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91.
Böker A Elbs H Hänsel H Knoll A Ludwigs S Zettl H Urban V Abetz V Müller AH Krausch G 《Physical review letters》2002,89(13):135502
We investigate the microscopic mechanisms responsible for microdomain alignment in block copolymer solutions exposed to an electric field. Using time-resolved synchrotron small-angle x-ray scattering, we reveal two distinct processes, i.e., grain boundary migration and rotation of entire grains, as the two dominant microscopic mechanisms. The former dominates in weakly segregating systems, while the latter is predominant in strongly segregated systems. The kinetics of the processes are followed as a function of polymer concentration and temperature and are correlated to the solution viscosity. 相似文献
92.
Konrad J. Swanepoel 《Proceedings of the American Mathematical Society》1999,127(7):2155-2162
A hollow axis-aligned box is the boundary of the cartesian product of compact intervals in . We show that for , if any of a collection of hollow axis-aligned boxes have non-empty intersection, then the whole collection has non-empty intersection; and if any of a collection of hollow axis-aligned rectangles in have non-empty intersection, then the whole collection has non-empty intersection. The values for and for are the best possible in general. We also characterize the collections of hollow boxes which would be counterexamples if were lowered to , and to , respectively.
93.
J. Knoll 《Zeitschrift fur Physik C Particles and Fields》1988,38(1):187-192
The initial phase of a ultra-relativistic nucleus-nucleus collision where matter in form of quarks and real gluons is created is described in terms of a phenomenological strings with multiple colour charge sources at their ends. Consequences upon different observables are reviewed and discussed. 相似文献
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The thermal and methyl radical initiated decomposition of biacetyl-d6 were investigated at conversions 5% over the temperature range of 387-412°C and 251–292°C, respectively. The deuterated sample contained 10.5% biacetyl-d5. The reaction products were analyzed by mass spectrometry. The following data could be determined from product ratios: where E is in kcal/mol With reasonable assumptions and literature data Arrhenius parameters for elementary steps were derived and discussed in particular with respect to isotopic effects in H/D-abstraction reactions. 相似文献
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