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291.
In this paper, the non-local density functional theory is used in combination with SAFT-VR, to investigate the pore pressure behaviour of water confined in various nanopores. Due to the efficiency and low computational cost of the method, many configurations and thermodynamic conditions are explored. In particular, capillary condensation and evaporation of water, their impact on the pore pressure, and the effect of surface activation are evaluated. Successive first-order phase transitions of ultra-confined water monolayer are also highlighted.  相似文献   
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Grapevine is susceptible to fungal diseases generally controlled by numerous chemical fungicides. Elicitors of plant defence are a way of reducing the use of these chemicals, but still provide inconsistent efficiency. Easy-to-analyse markers of grapevine responses to elicitors are needed to determine the best conditions for their efficiency and position them in protection strategies. We previously reported that the elicitor sulphated laminarin induced the emission of volatile organic compounds (VOCs) by grapevine leaves. The present study was conducted to characterise and compare VOC emissions in response to other elicitors. Bastid® was first used to test the conditions of VOC collection and analysis. Using SBSE-GC-MS, we detected several VOCs, including the sesquiterpene α-farnesene, in a time-dependent manner. This was correlated with the induction of farnesene synthase gene expression, in parallel with stilbene synthesis (another defence response), and associated to resistance against downy mildew. The other elicitors (Redeli®, Romeo®, Bion®, chitosan, and an oligogalacturonide) induced VOC emission, but with qualitative and quantitative differences. VOC emission thus constitutes a response of grapevine to elicitors of various chemical structures. Therefore, VOC analysis is relevant for studying the impact of environmental factors on grapevine defence responses and optimising the performance of elicitors in vineyards.  相似文献   
296.
An analogue of the paclitaxel-like antimicrotubule agent laulimalide with a phenyl in place of the dihydropyran has been synthesized. The fragments C1-C14 and C15-C28 were coupled via a stereoselective intermolecular allylboration. Ring closure was achieved using Yamaguchi’s protocol.  相似文献   
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Well‐defined macromonomers of poly(ethylene oxide) and poly(tert‐butyl methacrylate) were obtained by anionic polymerization induced directly by the carbanion issued from 2‐methyl‐2‐oxazoline. When ethylene oxide was added to this carbanion with lithium as the counterion, a new compound able to initiate the polymerization of ε‐caprolactone in an anionically coordinated way was synthesized, and this led to well‐defined poly(ε‐caprolactone) macromonomers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2440–2447, 2005  相似文献   
298.
We give examples of bounded domains Ω, even contractible, having the following property: there exists k?(Ω) such that, for every integer k?k?(Ω), problem P(ε,Ω) below, for ε>0 small enough, has at least one solution blowing up as ε→0 at exactly k points. We also prove that the blow-up points tend to some points of as k→∞. To cite this article: R. Molle, D. Passaseo, C. R. Acad. Sci. Paris, Ser. I 335 (2002) 459–462.  相似文献   
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Mixtures of TEOS with substituted methoxysilanes generate low-density xerogels due to a nucleation mechanism involving the substituted alkoxysilane. The sol–gel transition of these mixtures was followed by rheological characterisation. The transition from sol to gel takes place in a few minutes at ambient temperature. For the series exhibiting nucleation by the additive, the gel time goes through a slight minimum when the ratio of additive/main reagent increases. The elastic modulus increases with increasing ratio of additive/main reagent as the particle size decreases because of the nucleation mechanism by the additive. Samples with smaller particles exhibit the highest modulus for equal silica concentrations.  相似文献   
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We propose a way to account for inspection errors in a particularframework. We consider a situation where the lifetime of a systemdepends essentially of a particular part. A deterioration ofthis part is regarded as an unacceptable state for the safetyof the system and a major renewal is deemed necessary. Thusthe statistical analysis of the deterioration time distributionof this part is of primary interest for the preventive maintenanceof the system. In this context, we faced the following problem.In the early life of the system, unwarranted renewals of thepart are decided upon, caused by overly cautious behaviour.Such unnecessary renewals make the statistical analysis of deteriorationtime data difficult and can induce and underestimation of themean life of the part. To overcome this difficulty, we proposeto regard the problem as an incomplete data model. We presentits estimation under the maximum likelihood methodology. Numericalexperiments show that this approach eliminates the pessimisticbias in the estimation of the mean life of the part. We alsopresent a Bayesian analysis of the problem which can be usefulin a small sample setting.  相似文献   
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