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991.
D. O. Revin 《Algebra and Logic》2008,47(3):210-227
992.
Selective protection of one of the hydroxyl group in 1,n-symmetrical diols is achieved by P_2O_2/SiO_2-catalyzed reaction of the diol with dihydropyran under solvent-free conditions at room temperature.This selective protection is simple and it occurred under economically cheap conditions in high yield.The deprotected diol is simply obtained by refluxing of this compound in methanol using the same catalyst without any byproduct formation or additional purifications. 相似文献
993.
Anthony To-Ming Lau 《Journal of Functional Analysis》2008,254(10):2513-2533
In this paper, we explore the properties of projections of norm one on general Banach algebras, in particular the relation with conditional expectations for algebras which arise in harmonic analysis. 相似文献
994.
Christian Gutschwager 《Journal of Algebraic Combinatorics》2009,30(2):215-232
In this paper we show that two skew diagrams λ/μ and α/β can represent the same multiplicity free skew character [λ/μ]=[α/β] only in the the trivial cases when λ/μ and α/β are the same up to translation or rotation or if λ=α is a staircase partition λ=(l,l−1,…,2,1) and λ/μ and α/β are conjugate of each other. 相似文献
995.
Let K be an imaginary quadratic field with class number one and ? be a rational prime that splits in K. We prove that mod ?, a system of Hecke eigenvalues occurring in the first cohomology group of some congruence subgroup Γ of SL2(OK) can be realized, up to twist, in the first cohomology with trivial coefficients after increasing the level of Γ by (?). 相似文献
996.
设$\varphi$为群${\rm Aut}(N)$的同态,记$H_\varphi\times N$为群$N$借助于群$H$的半直积.设$G$为有限不可解群,本文证明: 若$G$中最高阶元素个数为40, 则$G$同构于下列群之一:(1)~$Z_{4\varphi}\times A_5$,\,${\rm ker}\varphi=Z_2$; (2)~$D_{8\varphi}\times A_5,\,{\rm ker}\varphi=Z_2\times Z_2$; (3)~$G/N=S_5$, $N=Z(G)=Z_2$; (4)~$G/N=S_5$, $N=Z_2\times Z_2,\,N\cap Z(G)=Z_2$. 相似文献
997.
We prove that any mapping class on a compact oriented surface with non-empty boundary can be made pseudo-Anosov and right-veering
after a sequence of positive stabilizations.
相似文献
998.
S. Tazhetdinov 《Siberian Mathematical Journal》2008,49(1):175-179
We describe the subnormal subgroups of 2-dimensional linear groups over local and full rings in which 2 is invertible, as well as the subnormal subgroups of symplectic groups over local rings in which 2 is invertible. 相似文献
999.
Let f : U → X be a map from a connected nilpotent space U to a connected rational space X. The evaluation subgroup G
*(U, X; f), which is a generalization of the Gottlieb group of X, is investigated. The key device for the study is an explicit Sullivan model for the connected component containing f of the function space of maps from U to X, which is derived from the general theory of such a model due to Brown and Szczarba (Trans Am Math Soc 349, 4931–4951, 1997).
In particular, we show that non Gottlieb elements are detected by analyzing a Sullivan model for the map f and by looking at non-triviality of higher order Whitehead products in the homotopy group of X. The Gottlieb triviality of a fibration in the sense of Lupton and Smith (The evaluation subgroup of a fibre inclusion, 2006)
is also discussed from the function space model point of view. Moreover, we proceed to consideration of the evaluation subgroup
of the fundamental group of a nilpotent space. In consequence, the first Gottlieb group of the total space of each S
1-bundle over the n-dimensional torus is determined explicitly in the non-rational case.
相似文献
1000.
We generalize some identities and q-identities previously known for the symmetric group to Coxeter groups of type B and D. The extended results include theorems of Foata and Schützenberger, Gessel, and Roselle on various distributions of statistics, like inversion number, major index, and descent number. In order to show our results we provide explicit characterizations of the systems of minimal coset representatives of Coxeter groups of type B and D. 相似文献