1,721,011 research outputs found
Development of functional coatings for different applications: from food packaging to fashion industry
No full textCoatings are important in our society due to their contribution in terms of safety, health, comfort and well-being, for example, by offering protection from external agents to buildings, infrastructures, transports, food, and textiles. Since in our life most of the time we are in direct contact with them, for example in the shoes that we wear or in the food that we eat, it is essential that the materials used to develop the coatings are not toxic for our health. In addition,
nowadays, the coating research-field and industry are looking for solutions to improve the sustainability of materials (e.g. biosourced, biodegradable, renewable materials) and processes (e.g. energy efficient manufacturing) in order to reduce their impact on the environment [1]. In this contest, the main objective of this work is to select sustainable materials in order to develop functional coatings for different applications, such as food packaging and leather industry. Concerning the food packaging, one of the main trend is to develop antimicrobial active coatings to reduce or avoid the bacterial growth on food, preserving its quality for a longer a time [2]. For this reason, a food grade sustainable copolymer and an antioxidant molecule, curcumin, have been combined to develop a sustainable and active coating for various substrates such as glass and polysaccharide films with the aim of proposing a coating
for food packaging [3]. Due to the application, the coating presents appealing properties, such as reduction of gas exchange between the inside and the outside of the packaging, as well as transparency to allow the visibility of the food, and UV-filtering ability to protect the food from the UV light. Last but not least, the coating is characterized by low bacterial adhesion, making it a possible candidate for active food packaging. Since the challenge of finding sustainable and green solutions for low environmental impact coatings has been evolving from avoiding petroleum-derivatives into the opportunity to get materials derived from renewable resources and waste [4], in this work, as next step, by-products of the food industry have been taken in consideration to develop a hydrophobic and water resistant coating for fish leather. Since salmon fish skin is one of the main waste of the aquaculture, the Horizon 2020 project, FISHSKIN [5], has considered it a sustainable raw material for fashion transforming it into leather. In this contest, the coating for fish leather has been developed by using the epoxidized soybean oil, which derives from the soybean oil produced in excess in many geographical areas respect to the consumption in cooking [6], and a sustainable trimer acid. As a result, it improved the waterproof ability of the leather in terms of water and humidity without affecting itsbreathability and softness. Both the developed coatings could be easily scalable in an industrial process and considered as possible solutions in their fields of application, firstly because they respect the sustainability goal as main aim of the industries. In addition, the curcumin-based coating could be easily applied on different substrates, such as paper, PET and other food packaging materials, as well as the ESO-based coating could make water resistant cotton, as demonstrated, or other functional materials, such as paper, used also in other fields of application
Hydrophobic and water resistant fish leather: a fully sustainable combination of discarded biomass and by-products of the food industry
Get PDFThe food industry produces a large amount of food byproducts that, when appropriately valorized, can become a renewable source of sustainable materials. The valorization of these byproducts requires a new set of green technologies. For example, fish farming, one of the fastest growing sectors, uses only 30% to 40% of the fish as food, with the remaining 60% to 70% being a byproduct. One example of valorization of fish byproducts is the upcycling of fish skin into leather. This new fish leather has interesting properties, in part due to its microstructure, but also has new shortcomings like the high hydrophilicity and water absorption. To mitigate these issues, a water protecting coating was developed using only two other food byproducts: epoxidized soybean oil and the fatty acid trimer Pripol. These two building blocks were deposited on leather and then crosslinked to create a strong network that made leather hydrophobic, with a water contact angle >120° without the need for fluorine or silicone chemistry or the use of nanoparticles. The coating was applied via dip-coating and was cured at low temperature as required by fish leather without the need for initiators, catalysts, which are mostly toxic, or UV light. The same strategy could also be applied to cotton, showing that its application is not limited only to leather. The coating showed good adhesion to the substrate and excellent water resistance, making the leather and the cotton hydrophobic and substantially reducing the water absorption, without changing the breathability, flexibility and microstructure of the substrate. This work demonstrates how high performing materials can be created within a green chemistry and circular economy framework, with results that can be relevant for other textile materials, contributing to the effort for developing sustainable alternatives for providing hydrophobicity
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Antioxidant coatings from elastomeric vinyl acetate-vinyl laurate copolymers with reduced bacterial adhesion
No full textA vinyl laurate-based elastomeric copolymer, developed as chewing gum base, was used to produce functional coatings with the antioxidant curcumin. Both the polymer and curcumin were dissolved in MIBK, methyl isobutyl ketone. Coatings were applied on glass but also on natural alginate and gelatin film surfaces by dip-coating. Microscopy analysis indicated that coatings had very homogenous surface and curcumin was effectively encapsulated within the polymeric matrix. In addition, curcumin-laden coatings (10 wt%) remained transparent with excellent UV filtering properties. The flexibility of alginate and gelatin films was maintained after coating, whereas their hydrophobicity and water vapor barrier properties improved. Furthermore, coating biocompatibility and low bacterial adhesion properties were confirmed by cell proliferation and bacterial surface contamination experiments, respectively. The radical scavenging activity of the coating was assessed with both DPPH and ABTS assay, revealing effective antioxidant properties. In addition, in weak acetic acid solutions, curcumin could be released in a sustained manner from the coatings. This coating can be used as a suitable option for improving the antioxidant and bacterial resistance properties of natural polymer films including food packaging or other relevant applications
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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