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121.
Henrik Stetkær 《Semigroup Forum》2001,63(3):466-468
No abstract.
November 15, 1999 相似文献
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Simon W. de Leeuw John W. Perram Henrik G. Petersen 《Journal of statistical physics》1990,61(5-6):1203-1222
We derive expressions for the conjugate momenta and the Hamiltonian for classical dynamical systems subject to holonomic constraints. We give an algorithm for correcting deviations of the constraints arising in numerical solution of the equations of motion. We obtain an explicit expression for the momentum integral for constrained systems. 相似文献
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The process of "evolutionary diffusion," i.e., reproduction with local mutation but without selection in a biological population, resembles standard diffusion in many ways. However, evolutionary diffusion allows the formation of localized peaks that undergo drift, even in the infinite population limit. We relate a microscopic evolution model to a stochastic model which we solve fully. This allows us to understand the large population limit, relates evolution to diffusion, and shows that independent local mutations act as a diffusion of interacting particles taking larger steps. 相似文献
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Dr. Vitthal N. Yadav Prof. Angiolina Comotti Prof. Piero Sozzani Dr. Silvia Bracco Prof. Tore Bonge‐Hansen Dr. Martin Hennum Prof. Carl Henrik Görbitz 《Angewandte Chemie (International ed. in English)》2015,54(52):15684-15688
Dipeptides with two hydrophobic side chains have proved to be an exceptional source of microporous organic materials, but since previous structures were limited to the incorporation of only proteinogenic residues, their full potential as adsorbents has remained unexplored. Single‐crystal XRD data for ten new compounds with non‐proteinogenic L ‐2‐aminobutanoic acid and/or L ‐2‐amino‐pentanoic acid are presented. The gas‐phase accessibility of their crystal pores, with cross‐sections of 2.3 to 5.1 Å, was monitored by CO2 and CH4 adsorption isotherms. Included CO2 was also detected spectroscopically by 2D MAS NMR. An extensive conformational analysis reveals that the use of linear rather than branched side chains (such as L ‐valine and L ‐isoleucine) affords peptides with a greater degree of conformational freedom and yields more‐flexible channel surfaces that may easily adapt to a series of potential guest molecules. 相似文献
130.
Fully printed flexible audio system on the basis of low‐voltage polymeric organic field effect transistors with three layer dielectric 下载免费PDF全文
Georg C. Schmidt Daniel Höft Katherina Haase Maxi Bellmann Bahman Kheradmand‐Boroujeni Tomi Hassinen Henrik Sandberg Frank Ellinger Arved C. Hübler 《Journal of Polymer Science.Polymer Physics》2015,53(20):1409-1415
Fully mass printed, flexible and truly polymeric organic field effect transistors consisting of a three layer dielectric made of CYTOP (low‐k), PVA (intermediate) and P(VDF‐TrFE‐CTFE)(high‐k) are introduced. Gravure‐, flexo‐and screen printing were selected as highly productive manufacturing technologies. These OFETs work at strongly reduced voltages and show high field effect mobility (µ = 0.2 cm2/Vs) and remarkable good bias stress stability at very high current density (50 µA/mm). Fully printed OFETs are used for the realization of ring oscillators working in the kHz regime at reduced supply voltage (10 V). In combination with printed fully polymeric piezoelectric loudspeakers, this work shows for the first time fully printed flexible audio systems. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1409–1415 相似文献