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91.
Michel Gratton Camille Gontier Saïd Rja Fi Allah Abdelhake Bouchou Didier Picart 《European Journal of Mechanics - A/Solids》2009,28(5):935-947
The present paper deals with the characterisation of the static mechanical behaviour of an energetic material all along its lifespan. The material behaviour is viscoplastic, damageable and sensitive to hydrostatic pressure. For such materials, existing models have generally been developed in the framework of transient dynamic behaviour. These models are not suitable for a static study. Therefore a specific experimental protocol and an associated model are developed. Characterisation is derived from both uniaxial compressive, tensile tests and triaxial tests. Plastic behaviour is described by means of a parabolic yield criterion and a new hardening law. Non-associated plastic flow rule and isotropic damage complete the model. The performance of the model is illustrated through the simulation of various loading paths. 相似文献
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Vardan Martikyan Camille Beluffi Steffen J. Glaser Marc-Andr Delsuc Dominique Sugny 《Molecules (Basel, Switzerland)》2021,26(10)
We study the application of Optimal Control Theory to Ion Cyclotron Resonance. We test the validity and the efficiency of this approach for the robust excitation of an ensemble of ions with a wide range of cyclotron frequencies. Optimal analytical solutions are derived in the case without any pulse constraint. A gradient-based numerical optimization algorithm is proposed to take into account limitation in the control intensity. The efficiency of optimal pulses is investigated as a function of control time, maximum amplitude and range of excited frequencies. A comparison with adiabatic and SWIFT pulses is done. On the basis of recent results in Nuclear Magnetic Resonance, this study highlights the potential usefulness of optimal control in Ion Cyclotron Resonance. 相似文献
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Total Syntheses and In Vivo Quantitation of Novel Neurofuran and Dihomo‐isofuran Derived from Docosahexaenoic Acid and Adrenic Acid 下载免费PDF全文
Aurélien de la Torre Yiu Yiu Lee Attilio Mazzoni Dr. Alexandre Guy Dr. Valérie Bultel‐Poncé Dr. Thierry Durand Dr. Camille Oger Dr. Jetty Chung‐Yung Lee Dr. Jean‐Marie Galano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2442-2446
Neurofurans (NeuroFs) and dihomo‐isofurans (dihomo‐IsoFs) are produced in vivo by non‐enzymatic free‐radical pathways from docosahexaenoic and adrenic acids, respectively. As these metabolites are produced in minute amounts, their analyses in biological samples remain challenging. Syntheses of neurofuran and dihomo‐isofurans described are based on a pivotal strategy, thanks to an enantiomerically enriched intermediate, which allowed, for the first time, access to both families: the alkenyl and enediol. Owing to this formation, quantitation of specific NeuroF and dihomo‐IsoFs in biological samples was attainable. 相似文献
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