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991.
We present an extensive theoretical study of a series of phenothiazine derivatives adsorbed on Au(111). A series of experimentally
accessible quantities are calculated (ultra-violet photoemission spectra, scanning tunneling microscopy images). All simulations
were performed by using DFT techniques and LCAO expansion of the molecular orbitals. The microscopic picture established in
this work provides a deeper understanding of the interfacial processes that govern the working principle of single-molecule
electronics and organic electronic devices.
相似文献
992.
This paper uses a rate-type approach of the non-monotone elasticity to describe large and rapid motions of a string made of a phase transforming material like shape memory alloy (SMA). The nucleation mechanism, the propagation of phase boundaries, of longitudinal and transverse front waves are carefully analyzed. The influence of the slope of the equilibrium curve on the growth and decay of the amplitude of the first and second order discontinuities is studied. The nucleation and wave propagation phenomena which accompany the damping effect of SMA string submitted to a sudden transverse motion are numerically investigated. 相似文献
993.
Cristian D. González-Avilés 《Central European Journal of Mathematics》2009,7(4):606-616
We obtain finiteness theorems for algebraic cycles of small codimension on quadric fibrations over curves over perfect fields.
For example, if k is finitely generated over ℚ and X → C is a quadric fibration of odd relative dimension at least 11, then CH
i
(X) is finitely generated for i ≤ 4. 相似文献
994.
Angel J. Satti Noemí A. Andreucetti Andrés E. Ciolino Cristian Vitale Claudia Sarmoria Enrique M. Vallés 《Radiation Physics and Chemistry》2010,79(11):1137-1143
An anionic almost monodisperse linear polydimethylsiloxane (PDMS) was subjected to gamma irradiation under vacuum at room temperature. The molecular weight changes induced by the radiation process have been investigated using size exclusion chromatography (SEC) with refraction index (RI) and multi angle laser light scattering (MALLS) detectors, to obtain the number and weight average molecular weights of the irradiated samples.The analysis of the data indicates that crosslinking reactions predominated over scission reactions. The results obtained by an SEC-RI have confirmed the presence of small, but measurable amounts of scission.A previously developed mathematical model of the irradiation process that accounts for simultaneous scission and crosslinking and allows for both H- and Y-crosslinks, fitted well the measured molecular weight data. This prediction is in accordance with the experimental data obtained by 29Si-Nuclear Magnetic Resonance spectroscopy (NMR) and previously reported data for commercial linear PDMS (Satti et al., 2008). 相似文献
995.
One-pot cyclization of various 2-N-amido-homoallylanilides mediated by 4 equiv of Dess-Martin periodinane produced pyrrolo[1,2-a]quinoxalines (11 examples, up to 93% yield). 相似文献
996.
L. Abate I. Blanco G. Cicala A. Mamo G. Recca A. Scamporrino 《Polymer Degradation and Stability》2010,95(5):798-2395
Some random low molar mass (Mn ≈ 9000 g mol−1) poly(ethersulfoneethersulfone)/poly(ethersulfoneethersulfonebiphenylsulfone) P(ESES)/P(ESESBS) copolymers, with various (25%, 50% and 75%) ESESBS units contents, were synthesized to obtain compounds with higher chain rigidity than PES. The thermal characterization of the prepared copolymers, as well as that of corresponding P(ESES) and P(ESESBS) homopolymers, was performed, and all investigated parameters showed strong dependence on polymer composition.The glass transition temperature (Tg) was calorimetrically determined by DSC technique, and the obtained values increased linearly as function of ESESBS units percentage, thus indicating an increasing chain rigidity.Degradations were carried out in dynamic heating conditions, from 35 °C to 700 °C, in both flowing nitrogen and static air atmosphere, and the characteristic parameters of degradation were determined in order to draw useful information about the overall thermal stability of the studied compounds. The apparent activation energy of degradation (Ea) was obtained by the Kissinger method, and the values found increased linearly as a function of ESESBS content, while the temperature values at 5% mass loss (T5%) showed an opposite linear trend. The results are discussed and interpreted. 相似文献
997.
Ottaviani P Caminati W Favero LB Blanco S López JC Alonso JL 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(3):915-920
The molecular beam Fourier transform microwave spectrum of cyclobutanone-trifluoromethane has been assigned and measured. The carbon atom of trifluoromethane lies in the plane of the heavy atoms of cyclobutanone. The complex is stabilized by one C-H...O=C and two C-H...F-C weak hydrogen bonds. The C-H...O=C interaction, involving one carbonylic oxygen, is studied for the first time in detail with rotationally resolved spectroscopy. The two C-H...F-C weak hydrogen bonds involve two fluorine atoms of trifluoromethane and two hydrogens of the same methylenic group in the alpha position. 相似文献
998.
Cristian E. Gutié rrez Federico Tournier 《Transactions of the American Mathematical Society》2006,358(11):4843-4872
Let be a strictly convex domain and let be a convex function such that det in . The linearized Monge-Ampère equation is where det is the matrix of cofactors of . We prove that there exist and depending only on , and such that for all solutions to the equation .
999.
1000.
Antonio Suma Erik Poppleton Michael Matthies Petr Šulc Flavio Romano Ard A. Louis Jonathan P. K. Doye Cristian Micheletti Lorenzo Rovigatti 《Journal of computational chemistry》2019,40(29):2586-2595
Simulations of nucleic acids at different levels of structural details are increasingly used to complement and interpret experiments in different fields, from biophysics to medicine and materials science. However, the various structural models currently available for DNA and RNA and their accompanying suites of computational tools can be very rarely used in a synergistic fashion. The tacoxDNA webserver and standalone software package presented here are a step toward a long-sought interoperability of nucleic acids models. The webserver offers a simple interface for converting various common input formats of DNA structures and setting up molecular dynamics (MD) simulations. Users can, for instance, design DNA rings with different topologies, such as knots, with and without supercoiling, by simply providing an XYZ coordinate file of the DNA centre-line. More complex DNA geometries, as designable in the cadnano, CanDo and Tiamat tools, can also be converted to all-atom or oxDNA representations, which can then be used to run MD simulations. Though the latter are currently geared toward the native and LAMMPS oxDNA representations, the open-source package is designed to be further expandable. TacoxDNA is available at http://tacoxdna.sissa.it . © 2019 Wiley Periodicals, Inc. 相似文献