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91.
92.
A. Küntzel 《Colloid and polymer science》1941,96(2-3):273-284
Ohne Zusammenfassung 相似文献
93.
Michael Struwe 《Calculus of Variations and Partial Differential Equations》2003,16(4):431-437
Extending our previous work [5] on this subject we show global existence of smooth solutions to the Cauchy problem for wave
maps from the (1 + 2)-dimensional Minkowski space to an arbitrary smooth, compact Riemannian manifold without boundary, for
arbitrary smooth, radially symmetric data.
Received: 14 December 2001 / Accepted: 1 March 2002 / Published online: 6 August 2002 相似文献
94.
Michael S. Donovan Andrew B. Lowe Taylor A. Sanford Charles L. McCormick 《Journal of polymer science. Part A, Polymer chemistry》2003,41(9):1262-1281
A novel bifunctional acrylamido‐based reversible addition–fragmentation chain transfer (RAFT) chain‐transfer agent (CTA), N,N′‐ethylenebis[2‐(thiobenzoylthio)propionamide] (CTA2), has been synthesized and used for the controlled free‐radical polymerization of N,N‐dimethylacrylamide (DMA). A comparative study of CTA2 and the monofunctional CTA N,N‐dimethyl‐s‐thiobenzoylthiopropionamide (CTA1) has been conducted. Polymerizations mediated by CTA1 result in poly(N,N‐dimethylacrylamide) (PDMA) homopolymers with unimodal molecular weight distributions, whereas CTA2 yields unimodal, bimodal, and trimodal distributions according to the extent of conversion. The multimodal nature of the PDMAs has been attributed to termination events and/or chains initiated by primary radicals. The RAFT polymerization of DMA with CTA2 also results in a prolonged induction period that may be attributed to the higher local concentration of dithioester functionalities early in the polymerization. A series of ω‐ and α,ω‐dithioester‐capped PDMAs have been prepared in organic media and subsequently employed as macro‐CTAs for the synthesis of diblock and triblock copolymers in aqueous media with the zwitterionic monomer 3‐[2‐(N‐methylacrylamido)‐ethyldimethylammonio] propane sulfonate (MAEDAPS). Additionally, an ω‐dithioester‐capped MAEDAPS homopolymer has been used as a macro‐CTA for the block polymerization of DMA. To our knowledge, this is the first example of a near‐monodisperse, sulfobetaine‐containing block copolymer prepared entirely in aqueous media. The diblock and triblock copolymers form aggregates in pure water that can be dissociated by the addition of salt, as determined by 1H NMR spectroscopy and dynamic light scattering. In pure water, highly uniform, micellelike aggregates with hydrodynamic diameters of 71–93 nm are formed. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1262–1281, 2003 相似文献
95.
Günter F. Steinke 《Results in Mathematics》2007,51(1-2):111-126
Polster and Steinke [Result. Math., 46 (2004), 103–122] determined the possible Kleinewillingh?fer types of flat Laguerre planes. These types reflect transitivity
properties of groups of certain central automorphisms. We exclude three more types from the list given there with respect
to Laguerre homotheties. This yields a complete determination of all possible single types with respect to Laguerre homotheties
that can occur in flat Laguerre planes. Building on results by M?urer and Hartmann to characterize ovoidal or miquelian Laguerre
planes we further characterize certain flat Laguerre planes in terms of their Kleinewillingh?fer types.
Received: January 16, 2007. Revised: July 26, 2007. 相似文献
96.
97.
The vibrational dynamics of protein folding is analyzed in the framework of Tsallis statistics. We employ exact expressions
for classical harmonic oscillators by considering the unnormalized constraints. As q→1, we show that these approximations agree with the result of Gaussian network model. 相似文献
98.
99.
Keller Teichmann Hans Pfeiffer W. Langenbeck A. Reid Heinrich Menzel Th. Höpner W. Mühlsteph M. Ulmann Geib R. E. Liesegang 《Colloid and polymer science》1939,87(1):100-104
Ohne Zusammenfassung 相似文献
100.