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201.
202.
Branislav Musicki Anne-Marie Periers Laurent Piombo Patrick Laurin Michel Klich Claudine Dupuis-Hamelin Patrice Lassaigne Alain Bonnefoy 《Tetrahedron letters》2003,44(52):9259-9262
The design, synthesis, and biological activity in vitro of modified coumarin inhibitors of gyrase B are presented. Noviose, the sugar portion of coumarin antibiotics, was replaced by simplified mimics, a 5′,5′-dimethylcyclohexane or piperidine. 相似文献
203.
We provide an explicit Plancherel formula for the p-adic group GL(n). We determine explicitly the Bernstein decomposition of Plancherel measure, including all numerical constants. We also prove a transfer-of-measure formula for GL(n). To cite this article: A.-M. Aubert, R. Plymen, C. R. Acad. Sci. Paris, Ser. I 338 (2004). 相似文献
204.
Artem Zibarov Abdelouahd Oukhrib Julien Aujard Catot Cdric-Olivier Turrin Anne-Marie Caminade 《Molecules (Basel, Switzerland)》2021,26(13)
AB5 compounds issued from the reactivity of hexachlorocyclotriphosphazene are relatively easy to obtain using two ways: either first the reaction of one chloride with one reagent, followed by the reaction of the five remaining Cl with another reagent, or first the reaction of five chlorides with one reagent, followed by the reaction of the single remaining Cl with another reagent. This particular property led to the use of such compounds as core for the synthesis of dendrons (dendritic wedges), using the five functions for growing the dendritic branches. The single function can be used for the synthesis of diverse types of dendrimers (onion peel, dumbbell-shape, Janus), for covalent or non-covalent grafting to solid surfaces, providing nanomaterials, for grafting a fluorophore, especially for studying biological mechanisms, or for self-associations to get micelles. All these properties are reviewed in this paper. 相似文献
205.
The shape and the surface charge of microchannels are critical parameters for ionic and mass transport in microfluidic systems. A great number of studies and developments have been carried out in order to optimize these features separately. We propose to consider them together within a new fundamental parameter for microfluidics, that we named the Volumic Surface Charge (VSC), which is the ratio of the surface charge to the section height in planar microchannels. The non-linear effects induced by rapid VSC variations can result in selective preconcentration processes, which can be used for a simultaneous preconcentration and separation of biomolecules within simple straight channels. In this review, we first present 3 different techniques that we developed to tune the VSC either by surface chemical patterning, integration of polarisable interfaces or geometrical constrictions. The proof of concept of the selective preconcentration using VSC variations will be presented on the basis of experimental results obtained with fluorescent probes and numerical simulations. 相似文献
206.
Identification and quantitative determination of individual components of resin collected on the trunk of 28 Cedrus atlantica trees, grown in Corsica, has been carried out using 13C NMR spectroscopy. Eight resin acids bearing either the pimarane or abietane skeleton, two monoterpene hydrocarbons and four oxygenated neutral diterpenes have been identified, as well as three lignans, scarcely found in resins. Three groups could be distinguished within the 28 resin samples. The nine samples of Group I had their composition dominated by diterpene acids (33.7-45.8%), with abietic acid (6.2-18.7%) and isopimaric acid (5.1-12.6%) being the major components. The four samples of Group II contained resin acids (main components) and lignans in moderate amounts (up to 10.3%). Conversely, lignans (38.8-63.8%) were by far the major components of the 15 samples of Group III. Depending on the sample, the major component was pinoresinol (18.1-38.9%), lariciresinol (17.2-33.7%) or lariciresinol 9'-acetate (16.9-29.1%). Finally, due to the high biological interest in lignans, a rapid procedure, based on 1H NMR spectroscopy, was developed for quantification of lignans in resins of C. atlantica. 相似文献
207.
Arnaud De Luca Karine Bernardo Marine Frasquet-Darrieux Patricia Christin Anne-Marie Schiphorst Mathilde Grand 《Isotopes in environmental and health studies》2013,49(4):385-393
ABSTRACTObesity increases protein metabolism with a potential effect on nitrogen isotope fractionation. The aim of this study was to test the influence of obesity on human milk extracted protein 15N natural isotope abundance (NIA) at one month post-partum and to compare human milk extracted protein 15N NIA and bulk infant hair 15N NIA. This cross-sectional observational study involved 16 obese mothers (body mass index (BMI)?≥?30?kg?m?2 before pregnancy) matched with 16 normal-weight mothers (18.5?kg?m?2?≤?BMI?<?25?kg?m?2) for age and pregnancy characteristics. Human milk extracted protein and bulk infant hair 15N NIA were determined by isotope ratio monitoring by mass spectrometry interfaced to an elemental analyser (IRM-EA/MS). No significant difference was found in human milk protein 15N NIA values between obese and normal-weight mothers (8.93?±?0.48?‰ vs. 8.95?±?0.27?‰). However, human milk protein 15N NIA was significantly lower than bulk infant hair 15N NIA: 8.94?±?0.38?‰ vs. 9.66?±?0.69?‰, respectively. On the basis of these results, it is concluded that human milk protein 15N NIA measured at one month post-partum is not influenced by maternal obesity. These findings suggest that 15N NIA may be exploited to study metabolism without considering maternal obesity as a confounder. 相似文献
208.
Robert Faure Abdallah Mahamoud Jean-Pierre Galy Emile-Jean Vincent Anne-Marie Galy Jacques Barbe 《光谱学快报》2013,46(3):223-238
13C-NMR spectra of several 9-acridanones with different substituents both on the ring (R1 = CH3, OCH3, NH2, N(CH3)2, NO2) and at the nitrogen atom (R2 = H, CH3 C2H5, CH2-C6H5, C[tbnd]C-CH3, (CH2)2N(C2H2)2, CH=C=CH2) have been recorded. The C-NMR chemical shifts are discussed as a function of the nature of the substituent, the importance of peri steric interactions and the electronic structure of the acridanone ring. There is a good linear relationship between the total electronic density and the chemical shifts. 相似文献
209.
210.
Matthew J. Coady Nuwansiri N. K. Getangama Aria Khalili Michael Wood Kent E. Nielsen John R. de Bruyn Jeffrey L. Hutter Robert J. Klassen Anne-Marie Kietzig Paul J. Ragogna 《Journal of polymer science. Part A, Polymer chemistry》2020,58(7):1022-1029
Preventing ice growth on infrastructure, vehicles, and appliances remains a significant engineering challenge. Damage caused by ice growth on these installations can be expensive to repair, and their failure can be dangerous. Materials such as cross-linked polymer networks make effective anti-ice coatings and can prevent ice growth: reducing the cost of infrastructure repairs and limiting downtime. A link between cross-link density and ice adhesion has been demonstrated, such that lower cross-link density materials tend toward lower ice adhesion. Here we describe a method of lowering cross-link density by incorporating the covalently bound comonomers methyl methacrylate, lauryl methacrylate, and styrene into UV-cured PDMS-based polymer networks. Cross-link density, hardness, surface roughness, and ice adhesion on these materials are tested, showing the influence of comonomer proportions on their properties. Durability is found to increase with the addition of 5, 10, and 25 wt% comonomer, with little to no effect on ice adhesion until 25 wt%, where increases in ice adhesion are observed. Coatings show promisingly low ice adhesion of ~50 kPa, maintaining this low adhesion for up to 50 deicing cycles. 相似文献