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911.
912.
Maurel V Jouni M Baran P Onofrio N Gambarelli S Mouesca JM Djurado D Dubois L Jacquot JF Desfonds G Kulszewicz-Bajer I 《Physical chemistry chemical physics : PCCP》2012,14(4):1399-1407
Magnetic properties of a doped linear polyarylamine (PA2), whose chain includes alternating para-phenylene and meta-phenylene groups, and of two cyclic and linear model compounds (C2 and D2) were explored by pulsed-EPR nutation spectroscopy, SQUID magnetometry and DFT calculations. Stoichiometrically doped PA2 samples exhibit a pure S = 1 state (exchange coupling constant J = 18 K) with a high spin concentration (0.65) corresponding to 65% of mers bearing holes. Such properties were already observed for doped reticulated polyarylamines but are quite unusual for doped linear polyarylamines. In order to better understand the properties of PA2, model compounds C2 and D2 were also investigated: pure S = 1 spin states could also be obtained, but with higher J (respectively 57 K and 35 K) and, surprisingly, with high but still limited spin concentrations (respectively 0.77 and 0.65). 相似文献
913.
Bertrand L Robinet L Cohen SX Sandt C Le Hô AS Soulier B Lattuati-Derieux A Echard JP 《Analytical and bioanalytical chemistry》2011,399(9):3025-3032
The study of varnishes from musical instruments presents the difficulty of analysing very thin layers of heterogeneous materials
on samples most of which are generally brittle and difficult to prepare. Such study is crucial to the understanding of historical
musical instrument varnishing practices since written sources before 1800 are very rare and not precise. Fourier-transform
infrared (FTIR) spectroscopy and imaging methods were applied to identify the major chemical components within the build-up
of the varnish layers on a cello made by one of the most prominent French violin-makers of the eighteenth century (Jacques
Boquay, ca. 1680–1730). Two types of FTIR imaging methods were used: scanning with a synchrotron-based microscope and full-field
imaging using a 2D imager with a conventional source. An interpretation of the results obtained from these studies on the
Boquay cello is that the maker first applied a proteinaceous layer, probably gelatine-based animal glue. He later applied
a second layer based on a mixture of a drying oil and diterpenic resin from Pinaceae sp. From an historical perspective, the results complement previous studies by describing a second technique used for musical
instrument finishes at the beginning of the eighteenth century in Europe. 相似文献
914.
915.
916.
Gautier B Miteva MA Goncalves V Huguenot F Coric P Bouaziz S Seijo B Gaucher JF Broutin I Garbay C Lesnard A Rault S Inguimbert N Villoutreix BO Vidal M 《Chemistry & biology》2011,(12):1631-1639
Protein-protein interactions play a central role in medicine, and their modulation with small organic compounds remains an enormous challenge. Because it has been noted that the macromolecular complexes modulated to date have a relatively pronounced binding cavity at the interface, we decided to perform screening experiments over the vascular endothelial growth factor receptor (VEGFR), a validated target for antiangiogenic treatments with a very flat interface. We focused the study on the VEGFR-1 D2 domain, and 20 active compounds were identified. These small compounds contained a (3-carboxy-2-ureido)thiophen unit and had IC50 values in the low micromolar range. The most potent compound inhibited the VEGF-induced VEGFR-1 transduction pathways. Our findings suggest that our best hit may be a promising scaffold to probe this macromolecular complex and for the development of treatments of VEGFR-1-dependent diseases. 相似文献
917.
In this work, we present theoretical simulations of laser-driven vibrational control of NO adsorbed on a gold surface. Our goal is to tailor laser pulses to selectively excite specific modes and vibrational eigenstates, as well as to favor photodesorption of the adsorbed molecule. To this end, various control schemes and algorithms are applied. For adsorbates at metallic surfaces, the creation of electron-hole pairs in the substrate is known to play a dominant role in the transfer of energy from the system to the surroundings. These nonadiabatic couplings are included perturbatively in our reduced density matrix simulations using a generalization of the state-resolved position-dependent anharmonic rate model we recently introduced. An extension of the reduced density matrix is also proposed to provide a sound model for photodesorption in dissipative systems. 相似文献
918.
Yen H Seo Y Guillet-Nicolas R Kaliaguine S Kleitz F 《Chemical communications (Cambridge, England)》2011,47(37):10473-10475
We report here on an efficient one-step-impregnation method to synthesize crystalline mesoporous bimetal oxides (e.g. NiFe(2)O(4), CuFe(2)O(4), Cu/CeO(2)) using mesoporous silicas as hard templates under optimized mixing conditions. This new procedure enables a true replication of the mesostructure with high yield and phase purity, while retaining particle morphology of the template. 相似文献
919.
Parizel N Ramírez J Burg C Choua S Bernard M Gambarelli S Maurel V Brelot L Lehn JM Turek P Stadler AM 《Chemical communications (Cambridge, England)》2011,47(39):10951-10953
Depending on the Cu(II)/ligand molar ratio, a pyrimidine-based ligand generates a tetranuclear grid (1/1) or a dinuclear stick (2/1). EPR, MS and visible spectroscopy studies suggest that dilution produces partial dissociation of the grid in solution. Replacement of 2-H-pyrimidine by a 2-phenyl-triazine unit prevents the dissociation of the grid. All these factors influence the magnetic properties of the architectures herein involved. 相似文献
920.
Holzinger M Baur J Haddad R Wang X Cosnier S 《Chemical communications (Cambridge, England)》2011,47(8):2450-2452
Single walled carbon nanotubes were functionalized with different functionalities by simple dip coating. This fast and reproducible procedure was realized with nanotube coated electrodes for the construction of polyvalent biosensors. Three different pyrene derivatives were attached to the nanotube sidewalls by π-stacking interactions in a one-step reaction. 相似文献