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Boris Vertman 《Annals of Global Analysis and Geometry》2012,41(1):61-90
The formula for analytic torsion of a cone in even dimensions is composed of three terms. The first two terms are well understood
and given by an algebraic combination of the Betti numbers and the analytic torsion of the cone base. The third “singular”
contribution is an intricate spectral invariant of the cone base. We identify the third term as the metric anomaly of the
analytic torsion coming from the non-product structure of the cone at its regular boundary. Hereby we filter out the actual
contribution of the concial singularity and identify the analytic torsion of an even-dimensional cone purely in terms of the
Betti numbers and the analytic torsion of the cone base. 相似文献
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Boris A. Trofimov Ludmila A. Oparina Lidiya N. Parshina Marina Ya. Khil’ko Anatolii P. Tantsyrev Galina P. Aleksandrova 《Cellulose (London, England)》2013,20(3):1201-1214
Diverse celluloses including non-mercerized and mercerized ones have been successfully vinylated with acetylene in the superbase catalytic systems MOH/DMSO and MOH/THF (M = Na, K) at 85–140 °C. Depending on the reaction conditions, degree of substitution of the hydroxyl groups by highly reactive polymerazable vinyloxy groups ranges 0.11–1.22, the yields of vinylated celluloses (insoluble in water, but soluble in DMSO) being 41–89 %. Vinylated celluloses are easily decomposed under the action of white rot fungi: Phanerochaete chrysosporium, Trametes versicolor and Trametes hirsutus, and can constitute a basis for the preparation of biodegradable polymer materials (due to polymerization or polyaddition at the vinyloxy group). 相似文献
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Li Zhang Dr. Julie Jung Dr. Peng Zhang Mei Guo Dr. Lang Zhao Prof. Dr. Jinkui Tang Prof. Dr. Boris Le Guennic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1392-1398
Elaborate chemical design is of utmost importance in order to slow down the relaxation dynamics in single‐molecule magnets (SMMs) and hence improve their potential applications. Much interest was devoted to the study of distinct relaxation processes related to the different crystal fields of crystallographically independent lanthanide ions. However, the assignment of the relaxation processes to specific metal sites remains a challenging task. To address this challenge, a new asymmetric Dy2 SMM displaying a well‐separated two‐step relaxation process with the anisotropic centers in fine‐tuned local environments was elaborately designed. For the first time a one‐to‐one relationship between the metal sites and the relaxation processes was evidenced. This work sheds light on complex multiple relaxation and may direct the rational design of lanthanide SMMs with enhanced magnetic properties. 相似文献