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81.
Yu Chen 《Transactions of the American Mathematical Society》1996,348(2):521-541
It is shown that every automorphism of an adjoint Chevalley group over an integral domain containing the rational number field is uniquely expressible as the product of a ring automorphism, a graph automorphism and an inner automorphism while every isomorphism between simple adjoint Chevalley groups can be expressed uniquely as the product of a ring isomorphism, a graph isomorphism and an inner automorphism. The isomorphisms between the elementary subgroups are also found having analogous expressions.
82.
83.
We prove the existence of canonical scrolls; that is, scrolls playing the role of canonical curves. First of all, they provide the geometrical version of Riemann Roch Theorem: any special scroll is the projection of a canonical scroll and they allow to understand the classification of special scrolls in PN. Canonical scrolls correspond to the projective model of canonical geometrically ruled surfaces over a smooth curve. We also prove that the generic canonical scroll is projectively normal except in the hyperelliptic case and for very particular cases in the nonhyperelliptic situation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
84.
A. V. Mitin 《Mathematical Notes》1998,63(3):363-369
The undecidability of the elementary theory of the automorphism group for a Lebesgue space is proved. It is shown that arithmetic
can be interpreted in this theory. The technique of proof can be carried over to certain other groups.
Translated fromMatematicheskie Zametki, Vol. 63, No. 3, pp. 414–420, March, 1998.
The author wishes to thank the participants of the seminar on dynamical systems headed by D. V. Anosov, R. I. Grigorchuk,
and A. M. Stepin as well as the participants of the Kolmogorov seminar of the Mechanics and Mathematics Department of Moscow
State University for discussion of this work. The author is also indebted to N. K. Vereshchagin and A. M. Stepin for support
and valuable remarks as well as to V. V. Ryzhikov for setting the problem and for his assistance. 相似文献
85.
Weierstrass不等式的新推广 总被引:2,自引:0,他引:2
石焕南 《数学的实践与认识》2002,32(1):132-135
利用控制不等式理论将 Weierstrass不等式 ∏ni=1( 1± xi) >1± ∑ni=1xi推广到一般初等对称函数上 ,并且给出一个上界估计 . 相似文献
86.
Tsuneyuki Sato Masahiko Hashimoto Makiko Seno Tomohiro Hirano 《Journal of polymer science. Part A, Polymer chemistry》2003,41(12):1819-1830
The polymerizations of α‐ethyl β‐N‐(α′‐methylbenzyl)itaconamates carrying (RS)‐ and (S)‐α‐methylbenzylaminocarbonyl groups (RS‐EMBI and S‐EMBI) with dimethyl 2,2′‐azobisisobutyrate (MAIB) were studied in methanol (MeOH) and in benzene kinetically and with electron spin resonance (ESR) spectroscopy. The initial polymerization rate (Rp) at 60 °C was given by Rp = k[MAIB]0.58 ± 0.05[RS‐EMBI]2.4 ± 0.l and Rp = k[MAIB]0.61 ± 0.05[S‐EMBI]2.3 ± 0.l in MeOH and Rp = k[MAIB]0.54 ± 0.05[RS‐EMBI]1.7 ± 0.l in benzene. The rate constants of initiation (kdf), propagation (kp), and termination (kt) as elementary reactions were estimated by ESR, where kd is the rate constant of MAIB decomposition and f is the initiator efficiency. The kp values of RS‐EMBI (0.50–1.27 L/mol s) and S‐EMBI (0.42–1.32 L/mol s) in MeOH increased with increasing monomer concentrations, whereas the kt values (0.20?7.78 × 105 L/mol s for RS‐EMBI and 0.18?6.27 × 105 L/mol s for S‐EMBI) decreased with increasing monomer concentrations. Such relations of Rp with kp and kt were responsible for the unusually high dependence of Rp on the monomer concentration. The activation energies of the elementary reactions were also determined from the values of kdf, kp, and kt at different temperatures. Rp and kp of RS‐EMBI and S‐EMBI in benzene were considerably higher than those in MeOH. Rp of RS‐EMBI was somewhat higher than that of S‐EMBI in both MeOH and benzene. Such effects of the kinds of solvents and monomers on Rp were explicable in terms of the different monomer associations, as analyzed by 1H NMR. The copolymerization of RS‐EMBI with styrene was examined at 60 °C in benzene. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1819–1830, 2003 相似文献
87.
88.
Frederik Herzberg 《Mathematical Logic Quarterly》2008,54(6):666-667
?o?'s theorem for bounded D ‐ultrapowers, D being the ultrafilter introduced by Kanovei and Shelah [4], is established. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
89.
Thermally stimulated recovery behaviour of amorphous polymers is described in terms of a continuous distribution of sharply defined elementary softening processes in the polymer. It is proposed that each of these elementary processes is the result of a co-operative site-change mechanism. On exceeding the activation temperature for the process, the viscoelastic time constants fall abruptly by many orders of magnitude, as opposed to following an Arrhenius-type law. The implications of this type of behaviour are discussed.
Prof. Schwarzl zum 60. Geburtstag gewidmet. 相似文献
90.
Qin Jun 《Mathematical Logic Quarterly》1992,38(1):305-320
The author establishes an elementary system AS which contains functions +, ? and a constant 0 and then proves the semi-completeness and the decidability of AS, using the theory of systems of inequalities. 相似文献