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71.
72.
Francisco J. Callado-Muñoz Jana Hromcová Natalia Utrero-González 《Computational Economics》2014,43(4):497-519
We study the relationship between openness and payment system development. In particular, we analyze how the existence of technology diffusion from a more developed country fosters a transformation of payment choice in a less developed country. We apply our analysis to Mexico. Economic growth in Mexico was not high enough to cause a transformation of payment choice observed in the data after 2001. We argue that the switch towards electronic payments can be attributed to openness and related payment technology spillovers from the US in the context of NAFTA. 相似文献
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Urszula Krupa-Kozak Natalia Drabińska Cristina M. Rosell Costantino Fadda Andrzej Anders Tomasz Jeliński Anita Ostaszyk 《International Journal of Food Science & Technology》2019,54(4):1121-1129
Broccoli by-products, in particular leaves, are rich sources of nutritional and bioactive components thus could constitute a valuable food additive. Although an upsurge in quantity of gluten-free products is observed further studies are required on improvement of their nutritional quality and palatability. This study aimed to investigate the influence of broccoli leaf powder (BLP) on dough behaviour, and technological characteristics and sensory quality of gluten-free mini sponge cake (GFS). Broccoli leaf powder replaced an equivalent amount (2.5%, 5%, 7.5%; w/w) of corn and potato starches in GFS formulation. Applied BLP increased the instrumental firmness of GFS but sensorial attributes (elasticity, crustiness, mastication and adhesiveness) were similar to the control. All broccoli GFS were vividly green, had small size pores properly distributed. Among them, sample with 2.5% BLP was distinguished for its desirable sensory quality, despite a slightly perceived cabbage aroma and taste. Moderate amount of BLP allows to preserve a good quality GFS improving its attractiveness and palatability. 相似文献
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The productivity of filtration systems for dewatering of finely dispersed suspensions can be increased by pulsating overpressure. For suspensions of marine organic‐mineral sediments, press filtration processes were investigated under static and pulsating overpressure. The influence of the static pressure component, the pressure amplitude characteristic, the pressure vibration frequency, and the filtration time on the volume of filtrate were determined. Based on Darcy's law, a model of the filtration process under static overpressure was developed. For pulsating overpressure, the mathematical theory of experiment planning and the statistical data analysis method were used. 相似文献
77.
Dmitry V. Volodkin Stephan Schmidt Paulo Fernandes Natalia I. Larionova Gleb B. Sukhorukov Claus Duschl Helmuth Möhwald Regine von Klitzing 《Advanced functional materials》2012,22(9):1914-1922
Formulation of therapeutic proteins into particulate forms is a main strategy for site‐specific and prolonged protein delivery as well as for protection against degradation. Precise control over protein particle size, dispersity, purity, as well as mild preparation conditions and minimal processing steps are highly desirable. It is, however, hard to fit all these criteria with conventional preparation techniques. Here a one‐step hard‐templating synthesis of microparticles composed of functional, non‐denatured protein is reported. The method is based on filling porous CaCO3 microtemplates with the protein near to its isoelectric point (pI) followed by pH‐ or EDTA‐mediated dissolution of the tempplates. In principle, a wide variety of proteins can be converted into microparticles using this approach. The main requirement is an overlap of the protein insolubility and a template solubility for a certain parameter (here pH or EDTA). Here the formulation of insulin particles is studied in detail and it is shown that particles consisting of high molecular weight protein (catalase) can also be prepared. In this context, the synthesis of CaCO3 templates with controlled size, the mechanism of the protein microparticle formation and mechanical properties of the microparticles are discussed. For the first time, the fabrication of mesoporous monodispersed CaCO3 microtemplates with identical porocity but tuned diameter from 3 to 20 μm is demonstrated. The protein particle diameter can be adjusted by choosing the appropriate template size that is critical for successful pulmonary delivery of insulin. As a first step towards insulin delivery, the in vitro release of insulin at physiological conditions is studied. 相似文献
78.
Natalia Veizaga José Fernandez Mariano Bruno Osvaldo Scelza Sergio de Miguel 《International Journal of Hydrogen Energy》2012,37(23):17910-17920
The objective of this study is to evaluate different methods to obtain Pt (20 wt%)/carbon electrocatalysts, in order to identify the conditions that lead to electrocatalysts with the best electrochemical performance. This paper involves the study of different methods for the deposition and reduction of H2PtCl6 on three carbon supports: Vulcan carbon, Multiwall carbon nanotubes and mesoporous carbons. The deposition–reduction methods in liquid phase were carried out with HCOOH or NaBH4 as reducing agents. Besides, the conventional impregnation was carried out by deposition of H2PtCl6 on carbon followed by a reduction with H2 at high temperature. The electrochemical performance of supported Pt catalysts prepared by reduction in liquid phase is strongly dependent on the metallic dispersion, the particle size distribution and the nature of the carbonaceous material used as a support. Results show that the deposition–reduction method using HCOOH 0.3 M at 50–60 °C and a mesoporous carbon leads to the most efficient electrocatalyst. 相似文献
79.
Natalia Brossard Beatriz Gonzalez-Muñoz Carolina Pavez Arianna Ricci Xinmiao Wang Fernando Osorio Edmundo Bordeu Giuseppina Paola Parpinello Jianshe Chen 《International Journal of Food Science & Technology》2021,56(10):5382-5394
Astringency is a sensory attribute, related to the quality and mouthfeel of red wines. However, the origin of astringency sub-qualities, such as the typical drying astringency found in immature grapes, is still unknown. Astringency of red wines with similar tannin content but different astringency sub-qualities, from different harvest dates, is studied. Astringency was characterised in terms of friction coefficient, polyphenol content, sensory analysis and tannin/salivary–proteins aggregates characterisation. A different evolution during ripening was found for both Cabernet Sauvignon and Carménère, and tannin–protein aggregates showed differences in size, shape and surface. The velvety sub-quality appears to be related to aggregates with low precipitation, and with specific surface characteristics as roundness and Feret diameter. Results from this work propose an effect of aggregates on sensory perception and opens the possibility to explore their effect on oral lubrication. 相似文献
80.
The combinatoric and topological analysis and modeling of the self-assembly of the Na26Cd141–hP168 crystal structure (space group Pbcm; a = 5.483 Å, b = 24.519 Å, and c = 14.573 Å; and V = 1895 Å3) are performed using computational methods (the ToposPro software package). Ninety-eight versions of the cluster representation of the 3D atomic network with the number of structural units ranging from four to seven are found. It is determined that polyhedral clusters–precursors C8 = 0@Na2Cd6 and C9 = 0@Na3Cd6 are templates, on the surface of which atomic shells consisting of 38 and 41 atoms are formed. The composition of the two-layer clusters is C46 = 0@(Na2Cd6)@(Na12Cd26) and C50 = 0@(Na3Cd6)@(Na6Cd35). The centers of clusters C46 and C50 are occupied by positions 1a with the symmetry 6/mmm and 2c with the symmetry −6m2. The symmetry and topology codes of the processes of self-assembly of 3D structures from nanoclusters–precursors C46 and C50 are reconstructed. 相似文献