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971.
Tran TK Bricaud Q Oçafrain M Blanchard P Roncali J Lenfant S Godey S Vuillaume D Rondeau D 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(20):5628-5640
The synthesis and characterization of a series of quaterthiophenes (4Ts) with thiolate groups protected with 2-cyanoethyl (CNE), 2-trimethylsilylethyl (TMSE), and acetyl (Ac) groups are described. Sequential cleavage of these different protecting groups allows for the preparation of 4Ts derivatized with ferrocene and/or alkanethiol chains. The electrochemical behavior of these compounds has been analyzed in solution by cyclic voltammetry (CV). A ferrocene-derivatized dithiol 4T 14 and a dithiol 4T 15 with two TMSE-protected thiolate groups have been immobilized on a gold surface as monolayers that have been characterized by CV, ellipsometry, contact-angle measurement, and X-ray photoelectron spectroscopy (XPS). The results show that molecules 14 and 15 are doubly grafted with a horizontal orientation of the conjugated system relative to the surface. Furthermore, application of the deprotection/alkylation sequence of the remaining protected thiolate groups on a monolayer of 15 allows for efficient post-functionalization. 相似文献
972.
Shao Z Rannou P Sadki S Fey N Lindsay DM Faul CF 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(44):12512-12521
The simple and elegant Buchwald-Hartwig cross-coupling reaction has been used to synthesise a designed range of new aniline-based tetramers in one step, and without the need for protecting groups. Variation of the central aromatic ring has provided the opportunity to carefully tune the optoelectronic properties in this series, thus enabling a structure-activity relationship study by using a range of photophysical and electrochemical techniques. As a result, the long-proposed sequences of electron-electron (EE) and electron-chemical (EC) processes that support the complex redox and proton-transfer reactions involved in the well-known switching of redox states of poly- and oligo(aniline)s are revealed here for the first time. We also present the initial results from time-dependent DFT calculations to clarify the optoelectronic behaviour of these oligomers. The dc-conductivity measurements of conducting thin films of this series, doped with the prototypical poly(aniline) protonating agent D,L-camphor-10-sulfonic acid (CSA), externally plasticised with triphenyl phosphate (TPP), and processed from m-cresol (MC) solutions, are also presented. 相似文献
973.
Bagag A Giuliani A Canon F Réfrégiers M Le Naour F 《Rapid communications in mass spectrometry : RCM》2011,25(22):3436-3440
Mass spectrometry (MS) has dramatically evolved in the last two decades and has been the driving force of the spectacular expansion of proteomics during this period. However, the very poor compatibility of MS with detergents is still a technical obstacle in some studies, in particular on membrane proteins. Indeed, the high hydrophobicity of membrane proteins necessitates the use of detergents for their extraction and solubilization. Here, we address the analytical potential of high-field asymmetric waveform ion mobility spectrometry (FAIMS) for separating peptides from detergents. The study was focused on peptides from the human integral membrane protein CD9. A tryptic peptide was mixed with the non-ionic detergents Triton X-100 or beta-D-dodecyl maltoside (DDM) as well as with the ionic detergents sodium dodecyl sulfate (SDS) or sodium deoxycholate (SDC). Although electrospray ionization (ESI) alone led to a total suppression of the peptide ion signal on mass spectra with only detection of the detergents, use of FAIMS allowed separation and clear identification of the peptide with any of the detergents studied. The detection and identification of the target compound in the presence of an excess of detergents are then feasible. FAIMS should prove especially useful in the structural and proteomic analysis of membrane proteins. 相似文献
974.
Loïc Foissy 《代数通讯》2013,41(10):4528-4552
We study the Hopf algebra H of Fliess operators coming from Control Theory in the one-dimensional case. We prove that it admits a graded, finite-dimensional, connected grading. Dually, the vector space ? ? x 0, x 1 ? is both a pre-Lie algebra for the pre-Lie product dual of the coproduct of H, and an associative, commutative algebra for the shuffle product. These two structures admit a compatibility which makes ? ? x 0, x 1 ? a Com-Pre-Lie algebra. We give a presentation of this object as a pre-Lie algebra. 相似文献
975.
Ouahiba Zaïr 《Applicable analysis》2013,92(10):2061-2075
We consider an inverse problem of determining point sources in vibrating plate by boundary measurements. We show that the boundary observation of the domain determines uniquely the sources for an arbitrarily small time of observation and we establish a conditional stability. 相似文献
976.
Pedro A. Martínez Martínez V. Fernandez Escartïn T. Pollán Santamaría 《International Journal of Mathematical Education in Science & Technology》2013,44(6):747-748
A new method for the analysis of sinusoidal oscillators, based on a general characterization of feedback electronic systems, is drawn. This exact and algorithmic method allows us to find the oscillation conditions by the calculation of only one transfer function of a circuit which, generally, is obtained by a simple inspection of the system. 相似文献
977.
This article provides in the setting of infinite dimensional Hilbert space, a result concerning the existence and uniqueness of solutions for Lipschitz single-valued perturbations of evolution problems associated with time-dependent subdifferential operators. The result is used to extend to optimal control problems associated with such equations the relaxation theorems with Young measures established in Casting et al. [7, 11] and Edmond and Thibault [11]. 相似文献
978.
In this article, we provide a finer semilocal convergence analysis of a certain class of Broyden-like methods for solving equations containing a nondifferentiable term on the p-dimensional Euclidean space (p ≥ 1, a natural number) [2, 4, 5, 8, 9]. We achieve the goal by using our new idea of recurrent functions. Special cases and applications are also provided. 相似文献
979.
Maïtine Bergounioux 《Numerical Functional Analysis & Optimization》2013,34(5-6):515-543
The aim of this paper is to present a simple qualification condition for control elliptic problems involving constraints both on the control and the state, when there are both a distributed and a boundary control. We establish a general maximum principle and give some examples. Then we study the particular case when the control is only a boundary one and we present a Lagrangian Algorithm with a few numerical results. 相似文献
980.
On the light of a previous work and its recommendations by Matoba et al. [J. Phys. B 41, 145205 (2008)], this paper proposes to look at the mobility of ground and metastable-excited states of C+ ions moving into a helium buffer gas. The calculations, based on the three-temperature theory for solving the Boltzmann kinetic equation, are accomplished with quantum-mechanical transport cross sections at the low temperatures 4.3 and 77?K. The obtained mobility results are contrasted with the available theoretical data and experimental measurements, which show acceptable agreements. 相似文献