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131.
Moresco F Gross L Alemani M Rieder KH Tang H Gourdon A Joachim C 《Physical review letters》2003,91(3):036601
A crucial problem in molecular electronics is the control of the electronic contact between a molecule and its electrodes. As a model system, we investigated the contact between the molecular wire group of a C90H98 (Lander) molecule and the edge of a Cu(111) monatomic step. The reproducible contact and decontact of the wire was obtained by manipulating the Lander with a low temperature scanning tunneling microscope. The electronic standing wave patterns on the Cu(111) surface serve to monitor the local electronic perturbation caused by the interaction of the wire end with the step edge, giving information on the quality of the contact. 相似文献
132.
Seeber M De Benedetti PG Fanelli F 《Journal of chemical information and computer sciences》2003,43(5):1520-1531
Comparative molecular dynamics simulations of the 5-HT(1A) receptor in its empty as well as agonist- (i.e. active) and antagonist-bound (i.e. nonactive) forms have been carried out. The agonists 5-HT and (R)-8-OH-DPAT as well as the antagonist WAY100635 have been employed. The results of this study strengthen the hypothesis that the receptor portions close to the E/DRY/W motif, with prominence to the cytosolic extensions of helices 3 and 6, are particularly susceptible to undergo structural modification in response to agonist binding. Despite the differences in the structural/dynamics behavior of the two agonists when docked into the 5-HT(1A) receptor, they both exert a destabilization of the intrahelical and interhelical interactions found in the empty and antagonist-bound receptor forms between the arginine of the E/DRY sequence and both D133(3.49) and E340(6.30). For both agonists, the chemical information transfer from the extracellular to the cytosolic domains is mediated by a cluster of aromatic amino acids in helix 6, following the ligand interaction with selected amino acids in the extracellular half of the receptor, such as D116(3.32), S199(5.42), Y195(5.38), and F361(6.51). A significant reduction in the bend at P360(6.50), as compared to the empty and the antagonist-bound receptor forms, is one of the features of the agonist-bound forms that is related to the breakage of the interhelical salt bridge between the E/DRY arginine and E340(6.30). Another structural feature, shared by the agonist-bound receptor forms and not by the empty and antagonist-bound forms, is the detachment of helices 2 and 4, as marked by the movement of W161(4.50) away from helix 2, toward the membrane space. 相似文献
133.
Siraye E. Debebe Desta A. Gedefaw Wendimagegn Mammo Teketel Yohannes Francesca Tinti Alberto Zanelli Valeria Fattori Nadia Camaioni 《Journal of polymer science. Part A, Polymer chemistry》2011,49(12):2693-2699
The synthesis and characterization of a novel polythiophene substituted with a 2′‐pentyloxy‐5′‐(1″′‐oxooctyl) phenyl group (PPOPT) is reported. The bulk transport properties of thin films of PPOPT are investigated by admittance spectroscopy. The dramatic effect of the phenyl side chain on the mobility of positive carriers in films of PPOPT is described. The photophysics of PPOPT in both solution and thin film is also investigated and correlated to substituent‐driven intrachain and interchain arrangements. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
134.
Francesca Cardona Inmaculada Robina Pierre Vogel 《Journal of carbohydrate chemistry》2013,32(4-5):555-571
ABSTRACT Cross-aldolisation of 3,6-[(tert-butoxy)carbonyl]imino-2,3,6-trideoxy-4,5-O-isopropylidene-L-arabino-hexose (10) with 1,6-anhydro-2-O-benzyl-3-deoxy-β-D-erythro-hexopyrano-4-ulose (6) generates, after water elimination, a single enone 11 that is reduced selectively into an allylic alcohol 12, deprotection of which affords methyl (Z)-3-deoxy-3-(1,2,3,6-tetradeoxy-3,6-imino-L-arabino-hexitol-1-C-ylidene)-β-D-xylo-hexofuranoside (1) and (Z)-1,6-anhydro-3-deoxy-3-(1,2,3,6-tetradeoxy-3,6-imino-L-arabino-hexitol-1-C-ylidene)-β-D-xylo-hexopyranose (14). 相似文献
135.
This paper concerns with a state of bending for a linear transversely isotropic plate model based on the Mindlin assumption on the displacement. By using appropriate families of line-integral measures, we are able to establish results about the spatial behaviour of transient and steady-state solutions. All the results are obtained under relaxed hypotheses on the positive definiteness of the elasticity tensor. 相似文献
136.
The paper describes a new space of variable degree polynomials. This space is isomorphic to ℙ6, possesses a Bernstein like basis and has generalized tension properties in the sense that, for limit values of the degrees,
its functions approximate quadratic polynomials. The corresponding space of C
3, variable degree splines is also studied. This spline space can be profitably used in the construction of shape preserving
curves or surfaces.
AMS subject classification (2000) 65D07, 65D17, 65D10 相似文献
137.
Franco Varsano Francesca Decker Enrico Masetti 《Monatshefte für Chemie / Chemical Monthly》2001,132(1):83-95
Summary. Ce-V mixed oxide films have been deposited by RF sputtering with the aim of increasing the Li charge capacity of counter
electrodes in smart windows. Such mixed oxides have shown high transmittance and optical passivity in the visible region.
After electrode pre-conditioning by cyclic voltammetry, a good electrochemical reversibility in LiClO4– propylene carbonate electrolyte was observed, and large Li-charge capacity under galvanostatic charging (up to 50 mCċcm−2) has been measured. The electrode charge capacity decreased after prolonged insertion-deinsertion cycles, whereas the photoptic
transmittance remained about constant. After 800 cycles the Li-charge capacity decreased to 40 mCċcm−2. The Li diffusion coefficient inside the films measured by electrochemical impedance and by galvanostatic titration ranged
from 10−11 cm2ċs−1 to 10−13cm2ċs−1. We observed that the Li charge capacity of the film electrodes is a function of the film deposition conditions, because
it increased with the vanadium oxide concentration in the target and with the oxygen content in the sputtering atmosphere.
Received June 23, 2000. Accepted (revised) August 7, 2000 相似文献
138.
139.
Francesca Aicardi 《Functional Analysis and Other Mathematics》2008,2(1):1-13
We prove the propositions stated in Part I [Funct Anal Other Math 1(2):93–109 ([2006])] and give the explicit formulas for X
p
(a,b).
相似文献
140.
Serena Fiorito Francesco Epifano Francesca Preziuso Vito Alessandro Taddeo Claudio Santi Salvatore Genovese 《Tetrahedron letters》2017,58(4):371-374
The chromane core is widely represented in nature being part of a wide array of secondary metabolites of plant, fungal, and bacterial origin. In this paper an improved method for the chemical synthesis of differently substituted chromanes is described. Substituted 2H-1-benzopyrans have been synthesized in good to excellent yields (52–81%) by treatment of 3,3-dimethylallyl and propenylbenzene ethers of differently substituted phenols with phenylselenyl chloride. 相似文献