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1.
Stefan Spange Frank Simon Heidrun Schutz Andrea Schramm Heinz Winkelmann 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):997-1006
Abstract The preparation of cationically active oligo-p-methoxystyrene-silica composites by cationic interfacial polymerization is described. In addition to the effective preparation of the interfacial initiator, p-methoxybenzylium-hydrogen sulfate-silica, and p-methoxybenzylium-trifluoroacetate-silica, a procedure to yield new kinds of composites is reported. The outstanding properties of the “living” oligo-p-methoxy-styryl-hydrogen sulfate-silica is demonstrated by means of zeta potential measurements, solid-state 13C-NMR spectroscopy, UV/Vis spectroscopy, and electron scanning microscopy. 相似文献
2.
The Morse–Witten theory provides a formulation for the inter-bubble forces and corresponding deformations in a liquid foam, accurate in the limit of high liquid fraction. Here we show how the theory may be applied in practice, including allowing for polydispersity in the bubble sizes. The resulting equilibrated 2D structures are consistent with direct calculations, within the limitations of the theory. The path to developing a 3D model is outlined for future work. 相似文献
3.
Peez Nadine Becker Jochen Ehlers Sonja M. Fritz Melanie Fischer Christian B. Koop Jochen H. E. Winkelmann Carola Imhof Wolfgang 《Analytical and bioanalytical chemistry》2019,411(28):7603-7603
Analytical and Bioanalytical Chemistry - The original version of this article contained a mistake. 相似文献
4.
Jörg Winkelmann 《Transformation Groups》2008,13(1):195-209
We study non-Kähler manifolds with trivial logarithmic tangent bundle. We show that each such manifold arises as a fibre bundle with a compact complex parallelizable manifold as basis and a compactficiation of a semi-torus as fibre. 相似文献
5.
6.
Preparation and properties are described of the complexes resulting by reaction of methylene-bis(diphenylphosphine) (MDP) and lithium-bis(diphenylphosphino)-methanide with π-allyl-pallladium chloride. (π-C3H5PdCl)2 gives with MDP 1:1 and 1:2 complexes, whereas a 1:3 complex is not obtained. LiCH(PPh2)2 reacts with PdCl2 and (π-C3H5PdCl)2 to form [(PPh2)2 CHPdCl]2 and [π-C3H5PdCH(PPh2)2]2, respectively. These compounds are dimeric by associating via phosphine bridges. The latter are cleaved on heating with one mole of MDP. The compounds were characterized by IR and UV/VIS absorption spectra, conductivity and tested for catalytic properties. 相似文献
7.
H.H. Bingham D.M. Chew W.B. Fretter W.R. Graves L. Stutte G.P. Yost G.S. Abrams B.Y. Daugéras C.E. Friedberg G. Goldhaber A.D. Johnson J.A. Kadyk G.H. Trilling F.C. Winkelmann D. Bogert R. Hanft F.R. Huson D. Ljung W.M. Smart 《Physics letters. [Part B]》1974,51(4):397-401
In a 48 000-picture exposure of the Fermilab 30-inch hydrogen bubble chamber to a 205 GeV/cπ?beam, we have measured 169 events of the reaction, π?p→π?π+π?p, with a cross section of 635 ± 61 μb. This reaction proceeds almost entirely via low mass π? → 3π and p → pππ dissociation. Factorization is satisfied for p → pππ dissociation in πp and pp interactions. 相似文献
8.
An electrical stagnation point probe used to measure ion densities of flowing high pressure plasmas (p = 105 Pa) was developed. The experimental results of a probe operating in the sheath — convection regime confirm the validity of the used theory according to the shape of the characteristic and the measured ion density compared with spectroscopical values. The deviation between both techniques is less than a half order of magnitude. 相似文献
9.
Let X be a compact complex homogeneous manifold and let Aut(X) be the complex Lie group of holomorphic automorphisms of X. It is well-known that the dimension of Aut(X) is bounded by an integer that depends only on n=dim
X. Moreover, if X is K?hler then dimAut (X)≤n(n+2) with equality only when X is complex projective space. In this article examples of non-K?hler compact complex homogeneous manifolds X are given that demonstrate dimAut(X) can depend exponentially on n.
Let X be a connected compact complex manifold of dimension n. The group of holomorphic automorphisms of X, Aut(X), is a complex Lie group [3]. For a fixed n>1, the dimension of Aut(X) can be arbitrarily large compared to n. Simple examples are provided by the Hirzebruch surfaces F
m
, m∈N, for which dimAut(F
m
)=m+5, see, e.g. [2, Example 2.4.2].
If X is homogeneous, that is, any point of X can be mapped to any other point of X under a holomorphic automorphism, then the dimension of the automorphism group of X is bounded by an integer that depends only on n, see [1, 2, 6]. The estimate given in [2, Theorem 3.8.2] is roughly dimAut(X)≤(n+2)
n
. For many classes of manifolds, however, the dimension of the automorphism group never exceeds n(n+2). For example, it follows directly from the classification given by Borel and Remmert [4], that if X is a compact homogeneous K?hler manifold, then dimAut(X)≤n(n+2) with equality only when X is complex projective space P
n
. It is an old question raised by Remmert, see [2, p. 99], [6], whether this same bound applies to all compact complex homogeneous
manifolds.
In this note we show that this is not the case by constructing non-K?hler compact complex homogeneous manifolds whose automorphism
group has a dimension that depends exponentially on n. The simplest case among these examples has n=3m+1 and dimAut(X)=3m+3
m
, so the above conjectured bound is exceeded when n≥19. These manifolds have the structure of non-trivial fiber bundles over products of flag manifolds with parallelizable fibers
given as the quotient of a solvable group by a discrete subgroup. They are constructed using the original ideas of Otte [6,
7] and are surprisingly similar to examples found there. Generally, a product of manifolds does not result in an automorphism
group with a large dimension relative to n. Nevertheless, products are used in an essential way in the construction given here, and it is perhaps this feature that
caused such examples to be previously overlooked.
Oblatum 13-X-97 & 24-X-1997 相似文献
10.