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41.
Arno Behr Thomas Beckmann Pierre Schwach 《Journal of organometallic chemistry》2008,693(18):3097-3102
Two different routes to acetoxyoctadiene are presented. The first one uses the well-known telomerisation of butadiene with acetic acid operating in a multiphase semi-batch mode. The second reaction involves the cleavage of acetic anhydride, hydrogen transfer via ketene formation and thus a telomerisation as well. 相似文献
42.
Uwe Klingebiel Stefan Schmatz Eike Gellermann Christian Drost Mathias Noltemeyer 《Monatshefte für Chemie / Chemical Monthly》2001,40(5):1105-1124
This review describes the synthesis and isomerization reactions of cyclic silylhydrazines. Topics of discussion are the ring
expansion of the three-membered Si(SiN2) to the four-membered (SiN)2 ring by lithiation of the (SiN2) ring and by thermal silyl group insertion into the N*N bond, the ring expansion of a three-membered (SiN2) to a five-membered (CSi2N2) ring by SiCH2 insertion into the Si*N bond, the formation of isomeric four- and six-membered (SiN2)2 rings, the synthesis of five- and six-membered silylhydrazine rings, and the expansion of a five-membered (N2Si2N)N ring to the isomeric six-membered (SiNN)2 ring. The mechanisms of the isomerizations are explained by quantum chemical calculations, and the results are verified by
crystal structure determinations. 相似文献
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We correlate an X-ray determination of the molecular and crystal structures of 2-tert-butylanthracene and 2-tert-butylanthraquinone reported here with the previously reported dynamical nuclear magnetic resonance determination of the motions of the tert-butyl groups and their resident methyl groups in the solid state [P.A. Beckmann, K.S. Burbank, M.M.W. Lau, J.N. Ree, T.L. Weber, Chem. Phys. 290 (2003) 241]. 相似文献
46.
Eike Lau 《Inventiones Mathematicae》2008,171(3):617-628
Over p-adic Nagata rings, formal p-divisible groups are classified by nilpotent displays according to T. Zink. We extend this result to arbitrary p-adic rings. The proof uses the Grothendieck–Illusie deformation theory of truncated p-divisible groups. 相似文献
47.
E. Beckmann 《Fresenius' Journal of Analytical Chemistry》1902,41(9):559-560
Ohne Zusammenfassung 相似文献
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49.
Based on continuous methodical advances and developments, solid-state NMR spectroscopy has become a powerful tool for the
investigation of various materials, including polymers, glasses, zeolites, fullerenes, and many others. During the past decade,
solid-state NMR spectroscopy also found increasing interest for the study of biomolecules. For example, membrane proteins
reconstituted into lipid environments such as bilayers or vesicles, protein aggregates such as amyloid fibrils, as well as
carbohydrates can now be studied by solid-state NMR spectroscopy. This review briefly introduces the principles of solid-state
NMR spectroscopy and highlights novel methodical trends. Selected applications demonstrate the possibilities of solid-state
NMR spectroscopy as a valuable bioanalytical tool. 相似文献
50.
It is well-known that the Artin-Mazur dynamical zeta function of a hyperbolic or quasi-hyperbolic toral automorphism is a rational function, which can be calculated in terms of the eigenvalues of the corresponding integer matrix. We give an elementary proof of this fact that extends to the case of general toral endomorphisms without change. The result is a closed formula that can be calculated by integer arithmetic only. We also address the functional equation and the relation between the Artin-Mazur and Lefschetz zeta functions. 相似文献