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81.
X-ray crystal structures of the inclusion complexes of calix[4]arene monomethoxycarboxylic acid 1 (C30H2606) with acetontrile and acetone are reported. The crystal of C30H26O6·CH3CN is of monoclinic, space group P2 1/c with a = 11.691(5), b = 13.753(5), c = 17.072(7)A, β = 100.104(7)°, C32H29NO6, Mr = 523.56, V = 2702.4(18)A^3, Z = 4, De= 1.287 g/cm^3, μ(MoKα) = 0.089 mm^-1, T = 293(2) K, 5570 independent reflections with 3220 observed ones (1 〉 2σ(I)), R = 0.0521 and wR = 0.1132 with GOF = 1.042 (R = 0.1055 and wR = 0.1350 for all data). The data for C30H26O6·CH3COCH3: monoclinic, space group P2 1/c, α = 12.366(4), b = 12.119(4), c = 18.796(6) A, β = 90.871(6)°, C33H32O7, Mr = 540.59, V = 2816.6(16)A^3, Z = 4, Dc = 1.275 g/cm^3, μ(MoKα) = 0.089 mm^-1, T = 293(2) K, 5783 independent reflections including 2580 observed ones (I 〉 2σ(I)), R = 0.0555 and wR = 0.1424 with GOF= 0.975 (R = 0.1601 and wR = 0.1884 for all data). Their architectures exhibit one-dimensional inclusion polymers which are mediated head-to-tail by the guests. 相似文献
82.
The de Sitter special relativity on the Beltrami-de Sitter-spacetime and Snyder's model in the momentum space can be combined together with an IR-UV duality to get the complete Yang model at both classical and quantum levels, which are related by the proposed Killing quantization. It is actually a special relativity based on the principle of relativity of three universal constants (c, ρp, R). 相似文献
83.
随着家居品牌“达芬奇”被媒体曝光其产品并非全部原装进口,“假洋品牌”盛行国内的现象再次引发广泛关注。何为假洋品牌?假洋品牌是指国人控制的公司在国外注册商标,于国内生产销售,误导消费者牟取暴利的品牌。按照鲁迅所说,就是“假洋鬼子”。 相似文献
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85.
Huanyin CHEN 《数学年刊B辑(英文版)》2009,30(3):221-230
The necessary and sufficient conditions under which a ring satisfies regular power-substitution are investigated. It is shown that a ring R satisfies regular powersubstitution if and only if a-b in R implies that there exist n ∈ N and a U E GLn (R) such that aU = Ub if and only if for any regular x ∈ R there exist m,n ∈ N and U ∈ GLn(R) such that x^mIn = xmUx^m, where a-b means that there exists x,y, z∈ R such that a =ybx, b = xaz and x= xyx = xzx. It is proved that every directly finite simple ring satisfies regular power-substitution. Some applications for stably free R-modules are also obtained. 相似文献
86.
Let G be a locally compact Abelian group with Haar measure. The authors discuss some basic properties of Lw1^r (G)∩ L(p, q, w2dμ)(G) spaces. Then the necessary conditions for compact embeddings of the spaces Lw1^r (R^d)∩ L(p, q, w2dμ)(R^d) are showed. 相似文献
87.
Theoretical Study of Isotopic Effect of Oxygen Atom on the Stereodynamics for the O(^3P) + D2 → OD + D Reaction
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Quasi-classical trajectory theory is used to study the isotope effect of oxygen atoms on the vector correlations in the O(^3P) + D reaction at a collision energy of 25kcal/mol using accurate potential energy surface of the 3A' triplet state. The distributions of p(θr) and the distribution of dihedral angel p(φr) as well as p(θr,φr) are calculated. Moreover, four polarization-dependent generalized differential cross sections (PDDCSs) of product are presented in the center-of-mass frame. The results indicate that the polarization of the product presents different characters for the isotope effect of oxygen atoms. Isotopic substitute can cause obviously different effects on the four PDDCSs. 相似文献
88.
In this article, using coordinate transformation and Gronwall inequality, we study the vortex motion law of the anisotropic Ginzburg-Landau equation in a smooth bounded domain Ω R2, that is, ■tuε = 2Σ/j,k=1 (ajkj■xjkuε)xj + b(x)(1-ε|ε|2)uε/2u, x ∈Ω, and conclude that each vortex bj(t) (j=1, 2,···, N) satisfies dbdjt(t)= -(a1k(bj(t)b)■(xk))a(a (bj(t)), a2k(bj (t))/xk a(bj (t)) a(bj (t)) , where a(x) =(a11a22-a122(1/2)). We prove that all the vortices are pinned together to the critical points of a(x). Furthermore, we prove that these critical points can not be the maximum points. 相似文献