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排序方式: 共有2219条查询结果,搜索用时 31 毫秒
71.
Saint Martin Marie-Judith Orlhac Fanny Akl Pia Khalid Fahad Nioche Christophe Buvat Irène Malhaire Caroline Frouin Frédérique 《Magma (New York, N.Y.)》2021,34(3):355-366
Magnetic Resonance Materials in Physics, Biology and Medicine - Quantitative analysis in MRI is challenging due to variabilities in intensity distributions across patients, acquisitions and... 相似文献
72.
73.
Fabrice Roussière Christophe Baley Grégory Godard Dominique Burr 《Applied Composite Materials》2012,19(2):171-188
Nowadays, the ecological footprint of a material is becoming tremendously important. The Poly l-Lactide Acid (PLLA) matrix
composites reinforced by randomly scattered flax fibres have mechanical properties similar to polyester/glass composites [1], lower environmental impacts and can be compost at the end of their lives. In this study, the mechanical characterization
of biocomposites has been pushed further with the determination of the compressive and tensile properties. Furthermore, the
mechanical properties of single flax fibres have been measured and implemented in a micro-mechanical estimation of the composite
elastic modulus. Tensile and compressive stiffness determined by the mechanical analyses show very good correlations with
the mathematical estimation. 相似文献
74.
Marvin Ricaurte Jean-Philippe TorréJoseph Diaz Christophe Dicharry 《Chemical Engineering Research and Design》2014
This paper investigates an original method to efficiently trigger gas hydrate crystallization. This method consists of an in situ injection of a small amount of THF into an aqueous phase in contact with a gas-hydrate-former phase at pressure and temperature conditions inside the hydrate metastable zone. In the presence of a CO2–CH4 gas mixture, our results show that the THF injection induces immediate crystallization of a first hydrate containing THF. This triggers the formation of the CO2–CH4 binary hydrate as proven by the pressure and temperature reached at equilibrium. This experimental method, which “cancels out” the stochasticity of the hydrate crystallization, was used to evaluate the effect of the anionic surfactant SDS at different concentrations, on the formation kinetics of the CO2–CH4 hydrate. The results are discussed and compared with those published in a recent article (Ricaurte et al., 2013), where THF was not injected but present in the aqueous phase from the beginning and at much higher concentrations. 相似文献
75.
Innovation-based strategies are widely recognized as key drivers to maintain competitive advantage. The design and strategic literature underline the possibility of triggering a multiproduct value-expansion dynamic based on the creation of new concepts dynamically twinned with corporate strategy. However, the multiproject-management literature—portfolio, program, and platform—lags behind and remains focused on ex ante coordination, resource allocation and selectionism. Thus, there are still few indications of the processes that stimulate and orient continuous, profitable multiproject creative expansion. Bridging the multiproject-management literature and design theory, we propose a model of multiproject lineage management (MPLM), which focuses on the key processes that drive exploration efforts and shape innovation trajectory. We conduct a multiple longitudinal case analysis in the automobile sector. Based on this analysis, we expose the principles of MPLM, mapping the roles of corporate, program and project management within a global expansion project. Finally, we highlight our contributions to managerial practices and the related literature. 相似文献
76.
Deborah Houssin-Agbomson Didier Jamois Christophe Proust Jérôme Daubech Sidonie Ruban Simon Jallais 《International Journal of Hydrogen Energy》2012
In order to improve risk analyses and influence the design of the future H2 systems, an experimental study on “real” leaks qualification and quantification was performed. In H2 energy applications, fittings appeared as a significant leakage potential and subsequently explosion and flame hazards. Thus, as a part of the “Horizon Hydrogène Energie” French program, four kinds of commercial fittings usually employed on H2 systems were tested thanks to a new high pressure test bench – designed, setup and operated by INERIS – allowing experiments to be led for H2 pressures until 700 bar. The fittings underwent defined stresses representative of H2 systems lifetime and beyond. The associated leaks – when existing – are characterized in terms of flow rate. 相似文献
77.
78.
Marie Hurtgen Antoine Debuigne Didier Gigmes Christine Jérôme Christophe Detrembleur 《Polymer》2012,53(20):4353-4358
The grafting mechanism of poly(vinyl acetate) macroradicals prepared by cobalt-mediated radical polymerization onto C60 is investigated. The experimental conditions directly impact the nature and stability of the PVAc/C60 adducts. In the presence of residual initiating radicals that can compete with PVAc° macroradicals for addition onto C60, mixtures of PVAc/C60 adducts having between one and eight polymer chains per C60 are formed. PVAc/C60 adducts prepared with low [PVAc]:[C60] ratios may contain weak C60–C60 bonds that further dissociate and account for the instability of the products. The formation of such dimers can be lessened by increasing the temperature from 30 °C to 100 °C. The temperature increase also allows a complete dissociation of the PVAc-Co dormant species into PVAc° macroradicals and an almost quantitative grafting of eight PVAc chains onto C60, leading to well-defined C60(PVAc)8 octa-adducts. These results might shed new light on the grafting onto C60 of macroradicals prepared by other CRP techniques. 相似文献
79.
Antoine Le Duigou Jean-Marc Deux Peter Davies Christophe Baley 《Applied Composite Materials》2012,19(3-4):363-378
In the present paper the environmental impact of biocomposites and bio-sandwich materials production are evaluated, using simplified Life Cycle Analysis (LCA) following the procedure recommended in the ISO 14044 standard. The materials are dimensioned and evaluated by comparing with reference materials, glass mat reinforced unsatured polyester and glass mat/unsatured polyester/balsa sandwich. The results indicate that bio-sandwich materials are very attractive in terms environmental impact. However further improvements in biocomposite and bio-sandwich mechanical strength are necessary if they are to be used in transport application compared to glass/polyester and glass/polyester/balsa sandwich. 相似文献
80.
A priori checking inconsistencies among strategic constraints for assembly plan generation 总被引:1,自引:1,他引:0
Christophe Perrard Eric Bonjour 《The International Journal of Advanced Manufacturing Technology》2012,63(5-8):817-838
This paper is related to the field of assembly plan generation. It describes a new approach to a priori check the consistency of an assembly strategy that is given by the assembly system designers before running an assembly plan generation algorithm. The aim of this work is to improve the assembly plan designer’s efficiency by reducing the research space while proving the existence of acceptable solutions. The assembly strategy combined with the product’s model implies a set of constraints on the assembly processes. The proposed method determines whether the given assembly strategy produces possible assembly processes. In case of inconsistencies among the strategic constraints, the method will help the designer to identify the contradictory constraints. The set of constraints can be expressed by a Boolean equation. First we present the key concepts and models related to the product, processes, and added values in the field of assembly plan generation. Second we define existing strategic constraints, and propose three new ones and a classification of strategic assembly constraints. The originality of the proposed method consists in defining an elementary strategic constraint that is used to describe every other constraint. The proposed method leads to model an assembly strategy by a single Boolean equation that is used to check the inconsistencies. An industrial case study is provided to highlight and to demonstrate the interests of this approach. 相似文献