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11.
We have investigated the mean-field dynamics of an overdamped viscoelastic medium driven through quenched disorder. The model allows for the coexistence of pinned and sliding regions and can exhibit continuous elastic depinning or first-order hysteretic depinning. Numerical simulations indicate mean-field instabilities that correspond to macroscopic stick-slip events and lead to premature switching. The model describes the elastic and plastic dynamics of driven vortex arrays in superconductors and other extended disordered systems. 相似文献
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Richard W. Middleton John Parrick Eric D. Clarke Peter Wardman 《Journal of heterocyclic chemistry》1986,23(3):849-855
A number of novel N-substituted-1,8-naphthalimides have been prepared and their fluorescence yields measured in water at pH 7.4. The type of substitutent and the substitution pattern on the naphthalimide nucleus produce markedly different fluorescence yields, (quantum efficiencies, ø varying from ø = 0-0037 for N-(3-N'-morpholino-1-propyl)-4-amino-3-methoxy-1,8-naphthalirnide (7) to ø = 0–77 for N-(3-bromopropyl)-4-acetamido-1,8-naphthalimide (31). 相似文献
14.
M. B. Rane K. Kondaiah A. R. Middleton G. T. Wernimont S. L. Archangelowa M. Stschigol N. Dubinski L. W. N. Godward A. M. Ward A. D. Worobjewa P. Wukolow A. Reich N. A. Tananajew F. P. Dwyer R. H. Bullard J. S. Knapper K. A. Craig G. C. Chandlee W. I. Kosakow L. Szebellédy M. Ajtai M. Uljanitschew M. S. Platonow N. F. Kriwoschlykow A. A. Marakajew M. J. Petrow K. M. Rauner 《Analytical and bioanalytical chemistry》1939,117(3-4):118-132
15.
D. G. Middleton J. R. M. Annand C. Barbieri P. Barneo P. Bartsch D. Baumann J. Bermuth D. Bosnar H. P. Blok R. Böhm M. Ding M. O. Distler D. Elsner J. Friedrich C. Giusti D. I. Glazier P. Grabmayr S. Grözinger T. Hehl J. Heim W. H. A Hesselink E. Jans F. Klein M. Kohl L. Lapikás I. J. D. MacGregor I. Martin J. C. McGeorge H. Merkel P. Merle F. Moschini U. Müller Th. Pospischil G. Rosner H. Schmieden M. Seimetz A. Süle H. de Vries Th. Walcher D. P. Watts M. Weis B. Zihlmann 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):469-469
16.
Robert W. HumbleDanielle F. Middleton Joseph BanoubDavid F. Ewing Andrew N. Boa Grahame Mackenzie 《Tetrahedron letters》2011,52(47):6223-6227
Bredinin (4-carbamoyl-1-β-d-ribofuranosylimidazolium-5-olate, 1) was synthesised by the formation of a malonamate from 2,3-isopropylidene-d-ribofuranosylamine and ethyl malonyl chloride, followed by a sequence involving amination, via reduction of an oxime, heterocycle formation and then deprotection. 相似文献
17.
Middleton DA 《Magnetic resonance in chemistry : MRC》2011,49(2):65-69
Solid‐state nuclear magnetic resonance (SSNMR) is a powerful technique for the structural analysis of amyloid fibrils. With suitable isotope labelling patterns, SSNMR can provide constraints on the secondary structure, alignment and registration of β‐strands within amyloid fibrils and identify the tertiary and quaternary contacts defining the packing of the β‐sheet layers. Detection of 14N? 13C dipolar couplings may provide potentially useful additional structural constraints on β‐sheet packing within amyloid fibrils but has not until now been exploited for this purpose. Here a frequency‐selective, transfer of population in double resonance SSNMR experiment is used to detect a weak 14N? 13C dipolar coupling in amyloid‐like fibrils of the peptide H2N‐SNNFGAILSS‐COOH, which was uniformly 13C and 15N labelled across the four C‐terminal amino acids. The 14N? 13C interatomic distance between leucine and asparagine side groups is constrained between 2.4 and 3.8 Å, which allows current structural models of the β‐spine arrangement within the fibrils to be refined. This procedure could be useful for the general structural analysis of other proteins in condensed phases and environments, such as biological membranes. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
18.
J. K. Li Hui Hong B. K. Middleton J. J. Miles 《Journal of magnetism and magnetic materials》1993,120(1-3):206-209
A recording system has been modelled which employs a peak detection scheme consisting of differentiator and cossover detector. The recording behaviours of head and tape combinations are included as variables and the effect of these on overall system error rates have been computed. 相似文献
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20.
H. Gr?ssler D. Lanske R. Schulte G.T. Jones R.P. Middleton S.W. ONeale K. B?ckmann W. Gebel C. Geich-Gimbel B. Nellen A. Grant H. Klein D.R.O. Morrison P. Schmid H. Wachsmuth J.S. Chima M.M. Mobayyen J. Wells 《Nuclear Physics B》1983,223(2):269-295
In an experiment with the hydrogen bubble chamber BEBC at CERN multiplicities of hadrons produced in νp and interactions have been investigated. Results are presented on the multiplicities of charged hadrons and neutral pions, forward and backward multiplicities of charged hadrons and correlations between forward and backward multiplicities. Comparisons are made with hadronic reactions and e+e? annihilation. In the framework of the quark-parton model the data imply similar charged multiplicities for the fragments of a u- and a d-quark, and a larger multiplicities for the fragments of a uu- than for a ud-diquark. The correlation data suggest independent fragmentation of the quark and diquark for hadronic masses above ~ 7 GeV and local charge compensation within an event. 相似文献