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91.
Santiago Bascuas Isabel Hernando Gemma Moraga Amparo Quiles 《International Journal of Food Science & Technology》2020,55(4):1458-1467
Edible oleogels, with three oil types (olive, sunflower and flaxseed), hydroxypropylmethylcellulose (HPMC) and xanthan gum (XG), as structuring agents, were developed using the emulsion-template approach, and subsequent drying of the emulsions using conventional or vacuum drying. Our results showed that for both drying methods, well-structured oleogels were obtained using olive and sunflower oils for the preparation. These oleogels showed oil losses ˂10% after 35 days of storage. However, unstructured non-homogeneous oleogels were obtained when using flaxseed oil and conventional drying, while it was not feasible to develop flaxseed oleogel with vacuum drying. Oleogels showed interesting rheological properties, including a high oleogel strength with an elastic modulus of the order 104–105 Pa, weak dependence on frequency, and good thermostability. Moreover, high oxidative stability was obtained for olive oil oleogels, using both conventional and vacuum drying, and for sunflower oleogels using vacuum drying. Still, the initial oxidation rates of sunflower oleogels using conventional drying should be improved in future studies. 相似文献
92.
Moiss Silva Cervantes Ana Hernando Antonio García‐Abril Rubn Valbuena Javier Velzquez Saornil Jos Antonio Manzanera 《河流研究与利用》2020,36(7):1307-1320
The space–time dynamics and the effect of urban growth on territory transformation were simulated with Iber 2D to analyze flooding events in the lower basin of the Sabinal River, Mexico. We classified the main coverages and land uses of the study area. Soil roughness and water infiltration in the soil were evaluated. Both values were used as input data in a simulation model with Iber 2D to analyze and compare the levels of water height and maximum flood level area with different precipitation values in two reference years, 1986 and 2014. Residential use land cover increased considerably while tree, pasture and agricultural use covers decreased. Consequently, in 2014, precipitation of similar magnitude led to higher values of direct runoff, increasing water levels and therefore the risk of overflowing. The water levels and moments of river overflow provided feedback for flood‐risk warning systems and tools to monitor basins lacking adequate infrastructure. 相似文献
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Kuantay Boshkayev Hernando Quevedo Saken Toktarbay Bakytzhan Zhami Medeu Abishev 《Gravitation and Cosmology》2016,22(4):305-311
We study stationary axially symmetric solutions of the Einstein vacuum field equations that can be used to describe the gravitational field of astrophysical compact objects in the limiting case of slow rotation and slight deformation. We derive explicitly the exterior Sedrakyan–Chubaryan approximate solution, and express it in an analytical form, which makes it practical in the context of astrophysical applications. In the limiting case of vanishing angular momentum, the solution reduces to the well-known Schwarzschild solution in vacuum. We demonstrate that the new solution is equivalent to the exterior Hartle–Thorne solution. We establish mathematical equivalence between the Sedrakyan–Chubaryan, Fock–Abdildin and Hartle–Thorne formalisms. 相似文献
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Why Are “Others” So Polarized? Perceived Political Polarization and Media Use in 10 Countries 下载免费PDF全文
JungHwan Yang Hernando Rojas Magdalena Wojcieszak Toril Aalberg Sharon Coen James Curran Kaori Hayashi Shanto Iyengar Paul K. Jones Gianpietro Mazzoleni Stylianos Papathanassopoulos June Woong Rhee David Rowe Stuart Soroka Rodney Tiffen 《Journal of Computer-Mediated Communication》2016,21(5):349-367
This study tests the associations between news media use and perceived political polarization, conceptualized as citizens' beliefs about partisan divides among major political parties. Relying on representative surveys in Canada, Colombia, Greece, India, Italy, Japan, South Korea, Norway, the United Kingdom, and the United States, we test whether perceived polarization is related to the use of television news, newspaper, radio news, and online news media. Data show that online news consumption is systematically and consistently related to perceived polarization, but not to attitude polarization, understood as individual attitude extremity. In contrast, the relationships between traditional media use and perceived and attitude polarization is mostly country dependent. An explanation of these findings based on exemplification is proposed and tested in an experimental design. 相似文献
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F Soriguer S Serna E Valverde J Hernando A Martín-Reyes M Soriguer A Pareja F Tinahones I Esteva 《Canadian Metallurgical Quarterly》1997,13(4):451-463
We undertook a systematic evaluation of the lipid, protein, calorie, and fatty acid composition in 35 species of fish, shellfish and molluscs commonly consumed throughout the four seasons of the year in Andalusia, Spain. Using a portion of muscle tissue the following were measured in each study unit: total lipids (extraction using Folch's method and gravimetry), protein concentration (Kjehldal's method), total calories (direct calorimetry), and composition of fatty acids (gas chromatography). The lipid, protein, and different fatty acid concentrations found are presented in table form. There was a high degree of inter-species variability in the concentration of lipids and the various fatty acids. There was also a high degree of intra-species seasonal variability in some cases. The relative proportion of fatty acids was not independent of the total concentration of lipids, independently of the season studied. This systematic study of a large group of species shows that the cataloguing of fish as 'white' or 'blue' depends especially on the time of year they are captured. For example, in spring the mackerel (Scomber scombrus), a fish considered traditionally to be 'blue' (fatty), has the same lipid concentration as the dover sole (Solea vulgaris), commonly considered to be 'white' (little fat), and the sea pike (Merluccius merluccius) has a higher lipid concentration in autumn than the jack mackerel (Trachurus trachurus). Even greater differences existed when the fish were classified according to their richness in n-3 fatty acids. These differences in the total lipid concentration and the composition of fatty acids, as well as the inter-relations between them, may, under certain circumstances, be important for the calculation of dietary calories and nutritional values, and may explain the differences found between the various tables of food composition, as well as the divergent results in epidemiological studies on the association between fish in diets and various diseases, such as diabetes or ischaemic cardiopathy. 相似文献
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