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排序方式: 共有953条查询结果,搜索用时 185 毫秒
51.
Analysis of target volatile compounds related to fishy off‐flavor in heated rapeseed oil: A comparative study of different headspace techniques 下载免费PDF全文
52.
Alexis Prieto Mlissa Landart Olivier Baudoin Nuno Monteiro Didier Bouyssi 《Advanced Synthesis \u0026amp; Catalysis》2015,357(13):2939-2943
The copper‐catalyzed C(sp2) H trifluoromethylation of N,N‐disubstituted hydrazones using the Togni reagent is demonstrated to proceed efficiently for aliphatic aldehyde‐derived substrates. The success of the reactions relied on the choice of the N,N‐diphenylamino group as the terminal hydrazone amino group where N,N‐dialkylamino groups were preferred for (hetero)aromatic aldehyde‐derived substrates. In addition, the trifluoromethylated N‐arylhydrazones are shown to be ideal substrates for Fischer indole synthesis allowing a straightforward, three‐step access to 2‐trifluoromethylindole derivatives from simple aldehydes.
53.
Florence Barbé Olivia Ménard Yann Le Gouar Caroline Buffière Marie-Hélène Famelart Béatrice Laroche Steven Le Feunteun Didier Dupont Didier Rémond 《Food chemistry》2013,136(3-4):1203-1212
This study aimed to determine the kinetics of milk protein digestion and amino acid absorption after ingestion of four dairy matrices by six minipigs: unheated or heated skim milk and corresponding rennet gels. Digestive contents and plasma samples were collected over a 7 h-period after meal ingestion. Gelation of milk slowed down the outflow of the meal from the stomach and the subsequent absorption of amino acids, and decreased their bioavailability in peripheral blood. The gelled rennet matrices also led to low levels of milk proteins at the duodenum. Caseins and β-lactoglobulin, respectively, were sensitive and resistant to hydrolysis in the stomach with the unheated matrices, but showed similar digestion with the heated matrices, with a heat-induced susceptibility to hydrolysis for β-lactoglobulin. These results suggest a significant influence of the meal microstructure (resulting from heat treatment) and macrostructure (resulting from gelation process) on the different steps of milk proteins digestion. 相似文献
54.
55.
Liyuan Liang Jaime Ruiz Didier Astruc 《Journal of Inorganic and Organometallic Polymers and Materials》2010,20(3):503-510
Alkyne protection by complexation of ethynylferrocene with dicobalt octacarbonyl followed by regioselective acetylation, then deprotection and “click” reaction with a nona-azido-terminated arene-cored dendrimer leads to the heterodifunctional nona(1,2,3-triazolyl-acetylferrocenyl) dendrimer. Cyclic voltammetry of this metallodendrimer shows recognition of both ATP2? and Pd2+. HAuCl4 is reduced much more slowly to gold nanoparticles by the nona(triazolyl-acetylferrocenyl dendrimer than by the nona(triazolylferrocenyl) dendrimer due to the shift of redox potential in the new heterodifunctional dendrimer compared to that of the parent ferrocenyl dendrimer. 相似文献
56.
Fabrice Rigaud Jean-Michel Portal Didier Nee Fabrice Argoud 《Microelectronics Reliability》2011,51(6):1136-1141
The objective of this paper is to present a mixed test structure designed to characterize yield losses due to hard defect and back-end process variation (PV) at die and wafer level. A brief overview of the structure, designed using a ST-Microelectronics’ 130 nm technology, is given. This structure is based on a SRAM memory array for detecting hard defects. Moreover each memory cell can be configured in the Ring Oscillator (RO) mode for back-end PV characterization. The structure is tested in both modes (SRAM, RO) using a single test flow. The test data analysis method is presented and applied to experimental results to confirm the ability of the structure to monitor PV and defect density. 相似文献
57.
Olivier Pras Davide Beneventi Didier Chaussy Paul Piette Sandra Tapin-Lingua 《Journal of Materials Science》2013,48(20):6911-6920
In this study, microfibrillated cellulose (MFC) and dendritic copper were used as binder and conductive phase for the elaboration of self-standing conductive films and coatings. A filtration technique was used to prepare MFC/Cu films from particle dispersions in water and ethanol. In aqueous slurries copper oxidized and an additional corona treatment or the use of zinc particles as sacrificial anode were necessary to obtain films with conductivities ranging from 70 to 2500 S m?1, respectively. In ethanol-based MFC/Cu slurries, copper was subjected to limited oxidation. However, the low packing density of conductive particles (below the percolation threshold) led to resistive films which, after densification by calendering, displayed extremely high conductivities, up to 70000 S m?1. Aqueous MFC/Cu slurries were successfully used for the deposition of conductive coatings on copy paper by Mayer rod coating and screen printing, which were subsequently treated by corona discharge and calendering. The obtained coatings displayed intermediate conductivity (i.e. 95 and 570 S m?1 for rod coating and screen printing, respectively), which can be further increased using zinc particles or ethanol-based formulations. 相似文献
58.
Virginie Dulong Renauld Forbice Eric Condamine Didier Le Cerf Luc Picton 《Polymer Bulletin》2011,67(3):455-466
Rheological and swelling properties of hydrogels based on pullulan crosslinked with sodium trimetaphosphate (STMP) are explained
according to various polymer and crosslinking agent concentrations using 31P-nuclear magnetic resonance study. This method has allowed determining the amount of all the species present in the medium
when varying both pullulan and STMP concentrations. We have clearly demonstrated with a good agreement by both 31P-NMR and rheology that a critical STMP concentration occurs which is function of pullulan concentration. This typical crosslinking
agent concentration delimitates the maximum of gel structure together with the minimum of swelling. 相似文献
59.
Beach Mark Bourse Didier Dillinger Markus Falk Rainer Farnham Tim Navarro-Prieto Raquel Wiebke Thomas 《电信纪事》2002,57(7-8):653-676
To date, research into reconfigurable mobile communications has predominantly focussed on the software radio concept, and specifically on the hardware technologies required to move physical layer processing into a programmable environment [1, 2, 3]. Although an interesting and necessary challenge, this only represents a fraction of the overall support and technology required to realise the potential of the concept. Other necessary developments include network/terminal cooperation for seamless inter-standard handoff, QoS management for software download and reconfiguration, a secure software download mechanism, terminal software and mobile radio network architecture supporting terminal reconfiguration, management for software downloads, configuration management, capability negotiation, radio resource management and spectrum allocation policies etc… This paper describes results from the EuropeanIst Trust (Transparently Reconfigurable UbiquitouS Terminal) [4] project concerning user and operator requirements, the proposed overall system environment, security issues, concerted radio resource management, and expected time frame for the development of reconfigurable terminals. 相似文献
60.
Didier Dubois Hélène Fargier Jérôme Fortin 《Journal of Intelligent Manufacturing》2005,16(4-5):407-421
In project management, three quantities are often used by project managers: the earliest starting date, the latest starting date and the float of tasks. These quantities are computed by the Program Evaluation and Review Techniques/Critical Path Method (PERT/CPM) algorithm. When task durations are ill known, as is often the case at the beginning of a project, they can be modeled by means of intervals, representing the possible values of these task durations. With such a representation, the earliest starting dates, the latest starting dates and the floats are also intervals. The purpose of this paper is to give efficient algorithms for their computation. After recalling the classical PERT/CPM problem, we present several properties of the concerned quantities in the interval-valued case, showing that the standard criticality analysis collapses. We propose an efficient algorithm based on path enumeration to compute optimal intervals for latest starting times and floats in the general case, and a simpler polynomial algorithm in the case of series-parallel activity networks. 相似文献