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991.
Stedall TP Butler MF Woolfson DN Hanna S 《The European physical journal. E, Soft matter》2011,34(1):5-16
We present a coarse-grained computer model designed to study the growth of fibres in a synthetic self-assembling peptide system.
The system consists of two 28 residue a \alpha -helical sequences, denoted AB and CD, in which the interactions between the half peptides, A, B, C and D, may be tuned individually
to promote different types of growth behaviour. In the model, AB and CD are represented by double ended rods, with interaction
sites distributed along their lengths. Monte Carlo simulations are performed to follow fibre growth. It is found that lateral
and longitudinal growth of the fibre are governed by different mechanisms --the former is diffusion limited with a very small
activation energy for the addition of units, whereas the latter occurs via a process of secondary nucleation at the fibre
ends. As a result, longitudinal growth generally proceeds more slowly than lateral growth. Furthermore, it is shown that the
aspect ratio of the growing fibre may be controlled by adjusting the temperature and the relative strengths of the interactions.
The predictions of the model are discussed in the context of published data from real peptide systems. 相似文献
992.
A. Ekstr?m J. Cederk?ll C. Fahlander M. Hjorth-Jensen T. Engeland A. Blazhev P. A. Butler T. Davinson J. Eberth F. Finke A. G?rgen M. Górska A. M. Hurst O. Ivanov J. Iwanicki U. K?ster B. A. Marsh J. Mierzejewski P. Reiter S. Siem G. Sletten I. Stefanescu G. M. Tveten J. Van de Walle D. Voulot N. Warr D. Weisshaar F. Wenander M. Zielińska 《The European Physical Journal A - Hadrons and Nuclei》2010,44(3):355-361
The low-lying states in the odd-odd and unstable isotopes 106, 108In have been Coulomb excited from the ground state and the first excited isomeric state at the REX-ISOLDE facility at CERN. With the additional data provided here the $ \pi$ g 9/2 -1 ? $ \nu$ d 5/2 and $ \pi$ g 9/2 -1 ? $ \nu$ g 7/2 multiplets have been re-analyzed and are modified compared to previous results. The observed $ \gamma$ -ray de-excitation patterns were interpreted within a shell model calculation based on a realistic effective interaction. The agreement between theory and experiment is satisfactory and the calculations reproduce the observed differences in the excitation pattern of the two isotopes. The calculations exclude a 6+ ground state in 106In . This is in agreement with the conclusions drawn using other techniques. Furthermore, based on the experimental results, it is also concluded that the ordering of the isomeric and ground state in 108In is inverted compared to the shell model prediction. Limits on B(E2) values have been extracted where possible. A previously unknown low-lying state at 367keV in 106In is also reported. 相似文献
993.
John Buckeridge Keith T. Butler C. Richard A. Catlow Andrew J. Logsdail David O. Scanlon Stephen A. Shevlin Scott M. Woodley Alexey A. Sokol Aron Walsh 《ChemInform》2015,46(31):no-no
A multiscale quantum‐chemical approach is used for examining the electronic structure of eight known TiO2 polymorphs and aligning their ionization potential and electron affinity relative to an absolute energy reference. 相似文献
994.
995.
Nathan Downs Nawin Raj Jennifer Vanos Alfio V. Parisi Harry Butler Ravinesh Deo Damien Igoe Benjamin Dexter Melanie Beckman-Downs Joanna Turner Stijn Dekeyser 《Photochemistry and photobiology》2023,99(4):1193-1207
Current shading strategies used to protect outdoor playgrounds from harmful solar radiation include the placement of artificial cloth weaves or permanent roofing over a playground site, planting trees in proximity to playground equipment, and using vegetation or surface texture variations to cool playground surfaces. How and where an artificial shade structure is placed or a tree is planted to maximize the shade protection over specific playground areas, requires careful assessment of local seasonal sun exposure patterns. The Playground Shade Index (PSI) is introduced here as a design metric to enable shade and solar ultraviolet exposure patterns to be derived in an outdoor space using conventional aerial views of suburban park maps. The implementation of the PSI is demonstrated by incorporating a machine learning design tool to classify the position of trees from an aerial image, thus enabling the mapping of seasonal shade and ultraviolet exposure patterns within an existing 7180 m2 parkland. This is achieved by modeling the relative position of the sun with respect to nearby buildings, shade structures, and the identified evergreen and deciduous tree species surrounding an outdoor playground. 相似文献