1,721,001 research outputs found
Membrane techniques for the product quality and identity
No full textIn this work performances of different membrane techniques have been studied: reverse osmosis, nanofiltration and membrane contactors applied to must and wines. Different rejections of several membranes have been evaluated.
The results highlighted a great variability of different materials, therefore allow the development of different processes and
aimed at separation process.
The experiences made with the contactors has allowed us to verify the de-alcoholization process and the volatile acidity removal from the wines, without any wine fractioning.
The combination of this techniques can be also interesting, especially in combination with other separation process. The challenge now is to evaluate the deontological ethics, not for the
single phase in which the process can be applied, but to the aim achievable, out of all is strategic the concrete perspective to guarantee the territorial identit
A preliminary comparison between nanofiltration and reverse osmosis membranes for grape juice treatment
No full textNanofiltration (NF) and reverse osmosis (RO) systems were compared using grape juice as feed solution. The initial permeate flux (J) was 7.4, 8.1, and 1.7dm3 m-2 h-1 with NF membranes DS and DK, and RO membrane SWC, respectively. The exponential decay of J in the above NF and RO membranes was characterized by a fouling index equal to 0.16, 0.22, and 0.24, respectively. The permeability of NF membrane DS doubled by increasing the working pressure from 32 to 45 bar. Despite the additional power (+30%) required to work at the higher pressure value there was an energy saving per unit permeate of approximately 35%. The working pressure and temperature affected the selectivity of NF membranes. As expected, a direct relationship between membrane permeability and working temperature occurred; the permeate flux of NF membrane DS increased by about 3% per degree of temperature rise. © 2001 Elsevier Science Ltd. All rights reserved
The determination of total SO2 in grape juice. A comparison among five methods
No full textThe EC official method of total SO2 analysis in grape juice was modified in 1990. The main improvements concerned the amount and concentration of H3PO4 used during the distillation to recover the combined SO2 and the standardization of the distillation time at 15 min. This comparative study evaluated the total SO2 level of 12 grape juices determined by five methods, including distillation, iodimetric and enzymatic-based methods. Attention was focused on the total SO2 legal limit of 10mg/l fixed in Europe for grape juice. Analysis of variance disclosed a significant difference among the total SO2 content in grape juices determined by five methods. Each analytical method showed limits in relation of their ability to release the combined SO2. In particular, the SO2 bonded to phenolic compounds is partially released at low pH in the acidified juice leading to higher results
Il confezionamento a freddo delle bevande: proposte per incrementarne le caratteristiche di qualita' e sicurezza
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
