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221.
V. I. Ryazanov 《Ukrainian Mathematical Journal》1992,44(10):1292-1298
A positive answer is given to the Reich-Walczak problem relative to conformality in the Belinskii-Lavrent'ev sense of quasiconformal mappings at a point in the case of an arbitrary modulus of the complex characteristic and under an appropriate selection of its argument.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 44, No. 10, pp. 1406–1411, October, 1992. 相似文献
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223.
Monte Carlo simulations have been carried out to study the growth kinetics after a rapid quench of a system with nonconserved order parameter into a steady state characterized by a thermal gradient. Both the Allen-Cahn growth law for the average domain size as well as the scaling behavior, typical for systems evolving towards equilibrium, are observed. Some aspects of different spinupdating algorithms are briefly discussed. 相似文献
224.
New concepts for the study of incompressible plane or axisymmetric flows are analysed by the stream tube method. Flows without eddies and pure vortex flows are considered in a transformed domain where the mapped streamlines are rectilinear or circular. The transformation between the physical domain and the computational domain is an unknown of the problem. In order to solve the non-linear set of relevant equations, we present a new algorithm based on a trust region technique which is effective for non-convex optimization problems. Experimental results show that the new algorithm is more robust compared to the Newton-Raphson method. 相似文献
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228.
T Christensen E B Jensen F Junker H Dalb?ge F Abildgaard J J Led 《Acta chemica Scandinavica (Copenhagen, Denmark : 1989)》1992,46(1):97-99
Biosynthetic human growth hormone specifically 13C-labelled in the carbonyl positions of all 26 leucine residues has been obtained by recombinant DNA techniques using 13C-labelled leucine and an E. coli strain that requires leucine. It is shown that, on the whole, the labelling is specific with no significant mislabelling as would have been the case had the 13C-labelled leucine been metabolized. 相似文献
229.
This investigation presents the preparation of CeN0.222O0.667F1.333 by a solid-state reaction from a mixture of CeN:CeF3:CeO2 = 1:2:1.5 and its structural investigation. The samples were annealed at 900°C in platinum tubes for different times. The basic structure found by powder neutron diffraction is anion-excess fluorite-related. The unit cell is an orthorhombic distortion of the cubic fluorite cell and has the space group Abm2. The lattice constants are a = 577.71(2) pm, B = 572.76(5) pm, and c = 573.32(6) pm. The structure refined by Rietveld analysis shows that [1:0:2]- defect clusters are present. In samples prepared by longer annealing times an ordering of these clusters to larger aggregates, i.e., toward the vernier phases, was observed. This was deduced from full profile analysis without refining a structural model by comparing the instrumental resolution curves of several models. 相似文献
230.
Yu. V. Zhitnikov Yu. I. Zetser 《Journal of Applied Mechanics and Technical Physics》1992,33(6):787-792
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, No. 6, pp. 22–28, November–December, 1992. 相似文献