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排序方式: 共有1874条查询结果,搜索用时 15 毫秒
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Chatterjee Gaurav Latorre Laurent Mailly Frédérick Nouet Pascal Hachelef Nacim Oudea Coumar 《Microsystem Technologies》2017,23(9):3969-3978
Microsystem Technologies - Inertial measurement units (IMU) are essentially a combination of acceleration and rotation rate sensors, generating position and attitude information. For tactical and... 相似文献
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Houshang D. Alamdari Dominique Dub�� Pascal Tessier 《Metallurgical and Materials Transactions A》2013,44(1):388-394
The mechanism of heterogeneous grain refining of aluminum by ultrafine elemental boron particles was investigated. In order to facilitate the observation of the boron-aluminum interface, a boron filament was introduced in a melt at 1013 K (740 °C) containing different levels of Ti. The Al/B interface was studied using transmission electron microscopy and different phases were identified using the electron diffraction method. The experimental results showed that boron is dissolved in pure aluminum while its dissolution is inhibited in presence of titanium solute. A thin layer of TiB2 formed at the surface of boron thickens with residence time in the melt. The mechanisms by which aluminum is crystallized on boron are discussed. 相似文献
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The production sites of international companies are becoming increasingly interconnected. Due to the uncertainty of multiple factors, determining a location is a strategic choice entailing high financial risk. For this reason, a method for site evaluation was developed allowing multidimensional, i.e., both quantitative and qualitative, uncertainties to be taken into account. The uncertainties are modeled with both probability and fuzzy-set theory and integrated into a modular-structured monetary calculation model. For the analysis and interpretation of evaluation results, methods have been developed which allow risk assessment. The developed method provides a way to handle existing location risks and can thus ensure the success of manufacturing companies in the long term. 相似文献
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Clment De Saint Jores Clment Brandel Najla Gharbi Morgane Sanselme Pascal Cardinael Grard Coquerel 《化学工程与技术》2019,42(7):1500-1504
Since eutomer and distomer show different biological effects, access to pure enantiomers is essential. Preferential enrichment is a relatively new process of chiral resolution developed in the 90s. Extension of its scope was attempted with tryptophan ethyl ester hydrochloride. This salt meets one of the most important requirements for preferential enrichment, namely, a larger solubility for the pure enantiomers with reference to the racemic compound. But, due to the absence of a solid solution, this salt cannot perform preferential enrichment. This impossibility was endorsed by semi‐empirical molecular modeling. 相似文献
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Lake trout (Salvelinus namaycush) reared in hatcheries are exposed to an environment and feeding regime that is different from wild lake trout, and are stocked at substantially larger sizes with higher lipid reserves. In addition to differences in diet and growth, this early experience may alter habitat use compared to the wild cohort. We used seasonal data on the depth and temperature distribution of wild and stocked juvenile lake trout to test for differences in habitat use and inform sampling strategies to evaluate annual recruitment. Bottom trawling was conducted from 2015 to 2019 in the central basin of Lake Champlain every two to four weeks during the ice-free season. Differences in distribution of wild and stocked lake trout were most pronounced during thermal stratification, when wild juveniles were more abundant than stocked juveniles at shallower depths and warmer temperatures and stocked juveniles were more abundant at deeper depths and colder temperatures. Temperature preferences may be a consequence of different early rearing environments; wild lake trout are acclimated to lake temperatures and forage, whereas stocked fish entered the lake with high lipid content and little foraging experience. Unbiased assessment of the proportion of wild lake trout and growth and survival of the entire juvenile lake trout population using bottom trawl sampling should either take place in the pre- and post-stratification seasons when wild and stocked fish are at the same depths, or include the full range of depths and temperatures that wild and stocked fish occupy during the stratified period. 相似文献
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Adem Gharsallaoui Nadia Oulahal Catherine Joly Pascal Degraeve 《Critical reviews in food science and nutrition》2016,56(8):1262-1274
Nisin is a natural preservative for many food products. This bacteriocin is mainly used in dairy and meat products. Nisin inhibits pathogenic food borne bacteria such as Listeria monocytogenes and many other Gram-positive food spoilage microorganisms. Nisin can be used alone or in combination with other preservatives or also with several physical treatments. This paper reviews physicochemical and biological properties of nisin, the main factors affecting its antimicrobial effectiveness, and its food applications as an additive directly incorporated into food matrices. 相似文献