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91.
We show that the equality m1(f(x))=m2(g(x))m1(f(x))=m2(g(x)) for xx in a neighborhood of a point aa remains valid for all xx provided that ff and gg are open holomorphic maps, f(a)=g(a)=0f(a)=g(a)=0 and m1,m2m1,m2 are Minkowski functionals of bounded balanced domains. Moreover, a polynomial relation between ff and gg is obtained.  相似文献   
92.
A systematic study of the accuracy factors for the computation of 15N NMR chemical shifts in comparison with available experiment in the series of 72 diverse heterocyclic azines substituted with a classical series of substituents (CH3, F, Cl, Br, NH2, OCH3, SCH3, COCH3, CONH2, COOH, and CN) providing marked electronic σ‐ and π‐electronic effects and strongly affecting 15N NMR chemical shifts is performed. The best computational scheme for heterocyclic azines at the DFT level was found to be KT3/pcS‐3//pc‐2 (IEF‐PCM). A vast amount of unknown 15N NMR chemical shifts was predicted using the best computational protocol for substituted heterocyclic azines, especially for trizine, tetrazine, and pentazine where experimental 15N NMR chemical shifts are almost totally unknown throughout the series. It was found that substitution effects in the classical series of substituents providing typical σ‐ and π‐electronic effects followed the expected trends, as derived from the correlations of experimental and calculated 15N NMR chemical shifts with Swain–Lupton's F and R constants.  相似文献   
93.
Simplify the proof on the domain of convergence of multiple power series and consider the case where some of z1, · · · , zn are contained only in a finite number of terms of the series. Obtain some results on holomorphic functions in Cn.  相似文献   
94.
We generalize Frobenius singular theorem due to Malgrange, for a large class of codimension one holomorphic foliations on singular analytic subsets of ℂ N . This research was partially supported by Pronex.  相似文献   
95.
汪悦 《数学学报》2007,50(4):887-894
本文研究Coupled Vortex方程的Dirichlet问题,通过热流方法来讨论该方程Dirichlet问题的解的存在唯一性.  相似文献   
96.
利用五个泛函的不动点定理,研究一类含有各阶导数的2m阶微分方程边值问题的三个单调正解的存在性.  相似文献   
97.
甘宁 《数学研究》2007,40(3):284-289
研究了具有任意基本群的非主Hopf流形上的全纯线丛.我们利用推广了Douady序列,利用群作用的方法,具体给出了一类具有非交换基本群的Hopf曲面上全纯线丛上同调维数的计算公式。  相似文献   
98.
We consider paths of functionals starting with one which is invariant under the action of an arbitrary group of symmetries. We give conditions for the existence of an unbounded sequence of critical values of the non-symmetric functional at the end of the path in terms of the growth of the critical values of the symmetric one. We apply this to obtain a multiplicity result for a system of elliptic equations whose symmetries are perturbed by a linear term and a non-homogeneous boundary condition.  相似文献   
99.
Two novel smoothness measures for surfaces are presented in this paper. The second and third order smoothness are defined as the squared normal curvature and the squared variation in normal curvature integrated over all directions in the tangent plane. Both quantities are truly geometric in the sense that they are invariant with respect to the actual parametrization of the surface. All the same, all formulae are derived in terms of an arbitrary parametrization. In addition to providing a basis for variational surface construction, the second and third order smoothness can also be used for evaluation and assessment of the quality of an existing surface. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
100.
A zero set of a holomorphic vector field is totally degenerate, if the endomorphism of the conormal sheaf induced by the vector field is identically zero. By studying a class of foliations generalizing foliations of C*-actions, we show that if a projective manifold admits a holomorphic vector field with a smooth totally degenerate zero component,then the manifold is stably birational to that component of the zero set.When the vector field has an isolated totally degenerate zero, we prove that the manifold is rational. This is a special case of Carrell's conjecture.  相似文献   
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