975 resultados para Long-range edge percolation model


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Thesis (Master's)--University of Washington, 2016-06

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The edge-to-edge matching model has been further developed along with the Cu/Cr system as an example. The conditions for zigzag atom rows to be matching directions are included and the critical value of interatomic spacing misfit along matching directions and the critical value of d-value mismatch between matching planes are proposed in the new version of the model. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The edge-to-edge matching model for describing the interfacial crystallographic characteristics between two phases that are related by reproducible orientation relationships has been applied to the typical grain refiners in aluminum alloys. Excellent atomic matching between Al3Ti nucleating substrates, known to be effective nucleation sites for primary Al, and the Al matrix in both close packed directions and close packed planes containing these directions have been identified. The crystallographic features of the grain refiner and the Al matrix are very consistent with the edge-to-edge matching model. For three other typical grain refiners for Al alloys, TiC (when a = 0.4328 nm), TiB2 and AIB(2), the matching only occurs between the close packed directions in both phases and between the second close packed plane of the Al matrix and the second close packed plane of the refiners. According to the model, it is predicted that Al3Ti is a more powerful nucleating substrate for Al alloy than TiC, TiB2 and AlB2. This agrees with the previous experimental results. The present work shows that the edge-to-edge matching model has the potential to be a powerful tool in discovering new and more powerful grain refiners for Al alloys. (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The edge-to-edge matching model, which was originally developed for predicting crystallographic features in diffusional phase transformations in solids, has been used to understand the formation of in-plane textures in TiSi2 (C49) thin films on Si single crystal (001)si surface. The model predicts all the four previously reported orientation relationships between C49 and Si substrate based on the actual atom matching across the interface and the basic crystallographic data only. The model has strong potential to be used to develop new thin film materials. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The orientation relationship (OR) between the beta(Zn) phase and the alpha(Al) phase and the corresponding habit planes in a Zn-Al eutectoid alloy were accurately determined using convergent beam Kikuchi line diffraction patterns. In addition to the previously reported OR. [11 (2) over bar0](beta)parallel to[110](alpha), (0002)(beta)parallel to ((1) over bar 11)alpha, two new ORs were observed. They are: [11 (2) over bar0](beta)parallel to [110], ((1) over bar 101)(beta) 0.82 degrees from (002)(alpha) and [(1) over bar 100](beta)parallel to[112](alpha), (0002)(beta) 4.5 degrees from (111)(alpha). These ORs can be explained and understood using the recently developed edge-to-edge matching model. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In coliphage MS2 RNA a long-distance interaction (LDI) between an internal segment of the upstream coat gene and the start region of the replicase gene prevents initiation of replicase synthesis in the absence of coat gene translation. Elongating ribosomes break up the repressor LDI and thus activate the hidden initiation site. Expression studies on partial MS2 cDNA clones identified base pairing between 1427-1433 and 1738-1744, the so-called Min Jou (MJ) interaction, as the molecular basis for the long-range coupling mechanism. Here, we examine the biological significance of this interaction for the control of replicase gene translation. The LDI was disrupted by mutations in the 3'-side and the evolutionary adaptation was monitored upon phage passaging. Two categories of pseudorevertants emerged. The first type had restored the MJ interaction but not necessarily the native sequence. The pseudorevertants of the second type acquired a compensatory substitution some 80 nt downstream of the MJ interaction that stabilizes an adjacent LDI. In one examined case we confirmed that the second site mutations had restored coat-replicase translational coupling. Our results show the importance of translational control for fitness of the phage. They also reveal that the structure that buries the replicase start extends to structure elements bordering the MJ interaction.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT

Relevância:

100.00% 100.00%

Publicador:

Resumo:

DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Everyday human behaviour relies on our ability to predict outcomes on the basis of moment by moment information. Long-range neural phase synchronization has been hypothesized as a mechanism by which ‘predictions’ can exert an effect on the processing of incoming sensory events. Using magnetoencephalography (MEG) we have studied the relationship between the modulation of phase synchronization in a cerebral network of areas involved in visual target processing and the predictability of target occurrence. Our results reveal a striking increase in the modulation of phase synchronization associated with an increased probability of target occurrence. These observations are consistent with the hypothesis that long-range phase synchronization plays a critical functional role in humans' ability to effectively employ predictive heuristics.