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排序方式: 共有2164条查询结果,搜索用时 31 毫秒
1.
Macintosh Katrina A. McDowell Richard W. Wright-Stow Aslan E. Depree Craig Robinson Guy M. 《Nutrient Cycling in Agroecosystems》2021,120(2):121-129
Nutrient Cycling in Agroecosystems - Reducing agriculturally derived diffuse contaminant losses (via non-point sources) from land to water has proven difficult for decades. Owing to the diversity... 相似文献
2.
Elnaz Shahbazali Emilie M. F. Billaud Arash Sarhangi Fard Jan Meuldijk Guy Bormans Timothy Noel Volker Hessel 《American Institute of Chemical Engineers》2021,67(1):e17067
Liquid-phase adsorption has hardly been established in micro-flow, although this constitutes an industrially vital method for product separation. A micro-flow UV-photo isomerization process converts cis-cyclooctene partly into trans-cyclooctene, leaving an isomeric mixture. Trans-cyclooctene adsorption and thus separation was achieved in a fixed-bed micro-flow reactor, packed with AgNO3/SiO2 powder, while the cis-isomer stays in the flow. The closed-loop recycling-flow has been presented as systemic approach to enrich the trans-cyclooctene from its cis-isomer. In-flow adsorption in recycling-mode has hardly been reported so that a full theoretical study has been conducted. This insight is used to evaluate three process design options to reach an optimum yield of trans-cyclooctene. These differ firstly in the variation of the individual residence times in the reactor and separator, the additional process option of refreshing the adsorption column under use, and the periodicity of the recycle flow. 相似文献
3.
Nielsen Guillaume Coudert Lucie Janin Amelie Blais Jean Francois Mercier Guy 《Mine Water and the Environment》2019,38(1):104-118
Mine Water and the Environment - Acid mine drainage (AMD) is a major environmental challenge for the mining industry in northern climates. Laboratory-scale experiments were conducted to test... 相似文献
4.
Melissa Assad-Bustillos Juliette Palier Hanitra Rabesona Yvan Choiset Guy Della Valle Gilles Feron 《Journal of texture studies》2020,51(1):134-143
This study investigated the digestibility of proteins in a pea protein-fortified sponge cake, as well as the impact of the degree of structure of the bolus produced by elderly subjects on the digestibility of proteins by combining ex vivo and in vitro approaches via the standardized protocol INFOGEST. The sponge cakes were consumed by a group of 20 elderly subjects with contrasting physiology, their boli were recovered just before swallowing, and their apparent viscosity was measured to delineate the bolus degree of structure. According to this criterion, two pools were formed with boli from subjects selected at the extremes: low viscosity and high viscosity, with apparent viscosity values (at 120 s−1) of 124 ± 18 and 208 ± 19 Pa s, respectively. The sponge cakes and the two pools underwent in vitro digestion. Protein hydrolysis kinetics was followed by measuring the released primary amino groups (NH2) and by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis at different time points. For all samples, the representative bands of pea proteins disappear gradually during digestion, accompanied by the appearance of bands indicating the presence of proteins with MW < 15 kDa. In addition, the NH2 concentrations increase over time and do not differ between sponge cake and pea protein isolate. Moreover, the degree of structure of the food bolus has no significant effect on the concentration of NH2 released. These results showed that pea proteins in a fortified sponge cake are bioaccessible under standardized conditions and that the degree of structure of the bolus did not influence protein digestibility for these foods. 相似文献
5.
Graded evolution of anisotropic microstructure during sintering from crystal-oriented powder compact
Shoko Baba Alexandre Maître Nicolas Pradeilles Guy Antou Nobuo Saito Satoshi Tanaka 《International Journal of Applied Ceramic Technology》2020,17(2):677-684
Anisotropic sintering, including shrinkage and grain growth, was examined for c-axis-oriented (Sr,Ca)2NaNb5O15 (SCNN) ceramics, which were prepared by colloidal processing under a magnetic field. In the c-axis-oriented SCNN powder compact, shrinkage and grain growth along the c-axis were higher than those along the a-axis. The anisotropic microstructural development was clearly associated with anisotropic sintering shrinkage. X-ray diffraction, scanning electron microscopy, and energy back scattering diffraction showed that the grain growth of oriented particles by including random grains contribute to the development of the oriented microstructure. Finally, the highly crystal-oriented SCNN ceramics with a densified microstructure were obtained through anisotropic sintering. These results clearly showed the potential to develop a well-defined anisotropic microstructure during sintering by designing and controlling the particle packing structure in a powder compact. 相似文献
6.
7.
Rosana Fatima Galindo Luis Antonio Barbosa Cortez Telma Teixeira Franco 《化学工程与技术》2020,43(8):1530-1537
An alternative for reducing emissions from marine fuel is to blend bio-oil from lignocellulose non-edible feedstocks to diesel fossil fuels. Phase diagrams of the ternary systems were built to represent the transition from heterogeneous regions to homogeneous regions. Four homogeneous blends of bio-oil of eucalyptus-bioethanol-marine gasoil were experimentally characterized with respect to the most important fuel parameters for marine engines: water content, flash point, low heating value, viscosity, and acidity. Blends with closer properties to marine gasoil replacement, lower costs, and environmental impacts should be tested for large engines. 相似文献
8.
9.
Gilbert Rodríguez Eudes Villanueva Danco Cortez Esther Sanchez Elza Aguirre Alyssa Hidalgo 《Journal of the American Oil Chemists' Society》2020,97(7):729-735
Chia and sesame oils are important sources of essential fatty acids; however, their ω-3:ω-6 proportions do not comply with nutritional recommendation. A feasible approach to improve the ratio is to blend different oils, but only after understanding physical and chemical changes of the new matrix. Objective of the investigation was to determine the physico-chemical characteristics and the oxidative stability index (OSI), using the Rancimat method, of chia-sesame oil blends. The four ω-3:ω-6 blends tested (1:4, 1:6, 1:8, and 1:10) were exposed to temperatures of 110, 120, and 130 °C. The OSI values of the mixtures varied between 6.24–8.08, 3.07–4.00, and 1.62–2.01 hours for each temperature, respectively. In addition, their mean activation energy, enthalpy, entropy, and Q10 were 88.4 kJ/mol, 85.2 kJ/mol, −41.1 J/mol K, and 2.0. Finally, a shelf life prediction performed at 25 °C indicated stability times between 80 and 123 days. Therefore, combining chia and sesame oils produced blends with a good balance of essential fatty acids. 相似文献
10.
Barbara Walther Aaron M. Lett Alessandra Bordoni Lidia Toms‐Cobos Juan Antonio Nieto Didier Dupont Francesca Danesi Danit R. Shahar Ana Echaniz Roberta Re Aida Sainz Fernandez Amlie Deglaire Doreen Gille Alexandra Schmid Guy Vergres 《Molecular nutrition & food research》2019,63(21)
Nutritional research is currently entering the field of personalized nutrition, to a large extent driven by major technological breakthroughs in analytical sciences and biocomputing. An efficient launching of the personalized approach depends on the ability of researchers to comprehensively monitor and characterize interindividual variability in the activity of the human gastrointestinal tract. This information is currently not available in such a form. This review therefore aims at identifying and discussing published data, providing evidence on interindividual variability in the processing of the major nutrients, i.e., protein, fat, carbohydrates, vitamins, and minerals, along the gastrointestinal tract, including oral processing, intestinal digestion, and absorption. Although interindividual variability is not a primary endpoint of most studies identified, a significant number of publications provides a wealth of information on this topic for each category of nutrients. This knowledge remains fragmented, however, and understanding the clinical relevance of most of the interindividual responses to food ingestion described in this review remains unclear. In that regard, this review has identified a gap and sets the base for future research addressing the issue of the interindividual variability in the response of the human organism to the ingestion of foods. 相似文献