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481.
482.
Anna Aksamit Tahir Choulli Jun Deng Monique Jeanblanc 《Stochastic Processes and their Applications》2019,129(9):3080-3115
This paper completes the studies undertaken in Aksamit et al. (2017, 2018) [[1], [2]] and Choulli and Deng (2017) [[8]], where we quantify the impact of a random time on the no-unbounded-profit-with-bounded-risk concept (called NUPBR hereafter) for quasi-left-continuous models and discrete-time market models respectively. Herein, we focus on NUPBR for semimartingale models that live on thin predictable sets only and when the extra information about the random time is added progressively over time. This leads to the probabilistic setting of two filtrations where one filtration contains the other and makes the random time a stopping time. For this framework, we explain how far NUPBR is affected when one stops the model by an arbitrary random time, or when one incorporates in a progressive way an honest time into the model. Furthermore, we show how to construct explicitly some local martingale deflators in the largest filtration for a particular class of models. As a consequence, by combining the current results on the thin case and those of Aksamit et al. (2017, 2018) [[1], [2]], we elaborate universal results for general semimartingale models. 相似文献
483.
Flavone C-glycosides from Viola yedoensis MAKINO 总被引:4,自引:0,他引:4
A new flavone C-glycoside, apigenin 6-C-alpha-L-arabinopyranosyl-8-C-beta-L-arabinopyranoside, has been isolated from Viola yedoensis together with the known compounds, apigenin 6,8-di-C-alpha-L-arabinopyranoside, apigenin 6-C-alpha-L-arabinopyranosyl-8-C-beta-D-glucopyranoside (isoschaftoside), apigenin 6-C-beta-D-glucopyranosyl-8-C-alpha-L-arabinopyranoside (schaftoside), apigenin 6-C-beta-D-glucopyranosyl-8-C-beta-L-arabinopyranoside (neoschaftoside), apigenin 6,8-di-C-beta-D-glucopyranoside (vicenin-2), apigenin 6-C-alpha-L-arabinopyranosyl-8-C-beta-D-xylopyranoside, apigenin 6-C-beta-D-xylopyranosyl-8-C-alpha-L-arabinopyranoside, luteolin 6-C-beta-D-glucopyranoside (isoorientin) and luteolin 6-C-alpha-L-arabinopyranosyl-8-C-beta-D-glucopyranoside (isocarlinoside). The structures were determined by spectroscopic methods and new or revised (1)H- and (13)C-NMR spectral assignments are proposed for some compounds. 相似文献
484.
485.
Bert Vanhaecht Marcel N. Teerenstra Davy R. Suwier Rudolph Willem Monique Biesemans Cor E. Koning 《Journal of polymer science. Part A, Polymer chemistry》2001,39(6):833-840
A series of copolyamides 12.y was synthesized either with y = 6, or 1,4‐cyclohexanedicarboxylic acid (1,4‐CHDA) residue, or a mixture of both. The influence of the synthetic route of 1,4‐CHDA containing polyamides on the obtained cis–trans ratio of the incorporated 1,4‐CHDA was investigated. The use of acid chlorides provided a synthetic route with full control of the cis–trans ratio of the 1,4‐CHDA residue during synthesis, whereas synthesis at elevated pressure and temperature caused isomerization. The content and cis–trans ratio of 1,4‐CHDA in the copolyamides were determined by solution 13C NMR spectroscopy. Increasing the degree of partial substitution of the adipic acid by 1,4‐CHDA resulted in an increase in Tm, even for low molar precentages of 1,4‐CHDA. This phenomenon points to isomorphous crystallization of both the 12.6 and 12.CHDA repeating units. The mps of the synthesized polyamides were independent of the initial cis–trans ratio of 1,4‐CHDA, provided that the samples were annealed at 300 °C before DSC analysis. The polyamides exhibited a different melting pattern depending on the 1,4‐CHDA content. At a low a 1,4‐CHDA content a net exothermic recrystallization occurred during melting, whereas at higher contents of 1,4‐CHDA this recrystallization occurs to a lesser extent, and two separate melting areas are observed. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 833–840, 2001 相似文献
486.
Rudolph Willem Hassan Dalil Monique Biesemans Jos C. Martins Marcel Gielen 《应用有机金属化学》1999,13(8):605-608
The reaction of hexafluoro‐2,2‐bis(4‐carboxyphenyl)propane with tetrabutyldipropoxydistannoxane, formed in situ from dibutyltin oxide and n‐propanol in benzene, yields a compound the structure of which is a strained macrocycle with a single dicarboxylate moiety. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
487.
Because the dipole moment of its zwitterionic side group is very high (μ∼23 D), poly[3-(N,N-diethyl-N-(5-methacryloyoxy-3-oxopentyl)-ammonio) propanesulfonate] affords a unique polar host matrix possessing a strong solvation power towards a variety of polar or ionic guest species. Water, glycerol, liquid ethylammonium nitrate, triethylammoniopropanesulfonate are all good plasticizers with a fairly similar efficiency of ΔTg∼−2°C/mol% of additive, while a dizwitterion behaves as a weak antiplasticizer. The stoichiometric blends of the polyzwitterion with alkali metal salts of low enough lattice energy such as thiocyanates, trifuoromethanesulfonates, iodides, perchlorates, tetrafluoro or tetraphenylborates, are amorphous systems showing a single glass transition, with plasticization or antiplasticization effects depending on the salt nature. Microphase separation systematically occurs in these binary systems but long-range order is observed only in some cases, with development of lamellar (I−) or hexagonal (SCN−) structures. Conductivity increases and the dielectric constant of the material decreases as salt is added. The activation energies of the conductivity are not strongly affected either by the state of the material, glassy or viscoelastic, or by the salt nature. © 1997 John Wiley & Sons, Ltd. 相似文献
488.
A thermally induced conformational change of zwitterionic groups of two polymers has been observed by thermally stimulated depolarization currents. Different dipole moments of the two conformations is a prerequisite. The appearance of peaks of opposite sign confirms the process. Giant dielectric constants can be obtained at room temperature using high-temperature poling and rapid cooling. 相似文献
489.
490.
Laurent Spina Monique Tillard Claude Belin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(2):i9-i10
The title compound, lithium aluminium silicide (15/3/6), crystallizes in the hexagonal centrosymmetric space group P63/m. The three‐dimensional structure of this ternary compound may be depicted as two interpenetrating lattices, namely a graphite‐like Li3Al3Si6 layer and a distorted diamond‐like lithium lattice. As is commonly found for LiAl alloys, the Li and Al atoms are found to share some crystallographic sites. The diamond‐like lattice is built up of Li cations, and the graphite‐like anionic layer is composed of Si, Al and Li atoms in which Si and Al are covalently bonded [Si—Al = 2.4672 (4) Å]. 相似文献