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61.
Christophe O. Soulage Lucie Grand Alain Géloën Stéphane Chambert 《Tetrahedron letters》2012,53(5):480-483
A straightforward procedure leading to the flavone cirsimaritin and its 4′-O-β-d-glycosylation to afford cirsimarin, its corresponding flavone glucopyranoside, is described. The biological properties of cirsimarin, measured on human adipocytes, showed potent effects on both lipolysis and lipogenesis. Cirsimarin could therefore be considered as an efficient tool in the struggle against excessive adipose tissue deposition and as a potential candidate in the treatment of obesity. 相似文献
62.
63.
Dr. Joachim RosenmÜller 《Probability Theory and Related Fields》1971,17(4):259-308
Ohne ZusammenfassungBesonders bedanken möchte ich mich bei Herrn Prof. K.Jacobs fÜr sein dauerndes Interesse an meinen BemÜhungen. 相似文献
64.
Let (W,H,μ) be an abstract Wiener space, assume that is a second probability measures on such that , with lower bounded and H-convex. Let , be the solution of the Monge problem transporting μ to ν and realizing the H-Wasserstein distance between μ and ν. We prove that hence the Gaussian Jacobian is well-defined and T is the strong solution of the Monge–Ampère equation ΛL°T=1 a.s. on W. To cite this article: D. Feyel, A.S. Üstünel, C. R. Acad. Sci. Paris, Ser. I 339 (2004). 相似文献
65.
A direct kinetic study is reported for the electrophilic amination of substituted phenylmagnesium bromides with N,N‐dimethyl O‐(mesitylenesulfonyl)hydroxylamine in THF. Rate data, Hammett relationship, and activation entropy are consistent with a SN2 displacement involving the attack of carbanions to sp3N in the amination reagent (AR). Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
66.
O. Üzengi Aktürk E. Aktürk M. Tomak 《International Journal of Theoretical Physics》2008,47(12):3310-3320
In this paper, we focus on Sobolev inequality in the context of Sharma-Mittal entropy. Using this new inequality, generalized entropic uncertainty relation in accordance with Sharma-Mittal entropy is derived and the pseudoadditivity relation has been obtained. This new entropic uncertainty relation has then been applied to physical examples such as one dimensional harmonic oscillator and Pösch-Teller potential. Finally, it has been shown that for certain values of the parameters of Sharma-Mittal measure, the present results reduce to the corresponding results of Shannon, Renyi and Tsallis measures. 相似文献
67.
Assuming that a dynamical system (DS) has a periodic solutionwith period T in the neighborhood of an equilibrium, a newDS can be obtained which governs approximately the motion oftrajectories in the neighborhood of the periodic orbit. Approximatesymmetries and first integrals have been discussed for this DS. Theresults have been demonstrated on the Helmholtz oscillator. 相似文献
68.
Journal of Solid State Electrochemistry - 相似文献
69.
Ümit Akbey Robert Graf Yuan G. Peng Peter P. Chu Hans W. Spiess 《Journal of Polymer Science.Polymer Physics》2009,47(2):138-155
NMR studies of the structure and dynamics of a system composed of the acidic polymer poly(acrylic acid) (PAA) and the basic polymer poly(4‐vinyl pyridine) (P4VP) are presented. This system aims at the application of anhydrous proton‐conducting membranes that can be used at elevated temperatures at which the proton conduction of hydrated membranes breaks down. The 1H NMR measurements have been preformed under fast magic angle spinning (MAS) conditions to achieve sufficient resolution and the applied 1H NMR methods vary from simple 1H MAS to double‐quantum filtered methods and two‐dimensional 1H double‐quantum spectroscopy. The dynamic behavior of the systems has been investigated via variable temperature 1H MAS NMR. 13C cross‐polarization MAS NMR provides additional aspects of dynamic and structural features to complete the picture. Different types of acidic protons have been identified in the studied PAA‐P4VP systems that are nonhydrogen‐bonded free acidic protons, hydrogen‐bonded dicarboxylic dimers, and protons forming hydrogen bonds between carboxylic protons and ring nitrogens. The conversion of dimer structures in dried PAA to free carboxylic acid groups is accomplished at temperatures above 380 K. However, the stability of hydrogen‐bonding strongly depends on the hydration level of the polymer systems. The effect of hydration becomes less apparent in the complexes. An inverse proportionality between hydrogen‐bonding strength and proton conduction in the PAA‐P4VP acid–base polymer blend systems was established. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 138–155, 2009 相似文献
70.
Combined experimental and computational studies on molecular structure of newly synthesised transtirans 1,2,3-tribromo-1,2,3-trihydro-1H-benz[f]indene (TTTBI) were reported. Also, only computational studies were done for cis-trans-1,2,3-tribromo-1,2,3-trihydro-1H-benz[f]indene (CTTBI) and cis-cis-1,2,3-tribromo-1,2,3-trihydro-1H-benz[f]indene (CCTBI) in order to understand the vibrational spectra and molecular parameters of them. The geometry optimization
and vibrational wave numbers of the title molecules were carried out with the Gaussian98 program package by using Hartree-Fock
(HF) and Density Functional Theory (DFT) with B3LYP functional and 6–31G (d) basis set. All calculations were done for the
title compounds in their ground states. Especially for CTTBI and CCTBI, which could not be synthesized yet, these kind of
pre-calculations take an important role for their synthesis process. Also crystal structural parameters of TTTBI by single-crystal
X-ray diffraction method was used as input for computational study of it. Observed and calculated vibrational wave numbers
were compared. Because the use of benz[f]indene as a cyclopentadienyl ligand attracted much attention because an annulated
benzo ring might increase both the stereocontrol and productivity of catalytic system, TTTBI and other computationally studied
and modeled two molecules may play an important role of other types of compounds as a starting structures. 相似文献