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41.
In a previous paper [31] we established the complex analytic manifold theory of the BMO-Teichmüller space. In this paper we identify the function space which is the tangent space to the BMO-Teichmüller space. 相似文献
42.
We discuss the existence of the angle between two curves in Teichmüller spaces and show that, in any infinite dimensional Teichmüller space, there exist infinitely many geodesic triangles each of which has the same three vertices and satisfies the property that its three sides have the same and arbitrarily given length while its three angles are equal to any given three possibly different numbers from 0 to $\pi $ . This implies that the sum of three angles of a geodesic triangle may be equal to any given number from 0 to $3\pi $ in an infinite dimensional Teichmüller space. 相似文献
43.
Asymmetric 1,4‐conjugation addition of dialkylzinc (diethylzinc and dimethylzinc) to cyclic enones, chalcone and nitroalkenes was achieved by a 25 mol% (R)‐6,6′‐Br2‐BINOL( 1f ), 25 mol% CuSPh and 100 mol% dicyclohexylmethylamin(Cy2NMe) catalyst system. The Cu(I) catalyst system enables the cyclic enone, chalcone and nitroalkene generality with high enantioselectivity (up to 84% ee) and isolated yield (up to 94%) under mild reaction conditions. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
44.
45.
We will be mainly concerned with some important fiber spaces over Teichmüller spaces, including the Bers fiber space and Teichmüller
curve, establishing an isomorphism theorem between “punctured” Teichmüller curves and determining the biholomorphic isomorphisms
of these fiber spaces. 相似文献
46.
47.
采用高频感应炉燃烧–红外吸收法测定银杏叶、银杏果肉、银杏壳和银杏仁中的硫含量。样品以艾士卡试剂为熔融剂,在800℃马弗炉内熔融1 h,冷却后测定硫含量。硫的质量分数在0.40%~4.00%范围内与吸收峰面积呈良好的线性关系,线性相关系数为0.990 4,检出限为0.000 9%。测定结果的相对标准偏差为4.04%(n=11),平均加标回收率为101.03%。将红外吸收法与电感耦合等离子体原子发射光谱法及硫酸钡重量法进行比对试验,3种方法测定结果相一致。利用该方法测定了不同区域银杏叶中硫的含量,结果表明,风景区和居民区银杏叶干燥基全硫的含量较低,重工业区硫含量较高。对同一地区的银杏果肉、银杏壳、银杏仁中干燥基全硫的含量进行比较,结果表明银杏果肉硫含量最高,银杏壳次之,银杏仁最低。该方法灵敏度高,重现性好,可用于银杏及银杏叶中硫含量的准确测定。 相似文献
48.
The rod–coil diblock copolymers in which the donor–acceptor alternating structures served as the rod segment were synthesized.
The supramolecular self-assembly property of the copolymers was investigated in the methanol atmosphere. By changing the assembly
condition, well-defined vesicles and porous films were produced, respectively. Pores with different size dispersions were
obtained by tuning the methanol atmosphere. Moreover, porous films were also decorated on diverse substrates with nonplanar
structures. The investigation on self-assembly properties of this rod–coil copolymer is the complementarity to the self-assembly
of rod–coil copolymers. This is a very useful self-assembly method that can be used to prepare the self-assembly nanostructures
with donor–acceptor alternating copolymers. 相似文献
49.
A spectral method of self-consistent field theory has been applied to AB cyclic block copolymers. Phase behaviors of cyclic diblock copolymers, such as order-disorder transition, order-order transition, and domain spacing size, have been studied, showing good consistency with previous experimental and theoretical results. Compared to linear diblocks, cyclic diblocks are harder to phase separate due to the topological constraint of the ring structure. A direct disorder-to-cylinder transition window is observed in the phase diagram, which is significantly different from the mean field phase diagram of linear diblock copolymers. The domain spacing size ratio between cyclic and linear diblock copolymers is typically close to 0.707, indicating in segregation that the cyclic polymer can be considered to be made up of linear diblocks with half of the original chain length. 相似文献
50.
Sun Z Wang Y Wei Y Liu R Zhu H Cui Y Zhao Y Gao X 《Chemical communications (Cambridge, England)》2011,47(43):11960-11962
Silver cluster-aptamer hybrids were mineralized via an artificially designed aptamer. The hybrids gave red emission when excited by light, and they successfully targeted the nucleus of live cells. This method is an effective approach to make cell target probes. 相似文献