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61.
J. Rodríguez‐Ramírez L. Mndez‐Lagunas A. Lpez‐Ortiz S. Sandoval Torres 《Journal of food science》2012,77(12):R146-R154
Abstract: This review presents the concepts involved in determining the density of foodstuffs, and summarizes the volumetric determination techniques used to calculate true density and apparent density in foodstuffs exposed to the drying process. The behavior of density with respect to moisture content (X) and drying temperature (T) is presented and explained with a basis in changes in structure, conformation, chemical composition, and second‐order phase changes that occur in the processes of mass and heat transport, as reported to date in the literature. A review of the empirical and theoretical equations that represent density is presented, and their application in foodstuffs is discussed. This review also addresses cases with nonideal density behavior, including variations in ρs and ρw as a function of the inside temperature of the material, depending on drying conditions (X, T). A compilation of studies regarding the density of dehydrated foodstuffs is also presented. 相似文献
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Valesca Cristiane Benelli Francisco Clarissa Hamaio Okino-Delgado Mirella R. Zanutto Elgui Célio Junior da Costa Fernandes Roselaine Facanali Rodrigo Augusto da Silva Willian Fernando Zambuzzi Márcia Ortiz Mayo Marques Luciana Francisco Fleuri 《International Journal of Food Science & Technology》2019,54(4):1089-1099
The aim of this study was to show that abundant and inexpensive plant oils can be biotransformed to increase biological activity (antioxidant, antimicrobial and cytotoxicity) through hydrolysis reaction catalysed by lipases. We tested homemade and commercial lipases through the biotransformation of nine different plant oils in forty different combinations. First, the chemical composition of the samples was investigated. Thereafter, biological tests were conducted to assess the antioxidant and antimicrobial activity of the sampled biotransformation products, as well as analyzed their influence on the viability of healthy and cancer cells. Summarising, sunflower, corn and olive oils modified by orange waste-obtained lipases presented the most promising results, reaching up to 90% of antioxidant activity increase and significant growth inhibition of bacteria colonies belonging to genera Escherichia, Listeria, Staphylococcus, Pseudomonas and Salmonella. In addition, those compounds affected human oral squamous carcinoma cells. The bioconversion of plant oils through lipases improves their biological properties and might be an option for biotechnological application. 相似文献
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The objective of this paper was to investigate the regional incidence of the aggregate effects of investment in highways in the US taking into consideration the presence of regional spillovers. The empirical results are based on VAR estimates at both the aggregate and state levels using output, employment, and investment, as well as different measures of highway investments. Empirical results allow us to establish several stylized facts. First, investment in highways affects private sector variables positively at the aggregate level as well as in most states. Second, the regional spillover effects are very significant for all private sector variables. Third, these spillovers have a clear geographical pattern in that they tend to be more important in western states and the corridor between the Great Lakes and the Gulf Coast. 相似文献
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Marco Cariglia Alfredo Vargas-Paredes Mauro M. Doria Antonio Bianconi Milorad V. Milošević Andrea Perali 《Journal of Superconductivity and Novel Magnetism》2016,29(12):3081-3086
Ultrathin superconductors of different materials are becoming a powerful platform to find mechanisms for enhancement of superconductivity, exploiting shape resonances in different superconducting properties. Here, we evaluate the superconducting gap and its spatial profile, the multiple gap components, and the chemical potential, of generic superconducting nanofilms, considering the pairing attraction and its energy scale as tunable parameters, from weak to strong coupling, at fixed electron density. Superconducting properties are evaluated at mean field level as a function of the thickness of the nanofilm, in order to characterize the shape resonances in the superconducting gap. We find that the most pronounced shape resonances are generated for weakly coupled superconductors, while approaching the strong coupling regime the shape resonances are rounded by a mixing of the subbands due to the large energy gaps extending over large energy scales. Finally, we find that the spatial profile, transverse to the nanofilm, of the superconducting gap acquires a flat behavior in the shape resonance region, indicating that a robust and uniform multigap superconducting state can arise at resonance. 相似文献
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Angelica B. Ortiz de Gortari Mark D. Griffiths 《International journal of human-computer interaction》2016,32(6):470-480
Previous qualitative studies suggest that gamers experience Game Transfer Phenomena (GTP), a variety of non-volitional phenomena related to playing videogames including thoughts, urges, images, and sounds when not playing. To investigate (i) which types of GTP were more common and (ii) their general characteristics, the present study surveyed a total of 2362 gamers via an online survey. The majority of the participants were male, students, aged between 18 and 27 years, and “hard-core” gamers. Most participants reported having experienced at least one type of GTP at some point (96.6%), the majority having experienced GTP more than once, with many reporting 6 to 10 different types of GTP. Results demonstrated that videogame players experienced (i) altered visual perceptions, (ii) altered auditory perceptions, (iii) altered body perceptions, (iv) automated mental processes, and (v) behaviors. In most cases, GTP could not be explained by being under the influence of a psychoactive substance. The GTP experiences were usually short-lived, tended to occur after videogame playing rather than during play, occurred recurrently, and usually occurred while doing day-to-day activities. One in five gamers had experienced some type of distress or dysfunction due to GTP. Many experienced GTP as pleasant and some wanted GTP to happen again. 相似文献
70.
Systematic studies have been performed to investigate the composition effects of ZrO2-based thermal barrier coating (TBC) ceramics on their interactions with molten Ca–Mg–Al–silicate (CMAS) glass. Porous ceramic pellets (~15% porosity), instead of actual TBCs, are used in these model studies, where the penetration of molten CMAS into the pellets is investigated. This study involves a total of six compositions of ZrO2-based ceramics: two containing low solute (Y3+ or Gd3+) concentration, three with high concentration of solute (Y3+, Gd3+ or Yb3+), and one containing a combined intermediate concentration of Y3++Al3++Ti4+ solutes. While both the type of the solute and its concentration in the ZrO2-based TBC ceramics have been found to influence the extent of molten CMAS penetration into the pellets, the solute concentration has the most dramatic effect. In particular, molten CMAS penetration is almost completely suppressed in porous TBC ceramic pellets containing a high concentration of Y3+ solute (Y2Zr2O7). Possible mechanisms governing these effects are presented, together with a discussion of guidelines for the chemical design of CMAS-resistant zirconate TBC ceramics. Generally, for a TBC ceramic to be highly effective against CMAS attack it must interact vigorously with the molten CMAS, which must result in the rapid crystallization of the refractory oxide phase(s) that form a sealing layer, arresting further penetration of the molten CMAS. The porous ceramic pellets approach used here could be developed into rapid-screening methodologies for the discovery of CMAS-resistant TBC ceramic compositions, and to study the effect of composition of CMAS glasses on their interactions with TBC ceramics of specific compositions. 相似文献