排序方式: 共有63条查询结果,搜索用时 15 毫秒
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Dr. Laia Vilà‐Nadal Dr. Scott G. Mitchell Dr. Stanislav Markov Dr. Christoph Busche Dr. Vihar Georgiev Prof. Asen Asenov Prof. Leroy Cronin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(49):16502-16511
We explore the concept that the incorporation of polyoxometalates (POMs) into complementary metal oxide semiconductor (CMOS) technologies could offer a fundamentally better way to design and engineer new types of data storage devices, due to the enhanced electronic complementarity with SiO2, high redox potentials, and multiple redox states accessible to polyoxometalate clusters. To explore this we constructed a custom‐built simulation domain bridge. Connecting DFT, for the quantum mechanical modelling part, and mesoscopic device modelling, confirms the theoretical basis for the proposed advantages of POMs in non‐volatile molecular memories (NVMM) or flash‐RAM. 相似文献
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The main objective of this study is the determination of elastic moduli and viscosity coefficients of metals at elevating temperature up to melting point. More specifically, it involves the analysis of the propagation of acoustic waves generated and detected simultaneously by laser-ultrasonic for the measurement of longitudinal and shear velocities. This preliminary work primarily concerns Tin (Sn) metal known for its low melting point and attenuation coefficient. 相似文献
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L. de Arcangelis H. J. Herrmann M. Kolb René Thomas C. Amitrano L. Peliti M. Saber G. Weisbuch Sara A. Solla F. Bagnoli A. Francescato R. Livi S. Ruffo Pablo Tamayo Michel Droz Peter Jörg Plath S. Romano Yves Pomeau Stéphane Zaleski D. Stauffer Luciano R. da Silva Alex Hansen Stéphane Roux Antonio Coniglio B. Derrida Henrik Flyvbjerg Naeem Jan Dietrich Stauffer Peter Grassberger A. Zippelius K. E. Kurten Werner Krauth Jean -Pierre Nadal Marc Mézard Per Bak Chao Tang Itzhak Webman M. L. Martins H. F. V. Resende C. Tsallis A. C. N. Magalhaes 《Journal of statistical physics》1989,55(5-6):1333-1359
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A series of vulpinic acids differing by the aryl or heteroaryl groups placed in the ester α-position were prepared by Suzuki-Miyaura cross-coupling involving a common iodide and the corresponding aryl boronates. The preparation of the iodide precursor from (+)-dimethyl l-tartrate required four steps: the esterification of one hydroxyl group, a Dieckmann cyclization allowing the construction of the tetronic acid moiety, a dehydration leading to the installation of the exocyclic double bond and lastly, an N-iodosuccinimide-mediated iodation of the alkene obtained. 相似文献
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Laia Vilà‐Nadal José Pedro Sarasa Dr. Antonio Rodríguez‐Fortea Dr. Joan Igual Dr. Leonid P. Kazansky Dr. Josep M. Poblet Prof. Dr. 《化学:亚洲杂志》2010,5(1):97-104
DFT calculations were carried out to study 183W NMR chemical shifts in the family of the Keggin anions with formula α‐[XW12O40]q? (X=B, Al, Si, P, Ga, Ge, As, Zn), in the β‐ and γ‐[SiW12O40]4? geometric isomers, in the derivative Dawson anion [P2W18O62]6?, and in the most symmetrical Lindqvist [W6O19]2? anion and its derivative [W10O32]4?. In this article, we show that the geometry employed in the calculation of NMR chemical shifts in polyoxotungstates is extremely important if we want to be quantitative. Using very large basis sets of QZ4P quality and taking into account the conductor‐like screening model (COSMO) to account for solvent effects (aqueous and organic solutions), good geometries were found for the polyoxoanions. From these optimal geometries the 183W NMR chemical shifts were computed with the more standard basis sets of TZP quality and including spin–orbit corrections inside the zero‐order regular approximation (ZORA) to describe the relativistic effects of the internal electrons. With this strategy the mean absolute error between experimental and theoretical values was found to be less than 10 ppm, which is similar to the experimental error. We also discuss how the geometry of the polyoxoanion influences on the shielding. 相似文献
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Moreira H Yu Q Nadal B Bresson B Rosticher M Lequeux N Zimmers A Aubin H 《Physical review letters》2011,107(17):176803
We describe current-voltage (I-V) characteristics of alkyl-ligated gold nanocrystals ~5 nm arrays in a long screening length limit. Arrays with different alkyl ligand lengths have been prepared to tune the electronic tunnel coupling between the nanocrystals. For long ligands, electronic diffusion occurs through sequential tunneling and follows activated laws, as a function of temperature σ∝e(-T(0)/T) and as a function of electric field I∝e(-E(0)/E). For better conducting arrays, i.e., with small ligands, the transport properties cross over to the cotunneling regime and follow Efros-Shklovskii laws as a function of temperature σ∝e(-(T(ES)/T)(1/2) and as a function of electric field I∝e(-(E)(ES)/E)(1/2). The data show that electronic transport in nanocrystal arrays can be tuned from the sequential tunneling to the cotunneling regime by increasing the tunnel barrier transparency. 相似文献
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Nadal F Argoul F Kestener P Pouligny B Ybert C Ajdari A 《The European physical journal. E, Soft matter》2002,9(4):387-399
We report a theoretical and experimental study of the hydrodynamic flow induced by an a.c. electric field in the vicinity
of a dielectric stripe deposited on a conducting plate. In the theoretical part, we model the stripe as a small change of
the surface capacitance of the plate, and a perturbative approach is used to perform the calculations. This approach predicts
an outwards rectified electro-osmotic slip along the surface that generates two steady counter-rotating rolls, the size of
which decreases with the frequency. In the experimental section, we use tracers to determine the structure of the flow and
investigate its dependence on the frequency and the amplitude of the applied voltage. The structure and amplitude of the observed
flow compares satisfactorily with the theoretical analysis. This could guide the design of surface-controlled flows and help
to understand the collective behavior of colloids near electrodes.
Received 20 June 2002
RID="a"
ID="a"e-mail: nadal@crpp.u-bordeaux.fr 相似文献
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CM Silva MF Duarte ML Mira MH Florêncio K Versluis AJ Heck 《Rapid communications in mass spectrometry : RCM》1999,13(12):1098-1103
Fast atom bombardment, combined with high-energy collision-induced tandem mass spectrometry, has been used to investigate gas-phase metal-ion interactions with captopril, enalaprilat and lisinopril, all angiotensin-converting enzyme inhibitors.Suggestions for the location of metal-binding sites are presented. For captopril, metal binding occurs most likely at both the sulphur and the nitrogen atom. For enalaprilat and lisinopril, binding preferably occurs at the amine nitrogen. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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A new PCR-CGE (size and color) method for simultaneous detection of genetically modified maize events 总被引:1,自引:0,他引:1
We present a novel multiplex PCR assay for simultaneous detection of multiple transgenic events in maize. Initially, five PCR primers pairs specific to events Bt11, GA21, MON810, and NK603, and Zea mays L. (alcohol dehydrogenase) were included. The event specificity was based on amplification of transgene/plant genome flanking regions, i.e., the same targets as for validated real-time PCR assays. These short and similarly sized amplicons were selected to achieve high and similar amplification efficiency for all targets; however, its unambiguous identification was a technical challenge. We achieved a clear distinction by a novel CGE approach that combined the identification by size and color (CGE-SC). In one single step, all five targets were amplified and specifically labeled with three different fluorescent dyes. The assay was specific and displayed an LOD of 0.1% of each genetically modified organism (GMO). Therefore, it was adequate to fulfill legal thresholds established, e.g., in the European Union. Our CGE-SC based strategy in combination with an adequate labeling design has the potential to simultaneously detect higher numbers of targets. As an example, we present the detection of up to eight targets in a single run. Multiplex PCR-CGE-SC only requires a conventional sequencer device and enables automation and high throughput. In addition, it proved to be transferable to a different laboratory. The number of authorized GMO events is rapidly growing; and the acreage of genetically modified (GM) varieties cultivated and commercialized worldwide is rapidly increasing. In this context, our multiplex PCR-CGE-SC can be suitable for screening GM contents in food. 相似文献