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921.
922.
Topographical structures were created on the surface of multi-walled carbon nanotube-based coatings deposited on borosilicate glass using the direct laser interference patterning (DLIP) technique. Films made by multi-walled carbon nanotubes (MWNTs) dispersed in antimony-doped tin oxide (ATO) matrix and networks of MWNTs with both low and high adherence to the substrates were irradiated with one single laser pulse. Due to the high absorption coefficient of ATO, the film was completely removed at the interference maxima positions leading to periodic arrays of high quality on macroscopic areas. Additionally, increase of the laser fluence has produced wider ablated regions. Irradiation of high adherent networks of MWNTs produced a periodic porous structure, what has been attributed to the presence of adherence promoters in the film. On the other hand, MWNT networks with low adhesion to the substrate were strongly removed at the interference maxima positions. In this case, however, the fabricated periodic structures presented several defects that result from the poor adherence of the film to the substrate. 相似文献
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924.
Adam S. Vincek 《Tetrahedron letters》2009,50(36):5107-5109
Mixed trifluoroacetyl phenylacetyl anhydride and 3-halostyrenes (fluoro, chloro, and bromo) or vinylcycloalkanes (cyclohexyl and cyclooctyl), undergo cascade Friedel-Crafts cycli-acylalkylation, enolization, and O-acylation to give 4-substituted tetralen-2-ol phenylacetates, without additional solvent in good yields. Base alcoholysis of 4-phenyltetralen-2-ol phenylacetate reveals the tetral-2-one for asymmetric transfer hydrogenation. Bromophenyltetralen-2-ol phenylacetate undergoes Suzuki coupling, and provides a short route to trans-4-phenyl-β-aminotetralin. 相似文献
925.
Mark S. Friedrichs Peter Eastman Vishal Vaidyanathan Mike Houston Scott Legrand Adam L. Beberg Daniel L. Ensign Christopher M. Bruns Vijay S. Pande 《Journal of computational chemistry》2009,30(6):864-872
We describe a complete implementation of all‐atom protein molecular dynamics running entirely on a graphics processing unit (GPU), including all standard force field terms, integration, constraints, and implicit solvent. We discuss the design of our algorithms and important optimizations needed to fully take advantage of a GPU. We evaluate its performance, and show that it can be more than 700 times faster than a conventional implementation running on a single CPU core. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 相似文献
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In this paper we discuss a minmax regret version of the single-machine scheduling problem with the total flow time criterion. Uncertain processing times are modeled by closed intervals. We show that if the deterministic problem is polynomially solvable, then its minmax regret version is approximable within 2. 相似文献
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