast walls, colloids and cellulose) to bind octanoic acid and decanoic acid was investigated in a model wine. The interactions between these toxic fatty acids and the soluble or insoluble material was shown using the equilibrium dialysis method. Yeast walls adsorb decanoic acid and to a lesser extent octanoic acid which confirms previous results. In comparison, colloids from both grape or yeast weakly bind decanoic acid and do not significantly bind octanoic acid. No interactions between cellulose and fatty acid were observed. According to the yeast wall composition, lipids seem to play a key role for binding. With regards to our results, the e…
THE SCUOLA OFFICINA MECCANICA IN VILLAGGIO MONTE DEGLI ULIVI IN RIESI. READING AND ANALYSIS THROUGH SURVEYING.
2017
This research analyses in depth the project of one of the most representative work of the Modern Architectural Movement in Sicily – the Scuola Officina Meccanica, located in Villaggio Monte degli Ulivi, in Riesi (CL), designed by the architect Leonardo Ricci between 1962 and 1968. The main objective is to contribute to the conservation of the architectural work through its analysis and study for a careful and conscious restoration. The research methodology aimed to retrace the compositional and geometric principles that defined the design process and its unique configuration.
D2 and H2 adsorption capacity and selectivity in CHA zeolites: Effect of Si/Al ratio, cationic composition and temperature
2020
International audience; The work deals with the effect of composition of CHA zeolites on the adsorption and separation of H2 and D2 under cryogenic temperatures. In the first part of this work the effect of Si/Al ratio and cationic composition on single gas adsorption of H2 and D2 was studied at 77.4 K. It was found that the adsorption capacities increase with Al content up to Si/Al = 2.1. Unexpectedly, Na-CHA zeolite with the highest Al content (Si/Al = 1.1) adsorbs only negligible amount because of the collapse of the zeolite structure upon dehydration at 400°C. The Na-and Li-containing chabazites with Si/Al = 2.1 possess similar adsorption capacities. In contrast, progressive replacement…
Peak capacity estimation in isocratic elution.
2008
Peak capacity (i.e. maximal number of resolved peaks that fit in a chromatographic window) is a theoretical concept with growing interest, but based on a situation rarely met in practice. Real chromatograms tend to have uneven distributions, with overlapped peaks and large gaps. The number of resolved compounds should, therefore, be known from estimations. Several equations have been reported for this purpose based on three perspectives, namely, the intuitive approach (peak capacity as the size of the retention time window measured in peak width units), which assumes peaks with the same width, and the outlines of Giddings and Grushka, which consider changes in peak width with retention time…
Spinodal decomposition of a two-dimensional model alloy with mobile vacancies
1991
Abstract Monte Carlo simulations are performed for the initial stages of phase separation in a model binary alloy (AB), where unmixing is caused by a repulsive energy between atoms of different kind ( e AA = e BB = e ), and a small fraction c v of mobile vacancies is present (typically c v = 0.04.) Unlike previous work, where interdiffusion was modelled in an unrealistic way by direct interchange of A and B atoms for c v = 0, were use the vacancy mechanism of diffusion: A-atoms may jump to vacant sites with a rate Γ A and B-atoms may jump to vacant sites with a rate Γ B , no direct A–B interchange being permitted. It is shown that the overall time-scale on which phase separation proceeds ty…