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1.
Edelsbacher Philipp Redhammer Gnther Monkowius Uwe 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):543-547
Monatshefte für Chemie - Chemical Monthly - Four members of a new series of paddle-wheel copper(II) complexes bearing cyclobutanecarboxylate as bridging ligand with pyridine derived ligands in... 相似文献
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Mechanistic Aspects of a Highly Active Dinuclear Zinc Catalyst for the Co‐polymerization of Epoxides and CO2
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Stefan Kissling Peter T. Altenbuchner Dr. Maximilian W. Lehenmeier Dr. Eberhardt Herdtweck Dr. Peter Deglmann Dr. Uwe B. Seemann Prof. Dr. Bernhard Rieger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8148-8157
The dinuclear zinc complex reported by us is to date the most active zinc catalyst for the co‐polymerization of cyclohexene oxide (CHO) and carbon dioxide. However, co‐polymerization experiments with propylene oxide (PO) and CO2 revealed surprisingly low conversions. Within this work, we focused on clarification of this behavior through experimental results and quantum chemical studies. The combination of both results indicated the formation of an energetically highly stable intermediate in the presence of propylene oxide and carbon dioxide. A similar species in the case of cyclohexene oxide/CO2 co‐polymerization was not stable enough to deactivate the catalyst due to steric repulsion. 相似文献
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Back Cover: Reactions of Group 4 Metallocenes with Monosubstituted Acetonitriles: Keteniminate Formation versus CC Coupling (Chem. Eur. J. 8/2015)
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Erwin Bolthausen Jean-Dominique Deuschel Uwe Schmock 《Probability Theory and Related Fields》1993,95(3):283-310
Summary We discuss the limiting path measures of Markov processes with either a mean field or a polaron type interaction of the paths. In the polaron type situation the strength is decaying at large distances on the time axis, and so the interaction is of short range in time. In contrast, in the mean field model, the interaction is weak, but of long range in time. Donsker and Varadhan proved that for the partition functions, there is a transition from the polaron type to the mean field interaction when passing to a limit by letting the strength tend to zero while increasing the range. The discussion of the path measures is more subtle. We treat the mean field case as an example of a differentiable interaction and discuss the transition from the polaron type to the mean field interaction for two instructive examples.Research supported by the Swiss National Foundation (21-29833.90)This article was processed by the authors using the Springer-Verlag TEX ProbTh macro package 1991. 相似文献
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Sven Walter 《Acta Analytica》2005,20(3):32-47
Frank Jackson and Philip Pettit have defended a non-reductive account of causal relevance known as the ‘program explanation
account’. Allegedly, irreducible mental properties can be causally relevant in virtue of figuring in non-redundant program explanations which convey information not conveyed by explanations in terms of the physical properties that actually do the ‘causal work’.
I argue that none of the possible ways to spell out the intuitively plausible idea of a program explanation serves its purpose,
viz., defends non-reductive physicalism against Jaegwon Kim’s Causal Exclusion Argument according to which non-reductive physicalism is committed to epiphenomenalism because irreducible mental properties are ‘screened
off’ from causal relevance by their physical realizers. Jackson and Pettit’s most promising explication of a program explanation
appeals to the idea of invariance of effect under variation of realization, but I show that invariance of effect under variation of realization is neither necessary nor sufficient for causal relevance. 相似文献
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Received December 31, 2001 / Published online May 21, 2002 相似文献
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Velislava A Ignatova Sven Van Den Berghe Steven Van Dyck Vladimir N Popok 《Microscopy and microanalysis》2006,12(5):432-437
The oxide scales of AISI 304 formed in boric acid solutions at 300 degrees C and pH = 4.5 have been studied using X-ray photoelectron spectroscopy (XPS) depth profiling. The present focus is depth profile quantification both in depth and chemical composition on a molecular level. The roughness of the samples is studied by atomic force microscopy before and after sputtering, and the erosion rate is determined by measuring the crater depth with a surface profilometer and vertical scanning interferometry. The resulting roughness (20-30 nm), being an order of magnitude lower than the crater depth (0.2-0.5 microm), allows layer-by-layer profiling, although the ion-induced effects result in an uncertainty of the depth calibration of a factor of 2. The XPS spectrum deconvolution and data evaluation applying target factor analysis allows chemical speciation on a molecular level. The elemental distribution as a function of the sputtering time is obtained, and the formation of two layers is observed-one hydroxide (mainly iron-nickel based) on top and a second one deeper, mainly consisting of iron-chromium oxides. 相似文献