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101.
Back Cover: Quadruplex DNA‐Stabilising Dinuclear Platinum(II) Terpyridine Complexes with Flexible Linkers (Chem. Eur. J. 7/2016) 下载免费PDF全文
102.
Trialkylsilyl triflimides generated in situ are unique catalysts for the electrophilic benzylation or allylation of trialkylsilylenol ethers or allyl trialkylsilanes with non-genotoxic alkylating reagents such as benzyl and allyl acetates. In most cases the reactions are fast at room temperature and yields are high. The reaction works particularly well with electron-rich benzyl donors including derivatives of pyrrole, indole and furane. 相似文献
103.
Hilda R. Morales Martín Pérez-Juárez Laura Cuéllar Lourdes Mendoza Héctor Fernández Rosalinda Contreras 《合成通讯》2013,43(13):1213-1219
A new procedure for the high-yield N-monoalkylation of primary aromatic and aliphatic amines is described. 相似文献
104.
Karla Calfumán Macarena García Maria J. Aguirre Betty Matsuhiro Leonora Mendoza Mauricio Isaacs 《Electroanalysis》2010,22(3):338-344
This work describes electrocatalytic detection of S(IV) compounds in water‐ethanol solutions under acidic conditions, on a glassy carbon electrode modified with Co(II) tetraruthenated porphyrin electrostatically assembled onto a Nafion film. The Ipc current shows a linear relationship with the concentration of S(IV) oxo‐anions. Controlled potential electrolysis shows that thiosulfate was detected as reaction product. Rotating disk electrode and UV‐visible spectroelectrochemistry experiments showed a kinetic limitation to the electron transfer controlled by charge propagation in the film and the formation of an intermediary between Co center and S(IV) species. The reproducibility of the modification methodology presents a RSD of 4.1%. 相似文献
105.
A fractional algorithm is described which optimizes the cutting of boards or lumber into dimension parts. The model is an extension of previously developed models and is purposely designed for cutting scenarios where the customer order for the dimension parts can be satisfied within a given range, i.e., flexible rather than exact demand. An illustrative example is presented simply to describe the model and compare results between the standard procedure and the modified procedure proposed in this paper. 相似文献
106.
P. Mendoza Zélis G. A. Pasquevich A. Veiga M. B. Fernández van Raap F. H. Sánchez 《Hyperfine Interactions》2010,195(1-3):161-165
Mössbauer absorption line tracking methodology, under a constant velocity strategy, is used for a quasi-continuous observation of the $\upalpha $ -transition on slightly non stoichiometric Fe1?+?x S alloy. To this end, two strategies were applied: an intelligent absorption line tracking with a control algorithm that uses the data measured in the previous region to establish the position of the next partial spectral range; and a predetermined line tracking in which temperature evolution of a partial spectral region of interest (ROI) is programmed. The latter uses results from the former, in order to achieve a quasi-continuous partial spectral observation. These experiments clearly demonstrate that line tracking allows a more efficient use of the radioactive source, as the effort is concentrated in a partial region of the spectra from which the desired information can be obtained. 相似文献
107.
Arfaoui I Bermúdez V Bottari G De Nadai C Jalkanen JP Kajzar F Leigh DA Lubomska M Mendoza SM Niziol J Rudolf P Zerbetto F 《The journal of physical chemistry. B》2006,110(15):7648-7652
Surface enhanced second harmonic generation (SE SHG) experiments on molecular structures, macrocycles, catenanes, and rotaxanes, deposited as monolayers and multilayers by vacuum sublimation on silver, are reported. The measurements show that the molecules form ordered thin films, where the highest degree of order is observed in the case of macrocycle monolayers and the lowest in the case of rotaxane multilayers. The second harmonic generation activity is interpreted in terms of electric field induced second harmonic (EFISH) generation where the electric field is created by the substrate silver atoms. The measured second order nonlinear optical susceptibility for a rotaxane thin film is compared with that obtained by considering only EFISH contribution to SHG intensity. The electric field on the surface of a silver layer is calculated by using the Delphi4 program for structures obtained with TINKER molecular mechanics/dynamics simulations. An excellent agreement is observed between the calculated and the measured SHG susceptibilities. 相似文献
108.
109.
Reza-San German C Santiago P Ascencio JA Pal U Pérez-Alvarez M Rendón L Mendoza D 《The journal of physical chemistry. B》2005,109(37):17488-17495
Graphite-filled MoS2 nanotubes were synthesized by pyrolizing propylene inside MoS2 nanotubes prepared by a template-assisted technique. The large coaxial nanotubes were constituted of graphite sheets inserted between the MoS2 layers, forming the outer part, and coaxial multiwall carbon nanotubes intercalated with MoS2 inside. High-resolution electron microscopy (HREM) and electron energy loss spectroscopy techniques along with molecular dynamics simulation and quantum mechanical calculations were used to characterize the samples. The one-dimensional structures exhibit diverse morphologies such as long straight and twisted nanotubes with several structural irregularities. The interplanar spacing between the MoS2 layers was found to increase from 6.3 to 7.4 A due to intercalation with carbon. Simulated HREM images revealed the presence of mechanical strains in the carbon-intercalated MoS2 layers as the reason for obtaining these twisted nanostructures. The mechanism of formation of carbon-intercalated MoS2 tubular structures and their stability and electronic properties are discussed. Our results open up the possibility of using MoS2 nanotubes as templates for the synthesis of new one-dimensional binary-phase systems. 相似文献
110.
Jun-Hui He Vidal Salazar Mendoza 《Journal of polymer science. Part A, Polymer chemistry》1996,34(13):2809-2816
A novel hybrid photoinitiator, p-benzoyldiphenyliodonium hexafluorophosphate (PhCOPhI+PhPF−6), was synthesized, characterized, and studied. It absorbs UV light not only below 300 nm, but above 300 nm as well. When exposed to UV light, it undergoes an asymmetrical photocleavage to produce cation-radicals and radicals which could induce cationic and radical polymerizations respectively. Compared with the simple iodonium salt PhI+PhPF−6, and bimolecular sensitization system PhCOPh/PhI+PhPF−6, the covalently bonded photosensitization system PhCOPhI+PhPF−6 is much more efficient as a photoinitiator. Oxygen has a small negative effect on the cationic polymerization photoinitiated by PhCOPhI+PhPF−6, while isopropanol has a small positive influence only in argon atmosphere. © 1996 John Wiley & Sons, Inc. 相似文献