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261.
Sabine Klapp 《Angewandte Chemie (International ed. in English)》2001,40(12):2359-2359
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Kinetic and polymer analytical results obtained with the systems Me2Si(Ind)2ZrMe2/[B(C6F4Si(i-Pr)3)4]− [(C6H5)3C]+ (2) and Me2Si(Ind)2ZrMe2/[B(C6F5)4]− [(C6H5)3C]+ (3) in olefin polymerizations are compared (Me: methyl; Ind: indenyl). Both systems show that the polymerization rate increases with increasing metallocene concentration in a surplus due to the formation of binuclear species. The expected influence of increasing cation-anion distance on the stereo-errors of the poly(propylene)s when changing from system 3 into system 2 could not be detected. 相似文献
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Emmanuel Cadot Bernadette Salignac Sabine Halut Francis Scheresse 《Angewandte Chemie (International ed. in English)》1998,37(5):611-613
The pH-dependent self-condensation of the [Mo 2 S 2 O 2 ] 2+ complex fragment gives the wheellike Mo12 cluster depicted on the right (ball-and-stick model; large balls: S, medium balls: O, small balls: Mo). Applying this synthetic strategy to other starting materials could provide access to other polyoxothiometalates with well-defined cavities. 相似文献
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Andreas Pfau Peter Hssel Sabine Vogt Ralf Sander Wolfgang Schrepp 《Macromolecular Symposia》1998,126(1):241-252
We present a combination of electrochemical methods, i.e. polyelectrolyte titration and streaming potential measurement, and AFM to characterise the adsorption and desorption behaviour and the morphology of a set of polyquaternium polymers on human hair. Specific charge density and molar mass are correlated to the amount of adsorbed polymer and the ease of desorption. Results are in line with a simple model of coulombic interaction between hair and polymer and are interpreted on this basis. 相似文献
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Sabine Schlecht Dirk V. Deubel Gernot Frenking Gertraud Geiseler Klaus Harms Jrg Magull Kurt Dehnicke 《无机化学与普通化学杂志》1999,625(6):887-891
Phosphoraneiminato Complexes of Rhenium(VII). Syntheses and Crystal Structures of [ReO3(NPR3)] (R = Ph, Et) and of [ReO(OSiMe3)3(Me3SiNPEt3)] The phosphoraneiminato complexes [ReO3(NPR3)] with R = Ph ( 1 ) and R = Et ( 2 ) are made from dirhenium heptaoxide and the silylated phosphoraneimines Me3SiNPR3. The complexes 1 and 2 as well as the red silanolate [ReO(OSiMe3)3(Me3SiNPEt3)] ( 3 ), which is formed as a by‐product in the synthesis of 2 , are characterized crystallographically. 1 and 2 are monomeric molecules, in which the phosphoraneiminato ligands NPR3– realize short ReN bonds of 179.3 pm ( 1 ) and 178.6 pm ( 2 ), respectively, with large ReNP bond angles of 162.0° ( 1 ) and 160.6° ( 2 ), respectively. In the rhenium(V) complex 3 the oxoligand occupies the apical position of the tetragonal pyramidal coordination of the rhenium atom, while the oxygen atoms of the Me3SiO– groups take the basic positions along with the nitrogen atom of the phosphaneimine molecule. 相似文献
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Gerhart Braunegg Anna de Raadt Sabine Feichtenhofer Herfried Griengl Irene Kopper Antje Lehmann Hans-Jorg Weber 《Angewandte Chemie (International ed. in English)》1999,38(18):2763-2766
A general principle for biohydroxylation , in which time-consuming screening and enrichment techniques are avoided, is demonstrated by the introduction of a docking/protecting group into the substrate. This facilitates acceptance by the microorganism and allows the use of a narrow range of microorganisms, for example Beauveria bassiana ATTC 7159 (B. b.), for the hydroxylation of compounds with diverse structures. After the biohydroxylation, the docking/protecting group is removed (see scheme). 相似文献